diff options
Diffstat (limited to 'src')
500 files changed, 37047 insertions, 24118 deletions
diff --git a/src/builtin/builtin.go b/src/builtin/builtin.go index 4578c855a9..c78fe09ea6 100644 --- a/src/builtin/builtin.go +++ b/src/builtin/builtin.go @@ -152,6 +152,9 @@ func delete(m map[Type]Type1, key Type) // String: the number of bytes in v. // Channel: the number of elements queued (unread) in the channel buffer; // if v is nil, len(v) is zero. +// For some arguments, such as a string literal or a simple array expression, the +// result can be a constant. See the Go language specification's "Length and +// capacity" section for details. func len(v Type) int // The cap built-in function returns the capacity of v, according to its type: @@ -161,6 +164,9 @@ func len(v Type) int // if v is nil, cap(v) is zero. // Channel: the channel buffer capacity, in units of elements; // if v is nil, cap(v) is zero. +// For some arguments, such as a simple array expression, the result can be a +// constant. See the Go language specification's "Length and capacity" section for +// details. func cap(v Type) int // The make built-in function allocates and initializes an object of type diff --git a/src/bytes/buffer.go b/src/bytes/buffer.go index 14c5bc38d6..087cc0e427 100644 --- a/src/bytes/buffer.go +++ b/src/bytes/buffer.go @@ -12,13 +12,15 @@ import ( "unicode/utf8" ) +// smallBufferSize is an initial allocation minimal capacity. +const smallBufferSize = 64 + // A Buffer is a variable-sized buffer of bytes with Read and Write methods. // The zero value for Buffer is an empty buffer ready to use. type Buffer struct { - buf []byte // contents are the bytes buf[off : len(buf)] - off int // read at &buf[off], write at &buf[len(buf)] - bootstrap [64]byte // memory to hold first slice; helps small buffers avoid allocation. - lastRead readOp // last read operation, so that Unread* can work correctly. + buf []byte // contents are the bytes buf[off : len(buf)] + off int // read at &buf[off], write at &buf[len(buf)] + lastRead readOp // last read operation, so that Unread* can work correctly. // FIXME: it would be advisable to align Buffer to cachelines to avoid false // sharing. @@ -125,9 +127,8 @@ func (b *Buffer) grow(n int) int { if i, ok := b.tryGrowByReslice(n); ok { return i } - // Check if we can make use of bootstrap array. - if b.buf == nil && n <= len(b.bootstrap) { - b.buf = b.bootstrap[:n] + if b.buf == nil && n <= smallBufferSize { + b.buf = make([]byte, n, smallBufferSize) return 0 } c := cap(b.buf) diff --git a/src/bytes/bytes.go b/src/bytes/bytes.go index 77a7ce98e0..6492db088a 100644 --- a/src/bytes/bytes.go +++ b/src/bytes/bytes.go @@ -774,6 +774,15 @@ func Replace(s, old, new []byte, n int) []byte { return t[0:w] } +// ReplaceAll returns a copy of the slice s with all +// non-overlapping instances of old replaced by new. +// If old is empty, it matches at the beginning of the slice +// and after each UTF-8 sequence, yielding up to k+1 replacements +// for a k-rune slice. +func ReplaceAll(s, old, new []byte) []byte { + return Replace(s, old, new, -1) +} + // EqualFold reports whether s and t, interpreted as UTF-8 strings, // are equal under Unicode case-folding. func EqualFold(s, t []byte) bool { @@ -849,21 +858,22 @@ func Index(s, sep []byte) int { if len(s) <= bytealg.MaxBruteForce { return bytealg.Index(s, sep) } - c := sep[0] + c0 := sep[0] + c1 := sep[1] i := 0 - t := s[:len(s)-n+1] + t := len(s) - n + 1 fails := 0 - for i < len(t) { - if t[i] != c { + for i < t { + if s[i] != c0 { // IndexByte is faster than bytealg.Index, so use it as long as // we're not getting lots of false positives. - o := IndexByte(t[i:], c) + o := IndexByte(s[i:t], c0) if o < 0 { return -1 } i += o } - if Equal(s[i:i+n], sep) { + if s[i+1] == c1 && Equal(s[i:i+n], sep) { return i } fails++ @@ -879,24 +889,25 @@ func Index(s, sep []byte) int { } return -1 } - c := sep[0] + c0 := sep[0] + c1 := sep[1] i := 0 fails := 0 - t := s[:len(s)-n+1] - for i < len(t) { - if t[i] != c { - o := IndexByte(t[i:], c) + t := len(s) - n + 1 + for i < t { + if s[i] != c0 { + o := IndexByte(s[i:t], c0) if o < 0 { break } i += o } - if Equal(s[i:i+n], sep) { + if s[i+1] == c1 && Equal(s[i:i+n], sep) { return i } i++ fails++ - if fails >= 4+i>>4 && i < len(t) { + if fails >= 4+i>>4 && i < t { // Give up on IndexByte, it isn't skipping ahead // far enough to be better than Rabin-Karp. // Experiments (using IndexPeriodic) suggest diff --git a/src/bytes/bytes_test.go b/src/bytes/bytes_test.go index 55a22bae22..f4c0ffd2a9 100644 --- a/src/bytes/bytes_test.go +++ b/src/bytes/bytes_test.go @@ -1362,6 +1362,12 @@ func TestReplace(t *testing.T) { if cap(in) == cap(out) && &in[:1][0] == &out[:1][0] { t.Errorf("Replace(%q, %q, %q, %d) didn't copy", tt.in, tt.old, tt.new, tt.n) } + if tt.n == -1 { + out := ReplaceAll(in, []byte(tt.old), []byte(tt.new)) + if s := string(out); s != tt.out { + t.Errorf("ReplaceAll(%q, %q, %q) = %q, want %q", tt.in, tt.old, tt.new, s, tt.out) + } + } } } diff --git a/src/cmd/asm/internal/asm/testdata/386.s b/src/cmd/asm/internal/asm/testdata/386.s index 90a66167a1..d524a4c8c1 100644 --- a/src/cmd/asm/internal/asm/testdata/386.s +++ b/src/cmd/asm/internal/asm/testdata/386.s @@ -70,7 +70,7 @@ label: // LTYPEM spec6 { outcode(int($1), &$2); } MOVL AX, BX MOVL $4, BX - + // LTYPEI spec7 { outcode(int($1), &$2); } IMULL AX IMULL $4, CX diff --git a/src/cmd/asm/internal/asm/testdata/arm64.s b/src/cmd/asm/internal/asm/testdata/arm64.s index 361b7a45c0..9e2e2b1dc5 100644 --- a/src/cmd/asm/internal/asm/testdata/arm64.s +++ b/src/cmd/asm/internal/asm/testdata/arm64.s @@ -654,6 +654,7 @@ again: CALL foo(SB) // LDP/STP + LDP (R0), (R0, R1) // 000440a9 LDP (R0), (R1, R2) // 010840a9 LDP 8(R0), (R1, R2) // 018840a9 LDP -8(R0), (R1, R2) // 01887fa9 diff --git a/src/cmd/asm/internal/asm/testdata/arm64enc.s b/src/cmd/asm/internal/asm/testdata/arm64enc.s index ee4673c1ae..432ab74493 100644 --- a/src/cmd/asm/internal/asm/testdata/arm64enc.s +++ b/src/cmd/asm/internal/asm/testdata/arm64enc.s @@ -188,8 +188,8 @@ TEXT asmtest(SB),DUPOK|NOSPLIT,$-8 MOVBU (R18)(R14<<0), R23 // 577a6e38 MOVBU (R2)(R8.SXTX), R19 // 53e86838 MOVBU (R27)(R23), R14 // MOVBU (R27)(R23*1), R14 // 6e6b7738 - MOVHU.P 107(R13), R13 // adb54678 - MOVHU.W 192(R2), R2 // 420c4c78 + MOVHU.P 107(R14), R13 // cdb54678 + MOVHU.W 192(R3), R2 // 620c4c78 MOVHU 6844(R4), R18 // 92787579 MOVHU (R5)(R25.SXTW), R15 // afc87978 //TODO MOVBW.P 77(R18), R11 // 4bd6c438 diff --git a/src/cmd/asm/internal/asm/testdata/arm64error.s b/src/cmd/asm/internal/asm/testdata/arm64error.s index b2ec0cc425..357db80222 100644 --- a/src/cmd/asm/internal/asm/testdata/arm64error.s +++ b/src/cmd/asm/internal/asm/testdata/arm64error.s @@ -8,7 +8,19 @@ TEXT errors(SB),$0 ADDSW R7->32, R14, R13 // ERROR "shift amount out of range 0 to 31" ADD R1.UXTB<<5, R2, R3 // ERROR "shift amount out of range 0 to 4" ADDS R1.UXTX<<7, R2, R3 // ERROR "shift amount out of range 0 to 4" + AND $0x22220000, R2, RSP // ERROR "illegal combination" + ANDS $0x22220000, R2, RSP // ERROR "illegal combination" + ADD R1, R2, R3, R4 // ERROR "illegal combination" BICW R7@>33, R5, R16 // ERROR "shift amount out of range 0 to 31" + CINC CS, R2, R3, R4 // ERROR "illegal combination" + CSEL LT, R1, R2 // ERROR "illegal combination" + LDP.P 8(R2), (R2, R3) // ERROR "constrained unpredictable behavior" + LDP.W 8(R3), (R2, R3) // ERROR "constrained unpredictable behavior" + LDP (R1), (R2, R2) // ERROR "constrained unpredictable behavior" + LDP (R0), (F0, F1) // ERROR "invalid register pair" + LDP (R0), (R3, ZR) // ERROR "invalid register pair" + LDXPW (RSP), (R2, R2) // ERROR "constrained unpredictable behavior" + LDAXPW (R5), (R2, R2) // ERROR "constrained unpredictable behavior" MOVD.P 300(R2), R3 // ERROR "offset out of range [-255,254]" MOVD.P R3, 344(R2) // ERROR "offset out of range [-255,254]" MOVD (R3)(R7.SXTX<<2), R8 // ERROR "invalid index shift amount" @@ -16,6 +28,17 @@ TEXT errors(SB),$0 MOVWU (R5)(R4<<1), R10 // ERROR "invalid index shift amount" MOVB (R5)(R4.SXTW<<5), R10 // ERROR "invalid index shift amount" MOVH R5, (R6)(R2<<3) // ERROR "invalid index shift amount" + MADD R1, R2, R3 // ERROR "illegal combination" + MOVD.P R1, 8(R1) // ERROR "constrained unpredictable behavior" + MOVD.W 16(R2), R2 // ERROR "constrained unpredictable behavior" + STP (F2, F3), (R0) // ERROR "invalid register pair" + STP.W (R1, R2), 8(R1) // ERROR "constrained unpredictable behavior" + STP.P (R1, R2), 8(R2) // ERROR "constrained unpredictable behavior" + STLXP (R6, R11), (RSP), R6 // ERROR "constrained unpredictable behavior" + STXP (R6, R11), (R2), R2 // ERROR "constrained unpredictable behavior" + STLXR R3, (RSP), R3 // ERROR "constrained unpredictable behavior" + STXR R3, (R4), R4 // ERROR "constrained unpredictable behavior" + STLXRB R2, (R5), R5 // ERROR "constrained unpredictable behavior" VLD1 (R8)(R13), [V2.B16] // ERROR "illegal combination" VLD1 8(R9), [V2.B16] // ERROR "illegal combination" VST1 [V1.B16], (R8)(R13) // ERROR "illegal combination" @@ -83,15 +106,10 @@ TEXT errors(SB),$0 VST1.P [V1.B16], (R8)(R9<<1) // ERROR "invalid extended register" VREV64 V1.H4, V2.H8 // ERROR "invalid arrangement" VREV64 V1.D1, V2.D1 // ERROR "invalid arrangement" - ADD R1, R2, R3, R4 // ERROR "illegal combination" - MADD R1, R2, R3 // ERROR "illegal combination" - CINC CS, R2, R3, R4 // ERROR "illegal combination" - CSEL LT, R1, R2 // ERROR "illegal combination" - AND $0x22220000, R2, RSP // ERROR "illegal combination" - ANDS $0x22220000, R2, RSP // ERROR "illegal combination" - LDP (R0), (F0, F1) // ERROR "invalid register pair" - LDP (R0), (R3, ZR) // ERROR "invalid register pair" - STP (F2, F3), (R0) // ERROR "invalid register pair" FLDPD (R0), (R1, R2) // ERROR "invalid register pair" + FLDPD (R1), (F2, F2) // ERROR "constrained unpredictable behavior" + FLDPS (R2), (F3, F3) // ERROR "constrained unpredictable behavior" FSTPD (R1, R2), (R0) // ERROR "invalid register pair" + FMOVS (F2), F0 // ERROR "illegal combination" + FMOVD F0, (F1) // ERROR "illegal combination" RET diff --git a/src/cmd/asm/internal/asm/testdata/ppc64.s b/src/cmd/asm/internal/asm/testdata/ppc64.s index ba00b8f6e2..9e8929dac4 100644 --- a/src/cmd/asm/internal/asm/testdata/ppc64.s +++ b/src/cmd/asm/internal/asm/testdata/ppc64.s @@ -550,7 +550,7 @@ label1: // ftsqrt BF, FRB FTSQRT F2,$7 -// FCFID +// FCFID // FCFIDS FCFID F2,F3 diff --git a/src/cmd/compile/fmt_test.go b/src/cmd/compile/fmt_test.go index e28e428a17..65f88dfff9 100644 --- a/src/cmd/compile/fmt_test.go +++ b/src/cmd/compile/fmt_test.go @@ -700,6 +700,7 @@ var knownFormats = map[string]string{ "int8 %x": "", "interface{} %#v": "", "interface{} %T": "", + "interface{} %p": "", "interface{} %q": "", "interface{} %s": "", "interface{} %v": "", diff --git a/src/cmd/compile/internal/amd64/ssa.go b/src/cmd/compile/internal/amd64/ssa.go index ae6141dd12..b4c4b1f4cd 100644 --- a/src/cmd/compile/internal/amd64/ssa.go +++ b/src/cmd/compile/internal/amd64/ssa.go @@ -583,7 +583,11 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.From.Reg = v.Args[0].Reg() p.To.Type = obj.TYPE_CONST p.To.Offset = v.AuxInt - case ssa.OpAMD64BTLconst, ssa.OpAMD64BTQconst: + case ssa.OpAMD64BTLconst, ssa.OpAMD64BTQconst, + ssa.OpAMD64TESTQconst, ssa.OpAMD64TESTLconst, ssa.OpAMD64TESTWconst, ssa.OpAMD64TESTBconst, + ssa.OpAMD64BTSLconst, ssa.OpAMD64BTSQconst, + ssa.OpAMD64BTCLconst, ssa.OpAMD64BTCQconst, + ssa.OpAMD64BTRLconst, ssa.OpAMD64BTRQconst: op := v.Op if op == ssa.OpAMD64BTQconst && v.AuxInt < 32 { // Emit 32-bit version because it's shorter @@ -594,15 +598,6 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.From.Offset = v.AuxInt p.To.Type = obj.TYPE_REG p.To.Reg = v.Args[0].Reg() - case ssa.OpAMD64TESTQconst, ssa.OpAMD64TESTLconst, ssa.OpAMD64TESTWconst, ssa.OpAMD64TESTBconst, - ssa.OpAMD64BTSLconst, ssa.OpAMD64BTSQconst, - ssa.OpAMD64BTCLconst, ssa.OpAMD64BTCQconst, - ssa.OpAMD64BTRLconst, ssa.OpAMD64BTRQconst: - p := s.Prog(v.Op.Asm()) - p.From.Type = obj.TYPE_CONST - p.From.Offset = v.AuxInt - p.To.Type = obj.TYPE_REG - p.To.Reg = v.Args[0].Reg() case ssa.OpAMD64CMPQload, ssa.OpAMD64CMPLload, ssa.OpAMD64CMPWload, ssa.OpAMD64CMPBload: p := s.Prog(v.Op.Asm()) p.From.Type = obj.TYPE_MEM @@ -700,6 +695,7 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.To.Type = obj.TYPE_REG p.To.Reg = v.Reg() case ssa.OpAMD64MOVQstore, ssa.OpAMD64MOVSSstore, ssa.OpAMD64MOVSDstore, ssa.OpAMD64MOVLstore, ssa.OpAMD64MOVWstore, ssa.OpAMD64MOVBstore, ssa.OpAMD64MOVOstore, + ssa.OpAMD64BTCQmodify, ssa.OpAMD64BTCLmodify, ssa.OpAMD64BTRQmodify, ssa.OpAMD64BTRLmodify, ssa.OpAMD64BTSQmodify, ssa.OpAMD64BTSLmodify, ssa.OpAMD64ADDQmodify, ssa.OpAMD64SUBQmodify, ssa.OpAMD64ANDQmodify, ssa.OpAMD64ORQmodify, ssa.OpAMD64XORQmodify, ssa.OpAMD64ADDLmodify, ssa.OpAMD64SUBLmodify, ssa.OpAMD64ANDLmodify, ssa.OpAMD64ORLmodify, ssa.OpAMD64XORLmodify: p := s.Prog(v.Op.Asm()) @@ -764,16 +760,12 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.To.Type = obj.TYPE_MEM p.To.Reg = v.Args[0].Reg() gc.AddAux2(&p.To, v, off) - } else { - p := s.Prog(v.Op.Asm()) - p.From.Type = obj.TYPE_CONST - p.From.Offset = val - p.To.Type = obj.TYPE_MEM - p.To.Reg = v.Args[0].Reg() - gc.AddAux2(&p.To, v, off) + break } + fallthrough case ssa.OpAMD64ANDQconstmodify, ssa.OpAMD64ANDLconstmodify, ssa.OpAMD64ORQconstmodify, ssa.OpAMD64ORLconstmodify, - ssa.OpAMD64XORQconstmodify, ssa.OpAMD64XORLconstmodify: + ssa.OpAMD64BTCQconstmodify, ssa.OpAMD64BTCLconstmodify, ssa.OpAMD64BTSQconstmodify, ssa.OpAMD64BTSLconstmodify, + ssa.OpAMD64BTRQconstmodify, ssa.OpAMD64BTRLconstmodify, ssa.OpAMD64XORQconstmodify, ssa.OpAMD64XORLconstmodify: sc := v.AuxValAndOff() off := sc.Off() val := sc.Val() diff --git a/src/cmd/compile/internal/arm/ssa.go b/src/cmd/compile/internal/arm/ssa.go index 98627344b8..9a8fabf622 100644 --- a/src/cmd/compile/internal/arm/ssa.go +++ b/src/cmd/compile/internal/arm/ssa.go @@ -7,6 +7,7 @@ package arm import ( "fmt" "math" + "math/bits" "cmd/compile/internal/gc" "cmd/compile/internal/ssa" @@ -119,6 +120,28 @@ func genregshift(s *gc.SSAGenState, as obj.As, r0, r1, r2, r int16, typ int64) * return p } +// find a (lsb, width) pair for BFC +// lsb must be in [0, 31], width must be in [1, 32 - lsb] +// return (0xffffffff, 0) if v is not a binary like 0...01...10...0 +func getBFC(v uint32) (uint32, uint32) { + var m, l uint32 + // BFC is not applicable with zero + if v == 0 { + return 0xffffffff, 0 + } + // find the lowest set bit, for example l=2 for 0x3ffffffc + l = uint32(bits.TrailingZeros32(v)) + // m-1 represents the highest set bit index, for example m=30 for 0x3ffffffc + m = 32 - uint32(bits.LeadingZeros32(v)) + // check if v is a binary like 0...01...10...0 + if (1<<m)-(1<<l) == v { + // it must be m > l for non-zero v + return l, m - l + } + // invalid + return 0xffffffff, 0 +} + func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { switch v.Op { case ssa.OpCopy, ssa.OpARMMOVWreg: @@ -267,16 +290,38 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.Reg = v.Args[0].Reg() p.To.Type = obj.TYPE_REG p.To.Reg = v.Reg() + case ssa.OpARMANDconst, ssa.OpARMBICconst: + // try to optimize ANDconst and BICconst to BFC, which saves bytes and ticks + // BFC is only available on ARMv7, and its result and source are in the same register + if objabi.GOARM == 7 && v.Reg() == v.Args[0].Reg() { + var val uint32 + if v.Op == ssa.OpARMANDconst { + val = ^uint32(v.AuxInt) + } else { // BICconst + val = uint32(v.AuxInt) + } + lsb, width := getBFC(val) + // omit BFC for ARM's imm12 + if 8 < width && width < 24 { + p := s.Prog(arm.ABFC) + p.From.Type = obj.TYPE_CONST + p.From.Offset = int64(width) + p.SetFrom3(obj.Addr{Type: obj.TYPE_CONST, Offset: int64(lsb)}) + p.To.Type = obj.TYPE_REG + p.To.Reg = v.Reg() + break + } + } + // fall back to ordinary form + fallthrough case ssa.OpARMADDconst, ssa.OpARMADCconst, ssa.OpARMSUBconst, ssa.OpARMSBCconst, ssa.OpARMRSBconst, ssa.OpARMRSCconst, - ssa.OpARMANDconst, ssa.OpARMORconst, ssa.OpARMXORconst, - ssa.OpARMBICconst, ssa.OpARMSLLconst, ssa.OpARMSRLconst, ssa.OpARMSRAconst: diff --git a/src/cmd/compile/internal/arm64/ssa.go b/src/cmd/compile/internal/arm64/ssa.go index db7064cff0..87703dd80d 100644 --- a/src/cmd/compile/internal/arm64/ssa.go +++ b/src/cmd/compile/internal/arm64/ssa.go @@ -195,7 +195,9 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { ssa.OpARM64FNMULS, ssa.OpARM64FNMULD, ssa.OpARM64FDIVS, - ssa.OpARM64FDIVD: + ssa.OpARM64FDIVD, + ssa.OpARM64ROR, + ssa.OpARM64RORW: r := v.Reg() r1 := v.Args[0].Reg() r2 := v.Args[1].Reg() @@ -253,6 +255,12 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.Reg = v.Args[1].Reg() p.To.Type = obj.TYPE_REG p.To.Reg = v.Reg() + case ssa.OpARM64MVNshiftLL, ssa.OpARM64NEGshiftLL: + genshift(s, v.Op.Asm(), 0, v.Args[0].Reg(), v.Reg(), arm64.SHIFT_LL, v.AuxInt) + case ssa.OpARM64MVNshiftRL, ssa.OpARM64NEGshiftRL: + genshift(s, v.Op.Asm(), 0, v.Args[0].Reg(), v.Reg(), arm64.SHIFT_LR, v.AuxInt) + case ssa.OpARM64MVNshiftRA, ssa.OpARM64NEGshiftRA: + genshift(s, v.Op.Asm(), 0, v.Args[0].Reg(), v.Reg(), arm64.SHIFT_AR, v.AuxInt) case ssa.OpARM64ADDshiftLL, ssa.OpARM64SUBshiftLL, ssa.OpARM64ANDshiftLL, @@ -315,11 +323,11 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.From.Type = obj.TYPE_CONST p.From.Offset = v.AuxInt p.Reg = v.Args[0].Reg() - case ssa.OpARM64CMPshiftLL: + case ssa.OpARM64CMPshiftLL, ssa.OpARM64CMNshiftLL, ssa.OpARM64TSTshiftLL: genshift(s, v.Op.Asm(), v.Args[0].Reg(), v.Args[1].Reg(), 0, arm64.SHIFT_LL, v.AuxInt) - case ssa.OpARM64CMPshiftRL: + case ssa.OpARM64CMPshiftRL, ssa.OpARM64CMNshiftRL, ssa.OpARM64TSTshiftRL: genshift(s, v.Op.Asm(), v.Args[0].Reg(), v.Args[1].Reg(), 0, arm64.SHIFT_LR, v.AuxInt) - case ssa.OpARM64CMPshiftRA: + case ssa.OpARM64CMPshiftRA, ssa.OpARM64CMNshiftRA, ssa.OpARM64TSTshiftRA: genshift(s, v.Op.Asm(), v.Args[0].Reg(), v.Args[1].Reg(), 0, arm64.SHIFT_AR, v.AuxInt) case ssa.OpARM64MOVDaddr: p := s.Prog(arm64.AMOVD) @@ -696,8 +704,11 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { fallthrough case ssa.OpARM64MVN, ssa.OpARM64NEG, + ssa.OpARM64FABSD, ssa.OpARM64FMOVDfpgp, ssa.OpARM64FMOVDgpfp, + ssa.OpARM64FMOVSfpgp, + ssa.OpARM64FMOVSgpfp, ssa.OpARM64FNEGS, ssa.OpARM64FNEGD, ssa.OpARM64FSQRTD, @@ -728,6 +739,7 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { ssa.OpARM64CLZW, ssa.OpARM64FRINTAD, ssa.OpARM64FRINTMD, + ssa.OpARM64FRINTND, ssa.OpARM64FRINTPD, ssa.OpARM64FRINTZD: p := s.Prog(v.Op.Asm()) diff --git a/src/cmd/compile/internal/gc/bexport.go b/src/cmd/compile/internal/gc/bexport.go index d0b1804eb6..3ef1e6af4d 100644 --- a/src/cmd/compile/internal/gc/bexport.go +++ b/src/cmd/compile/internal/gc/bexport.go @@ -2,444 +2,14 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// Binary package export. - -/* -1) Export data encoding principles: - -The export data is a serialized description of the graph of exported -"objects": constants, types, variables, and functions. Aliases may be -directly reexported, and unaliased types may be indirectly reexported -(as part of the type of a directly exported object). More generally, -objects referred to from inlined function bodies can be reexported. -We need to know which package declares these reexported objects, and -therefore packages are also part of the export graph. - -The roots of the graph are two lists of objects. The 1st list (phase 1, -see Export) contains all objects that are exported at the package level. -These objects are the full representation of the package's API, and they -are the only information a platform-independent tool (e.g., go/types) -needs to know to type-check against a package. - -The 2nd list of objects contains all objects referred to from exported -inlined function bodies. These objects are needed by the compiler to -make sense of the function bodies; the exact list contents are compiler- -specific. - -Finally, the export data contains a list of representations for inlined -function bodies. The format of this representation is compiler specific. - -The graph is serialized in in-order fashion, starting with the roots. -Each object in the graph is serialized by writing its fields sequentially. -If the field is a pointer to another object, that object is serialized in -place, recursively. Otherwise the field is written in place. Non-pointer -fields are all encoded as integer or string values. - -Some objects (packages, types) may be referred to more than once. When -reaching an object that was not serialized before, an integer _index_ -is assigned to it, starting at 0. In this case, the encoding starts -with an integer _tag_ < 0. The tag value indicates the kind of object -that follows and that this is the first time that we see this object. -If the object was already serialized, the encoding is simply the object -index >= 0. An importer can trivially determine if an object needs to -be read in for the first time (tag < 0) and entered into the respective -object table, or if the object was seen already (index >= 0), in which -case the index is used to look up the object in the respective table. - -Before exporting or importing, the type tables are populated with the -predeclared types (int, string, error, unsafe.Pointer, etc.). This way -they are automatically encoded with a known and fixed type index. - -2) Encoding format: - -The export data starts with two newline-terminated strings: a version -string and either an empty string, or "debug", when emitting the debug -format. These strings are followed by version-specific encoding options. - -(The Go1.7 version starts with a couple of bytes specifying the format. -That format encoding is no longer used but is supported to avoid spurious -errors when importing old installed package files.) - -This header is followed by the package object for the exported package, -two lists of objects, and the list of inlined function bodies. - -The encoding of objects is straight-forward: Constants, variables, and -functions start with their name, type, and possibly a value. Named types -record their name and package so that they can be canonicalized: If the -same type was imported before via another import, the importer must use -the previously imported type pointer so that we have exactly one version -(i.e., one pointer) for each named type (and read but discard the current -type encoding). Unnamed types simply encode their respective fields. -Aliases are encoded starting with their name followed by the qualified -identifier denoting the original (aliased) object, which was exported -earlier. - -In the encoding, some lists start with the list length. Some lists are -terminated with an end marker (usually for lists where we may not know -the length a priori). - -Integers use variable-length encoding for compact representation. - -Strings are canonicalized similar to objects that may occur multiple times: -If the string was exported already, it is represented by its index only. -Otherwise, the export data starts with the negative string length (negative, -so we can distinguish from string index), followed by the string bytes. -The empty string is mapped to index 0. (The initial format string is an -exception; it is encoded as the string bytes followed by a newline). - -The exporter and importer are completely symmetric in implementation: For -each encoding routine there is a matching and symmetric decoding routine. -This symmetry makes it very easy to change or extend the format: If a new -field needs to be encoded, a symmetric change can be made to exporter and -importer. - -3) Making changes to the encoding format: - -Any change to the encoding format requires a respective change in the -exporter below and a corresponding symmetric change to the importer in -bimport.go. - -Furthermore, it requires a corresponding change to go/internal/gcimporter -and golang.org/x/tools/go/gcimporter15. Changes to the latter must preserve -compatibility with both the last release of the compiler, and with the -corresponding compiler at tip. That change is necessarily more involved, -as it must switch based on the version number in the export data file. - -It is recommended to turn on debugFormat temporarily when working on format -changes as it will help finding encoding/decoding inconsistencies quickly. -*/ - package gc import ( - "bufio" - "bytes" "cmd/compile/internal/types" - "cmd/internal/src" - "encoding/binary" - "fmt" - "math/big" - "sort" - "strings" ) -// If debugFormat is set, each integer and string value is preceded by a marker -// and position information in the encoding. This mechanism permits an importer -// to recognize immediately when it is out of sync. The importer recognizes this -// mode automatically (i.e., it can import export data produced with debugging -// support even if debugFormat is not set at the time of import). This mode will -// lead to massively larger export data (by a factor of 2 to 3) and should only -// be enabled during development and debugging. -// -// NOTE: This flag is the first flag to enable if importing dies because of -// (suspected) format errors, and whenever a change is made to the format. -const debugFormat = false // default: false - -// Current export format version. Increase with each format change. -// 6: package height (CL 105038) -// 5: improved position encoding efficiency (issue 20080, CL 41619) -// 4: type name objects support type aliases, uses aliasTag -// 3: Go1.8 encoding (same as version 2, aliasTag defined but never used) -// 2: removed unused bool in ODCL export (compiler only) -// 1: header format change (more regular), export package for _ struct fields -// 0: Go1.7 encoding -const exportVersion = 6 - -// exportInlined enables the export of inlined function bodies and related -// dependencies. The compiler should work w/o any loss of functionality with -// the flag disabled, but the generated code will lose access to inlined -// function bodies across packages, leading to performance bugs. -// Leave for debugging. -const exportInlined = true // default: true - -// trackAllTypes enables cycle tracking for all types, not just named -// types. The existing compiler invariants assume that unnamed types -// that are not completely set up are not used, or else there are spurious -// errors. -// If disabled, only named types are tracked, possibly leading to slightly -// less efficient encoding in rare cases. It also prevents the export of -// some corner-case type declarations (but those were not handled correctly -// with the former textual export format either). -// Note that when a type is only seen once, as many unnamed types are, -// it is less efficient to track it, since we then also record an index for it. -// See CLs 41622 and 41623 for some data and discussion. -// TODO(gri) enable selectively and remove once issues caused by it are fixed -const trackAllTypes = false - type exporter struct { - out *bufio.Writer - - // object -> index maps, indexed in order of serialization - strIndex map[string]int - pathIndex map[string]int - pkgIndex map[*types.Pkg]int - typIndex map[*types.Type]int - funcList []*Func - marked map[*types.Type]bool // types already seen by markType - - // position encoding - posInfoFormat bool - prevFile string - prevLine int - - // debugging support - written int // bytes written - indent int // for p.trace - trace bool -} - -// export writes the exportlist for localpkg to out and returns the number of bytes written. -func export(out *bufio.Writer, trace bool) int { - p := exporter{ - out: out, - strIndex: map[string]int{"": 0}, // empty string is mapped to 0 - pathIndex: map[string]int{"": 0}, // empty path is mapped to 0 - pkgIndex: make(map[*types.Pkg]int), - typIndex: make(map[*types.Type]int), - posInfoFormat: true, - trace: trace, - } - - // write version info - // The version string must start with "version %d" where %d is the version - // number. Additional debugging information may follow after a blank; that - // text is ignored by the importer. - p.rawStringln(fmt.Sprintf("version %d", exportVersion)) - var debug string - if debugFormat { - debug = "debug" - } - p.rawStringln(debug) // cannot use p.bool since it's affected by debugFormat; also want to see this clearly - p.bool(trackAllTypes) - p.bool(p.posInfoFormat) - - // --- generic export data --- - - // populate type map with predeclared "known" types - predecl := predeclared() - for index, typ := range predecl { - p.typIndex[typ] = index - } - if len(p.typIndex) != len(predecl) { - Fatalf("exporter: duplicate entries in type map?") - } - - // write package data - if localpkg.Path != "" { - Fatalf("exporter: local package path not empty: %q", localpkg.Path) - } - p.pkg(localpkg) - if p.trace { - p.tracef("\n") - } - - // export objects - // - // We've already added all exported (package-level) objects to - // exportlist. These objects represent all information - // required to import this package and type-check against it; - // i.e., this is the platform-independent export data. The - // format is generic in the sense that different compilers can - // use the same representation. - // - // However, due to inlineable function and their dependencies, - // we may need to export (or possibly reexport) additional - // objects. We handle these objects separately. This data is - // platform-specific as it depends on the inlining decisions - // of the compiler and the representation of the inlined - // function bodies. - - // Remember initial exportlist length. - numglobals := len(exportlist) - - // Phase 0: Mark all inlineable functions that an importing - // package could call. This is done by tracking down all - // inlineable methods reachable from exported declarations. - // - // Along the way, we add to exportlist any function and - // variable declarations needed by the inline bodies. - if exportInlined { - p.marked = make(map[*types.Type]bool) - for _, n := range exportlist { - sym := n.Sym - p.markType(asNode(sym.Def).Type) - } - p.marked = nil - } - - // Phase 1: Export package-level objects. - objcount := 0 - for _, n := range exportlist[:numglobals] { - sym := n.Sym - - // TODO(gri) Closures have dots in their names; - // e.g., TestFloatZeroValue.func1 in math/big tests. - if strings.Contains(sym.Name, ".") { - Fatalf("exporter: unexpected symbol: %v", sym) - } - - if sym.Def == nil { - Fatalf("exporter: unknown export symbol: %v", sym) - } - - // TODO(gri) Optimization: Probably worthwhile collecting - // long runs of constants and export them "in bulk" (saving - // tags and types, and making import faster). - - if p.trace { - p.tracef("\n") - } - p.obj(sym) - objcount++ - } - - // indicate end of list - if p.trace { - p.tracef("\n") - } - p.tag(endTag) - - // for self-verification only (redundant) - p.int(objcount) - - // --- compiler-specific export data --- - - if p.trace { - p.tracef("\n--- compiler-specific export data ---\n[ ") - if p.indent != 0 { - Fatalf("exporter: incorrect indentation") - } - } - - // write compiler-specific flags - if p.trace { - p.tracef("\n") - } - - // Phase 2: Export objects added to exportlist during phase 0. - objcount = 0 - for _, n := range exportlist[numglobals:] { - sym := n.Sym - - // TODO(gri) The rest of this loop body is identical with - // the loop body above. Leave alone for now since there - // are different optimization opportunities, but factor - // eventually. - - // TODO(gri) Closures have dots in their names; - // e.g., TestFloatZeroValue.func1 in math/big tests. - if strings.Contains(sym.Name, ".") { - Fatalf("exporter: unexpected symbol: %v", sym) - } - - if sym.Def == nil { - Fatalf("exporter: unknown export symbol: %v", sym) - } - - // TODO(gri) Optimization: Probably worthwhile collecting - // long runs of constants and export them "in bulk" (saving - // tags and types, and making import faster). - - if p.trace { - p.tracef("\n") - } - - if IsAlias(sym) { - Fatalf("exporter: unexpected type alias %v in inlined function body", sym) - } - - p.obj(sym) - objcount++ - } - - // indicate end of list - if p.trace { - p.tracef("\n") - } - p.tag(endTag) - - // for self-verification only (redundant) - p.int(objcount) - - // --- inlined function bodies --- - - if p.trace { - p.tracef("\n--- inlined function bodies ---\n") - if p.indent != 0 { - Fatalf("exporter: incorrect indentation") - } - } - - // write inlineable function bodies - // Don't use range since funcList may grow. - objcount = 0 - for i := 0; i < len(p.funcList); i++ { - if f := p.funcList[i]; f.ExportInline() { - // function has inlineable body: - // write index and body - if p.trace { - p.tracef("\n----\nfunc { %#v }\n", asNodes(f.Inl.Body)) - } - p.int(i) - p.int(int(f.Inl.Cost)) - p.stmtList(asNodes(f.Inl.Body)) - if p.trace { - p.tracef("\n") - } - objcount++ - } - } - - // indicate end of list - if p.trace { - p.tracef("\n") - } - p.int(-1) // invalid index terminates list - - // for self-verification only (redundant) - p.int(objcount) - - if p.trace { - p.tracef("\n--- end ---\n") - } - - // --- end of export data --- - - return p.written -} - -func (p *exporter) pkg(pkg *types.Pkg) { - if pkg == nil { - Fatalf("exporter: unexpected nil pkg") - } - - // if we saw the package before, write its index (>= 0) - if i, ok := p.pkgIndex[pkg]; ok { - p.index('P', i) - return - } - - // otherwise, remember the package, write the package tag (< 0) and package data - if p.trace { - p.tracef("P%d = { ", len(p.pkgIndex)) - defer p.tracef("} ") - } - p.pkgIndex[pkg] = len(p.pkgIndex) - - p.tag(packageTag) - p.string(pkg.Name) - p.path(pkg.Path) - p.int(pkg.Height) -} - -func unidealType(typ *types.Type, val Val) *types.Type { - // Untyped (ideal) constants get their own type. This decouples - // the constant type from the encoding of the constant value. - if typ == nil || typ.IsUntyped() { - typ = untype(val.Ctype()) - } - return typ } // markType recursively visits types reachable from t to identify @@ -508,1287 +78,11 @@ func (p *exporter) markType(t *types.Type) { } } -func (p *exporter) obj(sym *types.Sym) { - // Exported objects may be from different packages because they - // may be re-exported via an exported alias or as dependencies in - // exported inlined function bodies. Thus, exported object names - // must be fully qualified. - // - // (This can only happen for aliased objects or during phase 2 - // (exportInlined enabled) of object export. Unaliased Objects - // exported in phase 1 (compiler-indendepent objects) are by - // definition only the objects from the current package and not - // pulled in via inlined function bodies. In that case the package - // qualifier is not needed. Possible space optimization.) - - n := asNode(sym.Def) - switch n.Op { - case OLITERAL: - // constant - // TODO(gri) determine if we need the typecheck call here - n = typecheck(n, Erv) - if n == nil || n.Op != OLITERAL { - Fatalf("exporter: dumpexportconst: oconst nil: %v", sym) - } - - p.tag(constTag) - p.pos(n.Pos) - // TODO(gri) In inlined functions, constants are used directly - // so they should never occur as re-exported objects. We may - // not need the qualified name here. See also comment above. - // Possible space optimization. - p.qualifiedName(sym) - p.typ(unidealType(n.Type, n.Val())) - p.value(n.Val()) - - case OTYPE: - // named type - t := n.Type - if t.Etype == TFORW { - Fatalf("exporter: export of incomplete type %v", sym) - } - - if IsAlias(sym) { - p.tag(aliasTag) - p.pos(n.Pos) - p.qualifiedName(sym) - } else { - p.tag(typeTag) - } - p.typ(t) - - case ONAME: - // variable or function - n = typecheck(n, Erv|Ecall) - if n == nil || n.Type == nil { - Fatalf("exporter: variable/function exported but not defined: %v", sym) - } - - if n.Type.Etype == TFUNC && n.Class() == PFUNC { - // function - p.tag(funcTag) - p.pos(n.Pos) - p.qualifiedName(sym) - - sig := asNode(sym.Def).Type - - // Theoretically, we only need numbered - // parameters if we're supplying an inline - // function body. However, it's possible to - // import a function from a package that - // didn't supply the inline body, and then - // another that did. In this case, we would - // need to rename the parameters during - // import, which is a little sketchy. - // - // For simplicity, just always number - // parameters. - p.paramList(sig.Params(), true) - p.paramList(sig.Results(), true) - - p.funcList = append(p.funcList, asNode(sym.Def).Func) - } else { - // variable - p.tag(varTag) - p.pos(n.Pos) - p.qualifiedName(sym) - p.typ(asNode(sym.Def).Type) - } - - default: - Fatalf("exporter: unexpected export symbol: %v %v", n.Op, sym) - } -} - // deltaNewFile is a magic line delta offset indicating a new file. // We use -64 because it is rare; see issue 20080 and CL 41619. // -64 is the smallest int that fits in a single byte as a varint. const deltaNewFile = -64 -func (p *exporter) pos(pos src.XPos) { - if !p.posInfoFormat { - return - } - - file, line := fileLine(pos) - if file == p.prevFile { - // common case: write line delta - // delta == deltaNewFile means different file - // if the actual line delta is deltaNewFile, - // follow up with a negative int to indicate that. - // only non-negative ints can follow deltaNewFile - // when writing a new file. - delta := line - p.prevLine - p.int(delta) - if delta == deltaNewFile { - p.int(-1) // -1 means no file change - } - } else { - // different file - p.int(deltaNewFile) - p.int(line) // line >= 0 - p.path(file) - p.prevFile = file - } - p.prevLine = line -} - -func (p *exporter) path(s string) { - if i, ok := p.pathIndex[s]; ok { - // Note: Using p.index(i) here requires the use of p.tag(-len(c)) below - // to get matching debug markers ('t'). But in trace mode p.tag - // assumes that the tag argument is a valid tag that can be looked - // up in the tagString list, rather then some arbitrary slice length. - // Use p.int instead. - p.int(i) // i >= 0 - return - } - p.pathIndex[s] = len(p.pathIndex) - c := strings.Split(s, "/") - p.int(-len(c)) // -len(c) < 0 - for _, x := range c { - p.string(x) - } -} - -func fileLine(pos0 src.XPos) (file string, line int) { - pos := Ctxt.PosTable.Pos(pos0) - file = pos.Base().AbsFilename() - line = int(pos.RelLine()) - return -} - -func (p *exporter) typ(t *types.Type) { - if t == nil { - Fatalf("exporter: nil type") - } - - // Possible optimization: Anonymous pointer types *T where - // T is a named type are common. We could canonicalize all - // such types *T to a single type PT = *T. This would lead - // to at most one *T entry in typIndex, and all future *T's - // would be encoded as the respective index directly. Would - // save 1 byte (pointerTag) per *T and reduce the typIndex - // size (at the cost of a canonicalization map). We can do - // this later, without encoding format change. - - // if we saw the type before, write its index (>= 0) - if i, ok := p.typIndex[t]; ok { - p.index('T', i) - return - } - - // otherwise, remember the type, write the type tag (< 0) and type data - if trackAllTypes { - if p.trace { - p.tracef("T%d = {>\n", len(p.typIndex)) - defer p.tracef("<\n} ") - } - p.typIndex[t] = len(p.typIndex) - } - - // pick off named types - if tsym := t.Sym; tsym != nil { - if !trackAllTypes { - // if we don't track all types, track named types now - p.typIndex[t] = len(p.typIndex) - } - - // Predeclared types should have been found in the type map. - if t.Orig == t { - Fatalf("exporter: predeclared type missing from type map?") - } - - n := typenod(t) - if n.Type != t { - Fatalf("exporter: named type definition incorrectly set up") - } - - p.tag(namedTag) - p.pos(n.Pos) - p.qualifiedName(tsym) - - // write underlying type - p.typ(t.Orig) - - // interfaces don't have associated methods - if t.Orig.IsInterface() { - return - } - - // sort methods for reproducible export format - // TODO(gri) Determine if they are already sorted - // in which case we can drop this step. - var methods []*types.Field - methods = append(methods, t.Methods().Slice()...) - sort.Sort(methodbyname(methods)) - p.int(len(methods)) - - if p.trace && len(methods) > 0 { - p.tracef("associated methods {>") - } - - for _, m := range methods { - if p.trace { - p.tracef("\n") - } - if strings.Contains(m.Sym.Name, ".") { - Fatalf("invalid symbol name: %s (%v)", m.Sym.Name, m.Sym) - } - - p.pos(m.Pos) - p.fieldSym(m.Sym, false) - - sig := m.Type - mfn := asNode(sig.FuncType().Nname) - - // See comment in (*exporter).obj about - // numbered parameters. - p.paramList(sig.Recvs(), true) - p.paramList(sig.Params(), true) - p.paramList(sig.Results(), true) - p.bool(m.Nointerface()) // record go:nointerface pragma value (see also #16243) - - p.funcList = append(p.funcList, mfn.Func) - } - - if p.trace && len(methods) > 0 { - p.tracef("<\n} ") - } - - return - } - - // otherwise we have a type literal - switch t.Etype { - case TARRAY: - if t.IsDDDArray() { - Fatalf("array bounds should be known at export time: %v", t) - } - p.tag(arrayTag) - p.int64(t.NumElem()) - p.typ(t.Elem()) - - case TSLICE: - p.tag(sliceTag) - p.typ(t.Elem()) - - case TDDDFIELD: - // see p.param use of TDDDFIELD - p.tag(dddTag) - p.typ(t.DDDField()) - - case TSTRUCT: - p.tag(structTag) - p.fieldList(t) - - case TPTR32, TPTR64: // could use Tptr but these are constants - p.tag(pointerTag) - p.typ(t.Elem()) - - case TFUNC: - p.tag(signatureTag) - p.paramList(t.Params(), false) - p.paramList(t.Results(), false) - - case TINTER: - p.tag(interfaceTag) - p.methodList(t) - - case TMAP: - p.tag(mapTag) - p.typ(t.Key()) - p.typ(t.Elem()) - - case TCHAN: - p.tag(chanTag) - p.int(int(t.ChanDir())) - p.typ(t.Elem()) - - default: - Fatalf("exporter: unexpected type: %v (Etype = %d)", t, t.Etype) - } -} - -func (p *exporter) qualifiedName(sym *types.Sym) { - p.string(sym.Name) - p.pkg(sym.Pkg) -} - -func (p *exporter) fieldList(t *types.Type) { - if p.trace && t.NumFields() > 0 { - p.tracef("fields {>") - defer p.tracef("<\n} ") - } - - p.int(t.NumFields()) - for _, f := range t.Fields().Slice() { - if p.trace { - p.tracef("\n") - } - p.field(f) - } -} - -func (p *exporter) field(f *types.Field) { - p.pos(f.Pos) - p.fieldName(f) - p.typ(f.Type) - p.string(f.Note) -} - -func (p *exporter) methodList(t *types.Type) { - var embeddeds, methods []*types.Field - - for _, m := range t.Methods().Slice() { - if m.Sym != nil { - methods = append(methods, m) - } else { - embeddeds = append(embeddeds, m) - } - } - - if p.trace && len(embeddeds) > 0 { - p.tracef("embeddeds {>") - } - p.int(len(embeddeds)) - for _, m := range embeddeds { - if p.trace { - p.tracef("\n") - } - p.pos(m.Pos) - p.typ(m.Type) - } - if p.trace && len(embeddeds) > 0 { - p.tracef("<\n} ") - } - - if p.trace && len(methods) > 0 { - p.tracef("methods {>") - } - p.int(len(methods)) - for _, m := range methods { - if p.trace { - p.tracef("\n") - } - p.method(m) - } - if p.trace && len(methods) > 0 { - p.tracef("<\n} ") - } -} - -func (p *exporter) method(m *types.Field) { - p.pos(m.Pos) - p.methodName(m.Sym) - p.paramList(m.Type.Params(), false) - p.paramList(m.Type.Results(), false) -} - -func (p *exporter) fieldName(t *types.Field) { - name := t.Sym.Name - if t.Embedded != 0 { - // anonymous field - we distinguish between 3 cases: - // 1) field name matches base type name and is exported - // 2) field name matches base type name and is not exported - // 3) field name doesn't match base type name (alias name) - bname := basetypeName(t.Type) - if name == bname { - if types.IsExported(name) { - name = "" // 1) we don't need to know the field name or package - } else { - name = "?" // 2) use unexported name "?" to force package export - } - } else { - // 3) indicate alias and export name as is - // (this requires an extra "@" but this is a rare case) - p.string("@") - } - } - p.string(name) - if name != "" && !types.IsExported(name) { - p.pkg(t.Sym.Pkg) - } -} - -// methodName is like qualifiedName but it doesn't record the package for exported names. -func (p *exporter) methodName(sym *types.Sym) { - p.string(sym.Name) - if !types.IsExported(sym.Name) { - p.pkg(sym.Pkg) - } -} - -func basetypeName(t *types.Type) string { - s := t.Sym - if s == nil && t.IsPtr() { - s = t.Elem().Sym // deref - } - if s != nil { - return s.Name - } - return "" // unnamed type -} - -func (p *exporter) paramList(params *types.Type, numbered bool) { - if !params.IsFuncArgStruct() { - Fatalf("exporter: parameter list expected") - } - - // use negative length to indicate unnamed parameters - // (look at the first parameter only since either all - // names are present or all are absent) - // - // TODO(gri) If we don't have an exported function - // body, the parameter names are irrelevant for the - // compiler (though they may be of use for other tools). - // Possible space optimization. - n := params.NumFields() - if n > 0 && parName(params.Field(0), numbered) == "" { - n = -n - } - p.int(n) - for _, q := range params.Fields().Slice() { - p.param(q, n, numbered) - } -} - -func (p *exporter) param(q *types.Field, n int, numbered bool) { - t := q.Type - if q.Isddd() { - // create a fake type to encode ... just for the p.typ call - t = types.NewDDDField(t.Elem()) - } - p.typ(t) - if n > 0 { - name := parName(q, numbered) - if name == "" { - // Sometimes we see an empty name even for n > 0. - // This appears to happen for interface methods - // with _ (blank) parameter names. Make sure we - // have a proper name and package so we don't crash - // during import (see also issue #15470). - // (parName uses "" instead of "?" as in fmt.go) - // TODO(gri) review parameter name encoding - name = "_" - } - p.string(name) - if name != "_" { - // Because of (re-)exported inlined functions - // the importpkg may not be the package to which this - // function (and thus its parameter) belongs. We need to - // supply the parameter package here. We need the package - // when the function is inlined so we can properly resolve - // the name. The _ (blank) parameter cannot be accessed, so - // we don't need to export a package. - // - // TODO(gri) This is compiler-specific. Try using importpkg - // here and then update the symbols if we find an inlined - // body only. Otherwise, the parameter name is ignored and - // the package doesn't matter. This would remove an int - // (likely 1 byte) for each named parameter. - p.pkg(q.Sym.Pkg) - } - } - // TODO(gri) This is compiler-specific (escape info). - // Move into compiler-specific section eventually? - // (Not having escape info causes tests to fail, e.g. runtime GCInfoTest) - p.string(q.Note) -} - -func parName(f *types.Field, numbered bool) string { - s := origSym(f.Sym) - if s == nil { - return "" - } - - if s.Name == "_" { - return "_" - } - - // print symbol with Vargen number or not as desired - name := s.Name - if strings.Contains(name, ".") { - Fatalf("invalid symbol name: %s", name) - } - - // Functions that can be inlined use numbered parameters so we can distinguish them - // from other names in their context after inlining (i.e., the parameter numbering - // is a form of parameter rewriting). See issue 4326 for an example and test case. - if numbered { - if n := asNode(f.Nname); !strings.Contains(name, "·") && n != nil && n.Name.Vargen > 0 { - name = fmt.Sprintf("%s·%d", name, n.Name.Vargen) // append Vargen - } - } else { - if i := strings.Index(name, "·"); i > 0 { - name = name[:i] // cut off Vargen - } - } - return name -} - -func (p *exporter) value(x Val) { - if p.trace { - p.tracef("= ") - } - - switch x := x.U.(type) { - case bool: - tag := falseTag - if x { - tag = trueTag - } - p.tag(tag) - - case *Mpint: - if minintval[TINT64].Cmp(x) <= 0 && x.Cmp(maxintval[TINT64]) <= 0 { - // common case: x fits into an int64 - use compact encoding - p.tag(int64Tag) - p.int64(x.Int64()) - return - } - // uncommon case: large x - use float encoding - // (powers of 2 will be encoded efficiently with exponent) - f := newMpflt() - f.SetInt(x) - p.tag(floatTag) - p.float(f) - - case *Mpflt: - p.tag(floatTag) - p.float(x) - - case *Mpcplx: - p.tag(complexTag) - p.float(&x.Real) - p.float(&x.Imag) - - case string: - p.tag(stringTag) - p.string(x) - - case *NilVal: - // not a constant but used in exported function bodies - p.tag(nilTag) - - default: - Fatalf("exporter: unexpected value %v (%T)", x, x) - } -} - -func (p *exporter) float(x *Mpflt) { - // extract sign (there is no -0) - f := &x.Val - sign := f.Sign() - if sign == 0 { - // x == 0 - p.int(0) - return - } - // x != 0 - - // extract exponent such that 0.5 <= m < 1.0 - var m big.Float - exp := f.MantExp(&m) - - // extract mantissa as *big.Int - // - set exponent large enough so mant satisfies mant.IsInt() - // - get *big.Int from mant - m.SetMantExp(&m, int(m.MinPrec())) - mant, acc := m.Int(nil) - if acc != big.Exact { - Fatalf("exporter: internal error") - } - - p.int(sign) - p.int(exp) - p.string(string(mant.Bytes())) -} - -// ---------------------------------------------------------------------------- -// Inlined function bodies - -// Approach: More or less closely follow what fmt.go is doing for FExp mode -// but instead of emitting the information textually, emit the node tree in -// binary form. - -// TODO(gri) Improve tracing output. The current format is difficult to read. - -// stmtList may emit more (or fewer) than len(list) nodes. -func (p *exporter) stmtList(list Nodes) { - if p.trace { - if list.Len() == 0 { - p.tracef("{}") - } else { - p.tracef("{>") - defer p.tracef("<\n}") - } - } - - for _, n := range list.Slice() { - if p.trace { - p.tracef("\n") - } - // TODO inlining produces expressions with ninits. we can't export these yet. - // (from fmt.go:1461ff) - p.node(n) - } - - p.op(OEND) -} - -func (p *exporter) node(n *Node) { - if opprec[n.Op] < 0 { - p.stmt(n) - } else { - p.expr(n) - } -} - -func (p *exporter) exprList(list Nodes) { - if p.trace { - if list.Len() == 0 { - p.tracef("{}") - } else { - p.tracef("{>") - defer p.tracef("<\n}") - } - } - - for _, n := range list.Slice() { - if p.trace { - p.tracef("\n") - } - p.expr(n) - } - - p.op(OEND) -} - -func (p *exporter) elemList(list Nodes) { - if p.trace { - p.tracef("[ ") - } - p.int(list.Len()) - if p.trace { - if list.Len() == 0 { - p.tracef("] {}") - } else { - p.tracef("] {>") - defer p.tracef("<\n}") - } - } - - for _, n := range list.Slice() { - if p.trace { - p.tracef("\n") - } - p.fieldSym(n.Sym, false) - p.expr(n.Left) - } -} - -func (p *exporter) expr(n *Node) { - if p.trace { - p.tracef("( ") - defer p.tracef(") ") - } - - // from nodefmt (fmt.go) - // - // nodefmt reverts nodes back to their original - we don't need to do - // it because we are not bound to produce valid Go syntax when exporting - // - // if (fmtmode != FExp || n.Op != OLITERAL) && n.Orig != nil { - // n = n.Orig - // } - - // from exprfmt (fmt.go) - for n != nil && n.Implicit() && (n.Op == OIND || n.Op == OADDR) { - n = n.Left - } - - switch op := n.Op; op { - // expressions - // (somewhat closely following the structure of exprfmt in fmt.go) - case OPAREN: - p.expr(n.Left) // unparen - - // case ODDDARG: - // unimplemented - handled by default case - - case OLITERAL: - if n.Val().Ctype() == CTNIL && n.Orig != nil && n.Orig != n { - p.expr(n.Orig) - break - } - p.op(OLITERAL) - p.pos(n.Pos) - p.typ(unidealType(n.Type, n.Val())) - p.value(n.Val()) - - case ONAME: - // Special case: explicit name of func (*T) method(...) is turned into pkg.(*T).method, - // but for export, this should be rendered as (*pkg.T).meth. - // These nodes have the special property that they are names with a left OTYPE and a right ONAME. - if n.isMethodExpression() { - p.op(OXDOT) - p.pos(n.Pos) - p.expr(n.Left) // n.Left.Op == OTYPE - p.fieldSym(n.Right.Sym, true) - break - } - - p.op(ONAME) - p.pos(n.Pos) - p.sym(n) - - // case OPACK, ONONAME: - // should have been resolved by typechecking - handled by default case - - case OTYPE: - p.op(OTYPE) - p.pos(n.Pos) - p.typ(n.Type) - - // case OTARRAY, OTMAP, OTCHAN, OTSTRUCT, OTINTER, OTFUNC: - // should have been resolved by typechecking - handled by default case - - // case OCLOSURE: - // unimplemented - handled by default case - - // case OCOMPLIT: - // should have been resolved by typechecking - handled by default case - - case OPTRLIT: - p.op(OPTRLIT) - p.pos(n.Pos) - p.expr(n.Left) - p.bool(n.Implicit()) - - case OSTRUCTLIT: - p.op(OSTRUCTLIT) - p.pos(n.Pos) - p.typ(n.Type) - p.elemList(n.List) // special handling of field names - - case OARRAYLIT, OSLICELIT, OMAPLIT: - p.op(OCOMPLIT) - p.pos(n.Pos) - p.typ(n.Type) - p.exprList(n.List) - - case OKEY: - p.op(OKEY) - p.pos(n.Pos) - p.exprsOrNil(n.Left, n.Right) - - // case OSTRUCTKEY: - // unreachable - handled in case OSTRUCTLIT by elemList - - // case OCALLPART: - // unimplemented - handled by default case - - case OXDOT, ODOT, ODOTPTR, ODOTINTER, ODOTMETH: - p.op(OXDOT) - p.pos(n.Pos) - p.expr(n.Left) - p.fieldSym(n.Sym, true) - - case ODOTTYPE, ODOTTYPE2: - p.op(ODOTTYPE) - p.pos(n.Pos) - p.expr(n.Left) - p.typ(n.Type) - - case OINDEX, OINDEXMAP: - p.op(OINDEX) - p.pos(n.Pos) - p.expr(n.Left) - p.expr(n.Right) - - case OSLICE, OSLICESTR, OSLICEARR: - p.op(OSLICE) - p.pos(n.Pos) - p.expr(n.Left) - low, high, _ := n.SliceBounds() - p.exprsOrNil(low, high) - - case OSLICE3, OSLICE3ARR: - p.op(OSLICE3) - p.pos(n.Pos) - p.expr(n.Left) - low, high, max := n.SliceBounds() - p.exprsOrNil(low, high) - p.expr(max) - - case OCOPY, OCOMPLEX: - // treated like other builtin calls (see e.g., OREAL) - p.op(op) - p.pos(n.Pos) - p.expr(n.Left) - p.expr(n.Right) - p.op(OEND) - - case OCONV, OCONVIFACE, OCONVNOP, OARRAYBYTESTR, OARRAYRUNESTR, OSTRARRAYBYTE, OSTRARRAYRUNE, ORUNESTR: - p.op(OCONV) - p.pos(n.Pos) - p.expr(n.Left) - p.typ(n.Type) - - case OREAL, OIMAG, OAPPEND, OCAP, OCLOSE, ODELETE, OLEN, OMAKE, ONEW, OPANIC, ORECOVER, OPRINT, OPRINTN: - p.op(op) - p.pos(n.Pos) - if n.Left != nil { - p.expr(n.Left) - p.op(OEND) - } else { - p.exprList(n.List) // emits terminating OEND - } - // only append() calls may contain '...' arguments - if op == OAPPEND { - p.bool(n.Isddd()) - } else if n.Isddd() { - Fatalf("exporter: unexpected '...' with %v call", op) - } - - case OCALL, OCALLFUNC, OCALLMETH, OCALLINTER, OGETG: - p.op(OCALL) - p.pos(n.Pos) - p.expr(n.Left) - p.exprList(n.List) - p.bool(n.Isddd()) - - case OMAKEMAP, OMAKECHAN, OMAKESLICE: - p.op(op) // must keep separate from OMAKE for importer - p.pos(n.Pos) - p.typ(n.Type) - switch { - default: - // empty list - p.op(OEND) - case n.List.Len() != 0: // pre-typecheck - p.exprList(n.List) // emits terminating OEND - case n.Right != nil: - p.expr(n.Left) - p.expr(n.Right) - p.op(OEND) - case n.Left != nil && (n.Op == OMAKESLICE || !n.Left.Type.IsUntyped()): - p.expr(n.Left) - p.op(OEND) - } - - // unary expressions - case OPLUS, OMINUS, OADDR, OCOM, OIND, ONOT, ORECV: - p.op(op) - p.pos(n.Pos) - p.expr(n.Left) - - // binary expressions - case OADD, OAND, OANDAND, OANDNOT, ODIV, OEQ, OGE, OGT, OLE, OLT, - OLSH, OMOD, OMUL, ONE, OOR, OOROR, ORSH, OSEND, OSUB, OXOR: - p.op(op) - p.pos(n.Pos) - p.expr(n.Left) - p.expr(n.Right) - - case OADDSTR: - p.op(OADDSTR) - p.pos(n.Pos) - p.exprList(n.List) - - case OCMPSTR, OCMPIFACE: - p.op(n.SubOp()) - p.pos(n.Pos) - p.expr(n.Left) - p.expr(n.Right) - - case ODCLCONST: - // if exporting, DCLCONST should just be removed as its usage - // has already been replaced with literals - // TODO(gri) these should not be exported in the first place - // TODO(gri) why is this considered an expression in fmt.go? - p.op(ODCLCONST) - p.pos(n.Pos) - - default: - Fatalf("cannot export %v (%d) node\n"+ - "==> please file an issue and assign to gri@\n", n.Op, int(n.Op)) - } -} - -// Caution: stmt will emit more than one node for statement nodes n that have a non-empty -// n.Ninit and where n cannot have a natural init section (such as in "if", "for", etc.). -func (p *exporter) stmt(n *Node) { - if p.trace { - p.tracef("( ") - defer p.tracef(") ") - } - - if n.Ninit.Len() > 0 && !stmtwithinit(n.Op) { - if p.trace { - p.tracef("( /* Ninits */ ") - } - - // can't use stmtList here since we don't want the final OEND - for _, n := range n.Ninit.Slice() { - p.stmt(n) - } - - if p.trace { - p.tracef(") ") - } - } - - switch op := n.Op; op { - case ODCL: - p.op(ODCL) - p.pos(n.Left.Pos) // use declared variable's pos - p.sym(n.Left) - p.typ(n.Left.Type) - - // case ODCLFIELD: - // unimplemented - handled by default case - - case OAS: - // Don't export "v = <N>" initializing statements, hope they're always - // preceded by the DCL which will be re-parsed and typecheck to reproduce - // the "v = <N>" again. - if n.Right != nil { - p.op(OAS) - p.pos(n.Pos) - p.expr(n.Left) - p.expr(n.Right) - } - - case OASOP: - p.op(OASOP) - p.pos(n.Pos) - p.op(n.SubOp()) - p.expr(n.Left) - if p.bool(!n.Implicit()) { - p.expr(n.Right) - } - - case OAS2, OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV: - p.op(OAS2) - p.pos(n.Pos) - p.exprList(n.List) - p.exprList(n.Rlist) - - case ORETURN: - p.op(ORETURN) - p.pos(n.Pos) - p.exprList(n.List) - - // case ORETJMP: - // unreachable - generated by compiler for trampolin routines - - case OPROC, ODEFER: - p.op(op) - p.pos(n.Pos) - p.expr(n.Left) - - case OIF: - p.op(OIF) - p.pos(n.Pos) - p.stmtList(n.Ninit) - p.expr(n.Left) - p.stmtList(n.Nbody) - p.stmtList(n.Rlist) - - case OFOR: - p.op(OFOR) - p.pos(n.Pos) - p.stmtList(n.Ninit) - p.exprsOrNil(n.Left, n.Right) - p.stmtList(n.Nbody) - - case ORANGE: - p.op(ORANGE) - p.pos(n.Pos) - p.stmtList(n.List) - p.expr(n.Right) - p.stmtList(n.Nbody) - - case OSELECT, OSWITCH: - p.op(op) - p.pos(n.Pos) - p.stmtList(n.Ninit) - p.exprsOrNil(n.Left, nil) - p.stmtList(n.List) - - case OCASE, OXCASE: - p.op(OXCASE) - p.pos(n.Pos) - p.stmtList(n.List) - p.stmtList(n.Nbody) - - case OFALL: - p.op(OFALL) - p.pos(n.Pos) - - case OBREAK, OCONTINUE: - p.op(op) - p.pos(n.Pos) - p.exprsOrNil(n.Left, nil) - - case OEMPTY: - // nothing to emit - - case OGOTO, OLABEL: - p.op(op) - p.pos(n.Pos) - p.expr(n.Left) - - default: - Fatalf("exporter: CANNOT EXPORT: %v\nPlease notify gri@\n", n.Op) - } -} - -func (p *exporter) exprsOrNil(a, b *Node) { - ab := 0 - if a != nil { - ab |= 1 - } - if b != nil { - ab |= 2 - } - p.int(ab) - if ab&1 != 0 { - p.expr(a) - } - if ab&2 != 0 { - p.node(b) - } -} - -func (p *exporter) fieldSym(s *types.Sym, short bool) { - name := s.Name - - // remove leading "type." in method names ("(T).m" -> "m") - if short { - if i := strings.LastIndex(name, "."); i >= 0 { - name = name[i+1:] - } - } - - // we should never see a _ (blank) here - these are accessible ("read") fields - // TODO(gri) can we assert this with an explicit check? - p.string(name) - if !types.IsExported(name) { - p.pkg(s.Pkg) - } -} - -// sym must encode the _ (blank) identifier as a single string "_" since -// encoding for some nodes is based on this assumption (e.g. ONAME nodes). -func (p *exporter) sym(n *Node) { - s := n.Sym - if s.Pkg != nil { - if len(s.Name) > 0 && s.Name[0] == '.' { - Fatalf("exporter: exporting synthetic symbol %s", s.Name) - } - } - - if p.trace { - p.tracef("{ SYM ") - defer p.tracef("} ") - } - - name := s.Name - - // remove leading "type." in method names ("(T).m" -> "m") - if i := strings.LastIndex(name, "."); i >= 0 { - name = name[i+1:] - } - - if strings.Contains(name, "·") && n.Name.Vargen > 0 { - Fatalf("exporter: unexpected · in symbol name") - } - - if i := n.Name.Vargen; i > 0 { - name = fmt.Sprintf("%s·%d", name, i) - } - - p.string(name) - if name != "_" { - p.pkg(s.Pkg) - } - // Fixes issue #18167. - p.string(s.Linkname) -} - -func (p *exporter) bool(b bool) bool { - if p.trace { - p.tracef("[") - defer p.tracef("= %v] ", b) - } - - x := 0 - if b { - x = 1 - } - p.int(x) - return b -} - -func (p *exporter) op(op Op) { - if p.trace { - p.tracef("[") - defer p.tracef("= %v] ", op) - } - - p.int(int(op)) -} - -// ---------------------------------------------------------------------------- -// Low-level encoders - -func (p *exporter) index(marker byte, index int) { - if index < 0 { - Fatalf("exporter: invalid index < 0") - } - if debugFormat { - p.marker('t') - } - if p.trace { - p.tracef("%c%d ", marker, index) - } - p.rawInt64(int64(index)) -} - -func (p *exporter) tag(tag int) { - if tag >= 0 { - Fatalf("exporter: invalid tag >= 0") - } - if debugFormat { - p.marker('t') - } - if p.trace { - p.tracef("%s ", tagString[-tag]) - } - p.rawInt64(int64(tag)) -} - -func (p *exporter) int(x int) { - p.int64(int64(x)) -} - -func (p *exporter) int64(x int64) { - if debugFormat { - p.marker('i') - } - if p.trace { - p.tracef("%d ", x) - } - p.rawInt64(x) -} - -func (p *exporter) string(s string) { - if debugFormat { - p.marker('s') - } - if p.trace { - p.tracef("%q ", s) - } - // if we saw the string before, write its index (>= 0) - // (the empty string is mapped to 0) - if i, ok := p.strIndex[s]; ok { - p.rawInt64(int64(i)) - return - } - // otherwise, remember string and write its negative length and bytes - p.strIndex[s] = len(p.strIndex) - p.rawInt64(-int64(len(s))) - for i := 0; i < len(s); i++ { - p.rawByte(s[i]) - } -} - -// marker emits a marker byte and position information which makes -// it easy for a reader to detect if it is "out of sync". Used only -// if debugFormat is set. -func (p *exporter) marker(m byte) { - p.rawByte(m) - // Uncomment this for help tracking down the location - // of an incorrect marker when running in debugFormat. - // if p.trace { - // p.tracef("#%d ", p.written) - // } - p.rawInt64(int64(p.written)) -} - -// rawInt64 should only be used by low-level encoders. -func (p *exporter) rawInt64(x int64) { - var tmp [binary.MaxVarintLen64]byte - n := binary.PutVarint(tmp[:], x) - for i := 0; i < n; i++ { - p.rawByte(tmp[i]) - } -} - -// rawStringln should only be used to emit the initial version string. -func (p *exporter) rawStringln(s string) { - for i := 0; i < len(s); i++ { - p.rawByte(s[i]) - } - p.rawByte('\n') -} - -// rawByte is the bottleneck interface to write to p.out. -// rawByte escapes b as follows (any encoding does that -// hides '$'): -// -// '$' => '|' 'S' -// '|' => '|' '|' -// -// Necessary so other tools can find the end of the -// export data by searching for "$$". -// rawByte should only be used by low-level encoders. -func (p *exporter) rawByte(b byte) { - switch b { - case '$': - // write '$' as '|' 'S' - b = 'S' - fallthrough - case '|': - // write '|' as '|' '|' - p.out.WriteByte('|') - p.written++ - } - p.out.WriteByte(b) - p.written++ -} - -// tracef is like fmt.Printf but it rewrites the format string -// to take care of indentation. -func (p *exporter) tracef(format string, args ...interface{}) { - if strings.ContainsAny(format, "<>\n") { - var buf bytes.Buffer - for i := 0; i < len(format); i++ { - // no need to deal with runes - ch := format[i] - switch ch { - case '>': - p.indent++ - continue - case '<': - p.indent-- - continue - } - buf.WriteByte(ch) - if ch == '\n' { - for j := p.indent; j > 0; j-- { - buf.WriteString(". ") - } - } - } - format = buf.String() - } - fmt.Printf(format, args...) -} - // ---------------------------------------------------------------------------- // Export format @@ -1829,44 +123,6 @@ const ( aliasTag ) -// Debugging support. -// (tagString is only used when tracing is enabled) -var tagString = [...]string{ - // Objects - -packageTag: "package", - -constTag: "const", - -typeTag: "type", - -varTag: "var", - -funcTag: "func", - -endTag: "end", - - // Types - -namedTag: "named type", - -arrayTag: "array", - -sliceTag: "slice", - -dddTag: "ddd", - -structTag: "struct", - -pointerTag: "pointer", - -signatureTag: "signature", - -interfaceTag: "interface", - -mapTag: "map", - -chanTag: "chan", - - // Values - -falseTag: "false", - -trueTag: "true", - -int64Tag: "int64", - -floatTag: "float", - -fractionTag: "fraction", - -complexTag: "complex", - -stringTag: "string", - -nilTag: "nil", - -unknownTag: "unknown", - - // Type aliases - -aliasTag: "alias", -} - // untype returns the "pseudo" untyped type for a Ctype (import/export use only). // (we can't use an pre-initialized array because we must be sure all types are // set up) diff --git a/src/cmd/compile/internal/gc/bimport.go b/src/cmd/compile/internal/gc/bimport.go index c19f548e18..7aabae764e 100644 --- a/src/cmd/compile/internal/gc/bimport.go +++ b/src/cmd/compile/internal/gc/bimport.go @@ -2,340 +2,19 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// Binary package import. -// See bexport.go for the export data format and how -// to make a format change. - package gc import ( - "bufio" "cmd/compile/internal/types" "cmd/internal/src" - "encoding/binary" - "fmt" - "math/big" - "strconv" - "strings" ) -// The overall structure of Import is symmetric to Export: For each -// export method in bexport.go there is a matching and symmetric method -// in bimport.go. Changing the export format requires making symmetric -// changes to bimport.go and bexport.go. - -type importer struct { - in *bufio.Reader - imp *types.Pkg // imported package - buf []byte // reused for reading strings - version int // export format version - - // object lists, in order of deserialization - strList []string - pathList []string - pkgList []*types.Pkg - typList []*types.Type - funcList []*Node // nil entry means already declared - trackAllTypes bool - - // for delayed type verification - cmpList []struct{ pt, t *types.Type } - - // position encoding - posInfoFormat bool - prevFile string - prevLine int - posBase *src.PosBase - - // debugging support - debugFormat bool - read int // bytes read -} - -// Import populates imp from the serialized package data read from in. -func Import(imp *types.Pkg, in *bufio.Reader) { - inimport = true - defer func() { inimport = false }() - - p := importer{ - in: in, - imp: imp, - version: -1, // unknown version - strList: []string{""}, // empty string is mapped to 0 - pathList: []string{""}, // empty path is mapped to 0 - } - - // read version info - var versionstr string - if b := p.rawByte(); b == 'c' || b == 'd' { - // Go1.7 encoding; first byte encodes low-level - // encoding format (compact vs debug). - // For backward-compatibility only (avoid problems with - // old installed packages). Newly compiled packages use - // the extensible format string. - // TODO(gri) Remove this support eventually; after Go1.8. - if b == 'd' { - p.debugFormat = true - } - p.trackAllTypes = p.rawByte() == 'a' - p.posInfoFormat = p.bool() - versionstr = p.string() - if versionstr == "v1" { - p.version = 0 - } - } else { - // Go1.8 extensible encoding - // read version string and extract version number (ignore anything after the version number) - versionstr = p.rawStringln(b) - if s := strings.SplitN(versionstr, " ", 3); len(s) >= 2 && s[0] == "version" { - if v, err := strconv.Atoi(s[1]); err == nil && v > 0 { - p.version = v - } - } - } - - // read version specific flags - extend as necessary - switch p.version { - // case 7: - // ... - // fallthrough - case 6, 5, 4, 3, 2, 1: - p.debugFormat = p.rawStringln(p.rawByte()) == "debug" - p.trackAllTypes = p.bool() - p.posInfoFormat = p.bool() - case 0: - // Go1.7 encoding format - nothing to do here - default: - p.formatErrorf("unknown export format version %d (%q)", p.version, versionstr) - } - - // --- generic export data --- - - // populate typList with predeclared "known" types - p.typList = append(p.typList, predeclared()...) - - // read package data - p.pkg() - - // defer some type-checking until all types are read in completely - tcok := typecheckok - typecheckok = true - defercheckwidth() - - // read objects - - // phase 1 - objcount := 0 - for { - tag := p.tagOrIndex() - if tag == endTag { - break - } - p.obj(tag) - objcount++ - } - - // self-verification - if count := p.int(); count != objcount { - p.formatErrorf("got %d objects; want %d", objcount, count) - } - - // --- compiler-specific export data --- - - // read compiler-specific flags - - // phase 2 - objcount = 0 - for { - tag := p.tagOrIndex() - if tag == endTag { - break - } - p.obj(tag) - objcount++ - } - - // self-verification - if count := p.int(); count != objcount { - p.formatErrorf("got %d objects; want %d", objcount, count) - } - - // read inlineable functions bodies - if dclcontext != PEXTERN { - p.formatErrorf("unexpected context %d", dclcontext) - } - - objcount = 0 - for i0 := -1; ; { - i := p.int() // index of function with inlineable body - if i < 0 { - break - } - - // don't process the same function twice - if i <= i0 { - p.formatErrorf("index not increasing: %d <= %d", i, i0) - } - i0 = i - - if Curfn != nil { - p.formatErrorf("unexpected Curfn %v", Curfn) - } - - // Note: In the original code, funchdr and funcbody are called for - // all functions (that were not yet imported). Now, we are calling - // them only for functions with inlineable bodies. funchdr does - // parameter renaming which doesn't matter if we don't have a body. - - inlCost := p.int() - if f := p.funcList[i]; f != nil && f.Func.Inl == nil { - // function not yet imported - read body and set it - funchdr(f) - body := p.stmtList() - funcbody() - f.Func.Inl = &Inline{ - Cost: int32(inlCost), - Body: body, - } - importlist = append(importlist, f) - if Debug['E'] > 0 && Debug['m'] > 2 { - if Debug['m'] > 3 { - fmt.Printf("inl body for %v: %+v\n", f, asNodes(body)) - } else { - fmt.Printf("inl body for %v: %v\n", f, asNodes(body)) - } - } - } else { - // function already imported - read body but discard declarations - dclcontext = PDISCARD // throw away any declarations - p.stmtList() - dclcontext = PEXTERN - } - - objcount++ - } - - // self-verification - if count := p.int(); count != objcount { - p.formatErrorf("got %d functions; want %d", objcount, count) - } - - if dclcontext != PEXTERN { - p.formatErrorf("unexpected context %d", dclcontext) - } - - p.verifyTypes() - - // --- end of export data --- - - typecheckok = tcok - resumecheckwidth() - - if debug_dclstack != 0 { - testdclstack() - } -} - -func (p *importer) formatErrorf(format string, args ...interface{}) { - if debugFormat { - Fatalf(format, args...) - } - - yyerror("cannot import %q due to version skew - reinstall package (%s)", - p.imp.Path, fmt.Sprintf(format, args...)) - errorexit() -} - -func (p *importer) verifyTypes() { - for _, pair := range p.cmpList { - pt := pair.pt - t := pair.t - if !eqtype(pt.Orig, t) { - p.formatErrorf("inconsistent definition for type %v during import\n\t%L (in %q)\n\t%L (in %q)", pt.Sym, pt, pt.Sym.Importdef.Path, t, p.imp.Path) - } - } -} - // numImport tracks how often a package with a given name is imported. // It is used to provide a better error message (by using the package // path to disambiguate) if a package that appears multiple times with // the same name appears in an error message. var numImport = make(map[string]int) -func (p *importer) pkg() *types.Pkg { - // if the package was seen before, i is its index (>= 0) - i := p.tagOrIndex() - if i >= 0 { - return p.pkgList[i] - } - - // otherwise, i is the package tag (< 0) - if i != packageTag { - p.formatErrorf("expected package tag, found tag = %d", i) - } - - // read package data - name := p.string() - var path string - if p.version >= 5 { - path = p.path() - } else { - path = p.string() - } - var height int - if p.version >= 6 { - height = p.int() - } - - // we should never see an empty package name - if name == "" { - p.formatErrorf("empty package name for path %q", path) - } - - // we should never see a bad import path - if isbadimport(path, true) { - p.formatErrorf("bad package path %q for package %s", path, name) - } - - // an empty path denotes the package we are currently importing; - // it must be the first package we see - if (path == "") != (len(p.pkgList) == 0) { - p.formatErrorf("package path %q for pkg index %d", path, len(p.pkgList)) - } - - if p.version >= 6 { - if height < 0 || height >= types.MaxPkgHeight { - p.formatErrorf("bad package height %v for package %s", height, name) - } - - // reexported packages should always have a lower height than - // the main package - if len(p.pkgList) != 0 && height >= p.imp.Height { - p.formatErrorf("package %q (height %d) reexports package %q (height %d)", p.imp.Path, p.imp.Height, path, height) - } - } - - // add package to pkgList - pkg := p.imp - if path != "" { - pkg = types.NewPkg(path, "") - } - if pkg.Name == "" { - pkg.Name = name - numImport[name]++ - } else if pkg.Name != name { - yyerror("conflicting package names %s and %s for path %q", pkg.Name, name, path) - } - if myimportpath != "" && path == myimportpath { - yyerror("import %q: package depends on %q (import cycle)", p.imp.Path, path) - errorexit() - } - pkg.Height = height - p.pkgList = append(p.pkgList, pkg) - - return pkg -} - func idealType(typ *types.Type) *types.Type { switch typ { case types.Idealint, types.Idealrune, types.Idealfloat, types.Idealcomplex: @@ -345,1013 +24,11 @@ func idealType(typ *types.Type) *types.Type { return typ } -func (p *importer) obj(tag int) { - switch tag { - case constTag: - pos := p.pos() - sym := p.qualifiedName() - typ := p.typ() - val := p.value(typ) - importconst(p.imp, pos, sym, idealType(typ), val) - - case aliasTag: - pos := p.pos() - sym := p.qualifiedName() - typ := p.typ() - importalias(p.imp, pos, sym, typ) - - case typeTag: - p.typ() - - case varTag: - pos := p.pos() - sym := p.qualifiedName() - typ := p.typ() - importvar(p.imp, pos, sym, typ) - - case funcTag: - pos := p.pos() - sym := p.qualifiedName() - params := p.paramList() - result := p.paramList() - - sig := functypefield(nil, params, result) - importfunc(p.imp, pos, sym, sig) - p.funcList = append(p.funcList, asNode(sym.Def)) - - default: - p.formatErrorf("unexpected object (tag = %d)", tag) - } -} - -func (p *importer) pos() src.XPos { - if !p.posInfoFormat { - return src.NoXPos - } - - file := p.prevFile - line := p.prevLine - delta := p.int() - line += delta - if p.version >= 5 { - if delta == deltaNewFile { - if n := p.int(); n >= 0 { - // file changed - file = p.path() - line = n - } - } - } else { - if delta == 0 { - if n := p.int(); n >= 0 { - // file changed - file = p.prevFile[:n] + p.string() - line = p.int() - } - } - } - if file != p.prevFile { - p.prevFile = file - p.posBase = src.NewFileBase(file, file) - } - p.prevLine = line - - pos := src.MakePos(p.posBase, uint(line), 0) - xpos := Ctxt.PosTable.XPos(pos) - return xpos -} - -func (p *importer) path() string { - // if the path was seen before, i is its index (>= 0) - // (the empty string is at index 0) - i := p.int() - if i >= 0 { - return p.pathList[i] - } - // otherwise, i is the negative path length (< 0) - a := make([]string, -i) - for n := range a { - a[n] = p.string() - } - s := strings.Join(a, "/") - p.pathList = append(p.pathList, s) - return s -} - -func (p *importer) newtyp(etype types.EType) *types.Type { - t := types.New(etype) - if p.trackAllTypes { - p.typList = append(p.typList, t) - } - return t -} - -// importtype declares that pt, an imported named type, has underlying type t. -func (p *importer) importtype(pt, t *types.Type) { - if pt.Etype == TFORW { - copytype(typenod(pt), t) - checkwidth(pt) - } else { - // pt.Orig and t must be identical. - if p.trackAllTypes { - // If we track all types, t may not be fully set up yet. - // Collect the types and verify identity later. - p.cmpList = append(p.cmpList, struct{ pt, t *types.Type }{pt, t}) - } else if !eqtype(pt.Orig, t) { - yyerror("inconsistent definition for type %v during import\n\t%L (in %q)\n\t%L (in %q)", pt.Sym, pt, pt.Sym.Importdef.Path, t, p.imp.Path) - } - } - - if Debug['E'] != 0 { - fmt.Printf("import type %v %L\n", pt, t) - } -} - -func (p *importer) typ() *types.Type { - // if the type was seen before, i is its index (>= 0) - i := p.tagOrIndex() - if i >= 0 { - return p.typList[i] - } - - // otherwise, i is the type tag (< 0) - var t *types.Type - switch i { - case namedTag: - pos := p.pos() - tsym := p.qualifiedName() - - t = importtype(p.imp, pos, tsym) - p.typList = append(p.typList, t) - dup := !t.IsKind(types.TFORW) // type already imported - - // read underlying type - t0 := p.typ() - p.importtype(t, t0) - - // interfaces don't have associated methods - if t0.IsInterface() { - break - } - - // set correct import context (since p.typ() may be called - // while importing the body of an inlined function) - savedContext := dclcontext - dclcontext = PEXTERN - - // read associated methods - for i := p.int(); i > 0; i-- { - mpos := p.pos() - sym := p.fieldSym() - - // during import unexported method names should be in the type's package - if !types.IsExported(sym.Name) && sym.Pkg != tsym.Pkg { - Fatalf("imported method name %+v in wrong package %s\n", sym, tsym.Pkg.Name) - } - - recv := p.paramList() // TODO(gri) do we need a full param list for the receiver? - params := p.paramList() - result := p.paramList() - nointerface := p.bool() - - mt := functypefield(recv[0], params, result) - oldm := addmethod(sym, mt, false, nointerface) - - if dup { - // An earlier import already declared this type and its methods. - // Discard the duplicate method declaration. - n := asNode(oldm.Type.Nname()) - p.funcList = append(p.funcList, n) - continue - } - - n := newfuncnamel(mpos, methodSym(recv[0].Type, sym)) - n.Type = mt - n.SetClass(PFUNC) - checkwidth(n.Type) - p.funcList = append(p.funcList, n) - - // (comment from parser.go) - // inl.C's inlnode in on a dotmeth node expects to find the inlineable body as - // (dotmeth's type).Nname.Inl, and dotmeth's type has been pulled - // out by typecheck's lookdot as this $$.ttype. So by providing - // this back link here we avoid special casing there. - mt.SetNname(asTypesNode(n)) - - if Debug['E'] > 0 { - fmt.Printf("import [%q] meth %v \n", p.imp.Path, n) - } - } - - dclcontext = savedContext - - case arrayTag: - t = p.newtyp(TARRAY) - bound := p.int64() - elem := p.typ() - t.Extra = &types.Array{Elem: elem, Bound: bound} - - case sliceTag: - t = p.newtyp(TSLICE) - elem := p.typ() - t.Extra = types.Slice{Elem: elem} - - case dddTag: - t = p.newtyp(TDDDFIELD) - t.Extra = types.DDDField{T: p.typ()} - - case structTag: - t = p.newtyp(TSTRUCT) - t.SetFields(p.fieldList()) - checkwidth(t) - - case pointerTag: - t = p.newtyp(types.Tptr) - t.Extra = types.Ptr{Elem: p.typ()} - - case signatureTag: - t = p.newtyp(TFUNC) - params := p.paramList() - result := p.paramList() - functypefield0(t, nil, params, result) - - case interfaceTag: - if ml := p.methodList(); len(ml) == 0 { - t = types.Types[TINTER] - } else { - t = p.newtyp(TINTER) - t.SetInterface(ml) - } - - case mapTag: - t = p.newtyp(TMAP) - mt := t.MapType() - mt.Key = p.typ() - mt.Elem = p.typ() - - case chanTag: - t = p.newtyp(TCHAN) - ct := t.ChanType() - ct.Dir = types.ChanDir(p.int()) - ct.Elem = p.typ() - - default: - p.formatErrorf("unexpected type (tag = %d)", i) - } - - if t == nil { - p.formatErrorf("nil type (type tag = %d)", i) - } - - return t -} - -func (p *importer) qualifiedName() *types.Sym { - name := p.string() - pkg := p.pkg() - return pkg.Lookup(name) -} - -func (p *importer) fieldList() (fields []*types.Field) { - if n := p.int(); n > 0 { - fields = make([]*types.Field, n) - for i := range fields { - fields[i] = p.field() - } - } - return -} - -func (p *importer) field() *types.Field { - pos := p.pos() - sym, alias := p.fieldName() - typ := p.typ() - note := p.string() - - f := types.NewField() - if sym.Name == "" { - // anonymous field: typ must be T or *T and T must be a type name - s := typ.Sym - if s == nil && typ.IsPtr() { - s = typ.Elem().Sym // deref - } - sym = sym.Pkg.Lookup(s.Name) - f.Embedded = 1 - } else if alias { - // anonymous field: we have an explicit name because it's a type alias - f.Embedded = 1 - } - - f.Pos = pos - f.Sym = sym - f.Type = typ - f.Note = note - - return f -} - -func (p *importer) methodList() (methods []*types.Field) { - for n := p.int(); n > 0; n-- { - f := types.NewField() - f.Pos = p.pos() - f.Type = p.typ() - methods = append(methods, f) - } - - for n := p.int(); n > 0; n-- { - methods = append(methods, p.method()) - } - - return -} - -func (p *importer) method() *types.Field { - pos := p.pos() - sym := p.methodName() - params := p.paramList() - result := p.paramList() - - f := types.NewField() - f.Pos = pos - f.Sym = sym - f.Type = functypefield(fakeRecvField(), params, result) - return f -} - -func (p *importer) fieldName() (*types.Sym, bool) { - name := p.string() - if p.version == 0 && name == "_" { - // version 0 didn't export a package for _ field names - // but used the builtin package instead - return builtinpkg.Lookup(name), false - } - pkg := localpkg - alias := false - switch name { - case "": - // 1) field name matches base type name and is exported: nothing to do - case "?": - // 2) field name matches base type name and is not exported: need package - name = "" - pkg = p.pkg() - case "@": - // 3) field name doesn't match base type name (alias name): need name and possibly package - name = p.string() - alias = true - fallthrough - default: - if !types.IsExported(name) { - pkg = p.pkg() - } - } - return pkg.Lookup(name), alias -} - -func (p *importer) methodName() *types.Sym { - name := p.string() - if p.version == 0 && name == "_" { - // version 0 didn't export a package for _ method names - // but used the builtin package instead - return builtinpkg.Lookup(name) - } - pkg := localpkg - if !types.IsExported(name) { - pkg = p.pkg() - } - return pkg.Lookup(name) -} - -func (p *importer) paramList() []*types.Field { - i := p.int() - if i == 0 { - return nil - } - // negative length indicates unnamed parameters - named := true - if i < 0 { - i = -i - named = false - } - // i > 0 - fs := make([]*types.Field, i) - for i := range fs { - fs[i] = p.param(named) - } - return fs -} - -func (p *importer) param(named bool) *types.Field { - f := types.NewField() - // TODO(mdempsky): Need param position. - f.Pos = lineno - f.Type = p.typ() - if f.Type.Etype == TDDDFIELD { - // TDDDFIELD indicates wrapped ... slice type - f.Type = types.NewSlice(f.Type.DDDField()) - f.SetIsddd(true) - } - - if named { - name := p.string() - if name == "" { - p.formatErrorf("expected named parameter") - } - // TODO(gri) Supply function/method package rather than - // encoding the package for each parameter repeatedly. - pkg := localpkg - if name != "_" { - pkg = p.pkg() - } - f.Sym = pkg.Lookup(name) - } - - // TODO(gri) This is compiler-specific (escape info). - // Move into compiler-specific section eventually? - f.Note = p.string() - - return f -} - -func (p *importer) value(typ *types.Type) (x Val) { - switch tag := p.tagOrIndex(); tag { - case falseTag: - x.U = false - - case trueTag: - x.U = true - - case int64Tag: - u := new(Mpint) - u.SetInt64(p.int64()) - u.Rune = typ == types.Idealrune - x.U = u - - case floatTag: - f := newMpflt() - p.float(f) - if typ == types.Idealint || typ.IsInteger() || typ.IsPtr() || typ.IsUnsafePtr() { - // uncommon case: large int encoded as float - // - // This happens for unsigned typed integers - // and (on 64-bit platforms) pointers because - // of values in the range [2^63, 2^64). - u := new(Mpint) - u.SetFloat(f) - x.U = u - break - } - x.U = f - - case complexTag: - u := new(Mpcplx) - p.float(&u.Real) - p.float(&u.Imag) - x.U = u - - case stringTag: - x.U = p.string() - - case unknownTag: - p.formatErrorf("unknown constant (importing package with errors)") - - case nilTag: - x.U = new(NilVal) - - default: - p.formatErrorf("unexpected value tag %d", tag) - } - - // verify ideal type - if typ.IsUntyped() && untype(x.Ctype()) != typ { - p.formatErrorf("value %v and type %v don't match", x, typ) - } - - return -} - -func (p *importer) float(x *Mpflt) { - sign := p.int() - if sign == 0 { - x.SetFloat64(0) - return - } - - exp := p.int() - mant := new(big.Int).SetBytes([]byte(p.string())) - - m := x.Val.SetInt(mant) - m.SetMantExp(m, exp-mant.BitLen()) - if sign < 0 { - m.Neg(m) - } -} - -// ---------------------------------------------------------------------------- -// Inlined function bodies - -// Approach: Read nodes and use them to create/declare the same data structures -// as done originally by the (hidden) parser by closely following the parser's -// original code. In other words, "parsing" the import data (which happens to -// be encoded in binary rather textual form) is the best way at the moment to -// re-establish the syntax tree's invariants. At some future point we might be -// able to avoid this round-about way and create the rewritten nodes directly, -// possibly avoiding a lot of duplicate work (name resolution, type checking). -// -// Refined nodes (e.g., ODOTPTR as a refinement of OXDOT) are exported as their -// unrefined nodes (since this is what the importer uses). The respective case -// entries are unreachable in the importer. - -func (p *importer) stmtList() []*Node { - var list []*Node - for { - n := p.node() - if n == nil { - break - } - // OBLOCK nodes may be created when importing ODCL nodes - unpack them - if n.Op == OBLOCK { - list = append(list, n.List.Slice()...) - } else { - list = append(list, n) - } - } - return list -} - -func (p *importer) exprList() []*Node { - var list []*Node - for { - n := p.expr() - if n == nil { - break - } - list = append(list, n) - } - return list -} - -func (p *importer) elemList() []*Node { - c := p.int() - list := make([]*Node, c) - for i := range list { - s := p.fieldSym() - list[i] = nodSym(OSTRUCTKEY, p.expr(), s) - } - return list -} - -func (p *importer) expr() *Node { - n := p.node() - if n != nil && n.Op == OBLOCK { - Fatalf("unexpected block node: %v", n) - } - return n -} - func npos(pos src.XPos, n *Node) *Node { n.Pos = pos return n } -// TODO(gri) split into expr and stmt -func (p *importer) node() *Node { - switch op := p.op(); op { - // expressions - // case OPAREN: - // unreachable - unpacked by exporter - - // case ODDDARG: - // unimplemented - - case OLITERAL: - pos := p.pos() - typ := p.typ() - n := npos(pos, nodlit(p.value(typ))) - n.Type = idealType(typ) - return n - - case ONAME: - return npos(p.pos(), mkname(p.sym())) - - // case OPACK, ONONAME: - // unreachable - should have been resolved by typechecking - - case OTYPE: - return npos(p.pos(), typenod(p.typ())) - - // case OTARRAY, OTMAP, OTCHAN, OTSTRUCT, OTINTER, OTFUNC: - // unreachable - should have been resolved by typechecking - - // case OCLOSURE: - // unimplemented - - case OPTRLIT: - pos := p.pos() - n := npos(pos, p.expr()) - if !p.bool() /* !implicit, i.e. '&' operator */ { - if n.Op == OCOMPLIT { - // Special case for &T{...}: turn into (*T){...}. - n.Right = nodl(pos, OIND, n.Right, nil) - n.Right.SetImplicit(true) - } else { - n = nodl(pos, OADDR, n, nil) - } - } - return n - - case OSTRUCTLIT: - // TODO(mdempsky): Export position information for OSTRUCTKEY nodes. - savedlineno := lineno - lineno = p.pos() - n := nodl(lineno, OCOMPLIT, nil, typenod(p.typ())) - n.List.Set(p.elemList()) // special handling of field names - lineno = savedlineno - return n - - // case OARRAYLIT, OSLICELIT, OMAPLIT: - // unreachable - mapped to case OCOMPLIT below by exporter - - case OCOMPLIT: - n := nodl(p.pos(), OCOMPLIT, nil, typenod(p.typ())) - n.List.Set(p.exprList()) - return n - - case OKEY: - pos := p.pos() - left, right := p.exprsOrNil() - return nodl(pos, OKEY, left, right) - - // case OSTRUCTKEY: - // unreachable - handled in case OSTRUCTLIT by elemList - - // case OCALLPART: - // unimplemented - - // case OXDOT, ODOT, ODOTPTR, ODOTINTER, ODOTMETH: - // unreachable - mapped to case OXDOT below by exporter - - case OXDOT: - // see parser.new_dotname - return npos(p.pos(), nodSym(OXDOT, p.expr(), p.fieldSym())) - - // case ODOTTYPE, ODOTTYPE2: - // unreachable - mapped to case ODOTTYPE below by exporter - - case ODOTTYPE: - n := nodl(p.pos(), ODOTTYPE, p.expr(), nil) - n.Type = p.typ() - return n - - // case OINDEX, OINDEXMAP, OSLICE, OSLICESTR, OSLICEARR, OSLICE3, OSLICE3ARR: - // unreachable - mapped to cases below by exporter - - case OINDEX: - return nodl(p.pos(), op, p.expr(), p.expr()) - - case OSLICE, OSLICE3: - n := nodl(p.pos(), op, p.expr(), nil) - low, high := p.exprsOrNil() - var max *Node - if n.Op.IsSlice3() { - max = p.expr() - } - n.SetSliceBounds(low, high, max) - return n - - // case OCONV, OCONVIFACE, OCONVNOP, OARRAYBYTESTR, OARRAYRUNESTR, OSTRARRAYBYTE, OSTRARRAYRUNE, ORUNESTR: - // unreachable - mapped to OCONV case below by exporter - - case OCONV: - n := nodl(p.pos(), OCONV, p.expr(), nil) - n.Type = p.typ() - return n - - case OCOPY, OCOMPLEX, OREAL, OIMAG, OAPPEND, OCAP, OCLOSE, ODELETE, OLEN, OMAKE, ONEW, OPANIC, ORECOVER, OPRINT, OPRINTN: - n := npos(p.pos(), builtinCall(op)) - n.List.Set(p.exprList()) - if op == OAPPEND { - n.SetIsddd(p.bool()) - } - return n - - // case OCALL, OCALLFUNC, OCALLMETH, OCALLINTER, OGETG: - // unreachable - mapped to OCALL case below by exporter - - case OCALL: - n := nodl(p.pos(), OCALL, p.expr(), nil) - n.List.Set(p.exprList()) - n.SetIsddd(p.bool()) - return n - - case OMAKEMAP, OMAKECHAN, OMAKESLICE: - n := npos(p.pos(), builtinCall(OMAKE)) - n.List.Append(typenod(p.typ())) - n.List.Append(p.exprList()...) - return n - - // unary expressions - case OPLUS, OMINUS, OADDR, OCOM, OIND, ONOT, ORECV: - return nodl(p.pos(), op, p.expr(), nil) - - // binary expressions - case OADD, OAND, OANDAND, OANDNOT, ODIV, OEQ, OGE, OGT, OLE, OLT, - OLSH, OMOD, OMUL, ONE, OOR, OOROR, ORSH, OSEND, OSUB, OXOR: - return nodl(p.pos(), op, p.expr(), p.expr()) - - case OADDSTR: - pos := p.pos() - list := p.exprList() - x := npos(pos, list[0]) - for _, y := range list[1:] { - x = nodl(pos, OADD, x, y) - } - return x - - // case OCMPSTR, OCMPIFACE: - // unreachable - mapped to std comparison operators by exporter - - case ODCLCONST: - // TODO(gri) these should not be exported in the first place - return nodl(p.pos(), OEMPTY, nil, nil) - - // -------------------------------------------------------------------- - // statements - case ODCL: - if p.version < 2 { - // versions 0 and 1 exported a bool here but it - // was always false - simply ignore in this case - p.bool() - } - pos := p.pos() - lhs := npos(pos, dclname(p.sym())) - typ := typenod(p.typ()) - return npos(pos, liststmt(variter([]*Node{lhs}, typ, nil))) // TODO(gri) avoid list creation - - // case ODCLFIELD: - // unimplemented - - // case OAS, OASWB: - // unreachable - mapped to OAS case below by exporter - - case OAS: - return nodl(p.pos(), OAS, p.expr(), p.expr()) - - case OASOP: - n := nodl(p.pos(), OASOP, nil, nil) - n.SetSubOp(p.op()) - n.Left = p.expr() - if !p.bool() { - n.Right = nodintconst(1) - n.SetImplicit(true) - } else { - n.Right = p.expr() - } - return n - - // case OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV: - // unreachable - mapped to OAS2 case below by exporter - - case OAS2: - n := nodl(p.pos(), OAS2, nil, nil) - n.List.Set(p.exprList()) - n.Rlist.Set(p.exprList()) - return n - - case ORETURN: - n := nodl(p.pos(), ORETURN, nil, nil) - n.List.Set(p.exprList()) - return n - - // case ORETJMP: - // unreachable - generated by compiler for trampolin routines (not exported) - - case OPROC, ODEFER: - return nodl(p.pos(), op, p.expr(), nil) - - case OIF: - n := nodl(p.pos(), OIF, nil, nil) - n.Ninit.Set(p.stmtList()) - n.Left = p.expr() - n.Nbody.Set(p.stmtList()) - n.Rlist.Set(p.stmtList()) - return n - - case OFOR: - n := nodl(p.pos(), OFOR, nil, nil) - n.Ninit.Set(p.stmtList()) - n.Left, n.Right = p.exprsOrNil() - n.Nbody.Set(p.stmtList()) - return n - - case ORANGE: - n := nodl(p.pos(), ORANGE, nil, nil) - n.List.Set(p.stmtList()) - n.Right = p.expr() - n.Nbody.Set(p.stmtList()) - return n - - case OSELECT, OSWITCH: - n := nodl(p.pos(), op, nil, nil) - n.Ninit.Set(p.stmtList()) - n.Left, _ = p.exprsOrNil() - n.List.Set(p.stmtList()) - return n - - // case OCASE, OXCASE: - // unreachable - mapped to OXCASE case below by exporter - - case OXCASE: - n := nodl(p.pos(), OXCASE, nil, nil) - n.List.Set(p.exprList()) - // TODO(gri) eventually we must declare variables for type switch - // statements (type switch statements are not yet exported) - n.Nbody.Set(p.stmtList()) - return n - - // case OFALL: - // unreachable - mapped to OXFALL case below by exporter - - case OFALL: - n := nodl(p.pos(), OFALL, nil, nil) - return n - - case OBREAK, OCONTINUE: - pos := p.pos() - left, _ := p.exprsOrNil() - if left != nil { - left = newname(left.Sym) - } - return nodl(pos, op, left, nil) - - // case OEMPTY: - // unreachable - not emitted by exporter - - case OGOTO, OLABEL: - return nodl(p.pos(), op, newname(p.expr().Sym), nil) - - case OEND: - return nil - - default: - Fatalf("cannot import %v (%d) node\n"+ - "==> please file an issue and assign to gri@\n", op, int(op)) - panic("unreachable") // satisfy compiler - } -} - func builtinCall(op Op) *Node { return nod(OCALL, mkname(builtinpkg.Lookup(goopnames[op])), nil) } - -func (p *importer) exprsOrNil() (a, b *Node) { - ab := p.int() - if ab&1 != 0 { - a = p.expr() - } - if ab&2 != 0 { - b = p.node() - } - return -} - -func (p *importer) fieldSym() *types.Sym { - name := p.string() - pkg := localpkg - if !types.IsExported(name) { - pkg = p.pkg() - } - return pkg.Lookup(name) -} - -func (p *importer) sym() *types.Sym { - name := p.string() - pkg := localpkg - if name != "_" { - pkg = p.pkg() - } - linkname := p.string() - sym := pkg.Lookup(name) - sym.Linkname = linkname - return sym -} - -func (p *importer) bool() bool { - return p.int() != 0 -} - -func (p *importer) op() Op { - return Op(p.int()) -} - -// ---------------------------------------------------------------------------- -// Low-level decoders - -func (p *importer) tagOrIndex() int { - if p.debugFormat { - p.marker('t') - } - - return int(p.rawInt64()) -} - -func (p *importer) int() int { - x := p.int64() - if int64(int(x)) != x { - p.formatErrorf("exported integer too large") - } - return int(x) -} - -func (p *importer) int64() int64 { - if p.debugFormat { - p.marker('i') - } - - return p.rawInt64() -} - -func (p *importer) string() string { - if p.debugFormat { - p.marker('s') - } - // if the string was seen before, i is its index (>= 0) - // (the empty string is at index 0) - i := p.rawInt64() - if i >= 0 { - return p.strList[i] - } - // otherwise, i is the negative string length (< 0) - if n := int(-i); n <= cap(p.buf) { - p.buf = p.buf[:n] - } else { - p.buf = make([]byte, n) - } - for i := range p.buf { - p.buf[i] = p.rawByte() - } - s := string(p.buf) - p.strList = append(p.strList, s) - return s -} - -func (p *importer) marker(want byte) { - if got := p.rawByte(); got != want { - p.formatErrorf("incorrect marker: got %c; want %c (pos = %d)", got, want, p.read) - } - - pos := p.read - if n := int(p.rawInt64()); n != pos { - p.formatErrorf("incorrect position: got %d; want %d", n, pos) - } -} - -// rawInt64 should only be used by low-level decoders. -func (p *importer) rawInt64() int64 { - i, err := binary.ReadVarint(p) - if err != nil { - p.formatErrorf("read error: %v", err) - } - return i -} - -// rawStringln should only be used to read the initial version string. -func (p *importer) rawStringln(b byte) string { - p.buf = p.buf[:0] - for b != '\n' { - p.buf = append(p.buf, b) - b = p.rawByte() - } - return string(p.buf) -} - -// needed for binary.ReadVarint in rawInt64 -func (p *importer) ReadByte() (byte, error) { - return p.rawByte(), nil -} - -// rawByte is the bottleneck interface for reading from p.in. -// It unescapes '|' 'S' to '$' and '|' '|' to '|'. -// rawByte should only be used by low-level decoders. -func (p *importer) rawByte() byte { - c, err := p.in.ReadByte() - p.read++ - if err != nil { - p.formatErrorf("read error: %v", err) - } - if c == '|' { - c, err = p.in.ReadByte() - p.read++ - if err != nil { - p.formatErrorf("read error: %v", err) - } - switch c { - case 'S': - c = '$' - case '|': - // nothing to do - default: - p.formatErrorf("unexpected escape sequence in export data") - } - } - return c -} diff --git a/src/cmd/compile/internal/gc/const.go b/src/cmd/compile/internal/gc/const.go index 1403a2be11..02d51678be 100644 --- a/src/cmd/compile/internal/gc/const.go +++ b/src/cmd/compile/internal/gc/const.go @@ -234,7 +234,7 @@ func convlit1(n *Node, t *types.Type, explicit bool, reuse canReuseNode) *Node { if n.Op == OLITERAL && !reuse { // Can't always set n.Type directly on OLITERAL nodes. // See discussion on CL 20813. - n = n.copy() + n = n.rawcopy() reuse = true } @@ -476,7 +476,7 @@ func toflt(v Val) Val { f := newMpflt() f.Set(&u.Real) if u.Imag.CmpFloat64(0) != 0 { - yyerror("constant %v%vi truncated to real", fconv(&u.Real, FmtSharp), fconv(&u.Imag, FmtSharp|FmtSign)) + yyerror("constant %v truncated to real", u.GoString()) } v.U = f } @@ -509,11 +509,11 @@ func toint(v Val) Val { // value from the error message. // (See issue #11371). var t big.Float - t.Parse(fconv(u, FmtSharp), 10) + t.Parse(u.GoString(), 10) if t.IsInt() { yyerror("constant truncated to integer") } else { - yyerror("constant %v truncated to integer", fconv(u, FmtSharp)) + yyerror("constant %v truncated to integer", u.GoString()) } } } @@ -522,7 +522,7 @@ func toint(v Val) Val { case *Mpcplx: i := new(Mpint) if !i.SetFloat(&u.Real) || u.Imag.CmpFloat64(0) != 0 { - yyerror("constant %v%vi truncated to integer", fconv(&u.Real, FmtSharp), fconv(&u.Imag, FmtSharp|FmtSign)) + yyerror("constant %v truncated to integer", u.GoString()) } v.U = i @@ -1200,8 +1200,7 @@ func setconst(n *Node, v Val) { // Ensure n.Orig still points to a semantically-equivalent // expression after we rewrite n into a constant. if n.Orig == n { - n.Orig = n.copy() - n.Orig.Orig = n.Orig + n.Orig = n.sepcopy() } *n = Node{ @@ -1331,7 +1330,7 @@ func defaultlitreuse(n *Node, t *types.Type, reuse canReuseNode) *Node { } if n.Op == OLITERAL && !reuse { - n = n.copy() + n = n.rawcopy() reuse = true } diff --git a/src/cmd/compile/internal/gc/dump.go b/src/cmd/compile/internal/gc/dump.go new file mode 100644 index 0000000000..8de90adf05 --- /dev/null +++ b/src/cmd/compile/internal/gc/dump.go @@ -0,0 +1,287 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file implements textual dumping of arbitrary data structures +// for debugging purposes. The code is customized for Node graphs +// and may be used for an alternative view of the node structure. + +package gc + +import ( + "cmd/compile/internal/types" + "cmd/internal/src" + "fmt" + "io" + "os" + "reflect" + "regexp" + "unicode" + "unicode/utf8" +) + +// dump is like fdump but prints to stderr. +func dump(root interface{}, filter string, depth int) { + fdump(os.Stderr, root, filter, depth) +} + +// fdump prints the structure of a rooted data structure +// to w by depth-first traversal of the data structure. +// +// The filter parameter is a regular expression. If it is +// non-empty, only struct fields whose names match filter +// are printed. +// +// The depth parameter controls how deep traversal recurses +// before it returns (higher value means greater depth). +// If an empty field filter is given, a good depth default value +// is 4. A negative depth means no depth limit, which may be fine +// for small data structures or if there is a non-empty filter. +// +// In the output, Node structs are identified by their Op name +// rather than their type; struct fields with zero values or +// non-matching field names are omitted, and "…" means recursion +// depth has been reached or struct fields have been omitted. +func fdump(w io.Writer, root interface{}, filter string, depth int) { + if root == nil { + fmt.Fprintln(w, "nil") + return + } + + if filter == "" { + filter = ".*" // default + } + + p := dumper{ + output: w, + fieldrx: regexp.MustCompile(filter), + ptrmap: make(map[uintptr]int), + last: '\n', // force printing of line number on first line + } + + p.dump(reflect.ValueOf(root), depth) + p.printf("\n") +} + +type dumper struct { + output io.Writer + fieldrx *regexp.Regexp // field name filter + ptrmap map[uintptr]int // ptr -> dump line number + lastadr string // last address string printed (for shortening) + + // output + indent int // current indentation level + last byte // last byte processed by Write + line int // current line number +} + +var indentBytes = []byte(". ") + +func (p *dumper) Write(data []byte) (n int, err error) { + var m int + for i, b := range data { + // invariant: data[0:n] has been written + if b == '\n' { + m, err = p.output.Write(data[n : i+1]) + n += m + if err != nil { + return + } + } else if p.last == '\n' { + p.line++ + _, err = fmt.Fprintf(p.output, "%6d ", p.line) + if err != nil { + return + } + for j := p.indent; j > 0; j-- { + _, err = p.output.Write(indentBytes) + if err != nil { + return + } + } + } + p.last = b + } + if len(data) > n { + m, err = p.output.Write(data[n:]) + n += m + } + return +} + +// printf is a convenience wrapper. +func (p *dumper) printf(format string, args ...interface{}) { + if _, err := fmt.Fprintf(p, format, args...); err != nil { + panic(err) + } +} + +// addr returns the (hexadecimal) address string of the object +// represented by x (or "?" if x is not addressable), with the +// common prefix between this and the prior address replaced by +// "0x…" to make it easier to visually match addresses. +func (p *dumper) addr(x reflect.Value) string { + if !x.CanAddr() { + return "?" + } + adr := fmt.Sprintf("%p", x.Addr().Interface()) + s := adr + if i := commonPrefixLen(p.lastadr, adr); i > 0 { + s = "0x…" + adr[i:] + } + p.lastadr = adr + return s +} + +// dump prints the contents of x. +func (p *dumper) dump(x reflect.Value, depth int) { + if depth == 0 { + p.printf("…") + return + } + + // special cases + switch v := x.Interface().(type) { + case Nodes: + // unpack Nodes since reflect cannot look inside + // due to the unexported field in its struct + x = reflect.ValueOf(v.Slice()) + + case src.XPos: + p.printf("%s", linestr(v)) + return + + case *types.Node: + x = reflect.ValueOf(asNode(v)) + } + + switch x.Kind() { + case reflect.String: + p.printf("%q", x.Interface()) // print strings in quotes + + case reflect.Interface: + if x.IsNil() { + p.printf("nil") + return + } + p.dump(x.Elem(), depth-1) + + case reflect.Ptr: + if x.IsNil() { + p.printf("nil") + return + } + + p.printf("*") + ptr := x.Pointer() + if line, exists := p.ptrmap[ptr]; exists { + p.printf("(@%d)", line) + return + } + p.ptrmap[ptr] = p.line + p.dump(x.Elem(), depth) // don't count pointer indirection towards depth + + case reflect.Slice: + if x.IsNil() { + p.printf("nil") + return + } + p.printf("%s (%d entries) {", x.Type(), x.Len()) + if x.Len() > 0 { + p.indent++ + p.printf("\n") + for i, n := 0, x.Len(); i < n; i++ { + p.printf("%d: ", i) + p.dump(x.Index(i), depth-1) + p.printf("\n") + } + p.indent-- + } + p.printf("}") + + case reflect.Struct: + typ := x.Type() + + isNode := false + if n, ok := x.Interface().(Node); ok { + isNode = true + p.printf("%s %s {", n.Op.String(), p.addr(x)) + } else { + p.printf("%s {", typ) + } + p.indent++ + + first := true + omitted := false + for i, n := 0, typ.NumField(); i < n; i++ { + // Exclude non-exported fields because their + // values cannot be accessed via reflection. + if name := typ.Field(i).Name; isExported(name) { + if !p.fieldrx.MatchString(name) { + omitted = true + continue // field name not selected by filter + } + + // special cases + if isNode && name == "Op" { + omitted = true + continue // Op field already printed for Nodes + } + x := x.Field(i) + if isZeroVal(x) { + omitted = true + continue // exclude zero-valued fields + } + if n, ok := x.Interface().(Nodes); ok && n.Len() == 0 { + omitted = true + continue // exclude empty Nodes slices + } + + if first { + p.printf("\n") + first = false + } + p.printf("%s: ", name) + p.dump(x, depth-1) + p.printf("\n") + } + } + if omitted { + p.printf("…\n") + } + + p.indent-- + p.printf("}") + + default: + p.printf("%v", x.Interface()) + } +} + +func isZeroVal(x reflect.Value) bool { + switch x.Kind() { + case reflect.Bool: + return !x.Bool() + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + return x.Int() == 0 + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + return x.Uint() == 0 + case reflect.String: + return x.String() == "" + case reflect.Interface, reflect.Ptr, reflect.Slice: + return x.IsNil() + } + return false +} + +func isExported(name string) bool { + ch, _ := utf8.DecodeRuneInString(name) + return unicode.IsUpper(ch) +} + +func commonPrefixLen(a, b string) (i int) { + for i < len(a) && i < len(b) && a[i] == b[i] { + i++ + } + return +} diff --git a/src/cmd/compile/internal/gc/esc.go b/src/cmd/compile/internal/gc/esc.go index 9db6c8e0b4..145007f5e1 100644 --- a/src/cmd/compile/internal/gc/esc.go +++ b/src/cmd/compile/internal/gc/esc.go @@ -654,9 +654,71 @@ func (e *EscState) esclist(l Nodes, parent *Node) { } } +func (e *EscState) isSliceSelfAssign(dst, src *Node) bool { + // Detect the following special case. + // + // func (b *Buffer) Foo() { + // n, m := ... + // b.buf = b.buf[n:m] + // } + // + // This assignment is a no-op for escape analysis, + // it does not store any new pointers into b that were not already there. + // However, without this special case b will escape, because we assign to OIND/ODOTPTR. + // Here we assume that the statement will not contain calls, + // that is, that order will move any calls to init. + // Otherwise base ONAME value could change between the moments + // when we evaluate it for dst and for src. + + // dst is ONAME dereference. + if dst.Op != OIND && dst.Op != ODOTPTR || dst.Left.Op != ONAME { + return false + } + // src is a slice operation. + switch src.Op { + case OSLICE, OSLICE3, OSLICESTR: + // OK. + case OSLICEARR, OSLICE3ARR: + // Since arrays are embedded into containing object, + // slice of non-pointer array will introduce a new pointer into b that was not already there + // (pointer to b itself). After such assignment, if b contents escape, + // b escapes as well. If we ignore such OSLICEARR, we will conclude + // that b does not escape when b contents do. + // + // Pointer to an array is OK since it's not stored inside b directly. + // For slicing an array (not pointer to array), there is an implicit OADDR. + // We check that to determine non-pointer array slicing. + if src.Left.Op == OADDR { + return false + } + default: + return false + } + // slice is applied to ONAME dereference. + if src.Left.Op != OIND && src.Left.Op != ODOTPTR || src.Left.Left.Op != ONAME { + return false + } + // dst and src reference the same base ONAME. + return dst.Left == src.Left.Left +} + // isSelfAssign reports whether assignment from src to dst can // be ignored by the escape analysis as it's effectively a self-assignment. func (e *EscState) isSelfAssign(dst, src *Node) bool { + if e.isSliceSelfAssign(dst, src) { + return true + } + + // Detect trivial assignments that assign back to the same object. + // + // It covers these cases: + // val.x = val.y + // val.x[i] = val.y[j] + // val.x1.x2 = val.x1.y2 + // ... etc + // + // These assignments do not change assigned object lifetime. + if dst == nil || src == nil || dst.Op != src.Op { return false } @@ -689,18 +751,16 @@ func (e *EscState) mayAffectMemory(n *Node) bool { switch n.Op { case ONAME, OCLOSUREVAR, OLITERAL: return false - case ODOT, ODOTPTR: - return e.mayAffectMemory(n.Left) - case OIND, OCONVNOP: - return e.mayAffectMemory(n.Left) - case OCONV: - return e.mayAffectMemory(n.Left) - case OINDEX: - return e.mayAffectMemory(n.Left) || e.mayAffectMemory(n.Right) - case OADD, OSUB, OOR, OXOR, OMUL, OLSH, ORSH, OAND, OANDNOT, ODIV, OMOD: + + // Left+Right group. + case OINDEX, OADD, OSUB, OOR, OXOR, OMUL, OLSH, ORSH, OAND, OANDNOT, ODIV, OMOD: return e.mayAffectMemory(n.Left) || e.mayAffectMemory(n.Right) - case ONOT, OCOM, OPLUS, OMINUS, OALIGNOF, OOFFSETOF, OSIZEOF: + + // Left group. + case ODOT, ODOTPTR, OIND, OCONVNOP, OCONV, OLEN, OCAP, + ONOT, OCOM, OPLUS, OMINUS, OALIGNOF, OOFFSETOF, OSIZEOF: return e.mayAffectMemory(n.Left) + default: return true } @@ -832,48 +892,8 @@ opSwitch: } } - // Filter out the following special case. - // - // func (b *Buffer) Foo() { - // n, m := ... - // b.buf = b.buf[n:m] - // } - // - // This assignment is a no-op for escape analysis, - // it does not store any new pointers into b that were not already there. - // However, without this special case b will escape, because we assign to OIND/ODOTPTR. case OAS, OASOP: - if (n.Left.Op == OIND || n.Left.Op == ODOTPTR) && n.Left.Left.Op == ONAME && // dst is ONAME dereference - (n.Right.Op == OSLICE || n.Right.Op == OSLICE3 || n.Right.Op == OSLICESTR) && // src is slice operation - (n.Right.Left.Op == OIND || n.Right.Left.Op == ODOTPTR) && n.Right.Left.Left.Op == ONAME && // slice is applied to ONAME dereference - n.Left.Left == n.Right.Left.Left { // dst and src reference the same base ONAME - - // Here we also assume that the statement will not contain calls, - // that is, that order will move any calls to init. - // Otherwise base ONAME value could change between the moments - // when we evaluate it for dst and for src. - // - // Note, this optimization does not apply to OSLICEARR, - // because it does introduce a new pointer into b that was not already there - // (pointer to b itself). After such assignment, if b contents escape, - // b escapes as well. If we ignore such OSLICEARR, we will conclude - // that b does not escape when b contents do. - if Debug['m'] != 0 { - Warnl(n.Pos, "%v ignoring self-assignment to %S", e.curfnSym(n), n.Left) - } - - break - } - - // Also skip trivial assignments that assign back to the same object. - // - // It covers these cases: - // val.x = val.y - // val.x[i] = val.y[j] - // val.x1.x2 = val.x1.y2 - // ... etc - // - // These assignments do not change assigned object lifetime. + // Filter out some no-op assignments for escape analysis. if e.isSelfAssign(n.Left, n.Right) { if Debug['m'] != 0 { Warnl(n.Pos, "%v ignoring self-assignment in %S", e.curfnSym(n), n) @@ -1396,7 +1416,7 @@ func describeEscape(em uint16) string { } s += "contentToHeap" } - for em >>= EscReturnBits; em != 0; em = em >> bitsPerOutputInTag { + for em >>= EscReturnBits; em != 0; em >>= bitsPerOutputInTag { // See encoding description above if s != "" { s += " " @@ -1446,7 +1466,7 @@ func (e *EscState) escassignfromtag(note string, dsts Nodes, src, call *Node) ui em0 := em dstsi := 0 - for em >>= EscReturnBits; em != 0 && dstsi < dsts.Len(); em = em >> bitsPerOutputInTag { + for em >>= EscReturnBits; em != 0 && dstsi < dsts.Len(); em >>= bitsPerOutputInTag { // Prefer the lowest-level path to the reference (for escape purposes). // Two-bit encoding (for example. 1, 3, and 4 bits are other options) // 01 = 0-level diff --git a/src/cmd/compile/internal/gc/export.go b/src/cmd/compile/internal/gc/export.go index 3aa7c39067..6ee660988a 100644 --- a/src/cmd/compile/internal/gc/export.go +++ b/src/cmd/compile/internal/gc/export.go @@ -12,8 +12,6 @@ import ( ) var ( - flagiexport bool // if set, use indexed export data format - Debug_export int // if set, print debugging information about export data ) @@ -75,11 +73,7 @@ func dumpexport(bout *bio.Writer) { // The linker also looks for the $$ marker - use char after $$ to distinguish format. exportf(bout, "\n$$B\n") // indicate binary export format off := bout.Offset() - if flagiexport { - iexport(bout.Writer) - } else { - export(bout.Writer, Debug_export != 0) - } + iexport(bout.Writer) size := bout.Offset() - off exportf(bout, "\n$$\n") @@ -95,7 +89,7 @@ func importsym(ipkg *types.Pkg, s *types.Sym, op Op) *Node { // declaration for all imported symbols. The exception // is declarations for Runtimepkg, which are populated // by loadsys instead. - if flagiexport && s.Pkg != Runtimepkg { + if s.Pkg != Runtimepkg { Fatalf("missing ONONAME for %v\n", s) } diff --git a/src/cmd/compile/internal/gc/float_test.go b/src/cmd/compile/internal/gc/float_test.go index c0a8cfc89e..c5c604003a 100644 --- a/src/cmd/compile/internal/gc/float_test.go +++ b/src/cmd/compile/internal/gc/float_test.go @@ -6,6 +6,8 @@ package gc import ( "math" + "os" + "runtime" "testing" ) @@ -364,11 +366,19 @@ func TestFloatConvertFolded(t *testing.T) { func TestFloat32StoreToLoadConstantFold(t *testing.T) { // Test that math.Float32{,from}bits constant fold correctly. - // In particular we need to be careful that signalling NaN (sNaN) values + // In particular we need to be careful that signaling NaN (sNaN) values // are not converted to quiet NaN (qNaN) values during compilation. // See issue #27193 for more information. - // signalling NaNs + // TODO: this method for detecting 387 won't work if the compiler has been + // built using GOARCH=386 GO386=387 and either the target is a different + // architecture or the GO386=387 environment variable is not set when the + // test is run. + if runtime.GOARCH == "386" && os.Getenv("GO386") == "387" { + t.Skip("signaling NaNs are not propagated on 387 (issue #27516)") + } + + // signaling NaNs { const nan = uint32(0x7f800001) // sNaN if x := math.Float32bits(math.Float32frombits(nan)); x != nan { diff --git a/src/cmd/compile/internal/gc/fmt.go b/src/cmd/compile/internal/gc/fmt.go index 5b7445d4db..5d2e36ee51 100644 --- a/src/cmd/compile/internal/gc/fmt.go +++ b/src/cmd/compile/internal/gc/fmt.go @@ -119,7 +119,7 @@ const ( // *types.Type: // %#v Go format // %#L type definition instead of name -// %#S omit"func" and receiver in function signature +// %#S omit "func" and receiver in function signature // // %-v type identifiers // %-S type identifiers without "func" and arg names in type signatures (methodsym) @@ -514,10 +514,10 @@ func (v Val) vconv(s fmt.State, flag FmtFlag) { case *Mpint: if !u.Rune { if flag&FmtSharp != 0 { - fmt.Fprint(s, bconv(u, FmtSharp)) + fmt.Fprint(s, u.String()) return } - fmt.Fprint(s, bconv(u, 0)) + fmt.Fprint(s, u.GoString()) return } @@ -537,29 +537,19 @@ func (v Val) vconv(s fmt.State, flag FmtFlag) { case *Mpflt: if flag&FmtSharp != 0 { - fmt.Fprint(s, fconv(u, 0)) + fmt.Fprint(s, u.String()) return } - fmt.Fprint(s, fconv(u, FmtSharp)) + fmt.Fprint(s, u.GoString()) return case *Mpcplx: - switch { - case flag&FmtSharp != 0: - fmt.Fprintf(s, "(%v+%vi)", &u.Real, &u.Imag) - - case v.U.(*Mpcplx).Real.CmpFloat64(0) == 0: - fmt.Fprintf(s, "%vi", fconv(&u.Imag, FmtSharp)) - - case v.U.(*Mpcplx).Imag.CmpFloat64(0) == 0: - fmt.Fprint(s, fconv(&u.Real, FmtSharp)) - - case v.U.(*Mpcplx).Imag.CmpFloat64(0) < 0: - fmt.Fprintf(s, "(%v%vi)", fconv(&u.Real, FmtSharp), fconv(&u.Imag, FmtSharp)) - - default: - fmt.Fprintf(s, "(%v+%vi)", fconv(&u.Real, FmtSharp), fconv(&u.Imag, FmtSharp)) + if flag&FmtSharp != 0 { + fmt.Fprint(s, u.String()) + return } + fmt.Fprint(s, u.GoString()) + return case string: fmt.Fprint(s, strconv.Quote(u)) @@ -671,7 +661,7 @@ func typefmt(t *types.Type, flag FmtFlag, mode fmtMode, depth int) string { return "error" } - // Unless the 'l' flag was specified, if the type has a name, just print that name. + // Unless the 'L' flag was specified, if the type has a name, just print that name. if flag&FmtLong == 0 && t.Sym != nil && t != types.Types[t.Etype] { switch mode { case FTypeId, FTypeIdName: @@ -1314,16 +1304,14 @@ func (n *Node) exprfmt(s fmt.State, prec int, mode fmtMode) { mode.Fprintf(s, "%v { %v }", n.Type, n.Func.Closure.Nbody) case OCOMPLIT: - ptrlit := n.Right != nil && n.Right.Implicit() && n.Right.Type != nil && n.Right.Type.IsPtr() if mode == FErr { if n.Right != nil && n.Right.Type != nil && !n.Implicit() { - if ptrlit { + if n.Right.Implicit() && n.Right.Type.IsPtr() { mode.Fprintf(s, "&%v literal", n.Right.Type.Elem()) return - } else { - mode.Fprintf(s, "%v literal", n.Right.Type) - return } + mode.Fprintf(s, "%v literal", n.Right.Type) + return } fmt.Fprint(s, "composite literal") @@ -1532,9 +1520,8 @@ func (n *Node) exprfmt(s fmt.State, prec int, mode fmtMode) { func (n *Node) nodefmt(s fmt.State, flag FmtFlag, mode fmtMode) { t := n.Type - // We almost always want the original, except in export mode for literals. - // This saves the importer some work, and avoids us having to redo some - // special casing for package unsafe. + // We almost always want the original. + // TODO(gri) Why the special case for OLITERAL? if n.Op != OLITERAL && n.Orig != nil { n = n.Orig } diff --git a/src/cmd/compile/internal/gc/inl.go b/src/cmd/compile/internal/gc/inl.go index fb5a413b84..f188c9a9cd 100644 --- a/src/cmd/compile/internal/gc/inl.go +++ b/src/cmd/compile/internal/gc/inl.go @@ -71,9 +71,7 @@ func fnpkg(fn *Node) *types.Pkg { func typecheckinl(fn *Node) { lno := setlineno(fn) - if flagiexport { - expandInline(fn) - } + expandInline(fn) // typecheckinl is only for imported functions; // their bodies may refer to unsafe as long as the package diff --git a/src/cmd/compile/internal/gc/main.go b/src/cmd/compile/internal/gc/main.go index 44cf75e7c9..68f6294724 100644 --- a/src/cmd/compile/internal/gc/main.go +++ b/src/cmd/compile/internal/gc/main.go @@ -249,7 +249,6 @@ func Main(archInit func(*Arch)) { flag.StringVar(&blockprofile, "blockprofile", "", "write block profile to `file`") flag.StringVar(&mutexprofile, "mutexprofile", "", "write mutex profile to `file`") flag.StringVar(&benchfile, "bench", "", "append benchmark times to `file`") - flag.BoolVar(&flagiexport, "iexport", true, "export indexed package data") objabi.Flagparse(usage) // Record flags that affect the build result. (And don't @@ -1129,24 +1128,13 @@ func importfile(f *Val) *types.Pkg { errorexit() } - // New indexed format is distinguished by an 'i' byte, - // whereas old export format always starts with 'c', 'd', or 'v'. - if c == 'i' { - if !flagiexport { - yyerror("import %s: cannot import package compiled with -iexport=true", file) - errorexit() - } - - iimport(importpkg, imp) - } else { - if flagiexport { - yyerror("import %s: cannot import package compiled with -iexport=false", file) - errorexit() - } - - imp.UnreadByte() - Import(importpkg, imp.Reader) + // Indexed format is distinguished by an 'i' byte, + // whereas previous export formats started with 'c', 'd', or 'v'. + if c != 'i' { + yyerror("import %s: unexpected package format byte: %v", file, c) + errorexit() } + iimport(importpkg, imp) default: yyerror("no import in %q", path_) diff --git a/src/cmd/compile/internal/gc/mpfloat.go b/src/cmd/compile/internal/gc/mpfloat.go index 5977ef9748..d1f5cb1200 100644 --- a/src/cmd/compile/internal/gc/mpfloat.go +++ b/src/cmd/compile/internal/gc/mpfloat.go @@ -201,24 +201,16 @@ func (a *Mpflt) SetString(as string) { } func (f *Mpflt) String() string { - return fconv(f, 0) + return f.Val.Text('b', 0) } -func fconv(fvp *Mpflt, flag FmtFlag) string { - if flag&FmtSharp == 0 { - return fvp.Val.Text('b', 0) - } - - // use decimal format for error messages - +func (fvp *Mpflt) GoString() string { // determine sign + sign := "" f := &fvp.Val - var sign string if f.Sign() < 0 { sign = "-" f = new(big.Float).Abs(f) - } else if flag&FmtSign != 0 { - sign = "+" } // Don't try to convert infinities (will not terminate). @@ -334,3 +326,34 @@ func (v *Mpcplx) Div(rv *Mpcplx) bool { return true } + +func (v *Mpcplx) String() string { + return fmt.Sprintf("(%s+%si)", v.Real.String(), v.Imag.String()) +} + +func (v *Mpcplx) GoString() string { + var re string + sre := v.Real.CmpFloat64(0) + if sre != 0 { + re = v.Real.GoString() + } + + var im string + sim := v.Imag.CmpFloat64(0) + if sim != 0 { + im = v.Imag.GoString() + } + + switch { + case sre == 0 && sim == 0: + return "0" + case sre == 0: + return im + "i" + case sim == 0: + return re + case sim < 0: + return fmt.Sprintf("(%s%si)", re, im) + default: + return fmt.Sprintf("(%s+%si)", re, im) + } +} diff --git a/src/cmd/compile/internal/gc/mpint.go b/src/cmd/compile/internal/gc/mpint.go index de47205435..e4dd22d0a0 100644 --- a/src/cmd/compile/internal/gc/mpint.go +++ b/src/cmd/compile/internal/gc/mpint.go @@ -299,13 +299,10 @@ func (a *Mpint) SetString(as string) { } } -func (a *Mpint) String() string { - return bconv(a, 0) +func (a *Mpint) GoString() string { + return a.Val.String() } -func bconv(xval *Mpint, flag FmtFlag) string { - if flag&FmtSharp != 0 { - return fmt.Sprintf("%#x", &xval.Val) - } - return xval.Val.String() +func (a *Mpint) String() string { + return fmt.Sprintf("%#x", &a.Val) } diff --git a/src/cmd/compile/internal/gc/obj.go b/src/cmd/compile/internal/gc/obj.go index fb749d171f..19862c03aa 100644 --- a/src/cmd/compile/internal/gc/obj.go +++ b/src/cmd/compile/internal/gc/obj.go @@ -281,7 +281,7 @@ func dumpglobls() { funcsyms = nil } -// addGCLocals adds gcargs and gclocals symbols to Ctxt.Data. +// addGCLocals adds gcargs, gclocals, gcregs, and stack object symbols to Ctxt.Data. // It takes care not to add any duplicates. // Though the object file format handles duplicates efficiently, // storing only a single copy of the data, @@ -299,6 +299,9 @@ func addGCLocals() { Ctxt.Data = append(Ctxt.Data, gcsym) seen[gcsym.Name] = true } + if x := s.Func.StackObjects; x != nil { + ggloblsym(x, int32(len(x.P)), obj.RODATA|obj.LOCAL) + } } } diff --git a/src/cmd/compile/internal/gc/op_string.go b/src/cmd/compile/internal/gc/op_string.go index 857234e45d..90b95d769f 100644 --- a/src/cmd/compile/internal/gc/op_string.go +++ b/src/cmd/compile/internal/gc/op_string.go @@ -4,9 +4,9 @@ package gc import "strconv" -const _Op_name = "XXXNAMENONAMETYPEPACKLITERALADDSUBORXORADDSTRADDRANDANDAPPENDARRAYBYTESTRARRAYBYTESTRTMPARRAYRUNESTRSTRARRAYBYTESTRARRAYBYTETMPSTRARRAYRUNEASAS2AS2FUNCAS2RECVAS2MAPRAS2DOTTYPEASOPCALLCALLFUNCCALLMETHCALLINTERCALLPARTCAPCLOSECLOSURECMPIFACECMPSTRCOMPLITMAPLITSTRUCTLITARRAYLITSLICELITPTRLITCONVCONVIFACECONVNOPCOPYDCLDCLFUNCDCLFIELDDCLCONSTDCLTYPEDELETEDOTDOTPTRDOTMETHDOTINTERXDOTDOTTYPEDOTTYPE2EQNELTLEGEGTINDINDEXINDEXMAPKEYSTRUCTKEYLENMAKEMAKECHANMAKEMAPMAKESLICEMULDIVMODLSHRSHANDANDNOTNEWNOTCOMPLUSMINUSORORPANICPRINTPRINTNPARENSENDSLICESLICEARRSLICESTRSLICE3SLICE3ARRRECOVERRECVRUNESTRSELRECVSELRECV2IOTAREALIMAGCOMPLEXALIGNOFOFFSETOFSIZEOFBLOCKBREAKCASEXCASECONTINUEDEFEREMPTYFALLFORFORUNTILGOTOIFLABELPROCRANGERETURNSELECTSWITCHTYPESWTCHANTMAPTSTRUCTTINTERTFUNCTARRAYDDDDDDARGINLCALLEFACEITABIDATASPTRCLOSUREVARCFUNCCHECKNILVARKILLVARLIVEINDREGSPRETJMPGETGEND" +const _Op_name = "XXXNAMENONAMETYPEPACKLITERALADDSUBORXORADDSTRADDRANDANDAPPENDARRAYBYTESTRARRAYBYTESTRTMPARRAYRUNESTRSTRARRAYBYTESTRARRAYBYTETMPSTRARRAYRUNEASAS2AS2FUNCAS2RECVAS2MAPRAS2DOTTYPEASOPCALLCALLFUNCCALLMETHCALLINTERCALLPARTCAPCLOSECLOSURECMPIFACECMPSTRCOMPLITMAPLITSTRUCTLITARRAYLITSLICELITPTRLITCONVCONVIFACECONVNOPCOPYDCLDCLFUNCDCLFIELDDCLCONSTDCLTYPEDELETEDOTDOTPTRDOTMETHDOTINTERXDOTDOTTYPEDOTTYPE2EQNELTLEGEGTINDINDEXINDEXMAPKEYSTRUCTKEYLENMAKEMAKECHANMAKEMAPMAKESLICEMULDIVMODLSHRSHANDANDNOTNEWNOTCOMPLUSMINUSORORPANICPRINTPRINTNPARENSENDSLICESLICEARRSLICESTRSLICE3SLICE3ARRRECOVERRECVRUNESTRSELRECVSELRECV2IOTAREALIMAGCOMPLEXALIGNOFOFFSETOFSIZEOFBLOCKBREAKCASEXCASECONTINUEDEFEREMPTYFALLFORFORUNTILGOTOIFLABELPROCRANGERETURNSELECTSWITCHTYPESWTCHANTMAPTSTRUCTTINTERTFUNCTARRAYDDDDDDARGINLCALLEFACEITABIDATASPTRCLOSUREVARCFUNCCHECKNILVARDEFVARKILLVARLIVEINDREGSPRETJMPGETGEND" -var _Op_index = [...]uint16{0, 3, 7, 13, 17, 21, 28, 31, 34, 36, 39, 45, 49, 55, 61, 73, 88, 100, 112, 127, 139, 141, 144, 151, 158, 165, 175, 179, 183, 191, 199, 208, 216, 219, 224, 231, 239, 245, 252, 258, 267, 275, 283, 289, 293, 302, 309, 313, 316, 323, 331, 339, 346, 352, 355, 361, 368, 376, 380, 387, 395, 397, 399, 401, 403, 405, 407, 410, 415, 423, 426, 435, 438, 442, 450, 457, 466, 469, 472, 475, 478, 481, 484, 490, 493, 496, 499, 503, 508, 512, 517, 522, 528, 533, 537, 542, 550, 558, 564, 573, 580, 584, 591, 598, 606, 610, 614, 618, 625, 632, 640, 646, 651, 656, 660, 665, 673, 678, 683, 687, 690, 698, 702, 704, 709, 713, 718, 724, 730, 736, 742, 747, 751, 758, 764, 769, 775, 778, 784, 791, 796, 800, 805, 809, 819, 824, 832, 839, 846, 854, 860, 864, 867} +var _Op_index = [...]uint16{0, 3, 7, 13, 17, 21, 28, 31, 34, 36, 39, 45, 49, 55, 61, 73, 88, 100, 112, 127, 139, 141, 144, 151, 158, 165, 175, 179, 183, 191, 199, 208, 216, 219, 224, 231, 239, 245, 252, 258, 267, 275, 283, 289, 293, 302, 309, 313, 316, 323, 331, 339, 346, 352, 355, 361, 368, 376, 380, 387, 395, 397, 399, 401, 403, 405, 407, 410, 415, 423, 426, 435, 438, 442, 450, 457, 466, 469, 472, 475, 478, 481, 484, 490, 493, 496, 499, 503, 508, 512, 517, 522, 528, 533, 537, 542, 550, 558, 564, 573, 580, 584, 591, 598, 606, 610, 614, 618, 625, 632, 640, 646, 651, 656, 660, 665, 673, 678, 683, 687, 690, 698, 702, 704, 709, 713, 718, 724, 730, 736, 742, 747, 751, 758, 764, 769, 775, 778, 784, 791, 796, 800, 805, 809, 819, 824, 832, 838, 845, 852, 860, 866, 870, 873} func (i Op) String() string { if i >= Op(len(_Op_index)-1) { diff --git a/src/cmd/compile/internal/gc/order.go b/src/cmd/compile/internal/gc/order.go index dce68a6c17..1e22ecfcdf 100644 --- a/src/cmd/compile/internal/gc/order.go +++ b/src/cmd/compile/internal/gc/order.go @@ -109,8 +109,7 @@ func (o *Order) cheapExpr(n *Node) *Node { if l == n.Left { return n } - a := n.copy() - a.Orig = a + a := n.sepcopy() a.Left = l return typecheck(a, Erv) } @@ -135,8 +134,7 @@ func (o *Order) safeExpr(n *Node) *Node { if l == n.Left { return n } - a := n.copy() - a.Orig = a + a := n.sepcopy() a.Left = l return typecheck(a, Erv) @@ -145,8 +143,7 @@ func (o *Order) safeExpr(n *Node) *Node { if l == n.Left { return n } - a := n.copy() - a.Orig = a + a := n.sepcopy() a.Left = l return typecheck(a, Erv) @@ -161,8 +158,7 @@ func (o *Order) safeExpr(n *Node) *Node { if l == n.Left && r == n.Right { return n } - a := n.copy() - a.Orig = a + a := n.sepcopy() a.Left = l a.Right = r return typecheck(a, Erv) diff --git a/src/cmd/compile/internal/gc/pgen.go b/src/cmd/compile/internal/gc/pgen.go index 563eb9e966..e6bbf04400 100644 --- a/src/cmd/compile/internal/gc/pgen.go +++ b/src/cmd/compile/internal/gc/pgen.go @@ -233,6 +233,26 @@ func compile(fn *Node) { // Set up the function's LSym early to avoid data races with the assemblers. fn.Func.initLSym() + // Make sure type syms are declared for all types that might + // be types of stack objects. We need to do this here + // because symbols must be allocated before the parallel + // phase of the compiler. + if fn.Func.lsym != nil { // not func _(){} + for _, n := range fn.Func.Dcl { + switch n.Class() { + case PPARAM, PPARAMOUT, PAUTO: + if livenessShouldTrack(n) && n.Addrtaken() { + dtypesym(n.Type) + // Also make sure we allocate a linker symbol + // for the stack object data, for the same reason. + if fn.Func.lsym.Func.StackObjects == nil { + fn.Func.lsym.Func.StackObjects = lookup(fmt.Sprintf("%s.stkobj", fn.funcname())).Linksym() + } + } + } + } + } + if compilenow() { compileSSA(fn, 0) } else { diff --git a/src/cmd/compile/internal/gc/plive.go b/src/cmd/compile/internal/gc/plive.go index e070a5cd1a..563b425db7 100644 --- a/src/cmd/compile/internal/gc/plive.go +++ b/src/cmd/compile/internal/gc/plive.go @@ -78,6 +78,10 @@ import ( // that its argument is certainly dead, for use when the liveness analysis // would not otherwise be able to deduce that fact. +// TODO: get rid of OpVarKill here. It's useful for stack frame allocation +// so the compiler can allocate two temps to the same location. Here it's now +// useless, since the implementation of stack objects. + // BlockEffects summarizes the liveness effects on an SSA block. type BlockEffects struct { // Computed during Liveness.prologue using only the content of @@ -85,23 +89,15 @@ type BlockEffects struct { // // uevar: upward exposed variables (used before set in block) // varkill: killed variables (set in block) - // avarinit: addrtaken variables set or used (proof of initialization) - uevar varRegVec - varkill varRegVec - avarinit bvec + uevar varRegVec + varkill varRegVec // Computed during Liveness.solve using control flow information: // // livein: variables live at block entry // liveout: variables live at block exit - // avarinitany: addrtaken variables possibly initialized at block exit - // (initialized in block or at exit from any predecessor block) - // avarinitall: addrtaken variables certainly initialized at block exit - // (initialized in block or at exit from all predecessor blocks) - livein varRegVec - liveout varRegVec - avarinitany bvec - avarinitall bvec + livein varRegVec + liveout varRegVec } // A collection of global state used by liveness analysis. @@ -186,10 +182,9 @@ func (idx LivenessIndex) Valid() bool { } type progeffectscache struct { - textavarinit []int32 - retuevar []int32 - tailuevar []int32 - initialized bool + retuevar []int32 + tailuevar []int32 + initialized bool } // varRegVec contains liveness bitmaps for variables and registers. @@ -264,24 +259,13 @@ func (lv *Liveness) initcache() { // all the parameters for correctness, and similarly it must not // read the out arguments - they won't be set until the new // function runs. - lv.cache.tailuevar = append(lv.cache.tailuevar, int32(i)) - if node.Addrtaken() { - lv.cache.textavarinit = append(lv.cache.textavarinit, int32(i)) - } - case PPARAMOUT: - // If the result had its address taken, it is being tracked - // by the avarinit code, which does not use uevar. - // If we added it to uevar too, we'd not see any kill - // and decide that the variable was live entry, which it is not. - // So only use uevar in the non-addrtaken case. - // The p.to.type == obj.TYPE_NONE limits the bvset to - // non-tail-call return instructions; see note below for details. - if !node.Addrtaken() { - lv.cache.retuevar = append(lv.cache.retuevar, int32(i)) - } + // All results are live at every return point. + // Note that this point is after escaping return values + // are copied back to the stack using their PAUTOHEAP references. + lv.cache.retuevar = append(lv.cache.retuevar, int32(i)) } } } @@ -291,21 +275,13 @@ func (lv *Liveness) initcache() { // // The possible flags are: // uevar - used by the instruction -// varkill - killed by the instruction -// for variables without address taken, means variable was set -// for variables with address taken, means variable was marked dead -// avarinit - initialized or referred to by the instruction, -// only for variables with address taken but not escaping to heap -// -// The avarinit output serves as a signal that the data has been -// initialized, because any use of a variable must come after its -// initialization. +// varkill - killed by the instruction (set) +// A kill happens after the use (for an instruction that updates a value, for example). type liveEffect int const ( uevar liveEffect = 1 << iota varkill - avarinit ) // valueEffects returns the index of a variable in lv.vars and the @@ -329,27 +305,15 @@ func (lv *Liveness) valueEffects(v *ssa.Value) (int32, liveEffect) { } var effect liveEffect - if n.Addrtaken() { - if v.Op != ssa.OpVarKill { - effect |= avarinit - } - if v.Op == ssa.OpVarDef || v.Op == ssa.OpVarKill { - effect |= varkill - } - } else { - // Read is a read, obviously. - // Addr by itself is also implicitly a read. - // - // Addr|Write means that the address is being taken - // but only so that the instruction can write to the value. - // It is not a read. - - if e&ssa.SymRead != 0 || e&(ssa.SymAddr|ssa.SymWrite) == ssa.SymAddr { - effect |= uevar - } - if e&ssa.SymWrite != 0 && (!isfat(n.Type) || v.Op == ssa.OpVarDef) { - effect |= varkill - } + // Read is a read, obviously. + // + // Addr is a read also, as any subseqent holder of the pointer must be able + // to see all the values (including initialization) written so far. + if e&(ssa.SymRead|ssa.SymAddr) != 0 { + effect |= uevar + } + if e&ssa.SymWrite != 0 && (!isfat(n.Type) || v.Op == ssa.OpVarDef) { + effect |= varkill } if effect == 0 { @@ -545,9 +509,6 @@ func newliveness(fn *Node, f *ssa.Func, vars []*Node, idx map[*Node]int32, stkpt be.varkill = varRegVec{vars: bulk.next()} be.livein = varRegVec{vars: bulk.next()} be.liveout = varRegVec{vars: bulk.next()} - be.avarinit = bulk.next() - be.avarinitany = bulk.next() - be.avarinitall = bulk.next() } lv.livenessMap.reset(lv.f.NumValues()) @@ -869,19 +830,6 @@ func (lv *Liveness) prologue() { } be.uevar.regs |= regUevar } - - // Walk the block instructions forward to update avarinit bits. - // avarinit describes the effect at the end of the block, not the beginning. - for _, val := range b.Values { - pos, e := lv.valueEffects(val) - // No need for regEffects because registers never appear in avarinit. - if e&varkill != 0 { - be.avarinit.Unset(pos) - } - if e&avarinit != 0 { - be.avarinit.Set(pos) - } - } } } @@ -892,51 +840,10 @@ func (lv *Liveness) solve() { nvars := int32(len(lv.vars)) newlivein := varRegVec{vars: bvalloc(nvars)} newliveout := varRegVec{vars: bvalloc(nvars)} - any := bvalloc(nvars) - all := bvalloc(nvars) - // Push avarinitall, avarinitany forward. - // avarinitall says the addressed var is initialized along all paths reaching the block exit. - // avarinitany says the addressed var is initialized along some path reaching the block exit. - for _, b := range lv.f.Blocks { - be := lv.blockEffects(b) - if b == lv.f.Entry { - be.avarinitall.Copy(be.avarinit) - } else { - be.avarinitall.Clear() - be.avarinitall.Not() - } - be.avarinitany.Copy(be.avarinit) - } - - // Walk blocks in the general direction of propagation (RPO - // for avarinit{any,all}, and PO for live{in,out}). This - // improves convergence. + // Walk blocks in postorder ordering. This improves convergence. po := lv.f.Postorder() - for change := true; change; { - change = false - for i := len(po) - 1; i >= 0; i-- { - b := po[i] - be := lv.blockEffects(b) - lv.avarinitanyall(b, any, all) - - any.AndNot(any, be.varkill.vars) - all.AndNot(all, be.varkill.vars) - any.Or(any, be.avarinit) - all.Or(all, be.avarinit) - if !any.Eq(be.avarinitany) { - change = true - be.avarinitany.Copy(any) - } - - if !all.Eq(be.avarinitall) { - change = true - be.avarinitall.Copy(all) - } - } - } - // Iterate through the blocks in reverse round-robin fashion. A work // queue might be slightly faster. As is, the number of iterations is // so low that it hardly seems to be worth the complexity. @@ -957,7 +864,7 @@ func (lv *Liveness) solve() { newliveout.vars.Set(pos) } case ssa.BlockExit: - // nothing to do + // panic exit - nothing to do default: // A variable is live on output from this block // if it is live on input to some successor. @@ -975,7 +882,7 @@ func (lv *Liveness) solve() { } // A variable is live on input to this block - // if it is live on output from this block and + // if it is used by this block, or live on output from this block and // not set by the code in this block. // // in[b] = uevar[b] \cup (out[b] \setminus varkill[b]) @@ -990,8 +897,6 @@ func (lv *Liveness) solve() { func (lv *Liveness) epilogue() { nvars := int32(len(lv.vars)) liveout := varRegVec{vars: bvalloc(nvars)} - any := bvalloc(nvars) - all := bvalloc(nvars) livedefer := bvalloc(nvars) // always-live variables // If there is a defer (that could recover), then all output @@ -1017,6 +922,9 @@ func (lv *Liveness) epilogue() { livedefer.Set(int32(i)) } if n.IsOutputParamHeapAddr() { + // This variable will be overwritten early in the function + // prologue (from the result of a mallocgc) but we need to + // zero it in case that malloc causes a stack scan. n.Name.SetNeedzero(true) livedefer.Set(int32(i)) } @@ -1033,9 +941,6 @@ func (lv *Liveness) epilogue() { { // Reserve an entry for function entry. live := bvalloc(nvars) - for _, pos := range lv.cache.textavarinit { - live.Set(pos) - } lv.livevars = append(lv.livevars, varRegVec{vars: live}) } @@ -1043,53 +948,14 @@ func (lv *Liveness) epilogue() { be := lv.blockEffects(b) firstBitmapIndex := len(lv.livevars) - // Compute avarinitany and avarinitall for entry to block. - // This duplicates information known during Liveness.solve - // but avoids storing two more vectors for each block. - lv.avarinitanyall(b, any, all) - // Walk forward through the basic block instructions and // allocate liveness maps for those instructions that need them. - // Seed the maps with information about the addrtaken variables. for _, v := range b.Values { - pos, e := lv.valueEffects(v) - // No need for regEffects because registers never appear in avarinit. - if e&varkill != 0 { - any.Unset(pos) - all.Unset(pos) - } - if e&avarinit != 0 { - any.Set(pos) - all.Set(pos) - } - if !lv.issafepoint(v) { continue } - // Annotate ambiguously live variables so that they can - // be zeroed at function entry and at VARKILL points. - // liveout is dead here and used as a temporary. - liveout.vars.AndNot(any, all) - if !liveout.vars.IsEmpty() { - for pos := int32(0); pos < liveout.vars.n; pos++ { - if !liveout.vars.Get(pos) { - continue - } - all.Set(pos) // silence future warnings in this block - n := lv.vars[pos] - if !n.Name.Needzero() { - n.Name.SetNeedzero(true) - if debuglive >= 1 { - Warnl(v.Pos, "%v: %L is ambiguously live", lv.fn.Func.Nname, n) - } - } - } - } - - // Live stuff first. live := bvalloc(nvars) - live.Copy(any) lv.livevars = append(lv.livevars, varRegVec{vars: live}) } @@ -1128,6 +994,17 @@ func (lv *Liveness) epilogue() { Fatalf("bad index for entry point: %v", index) } + // Check to make sure only input variables are live. + for i, n := range lv.vars { + if !liveout.vars.Get(int32(i)) { + continue + } + if n.Class() == PPARAM { + continue // ok + } + Fatalf("bad live variable at entry of %v: %L", lv.fn.Func.Nname, n) + } + // Record live variables. live := &lv.livevars[index] live.Or(*live, liveout) @@ -1330,28 +1207,6 @@ func clobberPtr(b *ssa.Block, v *Node, offset int64) { b.NewValue0IA(src.NoXPos, ssa.OpClobber, types.TypeVoid, offset, v) } -func (lv *Liveness) avarinitanyall(b *ssa.Block, any, all bvec) { - if len(b.Preds) == 0 { - any.Clear() - all.Clear() - for _, pos := range lv.cache.textavarinit { - any.Set(pos) - all.Set(pos) - } - return - } - - be := lv.blockEffects(b.Preds[0].Block()) - any.Copy(be.avarinitany) - all.Copy(be.avarinitall) - - for _, pred := range b.Preds[1:] { - be := lv.blockEffects(pred.Block()) - any.Or(any, be.avarinitany) - all.And(all, be.avarinitall) - } -} - // Compact coalesces identical bitmaps from lv.livevars into the sets // lv.stackMapSet and lv.regMaps. // @@ -1559,7 +1414,6 @@ func (lv *Liveness) printDebug() { printed = false printed = lv.printeffect(printed, "uevar", pos, effect&uevar != 0, regUevar) printed = lv.printeffect(printed, "varkill", pos, effect&varkill != 0, regKill) - printed = lv.printeffect(printed, "avarinit", pos, effect&avarinit != 0, 0) if printed { fmt.Printf("\n") } @@ -1596,9 +1450,6 @@ func (lv *Liveness) printDebug() { printed = false printed = lv.printbvec(printed, "varkill", be.varkill) printed = lv.printbvec(printed, "liveout", be.liveout) - printed = lv.printbvec(printed, "avarinit", varRegVec{vars: be.avarinit}) - printed = lv.printbvec(printed, "avarinitany", varRegVec{vars: be.avarinitany}) - printed = lv.printbvec(printed, "avarinitall", varRegVec{vars: be.avarinitall}) if printed { fmt.Printf("\n") } diff --git a/src/cmd/compile/internal/gc/sinit.go b/src/cmd/compile/internal/gc/sinit.go index c6455c3693..9d1114fa43 100644 --- a/src/cmd/compile/internal/gc/sinit.go +++ b/src/cmd/compile/internal/gc/sinit.go @@ -349,15 +349,13 @@ func staticcopy(l *Node, r *Node, out *[]*Node) bool { gdata(n, e.Expr, int(n.Type.Width)) continue } - ll := n.copy() - ll.Orig = ll // completely separate copy + ll := n.sepcopy() if staticassign(ll, e.Expr, out) { continue } // Requires computation, but we're // copying someone else's computation. - rr := orig.copy() - rr.Orig = rr // completely separate copy + rr := orig.sepcopy() rr.Type = ll.Type rr.Xoffset += e.Xoffset setlineno(rr) @@ -453,8 +451,7 @@ func staticassign(l *Node, r *Node, out *[]*Node) bool { continue } setlineno(e.Expr) - a := n.copy() - a.Orig = a // completely separate copy + a := n.sepcopy() if !staticassign(a, e.Expr, out) { *out = append(*out, nod(OAS, a, e.Expr)) } @@ -518,8 +515,7 @@ func staticassign(l *Node, r *Node, out *[]*Node) bool { // Copy val directly into n. n.Type = val.Type setlineno(val) - a := n.copy() - a.Orig = a + a := n.sepcopy() if !staticassign(a, val, out) { *out = append(*out, nod(OAS, a, val)) } @@ -843,6 +839,10 @@ func slicelit(ctxt initContext, n *Node, var_ *Node, init *Nodes) { a = nod(OAS, x, nil) a = typecheck(a, Etop) init.Append(a) // zero new temp + } else { + // Declare that we're about to initialize all of x. + // (Which happens at the *vauto = vstat below.) + init.Append(nod(OVARDEF, x, nil)) } a = nod(OADDR, x, nil) @@ -853,6 +853,8 @@ func slicelit(ctxt initContext, n *Node, var_ *Node, init *Nodes) { a = typecheck(a, Etop) init.Append(a) // zero new temp a = a.Left + } else { + init.Append(nod(OVARDEF, a, nil)) } a = nod(OADDR, a, nil) diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go index 00ff7d4bd5..138ce08fec 100644 --- a/src/cmd/compile/internal/gc/ssa.go +++ b/src/cmd/compile/internal/gc/ssa.go @@ -16,6 +16,7 @@ import ( "cmd/compile/internal/ssa" "cmd/compile/internal/types" "cmd/internal/obj" + "cmd/internal/objabi" "cmd/internal/src" "cmd/internal/sys" ) @@ -754,8 +755,8 @@ func (s *state) stmtList(l Nodes) { // stmt converts the statement n to SSA and adds it to s. func (s *state) stmt(n *Node) { - if !(n.Op == OVARKILL || n.Op == OVARLIVE) { - // OVARKILL and OVARLIVE are invisible to the programmer, so we don't use their line numbers to avoid confusion in debugging. + if !(n.Op == OVARKILL || n.Op == OVARLIVE || n.Op == OVARDEF) { + // OVARKILL, OVARLIVE, and OVARDEF are invisible to the programmer, so we don't use their line numbers to avoid confusion in debugging. s.pushLine(n.Pos) defer s.popLine() } @@ -1169,6 +1170,10 @@ func (s *state) stmt(n *Node) { } s.startBlock(bEnd) + case OVARDEF: + if !s.canSSA(n.Left) { + s.vars[&memVar] = s.newValue1Apos(ssa.OpVarDef, types.TypeMem, n.Left, s.mem(), false) + } case OVARKILL: // Insert a varkill op to record that a variable is no longer live. // We only care about liveness info at call sites, so putting the @@ -3149,12 +3154,12 @@ func init() { func(s *state, n *Node, args []*ssa.Value) *ssa.Value { return s.newValue1(ssa.OpRoundToEven, types.Types[TFLOAT64], args[0]) }, - sys.S390X) + sys.ARM64, sys.S390X) addF("math", "Abs", func(s *state, n *Node, args []*ssa.Value) *ssa.Value { return s.newValue1(ssa.OpAbs, types.Types[TFLOAT64], args[0]) }, - sys.PPC64) + sys.ARM64, sys.PPC64) addF("math", "Copysign", func(s *state, n *Node, args []*ssa.Value) *ssa.Value { return s.newValue2(ssa.OpCopysign, types.Types[TFLOAT64], args[0], args[1]) @@ -3361,12 +3366,12 @@ func init() { func(s *state, n *Node, args []*ssa.Value) *ssa.Value { return s.newValue2(ssa.OpRotateLeft32, types.Types[TUINT32], args[0], args[1]) }, - sys.AMD64, sys.S390X) + sys.AMD64, sys.ARM64, sys.S390X) addF("math/bits", "RotateLeft64", func(s *state, n *Node, args []*ssa.Value) *ssa.Value { return s.newValue2(ssa.OpRotateLeft64, types.Types[TUINT64], args[0], args[1]) }, - sys.AMD64, sys.S390X) + sys.AMD64, sys.ARM64, sys.S390X) alias("math/bits", "RotateLeft", "math/bits", "RotateLeft64", p8...) makeOnesCountAMD64 := func(op64 ssa.Op, op32 ssa.Op) func(s *state, n *Node, args []*ssa.Value) *ssa.Value { @@ -3435,6 +3440,12 @@ func init() { addF("math/bits", "OnesCount", makeOnesCountAMD64(ssa.OpPopCount64, ssa.OpPopCount32), sys.AMD64) + alias("math/bits", "Mul", "math/bits", "Mul64", sys.ArchAMD64, sys.ArchARM64, sys.ArchPPC64) + addF("math/bits", "Mul64", + func(s *state, n *Node, args []*ssa.Value) *ssa.Value { + return s.newValue2(ssa.OpMul64uhilo, types.NewTuple(types.Types[TUINT64], types.Types[TUINT64]), args[0], args[1]) + }, + sys.AMD64, sys.ARM64, sys.PPC64) /******** sync/atomic ********/ @@ -4927,6 +4938,57 @@ func (s *SSAGenState) DebugFriendlySetPosFrom(v *ssa.Value) { } } +// byXoffset implements sort.Interface for []*Node using Xoffset as the ordering. +type byXoffset []*Node + +func (s byXoffset) Len() int { return len(s) } +func (s byXoffset) Less(i, j int) bool { return s[i].Xoffset < s[j].Xoffset } +func (s byXoffset) Swap(i, j int) { s[i], s[j] = s[j], s[i] } + +func emitStackObjects(e *ssafn, pp *Progs) { + var vars []*Node + for _, n := range e.curfn.Func.Dcl { + if livenessShouldTrack(n) && n.Addrtaken() { + vars = append(vars, n) + } + } + if len(vars) == 0 { + return + } + + // Sort variables from lowest to highest address. + sort.Sort(byXoffset(vars)) + + // Populate the stack object data. + // Format must match runtime/stack.go:stackObjectRecord. + x := e.curfn.Func.lsym.Func.StackObjects + off := 0 + off = duintptr(x, off, uint64(len(vars))) + for _, v := range vars { + // Note: arguments and return values have non-negative Xoffset, + // in which case the offset is relative to argp. + // Locals have a negative Xoffset, in which case the offset is relative to varp. + off = duintptr(x, off, uint64(v.Xoffset)) + if !typesym(v.Type).Siggen() { + Fatalf("stack object's type symbol not generated for type %s", v.Type) + } + off = dsymptr(x, off, dtypesym(v.Type), 0) + } + + // Emit a funcdata pointing at the stack object data. + p := pp.Prog(obj.AFUNCDATA) + Addrconst(&p.From, objabi.FUNCDATA_StackObjects) + p.To.Type = obj.TYPE_MEM + p.To.Name = obj.NAME_EXTERN + p.To.Sym = x + + if debuglive != 0 { + for _, v := range vars { + Warnl(v.Pos, "stack object %v %s", v, v.Type.String()) + } + } +} + // genssa appends entries to pp for each instruction in f. func genssa(f *ssa.Func, pp *Progs) { var s SSAGenState @@ -4934,6 +4996,7 @@ func genssa(f *ssa.Func, pp *Progs) { e := f.Frontend().(*ssafn) s.livenessMap = liveness(e, f) + emitStackObjects(e, pp) // Remember where each block starts. s.bstart = make([]*obj.Prog, f.NumBlocks()) @@ -5003,24 +5066,8 @@ func genssa(f *ssa.Func, pp *Progs) { case ssa.OpGetG: // nothing to do when there's a g register, // and checkLower complains if there's not - case ssa.OpVarDef, ssa.OpVarLive, ssa.OpKeepAlive: + case ssa.OpVarDef, ssa.OpVarLive, ssa.OpKeepAlive, ssa.OpVarKill: // nothing to do; already used by liveness - case ssa.OpVarKill: - // Zero variable if it is ambiguously live. - // After the VARKILL anything this variable references - // might be collected. If it were to become live again later, - // the GC will see references to already-collected objects. - // See issue 20029. - n := v.Aux.(*Node) - if n.Name.Needzero() { - if n.Class() != PAUTO { - v.Fatalf("zero of variable which isn't PAUTO %v", n) - } - if n.Type.Size()%int64(Widthptr) != 0 { - v.Fatalf("zero of variable not a multiple of ptr size %v", n) - } - thearch.ZeroAuto(s.pp, n) - } case ssa.OpPhi: CheckLoweredPhi(v) case ssa.OpConvert: @@ -5048,7 +5095,6 @@ func genssa(f *ssa.Func, pp *Progs) { } } } - // Emit control flow instructions for block var next *ssa.Block if i < len(f.Blocks)-1 && Debug['N'] == 0 { diff --git a/src/cmd/compile/internal/gc/subr.go b/src/cmd/compile/internal/gc/subr.go index 61a3b2385d..7e450e2e66 100644 --- a/src/cmd/compile/internal/gc/subr.go +++ b/src/cmd/compile/internal/gc/subr.go @@ -364,9 +364,35 @@ func nodSym(op Op, left *Node, sym *types.Sym) *Node { return n } +// rawcopy returns a shallow copy of n. +// Note: copy or sepcopy (rather than rawcopy) is usually the +// correct choice (see comment with Node.copy, below). +func (n *Node) rawcopy() *Node { + copy := *n + return © +} + +// sepcopy returns a separate shallow copy of n, with the copy's +// Orig pointing to itself. +func (n *Node) sepcopy() *Node { + copy := *n + copy.Orig = © + return © +} + +// copy returns shallow copy of n and adjusts the copy's Orig if +// necessary: In general, if n.Orig points to itself, the copy's +// Orig should point to itself as well. Otherwise, if n is modified, +// the copy's Orig node appears modified, too, and then doesn't +// represent the original node anymore. +// (This caused the wrong complit Op to be used when printing error +// messages; see issues #26855, #27765). func (n *Node) copy() *Node { - n2 := *n - return &n2 + copy := *n + if n.Orig == n { + copy.Orig = © + } + return © } // methcmp sorts methods by symbol. @@ -412,8 +438,7 @@ func treecopy(n *Node, pos src.XPos) *Node { switch n.Op { default: - m := n.copy() - m.Orig = m + m := n.sepcopy() m.Left = treecopy(n.Left, pos) m.Right = treecopy(n.Right, pos) m.List.Set(listtreecopy(n.List.Slice(), pos)) diff --git a/src/cmd/compile/internal/gc/syntax.go b/src/cmd/compile/internal/gc/syntax.go index df23b83f29..eb2ab6b916 100644 --- a/src/cmd/compile/internal/gc/syntax.go +++ b/src/cmd/compile/internal/gc/syntax.go @@ -739,6 +739,7 @@ const ( OCLOSUREVAR // variable reference at beginning of closure function OCFUNC // reference to c function pointer (not go func value) OCHECKNIL // emit code to ensure pointer/interface not nil + OVARDEF // variable is about to be fully initialized OVARKILL // variable is dead OVARLIVE // variable is alive OINDREGSP // offset plus indirect of REGSP, such as 8(SP). diff --git a/src/cmd/compile/internal/gc/typecheck.go b/src/cmd/compile/internal/gc/typecheck.go index bb78d8bf73..4831ecca34 100644 --- a/src/cmd/compile/internal/gc/typecheck.go +++ b/src/cmd/compile/internal/gc/typecheck.go @@ -2436,7 +2436,7 @@ func isMethodApplicable(t *types.Type, m *types.Field) bool { } func derefall(t *types.Type) *types.Type { - for t != nil && t.Etype == types.Tptr { + for t != nil && t.IsPtr() { t = t.Elem() } return t @@ -2506,20 +2506,20 @@ func lookdot(n *Node, t *types.Type, dostrcmp int) *types.Field { dowidth(tt) rcvr := f2.Type.Recv().Type if !eqtype(rcvr, tt) { - if rcvr.Etype == types.Tptr && eqtype(rcvr.Elem(), tt) { + if rcvr.IsPtr() && eqtype(rcvr.Elem(), tt) { checklvalue(n.Left, "call pointer method on") n.Left = nod(OADDR, n.Left, nil) n.Left.SetImplicit(true) n.Left = typecheck(n.Left, Etype|Erv) - } else if tt.Etype == types.Tptr && rcvr.Etype != types.Tptr && eqtype(tt.Elem(), rcvr) { + } else if tt.IsPtr() && !rcvr.IsPtr() && eqtype(tt.Elem(), rcvr) { n.Left = nod(OIND, n.Left, nil) n.Left.SetImplicit(true) n.Left = typecheck(n.Left, Etype|Erv) - } else if tt.Etype == types.Tptr && tt.Elem().Etype == types.Tptr && eqtype(derefall(tt), derefall(rcvr)) { + } else if tt.IsPtr() && tt.Elem().IsPtr() && eqtype(derefall(tt), derefall(rcvr)) { yyerror("calling method %v with receiver %L requires explicit dereference", n.Sym, n.Left) - for tt.Etype == types.Tptr { + for tt.IsPtr() { // Stop one level early for method with pointer receiver. - if rcvr.Etype == types.Tptr && tt.Elem().Etype != types.Tptr { + if rcvr.IsPtr() && !tt.Elem().IsPtr() { break } n.Left = nod(OIND, n.Left, nil) @@ -3298,7 +3298,8 @@ func samesafeexpr(l *Node, r *Node) bool { case ODOT, ODOTPTR: return l.Sym != nil && r.Sym != nil && l.Sym == r.Sym && samesafeexpr(l.Left, r.Left) - case OIND, OCONVNOP: + case OIND, OCONVNOP, + ONOT, OCOM, OPLUS, OMINUS: return samesafeexpr(l.Left, r.Left) case OCONV: @@ -3306,7 +3307,8 @@ func samesafeexpr(l *Node, r *Node) bool { // Allow only numeric-ish types. This is a bit conservative. return issimple[l.Type.Etype] && samesafeexpr(l.Left, r.Left) - case OINDEX, OINDEXMAP: + case OINDEX, OINDEXMAP, + OADD, OSUB, OOR, OXOR, OMUL, OLSH, ORSH, OAND, OANDNOT, ODIV, OMOD: return samesafeexpr(l.Left, r.Left) && samesafeexpr(l.Right, r.Right) case OLITERAL: @@ -3339,7 +3341,7 @@ func typecheckas(n *Node) { checkassign(n, n.Left) if n.Right != nil && n.Right.Type != nil { if n.Right.Type.IsFuncArgStruct() { - yyerror("assignment mismatch: 1 variable but %d values", n.Right.Type.NumFields()) + yyerror("assignment mismatch: 1 variable but %v returns %d values", n.Right.Left, n.Right.Type.NumFields()) // Multi-value RHS isn't actually valid for OAS; nil out // to indicate failed typechecking. n.Right.Type = nil @@ -3484,7 +3486,12 @@ func typecheckas2(n *Node) { } mismatch: - yyerror("assignment mismatch: %d variables but %d values", cl, cr) + switch r.Op { + default: + yyerror("assignment mismatch: %d variable but %d values", cl, cr) + case OCALLFUNC, OCALLMETH, OCALLINTER: + yyerror("assignment mismatch: %d variables but %v returns %d values", cl, r.Left, cr) + } // second half of dance out: @@ -3640,25 +3647,22 @@ func typecheckdeftype(n *Node) { } func typecheckdef(n *Node) { - lno := lineno - setlineno(n) + lno := setlineno(n) if n.Op == ONONAME { if !n.Diag() { n.SetDiag(true) - if n.Pos.IsKnown() { - lineno = n.Pos - } // Note: adderrorname looks for this string and // adds context about the outer expression - yyerror("undefined: %v", n.Sym) + yyerrorl(lineno, "undefined: %v", n.Sym) } - + lineno = lno return } if n.Walkdef() == 1 { + lineno = lno return } @@ -3701,20 +3705,19 @@ func typecheckdef(n *Node) { e := n.Name.Defn n.Name.Defn = nil if e == nil { - lineno = n.Pos Dump("typecheckdef nil defn", n) - yyerror("xxx") + yyerrorl(n.Pos, "xxx") } e = typecheck(e, Erv) if Isconst(e, CTNIL) { - yyerror("const initializer cannot be nil") + yyerrorl(n.Pos, "const initializer cannot be nil") goto ret } if e.Type != nil && e.Op != OLITERAL || !e.isGoConst() { if !e.Diag() { - yyerror("const initializer %v is not a constant", e) + yyerrorl(n.Pos, "const initializer %v is not a constant", e) e.SetDiag(true) } @@ -3724,12 +3727,12 @@ func typecheckdef(n *Node) { t := n.Type if t != nil { if !okforconst[t.Etype] { - yyerror("invalid constant type %v", t) + yyerrorl(n.Pos, "invalid constant type %v", t) goto ret } if !e.Type.IsUntyped() && !eqtype(t, e.Type) { - yyerror("cannot use %L as type %v in const initializer", e, t) + yyerrorl(n.Pos, "cannot use %L as type %v in const initializer", e, t) goto ret } diff --git a/src/cmd/compile/internal/gc/walk.go b/src/cmd/compile/internal/gc/walk.go index 2993e08fc2..1b1d36b61d 100644 --- a/src/cmd/compile/internal/gc/walk.go +++ b/src/cmd/compile/internal/gc/walk.go @@ -1312,7 +1312,7 @@ opswitch: b = conv(b, convType) b = nod(OLSH, b, nodintconst(int64(8*offset))) ncsubstr = nod(OOR, ncsubstr, b) - csubstr = csubstr | int64(s[i+offset])<<uint8(8*offset) + csubstr |= int64(s[i+offset]) << uint8(8*offset) } csubstrPart := nodintconst(csubstr) // Compare "step" bytes as once @@ -1418,7 +1418,7 @@ opswitch: // Maximum key and value size is 128 bytes, larger objects // are stored with an indirection. So max bucket size is 2048+eps. if !Isconst(hint, CTINT) || - !(hint.Val().U.(*Mpint).CmpInt64(BUCKETSIZE) > 0) { + hint.Val().U.(*Mpint).CmpInt64(BUCKETSIZE) <= 0 { // var bv bmap bv := temp(bmap(t)) @@ -4052,7 +4052,7 @@ func wrapCall(n *Node, init *Nodes) *Node { // The result of substArgTypes MUST be assigned back to old, e.g. // n.Left = substArgTypes(n.Left, t1, t2) func substArgTypes(old *Node, types_ ...*types.Type) *Node { - n := old.copy() // make shallow copy + n := old.copy() for _, t := range types_ { dowidth(t) diff --git a/src/cmd/compile/internal/ppc64/ssa.go b/src/cmd/compile/internal/ppc64/ssa.go index fd226a2e98..0a7238850c 100644 --- a/src/cmd/compile/internal/ppc64/ssa.go +++ b/src/cmd/compile/internal/ppc64/ssa.go @@ -153,6 +153,24 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.To.Reg = y } + case ssa.OpPPC64LoweredMuluhilo: + // MULHDU Rarg1, Rarg0, Reg0 + // MULLD Rarg1, Rarg0, Reg1 + r0 := v.Args[0].Reg() + r1 := v.Args[1].Reg() + p := s.Prog(ppc64.AMULHDU) + p.From.Type = obj.TYPE_REG + p.From.Reg = r1 + p.Reg = r0 + p.To.Type = obj.TYPE_REG + p.To.Reg = v.Reg0() + p1 := s.Prog(ppc64.AMULLD) + p1.From.Type = obj.TYPE_REG + p1.From.Reg = r1 + p1.Reg = r0 + p1.To.Type = obj.TYPE_REG + p1.To.Reg = v.Reg1() + case ssa.OpPPC64LoweredAtomicAnd8, ssa.OpPPC64LoweredAtomicOr8: // LWSYNC @@ -717,7 +735,7 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { // Not a go.string, generate a normal load fallthrough - case ssa.OpPPC64MOVWload, ssa.OpPPC64MOVHload, ssa.OpPPC64MOVWZload, ssa.OpPPC64MOVBZload, ssa.OpPPC64MOVHZload: + case ssa.OpPPC64MOVWload, ssa.OpPPC64MOVHload, ssa.OpPPC64MOVWZload, ssa.OpPPC64MOVBZload, ssa.OpPPC64MOVHZload, ssa.OpPPC64FMOVDload, ssa.OpPPC64FMOVSload: p := s.Prog(v.Op.Asm()) p.From.Type = obj.TYPE_MEM p.From.Reg = v.Args[0].Reg() @@ -739,10 +757,13 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.From.Type = obj.TYPE_REG p.From.Reg = v.Args[1].Reg() - case ssa.OpPPC64FMOVDload, ssa.OpPPC64FMOVSload: + case ssa.OpPPC64MOVDloadidx, ssa.OpPPC64MOVWloadidx, ssa.OpPPC64MOVHloadidx, ssa.OpPPC64MOVWZloadidx, + ssa.OpPPC64MOVBZloadidx, ssa.OpPPC64MOVHZloadidx, ssa.OpPPC64FMOVDloadidx, ssa.OpPPC64FMOVSloadidx, + ssa.OpPPC64MOVDBRloadidx, ssa.OpPPC64MOVWBRloadidx, ssa.OpPPC64MOVHBRloadidx: p := s.Prog(v.Op.Asm()) p.From.Type = obj.TYPE_MEM p.From.Reg = v.Args[0].Reg() + p.From.Index = v.Args[1].Reg() gc.AddAux(&p.From, v) p.To.Type = obj.TYPE_REG p.To.Reg = v.Reg() @@ -755,17 +776,21 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.To.Reg = v.Args[0].Reg() gc.AddAux(&p.To, v) - case ssa.OpPPC64MOVDstore, ssa.OpPPC64MOVWstore, ssa.OpPPC64MOVHstore, ssa.OpPPC64MOVBstore: + case ssa.OpPPC64MOVDstore, ssa.OpPPC64MOVWstore, ssa.OpPPC64MOVHstore, ssa.OpPPC64MOVBstore, ssa.OpPPC64FMOVDstore, ssa.OpPPC64FMOVSstore: p := s.Prog(v.Op.Asm()) p.From.Type = obj.TYPE_REG p.From.Reg = v.Args[1].Reg() p.To.Type = obj.TYPE_MEM p.To.Reg = v.Args[0].Reg() gc.AddAux(&p.To, v) - case ssa.OpPPC64FMOVDstore, ssa.OpPPC64FMOVSstore: + + case ssa.OpPPC64MOVDstoreidx, ssa.OpPPC64MOVWstoreidx, ssa.OpPPC64MOVHstoreidx, ssa.OpPPC64MOVBstoreidx, + ssa.OpPPC64FMOVDstoreidx, ssa.OpPPC64FMOVSstoreidx, ssa.OpPPC64MOVDBRstoreidx, ssa.OpPPC64MOVWBRstoreidx, + ssa.OpPPC64MOVHBRstoreidx: p := s.Prog(v.Op.Asm()) p.From.Type = obj.TYPE_REG - p.From.Reg = v.Args[1].Reg() + p.From.Reg = v.Args[2].Reg() + p.To.Index = v.Args[1].Reg() p.To.Type = obj.TYPE_MEM p.To.Reg = v.Args[0].Reg() gc.AddAux(&p.To, v) diff --git a/src/cmd/compile/internal/ssa/gen/386.rules b/src/cmd/compile/internal/ssa/gen/386.rules index 8131f1117a..f6aa37e884 100644 --- a/src/cmd/compile/internal/ssa/gen/386.rules +++ b/src/cmd/compile/internal/ssa/gen/386.rules @@ -44,8 +44,8 @@ (Xor(32|16|8) x y) -> (XORL x y) (Neg(32|16|8) x) -> (NEGL x) -(Neg32F x) && !config.use387 -> (PXOR x (MOVSSconst <typ.Float32> [f2i(math.Copysign(0, -1))])) -(Neg64F x) && !config.use387 -> (PXOR x (MOVSDconst <typ.Float64> [f2i(math.Copysign(0, -1))])) +(Neg32F x) && !config.use387 -> (PXOR x (MOVSSconst <typ.Float32> [auxFrom32F(float32(math.Copysign(0, -1)))])) +(Neg64F x) && !config.use387 -> (PXOR x (MOVSDconst <typ.Float64> [auxFrom64F(math.Copysign(0, -1))])) (Neg32F x) && config.use387 -> (FCHS x) (Neg64F x) && config.use387 -> (FCHS x) @@ -1116,10 +1116,10 @@ (XORL x x) -> (MOVLconst [0]) // checking AND against 0. -(CMP(L|W|B)const (ANDL x y) [0]) -> (TEST(L|W|B) x y) -(CMPLconst (ANDLconst [c] x) [0]) -> (TESTLconst [c] x) -(CMPWconst (ANDLconst [c] x) [0]) -> (TESTWconst [int64(int16(c))] x) -(CMPBconst (ANDLconst [c] x) [0]) -> (TESTBconst [int64(int8(c))] x) +(CMP(L|W|B)const l:(ANDL x y) [0]) && l.Uses==1 -> (TEST(L|W|B) x y) +(CMPLconst l:(ANDLconst [c] x) [0]) && l.Uses==1 -> (TESTLconst [c] x) +(CMPWconst l:(ANDLconst [c] x) [0]) && l.Uses==1 -> (TESTWconst [int64(int16(c))] x) +(CMPBconst l:(ANDLconst [c] x) [0]) && l.Uses==1 -> (TESTBconst [int64(int8(c))] x) // TEST %reg,%reg is shorter than CMP (CMP(L|W|B)const x [0]) -> (TEST(L|W|B) x x) diff --git a/src/cmd/compile/internal/ssa/gen/AMD64.rules b/src/cmd/compile/internal/ssa/gen/AMD64.rules index 4c11f8d036..f9ac5e4dce 100644 --- a/src/cmd/compile/internal/ssa/gen/AMD64.rules +++ b/src/cmd/compile/internal/ssa/gen/AMD64.rules @@ -41,8 +41,8 @@ (Com(64|32|16|8) x) -> (NOT(Q|L|L|L) x) (Neg(64|32|16|8) x) -> (NEG(Q|L|L|L) x) -(Neg32F x) -> (PXOR x (MOVSSconst <typ.Float32> [f2i(math.Copysign(0, -1))])) -(Neg64F x) -> (PXOR x (MOVSDconst <typ.Float64> [f2i(math.Copysign(0, -1))])) +(Neg32F x) -> (PXOR x (MOVSSconst <typ.Float32> [auxFrom32F(float32(math.Copysign(0, -1)))])) +(Neg64F x) -> (PXOR x (MOVSDconst <typ.Float64> [auxFrom64F(math.Copysign(0, -1))])) // Lowering boolean ops (AndB x y) -> (ANDL x y) @@ -709,7 +709,17 @@ (ANDL x (MOVLconst [c])) -> (ANDLconst [c] x) (AND(L|Q)const [c] (AND(L|Q)const [d] x)) -> (AND(L|Q)const [c & d] x) +(BTR(L|Q)const [c] (AND(L|Q)const [d] x)) -> (AND(L|Q)const [d &^ (1<<uint32(c))] x) +(AND(L|Q)const [c] (BTR(L|Q)const [d] x)) -> (AND(L|Q)const [c &^ (1<<uint32(d))] x) +(BTR(L|Q)const [c] (BTR(L|Q)const [d] x)) -> (AND(L|Q)const [^(1<<uint32(c) | 1<<uint32(d))] x) (XOR(L|Q)const [c] (XOR(L|Q)const [d] x)) -> (XOR(L|Q)const [c ^ d] x) +(BTC(L|Q)const [c] (XOR(L|Q)const [d] x)) -> (XOR(L|Q)const [d ^ 1<<uint32(c)] x) +(XOR(L|Q)const [c] (BTC(L|Q)const [d] x)) -> (XOR(L|Q)const [c ^ 1<<uint32(d)] x) +(BTC(L|Q)const [c] (BTC(L|Q)const [d] x)) -> (XOR(L|Q)const [1<<uint32(c) ^ 1<<uint32(d)] x) +(OR(L|Q)const [c] (OR(L|Q)const [d] x)) -> (OR(L|Q)const [c | d] x) +(OR(L|Q)const [c] (BTS(L|Q)const [d] x)) -> (OR(L|Q)const [c | 1<<uint32(d)] x) +(BTS(L|Q)const [c] (OR(L|Q)const [d] x)) -> (OR(L|Q)const [d | 1<<uint32(c)] x) +(BTS(L|Q)const [c] (BTS(L|Q)const [d] x)) -> (OR(L|Q)const [1<<uint32(d) | 1<<uint32(c)] x) (MULLconst [c] (MULLconst [d] x)) -> (MULLconst [int64(int32(c * d))] x) (MULQconst [c] (MULQconst [d] x)) && is32Bit(c*d) -> (MULQconst [c * d] x) @@ -1042,18 +1052,23 @@ ((ADD|SUB|AND|OR|XOR)Qload [off1+off2] {sym} val base mem) ((ADD|SUB|AND|OR|XOR)Lload [off1] {sym} val (ADDQconst [off2] base) mem) && is32Bit(off1+off2) -> ((ADD|SUB|AND|OR|XOR)Lload [off1+off2] {sym} val base mem) +(CMP(Q|L|W|B)load [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(off1+off2) -> + (CMP(Q|L|W|B)load [off1+off2] {sym} base val mem) +(CMP(Q|L|W|B)constload [valoff1] {sym} (ADDQconst [off2] base) mem) && ValAndOff(valoff1).canAdd(off2) -> + (CMP(Q|L|W|B)constload [ValAndOff(valoff1).add(off2)] {sym} base mem) + ((ADD|SUB|MUL|DIV)SSload [off1] {sym} val (ADDQconst [off2] base) mem) && is32Bit(off1+off2) -> ((ADD|SUB|MUL|DIV)SSload [off1+off2] {sym} val base mem) ((ADD|SUB|MUL|DIV)SDload [off1] {sym} val (ADDQconst [off2] base) mem) && is32Bit(off1+off2) -> ((ADD|SUB|MUL|DIV)SDload [off1+off2] {sym} val base mem) -((ADD|AND|OR|XOR)Qconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) && ValAndOff(valoff1).canAdd(off2) -> - ((ADD|AND|OR|XOR)Qconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) -((ADD|AND|OR|XOR)Lconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) && ValAndOff(valoff1).canAdd(off2) -> - ((ADD|AND|OR|XOR)Lconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) -((ADD|SUB|AND|OR|XOR)Qmodify [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(off1+off2) -> - ((ADD|SUB|AND|OR|XOR)Qmodify [off1+off2] {sym} base val mem) -((ADD|SUB|AND|OR|XOR)Lmodify [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(off1+off2) -> - ((ADD|SUB|AND|OR|XOR)Lmodify [off1+off2] {sym} base val mem) +((ADD|AND|OR|XOR|BTC|BTR|BTS)Qconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) && ValAndOff(valoff1).canAdd(off2) -> + ((ADD|AND|OR|XOR|BTC|BTR|BTS)Qconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) +((ADD|AND|OR|XOR|BTC|BTR|BTS)Lconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) && ValAndOff(valoff1).canAdd(off2) -> + ((ADD|AND|OR|XOR|BTC|BTR|BTS)Lconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) +((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Qmodify [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(off1+off2) -> + ((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Qmodify [off1+off2] {sym} base val mem) +((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Lmodify [off1] {sym} (ADDQconst [off2] base) val mem) && is32Bit(off1+off2) -> + ((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Lmodify [off1+off2] {sym} base val mem) // Fold constants into stores. (MOVQstore [off] {sym} ptr (MOVQconst [c]) mem) && validValAndOff(c,off) -> @@ -1088,24 +1103,31 @@ ((ADD|SUB|AND|OR|XOR)Lload [off1] {sym1} val (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) -> ((ADD|SUB|AND|OR|XOR)Lload [off1+off2] {mergeSym(sym1,sym2)} val base mem) +(CMP(Q|L|W|B)load [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + && is32Bit(off1+off2) && canMergeSym(sym1, sym2) -> + (CMP(Q|L|W|B)load [off1+off2] {mergeSym(sym1,sym2)} base val mem) +(CMP(Q|L|W|B)constload [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + && ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) -> + (CMP(Q|L|W|B)constload [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + ((ADD|SUB|MUL|DIV)SSload [off1] {sym1} val (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) -> ((ADD|SUB|MUL|DIV)SSload [off1+off2] {mergeSym(sym1,sym2)} val base mem) ((ADD|SUB|MUL|DIV)SDload [off1] {sym1} val (LEAQ [off2] {sym2} base) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) -> ((ADD|SUB|MUL|DIV)SDload [off1+off2] {mergeSym(sym1,sym2)} val base mem) -((ADD|AND|OR|XOR)Qconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) +((ADD|AND|OR|XOR|BTC|BTR|BTS)Qconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) && ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) -> - ((ADD|AND|OR|XOR)Qconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) -((ADD|AND|OR|XOR)Lconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + ((ADD|AND|OR|XOR|BTC|BTR|BTS)Qconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) +((ADD|AND|OR|XOR|BTC|BTR|BTS)Lconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) && ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) -> - ((ADD|AND|OR|XOR)Lconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) -((ADD|SUB|AND|OR|XOR)Qmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + ((ADD|AND|OR|XOR|BTC|BTR|BTS)Lconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) +((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Qmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) -> - ((ADD|SUB|AND|OR|XOR)Qmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) -((ADD|SUB|AND|OR|XOR)Lmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + ((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Qmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) +((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Lmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) -> - ((ADD|SUB|AND|OR|XOR)Lmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) + ((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Lmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) // generating indexed loads and stores (MOV(B|W|L|Q|SS|SD)load [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) -> @@ -1412,6 +1434,12 @@ (XORLconst [c] (MOVLconst [d])) -> (MOVLconst [c^d]) (NOTQ (MOVQconst [c])) -> (MOVQconst [^c]) (NOTL (MOVLconst [c])) -> (MOVLconst [^c]) +(BTSQconst [c] (MOVQconst [d])) -> (MOVQconst [d|(1<<uint32(c))]) +(BTSLconst [c] (MOVLconst [d])) -> (MOVLconst [d|(1<<uint32(c))]) +(BTRQconst [c] (MOVQconst [d])) -> (MOVQconst [d&^(1<<uint32(c))]) +(BTRLconst [c] (MOVLconst [d])) -> (MOVLconst [d&^(1<<uint32(c))]) +(BTCQconst [c] (MOVQconst [d])) -> (MOVQconst [d^(1<<uint32(c))]) +(BTCLconst [c] (MOVLconst [d])) -> (MOVLconst [d^(1<<uint32(c))]) // generic simplifications // TODO: more of this @@ -2292,11 +2320,11 @@ ((ADD|SUB|MUL|DIV)SD x l:(MOVSDload [off] {sym} ptr mem)) && canMergeLoad(v, l, x) && clobber(l) -> ((ADD|SUB|MUL|DIV)SDload x [off] {sym} ptr mem) ((ADD|SUB|MUL|DIV)SS x l:(MOVSSload [off] {sym} ptr mem)) && canMergeLoad(v, l, x) && clobber(l) -> ((ADD|SUB|MUL|DIV)SSload x [off] {sym} ptr mem) (MOVLstore {sym} [off] ptr y:((ADD|AND|OR|XOR)Lload x [off] {sym} ptr mem) mem) && y.Uses==1 && clobber(y) -> ((ADD|AND|OR|XOR)Lmodify [off] {sym} ptr x mem) -(MOVLstore {sym} [off] ptr y:((ADD|SUB|AND|OR|XOR)L l:(MOVLload [off] {sym} ptr mem) x) mem) && y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) -> - ((ADD|SUB|AND|OR|XOR)Lmodify [off] {sym} ptr x mem) +(MOVLstore {sym} [off] ptr y:((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)L l:(MOVLload [off] {sym} ptr mem) x) mem) && y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) -> + ((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Lmodify [off] {sym} ptr x mem) (MOVQstore {sym} [off] ptr y:((ADD|AND|OR|XOR)Qload x [off] {sym} ptr mem) mem) && y.Uses==1 && clobber(y) -> ((ADD|AND|OR|XOR)Qmodify [off] {sym} ptr x mem) -(MOVQstore {sym} [off] ptr y:((ADD|SUB|AND|OR|XOR)Q l:(MOVQload [off] {sym} ptr mem) x) mem) && y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) -> - ((ADD|SUB|AND|OR|XOR)Qmodify [off] {sym} ptr x mem) +(MOVQstore {sym} [off] ptr y:((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Q l:(MOVQload [off] {sym} ptr mem) x) mem) && y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) -> + ((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Qmodify [off] {sym} ptr x mem) // Merge ADDQconst and LEAQ into atomic loads. (MOVQatomicload [off1] {sym} (ADDQconst [off2] ptr) mem) && is32Bit(off1+off2) -> @@ -2380,12 +2408,12 @@ (MOVWQZX (MOVBQZX x)) -> (MOVBQZX x) (MOVBQZX (MOVBQZX x)) -> (MOVBQZX x) -(MOVQstore [off] {sym} ptr a:((ADD|AND|OR|XOR)Qconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) - && isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) -> - ((ADD|AND|OR|XOR)Qconstmodify {sym} [makeValAndOff(c,off)] ptr mem) -(MOVLstore [off] {sym} ptr a:((ADD|AND|OR|XOR)Lconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) - && isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) -> - ((ADD|AND|OR|XOR)Lconstmodify {sym} [makeValAndOff(c,off)] ptr mem) +(MOVQstore [off] {sym} ptr a:((ADD|AND|OR|XOR|BTC|BTR|BTS)Qconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) + && isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) -> + ((ADD|AND|OR|XOR|BTC|BTR|BTS)Qconstmodify {sym} [makeValAndOff(c,off)] ptr mem) +(MOVLstore [off] {sym} ptr a:((ADD|AND|OR|XOR|BTC|BTR|BTS)Lconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) + && isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) -> + ((ADD|AND|OR|XOR|BTC|BTR|BTS)Lconstmodify {sym} [makeValAndOff(c,off)] ptr mem) // float <-> int register moves, with no conversion. // These come up when compiling math.{Float{32,64}bits,Float{32,64}frombits}. diff --git a/src/cmd/compile/internal/ssa/gen/AMD64Ops.go b/src/cmd/compile/internal/ssa/gen/AMD64Ops.go index 512df99694..017c07071d 100644 --- a/src/cmd/compile/internal/ssa/gen/AMD64Ops.go +++ b/src/cmd/compile/internal/ssa/gen/AMD64Ops.go @@ -272,14 +272,14 @@ func init() { {name: "UCOMISS", argLength: 2, reg: fp2flags, asm: "UCOMISS", typ: "Flags"}, // arg0 compare to arg1, f32 {name: "UCOMISD", argLength: 2, reg: fp2flags, asm: "UCOMISD", typ: "Flags"}, // arg0 compare to arg1, f64 - {name: "BTL", argLength: 2, reg: gp2flags, asm: "BTL", typ: "Flags"}, // test whether bit arg0 % 32 in arg1 is set - {name: "BTQ", argLength: 2, reg: gp2flags, asm: "BTQ", typ: "Flags"}, // test whether bit arg0 % 64 in arg1 is set - {name: "BTCL", argLength: 2, reg: gp21, asm: "BTCL", resultInArg0: true, clobberFlags: true}, // complement bit arg0 % 32 in arg1 - {name: "BTCQ", argLength: 2, reg: gp21, asm: "BTCQ", resultInArg0: true, clobberFlags: true}, // complement bit arg0 % 64 in arg1 - {name: "BTRL", argLength: 2, reg: gp21, asm: "BTRL", resultInArg0: true, clobberFlags: true}, // reset bit arg0 % 32 in arg1 - {name: "BTRQ", argLength: 2, reg: gp21, asm: "BTRQ", resultInArg0: true, clobberFlags: true}, // reset bit arg0 % 64 in arg1 - {name: "BTSL", argLength: 2, reg: gp21, asm: "BTSL", resultInArg0: true, clobberFlags: true}, // set bit arg0 % 32 in arg1 - {name: "BTSQ", argLength: 2, reg: gp21, asm: "BTSQ", resultInArg0: true, clobberFlags: true}, // set bit arg0 % 64 in arg1 + {name: "BTL", argLength: 2, reg: gp2flags, asm: "BTL", typ: "Flags"}, // test whether bit arg0%32 in arg1 is set + {name: "BTQ", argLength: 2, reg: gp2flags, asm: "BTQ", typ: "Flags"}, // test whether bit arg0%64 in arg1 is set + {name: "BTCL", argLength: 2, reg: gp21, asm: "BTCL", resultInArg0: true, clobberFlags: true}, // complement bit arg1%32 in arg0 + {name: "BTCQ", argLength: 2, reg: gp21, asm: "BTCQ", resultInArg0: true, clobberFlags: true}, // complement bit arg1%64 in arg0 + {name: "BTRL", argLength: 2, reg: gp21, asm: "BTRL", resultInArg0: true, clobberFlags: true}, // reset bit arg1%32 in arg0 + {name: "BTRQ", argLength: 2, reg: gp21, asm: "BTRQ", resultInArg0: true, clobberFlags: true}, // reset bit arg1%64 in arg0 + {name: "BTSL", argLength: 2, reg: gp21, asm: "BTSL", resultInArg0: true, clobberFlags: true}, // set bit arg1%32 in arg0 + {name: "BTSQ", argLength: 2, reg: gp21, asm: "BTSQ", resultInArg0: true, clobberFlags: true}, // set bit arg1%64 in arg0 {name: "BTLconst", argLength: 1, reg: gp1flags, asm: "BTL", typ: "Flags", aux: "Int8"}, // test whether bit auxint in arg0 is set, 0 <= auxint < 32 {name: "BTQconst", argLength: 1, reg: gp1flags, asm: "BTQ", typ: "Flags", aux: "Int8"}, // test whether bit auxint in arg0 is set, 0 <= auxint < 64 {name: "BTCLconst", argLength: 1, reg: gp11, asm: "BTCL", resultInArg0: true, clobberFlags: true, aux: "Int8"}, // complement bit auxint in arg0, 0 <= auxint < 32 @@ -289,6 +289,20 @@ func init() { {name: "BTSLconst", argLength: 1, reg: gp11, asm: "BTSL", resultInArg0: true, clobberFlags: true, aux: "Int8"}, // set bit auxint in arg0, 0 <= auxint < 32 {name: "BTSQconst", argLength: 1, reg: gp11, asm: "BTSQ", resultInArg0: true, clobberFlags: true, aux: "Int8"}, // set bit auxint in arg0, 0 <= auxint < 64 + // direct bit operation on memory operand + {name: "BTCQmodify", argLength: 3, reg: gpstore, asm: "BTCQ", aux: "SymOff", typ: "Mem", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // complement bit arg1 in 64-bit arg0+auxint+aux, arg2=mem + {name: "BTCLmodify", argLength: 3, reg: gpstore, asm: "BTCL", aux: "SymOff", typ: "Mem", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // complement bit arg1 in 32-bit arg0+auxint+aux, arg2=mem + {name: "BTSQmodify", argLength: 3, reg: gpstore, asm: "BTSQ", aux: "SymOff", typ: "Mem", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // set bit arg1 in 64-bit arg0+auxint+aux, arg2=mem + {name: "BTSLmodify", argLength: 3, reg: gpstore, asm: "BTSL", aux: "SymOff", typ: "Mem", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // set bit arg1 in 32-bit arg0+auxint+aux, arg2=mem + {name: "BTRQmodify", argLength: 3, reg: gpstore, asm: "BTRQ", aux: "SymOff", typ: "Mem", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // reset bit arg1 in 64-bit arg0+auxint+aux, arg2=mem + {name: "BTRLmodify", argLength: 3, reg: gpstore, asm: "BTRL", aux: "SymOff", typ: "Mem", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // reset bit arg1 in 32-bit arg0+auxint+aux, arg2=mem + {name: "BTCQconstmodify", argLength: 2, reg: gpstoreconst, asm: "BTCQ", aux: "SymValAndOff", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // complement bit ValAndOff(AuxInt).Val() in 64-bit arg0+ValAndOff(AuxInt).Off()+aux, arg1=mem + {name: "BTCLconstmodify", argLength: 2, reg: gpstoreconst, asm: "BTCL", aux: "SymValAndOff", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // complement bit ValAndOff(AuxInt).Val() in 32-bit arg0+ValAndOff(AuxInt).Off()+aux, arg1=mem + {name: "BTSQconstmodify", argLength: 2, reg: gpstoreconst, asm: "BTSQ", aux: "SymValAndOff", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // set bit ValAndOff(AuxInt).Val() in 64-bit arg0+ValAndOff(AuxInt).Off()+aux, arg1=mem + {name: "BTSLconstmodify", argLength: 2, reg: gpstoreconst, asm: "BTSL", aux: "SymValAndOff", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // set bit ValAndOff(AuxInt).Val() in 32-bit arg0+ValAndOff(AuxInt).Off()+aux, arg1=mem + {name: "BTRQconstmodify", argLength: 2, reg: gpstoreconst, asm: "BTRQ", aux: "SymValAndOff", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // reset bit ValAndOff(AuxInt).Val() in 64-bit arg0+ValAndOff(AuxInt).Off()+aux, arg1=mem + {name: "BTRLconstmodify", argLength: 2, reg: gpstoreconst, asm: "BTRL", aux: "SymValAndOff", clobberFlags: true, faultOnNilArg0: true, symEffect: "Read,Write"}, // reset bit ValAndOff(AuxInt).Val() in 32-bit arg0+ValAndOff(AuxInt).Off()+aux, arg1=mem + {name: "TESTQ", argLength: 2, reg: gp2flags, commutative: true, asm: "TESTQ", typ: "Flags"}, // (arg0 & arg1) compare to 0 {name: "TESTL", argLength: 2, reg: gp2flags, commutative: true, asm: "TESTL", typ: "Flags"}, // (arg0 & arg1) compare to 0 {name: "TESTW", argLength: 2, reg: gp2flags, commutative: true, asm: "TESTW", typ: "Flags"}, // (arg0 & arg1) compare to 0 diff --git a/src/cmd/compile/internal/ssa/gen/ARM64.rules b/src/cmd/compile/internal/ssa/gen/ARM64.rules index ede7ed3d7a..659081ec8b 100644 --- a/src/cmd/compile/internal/ssa/gen/ARM64.rules +++ b/src/cmd/compile/internal/ssa/gen/ARM64.rules @@ -83,12 +83,18 @@ (Com8 x) -> (MVN x) // math package intrinsics +(Abs x) -> (FABSD x) (Sqrt x) -> (FSQRTD x) (Ceil x) -> (FRINTPD x) (Floor x) -> (FRINTMD x) (Round x) -> (FRINTAD x) +(RoundToEven x) -> (FRINTND x) (Trunc x) -> (FRINTZD x) +// lowering rotates +(RotateLeft32 x y) -> (RORW x (NEG <y.Type> y)) +(RotateLeft64 x y) -> (ROR x (NEG <y.Type> y)) + (Ctz64NonZero x) -> (Ctz64 x) (Ctz32NonZero x) -> (Ctz32 x) @@ -101,9 +107,20 @@ // Load args directly into the register class where it will be used. (FMOVDgpfp <t> (Arg [off] {sym})) -> @b.Func.Entry (Arg <t> [off] {sym}) +(FMOVDfpgp <t> (Arg [off] {sym})) -> @b.Func.Entry (Arg <t> [off] {sym}) + // Similarly for stores, if we see a store after FPR <-> GPR move, then redirect store to use the other register set. -(MOVDstore ptr (FMOVDfpgp val) mem) -> (FMOVDstore ptr val mem) -(FMOVDstore ptr (FMOVDgpfp val) mem) -> (MOVDstore ptr val mem) +(MOVDstore [off] {sym} ptr (FMOVDfpgp val) mem) -> (FMOVDstore [off] {sym} ptr val mem) +(FMOVDstore [off] {sym} ptr (FMOVDgpfp val) mem) -> (MOVDstore [off] {sym} ptr val mem) +(MOVWstore [off] {sym} ptr (FMOVSfpgp val) mem) -> (FMOVSstore [off] {sym} ptr val mem) +(FMOVSstore [off] {sym} ptr (FMOVSgpfp val) mem) -> (MOVWstore [off] {sym} ptr val mem) + +// float <-> int register moves, with no conversion. +// These come up when compiling math.{Float64bits, Float64frombits, Float32bits, Float32frombits}. +(MOVDload [off] {sym} ptr (FMOVDstore [off] {sym} ptr val _)) -> (FMOVDfpgp val) +(FMOVDload [off] {sym} ptr (MOVDstore [off] {sym} ptr val _)) -> (FMOVDgpfp val) +(MOVWUload [off] {sym} ptr (FMOVSstore [off] {sym} ptr val _)) -> (FMOVSfpgp val) +(FMOVSload [off] {sym} ptr (MOVWstore [off] {sym} ptr val _)) -> (FMOVSgpfp val) (BitLen64 x) -> (SUB (MOVDconst [64]) (CLZ <typ.Int> x)) @@ -125,6 +142,8 @@ // shifts // hardware instruction uses only the low 6 bits of the shift // we compare to 64 to ensure Go semantics for large shifts +// Rules about rotates with non-const shift are based on the following rules, +// if the following rules change, please also modify the rules based on them. (Lsh64x64 <t> x y) -> (CSEL {OpARM64LessThanU} (SLL <t> x y) (Const64 <t> [0]) (CMPconst [64] y)) (Lsh64x32 <t> x y) -> (CSEL {OpARM64LessThanU} (SLL <t> x (ZeroExt32to64 y)) (Const64 <t> [0]) (CMPconst [64] (ZeroExt32to64 y))) (Lsh64x16 <t> x y) -> (CSEL {OpARM64LessThanU} (SLL <t> x (ZeroExt16to64 y)) (Const64 <t> [0]) (CMPconst [64] (ZeroExt16to64 y))) @@ -1135,15 +1154,15 @@ (MULW (NEG x) y) -> (MNEGW x y) // madd/msub -(ADD a l:(MUL x y)) && l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) -> (MADD a x y) -(SUB a l:(MUL x y)) && l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) -> (MSUB a x y) -(ADD a l:(MNEG x y)) && l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) -> (MSUB a x y) -(SUB a l:(MNEG x y)) && l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) -> (MADD a x y) +(ADD a l:(MUL x y)) && l.Uses==1 && clobber(l) -> (MADD a x y) +(SUB a l:(MUL x y)) && l.Uses==1 && clobber(l) -> (MSUB a x y) +(ADD a l:(MNEG x y)) && l.Uses==1 && clobber(l) -> (MSUB a x y) +(SUB a l:(MNEG x y)) && l.Uses==1 && clobber(l) -> (MADD a x y) -(ADD a l:(MULW x y)) && l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) -> (MADDW a x y) -(SUB a l:(MULW x y)) && l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) -> (MSUBW a x y) -(ADD a l:(MNEGW x y)) && l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) -> (MSUBW a x y) -(SUB a l:(MNEGW x y)) && l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) -> (MADDW a x y) +(ADD a l:(MULW x y)) && a.Type.Size() != 8 && l.Uses==1 && clobber(l) -> (MADDW a x y) +(SUB a l:(MULW x y)) && a.Type.Size() != 8 && l.Uses==1 && clobber(l) -> (MSUBW a x y) +(ADD a l:(MNEGW x y)) && a.Type.Size() != 8 && l.Uses==1 && clobber(l) -> (MSUBW a x y) +(SUB a l:(MNEGW x y)) && a.Type.Size() != 8 && l.Uses==1 && clobber(l) -> (MADDW a x y) // mul by constant (MUL x (MOVDconst [-1])) -> (NEG x) @@ -1191,6 +1210,94 @@ (MNEGW x (MOVDconst [c])) && c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) -> (SLLconst <x.Type> [log2(c/7)] (SUBshiftLL <x.Type> x x [3])) (MNEGW x (MOVDconst [c])) && c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) -> (NEG (SLLconst <x.Type> [log2(c/9)] (ADDshiftLL <x.Type> x x [3]))) +(MADD a x (MOVDconst [-1])) -> (SUB a x) +(MADD a _ (MOVDconst [0])) -> a +(MADD a x (MOVDconst [1])) -> (ADD a x) +(MADD a x (MOVDconst [c])) && isPowerOfTwo(c) -> (ADDshiftLL a x [log2(c)]) +(MADD a x (MOVDconst [c])) && isPowerOfTwo(c-1) && c>=3 -> (ADD a (ADDshiftLL <x.Type> x x [log2(c-1)])) +(MADD a x (MOVDconst [c])) && isPowerOfTwo(c+1) && c>=7 -> (SUB a (SUBshiftLL <x.Type> x x [log2(c+1)])) +(MADD a x (MOVDconst [c])) && c%3 == 0 && isPowerOfTwo(c/3) -> (SUBshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) +(MADD a x (MOVDconst [c])) && c%5 == 0 && isPowerOfTwo(c/5) -> (ADDshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) +(MADD a x (MOVDconst [c])) && c%7 == 0 && isPowerOfTwo(c/7) -> (SUBshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) +(MADD a x (MOVDconst [c])) && c%9 == 0 && isPowerOfTwo(c/9) -> (ADDshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + +(MADD a (MOVDconst [-1]) x) -> (SUB a x) +(MADD a (MOVDconst [0]) _) -> a +(MADD a (MOVDconst [1]) x) -> (ADD a x) +(MADD a (MOVDconst [c]) x) && isPowerOfTwo(c) -> (ADDshiftLL a x [log2(c)]) +(MADD a (MOVDconst [c]) x) && isPowerOfTwo(c-1) && c>=3 -> (ADD a (ADDshiftLL <x.Type> x x [log2(c-1)])) +(MADD a (MOVDconst [c]) x) && isPowerOfTwo(c+1) && c>=7 -> (SUB a (SUBshiftLL <x.Type> x x [log2(c+1)])) +(MADD a (MOVDconst [c]) x) && c%3 == 0 && isPowerOfTwo(c/3) -> (SUBshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) +(MADD a (MOVDconst [c]) x) && c%5 == 0 && isPowerOfTwo(c/5) -> (ADDshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) +(MADD a (MOVDconst [c]) x) && c%7 == 0 && isPowerOfTwo(c/7) -> (SUBshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) +(MADD a (MOVDconst [c]) x) && c%9 == 0 && isPowerOfTwo(c/9) -> (ADDshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + +(MADDW a x (MOVDconst [c])) && int32(c)==-1 -> (SUB a x) +(MADDW a _ (MOVDconst [c])) && int32(c)==0 -> a +(MADDW a x (MOVDconst [c])) && int32(c)==1 -> (ADD a x) +(MADDW a x (MOVDconst [c])) && isPowerOfTwo(c) -> (ADDshiftLL a x [log2(c)]) +(MADDW a x (MOVDconst [c])) && isPowerOfTwo(c-1) && int32(c)>=3 -> (ADD a (ADDshiftLL <x.Type> x x [log2(c-1)])) +(MADDW a x (MOVDconst [c])) && isPowerOfTwo(c+1) && int32(c)>=7 -> (SUB a (SUBshiftLL <x.Type> x x [log2(c+1)])) +(MADDW a x (MOVDconst [c])) && c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c) -> (SUBshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) +(MADDW a x (MOVDconst [c])) && c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c) -> (ADDshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) +(MADDW a x (MOVDconst [c])) && c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) -> (SUBshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) +(MADDW a x (MOVDconst [c])) && c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) -> (ADDshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + +(MADDW a (MOVDconst [c]) x) && int32(c)==-1 -> (SUB a x) +(MADDW a (MOVDconst [c]) _) && int32(c)==0 -> a +(MADDW a (MOVDconst [c]) x) && int32(c)==1 -> (ADD a x) +(MADDW a (MOVDconst [c]) x) && isPowerOfTwo(c) -> (ADDshiftLL a x [log2(c)]) +(MADDW a (MOVDconst [c]) x) && isPowerOfTwo(c-1) && int32(c)>=3 -> (ADD a (ADDshiftLL <x.Type> x x [log2(c-1)])) +(MADDW a (MOVDconst [c]) x) && isPowerOfTwo(c+1) && int32(c)>=7 -> (SUB a (SUBshiftLL <x.Type> x x [log2(c+1)])) +(MADDW a (MOVDconst [c]) x) && c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c) -> (SUBshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) +(MADDW a (MOVDconst [c]) x) && c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c) -> (ADDshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) +(MADDW a (MOVDconst [c]) x) && c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) -> (SUBshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) +(MADDW a (MOVDconst [c]) x) && c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) -> (ADDshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + +(MSUB a x (MOVDconst [-1])) -> (ADD a x) +(MSUB a _ (MOVDconst [0])) -> a +(MSUB a x (MOVDconst [1])) -> (SUB a x) +(MSUB a x (MOVDconst [c])) && isPowerOfTwo(c) -> (SUBshiftLL a x [log2(c)]) +(MSUB a x (MOVDconst [c])) && isPowerOfTwo(c-1) && c>=3 -> (SUB a (ADDshiftLL <x.Type> x x [log2(c-1)])) +(MSUB a x (MOVDconst [c])) && isPowerOfTwo(c+1) && c>=7 -> (ADD a (SUBshiftLL <x.Type> x x [log2(c+1)])) +(MSUB a x (MOVDconst [c])) && c%3 == 0 && isPowerOfTwo(c/3) -> (ADDshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) +(MSUB a x (MOVDconst [c])) && c%5 == 0 && isPowerOfTwo(c/5) -> (SUBshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) +(MSUB a x (MOVDconst [c])) && c%7 == 0 && isPowerOfTwo(c/7) -> (ADDshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) +(MSUB a x (MOVDconst [c])) && c%9 == 0 && isPowerOfTwo(c/9) -> (SUBshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + +(MSUB a (MOVDconst [-1]) x) -> (ADD a x) +(MSUB a (MOVDconst [0]) _) -> a +(MSUB a (MOVDconst [1]) x) -> (SUB a x) +(MSUB a (MOVDconst [c]) x) && isPowerOfTwo(c) -> (SUBshiftLL a x [log2(c)]) +(MSUB a (MOVDconst [c]) x) && isPowerOfTwo(c-1) && c>=3 -> (SUB a (ADDshiftLL <x.Type> x x [log2(c-1)])) +(MSUB a (MOVDconst [c]) x) && isPowerOfTwo(c+1) && c>=7 -> (ADD a (SUBshiftLL <x.Type> x x [log2(c+1)])) +(MSUB a (MOVDconst [c]) x) && c%3 == 0 && isPowerOfTwo(c/3) -> (ADDshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) +(MSUB a (MOVDconst [c]) x) && c%5 == 0 && isPowerOfTwo(c/5) -> (SUBshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) +(MSUB a (MOVDconst [c]) x) && c%7 == 0 && isPowerOfTwo(c/7) -> (ADDshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) +(MSUB a (MOVDconst [c]) x) && c%9 == 0 && isPowerOfTwo(c/9) -> (SUBshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + +(MSUBW a x (MOVDconst [c])) && int32(c)==-1 -> (ADD a x) +(MSUBW a _ (MOVDconst [c])) && int32(c)==0 -> a +(MSUBW a x (MOVDconst [c])) && int32(c)==1 -> (SUB a x) +(MSUBW a x (MOVDconst [c])) && isPowerOfTwo(c) -> (SUBshiftLL a x [log2(c)]) +(MSUBW a x (MOVDconst [c])) && isPowerOfTwo(c-1) && int32(c)>=3 -> (SUB a (ADDshiftLL <x.Type> x x [log2(c-1)])) +(MSUBW a x (MOVDconst [c])) && isPowerOfTwo(c+1) && int32(c)>=7 -> (ADD a (SUBshiftLL <x.Type> x x [log2(c+1)])) +(MSUBW a x (MOVDconst [c])) && c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c) -> (ADDshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) +(MSUBW a x (MOVDconst [c])) && c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c) -> (SUBshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) +(MSUBW a x (MOVDconst [c])) && c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) -> (ADDshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) +(MSUBW a x (MOVDconst [c])) && c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) -> (SUBshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + +(MSUBW a (MOVDconst [c]) x) && int32(c)==-1 -> (ADD a x) +(MSUBW a (MOVDconst [c]) _) && int32(c)==0 -> a +(MSUBW a (MOVDconst [c]) x) && int32(c)==1 -> (SUB a x) +(MSUBW a (MOVDconst [c]) x) && isPowerOfTwo(c) -> (SUBshiftLL a x [log2(c)]) +(MSUBW a (MOVDconst [c]) x) && isPowerOfTwo(c-1) && int32(c)>=3 -> (SUB a (ADDshiftLL <x.Type> x x [log2(c-1)])) +(MSUBW a (MOVDconst [c]) x) && isPowerOfTwo(c+1) && int32(c)>=7 -> (ADD a (SUBshiftLL <x.Type> x x [log2(c+1)])) +(MSUBW a (MOVDconst [c]) x) && c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c) -> (ADDshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) +(MSUBW a (MOVDconst [c]) x) && c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c) -> (SUBshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) +(MSUBW a (MOVDconst [c]) x) && c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) -> (ADDshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) +(MSUBW a (MOVDconst [c]) x) && c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) -> (SUBshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + // div by constant (UDIV x (MOVDconst [1])) -> x (UDIV x (MOVDconst [c])) && isPowerOfTwo(c) -> (SRLconst [log2(c)] x) @@ -1242,6 +1349,14 @@ (MULW (MOVDconst [c]) (MOVDconst [d])) -> (MOVDconst [int64(int32(c)*int32(d))]) (MNEG (MOVDconst [c]) (MOVDconst [d])) -> (MOVDconst [-c*d]) (MNEGW (MOVDconst [c]) (MOVDconst [d])) -> (MOVDconst [-int64(int32(c)*int32(d))]) +(MADD (MOVDconst [c]) x y) -> (ADDconst [c] (MUL <x.Type> x y)) +(MADDW (MOVDconst [c]) x y) -> (ADDconst [c] (MULW <x.Type> x y)) +(MSUB (MOVDconst [c]) x y) -> (ADDconst [c] (MNEG <x.Type> x y)) +(MSUBW (MOVDconst [c]) x y) -> (ADDconst [c] (MNEGW <x.Type> x y)) +(MADD a (MOVDconst [c]) (MOVDconst [d])) -> (ADDconst [c*d] a) +(MADDW a (MOVDconst [c]) (MOVDconst [d])) -> (ADDconst [int64(int32(c)*int32(d))] a) +(MSUB a (MOVDconst [c]) (MOVDconst [d])) -> (SUBconst [c*d] a) +(MSUBW a (MOVDconst [c]) (MOVDconst [d])) -> (SUBconst [int64(int32(c)*int32(d))] a) (DIV (MOVDconst [c]) (MOVDconst [d])) -> (MOVDconst [c/d]) (UDIV (MOVDconst [c]) (MOVDconst [d])) -> (MOVDconst [int64(uint64(c)/uint64(d))]) (DIVW (MOVDconst [c]) (MOVDconst [d])) -> (MOVDconst [int64(int32(c)/int32(d))]) @@ -1490,6 +1605,12 @@ (CSEL0 {arm64Negate(bool.Op)} x flagArg(bool)) // absorb shifts into ops +(NEG x:(SLLconst [c] y)) && clobberIfDead(x) -> (NEGshiftLL [c] y) +(NEG x:(SRLconst [c] y)) && clobberIfDead(x) -> (NEGshiftRL [c] y) +(NEG x:(SRAconst [c] y)) && clobberIfDead(x) -> (NEGshiftRA [c] y) +(MVN x:(SLLconst [c] y)) && clobberIfDead(x) -> (MVNshiftLL [c] y) +(MVN x:(SRLconst [c] y)) && clobberIfDead(x) -> (MVNshiftRL [c] y) +(MVN x:(SRAconst [c] y)) && clobberIfDead(x) -> (MVNshiftRA [c] y) (ADD x0 x1:(SLLconst [c] y)) && clobberIfDead(x1) -> (ADDshiftLL x0 y [c]) (ADD x0 x1:(SRLconst [c] y)) && clobberIfDead(x1) -> (ADDshiftRL x0 y [c]) (ADD x0 x1:(SRAconst [c] y)) && clobberIfDead(x1) -> (ADDshiftRA x0 y [c]) @@ -1520,6 +1641,12 @@ (CMP x0:(SRLconst [c] y) x1) && clobberIfDead(x0) -> (InvertFlags (CMPshiftRL x1 y [c])) (CMP x0 x1:(SRAconst [c] y)) && clobberIfDead(x1) -> (CMPshiftRA x0 y [c]) (CMP x0:(SRAconst [c] y) x1) && clobberIfDead(x0) -> (InvertFlags (CMPshiftRA x1 y [c])) +(CMN x0 x1:(SLLconst [c] y)) && clobberIfDead(x1) -> (CMNshiftLL x0 y [c]) +(CMN x0 x1:(SRLconst [c] y)) && clobberIfDead(x1) -> (CMNshiftRL x0 y [c]) +(CMN x0 x1:(SRAconst [c] y)) && clobberIfDead(x1) -> (CMNshiftRA x0 y [c]) +(TST x0 x1:(SLLconst [c] y)) && clobberIfDead(x1) -> (TSTshiftLL x0 y [c]) +(TST x0 x1:(SRLconst [c] y)) && clobberIfDead(x1) -> (TSTshiftRL x0 y [c]) +(TST x0 x1:(SRAconst [c] y)) && clobberIfDead(x1) -> (TSTshiftRA x0 y [c]) // prefer *const ops to *shift ops (ADDshiftLL (MOVDconst [c]) x [d]) -> (ADDconst [c] (SLLconst <x.Type> x [d])) @@ -1537,8 +1664,20 @@ (CMPshiftLL (MOVDconst [c]) x [d]) -> (InvertFlags (CMPconst [c] (SLLconst <x.Type> x [d]))) (CMPshiftRL (MOVDconst [c]) x [d]) -> (InvertFlags (CMPconst [c] (SRLconst <x.Type> x [d]))) (CMPshiftRA (MOVDconst [c]) x [d]) -> (InvertFlags (CMPconst [c] (SRAconst <x.Type> x [d]))) +(CMNshiftLL (MOVDconst [c]) x [d]) -> (CMNconst [c] (SLLconst <x.Type> x [d])) +(CMNshiftRL (MOVDconst [c]) x [d]) -> (CMNconst [c] (SRLconst <x.Type> x [d])) +(CMNshiftRA (MOVDconst [c]) x [d]) -> (CMNconst [c] (SRAconst <x.Type> x [d])) +(TSTshiftLL (MOVDconst [c]) x [d]) -> (TSTconst [c] (SLLconst <x.Type> x [d])) +(TSTshiftRL (MOVDconst [c]) x [d]) -> (TSTconst [c] (SRLconst <x.Type> x [d])) +(TSTshiftRA (MOVDconst [c]) x [d]) -> (TSTconst [c] (SRAconst <x.Type> x [d])) // constant folding in *shift ops +(MVNshiftLL (MOVDconst [c]) [d]) -> (MOVDconst [^int64(uint64(c)<<uint64(d))]) +(MVNshiftRL (MOVDconst [c]) [d]) -> (MOVDconst [^int64(uint64(c)>>uint64(d))]) +(MVNshiftRA (MOVDconst [c]) [d]) -> (MOVDconst [^(c>>uint64(d))]) +(NEGshiftLL (MOVDconst [c]) [d]) -> (MOVDconst [-int64(uint64(c)<<uint64(d))]) +(NEGshiftRL (MOVDconst [c]) [d]) -> (MOVDconst [-int64(uint64(c)>>uint64(d))]) +(NEGshiftRA (MOVDconst [c]) [d]) -> (MOVDconst [-(c>>uint64(d))]) (ADDshiftLL x (MOVDconst [c]) [d]) -> (ADDconst x [int64(uint64(c)<<uint64(d))]) (ADDshiftRL x (MOVDconst [c]) [d]) -> (ADDconst x [int64(uint64(c)>>uint64(d))]) (ADDshiftRA x (MOVDconst [c]) [d]) -> (ADDconst x [c>>uint64(d)]) @@ -1566,6 +1705,12 @@ (CMPshiftLL x (MOVDconst [c]) [d]) -> (CMPconst x [int64(uint64(c)<<uint64(d))]) (CMPshiftRL x (MOVDconst [c]) [d]) -> (CMPconst x [int64(uint64(c)>>uint64(d))]) (CMPshiftRA x (MOVDconst [c]) [d]) -> (CMPconst x [c>>uint64(d)]) +(CMNshiftLL x (MOVDconst [c]) [d]) -> (CMNconst x [int64(uint64(c)<<uint64(d))]) +(CMNshiftRL x (MOVDconst [c]) [d]) -> (CMNconst x [int64(uint64(c)>>uint64(d))]) +(CMNshiftRA x (MOVDconst [c]) [d]) -> (CMNconst x [c>>uint64(d)]) +(TSTshiftLL x (MOVDconst [c]) [d]) -> (TSTconst x [int64(uint64(c)<<uint64(d))]) +(TSTshiftRL x (MOVDconst [c]) [d]) -> (TSTconst x [int64(uint64(c)>>uint64(d))]) +(TSTshiftRA x (MOVDconst [c]) [d]) -> (TSTconst x [c>>uint64(d)]) // simplification with *shift ops (SUBshiftLL x (SLLconst x [c]) [d]) && c==d -> (MOVDconst [0]) @@ -1590,7 +1735,7 @@ (ORNshiftRL x (SRLconst x [c]) [d]) && c==d -> (MOVDconst [-1]) (ORNshiftRA x (SRAconst x [c]) [d]) && c==d -> (MOVDconst [-1]) -// Generate rotates +// Generate rotates with const shift (ADDshiftLL [c] (SRLconst x [64-c]) x) -> (RORconst [64-c] x) ( ORshiftLL [c] (SRLconst x [64-c]) x) -> (RORconst [64-c] x) (XORshiftLL [c] (SRLconst x [64-c]) x) -> (RORconst [64-c] x) @@ -1608,6 +1753,38 @@ ( ORshiftRL <t> [c] (SLLconst x [32-c]) (MOVWUreg x)) && c < 32 && t.Size() == 4 -> (RORWconst [c] x) (XORshiftRL <t> [c] (SLLconst x [32-c]) (MOVWUreg x)) && c < 32 && t.Size() == 4 -> (RORWconst [c] x) +(RORconst [c] (RORconst [d] x)) -> (RORconst [(c+d)&63] x) +(RORWconst [c] (RORWconst [d] x)) -> (RORWconst [(c+d)&31] x) + +// Generate rotates with non-const shift. +// These rules match the Go source code like +// y &= 63 +// x << y | x >> (64-y) +// "|" can also be "^" or "+". +// As arm64 does not have a ROL instruction, so ROL(x, y) is replaced by ROR(x, -y). +((ADD|OR|XOR) (SLL x (ANDconst <t> [63] y)) + (CSEL0 <typ.UInt64> {cc} (SRL <typ.UInt64> x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) + (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))))) && cc.(Op) == OpARM64LessThanU + -> (ROR x (NEG <t> y)) +((ADD|OR|XOR) (SRL <typ.UInt64> x (ANDconst <t> [63] y)) + (CSEL0 <typ.UInt64> {cc} (SLL x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) + (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))))) && cc.(Op) == OpARM64LessThanU + -> (ROR x y) + +// These rules match the Go source code like +// y &= 31 +// x << y | x >> (32-y) +// "|" can also be "^" or "+". +// As arm64 does not have a ROLW instruction, so ROLW(x, y) is replaced by RORW(x, -y). +((ADD|OR|XOR) (SLL x (ANDconst <t> [31] y)) + (CSEL0 <typ.UInt32> {cc} (SRL <typ.UInt32> (MOVWUreg x) (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) + (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))))) && cc.(Op) == OpARM64LessThanU + -> (RORW x (NEG <t> y)) +((ADD|OR|XOR) (SRL <typ.UInt32> (MOVWUreg x) (ANDconst <t> [31] y)) + (CSEL0 <typ.UInt32> {cc} (SLL x (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) + (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))))) && cc.(Op) == OpARM64LessThanU + -> (RORW x y) + // Extract from reg pair (ADDshiftLL [c] (SRLconst x [64-c]) x2) -> (EXTRconst [64-c] x2 x) ( ORshiftLL [c] (SRLconst x [64-c]) x2) -> (EXTRconst [64-c] x2 x) @@ -1626,6 +1803,9 @@ (SRLconst [c] (SLLconst [c] x)) && 0 < c && c < 64 -> (ANDconst [1<<uint(64-c)-1] x) // mask out high bits (SLLconst [c] (SRLconst [c] x)) && 0 < c && c < 64 -> (ANDconst [^(1<<uint(c)-1)] x) // mask out low bits +// Special case setting bit as 1. An example is math.Copysign(c,-1) +(ORconst [c1] (ANDconst [c2] x)) && c2|c1 == ^0 -> (ORconst [c1] x) + // bitfield ops // sbfiz diff --git a/src/cmd/compile/internal/ssa/gen/ARM64Ops.go b/src/cmd/compile/internal/ssa/gen/ARM64Ops.go index eb0ad530a1..fc0a41527b 100644 --- a/src/cmd/compile/internal/ssa/gen/ARM64Ops.go +++ b/src/cmd/compile/internal/ssa/gen/ARM64Ops.go @@ -212,6 +212,7 @@ func init() { // unary ops {name: "MVN", argLength: 1, reg: gp11, asm: "MVN"}, // ^arg0 {name: "NEG", argLength: 1, reg: gp11, asm: "NEG"}, // -arg0 + {name: "FABSD", argLength: 1, reg: fp11, asm: "FABSD"}, // abs(arg0), float64 {name: "FNEGS", argLength: 1, reg: fp11, asm: "FNEGS"}, // -arg0, float32 {name: "FNEGD", argLength: 1, reg: fp11, asm: "FNEGD"}, // -arg0, float64 {name: "FSQRTD", argLength: 1, reg: fp11, asm: "FSQRTD"}, // sqrt(arg0), float64 @@ -248,6 +249,8 @@ func init() { {name: "SRLconst", argLength: 1, reg: gp11, asm: "LSR", aux: "Int64"}, // arg0 >> auxInt, unsigned {name: "SRA", argLength: 2, reg: gp21, asm: "ASR"}, // arg0 >> arg1, signed, shift amount is mod 64 {name: "SRAconst", argLength: 1, reg: gp11, asm: "ASR", aux: "Int64"}, // arg0 >> auxInt, signed + {name: "ROR", argLength: 2, reg: gp21, asm: "ROR"}, // arg0 right rotate by (arg1 mod 64) bits + {name: "RORW", argLength: 2, reg: gp21, asm: "RORW"}, // arg0 right rotate by (arg1 mod 32) bits {name: "RORconst", argLength: 1, reg: gp11, asm: "ROR", aux: "Int64"}, // arg0 right rotate by auxInt bits {name: "RORWconst", argLength: 1, reg: gp11, asm: "RORW", aux: "Int64"}, // uint32(arg0) right rotate by auxInt bits {name: "EXTRconst", argLength: 2, reg: gp21, asm: "EXTR", aux: "Int64"}, // extract 64 bits from arg0:arg1 starting at lsb auxInt @@ -270,6 +273,12 @@ func init() { {name: "FCMPD", argLength: 2, reg: fp2flags, asm: "FCMPD", typ: "Flags"}, // arg0 compare to arg1, float64 // shifted ops + {name: "MVNshiftLL", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"}, // ^(arg0<<auxInt) + {name: "MVNshiftRL", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"}, // ^(arg0>>auxInt), unsigned shift + {name: "MVNshiftRA", argLength: 1, reg: gp11, asm: "MVN", aux: "Int64"}, // ^(arg0>>auxInt), signed shift + {name: "NEGshiftLL", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"}, // -(arg0<<auxInt) + {name: "NEGshiftRL", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"}, // -(arg0>>auxInt), unsigned shift + {name: "NEGshiftRA", argLength: 1, reg: gp11, asm: "NEG", aux: "Int64"}, // -(arg0>>auxInt), signed shift {name: "ADDshiftLL", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"}, // arg0 + arg1<<auxInt {name: "ADDshiftRL", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"}, // arg0 + arg1>>auxInt, unsigned shift {name: "ADDshiftRA", argLength: 2, reg: gp21, asm: "ADD", aux: "Int64"}, // arg0 + arg1>>auxInt, signed shift @@ -297,6 +306,12 @@ func init() { {name: "CMPshiftLL", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1<<auxInt {name: "CMPshiftRL", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1>>auxInt, unsigned shift {name: "CMPshiftRA", argLength: 2, reg: gp2flags, asm: "CMP", aux: "Int64", typ: "Flags"}, // arg0 compare to arg1>>auxInt, signed shift + {name: "CMNshiftLL", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1<<auxInt) compare to 0 + {name: "CMNshiftRL", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1>>auxInt) compare to 0, unsigned shift + {name: "CMNshiftRA", argLength: 2, reg: gp2flags, asm: "CMN", aux: "Int64", typ: "Flags"}, // (arg0 + arg1>>auxInt) compare to 0, signed shift + {name: "TSTshiftLL", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1<<auxInt) compare to 0 + {name: "TSTshiftRL", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1>>auxInt) compare to 0, unsigned shift + {name: "TSTshiftRA", argLength: 2, reg: gp2flags, asm: "TST", aux: "Int64", typ: "Flags"}, // (arg0 & arg1>>auxInt) compare to 0, signed shift // bitfield ops // for all bitfield ops lsb is auxInt>>8, width is auxInt&0xff @@ -388,6 +403,8 @@ func init() { {name: "FMOVDgpfp", argLength: 1, reg: gpfp, asm: "FMOVD"}, // move int64 to float64 (no conversion) {name: "FMOVDfpgp", argLength: 1, reg: fpgp, asm: "FMOVD"}, // move float64 to int64 (no conversion) + {name: "FMOVSgpfp", argLength: 1, reg: gpfp, asm: "FMOVS"}, // move 32bits from int to float reg (no conversion) + {name: "FMOVSfpgp", argLength: 1, reg: fpgp, asm: "FMOVS"}, // move 32bits from float to int reg, zero extend (no conversion) // conversions {name: "MOVBreg", argLength: 1, reg: gp11, asm: "MOVB"}, // move from arg0, sign-extended from byte @@ -422,6 +439,7 @@ func init() { // floating-point round to integral {name: "FRINTAD", argLength: 1, reg: fp11, asm: "FRINTAD"}, {name: "FRINTMD", argLength: 1, reg: fp11, asm: "FRINTMD"}, + {name: "FRINTND", argLength: 1, reg: fp11, asm: "FRINTND"}, {name: "FRINTPD", argLength: 1, reg: fp11, asm: "FRINTPD"}, {name: "FRINTZD", argLength: 1, reg: fp11, asm: "FRINTZD"}, diff --git a/src/cmd/compile/internal/ssa/gen/PPC64.rules b/src/cmd/compile/internal/ssa/gen/PPC64.rules index 6ef8c7b5b9..7d79c9ad50 100644 --- a/src/cmd/compile/internal/ssa/gen/PPC64.rules +++ b/src/cmd/compile/internal/ssa/gen/PPC64.rules @@ -25,6 +25,7 @@ (Mul64 x y) -> (MULLD x y) (Mul(32|16|8) x y) -> (MULLW x y) +(Mul64uhilo x y) -> (LoweredMuluhilo x y) (Div64 x y) -> (DIVD x y) (Div64u x y) -> (DIVDU x y) @@ -74,11 +75,11 @@ (ConstBool [b]) -> (MOVDconst [b]) // Constant folding -(FABS (FMOVDconst [x])) -> (FMOVDconst [f2i(math.Abs(i2f(x)))]) -(FSQRT (FMOVDconst [x])) -> (FMOVDconst [f2i(math.Sqrt(i2f(x)))]) -(FFLOOR (FMOVDconst [x])) -> (FMOVDconst [f2i(math.Floor(i2f(x)))]) -(FCEIL (FMOVDconst [x])) -> (FMOVDconst [f2i(math.Ceil(i2f(x)))]) -(FTRUNC (FMOVDconst [x])) -> (FMOVDconst [f2i(math.Trunc(i2f(x)))]) +(FABS (FMOVDconst [x])) -> (FMOVDconst [auxFrom64F(math.Abs(auxTo64F(x)))]) +(FSQRT (FMOVDconst [x])) -> (FMOVDconst [auxFrom64F(math.Sqrt(auxTo64F(x)))]) +(FFLOOR (FMOVDconst [x])) -> (FMOVDconst [auxFrom64F(math.Floor(auxTo64F(x)))]) +(FCEIL (FMOVDconst [x])) -> (FMOVDconst [auxFrom64F(math.Ceil(auxTo64F(x)))]) +(FTRUNC (FMOVDconst [x])) -> (FMOVDconst [auxFrom64F(math.Trunc(auxTo64F(x)))]) // Rotate generation with const shift (ADD (SLDconst x [c]) (SRDconst x [d])) && d == 64-c -> (ROTLconst [c] x) @@ -168,6 +169,20 @@ (Rsh8x32 x (MOVDconst [c])) && uint32(c) < 8 -> (SRAWconst (SignExt8to32 x) [c]) (Rsh8Ux32 x (MOVDconst [c])) && uint32(c) < 8 -> (SRWconst (ZeroExt8to32 x) [c]) +// Lower bounded shifts first. No need to check shift value. +(Lsh64x(64|32|16|8) x y) && shiftIsBounded(v) -> (SLD x y) +(Lsh32x(64|32|16|8) x y) && shiftIsBounded(v) -> (SLW x y) +(Lsh16x(64|32|16|8) x y) && shiftIsBounded(v) -> (SLW x y) +(Lsh8x(64|32|16|8) x y) && shiftIsBounded(v) -> (SLW x y) +(Rsh64Ux(64|32|16|8) x y) && shiftIsBounded(v) -> (SRD x y) +(Rsh32Ux(64|32|16|8) x y) && shiftIsBounded(v) -> (SRW x y) +(Rsh16Ux(64|32|16|8) x y) && shiftIsBounded(v) -> (SRW (MOVHZreg x) y) +(Rsh8Ux(64|32|16|8) x y) && shiftIsBounded(v) -> (SRW (MOVBZreg x) y) +(Rsh64x(64|32|16|8) x y) && shiftIsBounded(v) -> (SRAD x y) +(Rsh32x(64|32|16|8) x y) && shiftIsBounded(v) -> (SRAW x y) +(Rsh16x(64|32|16|8) x y) && shiftIsBounded(v) -> (SRAW (MOVHreg x) y) +(Rsh8x(64|32|16|8) x y) && shiftIsBounded(v) -> (SRAW (MOVBreg x) y) + // non-constant rotates // These are subexpressions found in statements that can become rotates // In these cases the shift count is known to be < 64 so the more complicated expressions @@ -660,14 +675,51 @@ (MOVWreg y:(AND (MOVDconst [c]) _)) && uint64(c) <= 0x7FFFFFFF -> y // small and of zero-extend -> either zero-extend or small and - // degenerate-and (ANDconst [c] y:(MOVBZreg _)) && c&0xFF == 0xFF -> y +(ANDconst [0xFF] y:(MOVBreg _)) -> y (ANDconst [c] y:(MOVHZreg _)) && c&0xFFFF == 0xFFFF -> y -(ANDconst [c] y:(MOVWZreg _)) && c&0xFFFFFFFF == 0xFFFFFFFF -> y - // normal case -(ANDconst [c] (MOVBZreg x)) -> (ANDconst [c&0xFF] x) -(ANDconst [c] (MOVHZreg x)) -> (ANDconst [c&0xFFFF] x) -(ANDconst [c] (MOVWZreg x)) -> (ANDconst [c&0xFFFFFFFF] x) +(ANDconst [0xFFFF] y:(MOVHreg _)) -> y + +(AND (MOVDconst [c]) y:(MOVWZreg _)) && c&0xFFFFFFFF == 0xFFFFFFFF -> y +(AND (MOVDconst [0xFFFFFFFF]) y:(MOVWreg x)) -> (MOVWZreg x) +// normal case +(ANDconst [c] (MOV(B|BZ)reg x)) -> (ANDconst [c&0xFF] x) +(ANDconst [c] (MOV(H|HZ)reg x)) -> (ANDconst [c&0xFFFF] x) +(ANDconst [c] (MOV(W|WZ)reg x)) -> (ANDconst [c&0xFFFFFFFF] x) + +// Eliminate unnecessary sign/zero extend following right shift +(MOV(B|H|W)Zreg (SRWconst [c] (MOVBZreg x))) -> (SRWconst [c] (MOVBZreg x)) +(MOV(H|W)Zreg (SRWconst [c] (MOVHZreg x))) -> (SRWconst [c] (MOVHZreg x)) +(MOVWZreg (SRWconst [c] (MOVWZreg x))) -> (SRWconst [c] (MOVWZreg x)) +(MOV(B|H|W)reg (SRAWconst [c] (MOVBreg x))) -> (SRAWconst [c] (MOVBreg x)) +(MOV(H|W)reg (SRAWconst [c] (MOVHreg x))) -> (SRAWconst [c] (MOVHreg x)) +(MOVWreg (SRAWconst [c] (MOVWreg x))) -> (SRAWconst [c] (MOVWreg x)) + +(MOVWZreg (SRWconst [c] x)) && sizeof(x.Type) <= 32 -> (SRWconst [c] x) +(MOVHZreg (SRWconst [c] x)) && sizeof(x.Type) <= 16 -> (SRWconst [c] x) +(MOVBZreg (SRWconst [c] x)) && sizeof(x.Type) == 8 -> (SRWconst [c] x) +(MOVWreg (SRAWconst [c] x)) && sizeof(x.Type) <= 32 -> (SRAWconst [c] x) +(MOVHreg (SRAWconst [c] x)) && sizeof(x.Type) <= 16 -> (SRAWconst [c] x) +(MOVBreg (SRAWconst [c] x)) && sizeof(x.Type) == 8 -> (SRAWconst [c] x) + +// initial right shift will handle sign/zero extend +(MOVBZreg (SRDconst [c] x)) && c>=56 -> (SRDconst [c] x) +(MOVBreg (SRDconst [c] x)) && c>56 -> (SRDconst [c] x) +(MOVBreg (SRDconst [c] x)) && c==56 -> (SRADconst [c] x) +(MOVBZreg (SRWconst [c] x)) && c>=24 -> (SRWconst [c] x) +(MOVBreg (SRWconst [c] x)) && c>24 -> (SRWconst [c] x) +(MOVBreg (SRWconst [c] x)) && c==24 -> (SRAWconst [c] x) + +(MOVHZreg (SRDconst [c] x)) && c>=48 -> (SRDconst [c] x) +(MOVHreg (SRDconst [c] x)) && c>48 -> (SRDconst [c] x) +(MOVHreg (SRDconst [c] x)) && c==48 -> (SRADconst [c] x) +(MOVHZreg (SRWconst [c] x)) && c>=16 -> (SRWconst [c] x) +(MOVHreg (SRWconst [c] x)) && c>16 -> (SRWconst [c] x) +(MOVHreg (SRWconst [c] x)) && c==16 -> (SRAWconst [c] x) + +(MOVWZreg (SRDconst [c] x)) && c>=32 -> (SRDconst [c] x) +(MOVWreg (SRDconst [c] x)) && c>32 -> (SRDconst [c] x) +(MOVWreg (SRDconst [c] x)) && c==32 -> (SRADconst [c] x) // Various redundant zero/sign extension combinations. (MOVBZreg y:(MOVBZreg _)) -> y // repeat @@ -796,11 +848,19 @@ (MOVHZload [off1] {sym} (ADDconst [off2] x) mem) && is16Bit(off1+off2) -> (MOVHZload [off1+off2] {sym} x mem) (MOVBZload [off1] {sym} (ADDconst [off2] x) mem) && is16Bit(off1+off2) -> (MOVBZload [off1+off2] {sym} x mem) +// Determine load + addressing that can be done as a register indexed load +(MOV(D|W|WZ|H|HZ|BZ)load [0] {sym} p:(ADD ptr idx) mem) && sym == nil && p.Uses == 1 -> (MOV(D|W|WZ|H|HZ|BZ)loadidx ptr idx mem) + +// Determine indexed loads with constant values that can be done without index +(MOV(D|W|WZ|H|HZ|BZ)loadidx ptr (MOVDconst [c]) mem) && is16Bit(c) -> (MOV(D|W|WZ|H|HZ|BZ)load [c] ptr mem) +(MOV(D|W|WZ|H|HZ|BZ)loadidx (MOVDconst [c]) ptr mem) && is16Bit(c) -> (MOV(D|W|WZ|H|HZ|BZ)load [c] ptr mem) + + // Store of zero -> storezero -(MOVDstore [off] {sym} ptr (MOVDconst [c]) mem) && c == 0 -> (MOVDstorezero [off] {sym} ptr mem) -(MOVWstore [off] {sym} ptr (MOVDconst [c]) mem) && c == 0 -> (MOVWstorezero [off] {sym} ptr mem) -(MOVHstore [off] {sym} ptr (MOVDconst [c]) mem) && c == 0 -> (MOVHstorezero [off] {sym} ptr mem) -(MOVBstore [off] {sym} ptr (MOVDconst [c]) mem) && c == 0 -> (MOVBstorezero [off] {sym} ptr mem) +(MOVDstore [off] {sym} ptr (MOVDconst [0]) mem) -> (MOVDstorezero [off] {sym} ptr mem) +(MOVWstore [off] {sym} ptr (MOVDconst [0]) mem) -> (MOVWstorezero [off] {sym} ptr mem) +(MOVHstore [off] {sym} ptr (MOVDconst [0]) mem) -> (MOVHstorezero [off] {sym} ptr mem) +(MOVBstore [off] {sym} ptr (MOVDconst [0]) mem) -> (MOVBstorezero [off] {sym} ptr mem) // Fold offsets for storezero (MOVDstorezero [off1] {sym} (ADDconst [off2] x) mem) && is16Bit(off1+off2) -> @@ -812,6 +872,13 @@ (MOVBstorezero [off1] {sym} (ADDconst [off2] x) mem) && is16Bit(off1+off2) -> (MOVBstorezero [off1+off2] {sym} x mem) +// Stores with addressing that can be done as indexed stores +(MOV(D|W|H|B)store [off] {sym} p:(ADD ptr idx) val mem) && off == 0 && sym == nil && p.Uses == 1 -> (MOV(D|W|H|B)storeidx ptr idx val mem) + +// Stores with constant index values can be done without indexed instructions +(MOV(D|W|H|B)storeidx ptr (MOVDconst [c]) val mem) && is16Bit(c) -> (MOV(D|W|H|B)store [c] ptr val mem) +(MOV(D|W|H|B)storeidx (MOVDconst [c]) ptr val mem) && is16Bit(c) -> (MOV(D|W|H|B)store [c] ptr val mem) + // Fold symbols into storezero (MOVDstorezero [off1] {sym1} p:(MOVDaddr [off2] {sym2} x) mem) && canMergeSym(sym1,sym2) && (x.Op != OpSB || p.Uses == 1) -> @@ -851,22 +918,43 @@ (ZeroExt16to(32|64) x) -> (MOVHZreg x) (ZeroExt32to64 x) -> (MOVWZreg x) -(Trunc(16|32|64)to8 x) -> (MOVBreg x) -(Trunc(32|64)to16 x) -> (MOVHreg x) -(Trunc64to32 x) -> (MOVWreg x) +(Trunc(16|32|64)to8 x) && isSigned(x.Type) -> (MOVBreg x) +(Trunc(16|32|64)to8 x) -> (MOVBZreg x) +(Trunc(32|64)to16 x) && isSigned(x.Type) -> (MOVHreg x) +(Trunc(32|64)to16 x) -> (MOVHZreg x) +(Trunc64to32 x) && isSigned(x.Type) -> (MOVWreg x) +(Trunc64to32 x) -> (MOVWZreg x) (Slicemask <t> x) -> (SRADconst (NEG <t> x) [63]) // Note that MOV??reg returns a 64-bit int, x is not necessarily that wide // This may interact with other patterns in the future. (Compare with arm64) -(MOVBZreg x:(MOVBZload _ _)) -> x -(MOVHZreg x:(MOVHZload _ _)) -> x -(MOVHreg x:(MOVHload _ _)) -> x +(MOV(B|H|W)Zreg x:(MOVBZload _ _)) -> x +(MOV(B|H|W)Zreg x:(MOVBZloadidx _ _ _)) -> x +(MOV(H|W)Zreg x:(MOVHZload _ _)) -> x +(MOV(H|W)Zreg x:(MOVHZloadidx _ _ _)) -> x +(MOV(H|W)reg x:(MOVHload _ _)) -> x +(MOV(H|W)reg x:(MOVHloadidx _ _ _)) -> x +(MOVWZreg x:(MOVWZload _ _)) -> x +(MOVWZreg x:(MOVWZloadidx _ _ _)) -> x +(MOVWreg x:(MOVWload _ _)) -> x +(MOVWreg x:(MOVWloadidx _ _ _)) -> x + +// don't extend if argument is already extended +(MOVBreg x:(Arg <t>)) && is8BitInt(t) && isSigned(t) -> x +(MOVBZreg x:(Arg <t>)) && is8BitInt(t) && !isSigned(t) -> x +(MOVHreg x:(Arg <t>)) && (is8BitInt(t) || is16BitInt(t)) && isSigned(t) -> x +(MOVHZreg x:(Arg <t>)) && (is8BitInt(t) || is16BitInt(t)) && !isSigned(t) -> x +(MOVWreg x:(Arg <t>)) && (is8BitInt(t) || is16BitInt(t) || is32BitInt(t)) && isSigned(t) -> x +(MOVWZreg x:(Arg <t>)) && (is8BitInt(t) || is16BitInt(t) || is32BitInt(t)) && !isSigned(t) -> x (MOVBZreg (MOVDconst [c])) -> (MOVDconst [int64(uint8(c))]) (MOVBreg (MOVDconst [c])) -> (MOVDconst [int64(int8(c))]) (MOVHZreg (MOVDconst [c])) -> (MOVDconst [int64(uint16(c))]) (MOVHreg (MOVDconst [c])) -> (MOVDconst [int64(int16(c))]) +(MOVWreg (MOVDconst [c])) -> (MOVDconst [int64(int32(c))]) +(MOVWZreg (MOVDconst [c])) -> (MOVDconst [int64(uint32(c))]) + // Lose widening ops fed to to stores (MOVBstore [off] {sym} ptr (MOV(B|BZ|H|HZ|W|WZ)reg x) mem) -> (MOVBstore [off] {sym} ptr x mem) @@ -874,6 +962,11 @@ (MOVWstore [off] {sym} ptr (MOV(W|WZ)reg x) mem) -> (MOVWstore [off] {sym} ptr x mem) (MOVBstore [off] {sym} ptr (SRWconst (MOV(H|HZ)reg x) [c]) mem) && c <= 8 -> (MOVBstore [off] {sym} ptr (SRWconst <typ.UInt32> x [c]) mem) (MOVBstore [off] {sym} ptr (SRWconst (MOV(W|WZ)reg x) [c]) mem) && c <= 24 -> (MOVBstore [off] {sym} ptr (SRWconst <typ.UInt32> x [c]) mem) +(MOVBstoreidx [off] {sym} ptr idx (MOV(B|BZ|H|HZ|W|WZ)reg x) mem) -> (MOVBstoreidx [off] {sym} ptr idx x mem) +(MOVHstoreidx [off] {sym} ptr idx (MOV(H|HZ|W|WZ)reg x) mem) -> (MOVHstoreidx [off] {sym} ptr idx x mem) +(MOVWstoreidx [off] {sym} ptr idx (MOV(W|WZ)reg x) mem) -> (MOVWstoreidx [off] {sym} ptr idx x mem) +(MOVBstoreidx [off] {sym} ptr idx (SRWconst (MOV(H|HZ)reg x) [c]) mem) && c <= 8 -> (MOVBstoreidx [off] {sym} ptr idx (SRWconst <typ.UInt32> x [c]) mem) +(MOVBstoreidx [off] {sym} ptr idx (SRWconst (MOV(W|WZ)reg x) [c]) mem) && c <= 24 -> (MOVBstoreidx [off] {sym} ptr idx (SRWconst <typ.UInt32> x [c]) mem) (MOVHBRstore {sym} ptr (MOV(H|HZ|W|WZ)reg x) mem) -> (MOVHBRstore {sym} ptr x mem) (MOVWBRstore {sym} ptr (MOV(W|WZ)reg x) mem) -> (MOVWBRstore {sym} ptr x mem) diff --git a/src/cmd/compile/internal/ssa/gen/PPC64Ops.go b/src/cmd/compile/internal/ssa/gen/PPC64Ops.go index ce5d552375..c82f7312fe 100644 --- a/src/cmd/compile/internal/ssa/gen/PPC64Ops.go +++ b/src/cmd/compile/internal/ssa/gen/PPC64Ops.go @@ -135,11 +135,14 @@ func init() { gp01 = regInfo{inputs: nil, outputs: []regMask{gp}} gp11 = regInfo{inputs: []regMask{gp | sp | sb}, outputs: []regMask{gp}} gp21 = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb}, outputs: []regMask{gp}} + gp22 = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb}, outputs: []regMask{gp, gp}} gp1cr = regInfo{inputs: []regMask{gp | sp | sb}} gp2cr = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb}} crgp = regInfo{inputs: nil, outputs: []regMask{gp}} gpload = regInfo{inputs: []regMask{gp | sp | sb}, outputs: []regMask{gp}} + gploadidx = regInfo{inputs: []regMask{gp | sp | sb, gp}, outputs: []regMask{gp}} gpstore = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb}} + gpstoreidx = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb, gp | sp | sb}} gpstorezero = regInfo{inputs: []regMask{gp | sp | sb}} // ppc64.REGZERO is reserved zero value gpxchg = regInfo{inputs: []regMask{gp | sp | sb, gp}, outputs: []regMask{gp}} gpcas = regInfo{inputs: []regMask{gp | sp | sb, gp, gp}, outputs: []regMask{gp}} @@ -151,7 +154,9 @@ func init() { fp31 = regInfo{inputs: []regMask{fp, fp, fp}, outputs: []regMask{fp}} fp2cr = regInfo{inputs: []regMask{fp, fp}} fpload = regInfo{inputs: []regMask{gp | sp | sb}, outputs: []regMask{fp}} + fploadidx = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb}, outputs: []regMask{fp}} fpstore = regInfo{inputs: []regMask{gp | sp | sb, fp}} + fpstoreidx = regInfo{inputs: []regMask{gp | sp | sb, gp | sp | sb, fp}} callerSave = regMask(gp | fp | gr) ) ops := []opData{ @@ -170,6 +175,7 @@ func init() { {name: "MULHW", argLength: 2, reg: gp21, asm: "MULHW", commutative: true}, // (arg0 * arg1) >> 32, signed {name: "MULHDU", argLength: 2, reg: gp21, asm: "MULHDU", commutative: true}, // (arg0 * arg1) >> 64, unsigned {name: "MULHWU", argLength: 2, reg: gp21, asm: "MULHWU", commutative: true}, // (arg0 * arg1) >> 32, unsigned + {name: "LoweredMuluhilo", argLength: 2, reg: gp22, resultNotInArgs: true}, // arg0 * arg1, returns (hi, lo) {name: "FMUL", argLength: 2, reg: fp21, asm: "FMUL", commutative: true}, // arg0*arg1 {name: "FMULS", argLength: 2, reg: fp21, asm: "FMULS", commutative: true}, // arg0*arg1 @@ -281,6 +287,19 @@ func init() { {name: "MOVWBRload", argLength: 2, reg: gpload, asm: "MOVWBR", aux: "SymOff", typ: "Int32", faultOnNilArg0: true, symEffect: "Read"}, // load 4 bytes zero extend reverse order {name: "MOVHBRload", argLength: 2, reg: gpload, asm: "MOVHBR", aux: "SymOff", typ: "Int16", faultOnNilArg0: true, symEffect: "Read"}, // load 2 bytes zero extend reverse order + // In these cases an index register is used in addition to a base register + {name: "MOVBZloadidx", argLength: 3, reg: gploadidx, asm: "MOVBZ", aux: "SymOff", typ: "UInt8", faultOnNilArg0: true, symEffect: "Read"}, // zero extend uint8 to uint64 + {name: "MOVHloadidx", argLength: 3, reg: gploadidx, asm: "MOVH", aux: "SymOff", typ: "Int16", faultOnNilArg0: true, symEffect: "Read"}, // sign extend int16 to int64 + {name: "MOVHZloadidx", argLength: 3, reg: gploadidx, asm: "MOVHZ", aux: "SymOff", typ: "UInt16", faultOnNilArg0: true, symEffect: "Read"}, // zero extend uint16 to uint64 + {name: "MOVWloadidx", argLength: 3, reg: gploadidx, asm: "MOVW", aux: "SymOff", typ: "Int32", faultOnNilArg0: true, symEffect: "Read"}, // sign extend int32 to int64 + {name: "MOVWZloadidx", argLength: 3, reg: gploadidx, asm: "MOVWZ", aux: "SymOff", typ: "UInt32", faultOnNilArg0: true, symEffect: "Read"}, // zero extend uint32 to uint64 + {name: "MOVDloadidx", argLength: 3, reg: gploadidx, asm: "MOVD", aux: "SymOff", typ: "Int64", faultOnNilArg0: true, symEffect: "Read"}, + {name: "MOVHBRloadidx", argLength: 3, reg: gploadidx, asm: "MOVHBR", aux: "SymOff", typ: "Int16", faultOnNilArg0: true, symEffect: "Read"}, // sign extend int16 to int64 + {name: "MOVWBRloadidx", argLength: 3, reg: gploadidx, asm: "MOVWBR", aux: "SymOff", typ: "Int32", faultOnNilArg0: true, symEffect: "Read"}, // sign extend int32 to int64 + {name: "MOVDBRloadidx", argLength: 3, reg: gploadidx, asm: "MOVDBR", aux: "SymOff", typ: "Int64", faultOnNilArg0: true, symEffect: "Read"}, + {name: "FMOVDloadidx", argLength: 3, reg: fploadidx, asm: "FMOVD", aux: "SymOff", typ: "Float64", faultOnNilArg0: true, symEffect: "Read"}, + {name: "FMOVSloadidx", argLength: 3, reg: fploadidx, asm: "FMOVS", aux: "SymOff", typ: "Float32", faultOnNilArg0: true, symEffect: "Read"}, + // Store bytes in the reverse endian order of the arch into arg0. // These are indexes stores with no offset field in the instruction so the aux fields are not used. {name: "MOVDBRstore", argLength: 3, reg: gpstore, asm: "MOVDBR", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store 8 bytes reverse order @@ -301,6 +320,17 @@ func init() { {name: "FMOVDstore", argLength: 3, reg: fpstore, asm: "FMOVD", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store double flot {name: "FMOVSstore", argLength: 3, reg: fpstore, asm: "FMOVS", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store single float + // Stores using index and base registers + {name: "MOVBstoreidx", argLength: 4, reg: gpstoreidx, asm: "MOVB", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store bye + {name: "MOVHstoreidx", argLength: 4, reg: gpstoreidx, asm: "MOVH", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store half word + {name: "MOVWstoreidx", argLength: 4, reg: gpstoreidx, asm: "MOVW", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store word + {name: "MOVDstoreidx", argLength: 4, reg: gpstoreidx, asm: "MOVD", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store double word + {name: "FMOVDstoreidx", argLength: 4, reg: fpstoreidx, asm: "FMOVD", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store double float + {name: "FMOVSstoreidx", argLength: 4, reg: fpstoreidx, asm: "FMOVS", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store single float + {name: "MOVHBRstoreidx", argLength: 4, reg: gpstoreidx, asm: "MOVHBR", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store half word reversed byte using index reg + {name: "MOVWBRstoreidx", argLength: 4, reg: gpstoreidx, asm: "MOVWBR", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store word reversed byte using index reg + {name: "MOVDBRstoreidx", argLength: 4, reg: gpstoreidx, asm: "MOVDBR", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store double word reversed byte using index reg + // The following ops store 0 into arg0+aux+auxint arg1=mem {name: "MOVBstorezero", argLength: 2, reg: gpstorezero, asm: "MOVB", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store zero 1 byte {name: "MOVHstorezero", argLength: 2, reg: gpstorezero, asm: "MOVH", aux: "SymOff", typ: "Mem", faultOnNilArg0: true, symEffect: "Write"}, // store zero 2 bytes diff --git a/src/cmd/compile/internal/ssa/gen/Wasm.rules b/src/cmd/compile/internal/ssa/gen/Wasm.rules index dc1581362c..64198839d0 100644 --- a/src/cmd/compile/internal/ssa/gen/Wasm.rules +++ b/src/cmd/compile/internal/ssa/gen/Wasm.rules @@ -363,8 +363,8 @@ (I64And (I64Const [x]) (I64Const [y])) -> (I64Const [x & y]) (I64Or (I64Const [x]) (I64Const [y])) -> (I64Const [x | y]) (I64Xor (I64Const [x]) (I64Const [y])) -> (I64Const [x ^ y]) -(F64Add (F64Const [x]) (F64Const [y])) -> (F64Const [f2i(i2f(x) + i2f(y))]) -(F64Mul (F64Const [x]) (F64Const [y])) -> (F64Const [f2i(i2f(x) * i2f(y))]) +(F64Add (F64Const [x]) (F64Const [y])) -> (F64Const [auxFrom64F(auxTo64F(x) + auxTo64F(y))]) +(F64Mul (F64Const [x]) (F64Const [y])) -> (F64Const [auxFrom64F(auxTo64F(x) * auxTo64F(y))]) (I64Eq (I64Const [x]) (I64Const [y])) && x == y -> (I64Const [1]) (I64Eq (I64Const [x]) (I64Const [y])) && x != y -> (I64Const [0]) (I64Ne (I64Const [x]) (I64Const [y])) && x == y -> (I64Const [0]) diff --git a/src/cmd/compile/internal/ssa/gen/generic.rules b/src/cmd/compile/internal/ssa/gen/generic.rules index aa944b5379..d490e32f3d 100644 --- a/src/cmd/compile/internal/ssa/gen/generic.rules +++ b/src/cmd/compile/internal/ssa/gen/generic.rules @@ -44,16 +44,16 @@ (Trunc64to8 (Const64 [c])) -> (Const8 [int64(int8(c))]) (Trunc64to16 (Const64 [c])) -> (Const16 [int64(int16(c))]) (Trunc64to32 (Const64 [c])) -> (Const32 [int64(int32(c))]) -(Cvt64Fto32F (Const64F [c])) -> (Const32F [f2i(float64(i2f32(c)))]) +(Cvt64Fto32F (Const64F [c])) -> (Const32F [auxFrom32F(float32(auxTo64F(c)))]) (Cvt32Fto64F (Const32F [c])) -> (Const64F [c]) // c is already a 64 bit float -(Cvt32to32F (Const32 [c])) -> (Const32F [f2i(float64(float32(int32(c))))]) -(Cvt32to64F (Const32 [c])) -> (Const64F [f2i(float64(int32(c)))]) -(Cvt64to32F (Const64 [c])) -> (Const32F [f2i(float64(float32(c)))]) -(Cvt64to64F (Const64 [c])) -> (Const64F [f2i(float64(c))]) -(Cvt32Fto32 (Const32F [c])) -> (Const32 [int64(int32(i2f(c)))]) -(Cvt32Fto64 (Const32F [c])) -> (Const64 [int64(i2f(c))]) -(Cvt64Fto32 (Const64F [c])) -> (Const32 [int64(int32(i2f(c)))]) -(Cvt64Fto64 (Const64F [c])) -> (Const64 [int64(i2f(c))]) +(Cvt32to32F (Const32 [c])) -> (Const32F [auxFrom32F(float32(int32(c)))]) +(Cvt32to64F (Const32 [c])) -> (Const64F [auxFrom64F(float64(int32(c)))]) +(Cvt64to32F (Const64 [c])) -> (Const32F [auxFrom32F(float32(c))]) +(Cvt64to64F (Const64 [c])) -> (Const64F [auxFrom64F(float64(c))]) +(Cvt32Fto32 (Const32F [c])) -> (Const32 [int64(int32(auxTo32F(c)))]) +(Cvt32Fto64 (Const32F [c])) -> (Const64 [int64(auxTo32F(c))]) +(Cvt64Fto32 (Const64F [c])) -> (Const32 [int64(int32(auxTo64F(c)))]) +(Cvt64Fto64 (Const64F [c])) -> (Const64 [int64(auxTo64F(c))]) (Round32F x:(Const32F)) -> x (Round64F x:(Const64F)) -> x @@ -95,16 +95,15 @@ (Neg16 (Const16 [c])) -> (Const16 [int64(-int16(c))]) (Neg32 (Const32 [c])) -> (Const32 [int64(-int32(c))]) (Neg64 (Const64 [c])) -> (Const64 [-c]) -(Neg32F (Const32F [c])) && i2f(c) != 0 -> (Const32F [f2i(-i2f(c))]) -(Neg64F (Const64F [c])) && i2f(c) != 0 -> (Const64F [f2i(-i2f(c))]) +(Neg32F (Const32F [c])) && auxTo32F(c) != 0 -> (Const32F [auxFrom32F(-auxTo32F(c))]) +(Neg64F (Const64F [c])) && auxTo64F(c) != 0 -> (Const64F [auxFrom64F(-auxTo64F(c))]) (Add8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c+d))]) (Add16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c+d))]) (Add32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c+d))]) (Add64 (Const64 [c]) (Const64 [d])) -> (Const64 [c+d]) -(Add32F (Const32F [c]) (Const32F [d])) -> - (Const32F [f2i(float64(i2f32(c) + i2f32(d)))]) // ensure we combine the operands with 32 bit precision -(Add64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) + i2f(d))]) +(Add32F (Const32F [c]) (Const32F [d])) -> (Const32F [auxFrom32F(auxTo32F(c) + auxTo32F(d))]) +(Add64F (Const64F [c]) (Const64F [d])) -> (Const64F [auxFrom64F(auxTo64F(c) + auxTo64F(d))]) (AddPtr <t> x (Const64 [c])) -> (OffPtr <t> x [c]) (AddPtr <t> x (Const32 [c])) -> (OffPtr <t> x [c]) @@ -112,17 +111,15 @@ (Sub16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c-d))]) (Sub32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c-d))]) (Sub64 (Const64 [c]) (Const64 [d])) -> (Const64 [c-d]) -(Sub32F (Const32F [c]) (Const32F [d])) -> - (Const32F [f2i(float64(i2f32(c) - i2f32(d)))]) -(Sub64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) - i2f(d))]) +(Sub32F (Const32F [c]) (Const32F [d])) -> (Const32F [auxFrom32F(auxTo32F(c) - auxTo32F(d))]) +(Sub64F (Const64F [c]) (Const64F [d])) -> (Const64F [auxFrom64F(auxTo64F(c) - auxTo64F(d))]) (Mul8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c*d))]) (Mul16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c*d))]) (Mul32 (Const32 [c]) (Const32 [d])) -> (Const32 [int64(int32(c*d))]) (Mul64 (Const64 [c]) (Const64 [d])) -> (Const64 [c*d]) -(Mul32F (Const32F [c]) (Const32F [d])) -> - (Const32F [f2i(float64(i2f32(c) * i2f32(d)))]) -(Mul64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) * i2f(d))]) +(Mul32F (Const32F [c]) (Const32F [d])) -> (Const32F [auxFrom32F(auxTo32F(c) * auxTo32F(d))]) +(Mul64F (Const64F [c]) (Const64F [d])) -> (Const64F [auxFrom64F(auxTo64F(c) * auxTo64F(d))]) (And8 (Const8 [c]) (Const8 [d])) -> (Const8 [int64(int8(c&d))]) (And16 (Const16 [c]) (Const16 [d])) -> (Const16 [int64(int16(c&d))]) @@ -147,8 +144,8 @@ (Div16u (Const16 [c]) (Const16 [d])) && d != 0 -> (Const16 [int64(int16(uint16(c)/uint16(d)))]) (Div32u (Const32 [c]) (Const32 [d])) && d != 0 -> (Const32 [int64(int32(uint32(c)/uint32(d)))]) (Div64u (Const64 [c]) (Const64 [d])) && d != 0 -> (Const64 [int64(uint64(c)/uint64(d))]) -(Div32F (Const32F [c]) (Const32F [d])) -> (Const32F [f2i(float64(i2f32(c) / i2f32(d)))]) -(Div64F (Const64F [c]) (Const64F [d])) -> (Const64F [f2i(i2f(c) / i2f(d))]) +(Div32F (Const32F [c]) (Const32F [d])) -> (Const32F [auxFrom32F(auxTo32F(c) / auxTo32F(d))]) +(Div64F (Const64F [c]) (Const64F [d])) -> (Const64F [auxFrom64F(auxTo64F(c) / auxTo64F(d))]) (Not (ConstBool [c])) -> (ConstBool [1-c]) @@ -444,12 +441,18 @@ (Leq8U (Const8 [c]) (Const8 [d])) -> (ConstBool [b2i(uint8(c) <= uint8(d))]) // constant floating point comparisons -(Eq(64|32)F (Const(64|32)F [c]) (Const(64|32)F [d])) -> (ConstBool [b2i(i2f(c) == i2f(d))]) -(Neq(64|32)F (Const(64|32)F [c]) (Const(64|32)F [d])) -> (ConstBool [b2i(i2f(c) != i2f(d))]) -(Greater(64|32)F (Const(64|32)F [c]) (Const(64|32)F [d])) -> (ConstBool [b2i(i2f(c) > i2f(d))]) -(Geq(64|32)F (Const(64|32)F [c]) (Const(64|32)F [d])) -> (ConstBool [b2i(i2f(c) >= i2f(d))]) -(Less(64|32)F (Const(64|32)F [c]) (Const(64|32)F [d])) -> (ConstBool [b2i(i2f(c) < i2f(d))]) -(Leq(64|32)F (Const(64|32)F [c]) (Const(64|32)F [d])) -> (ConstBool [b2i(i2f(c) <= i2f(d))]) +(Eq32F (Const32F [c]) (Const32F [d])) -> (ConstBool [b2i(auxTo32F(c) == auxTo32F(d))]) +(Eq64F (Const64F [c]) (Const64F [d])) -> (ConstBool [b2i(auxTo64F(c) == auxTo64F(d))]) +(Neq32F (Const32F [c]) (Const32F [d])) -> (ConstBool [b2i(auxTo32F(c) != auxTo32F(d))]) +(Neq64F (Const64F [c]) (Const64F [d])) -> (ConstBool [b2i(auxTo64F(c) != auxTo64F(d))]) +(Greater32F (Const32F [c]) (Const32F [d])) -> (ConstBool [b2i(auxTo32F(c) > auxTo32F(d))]) +(Greater64F (Const64F [c]) (Const64F [d])) -> (ConstBool [b2i(auxTo64F(c) > auxTo64F(d))]) +(Geq32F (Const32F [c]) (Const32F [d])) -> (ConstBool [b2i(auxTo32F(c) >= auxTo32F(d))]) +(Geq64F (Const64F [c]) (Const64F [d])) -> (ConstBool [b2i(auxTo64F(c) >= auxTo64F(d))]) +(Less32F (Const32F [c]) (Const32F [d])) -> (ConstBool [b2i(auxTo32F(c) < auxTo32F(d))]) +(Less64F (Const64F [c]) (Const64F [d])) -> (ConstBool [b2i(auxTo64F(c) < auxTo64F(d))]) +(Leq32F (Const32F [c]) (Const32F [d])) -> (ConstBool [b2i(auxTo32F(c) <= auxTo32F(d))]) +(Leq64F (Const64F [c]) (Const64F [d])) -> (ConstBool [b2i(auxTo64F(c) <= auxTo64F(d))]) // simplifications (Or(64|32|16|8) x x) -> x @@ -572,9 +575,9 @@ // Pass constants through math.Float{32,64}bits and math.Float{32,64}frombits (Load <t1> p1 (Store {t2} p2 (Const64 [x]) _)) && isSamePtr(p1,p2) && sizeof(t2) == 8 && is64BitFloat(t1) -> (Const64F [x]) -(Load <t1> p1 (Store {t2} p2 (Const32 [x]) _)) && isSamePtr(p1,p2) && sizeof(t2) == 4 && is32BitFloat(t1) -> (Const32F [f2i(extend32Fto64F(math.Float32frombits(uint32(x))))]) +(Load <t1> p1 (Store {t2} p2 (Const32 [x]) _)) && isSamePtr(p1,p2) && sizeof(t2) == 4 && is32BitFloat(t1) -> (Const32F [auxFrom32F(math.Float32frombits(uint32(x)))]) (Load <t1> p1 (Store {t2} p2 (Const64F [x]) _)) && isSamePtr(p1,p2) && sizeof(t2) == 8 && is64BitInt(t1) -> (Const64 [x]) -(Load <t1> p1 (Store {t2} p2 (Const32F [x]) _)) && isSamePtr(p1,p2) && sizeof(t2) == 4 && is32BitInt(t1) -> (Const32 [int64(int32(math.Float32bits(truncate64Fto32F(i2f(x)))))]) +(Load <t1> p1 (Store {t2} p2 (Const32F [x]) _)) && isSamePtr(p1,p2) && sizeof(t2) == 4 && is32BitInt(t1) -> (Const32 [int64(int32(math.Float32bits(auxTo32F(x))))]) // Float Loads up to Zeros so they can be constant folded. (Load <t1> op:(OffPtr [o1] p1) @@ -1326,19 +1329,16 @@ (Mul8 (Const8 <t> [c]) (Mul8 (Const8 <t> [d]) x)) -> (Mul8 (Const8 <t> [int64(int8(c*d))]) x) // floating point optimizations -(Add(32|64)F x (Const(32|64)F [0])) -> x -(Sub(32|64)F x (Const(32|64)F [0])) -> x +(Mul(32|64)F x (Const(32|64)F [auxFrom64F(1)])) -> x +(Mul32F x (Const32F [auxFrom32F(-1)])) -> (Neg32F x) +(Mul64F x (Const64F [auxFrom64F(-1)])) -> (Neg64F x) +(Mul32F x (Const32F [auxFrom32F(2)])) -> (Add32F x x) +(Mul64F x (Const64F [auxFrom64F(2)])) -> (Add64F x x) -(Mul(32|64)F x (Const(32|64)F [f2i(1)])) -> x -(Mul32F x (Const32F [f2i(-1)])) -> (Neg32F x) -(Mul64F x (Const64F [f2i(-1)])) -> (Neg64F x) -(Mul32F x (Const32F [f2i(2)])) -> (Add32F x x) -(Mul64F x (Const64F [f2i(2)])) -> (Add64F x x) +(Div32F x (Const32F <t> [c])) && reciprocalExact32(auxTo32F(c)) -> (Mul32F x (Const32F <t> [auxFrom32F(1/auxTo32F(c))])) +(Div64F x (Const64F <t> [c])) && reciprocalExact64(auxTo64F(c)) -> (Mul64F x (Const64F <t> [auxFrom64F(1/auxTo64F(c))])) -(Div32F x (Const32F <t> [c])) && reciprocalExact32(float32(i2f(c))) -> (Mul32F x (Const32F <t> [f2i(1/i2f(c))])) -(Div64F x (Const64F <t> [c])) && reciprocalExact64(i2f(c)) -> (Mul64F x (Const64F <t> [f2i(1/i2f(c))])) - -(Sqrt (Const64F [c])) -> (Const64F [f2i(math.Sqrt(i2f(c)))]) +(Sqrt (Const64F [c])) -> (Const64F [auxFrom64F(math.Sqrt(auxTo64F(c)))]) // recognize runtime.newobject and don't Zero/Nilcheck it (Zero (Load (OffPtr [c] (SP)) mem) mem) @@ -1363,12 +1363,12 @@ (NilCheck (Load (OffPtr [c] (SP)) (StaticCall {sym} _)) _) && isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize() + config.RegSize // offset of return value - && warnRule(fe.Debug_checknil() && v.Pos.Line() > 1, v, "removed nil check") + && warnRule(fe.Debug_checknil(), v, "removed nil check") -> (Invalid) (NilCheck (OffPtr (Load (OffPtr [c] (SP)) (StaticCall {sym} _))) _) && isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize() + config.RegSize // offset of return value - && warnRule(fe.Debug_checknil() && v.Pos.Line() > 1, v, "removed nil check") + && warnRule(fe.Debug_checknil(), v, "removed nil check") -> (Invalid) // Evaluate constant address comparisons. @@ -1545,8 +1545,8 @@ // Don't Move from memory if the values are likely to already be // in registers. (Move {t1} [n] dst p1 - mem:(Store {t2} op2:(OffPtr [o2] p2) d1 - (Store {t3} op3:(OffPtr [0] p3) d2 _))) + mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 + (Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _))) && isSamePtr(p1, p2) && isSamePtr(p2, p3) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) @@ -1554,12 +1554,12 @@ && registerizable(b, t3) && o2 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) - -> (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 - (Store {t3} (OffPtr <t3.(*types.Type)> [0] dst) d2 mem)) + -> (Store {t2} (OffPtr <tt2> [o2] dst) d1 + (Store {t3} (OffPtr <tt3> [0] dst) d2 mem)) (Move {t1} [n] dst p1 - mem:(Store {t2} op2:(OffPtr [o2] p2) d1 - (Store {t3} op3:(OffPtr [o3] p3) d2 - (Store {t4} op4:(OffPtr [0] p4) d3 _)))) + mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 + (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2 + (Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _)))) && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) @@ -1570,14 +1570,14 @@ && o3 == sizeof(t4) && o2-o3 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) + sizeof(t4) - -> (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 - (Store {t3} (OffPtr <t3.(*types.Type)> [o3] dst) d2 - (Store {t4} (OffPtr <t4.(*types.Type)> [0] dst) d3 mem))) + -> (Store {t2} (OffPtr <tt2> [o2] dst) d1 + (Store {t3} (OffPtr <tt3> [o3] dst) d2 + (Store {t4} (OffPtr <tt4> [0] dst) d3 mem))) (Move {t1} [n] dst p1 - mem:(Store {t2} op2:(OffPtr [o2] p2) d1 - (Store {t3} op3:(OffPtr [o3] p3) d2 - (Store {t4} op4:(OffPtr [o4] p4) d3 - (Store {t5} op5:(OffPtr [0] p5) d4 _))))) + mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 + (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2 + (Store {t4} op4:(OffPtr <tt4> [o4] p4) d3 + (Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _))))) && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) @@ -1591,16 +1591,16 @@ && o3-o4 == sizeof(t4) && o2-o3 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) + sizeof(t4) + sizeof(t5) - -> (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 - (Store {t3} (OffPtr <t3.(*types.Type)> [o3] dst) d2 - (Store {t4} (OffPtr <t4.(*types.Type)> [o4] dst) d3 - (Store {t5} (OffPtr <t5.(*types.Type)> [0] dst) d4 mem)))) + -> (Store {t2} (OffPtr <tt2> [o2] dst) d1 + (Store {t3} (OffPtr <tt3> [o3] dst) d2 + (Store {t4} (OffPtr <tt4> [o4] dst) d3 + (Store {t5} (OffPtr <tt5> [0] dst) d4 mem)))) // Same thing but with VarDef in the middle. (Move {t1} [n] dst p1 mem:(VarDef - (Store {t2} op2:(OffPtr [o2] p2) d1 - (Store {t3} op3:(OffPtr [0] p3) d2 _)))) + (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 + (Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _)))) && isSamePtr(p1, p2) && isSamePtr(p2, p3) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) @@ -1608,13 +1608,13 @@ && registerizable(b, t3) && o2 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) - -> (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 - (Store {t3} (OffPtr <t3.(*types.Type)> [0] dst) d2 mem)) + -> (Store {t2} (OffPtr <tt2> [o2] dst) d1 + (Store {t3} (OffPtr <tt3> [0] dst) d2 mem)) (Move {t1} [n] dst p1 mem:(VarDef - (Store {t2} op2:(OffPtr [o2] p2) d1 - (Store {t3} op3:(OffPtr [o3] p3) d2 - (Store {t4} op4:(OffPtr [0] p4) d3 _))))) + (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 + (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2 + (Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _))))) && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) @@ -1625,15 +1625,15 @@ && o3 == sizeof(t4) && o2-o3 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) + sizeof(t4) - -> (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 - (Store {t3} (OffPtr <t3.(*types.Type)> [o3] dst) d2 - (Store {t4} (OffPtr <t4.(*types.Type)> [0] dst) d3 mem))) + -> (Store {t2} (OffPtr <tt2> [o2] dst) d1 + (Store {t3} (OffPtr <tt3> [o3] dst) d2 + (Store {t4} (OffPtr <tt4> [0] dst) d3 mem))) (Move {t1} [n] dst p1 mem:(VarDef - (Store {t2} op2:(OffPtr [o2] p2) d1 - (Store {t3} op3:(OffPtr [o3] p3) d2 - (Store {t4} op4:(OffPtr [o4] p4) d3 - (Store {t5} op5:(OffPtr [0] p5) d4 _)))))) + (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 + (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2 + (Store {t4} op4:(OffPtr <tt4> [o4] p4) d3 + (Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _)))))) && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) @@ -1647,10 +1647,10 @@ && o3-o4 == sizeof(t4) && o2-o3 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) + sizeof(t4) + sizeof(t5) - -> (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 - (Store {t3} (OffPtr <t3.(*types.Type)> [o3] dst) d2 - (Store {t4} (OffPtr <t4.(*types.Type)> [o4] dst) d3 - (Store {t5} (OffPtr <t5.(*types.Type)> [0] dst) d4 mem)))) + -> (Store {t2} (OffPtr <tt2> [o2] dst) d1 + (Store {t3} (OffPtr <tt3> [o3] dst) d2 + (Store {t4} (OffPtr <tt4> [o4] dst) d3 + (Store {t5} (OffPtr <tt5> [0] dst) d4 mem)))) // Prefer to Zero and Store than to Move. (Move {t1} [n] dst p1 diff --git a/src/cmd/compile/internal/ssa/gen/genericOps.go b/src/cmd/compile/internal/ssa/gen/genericOps.go index 7292012d26..ee9c6fa0f6 100644 --- a/src/cmd/compile/internal/ssa/gen/genericOps.go +++ b/src/cmd/compile/internal/ssa/gen/genericOps.go @@ -470,8 +470,9 @@ var genericOps = []opData{ {name: "VarDef", argLength: 1, aux: "Sym", typ: "Mem", symEffect: "None", zeroWidth: true}, // aux is a *gc.Node of a variable that is about to be initialized. arg0=mem, returns mem {name: "VarKill", argLength: 1, aux: "Sym", symEffect: "None"}, // aux is a *gc.Node of a variable that is known to be dead. arg0=mem, returns mem - {name: "VarLive", argLength: 1, aux: "Sym", symEffect: "Read", zeroWidth: true}, // aux is a *gc.Node of a variable that must be kept live. arg0=mem, returns mem - {name: "KeepAlive", argLength: 2, typ: "Mem", zeroWidth: true}, // arg[0] is a value that must be kept alive until this mark. arg[1]=mem, returns mem + // TODO: what's the difference betweeen VarLive and KeepAlive? + {name: "VarLive", argLength: 1, aux: "Sym", symEffect: "Read", zeroWidth: true}, // aux is a *gc.Node of a variable that must be kept live. arg0=mem, returns mem + {name: "KeepAlive", argLength: 2, typ: "Mem", zeroWidth: true}, // arg[0] is a value that must be kept alive until this mark. arg[1]=mem, returns mem // Ops for breaking 64-bit operations on 32-bit architectures {name: "Int64Make", argLength: 2, typ: "UInt64"}, // arg0=hi, arg1=lo diff --git a/src/cmd/compile/internal/ssa/gen/main.go b/src/cmd/compile/internal/ssa/gen/main.go index f35a991db2..f7195bf536 100644 --- a/src/cmd/compile/internal/ssa/gen/main.go +++ b/src/cmd/compile/internal/ssa/gen/main.go @@ -63,9 +63,14 @@ type blockData struct { } type regInfo struct { - inputs []regMask + // inputs[i] encodes the set of registers allowed for the i'th input. + // Inputs that don't use registers (flags, memory, etc.) should be 0. + inputs []regMask + // clobbers encodes the set of registers that are overwritten by + // the instruction (other than the output registers). clobbers regMask - outputs []regMask + // outpus[i] encodes the set of registers allowed for the i'th output. + outputs []regMask } type regMask uint64 diff --git a/src/cmd/compile/internal/ssa/html.go b/src/cmd/compile/internal/ssa/html.go index c51ea02262..b7d5f912db 100644 --- a/src/cmd/compile/internal/ssa/html.go +++ b/src/cmd/compile/internal/ssa/html.go @@ -484,7 +484,7 @@ func (x ByTopo) Swap(i, j int) { x[i], x[j] = x[j], x[i] } func (x ByTopo) Less(i, j int) bool { a := x[i] b := x[j] - if a.Filename == a.Filename { + if a.Filename == b.Filename { return a.StartLineno < b.StartLineno } return a.Filename < b.Filename diff --git a/src/cmd/compile/internal/ssa/op.go b/src/cmd/compile/internal/ssa/op.go index 610921808e..43f5c59591 100644 --- a/src/cmd/compile/internal/ssa/op.go +++ b/src/cmd/compile/internal/ssa/op.go @@ -50,9 +50,17 @@ type outputInfo struct { } type regInfo struct { - inputs []inputInfo // ordered in register allocation order + // inputs encodes the register restrictions for an instruction's inputs. + // Each entry specifies an allowed register set for a particular input. + // They are listed in the order in which regalloc should pick a register + // from the register set (most constrained first). + // Inputs which do not need registers are not listed. + inputs []inputInfo + // clobbers encodes the set of registers that are overwritten by + // the instruction (other than the output registers). clobbers regMask - outputs []outputInfo // ordered in register allocation order + // outputs is the same as inputs, but for the outputs of the instruction. + outputs []outputInfo } type auxType int8 diff --git a/src/cmd/compile/internal/ssa/opGen.go b/src/cmd/compile/internal/ssa/opGen.go index 5bf7021432..2145c6e723 100644 --- a/src/cmd/compile/internal/ssa/opGen.go +++ b/src/cmd/compile/internal/ssa/opGen.go @@ -550,6 +550,18 @@ const ( OpAMD64BTRQconst OpAMD64BTSLconst OpAMD64BTSQconst + OpAMD64BTCQmodify + OpAMD64BTCLmodify + OpAMD64BTSQmodify + OpAMD64BTSLmodify + OpAMD64BTRQmodify + OpAMD64BTRLmodify + OpAMD64BTCQconstmodify + OpAMD64BTCLconstmodify + OpAMD64BTSQconstmodify + OpAMD64BTSLconstmodify + OpAMD64BTRQconstmodify + OpAMD64BTRLconstmodify OpAMD64TESTQ OpAMD64TESTL OpAMD64TESTW @@ -1107,6 +1119,7 @@ const ( OpARM64LoweredMuluhilo OpARM64MVN OpARM64NEG + OpARM64FABSD OpARM64FNEGS OpARM64FNEGD OpARM64FSQRTD @@ -1139,6 +1152,8 @@ const ( OpARM64SRLconst OpARM64SRA OpARM64SRAconst + OpARM64ROR + OpARM64RORW OpARM64RORconst OpARM64RORWconst OpARM64EXTRconst @@ -1157,6 +1172,12 @@ const ( OpARM64TSTWconst OpARM64FCMPS OpARM64FCMPD + OpARM64MVNshiftLL + OpARM64MVNshiftRL + OpARM64MVNshiftRA + OpARM64NEGshiftLL + OpARM64NEGshiftRL + OpARM64NEGshiftRA OpARM64ADDshiftLL OpARM64ADDshiftRL OpARM64ADDshiftRA @@ -1184,6 +1205,12 @@ const ( OpARM64CMPshiftLL OpARM64CMPshiftRL OpARM64CMPshiftRA + OpARM64CMNshiftLL + OpARM64CMNshiftRL + OpARM64CMNshiftRA + OpARM64TSTshiftLL + OpARM64TSTshiftRL + OpARM64TSTshiftRA OpARM64BFI OpARM64BFXIL OpARM64SBFIZ @@ -1247,6 +1274,8 @@ const ( OpARM64MOVDstorezeroidx8 OpARM64FMOVDgpfp OpARM64FMOVDfpgp + OpARM64FMOVSgpfp + OpARM64FMOVSfpgp OpARM64MOVBreg OpARM64MOVBUreg OpARM64MOVHreg @@ -1275,6 +1304,7 @@ const ( OpARM64FCVTDS OpARM64FRINTAD OpARM64FRINTMD + OpARM64FRINTND OpARM64FRINTPD OpARM64FRINTZD OpARM64CSEL @@ -1551,6 +1581,7 @@ const ( OpPPC64MULHW OpPPC64MULHDU OpPPC64MULHWU + OpPPC64LoweredMuluhilo OpPPC64FMUL OpPPC64FMULS OpPPC64FMADD @@ -1630,6 +1661,17 @@ const ( OpPPC64MOVDBRload OpPPC64MOVWBRload OpPPC64MOVHBRload + OpPPC64MOVBZloadidx + OpPPC64MOVHloadidx + OpPPC64MOVHZloadidx + OpPPC64MOVWloadidx + OpPPC64MOVWZloadidx + OpPPC64MOVDloadidx + OpPPC64MOVHBRloadidx + OpPPC64MOVWBRloadidx + OpPPC64MOVDBRloadidx + OpPPC64FMOVDloadidx + OpPPC64FMOVSloadidx OpPPC64MOVDBRstore OpPPC64MOVWBRstore OpPPC64MOVHBRstore @@ -1641,6 +1683,15 @@ const ( OpPPC64MOVDstore OpPPC64FMOVDstore OpPPC64FMOVSstore + OpPPC64MOVBstoreidx + OpPPC64MOVHstoreidx + OpPPC64MOVWstoreidx + OpPPC64MOVDstoreidx + OpPPC64FMOVDstoreidx + OpPPC64FMOVSstoreidx + OpPPC64MOVHBRstoreidx + OpPPC64MOVWBRstoreidx + OpPPC64MOVDBRstoreidx OpPPC64MOVBstorezero OpPPC64MOVHstorezero OpPPC64MOVWstorezero @@ -6896,6 +6947,180 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "BTCQmodify", + auxType: auxSymOff, + argLen: 3, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTCQ, + reg: regInfo{ + inputs: []inputInfo{ + {1, 65535}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTCLmodify", + auxType: auxSymOff, + argLen: 3, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTCL, + reg: regInfo{ + inputs: []inputInfo{ + {1, 65535}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTSQmodify", + auxType: auxSymOff, + argLen: 3, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTSQ, + reg: regInfo{ + inputs: []inputInfo{ + {1, 65535}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTSLmodify", + auxType: auxSymOff, + argLen: 3, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTSL, + reg: regInfo{ + inputs: []inputInfo{ + {1, 65535}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTRQmodify", + auxType: auxSymOff, + argLen: 3, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTRQ, + reg: regInfo{ + inputs: []inputInfo{ + {1, 65535}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTRLmodify", + auxType: auxSymOff, + argLen: 3, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTRL, + reg: regInfo{ + inputs: []inputInfo{ + {1, 65535}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTCQconstmodify", + auxType: auxSymValAndOff, + argLen: 2, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTCQ, + reg: regInfo{ + inputs: []inputInfo{ + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTCLconstmodify", + auxType: auxSymValAndOff, + argLen: 2, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTCL, + reg: regInfo{ + inputs: []inputInfo{ + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTSQconstmodify", + auxType: auxSymValAndOff, + argLen: 2, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTSQ, + reg: regInfo{ + inputs: []inputInfo{ + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTSLconstmodify", + auxType: auxSymValAndOff, + argLen: 2, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTSL, + reg: regInfo{ + inputs: []inputInfo{ + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTRQconstmodify", + auxType: auxSymValAndOff, + argLen: 2, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTRQ, + reg: regInfo{ + inputs: []inputInfo{ + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { + name: "BTRLconstmodify", + auxType: auxSymValAndOff, + argLen: 2, + clobberFlags: true, + faultOnNilArg0: true, + symEffect: SymRead | SymWrite, + asm: x86.ABTRL, + reg: regInfo{ + inputs: []inputInfo{ + {0, 4295032831}, // AX CX DX BX SP BP SI DI R8 R9 R10 R11 R12 R13 R14 R15 SB + }, + }, + }, + { name: "TESTQ", argLen: 2, commutative: true, @@ -14657,6 +14882,19 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "FABSD", + argLen: 1, + asm: arm64.AFABSD, + reg: regInfo{ + inputs: []inputInfo{ + {0, 9223372034707292160}, // F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 F27 F28 F29 F30 F31 + }, + outputs: []outputInfo{ + {0, 9223372034707292160}, // F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 F27 F28 F29 F30 F31 + }, + }, + }, + { name: "FNEGS", argLen: 1, asm: arm64.AFNEGS, @@ -15105,6 +15343,34 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "ROR", + argLen: 2, + asm: arm64.AROR, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + {1, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { + name: "RORW", + argLen: 2, + asm: arm64.ARORW, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + {1, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { name: "RORconst", auxType: auxInt64, argLen: 1, @@ -15321,6 +15587,90 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "MVNshiftLL", + auxType: auxInt64, + argLen: 1, + asm: arm64.AMVN, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { + name: "MVNshiftRL", + auxType: auxInt64, + argLen: 1, + asm: arm64.AMVN, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { + name: "MVNshiftRA", + auxType: auxInt64, + argLen: 1, + asm: arm64.AMVN, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { + name: "NEGshiftLL", + auxType: auxInt64, + argLen: 1, + asm: arm64.ANEG, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { + name: "NEGshiftRL", + auxType: auxInt64, + argLen: 1, + asm: arm64.ANEG, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { + name: "NEGshiftRA", + auxType: auxInt64, + argLen: 1, + asm: arm64.ANEG, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { name: "ADDshiftLL", auxType: auxInt64, argLen: 2, @@ -15717,6 +16067,78 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "CMNshiftLL", + auxType: auxInt64, + argLen: 2, + asm: arm64.ACMN, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + {1, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + }, + }, + { + name: "CMNshiftRL", + auxType: auxInt64, + argLen: 2, + asm: arm64.ACMN, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + {1, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + }, + }, + { + name: "CMNshiftRA", + auxType: auxInt64, + argLen: 2, + asm: arm64.ACMN, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + {1, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + }, + }, + { + name: "TSTshiftLL", + auxType: auxInt64, + argLen: 2, + asm: arm64.ATST, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + {1, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + }, + }, + { + name: "TSTshiftRL", + auxType: auxInt64, + argLen: 2, + asm: arm64.ATST, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + {1, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + }, + }, + { + name: "TSTshiftRA", + auxType: auxInt64, + argLen: 2, + asm: arm64.ATST, + reg: regInfo{ + inputs: []inputInfo{ + {0, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + {1, 805044223}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 g R30 + }, + }, + }, + { name: "BFI", auxType: auxInt64, argLen: 2, @@ -16572,6 +16994,32 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "FMOVSgpfp", + argLen: 1, + asm: arm64.AFMOVS, + reg: regInfo{ + inputs: []inputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + outputs: []outputInfo{ + {0, 9223372034707292160}, // F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 F27 F28 F29 F30 F31 + }, + }, + }, + { + name: "FMOVSfpgp", + argLen: 1, + asm: arm64.AFMOVS, + reg: regInfo{ + inputs: []inputInfo{ + {0, 9223372034707292160}, // F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 F27 F28 F29 F30 F31 + }, + outputs: []outputInfo{ + {0, 670826495}, // R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R19 R20 R21 R22 R23 R24 R25 R26 R30 + }, + }, + }, + { name: "MOVBreg", argLen: 1, asm: arm64.AMOVB, @@ -16936,6 +17384,19 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "FRINTND", + argLen: 1, + asm: arm64.AFRINTND, + reg: regInfo{ + inputs: []inputInfo{ + {0, 9223372034707292160}, // F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 F27 F28 F29 F30 F31 + }, + outputs: []outputInfo{ + {0, 9223372034707292160}, // F0 F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 F27 F28 F29 F30 F31 + }, + }, + }, + { name: "FRINTPD", argLen: 1, asm: arm64.AFRINTPD, @@ -20590,6 +21051,21 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "LoweredMuluhilo", + argLen: 2, + resultNotInArgs: true, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { name: "FMUL", argLen: 2, commutative: true, @@ -21691,6 +22167,193 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "MOVBZloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVBZ, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVHloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVH, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVHZloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVHZ, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVWloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVW, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVWZloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVWZ, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVDloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVD, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVHBRloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVHBR, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVWBRloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVWBR, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVDBRloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AMOVDBR, + reg: regInfo{ + inputs: []inputInfo{ + {1, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 1073733624}, // R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "FMOVDloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AFMOVD, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 576460743713488896}, // F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 + }, + }, + }, + { + name: "FMOVSloadidx", + auxType: auxSymOff, + argLen: 3, + faultOnNilArg0: true, + symEffect: SymRead, + asm: ppc64.AFMOVS, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + outputs: []outputInfo{ + {0, 576460743713488896}, // F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 + }, + }, + }, + { name: "MOVDBRstore", auxType: auxSymOff, argLen: 3, @@ -21849,6 +22512,141 @@ var opcodeTable = [...]opInfo{ }, }, { + name: "MOVBstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AMOVB, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {2, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVHstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AMOVH, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {2, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVWstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AMOVW, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {2, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVDstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AMOVD, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {2, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "FMOVDstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AFMOVD, + reg: regInfo{ + inputs: []inputInfo{ + {2, 576460743713488896}, // F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "FMOVSstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AFMOVS, + reg: regInfo{ + inputs: []inputInfo{ + {2, 576460743713488896}, // F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14 F15 F16 F17 F18 F19 F20 F21 F22 F23 F24 F25 F26 + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVHBRstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AMOVHBR, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {2, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVWBRstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AMOVWBR, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {2, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { + name: "MOVDBRstoreidx", + auxType: auxSymOff, + argLen: 4, + faultOnNilArg0: true, + symEffect: SymWrite, + asm: ppc64.AMOVDBR, + reg: regInfo{ + inputs: []inputInfo{ + {0, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {1, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + {2, 1073733630}, // SP SB R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 + }, + }, + }, + { name: "MOVBstorezero", auxType: auxSymOff, argLen: 2, diff --git a/src/cmd/compile/internal/ssa/prove.go b/src/cmd/compile/internal/ssa/prove.go index af2b9ef0ed..6462370d5c 100644 --- a/src/cmd/compile/internal/ssa/prove.go +++ b/src/cmd/compile/internal/ssa/prove.go @@ -58,7 +58,7 @@ func (r relation) String() string { } // domain represents the domain of a variable pair in which a set -// of relations is known. For example, relations learned for unsigned +// of relations is known. For example, relations learned for unsigned // pairs cannot be transferred to signed pairs because the same bit // representation can mean something else. type domain uint @@ -625,7 +625,7 @@ var ( // For example: // OpLess8: {signed, lt}, // v1 = (OpLess8 v2 v3). - // If v1 branch is taken than we learn that the rangeMaks + // If v1 branch is taken then we learn that the rangeMask // can be at most lt. domainRelationTable = map[Op]struct { d domain diff --git a/src/cmd/compile/internal/ssa/regalloc.go b/src/cmd/compile/internal/ssa/regalloc.go index 278da6fe99..8946cf6b5c 100644 --- a/src/cmd/compile/internal/ssa/regalloc.go +++ b/src/cmd/compile/internal/ssa/regalloc.go @@ -150,6 +150,8 @@ type register uint8 const noRegister register = 255 +// A regMask encodes a set of machine registers. +// TODO: regMask -> regSet? type regMask uint64 func (m regMask) String() string { diff --git a/src/cmd/compile/internal/ssa/rewrite.go b/src/cmd/compile/internal/ssa/rewrite.go index ca6280deb1..fd5f684eda 100644 --- a/src/cmd/compile/internal/ssa/rewrite.go +++ b/src/cmd/compile/internal/ssa/rewrite.go @@ -234,7 +234,6 @@ func canMergeLoad(target, load, x *Value) bool { // memPreds contains memory states known to be predecessors of load's // memory state. It is lazily initialized. var memPreds map[*Value]bool -search: for i := 0; len(args) > 0; i++ { const limit = 100 if i >= limit { @@ -246,13 +245,13 @@ search: if target.Block.ID != v.Block.ID { // Since target and load are in the same block // we can stop searching when we leave the block. - continue search + continue } if v.Op == OpPhi { // A Phi implies we have reached the top of the block. // The memory phi, if it exists, is always // the first logical store in the block. - continue search + continue } if v.Type.IsTuple() && v.Type.FieldType(1).IsMemory() { // We could handle this situation however it is likely @@ -296,14 +295,14 @@ search: // load = read ... mem // target = add x load if memPreds[v] { - continue search + continue } return false } if len(v.Args) > 0 && v.Args[len(v.Args)-1] == mem { // If v takes mem as an input then we know mem // is valid at this point. - continue search + continue } for _, a := range v.Args { if target.Block.ID == a.Block.ID { @@ -450,19 +449,24 @@ func extend32Fto64F(f float32) float64 { return math.Float64frombits(r) } -// i2f is used in rules for converting from an AuxInt to a float. -func i2f(i int64) float64 { - return math.Float64frombits(uint64(i)) +// auxFrom64F encodes a float64 value so it can be stored in an AuxInt. +func auxFrom64F(f float64) int64 { + return int64(math.Float64bits(f)) } -// i2f32 is used in rules for converting from an AuxInt to a float32. -func i2f32(i int64) float32 { - return float32(math.Float64frombits(uint64(i))) +// auxFrom32F encodes a float32 value so it can be stored in an AuxInt. +func auxFrom32F(f float32) int64 { + return int64(math.Float64bits(extend32Fto64F(f))) } -// f2i is used in the rules for storing a float in AuxInt. -func f2i(f float64) int64 { - return int64(math.Float64bits(f)) +// auxTo32F decodes a float32 from the AuxInt value provided. +func auxTo32F(i int64) float32 { + return truncate64Fto32F(math.Float64frombits(uint64(i))) +} + +// auxTo64F decodes a float64 from the AuxInt value provided. +func auxTo64F(i int64) float64 { + return math.Float64frombits(uint64(i)) } // uaddOvf returns true if unsigned a+b would overflow. @@ -646,11 +650,11 @@ func noteRule(s string) bool { return true } -// warnRule generates a compiler debug output with string s when -// cond is true and the rule is fired. +// warnRule generates compiler debug output with string s when +// v is not in autogenerated code, cond is true and the rule has fired. func warnRule(cond bool, v *Value, s string) bool { - if cond { - v.Block.Func.Warnl(v.Pos, s) + if pos := v.Pos; pos.Line() > 1 && cond { + v.Block.Func.Warnl(pos, s) } return true } diff --git a/src/cmd/compile/internal/ssa/rewrite386.go b/src/cmd/compile/internal/ssa/rewrite386.go index abc1d18309..5481b4e773 100644 --- a/src/cmd/compile/internal/ssa/rewrite386.go +++ b/src/cmd/compile/internal/ssa/rewrite386.go @@ -2507,38 +2507,44 @@ func rewriteValue386_Op386CMPBconst_0(v *Value) bool { v.reset(Op386FlagLT_ULT) return true } - // match: (CMPBconst (ANDL x y) [0]) - // cond: + // match: (CMPBconst l:(ANDL x y) [0]) + // cond: l.Uses==1 // result: (TESTB x y) for { if v.AuxInt != 0 { break } - v_0 := v.Args[0] - if v_0.Op != Op386ANDL { + l := v.Args[0] + if l.Op != Op386ANDL { + break + } + _ = l.Args[1] + x := l.Args[0] + y := l.Args[1] + if !(l.Uses == 1) { break } - _ = v_0.Args[1] - x := v_0.Args[0] - y := v_0.Args[1] v.reset(Op386TESTB) v.AddArg(x) v.AddArg(y) return true } - // match: (CMPBconst (ANDLconst [c] x) [0]) - // cond: + // match: (CMPBconst l:(ANDLconst [c] x) [0]) + // cond: l.Uses==1 // result: (TESTBconst [int64(int8(c))] x) for { if v.AuxInt != 0 { break } - v_0 := v.Args[0] - if v_0.Op != Op386ANDLconst { + l := v.Args[0] + if l.Op != Op386ANDLconst { + break + } + c := l.AuxInt + x := l.Args[0] + if !(l.Uses == 1) { break } - c := v_0.AuxInt - x := v_0.Args[0] v.reset(Op386TESTBconst) v.AuxInt = int64(int8(c)) v.AddArg(x) @@ -2819,38 +2825,44 @@ func rewriteValue386_Op386CMPLconst_0(v *Value) bool { v.reset(Op386FlagLT_ULT) return true } - // match: (CMPLconst (ANDL x y) [0]) - // cond: + // match: (CMPLconst l:(ANDL x y) [0]) + // cond: l.Uses==1 // result: (TESTL x y) for { if v.AuxInt != 0 { break } - v_0 := v.Args[0] - if v_0.Op != Op386ANDL { + l := v.Args[0] + if l.Op != Op386ANDL { + break + } + _ = l.Args[1] + x := l.Args[0] + y := l.Args[1] + if !(l.Uses == 1) { break } - _ = v_0.Args[1] - x := v_0.Args[0] - y := v_0.Args[1] v.reset(Op386TESTL) v.AddArg(x) v.AddArg(y) return true } - // match: (CMPLconst (ANDLconst [c] x) [0]) - // cond: + // match: (CMPLconst l:(ANDLconst [c] x) [0]) + // cond: l.Uses==1 // result: (TESTLconst [c] x) for { if v.AuxInt != 0 { break } - v_0 := v.Args[0] - if v_0.Op != Op386ANDLconst { + l := v.Args[0] + if l.Op != Op386ANDLconst { + break + } + c := l.AuxInt + x := l.Args[0] + if !(l.Uses == 1) { break } - c := v_0.AuxInt - x := v_0.Args[0] v.reset(Op386TESTLconst) v.AuxInt = c v.AddArg(x) @@ -3122,38 +3134,44 @@ func rewriteValue386_Op386CMPWconst_0(v *Value) bool { v.reset(Op386FlagLT_ULT) return true } - // match: (CMPWconst (ANDL x y) [0]) - // cond: + // match: (CMPWconst l:(ANDL x y) [0]) + // cond: l.Uses==1 // result: (TESTW x y) for { if v.AuxInt != 0 { break } - v_0 := v.Args[0] - if v_0.Op != Op386ANDL { + l := v.Args[0] + if l.Op != Op386ANDL { + break + } + _ = l.Args[1] + x := l.Args[0] + y := l.Args[1] + if !(l.Uses == 1) { break } - _ = v_0.Args[1] - x := v_0.Args[0] - y := v_0.Args[1] v.reset(Op386TESTW) v.AddArg(x) v.AddArg(y) return true } - // match: (CMPWconst (ANDLconst [c] x) [0]) - // cond: + // match: (CMPWconst l:(ANDLconst [c] x) [0]) + // cond: l.Uses==1 // result: (TESTWconst [int64(int16(c))] x) for { if v.AuxInt != 0 { break } - v_0 := v.Args[0] - if v_0.Op != Op386ANDLconst { + l := v.Args[0] + if l.Op != Op386ANDLconst { + break + } + c := l.AuxInt + x := l.Args[0] + if !(l.Uses == 1) { break } - c := v_0.AuxInt - x := v_0.Args[0] v.reset(Op386TESTWconst) v.AuxInt = int64(int16(c)) v.AddArg(x) @@ -19804,7 +19822,7 @@ func rewriteValue386_OpNeg32F_0(v *Value) bool { _ = typ // match: (Neg32F x) // cond: !config.use387 - // result: (PXOR x (MOVSSconst <typ.Float32> [f2i(math.Copysign(0, -1))])) + // result: (PXOR x (MOVSSconst <typ.Float32> [auxFrom32F(float32(math.Copysign(0, -1)))])) for { x := v.Args[0] if !(!config.use387) { @@ -19813,7 +19831,7 @@ func rewriteValue386_OpNeg32F_0(v *Value) bool { v.reset(Op386PXOR) v.AddArg(x) v0 := b.NewValue0(v.Pos, Op386MOVSSconst, typ.Float32) - v0.AuxInt = f2i(math.Copysign(0, -1)) + v0.AuxInt = auxFrom32F(float32(math.Copysign(0, -1))) v.AddArg(v0) return true } @@ -19840,7 +19858,7 @@ func rewriteValue386_OpNeg64F_0(v *Value) bool { _ = typ // match: (Neg64F x) // cond: !config.use387 - // result: (PXOR x (MOVSDconst <typ.Float64> [f2i(math.Copysign(0, -1))])) + // result: (PXOR x (MOVSDconst <typ.Float64> [auxFrom64F(math.Copysign(0, -1))])) for { x := v.Args[0] if !(!config.use387) { @@ -19849,7 +19867,7 @@ func rewriteValue386_OpNeg64F_0(v *Value) bool { v.reset(Op386PXOR) v.AddArg(x) v0 := b.NewValue0(v.Pos, Op386MOVSDconst, typ.Float64) - v0.AuxInt = f2i(math.Copysign(0, -1)) + v0.AuxInt = auxFrom64F(math.Copysign(0, -1)) v.AddArg(v0) return true } diff --git a/src/cmd/compile/internal/ssa/rewriteAMD64.go b/src/cmd/compile/internal/ssa/rewriteAMD64.go index 1b531954db..89fc6780b9 100644 --- a/src/cmd/compile/internal/ssa/rewriteAMD64.go +++ b/src/cmd/compile/internal/ssa/rewriteAMD64.go @@ -65,18 +65,46 @@ func rewriteValueAMD64(v *Value) bool { return rewriteValueAMD64_OpAMD64ANDQmodify_0(v) case OpAMD64BSFQ: return rewriteValueAMD64_OpAMD64BSFQ_0(v) + case OpAMD64BTCLconst: + return rewriteValueAMD64_OpAMD64BTCLconst_0(v) + case OpAMD64BTCLconstmodify: + return rewriteValueAMD64_OpAMD64BTCLconstmodify_0(v) + case OpAMD64BTCLmodify: + return rewriteValueAMD64_OpAMD64BTCLmodify_0(v) + case OpAMD64BTCQconst: + return rewriteValueAMD64_OpAMD64BTCQconst_0(v) + case OpAMD64BTCQconstmodify: + return rewriteValueAMD64_OpAMD64BTCQconstmodify_0(v) + case OpAMD64BTCQmodify: + return rewriteValueAMD64_OpAMD64BTCQmodify_0(v) case OpAMD64BTLconst: return rewriteValueAMD64_OpAMD64BTLconst_0(v) case OpAMD64BTQconst: return rewriteValueAMD64_OpAMD64BTQconst_0(v) case OpAMD64BTRLconst: return rewriteValueAMD64_OpAMD64BTRLconst_0(v) + case OpAMD64BTRLconstmodify: + return rewriteValueAMD64_OpAMD64BTRLconstmodify_0(v) + case OpAMD64BTRLmodify: + return rewriteValueAMD64_OpAMD64BTRLmodify_0(v) case OpAMD64BTRQconst: return rewriteValueAMD64_OpAMD64BTRQconst_0(v) + case OpAMD64BTRQconstmodify: + return rewriteValueAMD64_OpAMD64BTRQconstmodify_0(v) + case OpAMD64BTRQmodify: + return rewriteValueAMD64_OpAMD64BTRQmodify_0(v) case OpAMD64BTSLconst: return rewriteValueAMD64_OpAMD64BTSLconst_0(v) + case OpAMD64BTSLconstmodify: + return rewriteValueAMD64_OpAMD64BTSLconstmodify_0(v) + case OpAMD64BTSLmodify: + return rewriteValueAMD64_OpAMD64BTSLmodify_0(v) case OpAMD64BTSQconst: return rewriteValueAMD64_OpAMD64BTSQconst_0(v) + case OpAMD64BTSQconstmodify: + return rewriteValueAMD64_OpAMD64BTSQconstmodify_0(v) + case OpAMD64BTSQmodify: + return rewriteValueAMD64_OpAMD64BTSQmodify_0(v) case OpAMD64CMOVLCC: return rewriteValueAMD64_OpAMD64CMOVLCC_0(v) case OpAMD64CMOVLCS: @@ -141,24 +169,32 @@ func rewriteValueAMD64(v *Value) bool { return rewriteValueAMD64_OpAMD64CMPB_0(v) case OpAMD64CMPBconst: return rewriteValueAMD64_OpAMD64CMPBconst_0(v) + case OpAMD64CMPBconstload: + return rewriteValueAMD64_OpAMD64CMPBconstload_0(v) case OpAMD64CMPBload: return rewriteValueAMD64_OpAMD64CMPBload_0(v) case OpAMD64CMPL: return rewriteValueAMD64_OpAMD64CMPL_0(v) case OpAMD64CMPLconst: return rewriteValueAMD64_OpAMD64CMPLconst_0(v) || rewriteValueAMD64_OpAMD64CMPLconst_10(v) + case OpAMD64CMPLconstload: + return rewriteValueAMD64_OpAMD64CMPLconstload_0(v) case OpAMD64CMPLload: return rewriteValueAMD64_OpAMD64CMPLload_0(v) case OpAMD64CMPQ: return rewriteValueAMD64_OpAMD64CMPQ_0(v) case OpAMD64CMPQconst: return rewriteValueAMD64_OpAMD64CMPQconst_0(v) || rewriteValueAMD64_OpAMD64CMPQconst_10(v) + case OpAMD64CMPQconstload: + return rewriteValueAMD64_OpAMD64CMPQconstload_0(v) case OpAMD64CMPQload: return rewriteValueAMD64_OpAMD64CMPQload_0(v) case OpAMD64CMPW: return rewriteValueAMD64_OpAMD64CMPW_0(v) case OpAMD64CMPWconst: return rewriteValueAMD64_OpAMD64CMPWconst_0(v) + case OpAMD64CMPWconstload: + return rewriteValueAMD64_OpAMD64CMPWconstload_0(v) case OpAMD64CMPWload: return rewriteValueAMD64_OpAMD64CMPWload_0(v) case OpAMD64CMPXCHGLlock: @@ -270,7 +306,7 @@ func rewriteValueAMD64(v *Value) bool { case OpAMD64MOVQloadidx8: return rewriteValueAMD64_OpAMD64MOVQloadidx8_0(v) case OpAMD64MOVQstore: - return rewriteValueAMD64_OpAMD64MOVQstore_0(v) || rewriteValueAMD64_OpAMD64MOVQstore_10(v) || rewriteValueAMD64_OpAMD64MOVQstore_20(v) + return rewriteValueAMD64_OpAMD64MOVQstore_0(v) || rewriteValueAMD64_OpAMD64MOVQstore_10(v) || rewriteValueAMD64_OpAMD64MOVQstore_20(v) || rewriteValueAMD64_OpAMD64MOVQstore_30(v) case OpAMD64MOVQstoreconst: return rewriteValueAMD64_OpAMD64MOVQstoreconst_0(v) case OpAMD64MOVQstoreconstidx1: @@ -3582,6 +3618,22 @@ func rewriteValueAMD64_OpAMD64ANDLconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (ANDLconst [c] (BTRLconst [d] x)) + // cond: + // result: (ANDLconst [c &^ (1<<uint32(d))] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTRLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ANDLconst) + v.AuxInt = c &^ (1 << uint32(d)) + v.AddArg(x) + return true + } // match: (ANDLconst [ 0xFF] x) // cond: // result: (MOVBQZX x) @@ -4093,6 +4145,22 @@ func rewriteValueAMD64_OpAMD64ANDQconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (ANDQconst [c] (BTRQconst [d] x)) + // cond: + // result: (ANDQconst [c &^ (1<<uint32(d))] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTRQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ANDQconst) + v.AuxInt = c &^ (1 << uint32(d)) + v.AddArg(x) + return true + } // match: (ANDQconst [ 0xFF] x) // cond: // result: (MOVBQZX x) @@ -4421,6 +4489,320 @@ func rewriteValueAMD64_OpAMD64BSFQ_0(v *Value) bool { } return false } +func rewriteValueAMD64_OpAMD64BTCLconst_0(v *Value) bool { + // match: (BTCLconst [c] (XORLconst [d] x)) + // cond: + // result: (XORLconst [d ^ 1<<uint32(c)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64XORLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64XORLconst) + v.AuxInt = d ^ 1<<uint32(c) + v.AddArg(x) + return true + } + // match: (BTCLconst [c] (BTCLconst [d] x)) + // cond: + // result: (XORLconst [1<<uint32(c) ^ 1<<uint32(d)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTCLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64XORLconst) + v.AuxInt = 1<<uint32(c) ^ 1<<uint32(d) + v.AddArg(x) + return true + } + // match: (BTCLconst [c] (MOVLconst [d])) + // cond: + // result: (MOVLconst [d^(1<<uint32(c))]) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64MOVLconst { + break + } + d := v_0.AuxInt + v.reset(OpAMD64MOVLconst) + v.AuxInt = d ^ (1 << uint32(c)) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTCLconstmodify_0(v *Value) bool { + // match: (BTCLconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (BTCLconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64BTCLconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (BTCLconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (BTCLconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTCLconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTCLmodify_0(v *Value) bool { + // match: (BTCLmodify [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (BTCLmodify [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64BTCLmodify) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (BTCLmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (BTCLmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTCLmodify) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTCQconst_0(v *Value) bool { + // match: (BTCQconst [c] (XORQconst [d] x)) + // cond: + // result: (XORQconst [d ^ 1<<uint32(c)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64XORQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64XORQconst) + v.AuxInt = d ^ 1<<uint32(c) + v.AddArg(x) + return true + } + // match: (BTCQconst [c] (BTCQconst [d] x)) + // cond: + // result: (XORQconst [1<<uint32(c) ^ 1<<uint32(d)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTCQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64XORQconst) + v.AuxInt = 1<<uint32(c) ^ 1<<uint32(d) + v.AddArg(x) + return true + } + // match: (BTCQconst [c] (MOVQconst [d])) + // cond: + // result: (MOVQconst [d^(1<<uint32(c))]) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64MOVQconst { + break + } + d := v_0.AuxInt + v.reset(OpAMD64MOVQconst) + v.AuxInt = d ^ (1 << uint32(c)) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTCQconstmodify_0(v *Value) bool { + // match: (BTCQconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (BTCQconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64BTCQconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (BTCQconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (BTCQconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTCQconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTCQmodify_0(v *Value) bool { + // match: (BTCQmodify [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (BTCQmodify [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64BTCQmodify) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (BTCQmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (BTCQmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTCQmodify) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + return false +} func rewriteValueAMD64_OpAMD64BTLconst_0(v *Value) bool { // match: (BTLconst [c] (SHRQconst [d] x)) // cond: (c+d)<64 @@ -4635,6 +5017,160 @@ func rewriteValueAMD64_OpAMD64BTRLconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (BTRLconst [c] (ANDLconst [d] x)) + // cond: + // result: (ANDLconst [d &^ (1<<uint32(c))] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64ANDLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ANDLconst) + v.AuxInt = d &^ (1 << uint32(c)) + v.AddArg(x) + return true + } + // match: (BTRLconst [c] (BTRLconst [d] x)) + // cond: + // result: (ANDLconst [^(1<<uint32(c) | 1<<uint32(d))] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTRLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ANDLconst) + v.AuxInt = ^(1<<uint32(c) | 1<<uint32(d)) + v.AddArg(x) + return true + } + // match: (BTRLconst [c] (MOVLconst [d])) + // cond: + // result: (MOVLconst [d&^(1<<uint32(c))]) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64MOVLconst { + break + } + d := v_0.AuxInt + v.reset(OpAMD64MOVLconst) + v.AuxInt = d &^ (1 << uint32(c)) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTRLconstmodify_0(v *Value) bool { + // match: (BTRLconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (BTRLconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64BTRLconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (BTRLconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (BTRLconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTRLconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTRLmodify_0(v *Value) bool { + // match: (BTRLmodify [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (BTRLmodify [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64BTRLmodify) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (BTRLmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (BTRLmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTRLmodify) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } return false } func rewriteValueAMD64_OpAMD64BTRQconst_0(v *Value) bool { @@ -4674,6 +5210,160 @@ func rewriteValueAMD64_OpAMD64BTRQconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (BTRQconst [c] (ANDQconst [d] x)) + // cond: + // result: (ANDQconst [d &^ (1<<uint32(c))] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64ANDQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ANDQconst) + v.AuxInt = d &^ (1 << uint32(c)) + v.AddArg(x) + return true + } + // match: (BTRQconst [c] (BTRQconst [d] x)) + // cond: + // result: (ANDQconst [^(1<<uint32(c) | 1<<uint32(d))] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTRQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ANDQconst) + v.AuxInt = ^(1<<uint32(c) | 1<<uint32(d)) + v.AddArg(x) + return true + } + // match: (BTRQconst [c] (MOVQconst [d])) + // cond: + // result: (MOVQconst [d&^(1<<uint32(c))]) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64MOVQconst { + break + } + d := v_0.AuxInt + v.reset(OpAMD64MOVQconst) + v.AuxInt = d &^ (1 << uint32(c)) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTRQconstmodify_0(v *Value) bool { + // match: (BTRQconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (BTRQconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64BTRQconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (BTRQconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (BTRQconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTRQconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTRQmodify_0(v *Value) bool { + // match: (BTRQmodify [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (BTRQmodify [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64BTRQmodify) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (BTRQmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (BTRQmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTRQmodify) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } return false } func rewriteValueAMD64_OpAMD64BTSLconst_0(v *Value) bool { @@ -4713,6 +5403,160 @@ func rewriteValueAMD64_OpAMD64BTSLconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (BTSLconst [c] (ORLconst [d] x)) + // cond: + // result: (ORLconst [d | 1<<uint32(c)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64ORLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ORLconst) + v.AuxInt = d | 1<<uint32(c) + v.AddArg(x) + return true + } + // match: (BTSLconst [c] (BTSLconst [d] x)) + // cond: + // result: (ORLconst [1<<uint32(d) | 1<<uint32(c)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTSLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ORLconst) + v.AuxInt = 1<<uint32(d) | 1<<uint32(c) + v.AddArg(x) + return true + } + // match: (BTSLconst [c] (MOVLconst [d])) + // cond: + // result: (MOVLconst [d|(1<<uint32(c))]) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64MOVLconst { + break + } + d := v_0.AuxInt + v.reset(OpAMD64MOVLconst) + v.AuxInt = d | (1 << uint32(c)) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTSLconstmodify_0(v *Value) bool { + // match: (BTSLconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (BTSLconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64BTSLconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (BTSLconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (BTSLconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTSLconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTSLmodify_0(v *Value) bool { + // match: (BTSLmodify [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (BTSLmodify [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64BTSLmodify) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (BTSLmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (BTSLmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTSLmodify) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } return false } func rewriteValueAMD64_OpAMD64BTSQconst_0(v *Value) bool { @@ -4752,6 +5596,160 @@ func rewriteValueAMD64_OpAMD64BTSQconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (BTSQconst [c] (ORQconst [d] x)) + // cond: + // result: (ORQconst [d | 1<<uint32(c)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64ORQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ORQconst) + v.AuxInt = d | 1<<uint32(c) + v.AddArg(x) + return true + } + // match: (BTSQconst [c] (BTSQconst [d] x)) + // cond: + // result: (ORQconst [1<<uint32(d) | 1<<uint32(c)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTSQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ORQconst) + v.AuxInt = 1<<uint32(d) | 1<<uint32(c) + v.AddArg(x) + return true + } + // match: (BTSQconst [c] (MOVQconst [d])) + // cond: + // result: (MOVQconst [d|(1<<uint32(c))]) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64MOVQconst { + break + } + d := v_0.AuxInt + v.reset(OpAMD64MOVQconst) + v.AuxInt = d | (1 << uint32(c)) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTSQconstmodify_0(v *Value) bool { + // match: (BTSQconstmodify [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (BTSQconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64BTSQconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (BTSQconstmodify [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (BTSQconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTSQconstmodify) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64BTSQmodify_0(v *Value) bool { + // match: (BTSQmodify [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (BTSQmodify [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64BTSQmodify) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (BTSQmodify [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (BTSQmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64BTSQmodify) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } return false } func rewriteValueAMD64_OpAMD64CMOVLCC_0(v *Value) bool { @@ -7932,7 +8930,112 @@ func rewriteValueAMD64_OpAMD64CMPBconst_0(v *Value) bool { } return false } +func rewriteValueAMD64_OpAMD64CMPBconstload_0(v *Value) bool { + // match: (CMPBconstload [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (CMPBconstload [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64CMPBconstload) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (CMPBconstload [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (CMPBconstload [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64CMPBconstload) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} func rewriteValueAMD64_OpAMD64CMPBload_0(v *Value) bool { + // match: (CMPBload [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (CMPBload [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64CMPBload) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (CMPBload [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (CMPBload [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64CMPBload) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (CMPBload {sym} [off] ptr (MOVLconst [c]) mem) // cond: validValAndOff(int64(int8(c)),off) // result: (CMPBconstload {sym} [makeValAndOff(int64(int8(c)),off)] ptr mem) @@ -8249,7 +9352,112 @@ func rewriteValueAMD64_OpAMD64CMPLconst_10(v *Value) bool { } return false } +func rewriteValueAMD64_OpAMD64CMPLconstload_0(v *Value) bool { + // match: (CMPLconstload [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (CMPLconstload [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64CMPLconstload) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (CMPLconstload [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (CMPLconstload [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64CMPLconstload) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} func rewriteValueAMD64_OpAMD64CMPLload_0(v *Value) bool { + // match: (CMPLload [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (CMPLload [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64CMPLload) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (CMPLload [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (CMPLload [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64CMPLload) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (CMPLload {sym} [off] ptr (MOVLconst [c]) mem) // cond: validValAndOff(c,off) // result: (CMPLconstload {sym} [makeValAndOff(c,off)] ptr mem) @@ -8689,7 +9897,112 @@ func rewriteValueAMD64_OpAMD64CMPQconst_10(v *Value) bool { } return false } +func rewriteValueAMD64_OpAMD64CMPQconstload_0(v *Value) bool { + // match: (CMPQconstload [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (CMPQconstload [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64CMPQconstload) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (CMPQconstload [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (CMPQconstload [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64CMPQconstload) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} func rewriteValueAMD64_OpAMD64CMPQload_0(v *Value) bool { + // match: (CMPQload [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (CMPQload [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64CMPQload) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (CMPQload [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (CMPQload [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64CMPQload) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (CMPQload {sym} [off] ptr (MOVQconst [c]) mem) // cond: validValAndOff(c,off) // result: (CMPQconstload {sym} [makeValAndOff(c,off)] ptr mem) @@ -8987,7 +10300,112 @@ func rewriteValueAMD64_OpAMD64CMPWconst_0(v *Value) bool { } return false } +func rewriteValueAMD64_OpAMD64CMPWconstload_0(v *Value) bool { + // match: (CMPWconstload [valoff1] {sym} (ADDQconst [off2] base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) + // result: (CMPWconstload [ValAndOff(valoff1).add(off2)] {sym} base mem) + for { + valoff1 := v.AuxInt + sym := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2)) { + break + } + v.reset(OpAMD64CMPWconstload) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = sym + v.AddArg(base) + v.AddArg(mem) + return true + } + // match: (CMPWconstload [valoff1] {sym1} (LEAQ [off2] {sym2} base) mem) + // cond: ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) + // result: (CMPWconstload [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem) + for { + valoff1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + mem := v.Args[1] + if !(ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64CMPWconstload) + v.AuxInt = ValAndOff(valoff1).add(off2) + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(mem) + return true + } + return false +} func rewriteValueAMD64_OpAMD64CMPWload_0(v *Value) bool { + // match: (CMPWload [off1] {sym} (ADDQconst [off2] base) val mem) + // cond: is32Bit(off1+off2) + // result: (CMPWload [off1+off2] {sym} base val mem) + for { + off1 := v.AuxInt + sym := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64ADDQconst { + break + } + off2 := v_0.AuxInt + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1 + off2)) { + break + } + v.reset(OpAMD64CMPWload) + v.AuxInt = off1 + off2 + v.Aux = sym + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (CMPWload [off1] {sym1} (LEAQ [off2] {sym2} base) val mem) + // cond: is32Bit(off1+off2) && canMergeSym(sym1, sym2) + // result: (CMPWload [off1+off2] {mergeSym(sym1,sym2)} base val mem) + for { + off1 := v.AuxInt + sym1 := v.Aux + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpAMD64LEAQ { + break + } + off2 := v_0.AuxInt + sym2 := v_0.Aux + base := v_0.Args[0] + val := v.Args[1] + mem := v.Args[2] + if !(is32Bit(off1+off2) && canMergeSym(sym1, sym2)) { + break + } + v.reset(OpAMD64CMPWload) + v.AuxInt = off1 + off2 + v.Aux = mergeSym(sym1, sym2) + v.AddArg(base) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (CMPWload {sym} [off] ptr (MOVLconst [c]) mem) // cond: validValAndOff(int64(int16(c)),off) // result: (CMPWconstload {sym} [makeValAndOff(int64(int16(c)),off)] ptr mem) @@ -15448,8 +16866,140 @@ func rewriteValueAMD64_OpAMD64MOVLstore_20(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVLstore {sym} [off] ptr y:(BTCL l:(MOVLload [off] {sym} ptr mem) x) mem) + // cond: y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) + // result: (BTCLmodify [off] {sym} ptr x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + y := v.Args[1] + if y.Op != OpAMD64BTCL { + break + } + _ = y.Args[1] + l := y.Args[0] + if l.Op != OpAMD64MOVLload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + if ptr != l.Args[0] { + break + } + mem := l.Args[1] + x := y.Args[1] + if mem != v.Args[2] { + break + } + if !(y.Uses == 1 && l.Uses == 1 && clobber(y) && clobber(l)) { + break + } + v.reset(OpAMD64BTCLmodify) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVLstore {sym} [off] ptr y:(BTRL l:(MOVLload [off] {sym} ptr mem) x) mem) + // cond: y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) + // result: (BTRLmodify [off] {sym} ptr x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + y := v.Args[1] + if y.Op != OpAMD64BTRL { + break + } + _ = y.Args[1] + l := y.Args[0] + if l.Op != OpAMD64MOVLload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + if ptr != l.Args[0] { + break + } + mem := l.Args[1] + x := y.Args[1] + if mem != v.Args[2] { + break + } + if !(y.Uses == 1 && l.Uses == 1 && clobber(y) && clobber(l)) { + break + } + v.reset(OpAMD64BTRLmodify) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVLstore {sym} [off] ptr y:(BTSL l:(MOVLload [off] {sym} ptr mem) x) mem) + // cond: y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) + // result: (BTSLmodify [off] {sym} ptr x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + y := v.Args[1] + if y.Op != OpAMD64BTSL { + break + } + _ = y.Args[1] + l := y.Args[0] + if l.Op != OpAMD64MOVLload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + if ptr != l.Args[0] { + break + } + mem := l.Args[1] + x := y.Args[1] + if mem != v.Args[2] { + break + } + if !(y.Uses == 1 && l.Uses == 1 && clobber(y) && clobber(l)) { + break + } + v.reset(OpAMD64BTSLmodify) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(x) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64MOVLstore_30(v *Value) bool { // match: (MOVLstore [off] {sym} ptr a:(ADDLconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) - // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) // result: (ADDLconstmodify {sym} [makeValAndOff(c,off)] ptr mem) for { off := v.AuxInt @@ -15477,7 +17027,7 @@ func rewriteValueAMD64_OpAMD64MOVLstore_20(v *Value) bool { if mem != v.Args[2] { break } - if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off)) { + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { break } v.reset(OpAMD64ADDLconstmodify) @@ -15488,7 +17038,7 @@ func rewriteValueAMD64_OpAMD64MOVLstore_20(v *Value) bool { return true } // match: (MOVLstore [off] {sym} ptr a:(ANDLconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) - // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) // result: (ANDLconstmodify {sym} [makeValAndOff(c,off)] ptr mem) for { off := v.AuxInt @@ -15516,7 +17066,7 @@ func rewriteValueAMD64_OpAMD64MOVLstore_20(v *Value) bool { if mem != v.Args[2] { break } - if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off)) { + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { break } v.reset(OpAMD64ANDLconstmodify) @@ -15527,7 +17077,7 @@ func rewriteValueAMD64_OpAMD64MOVLstore_20(v *Value) bool { return true } // match: (MOVLstore [off] {sym} ptr a:(ORLconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) - // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) // result: (ORLconstmodify {sym} [makeValAndOff(c,off)] ptr mem) for { off := v.AuxInt @@ -15555,7 +17105,7 @@ func rewriteValueAMD64_OpAMD64MOVLstore_20(v *Value) bool { if mem != v.Args[2] { break } - if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off)) { + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { break } v.reset(OpAMD64ORLconstmodify) @@ -15565,11 +17115,8 @@ func rewriteValueAMD64_OpAMD64MOVLstore_20(v *Value) bool { v.AddArg(mem) return true } - return false -} -func rewriteValueAMD64_OpAMD64MOVLstore_30(v *Value) bool { // match: (MOVLstore [off] {sym} ptr a:(XORLconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) - // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) // result: (XORLconstmodify {sym} [makeValAndOff(c,off)] ptr mem) for { off := v.AuxInt @@ -15597,7 +17144,7 @@ func rewriteValueAMD64_OpAMD64MOVLstore_30(v *Value) bool { if mem != v.Args[2] { break } - if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off)) { + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { break } v.reset(OpAMD64XORLconstmodify) @@ -15607,6 +17154,123 @@ func rewriteValueAMD64_OpAMD64MOVLstore_30(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVLstore [off] {sym} ptr a:(BTCLconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) + // result: (BTCLconstmodify {sym} [makeValAndOff(c,off)] ptr mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + a := v.Args[1] + if a.Op != OpAMD64BTCLconst { + break + } + c := a.AuxInt + l := a.Args[0] + if l.Op != OpAMD64MOVLload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + ptr2 := l.Args[0] + mem := l.Args[1] + if mem != v.Args[2] { + break + } + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { + break + } + v.reset(OpAMD64BTCLconstmodify) + v.AuxInt = makeValAndOff(c, off) + v.Aux = sym + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVLstore [off] {sym} ptr a:(BTRLconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) + // result: (BTRLconstmodify {sym} [makeValAndOff(c,off)] ptr mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + a := v.Args[1] + if a.Op != OpAMD64BTRLconst { + break + } + c := a.AuxInt + l := a.Args[0] + if l.Op != OpAMD64MOVLload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + ptr2 := l.Args[0] + mem := l.Args[1] + if mem != v.Args[2] { + break + } + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { + break + } + v.reset(OpAMD64BTRLconstmodify) + v.AuxInt = makeValAndOff(c, off) + v.Aux = sym + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVLstore [off] {sym} ptr a:(BTSLconst [c] l:(MOVLload [off] {sym} ptr2 mem)) mem) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) + // result: (BTSLconstmodify {sym} [makeValAndOff(c,off)] ptr mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + a := v.Args[1] + if a.Op != OpAMD64BTSLconst { + break + } + c := a.AuxInt + l := a.Args[0] + if l.Op != OpAMD64MOVLload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + ptr2 := l.Args[0] + mem := l.Args[1] + if mem != v.Args[2] { + break + } + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { + break + } + v.reset(OpAMD64BTSLconstmodify) + v.AuxInt = makeValAndOff(c, off) + v.Aux = sym + v.AddArg(ptr) + v.AddArg(mem) + return true + } // match: (MOVLstore [off] {sym} ptr (MOVLf2i val) mem) // cond: // result: (MOVSSstore [off] {sym} ptr val mem) @@ -18099,8 +19763,137 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVQstore {sym} [off] ptr y:(BTCQ l:(MOVQload [off] {sym} ptr mem) x) mem) + // cond: y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) + // result: (BTCQmodify [off] {sym} ptr x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + y := v.Args[1] + if y.Op != OpAMD64BTCQ { + break + } + _ = y.Args[1] + l := y.Args[0] + if l.Op != OpAMD64MOVQload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + if ptr != l.Args[0] { + break + } + mem := l.Args[1] + x := y.Args[1] + if mem != v.Args[2] { + break + } + if !(y.Uses == 1 && l.Uses == 1 && clobber(y) && clobber(l)) { + break + } + v.reset(OpAMD64BTCQmodify) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVQstore {sym} [off] ptr y:(BTRQ l:(MOVQload [off] {sym} ptr mem) x) mem) + // cond: y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) + // result: (BTRQmodify [off] {sym} ptr x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + y := v.Args[1] + if y.Op != OpAMD64BTRQ { + break + } + _ = y.Args[1] + l := y.Args[0] + if l.Op != OpAMD64MOVQload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + if ptr != l.Args[0] { + break + } + mem := l.Args[1] + x := y.Args[1] + if mem != v.Args[2] { + break + } + if !(y.Uses == 1 && l.Uses == 1 && clobber(y) && clobber(l)) { + break + } + v.reset(OpAMD64BTRQmodify) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVQstore {sym} [off] ptr y:(BTSQ l:(MOVQload [off] {sym} ptr mem) x) mem) + // cond: y.Uses==1 && l.Uses==1 && clobber(y) && clobber(l) + // result: (BTSQmodify [off] {sym} ptr x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + y := v.Args[1] + if y.Op != OpAMD64BTSQ { + break + } + _ = y.Args[1] + l := y.Args[0] + if l.Op != OpAMD64MOVQload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + if ptr != l.Args[0] { + break + } + mem := l.Args[1] + x := y.Args[1] + if mem != v.Args[2] { + break + } + if !(y.Uses == 1 && l.Uses == 1 && clobber(y) && clobber(l)) { + break + } + v.reset(OpAMD64BTSQmodify) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(x) + v.AddArg(mem) + return true + } // match: (MOVQstore [off] {sym} ptr a:(ADDQconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) - // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) // result: (ADDQconstmodify {sym} [makeValAndOff(c,off)] ptr mem) for { off := v.AuxInt @@ -18128,7 +19921,7 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { if mem != v.Args[2] { break } - if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off)) { + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { break } v.reset(OpAMD64ADDQconstmodify) @@ -18139,7 +19932,7 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { return true } // match: (MOVQstore [off] {sym} ptr a:(ANDQconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) - // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) // result: (ANDQconstmodify {sym} [makeValAndOff(c,off)] ptr mem) for { off := v.AuxInt @@ -18167,7 +19960,7 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { if mem != v.Args[2] { break } - if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off)) { + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { break } v.reset(OpAMD64ANDQconstmodify) @@ -18178,7 +19971,7 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { return true } // match: (MOVQstore [off] {sym} ptr a:(ORQconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) - // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) // result: (ORQconstmodify {sym} [makeValAndOff(c,off)] ptr mem) for { off := v.AuxInt @@ -18206,7 +19999,7 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { if mem != v.Args[2] { break } - if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off)) { + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { break } v.reset(OpAMD64ORQconstmodify) @@ -18217,7 +20010,7 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { return true } // match: (MOVQstore [off] {sym} ptr a:(XORQconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) - // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) // result: (XORQconstmodify {sym} [makeValAndOff(c,off)] ptr mem) for { off := v.AuxInt @@ -18245,7 +20038,7 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { if mem != v.Args[2] { break } - if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off)) { + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { break } v.reset(OpAMD64XORQconstmodify) @@ -18255,6 +20048,126 @@ func rewriteValueAMD64_OpAMD64MOVQstore_20(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVQstore [off] {sym} ptr a:(BTCQconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) + // result: (BTCQconstmodify {sym} [makeValAndOff(c,off)] ptr mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + a := v.Args[1] + if a.Op != OpAMD64BTCQconst { + break + } + c := a.AuxInt + l := a.Args[0] + if l.Op != OpAMD64MOVQload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + ptr2 := l.Args[0] + mem := l.Args[1] + if mem != v.Args[2] { + break + } + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { + break + } + v.reset(OpAMD64BTCQconstmodify) + v.AuxInt = makeValAndOff(c, off) + v.Aux = sym + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVQstore [off] {sym} ptr a:(BTRQconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) + // result: (BTRQconstmodify {sym} [makeValAndOff(c,off)] ptr mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + a := v.Args[1] + if a.Op != OpAMD64BTRQconst { + break + } + c := a.AuxInt + l := a.Args[0] + if l.Op != OpAMD64MOVQload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + ptr2 := l.Args[0] + mem := l.Args[1] + if mem != v.Args[2] { + break + } + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { + break + } + v.reset(OpAMD64BTRQconstmodify) + v.AuxInt = makeValAndOff(c, off) + v.Aux = sym + v.AddArg(ptr) + v.AddArg(mem) + return true + } + return false +} +func rewriteValueAMD64_OpAMD64MOVQstore_30(v *Value) bool { + // match: (MOVQstore [off] {sym} ptr a:(BTSQconst [c] l:(MOVQload [off] {sym} ptr2 mem)) mem) + // cond: isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c,off) && clobber(l) && clobber(a) + // result: (BTSQconstmodify {sym} [makeValAndOff(c,off)] ptr mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + a := v.Args[1] + if a.Op != OpAMD64BTSQconst { + break + } + c := a.AuxInt + l := a.Args[0] + if l.Op != OpAMD64MOVQload { + break + } + if l.AuxInt != off { + break + } + if l.Aux != sym { + break + } + _ = l.Args[1] + ptr2 := l.Args[0] + mem := l.Args[1] + if mem != v.Args[2] { + break + } + if !(isSamePtr(ptr, ptr2) && a.Uses == 1 && l.Uses == 1 && validValAndOff(c, off) && clobber(l) && clobber(a)) { + break + } + v.reset(OpAMD64BTSQconstmodify) + v.AuxInt = makeValAndOff(c, off) + v.Aux = sym + v.AddArg(ptr) + v.AddArg(mem) + return true + } // match: (MOVQstore [off] {sym} ptr (MOVQf2i val) mem) // cond: // result: (MOVSDstore [off] {sym} ptr val mem) @@ -32713,6 +34626,38 @@ func rewriteValueAMD64_OpAMD64ORLconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (ORLconst [c] (ORLconst [d] x)) + // cond: + // result: (ORLconst [c | d] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64ORLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ORLconst) + v.AuxInt = c | d + v.AddArg(x) + return true + } + // match: (ORLconst [c] (BTSLconst [d] x)) + // cond: + // result: (ORLconst [c | 1<<uint32(d)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTSLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ORLconst) + v.AuxInt = c | 1<<uint32(d) + v.AddArg(x) + return true + } // match: (ORLconst [c] x) // cond: int32(c)==0 // result: x @@ -43732,6 +45677,38 @@ func rewriteValueAMD64_OpAMD64ORQconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (ORQconst [c] (ORQconst [d] x)) + // cond: + // result: (ORQconst [c | d] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64ORQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ORQconst) + v.AuxInt = c | d + v.AddArg(x) + return true + } + // match: (ORQconst [c] (BTSQconst [d] x)) + // cond: + // result: (ORQconst [c | 1<<uint32(d)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTSQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64ORQconst) + v.AuxInt = c | 1<<uint32(d) + v.AddArg(x) + return true + } // match: (ORQconst [0] x) // cond: // result: x @@ -54458,6 +56435,22 @@ func rewriteValueAMD64_OpAMD64XORLconst_10(v *Value) bool { v.AddArg(x) return true } + // match: (XORLconst [c] (BTCLconst [d] x)) + // cond: + // result: (XORLconst [c ^ 1<<uint32(d)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTCLconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64XORLconst) + v.AuxInt = c ^ 1<<uint32(d) + v.AddArg(x) + return true + } // match: (XORLconst [c] x) // cond: int32(c)==0 // result: x @@ -54981,6 +56974,22 @@ func rewriteValueAMD64_OpAMD64XORQconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (XORQconst [c] (BTCQconst [d] x)) + // cond: + // result: (XORQconst [c ^ 1<<uint32(d)] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpAMD64BTCQconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpAMD64XORQconst) + v.AuxInt = c ^ 1<<uint32(d) + v.AddArg(x) + return true + } // match: (XORQconst [0] x) // cond: // result: x @@ -60410,13 +62419,13 @@ func rewriteValueAMD64_OpNeg32F_0(v *Value) bool { _ = typ // match: (Neg32F x) // cond: - // result: (PXOR x (MOVSSconst <typ.Float32> [f2i(math.Copysign(0, -1))])) + // result: (PXOR x (MOVSSconst <typ.Float32> [auxFrom32F(float32(math.Copysign(0, -1)))])) for { x := v.Args[0] v.reset(OpAMD64PXOR) v.AddArg(x) v0 := b.NewValue0(v.Pos, OpAMD64MOVSSconst, typ.Float32) - v0.AuxInt = f2i(math.Copysign(0, -1)) + v0.AuxInt = auxFrom32F(float32(math.Copysign(0, -1))) v.AddArg(v0) return true } @@ -60439,13 +62448,13 @@ func rewriteValueAMD64_OpNeg64F_0(v *Value) bool { _ = typ // match: (Neg64F x) // cond: - // result: (PXOR x (MOVSDconst <typ.Float64> [f2i(math.Copysign(0, -1))])) + // result: (PXOR x (MOVSDconst <typ.Float64> [auxFrom64F(math.Copysign(0, -1))])) for { x := v.Args[0] v.reset(OpAMD64PXOR) v.AddArg(x) v0 := b.NewValue0(v.Pos, OpAMD64MOVSDconst, typ.Float64) - v0.AuxInt = f2i(math.Copysign(0, -1)) + v0.AuxInt = auxFrom64F(math.Copysign(0, -1)) v.AddArg(v0) return true } diff --git a/src/cmd/compile/internal/ssa/rewriteARM64.go b/src/cmd/compile/internal/ssa/rewriteARM64.go index fbdf352998..ba38ae0505 100644 --- a/src/cmd/compile/internal/ssa/rewriteARM64.go +++ b/src/cmd/compile/internal/ssa/rewriteARM64.go @@ -16,7 +16,7 @@ var _ = types.TypeMem // in case not otherwise used func rewriteValueARM64(v *Value) bool { switch v.Op { case OpARM64ADD: - return rewriteValueARM64_OpARM64ADD_0(v) || rewriteValueARM64_OpARM64ADD_10(v) + return rewriteValueARM64_OpARM64ADD_0(v) || rewriteValueARM64_OpARM64ADD_10(v) || rewriteValueARM64_OpARM64ADD_20(v) case OpARM64ADDconst: return rewriteValueARM64_OpARM64ADDconst_0(v) case OpARM64ADDshiftLL: @@ -51,6 +51,12 @@ func rewriteValueARM64(v *Value) bool { return rewriteValueARM64_OpARM64CMNWconst_0(v) case OpARM64CMNconst: return rewriteValueARM64_OpARM64CMNconst_0(v) + case OpARM64CMNshiftLL: + return rewriteValueARM64_OpARM64CMNshiftLL_0(v) + case OpARM64CMNshiftRA: + return rewriteValueARM64_OpARM64CMNshiftRA_0(v) + case OpARM64CMNshiftRL: + return rewriteValueARM64_OpARM64CMNshiftRL_0(v) case OpARM64CMP: return rewriteValueARM64_OpARM64CMP_0(v) case OpARM64CMPW: @@ -87,6 +93,8 @@ func rewriteValueARM64(v *Value) bool { return rewriteValueARM64_OpARM64FADDD_0(v) case OpARM64FADDS: return rewriteValueARM64_OpARM64FADDS_0(v) + case OpARM64FMOVDfpgp: + return rewriteValueARM64_OpARM64FMOVDfpgp_0(v) case OpARM64FMOVDgpfp: return rewriteValueARM64_OpARM64FMOVDgpfp_0(v) case OpARM64FMOVDload: @@ -137,6 +145,10 @@ func rewriteValueARM64(v *Value) bool { return rewriteValueARM64_OpARM64LessThan_0(v) case OpARM64LessThanU: return rewriteValueARM64_OpARM64LessThanU_0(v) + case OpARM64MADD: + return rewriteValueARM64_OpARM64MADD_0(v) || rewriteValueARM64_OpARM64MADD_10(v) || rewriteValueARM64_OpARM64MADD_20(v) + case OpARM64MADDW: + return rewriteValueARM64_OpARM64MADDW_0(v) || rewriteValueARM64_OpARM64MADDW_10(v) || rewriteValueARM64_OpARM64MADDW_20(v) case OpARM64MNEG: return rewriteValueARM64_OpARM64MNEG_0(v) || rewriteValueARM64_OpARM64MNEG_10(v) || rewriteValueARM64_OpARM64MNEG_20(v) case OpARM64MNEGW: @@ -243,18 +255,34 @@ func rewriteValueARM64(v *Value) bool { return rewriteValueARM64_OpARM64MOVWstorezeroidx_0(v) case OpARM64MOVWstorezeroidx4: return rewriteValueARM64_OpARM64MOVWstorezeroidx4_0(v) + case OpARM64MSUB: + return rewriteValueARM64_OpARM64MSUB_0(v) || rewriteValueARM64_OpARM64MSUB_10(v) || rewriteValueARM64_OpARM64MSUB_20(v) + case OpARM64MSUBW: + return rewriteValueARM64_OpARM64MSUBW_0(v) || rewriteValueARM64_OpARM64MSUBW_10(v) || rewriteValueARM64_OpARM64MSUBW_20(v) case OpARM64MUL: return rewriteValueARM64_OpARM64MUL_0(v) || rewriteValueARM64_OpARM64MUL_10(v) || rewriteValueARM64_OpARM64MUL_20(v) case OpARM64MULW: return rewriteValueARM64_OpARM64MULW_0(v) || rewriteValueARM64_OpARM64MULW_10(v) || rewriteValueARM64_OpARM64MULW_20(v) case OpARM64MVN: return rewriteValueARM64_OpARM64MVN_0(v) + case OpARM64MVNshiftLL: + return rewriteValueARM64_OpARM64MVNshiftLL_0(v) + case OpARM64MVNshiftRA: + return rewriteValueARM64_OpARM64MVNshiftRA_0(v) + case OpARM64MVNshiftRL: + return rewriteValueARM64_OpARM64MVNshiftRL_0(v) case OpARM64NEG: return rewriteValueARM64_OpARM64NEG_0(v) + case OpARM64NEGshiftLL: + return rewriteValueARM64_OpARM64NEGshiftLL_0(v) + case OpARM64NEGshiftRA: + return rewriteValueARM64_OpARM64NEGshiftRA_0(v) + case OpARM64NEGshiftRL: + return rewriteValueARM64_OpARM64NEGshiftRL_0(v) case OpARM64NotEqual: return rewriteValueARM64_OpARM64NotEqual_0(v) case OpARM64OR: - return rewriteValueARM64_OpARM64OR_0(v) || rewriteValueARM64_OpARM64OR_10(v) || rewriteValueARM64_OpARM64OR_20(v) || rewriteValueARM64_OpARM64OR_30(v) + return rewriteValueARM64_OpARM64OR_0(v) || rewriteValueARM64_OpARM64OR_10(v) || rewriteValueARM64_OpARM64OR_20(v) || rewriteValueARM64_OpARM64OR_30(v) || rewriteValueARM64_OpARM64OR_40(v) case OpARM64ORN: return rewriteValueARM64_OpARM64ORN_0(v) case OpARM64ORNshiftLL: @@ -271,6 +299,10 @@ func rewriteValueARM64(v *Value) bool { return rewriteValueARM64_OpARM64ORshiftRA_0(v) case OpARM64ORshiftRL: return rewriteValueARM64_OpARM64ORshiftRL_0(v) + case OpARM64RORWconst: + return rewriteValueARM64_OpARM64RORWconst_0(v) + case OpARM64RORconst: + return rewriteValueARM64_OpARM64RORconst_0(v) case OpARM64SLL: return rewriteValueARM64_OpARM64SLL_0(v) case OpARM64SLLconst: @@ -303,6 +335,12 @@ func rewriteValueARM64(v *Value) bool { return rewriteValueARM64_OpARM64TSTWconst_0(v) case OpARM64TSTconst: return rewriteValueARM64_OpARM64TSTconst_0(v) + case OpARM64TSTshiftLL: + return rewriteValueARM64_OpARM64TSTshiftLL_0(v) + case OpARM64TSTshiftRA: + return rewriteValueARM64_OpARM64TSTshiftRA_0(v) + case OpARM64TSTshiftRL: + return rewriteValueARM64_OpARM64TSTshiftRL_0(v) case OpARM64UBFIZ: return rewriteValueARM64_OpARM64UBFIZ_0(v) case OpARM64UBFX: @@ -325,6 +363,8 @@ func rewriteValueARM64(v *Value) bool { return rewriteValueARM64_OpARM64XORshiftRA_0(v) case OpARM64XORshiftRL: return rewriteValueARM64_OpARM64XORshiftRL_0(v) + case OpAbs: + return rewriteValueARM64_OpAbs_0(v) case OpAdd16: return rewriteValueARM64_OpAdd16_0(v) case OpAdd32: @@ -731,12 +771,18 @@ func rewriteValueARM64(v *Value) bool { return rewriteValueARM64_OpPopCount32_0(v) case OpPopCount64: return rewriteValueARM64_OpPopCount64_0(v) + case OpRotateLeft32: + return rewriteValueARM64_OpRotateLeft32_0(v) + case OpRotateLeft64: + return rewriteValueARM64_OpRotateLeft64_0(v) case OpRound: return rewriteValueARM64_OpRound_0(v) case OpRound32F: return rewriteValueARM64_OpRound32F_0(v) case OpRound64F: return rewriteValueARM64_OpRound64F_0(v) + case OpRoundToEven: + return rewriteValueARM64_OpRoundToEven_0(v) case OpRsh16Ux16: return rewriteValueARM64_OpRsh16Ux16_0(v) case OpRsh16Ux32: @@ -910,7 +956,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return true } // match: (ADD a l:(MUL x y)) - // cond: l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: l.Uses==1 && clobber(l) // result: (MADD a x y) for { _ = v.Args[1] @@ -922,7 +968,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { _ = l.Args[1] x := l.Args[0] y := l.Args[1] - if !(l.Uses == 1 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MADD) @@ -932,7 +978,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return true } // match: (ADD l:(MUL x y) a) - // cond: l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: l.Uses==1 && clobber(l) // result: (MADD a x y) for { _ = v.Args[1] @@ -944,7 +990,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { x := l.Args[0] y := l.Args[1] a := v.Args[1] - if !(l.Uses == 1 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MADD) @@ -954,7 +1000,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return true } // match: (ADD a l:(MNEG x y)) - // cond: l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: l.Uses==1 && clobber(l) // result: (MSUB a x y) for { _ = v.Args[1] @@ -966,7 +1012,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { _ = l.Args[1] x := l.Args[0] y := l.Args[1] - if !(l.Uses == 1 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MSUB) @@ -976,7 +1022,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return true } // match: (ADD l:(MNEG x y) a) - // cond: l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: l.Uses==1 && clobber(l) // result: (MSUB a x y) for { _ = v.Args[1] @@ -988,7 +1034,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { x := l.Args[0] y := l.Args[1] a := v.Args[1] - if !(l.Uses == 1 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MSUB) @@ -998,7 +1044,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return true } // match: (ADD a l:(MULW x y)) - // cond: l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: a.Type.Size() != 8 && l.Uses==1 && clobber(l) // result: (MADDW a x y) for { _ = v.Args[1] @@ -1010,7 +1056,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { _ = l.Args[1] x := l.Args[0] y := l.Args[1] - if !(l.Uses == 1 && a.Type.Size() != 8 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(a.Type.Size() != 8 && l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MADDW) @@ -1020,7 +1066,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return true } // match: (ADD l:(MULW x y) a) - // cond: l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: a.Type.Size() != 8 && l.Uses==1 && clobber(l) // result: (MADDW a x y) for { _ = v.Args[1] @@ -1032,7 +1078,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { x := l.Args[0] y := l.Args[1] a := v.Args[1] - if !(l.Uses == 1 && a.Type.Size() != 8 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(a.Type.Size() != 8 && l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MADDW) @@ -1042,7 +1088,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return true } // match: (ADD a l:(MNEGW x y)) - // cond: l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: a.Type.Size() != 8 && l.Uses==1 && clobber(l) // result: (MSUBW a x y) for { _ = v.Args[1] @@ -1054,7 +1100,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { _ = l.Args[1] x := l.Args[0] y := l.Args[1] - if !(l.Uses == 1 && a.Type.Size() != 8 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(a.Type.Size() != 8 && l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MSUBW) @@ -1064,7 +1110,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return true } // match: (ADD l:(MNEGW x y) a) - // cond: l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: a.Type.Size() != 8 && l.Uses==1 && clobber(l) // result: (MSUBW a x y) for { _ = v.Args[1] @@ -1076,7 +1122,7 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { x := l.Args[0] y := l.Args[1] a := v.Args[1] - if !(l.Uses == 1 && a.Type.Size() != 8 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(a.Type.Size() != 8 && l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MSUBW) @@ -1088,6 +1134,10 @@ func rewriteValueARM64_OpARM64ADD_0(v *Value) bool { return false } func rewriteValueARM64_OpARM64ADD_10(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (ADD x (NEG y)) // cond: // result: (SUB x y) @@ -1246,6 +1296,925 @@ func rewriteValueARM64_OpARM64ADD_10(v *Value) bool { v.AddArg(y) return true } + // match: (ADD (SLL x (ANDconst <t> [63] y)) (CSEL0 <typ.UInt64> {cc} (SRL <typ.UInt64> x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SLL { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 63 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt64 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SRL { + break + } + if v_1_0.Type != typ.UInt64 { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 64 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 63 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 64 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 63 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (ADD (CSEL0 <typ.UInt64> {cc} (SRL <typ.UInt64> x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y)))) (SLL x (ANDconst <t> [63] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt64 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SRL { + break + } + if v_0_0.Type != typ.UInt64 { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 64 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 63 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 64 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 63 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SLL { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 63 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64ADD_20(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ + // match: (ADD (SRL <typ.UInt64> x (ANDconst <t> [63] y)) (CSEL0 <typ.UInt64> {cc} (SLL x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SRL { + break + } + if v_0.Type != typ.UInt64 { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 63 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt64 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SLL { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 64 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 63 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 64 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 63 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (ADD (CSEL0 <typ.UInt64> {cc} (SLL x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y)))) (SRL <typ.UInt64> x (ANDconst <t> [63] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt64 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SLL { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 64 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 63 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 64 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 63 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SRL { + break + } + if v_1.Type != typ.UInt64 { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 63 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (ADD (SLL x (ANDconst <t> [31] y)) (CSEL0 <typ.UInt32> {cc} (SRL <typ.UInt32> (MOVWUreg x) (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SLL { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 31 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt32 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SRL { + break + } + if v_1_0.Type != typ.UInt32 { + break + } + _ = v_1_0.Args[1] + v_1_0_0 := v_1_0.Args[0] + if v_1_0_0.Op != OpARM64MOVWUreg { + break + } + if x != v_1_0_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 32 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 31 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 32 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 31 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (ADD (CSEL0 <typ.UInt32> {cc} (SRL <typ.UInt32> (MOVWUreg x) (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y)))) (SLL x (ANDconst <t> [31] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt32 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SRL { + break + } + if v_0_0.Type != typ.UInt32 { + break + } + _ = v_0_0.Args[1] + v_0_0_0 := v_0_0.Args[0] + if v_0_0_0.Op != OpARM64MOVWUreg { + break + } + x := v_0_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 32 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 31 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 32 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 31 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SLL { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 31 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (ADD (SRL <typ.UInt32> (MOVWUreg x) (ANDconst <t> [31] y)) (CSEL0 <typ.UInt32> {cc} (SLL x (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SRL { + break + } + if v_0.Type != typ.UInt32 { + break + } + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64MOVWUreg { + break + } + x := v_0_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 31 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt32 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SLL { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 32 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 31 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 32 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 31 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (ADD (CSEL0 <typ.UInt32> {cc} (SLL x (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y)))) (SRL <typ.UInt32> (MOVWUreg x) (ANDconst <t> [31] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt32 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SLL { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 32 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 31 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 32 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 31 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SRL { + break + } + if v_1.Type != typ.UInt32 { + break + } + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64MOVWUreg { + break + } + if x != v_1_0.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 31 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v.AddArg(y) + return true + } return false } func rewriteValueARM64_OpARM64ADDconst_0(v *Value) bool { @@ -2395,6 +3364,132 @@ func rewriteValueARM64_OpARM64CMN_0(v *Value) bool { v.AddArg(x) return true } + // match: (CMN x0 x1:(SLLconst [c] y)) + // cond: clobberIfDead(x1) + // result: (CMNshiftLL x0 y [c]) + for { + _ = v.Args[1] + x0 := v.Args[0] + x1 := v.Args[1] + if x1.Op != OpARM64SLLconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64CMNshiftLL) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (CMN x1:(SLLconst [c] y) x0) + // cond: clobberIfDead(x1) + // result: (CMNshiftLL x0 y [c]) + for { + _ = v.Args[1] + x1 := v.Args[0] + if x1.Op != OpARM64SLLconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + x0 := v.Args[1] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64CMNshiftLL) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (CMN x0 x1:(SRLconst [c] y)) + // cond: clobberIfDead(x1) + // result: (CMNshiftRL x0 y [c]) + for { + _ = v.Args[1] + x0 := v.Args[0] + x1 := v.Args[1] + if x1.Op != OpARM64SRLconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64CMNshiftRL) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (CMN x1:(SRLconst [c] y) x0) + // cond: clobberIfDead(x1) + // result: (CMNshiftRL x0 y [c]) + for { + _ = v.Args[1] + x1 := v.Args[0] + if x1.Op != OpARM64SRLconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + x0 := v.Args[1] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64CMNshiftRL) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (CMN x0 x1:(SRAconst [c] y)) + // cond: clobberIfDead(x1) + // result: (CMNshiftRA x0 y [c]) + for { + _ = v.Args[1] + x0 := v.Args[0] + x1 := v.Args[1] + if x1.Op != OpARM64SRAconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64CMNshiftRA) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (CMN x1:(SRAconst [c] y) x0) + // cond: clobberIfDead(x1) + // result: (CMNshiftRA x0 y [c]) + for { + _ = v.Args[1] + x1 := v.Args[0] + if x1.Op != OpARM64SRAconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + x0 := v.Args[1] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64CMNshiftRA) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } return false } func rewriteValueARM64_OpARM64CMNW_0(v *Value) bool { @@ -2598,6 +3693,132 @@ func rewriteValueARM64_OpARM64CMNconst_0(v *Value) bool { } return false } +func rewriteValueARM64_OpARM64CMNshiftLL_0(v *Value) bool { + b := v.Block + _ = b + // match: (CMNshiftLL (MOVDconst [c]) x [d]) + // cond: + // result: (CMNconst [c] (SLLconst <x.Type> x [d])) + for { + d := v.AuxInt + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + v.reset(OpARM64CMNconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64SLLconst, x.Type) + v0.AuxInt = d + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (CMNshiftLL x (MOVDconst [c]) [d]) + // cond: + // result: (CMNconst x [int64(uint64(c)<<uint64(d))]) + for { + d := v.AuxInt + _ = v.Args[1] + x := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v.reset(OpARM64CMNconst) + v.AuxInt = int64(uint64(c) << uint64(d)) + v.AddArg(x) + return true + } + return false +} +func rewriteValueARM64_OpARM64CMNshiftRA_0(v *Value) bool { + b := v.Block + _ = b + // match: (CMNshiftRA (MOVDconst [c]) x [d]) + // cond: + // result: (CMNconst [c] (SRAconst <x.Type> x [d])) + for { + d := v.AuxInt + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + v.reset(OpARM64CMNconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64SRAconst, x.Type) + v0.AuxInt = d + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (CMNshiftRA x (MOVDconst [c]) [d]) + // cond: + // result: (CMNconst x [c>>uint64(d)]) + for { + d := v.AuxInt + _ = v.Args[1] + x := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v.reset(OpARM64CMNconst) + v.AuxInt = c >> uint64(d) + v.AddArg(x) + return true + } + return false +} +func rewriteValueARM64_OpARM64CMNshiftRL_0(v *Value) bool { + b := v.Block + _ = b + // match: (CMNshiftRL (MOVDconst [c]) x [d]) + // cond: + // result: (CMNconst [c] (SRLconst <x.Type> x [d])) + for { + d := v.AuxInt + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + v.reset(OpARM64CMNconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64SRLconst, x.Type) + v0.AuxInt = d + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (CMNshiftRL x (MOVDconst [c]) [d]) + // cond: + // result: (CMNconst x [int64(uint64(c)>>uint64(d))]) + for { + d := v.AuxInt + _ = v.Args[1] + x := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v.reset(OpARM64CMNconst) + v.AuxInt = int64(uint64(c) >> uint64(d)) + v.AddArg(x) + return true + } + return false +} func rewriteValueARM64_OpARM64CMP_0(v *Value) bool { b := v.Block _ = b @@ -3960,6 +5181,30 @@ func rewriteValueARM64_OpARM64FADDS_0(v *Value) bool { } return false } +func rewriteValueARM64_OpARM64FMOVDfpgp_0(v *Value) bool { + b := v.Block + _ = b + // match: (FMOVDfpgp <t> (Arg [off] {sym})) + // cond: + // result: @b.Func.Entry (Arg <t> [off] {sym}) + for { + t := v.Type + v_0 := v.Args[0] + if v_0.Op != OpArg { + break + } + off := v_0.AuxInt + sym := v_0.Aux + b = b.Func.Entry + v0 := b.NewValue0(v.Pos, OpArg, t) + v.reset(OpCopy) + v.AddArg(v0) + v0.AuxInt = off + v0.Aux = sym + return true + } + return false +} func rewriteValueARM64_OpARM64FMOVDgpfp_0(v *Value) bool { b := v.Block _ = b @@ -3989,6 +5234,33 @@ func rewriteValueARM64_OpARM64FMOVDload_0(v *Value) bool { _ = b config := b.Func.Config _ = config + // match: (FMOVDload [off] {sym} ptr (MOVDstore [off] {sym} ptr val _)) + // cond: + // result: (FMOVDgpfp val) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[1] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDstore { + break + } + if v_1.AuxInt != off { + break + } + if v_1.Aux != sym { + break + } + _ = v_1.Args[2] + if ptr != v_1.Args[0] { + break + } + val := v_1.Args[1] + v.reset(OpARM64FMOVDgpfp) + v.AddArg(val) + return true + } // match: (FMOVDload [off1] {sym} (ADDconst [off2] ptr) mem) // cond: is32Bit(off1+off2) && (ptr.Op != OpSB || !config.ctxt.Flag_shared) // result: (FMOVDload [off1+off2] {sym} ptr mem) @@ -4108,10 +5380,12 @@ func rewriteValueARM64_OpARM64FMOVDstore_0(v *Value) bool { _ = b config := b.Func.Config _ = config - // match: (FMOVDstore ptr (FMOVDgpfp val) mem) + // match: (FMOVDstore [off] {sym} ptr (FMOVDgpfp val) mem) // cond: - // result: (MOVDstore ptr val mem) + // result: (MOVDstore [off] {sym} ptr val mem) for { + off := v.AuxInt + sym := v.Aux _ = v.Args[2] ptr := v.Args[0] v_1 := v.Args[1] @@ -4121,6 +5395,8 @@ func rewriteValueARM64_OpARM64FMOVDstore_0(v *Value) bool { val := v_1.Args[0] mem := v.Args[2] v.reset(OpARM64MOVDstore) + v.AuxInt = off + v.Aux = sym v.AddArg(ptr) v.AddArg(val) v.AddArg(mem) @@ -4255,6 +5531,33 @@ func rewriteValueARM64_OpARM64FMOVSload_0(v *Value) bool { _ = b config := b.Func.Config _ = config + // match: (FMOVSload [off] {sym} ptr (MOVWstore [off] {sym} ptr val _)) + // cond: + // result: (FMOVSgpfp val) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[1] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVWstore { + break + } + if v_1.AuxInt != off { + break + } + if v_1.Aux != sym { + break + } + _ = v_1.Args[2] + if ptr != v_1.Args[0] { + break + } + val := v_1.Args[1] + v.reset(OpARM64FMOVSgpfp) + v.AddArg(val) + return true + } // match: (FMOVSload [off1] {sym} (ADDconst [off2] ptr) mem) // cond: is32Bit(off1+off2) && (ptr.Op != OpSB || !config.ctxt.Flag_shared) // result: (FMOVSload [off1+off2] {sym} ptr mem) @@ -4374,6 +5677,28 @@ func rewriteValueARM64_OpARM64FMOVSstore_0(v *Value) bool { _ = b config := b.Func.Config _ = config + // match: (FMOVSstore [off] {sym} ptr (FMOVSgpfp val) mem) + // cond: + // result: (MOVWstore [off] {sym} ptr val mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64FMOVSgpfp { + break + } + val := v_1.Args[0] + mem := v.Args[2] + v.reset(OpARM64MOVWstore) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (FMOVSstore [off1] {sym} (ADDconst [off2] ptr) val mem) // cond: is32Bit(off1+off2) && (ptr.Op != OpSB || !config.ctxt.Flag_shared) // result: (FMOVSstore [off1+off2] {sym} ptr val mem) @@ -5474,6 +6799,1024 @@ func rewriteValueARM64_OpARM64LessThanU_0(v *Value) bool { } return false } +func rewriteValueARM64_OpARM64MADD_0(v *Value) bool { + b := v.Block + _ = b + // match: (MADD a x (MOVDconst [-1])) + // cond: + // result: (SUB a x) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + if v_2.AuxInt != -1 { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADD a _ (MOVDconst [0])) + // cond: + // result: a + for { + _ = v.Args[2] + a := v.Args[0] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + if v_2.AuxInt != 0 { + break + } + v.reset(OpCopy) + v.Type = a.Type + v.AddArg(a) + return true + } + // match: (MADD a x (MOVDconst [1])) + // cond: + // result: (ADD a x) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + if v_2.AuxInt != 1 { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADD a x (MOVDconst [c])) + // cond: isPowerOfTwo(c) + // result: (ADDshiftLL a x [log2(c)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADD a x (MOVDconst [c])) + // cond: isPowerOfTwo(c-1) && c>=3 + // result: (ADD a (ADDshiftLL <x.Type> x x [log2(c-1)])) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c-1) && c >= 3) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = log2(c - 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a x (MOVDconst [c])) + // cond: isPowerOfTwo(c+1) && c>=7 + // result: (SUB a (SUBshiftLL <x.Type> x x [log2(c+1)])) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c+1) && c >= 7) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = log2(c + 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a x (MOVDconst [c])) + // cond: c%3 == 0 && isPowerOfTwo(c/3) + // result: (SUBshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%3 == 0 && isPowerOfTwo(c/3)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 3) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a x (MOVDconst [c])) + // cond: c%5 == 0 && isPowerOfTwo(c/5) + // result: (ADDshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%5 == 0 && isPowerOfTwo(c/5)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 5) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a x (MOVDconst [c])) + // cond: c%7 == 0 && isPowerOfTwo(c/7) + // result: (SUBshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%7 == 0 && isPowerOfTwo(c/7)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 7) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a x (MOVDconst [c])) + // cond: c%9 == 0 && isPowerOfTwo(c/9) + // result: (ADDshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%9 == 0 && isPowerOfTwo(c/9)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 9) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64MADD_10(v *Value) bool { + b := v.Block + _ = b + // match: (MADD a (MOVDconst [-1]) x) + // cond: + // result: (SUB a x) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + if v_1.AuxInt != -1 { + break + } + x := v.Args[2] + v.reset(OpARM64SUB) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADD a (MOVDconst [0]) _) + // cond: + // result: a + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + if v_1.AuxInt != 0 { + break + } + v.reset(OpCopy) + v.Type = a.Type + v.AddArg(a) + return true + } + // match: (MADD a (MOVDconst [1]) x) + // cond: + // result: (ADD a x) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + if v_1.AuxInt != 1 { + break + } + x := v.Args[2] + v.reset(OpARM64ADD) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADD a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c) + // result: (ADDshiftLL a x [log2(c)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADD a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c-1) && c>=3 + // result: (ADD a (ADDshiftLL <x.Type> x x [log2(c-1)])) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c-1) && c >= 3) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = log2(c - 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c+1) && c>=7 + // result: (SUB a (SUBshiftLL <x.Type> x x [log2(c+1)])) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c+1) && c >= 7) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = log2(c + 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a (MOVDconst [c]) x) + // cond: c%3 == 0 && isPowerOfTwo(c/3) + // result: (SUBshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%3 == 0 && isPowerOfTwo(c/3)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 3) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a (MOVDconst [c]) x) + // cond: c%5 == 0 && isPowerOfTwo(c/5) + // result: (ADDshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%5 == 0 && isPowerOfTwo(c/5)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 5) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a (MOVDconst [c]) x) + // cond: c%7 == 0 && isPowerOfTwo(c/7) + // result: (SUBshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%7 == 0 && isPowerOfTwo(c/7)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 7) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADD a (MOVDconst [c]) x) + // cond: c%9 == 0 && isPowerOfTwo(c/9) + // result: (ADDshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%9 == 0 && isPowerOfTwo(c/9)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 9) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64MADD_20(v *Value) bool { + b := v.Block + _ = b + // match: (MADD (MOVDconst [c]) x y) + // cond: + // result: (ADDconst [c] (MUL <x.Type> x y)) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + y := v.Args[2] + v.reset(OpARM64ADDconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64MUL, x.Type) + v0.AddArg(x) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (MADD a (MOVDconst [c]) (MOVDconst [d])) + // cond: + // result: (ADDconst [c*d] a) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + d := v_2.AuxInt + v.reset(OpARM64ADDconst) + v.AuxInt = c * d + v.AddArg(a) + return true + } + return false +} +func rewriteValueARM64_OpARM64MADDW_0(v *Value) bool { + b := v.Block + _ = b + // match: (MADDW a x (MOVDconst [c])) + // cond: int32(c)==-1 + // result: (SUB a x) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(int32(c) == -1) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADDW a _ (MOVDconst [c])) + // cond: int32(c)==0 + // result: a + for { + _ = v.Args[2] + a := v.Args[0] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(int32(c) == 0) { + break + } + v.reset(OpCopy) + v.Type = a.Type + v.AddArg(a) + return true + } + // match: (MADDW a x (MOVDconst [c])) + // cond: int32(c)==1 + // result: (ADD a x) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(int32(c) == 1) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADDW a x (MOVDconst [c])) + // cond: isPowerOfTwo(c) + // result: (ADDshiftLL a x [log2(c)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADDW a x (MOVDconst [c])) + // cond: isPowerOfTwo(c-1) && int32(c)>=3 + // result: (ADD a (ADDshiftLL <x.Type> x x [log2(c-1)])) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c-1) && int32(c) >= 3) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = log2(c - 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a x (MOVDconst [c])) + // cond: isPowerOfTwo(c+1) && int32(c)>=7 + // result: (SUB a (SUBshiftLL <x.Type> x x [log2(c+1)])) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c+1) && int32(c) >= 7) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = log2(c + 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a x (MOVDconst [c])) + // cond: c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c) + // result: (SUBshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 3) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a x (MOVDconst [c])) + // cond: c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c) + // result: (ADDshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 5) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a x (MOVDconst [c])) + // cond: c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) + // result: (SUBshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 7) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a x (MOVDconst [c])) + // cond: c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) + // result: (ADDshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 9) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64MADDW_10(v *Value) bool { + b := v.Block + _ = b + // match: (MADDW a (MOVDconst [c]) x) + // cond: int32(c)==-1 + // result: (SUB a x) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(int32(c) == -1) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADDW a (MOVDconst [c]) _) + // cond: int32(c)==0 + // result: a + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + if !(int32(c) == 0) { + break + } + v.reset(OpCopy) + v.Type = a.Type + v.AddArg(a) + return true + } + // match: (MADDW a (MOVDconst [c]) x) + // cond: int32(c)==1 + // result: (ADD a x) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(int32(c) == 1) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADDW a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c) + // result: (ADDshiftLL a x [log2(c)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MADDW a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c-1) && int32(c)>=3 + // result: (ADD a (ADDshiftLL <x.Type> x x [log2(c-1)])) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c-1) && int32(c) >= 3) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = log2(c - 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c+1) && int32(c)>=7 + // result: (SUB a (SUBshiftLL <x.Type> x x [log2(c+1)])) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c+1) && int32(c) >= 7) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = log2(c + 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a (MOVDconst [c]) x) + // cond: c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c) + // result: (SUBshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 3) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a (MOVDconst [c]) x) + // cond: c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c) + // result: (ADDshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 5) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a (MOVDconst [c]) x) + // cond: c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) + // result: (SUBshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 7) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MADDW a (MOVDconst [c]) x) + // cond: c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) + // result: (ADDshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 9) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64MADDW_20(v *Value) bool { + b := v.Block + _ = b + // match: (MADDW (MOVDconst [c]) x y) + // cond: + // result: (ADDconst [c] (MULW <x.Type> x y)) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + y := v.Args[2] + v.reset(OpARM64ADDconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64MULW, x.Type) + v0.AddArg(x) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (MADDW a (MOVDconst [c]) (MOVDconst [d])) + // cond: + // result: (ADDconst [int64(int32(c)*int32(d))] a) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + d := v_2.AuxInt + v.reset(OpARM64ADDconst) + v.AuxInt = int64(int32(c) * int32(d)) + v.AddArg(a) + return true + } + return false +} func rewriteValueARM64_OpARM64MNEG_0(v *Value) bool { b := v.Block _ = b @@ -10145,6 +12488,33 @@ func rewriteValueARM64_OpARM64MOVDload_0(v *Value) bool { _ = b config := b.Func.Config _ = config + // match: (MOVDload [off] {sym} ptr (FMOVDstore [off] {sym} ptr val _)) + // cond: + // result: (FMOVDfpgp val) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[1] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64FMOVDstore { + break + } + if v_1.AuxInt != off { + break + } + if v_1.Aux != sym { + break + } + _ = v_1.Args[2] + if ptr != v_1.Args[0] { + break + } + val := v_1.Args[1] + v.reset(OpARM64FMOVDfpgp) + v.AddArg(val) + return true + } // match: (MOVDload [off1] {sym} (ADDconst [off2] ptr) mem) // cond: is32Bit(off1+off2) && (ptr.Op != OpSB || !config.ctxt.Flag_shared) // result: (MOVDload [off1+off2] {sym} ptr mem) @@ -10447,10 +12817,12 @@ func rewriteValueARM64_OpARM64MOVDstore_0(v *Value) bool { _ = b config := b.Func.Config _ = config - // match: (MOVDstore ptr (FMOVDfpgp val) mem) + // match: (MOVDstore [off] {sym} ptr (FMOVDfpgp val) mem) // cond: - // result: (FMOVDstore ptr val mem) + // result: (FMOVDstore [off] {sym} ptr val mem) for { + off := v.AuxInt + sym := v.Aux _ = v.Args[2] ptr := v.Args[0] v_1 := v.Args[1] @@ -10460,6 +12832,8 @@ func rewriteValueARM64_OpARM64MOVDstore_0(v *Value) bool { val := v_1.Args[0] mem := v.Args[2] v.reset(OpARM64FMOVDstore) + v.AuxInt = off + v.Aux = sym v.AddArg(ptr) v.AddArg(val) v.AddArg(mem) @@ -13659,6 +16033,33 @@ func rewriteValueARM64_OpARM64MOVWUload_0(v *Value) bool { _ = b config := b.Func.Config _ = config + // match: (MOVWUload [off] {sym} ptr (FMOVSstore [off] {sym} ptr val _)) + // cond: + // result: (FMOVSfpgp val) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[1] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64FMOVSstore { + break + } + if v_1.AuxInt != off { + break + } + if v_1.Aux != sym { + break + } + _ = v_1.Args[2] + if ptr != v_1.Args[0] { + break + } + val := v_1.Args[1] + v.reset(OpARM64FMOVSfpgp) + v.AddArg(val) + return true + } // match: (MOVWUload [off1] {sym} (ADDconst [off2] ptr) mem) // cond: is32Bit(off1+off2) && (ptr.Op != OpSB || !config.ctxt.Flag_shared) // result: (MOVWUload [off1+off2] {sym} ptr mem) @@ -14683,6 +17084,28 @@ func rewriteValueARM64_OpARM64MOVWstore_0(v *Value) bool { _ = b config := b.Func.Config _ = config + // match: (MOVWstore [off] {sym} ptr (FMOVSfpgp val) mem) + // cond: + // result: (FMOVSstore [off] {sym} ptr val mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64FMOVSfpgp { + break + } + val := v_1.Args[0] + mem := v.Args[2] + v.reset(OpARM64FMOVSstore) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (MOVWstore [off1] {sym} (ADDconst [off2] ptr) val mem) // cond: is32Bit(off1+off2) && (ptr.Op != OpSB || !config.ctxt.Flag_shared) // result: (MOVWstore [off1+off2] {sym} ptr val mem) @@ -14946,6 +17369,11 @@ func rewriteValueARM64_OpARM64MOVWstore_0(v *Value) bool { v.AddArg(mem) return true } + return false +} +func rewriteValueARM64_OpARM64MOVWstore_10(v *Value) bool { + b := v.Block + _ = b // match: (MOVWstore [4] {s} (ADDshiftLL [2] ptr0 idx0) (SRLconst [32] w) x:(MOVWstoreidx4 ptr1 idx1 w mem)) // cond: x.Uses == 1 && s == nil && isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) && clobber(x) // result: (MOVDstoreidx ptr1 (SLLconst <idx1.Type> [2] idx1) w mem) @@ -14997,11 +17425,6 @@ func rewriteValueARM64_OpARM64MOVWstore_0(v *Value) bool { v.AddArg(mem) return true } - return false -} -func rewriteValueARM64_OpARM64MOVWstore_10(v *Value) bool { - b := v.Block - _ = b // match: (MOVWstore [i] {s} ptr0 (SRLconst [j] w) x:(MOVWstore [i-4] {s} ptr1 w0:(SRLconst [j-32] w) mem)) // cond: x.Uses == 1 && isSamePtr(ptr0, ptr1) && clobber(x) // result: (MOVDstore [i-4] {s} ptr0 w0 mem) @@ -15784,6 +18207,1024 @@ func rewriteValueARM64_OpARM64MOVWstorezeroidx4_0(v *Value) bool { } return false } +func rewriteValueARM64_OpARM64MSUB_0(v *Value) bool { + b := v.Block + _ = b + // match: (MSUB a x (MOVDconst [-1])) + // cond: + // result: (ADD a x) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + if v_2.AuxInt != -1 { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUB a _ (MOVDconst [0])) + // cond: + // result: a + for { + _ = v.Args[2] + a := v.Args[0] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + if v_2.AuxInt != 0 { + break + } + v.reset(OpCopy) + v.Type = a.Type + v.AddArg(a) + return true + } + // match: (MSUB a x (MOVDconst [1])) + // cond: + // result: (SUB a x) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + if v_2.AuxInt != 1 { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUB a x (MOVDconst [c])) + // cond: isPowerOfTwo(c) + // result: (SUBshiftLL a x [log2(c)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUB a x (MOVDconst [c])) + // cond: isPowerOfTwo(c-1) && c>=3 + // result: (SUB a (ADDshiftLL <x.Type> x x [log2(c-1)])) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c-1) && c >= 3) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = log2(c - 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a x (MOVDconst [c])) + // cond: isPowerOfTwo(c+1) && c>=7 + // result: (ADD a (SUBshiftLL <x.Type> x x [log2(c+1)])) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c+1) && c >= 7) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = log2(c + 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a x (MOVDconst [c])) + // cond: c%3 == 0 && isPowerOfTwo(c/3) + // result: (ADDshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%3 == 0 && isPowerOfTwo(c/3)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 3) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a x (MOVDconst [c])) + // cond: c%5 == 0 && isPowerOfTwo(c/5) + // result: (SUBshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%5 == 0 && isPowerOfTwo(c/5)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 5) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a x (MOVDconst [c])) + // cond: c%7 == 0 && isPowerOfTwo(c/7) + // result: (ADDshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%7 == 0 && isPowerOfTwo(c/7)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 7) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a x (MOVDconst [c])) + // cond: c%9 == 0 && isPowerOfTwo(c/9) + // result: (SUBshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%9 == 0 && isPowerOfTwo(c/9)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 9) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64MSUB_10(v *Value) bool { + b := v.Block + _ = b + // match: (MSUB a (MOVDconst [-1]) x) + // cond: + // result: (ADD a x) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + if v_1.AuxInt != -1 { + break + } + x := v.Args[2] + v.reset(OpARM64ADD) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUB a (MOVDconst [0]) _) + // cond: + // result: a + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + if v_1.AuxInt != 0 { + break + } + v.reset(OpCopy) + v.Type = a.Type + v.AddArg(a) + return true + } + // match: (MSUB a (MOVDconst [1]) x) + // cond: + // result: (SUB a x) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + if v_1.AuxInt != 1 { + break + } + x := v.Args[2] + v.reset(OpARM64SUB) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUB a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c) + // result: (SUBshiftLL a x [log2(c)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUB a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c-1) && c>=3 + // result: (SUB a (ADDshiftLL <x.Type> x x [log2(c-1)])) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c-1) && c >= 3) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = log2(c - 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c+1) && c>=7 + // result: (ADD a (SUBshiftLL <x.Type> x x [log2(c+1)])) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c+1) && c >= 7) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = log2(c + 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a (MOVDconst [c]) x) + // cond: c%3 == 0 && isPowerOfTwo(c/3) + // result: (ADDshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%3 == 0 && isPowerOfTwo(c/3)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 3) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a (MOVDconst [c]) x) + // cond: c%5 == 0 && isPowerOfTwo(c/5) + // result: (SUBshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%5 == 0 && isPowerOfTwo(c/5)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 5) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a (MOVDconst [c]) x) + // cond: c%7 == 0 && isPowerOfTwo(c/7) + // result: (ADDshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%7 == 0 && isPowerOfTwo(c/7)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 7) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUB a (MOVDconst [c]) x) + // cond: c%9 == 0 && isPowerOfTwo(c/9) + // result: (SUBshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%9 == 0 && isPowerOfTwo(c/9)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 9) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64MSUB_20(v *Value) bool { + b := v.Block + _ = b + // match: (MSUB (MOVDconst [c]) x y) + // cond: + // result: (ADDconst [c] (MNEG <x.Type> x y)) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + y := v.Args[2] + v.reset(OpARM64ADDconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64MNEG, x.Type) + v0.AddArg(x) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (MSUB a (MOVDconst [c]) (MOVDconst [d])) + // cond: + // result: (SUBconst [c*d] a) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + d := v_2.AuxInt + v.reset(OpARM64SUBconst) + v.AuxInt = c * d + v.AddArg(a) + return true + } + return false +} +func rewriteValueARM64_OpARM64MSUBW_0(v *Value) bool { + b := v.Block + _ = b + // match: (MSUBW a x (MOVDconst [c])) + // cond: int32(c)==-1 + // result: (ADD a x) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(int32(c) == -1) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUBW a _ (MOVDconst [c])) + // cond: int32(c)==0 + // result: a + for { + _ = v.Args[2] + a := v.Args[0] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(int32(c) == 0) { + break + } + v.reset(OpCopy) + v.Type = a.Type + v.AddArg(a) + return true + } + // match: (MSUBW a x (MOVDconst [c])) + // cond: int32(c)==1 + // result: (SUB a x) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(int32(c) == 1) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUBW a x (MOVDconst [c])) + // cond: isPowerOfTwo(c) + // result: (SUBshiftLL a x [log2(c)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUBW a x (MOVDconst [c])) + // cond: isPowerOfTwo(c-1) && int32(c)>=3 + // result: (SUB a (ADDshiftLL <x.Type> x x [log2(c-1)])) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c-1) && int32(c) >= 3) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = log2(c - 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a x (MOVDconst [c])) + // cond: isPowerOfTwo(c+1) && int32(c)>=7 + // result: (ADD a (SUBshiftLL <x.Type> x x [log2(c+1)])) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(isPowerOfTwo(c+1) && int32(c) >= 7) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = log2(c + 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a x (MOVDconst [c])) + // cond: c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c) + // result: (ADDshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 3) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a x (MOVDconst [c])) + // cond: c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c) + // result: (SUBshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 5) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a x (MOVDconst [c])) + // cond: c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) + // result: (ADDshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 7) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a x (MOVDconst [c])) + // cond: c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) + // result: (SUBshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + for { + _ = v.Args[2] + a := v.Args[0] + x := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + c := v_2.AuxInt + if !(c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 9) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64MSUBW_10(v *Value) bool { + b := v.Block + _ = b + // match: (MSUBW a (MOVDconst [c]) x) + // cond: int32(c)==-1 + // result: (ADD a x) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(int32(c) == -1) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUBW a (MOVDconst [c]) _) + // cond: int32(c)==0 + // result: a + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + if !(int32(c) == 0) { + break + } + v.reset(OpCopy) + v.Type = a.Type + v.AddArg(a) + return true + } + // match: (MSUBW a (MOVDconst [c]) x) + // cond: int32(c)==1 + // result: (SUB a x) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(int32(c) == 1) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUBW a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c) + // result: (SUBshiftLL a x [log2(c)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c) + v.AddArg(a) + v.AddArg(x) + return true + } + // match: (MSUBW a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c-1) && int32(c)>=3 + // result: (SUB a (ADDshiftLL <x.Type> x x [log2(c-1)])) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c-1) && int32(c) >= 3) { + break + } + v.reset(OpARM64SUB) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = log2(c - 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a (MOVDconst [c]) x) + // cond: isPowerOfTwo(c+1) && int32(c)>=7 + // result: (ADD a (SUBshiftLL <x.Type> x x [log2(c+1)])) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(isPowerOfTwo(c+1) && int32(c) >= 7) { + break + } + v.reset(OpARM64ADD) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = log2(c + 1) + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a (MOVDconst [c]) x) + // cond: c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c) + // result: (ADDshiftLL a (SUBshiftLL <x.Type> x x [2]) [log2(c/3)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%3 == 0 && isPowerOfTwo(c/3) && is32Bit(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 3) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a (MOVDconst [c]) x) + // cond: c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c) + // result: (SUBshiftLL a (ADDshiftLL <x.Type> x x [2]) [log2(c/5)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%5 == 0 && isPowerOfTwo(c/5) && is32Bit(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 5) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 2 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a (MOVDconst [c]) x) + // cond: c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c) + // result: (ADDshiftLL a (SUBshiftLL <x.Type> x x [3]) [log2(c/7)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%7 == 0 && isPowerOfTwo(c/7) && is32Bit(c)) { + break + } + v.reset(OpARM64ADDshiftLL) + v.AuxInt = log2(c / 7) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64SUBshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MSUBW a (MOVDconst [c]) x) + // cond: c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c) + // result: (SUBshiftLL a (ADDshiftLL <x.Type> x x [3]) [log2(c/9)]) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + x := v.Args[2] + if !(c%9 == 0 && isPowerOfTwo(c/9) && is32Bit(c)) { + break + } + v.reset(OpARM64SUBshiftLL) + v.AuxInt = log2(c / 9) + v.AddArg(a) + v0 := b.NewValue0(v.Pos, OpARM64ADDshiftLL, x.Type) + v0.AuxInt = 3 + v0.AddArg(x) + v0.AddArg(x) + v.AddArg(v0) + return true + } + return false +} +func rewriteValueARM64_OpARM64MSUBW_20(v *Value) bool { + b := v.Block + _ = b + // match: (MSUBW (MOVDconst [c]) x y) + // cond: + // result: (ADDconst [c] (MNEGW <x.Type> x y)) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + y := v.Args[2] + v.reset(OpARM64ADDconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64MNEGW, x.Type) + v0.AddArg(x) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (MSUBW a (MOVDconst [c]) (MOVDconst [d])) + // cond: + // result: (SUBconst [int64(int32(c)*int32(d))] a) + for { + _ = v.Args[2] + a := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v_2 := v.Args[2] + if v_2.Op != OpARM64MOVDconst { + break + } + d := v_2.AuxInt + v.reset(OpARM64SUBconst) + v.AuxInt = int64(int32(c) * int32(d)) + v.AddArg(a) + return true + } + return false +} func rewriteValueARM64_OpARM64MUL_0(v *Value) bool { // match: (MUL (NEG x) y) // cond: @@ -16794,6 +20235,111 @@ func rewriteValueARM64_OpARM64MVN_0(v *Value) bool { v.AuxInt = ^c return true } + // match: (MVN x:(SLLconst [c] y)) + // cond: clobberIfDead(x) + // result: (MVNshiftLL [c] y) + for { + x := v.Args[0] + if x.Op != OpARM64SLLconst { + break + } + c := x.AuxInt + y := x.Args[0] + if !(clobberIfDead(x)) { + break + } + v.reset(OpARM64MVNshiftLL) + v.AuxInt = c + v.AddArg(y) + return true + } + // match: (MVN x:(SRLconst [c] y)) + // cond: clobberIfDead(x) + // result: (MVNshiftRL [c] y) + for { + x := v.Args[0] + if x.Op != OpARM64SRLconst { + break + } + c := x.AuxInt + y := x.Args[0] + if !(clobberIfDead(x)) { + break + } + v.reset(OpARM64MVNshiftRL) + v.AuxInt = c + v.AddArg(y) + return true + } + // match: (MVN x:(SRAconst [c] y)) + // cond: clobberIfDead(x) + // result: (MVNshiftRA [c] y) + for { + x := v.Args[0] + if x.Op != OpARM64SRAconst { + break + } + c := x.AuxInt + y := x.Args[0] + if !(clobberIfDead(x)) { + break + } + v.reset(OpARM64MVNshiftRA) + v.AuxInt = c + v.AddArg(y) + return true + } + return false +} +func rewriteValueARM64_OpARM64MVNshiftLL_0(v *Value) bool { + // match: (MVNshiftLL (MOVDconst [c]) [d]) + // cond: + // result: (MOVDconst [^int64(uint64(c)<<uint64(d))]) + for { + d := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + v.reset(OpARM64MOVDconst) + v.AuxInt = ^int64(uint64(c) << uint64(d)) + return true + } + return false +} +func rewriteValueARM64_OpARM64MVNshiftRA_0(v *Value) bool { + // match: (MVNshiftRA (MOVDconst [c]) [d]) + // cond: + // result: (MOVDconst [^(c>>uint64(d))]) + for { + d := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + v.reset(OpARM64MOVDconst) + v.AuxInt = ^(c >> uint64(d)) + return true + } + return false +} +func rewriteValueARM64_OpARM64MVNshiftRL_0(v *Value) bool { + // match: (MVNshiftRL (MOVDconst [c]) [d]) + // cond: + // result: (MOVDconst [^int64(uint64(c)>>uint64(d))]) + for { + d := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + v.reset(OpARM64MOVDconst) + v.AuxInt = ^int64(uint64(c) >> uint64(d)) + return true + } return false } func rewriteValueARM64_OpARM64NEG_0(v *Value) bool { @@ -16842,6 +20388,111 @@ func rewriteValueARM64_OpARM64NEG_0(v *Value) bool { v.AuxInt = -c return true } + // match: (NEG x:(SLLconst [c] y)) + // cond: clobberIfDead(x) + // result: (NEGshiftLL [c] y) + for { + x := v.Args[0] + if x.Op != OpARM64SLLconst { + break + } + c := x.AuxInt + y := x.Args[0] + if !(clobberIfDead(x)) { + break + } + v.reset(OpARM64NEGshiftLL) + v.AuxInt = c + v.AddArg(y) + return true + } + // match: (NEG x:(SRLconst [c] y)) + // cond: clobberIfDead(x) + // result: (NEGshiftRL [c] y) + for { + x := v.Args[0] + if x.Op != OpARM64SRLconst { + break + } + c := x.AuxInt + y := x.Args[0] + if !(clobberIfDead(x)) { + break + } + v.reset(OpARM64NEGshiftRL) + v.AuxInt = c + v.AddArg(y) + return true + } + // match: (NEG x:(SRAconst [c] y)) + // cond: clobberIfDead(x) + // result: (NEGshiftRA [c] y) + for { + x := v.Args[0] + if x.Op != OpARM64SRAconst { + break + } + c := x.AuxInt + y := x.Args[0] + if !(clobberIfDead(x)) { + break + } + v.reset(OpARM64NEGshiftRA) + v.AuxInt = c + v.AddArg(y) + return true + } + return false +} +func rewriteValueARM64_OpARM64NEGshiftLL_0(v *Value) bool { + // match: (NEGshiftLL (MOVDconst [c]) [d]) + // cond: + // result: (MOVDconst [-int64(uint64(c)<<uint64(d))]) + for { + d := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + v.reset(OpARM64MOVDconst) + v.AuxInt = -int64(uint64(c) << uint64(d)) + return true + } + return false +} +func rewriteValueARM64_OpARM64NEGshiftRA_0(v *Value) bool { + // match: (NEGshiftRA (MOVDconst [c]) [d]) + // cond: + // result: (MOVDconst [-(c>>uint64(d))]) + for { + d := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + v.reset(OpARM64MOVDconst) + v.AuxInt = -(c >> uint64(d)) + return true + } + return false +} +func rewriteValueARM64_OpARM64NEGshiftRL_0(v *Value) bool { + // match: (NEGshiftRL (MOVDconst [c]) [d]) + // cond: + // result: (MOVDconst [-int64(uint64(c)>>uint64(d))]) + for { + d := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + v.reset(OpARM64MOVDconst) + v.AuxInt = -int64(uint64(c) >> uint64(d)) + return true + } return false } func rewriteValueARM64_OpARM64NotEqual_0(v *Value) bool { @@ -17109,6 +20760,8 @@ func rewriteValueARM64_OpARM64OR_0(v *Value) bool { func rewriteValueARM64_OpARM64OR_10(v *Value) bool { b := v.Block _ = b + typ := &b.Func.Config.Types + _ = typ // match: (OR x1:(SRAconst [c] y) x0) // cond: clobberIfDead(x1) // result: (ORshiftRA x0 y [c]) @@ -17130,6 +20783,918 @@ func rewriteValueARM64_OpARM64OR_10(v *Value) bool { v.AddArg(y) return true } + // match: (OR (SLL x (ANDconst <t> [63] y)) (CSEL0 <typ.UInt64> {cc} (SRL <typ.UInt64> x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SLL { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 63 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt64 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SRL { + break + } + if v_1_0.Type != typ.UInt64 { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 64 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 63 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 64 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 63 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (OR (CSEL0 <typ.UInt64> {cc} (SRL <typ.UInt64> x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y)))) (SLL x (ANDconst <t> [63] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt64 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SRL { + break + } + if v_0_0.Type != typ.UInt64 { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 64 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 63 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 64 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 63 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SLL { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 63 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (OR (SRL <typ.UInt64> x (ANDconst <t> [63] y)) (CSEL0 <typ.UInt64> {cc} (SLL x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SRL { + break + } + if v_0.Type != typ.UInt64 { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 63 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt64 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SLL { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 64 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 63 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 64 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 63 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (OR (CSEL0 <typ.UInt64> {cc} (SLL x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y)))) (SRL <typ.UInt64> x (ANDconst <t> [63] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt64 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SLL { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 64 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 63 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 64 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 63 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SRL { + break + } + if v_1.Type != typ.UInt64 { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 63 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (OR (SLL x (ANDconst <t> [31] y)) (CSEL0 <typ.UInt32> {cc} (SRL <typ.UInt32> (MOVWUreg x) (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SLL { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 31 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt32 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SRL { + break + } + if v_1_0.Type != typ.UInt32 { + break + } + _ = v_1_0.Args[1] + v_1_0_0 := v_1_0.Args[0] + if v_1_0_0.Op != OpARM64MOVWUreg { + break + } + if x != v_1_0_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 32 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 31 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 32 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 31 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (OR (CSEL0 <typ.UInt32> {cc} (SRL <typ.UInt32> (MOVWUreg x) (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y)))) (SLL x (ANDconst <t> [31] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt32 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SRL { + break + } + if v_0_0.Type != typ.UInt32 { + break + } + _ = v_0_0.Args[1] + v_0_0_0 := v_0_0.Args[0] + if v_0_0_0.Op != OpARM64MOVWUreg { + break + } + x := v_0_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 32 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 31 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 32 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 31 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SLL { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 31 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (OR (SRL <typ.UInt32> (MOVWUreg x) (ANDconst <t> [31] y)) (CSEL0 <typ.UInt32> {cc} (SLL x (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SRL { + break + } + if v_0.Type != typ.UInt32 { + break + } + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64MOVWUreg { + break + } + x := v_0_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 31 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt32 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SLL { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 32 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 31 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 32 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 31 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (OR (CSEL0 <typ.UInt32> {cc} (SLL x (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y)))) (SRL <typ.UInt32> (MOVWUreg x) (ANDconst <t> [31] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt32 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SLL { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 32 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 31 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 32 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 31 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SRL { + break + } + if v_1.Type != typ.UInt32 { + break + } + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64MOVWUreg { + break + } + if x != v_1_0.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 31 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v.AddArg(y) + return true + } // match: (OR (UBFIZ [bfc] x) (ANDconst [ac] y)) // cond: ac == ^((1<<uint(getARM64BFwidth(bfc))-1) << uint(getARM64BFlsb(bfc))) // result: (BFI [bfc] y x) @@ -17156,6 +21721,11 @@ func rewriteValueARM64_OpARM64OR_10(v *Value) bool { v.AddArg(x) return true } + return false +} +func rewriteValueARM64_OpARM64OR_20(v *Value) bool { + b := v.Block + _ = b // match: (OR (ANDconst [ac] y) (UBFIZ [bfc] x)) // cond: ac == ^((1<<uint(getARM64BFwidth(bfc))-1) << uint(getARM64BFlsb(bfc))) // result: (BFI [bfc] y x) @@ -17822,11 +22392,6 @@ func rewriteValueARM64_OpARM64OR_10(v *Value) bool { v0.AddArg(mem) return true } - return false -} -func rewriteValueARM64_OpARM64OR_20(v *Value) bool { - b := v.Block - _ = b // match: (OR <t> y3:(MOVDnop x3:(MOVBUloadidx ptr idx mem)) o0:(ORshiftLL [8] o1:(ORshiftLL [16] s0:(SLLconst [24] y0:(MOVDnop x0:(MOVBUloadidx ptr (ADDconst [3] idx) mem))) y1:(MOVDnop x1:(MOVBUloadidx ptr (ADDconst [2] idx) mem))) y2:(MOVDnop x2:(MOVBUloadidx ptr (ADDconst [1] idx) mem)))) // cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && y0.Uses == 1 && y1.Uses == 1 && y2.Uses == 1 && y3.Uses == 1 && o0.Uses == 1 && o1.Uses == 1 && s0.Uses == 1 && mergePoint(b,x0,x1,x2,x3) != nil && clobber(x0) && clobber(x1) && clobber(x2) && clobber(x3) && clobber(y0) && clobber(y1) && clobber(y2) && clobber(y3) && clobber(o0) && clobber(o1) && clobber(s0) // result: @mergePoint(b,x0,x1,x2,x3) (MOVWUloadidx <t> ptr idx mem) @@ -18177,6 +22742,11 @@ func rewriteValueARM64_OpARM64OR_20(v *Value) bool { v0.AddArg(mem) return true } + return false +} +func rewriteValueARM64_OpARM64OR_30(v *Value) bool { + b := v.Block + _ = b // match: (OR <t> y7:(MOVDnop x7:(MOVBUload [i0] {s} p mem)) o0:(ORshiftLL [8] o1:(ORshiftLL [16] o2:(ORshiftLL [24] o3:(ORshiftLL [32] o4:(ORshiftLL [40] o5:(ORshiftLL [48] s0:(SLLconst [56] y0:(MOVDnop x0:(MOVBUload [i7] {s} p mem))) y1:(MOVDnop x1:(MOVBUload [i6] {s} p mem))) y2:(MOVDnop x2:(MOVBUload [i5] {s} p mem))) y3:(MOVDnop x3:(MOVBUload [i4] {s} p mem))) y4:(MOVDnop x4:(MOVBUload [i3] {s} p mem))) y5:(MOVDnop x5:(MOVBUload [i2] {s} p mem))) y6:(MOVDnop x6:(MOVBUload [i1] {s} p mem)))) // cond: i1 == i0+1 && i2 == i0+2 && i3 == i0+3 && i4 == i0+4 && i5 == i0+5 && i6 == i0+6 && i7 == i0+7 && x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && x4.Uses == 1 && x5.Uses == 1 && x6.Uses == 1 && x7.Uses == 1 && y0.Uses == 1 && y1.Uses == 1 && y2.Uses == 1 && y3.Uses == 1 && y4.Uses == 1 && y5.Uses == 1 && y6.Uses == 1 && y7.Uses == 1 && o0.Uses == 1 && o1.Uses == 1 && o2.Uses == 1 && o3.Uses == 1 && o4.Uses == 1 && o5.Uses == 1 && s0.Uses == 1 && mergePoint(b,x0,x1,x2,x3,x4,x5,x6,x7) != nil && clobber(x0) && clobber(x1) && clobber(x2) && clobber(x3) && clobber(x4) && clobber(x5) && clobber(x6) && clobber(x7) && clobber(y0) && clobber(y1) && clobber(y2) && clobber(y3) && clobber(y4) && clobber(y5) && clobber(y6) && clobber(y7) && clobber(o0) && clobber(o1) && clobber(o2) && clobber(o3) && clobber(o4) && clobber(o5) && clobber(s0) // result: @mergePoint(b,x0,x1,x2,x3,x4,x5,x6,x7) (MOVDload <t> {s} (OffPtr <p.Type> [i0] p) mem) @@ -19733,11 +24303,6 @@ func rewriteValueARM64_OpARM64OR_20(v *Value) bool { v0.AddArg(v1) return true } - return false -} -func rewriteValueARM64_OpARM64OR_30(v *Value) bool { - b := v.Block - _ = b // match: (OR <t> y3:(MOVDnop x3:(MOVBUload [3] {s} p mem)) o0:(ORshiftLL [8] o1:(ORshiftLL [16] s0:(SLLconst [24] y0:(MOVDnop x0:(MOVBUloadidx ptr0 idx0 mem))) y1:(MOVDnop x1:(MOVBUload [1] {s} p1:(ADD ptr1 idx1) mem))) y2:(MOVDnop x2:(MOVBUload [2] {s} p mem)))) // cond: s == nil && x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && y0.Uses == 1 && y1.Uses == 1 && y2.Uses == 1 && y3.Uses == 1 && o0.Uses == 1 && o1.Uses == 1 && s0.Uses == 1 && mergePoint(b,x0,x1,x2,x3) != nil && (isSamePtr(ptr0, ptr1) && isSamePtr(idx0, idx1) || isSamePtr(ptr0, idx1) && isSamePtr(idx0, ptr1)) && isSamePtr(p1, p) && clobber(x0) && clobber(x1) && clobber(x2) && clobber(x3) && clobber(y0) && clobber(y1) && clobber(y2) && clobber(y3) && clobber(o0) && clobber(o1) && clobber(s0) // result: @mergePoint(b,x0,x1,x2,x3) (REVW <t> (MOVWUloadidx <t> ptr0 idx0 mem)) @@ -19986,6 +24551,11 @@ func rewriteValueARM64_OpARM64OR_30(v *Value) bool { v0.AddArg(v1) return true } + return false +} +func rewriteValueARM64_OpARM64OR_40(v *Value) bool { + b := v.Block + _ = b // match: (OR <t> y3:(MOVDnop x3:(MOVBUloadidx ptr (ADDconst [3] idx) mem)) o0:(ORshiftLL [8] o1:(ORshiftLL [16] s0:(SLLconst [24] y0:(MOVDnop x0:(MOVBUloadidx ptr idx mem))) y1:(MOVDnop x1:(MOVBUloadidx ptr (ADDconst [1] idx) mem))) y2:(MOVDnop x2:(MOVBUloadidx ptr (ADDconst [2] idx) mem)))) // cond: x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && y0.Uses == 1 && y1.Uses == 1 && y2.Uses == 1 && y3.Uses == 1 && o0.Uses == 1 && o1.Uses == 1 && s0.Uses == 1 && mergePoint(b,x0,x1,x2,x3) != nil && clobber(x0) && clobber(x1) && clobber(x2) && clobber(x3) && clobber(y0) && clobber(y1) && clobber(y2) && clobber(y3) && clobber(o0) && clobber(o1) && clobber(s0) // result: @mergePoint(b,x0,x1,x2,x3) (REVW <t> (MOVWUloadidx <t> ptr idx mem)) @@ -21834,6 +26404,25 @@ func rewriteValueARM64_OpARM64ORconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (ORconst [c1] (ANDconst [c2] x)) + // cond: c2|c1 == ^0 + // result: (ORconst [c1] x) + for { + c1 := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64ANDconst { + break + } + c2 := v_0.AuxInt + x := v_0.Args[0] + if !(c2|c1 == ^0) { + break + } + v.reset(OpARM64ORconst) + v.AuxInt = c1 + v.AddArg(x) + return true + } return false } func rewriteValueARM64_OpARM64ORshiftLL_0(v *Value) bool { @@ -24183,6 +28772,44 @@ func rewriteValueARM64_OpARM64ORshiftRL_0(v *Value) bool { } return false } +func rewriteValueARM64_OpARM64RORWconst_0(v *Value) bool { + // match: (RORWconst [c] (RORWconst [d] x)) + // cond: + // result: (RORWconst [(c+d)&31] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64RORWconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpARM64RORWconst) + v.AuxInt = (c + d) & 31 + v.AddArg(x) + return true + } + return false +} +func rewriteValueARM64_OpARM64RORconst_0(v *Value) bool { + // match: (RORconst [c] (RORconst [d] x)) + // cond: + // result: (RORconst [(c+d)&63] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpARM64RORconst { + break + } + d := v_0.AuxInt + x := v_0.Args[0] + v.reset(OpARM64RORconst) + v.AuxInt = (c + d) & 63 + v.AddArg(x) + return true + } + return false +} func rewriteValueARM64_OpARM64SLL_0(v *Value) bool { // match: (SLL x (MOVDconst [c])) // cond: @@ -24859,7 +29486,7 @@ func rewriteValueARM64_OpARM64SUB_0(v *Value) bool { return true } // match: (SUB a l:(MUL x y)) - // cond: l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: l.Uses==1 && clobber(l) // result: (MSUB a x y) for { _ = v.Args[1] @@ -24871,7 +29498,7 @@ func rewriteValueARM64_OpARM64SUB_0(v *Value) bool { _ = l.Args[1] x := l.Args[0] y := l.Args[1] - if !(l.Uses == 1 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MSUB) @@ -24881,7 +29508,7 @@ func rewriteValueARM64_OpARM64SUB_0(v *Value) bool { return true } // match: (SUB a l:(MNEG x y)) - // cond: l.Uses==1 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: l.Uses==1 && clobber(l) // result: (MADD a x y) for { _ = v.Args[1] @@ -24893,7 +29520,7 @@ func rewriteValueARM64_OpARM64SUB_0(v *Value) bool { _ = l.Args[1] x := l.Args[0] y := l.Args[1] - if !(l.Uses == 1 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MADD) @@ -24903,7 +29530,7 @@ func rewriteValueARM64_OpARM64SUB_0(v *Value) bool { return true } // match: (SUB a l:(MULW x y)) - // cond: l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: a.Type.Size() != 8 && l.Uses==1 && clobber(l) // result: (MSUBW a x y) for { _ = v.Args[1] @@ -24915,7 +29542,7 @@ func rewriteValueARM64_OpARM64SUB_0(v *Value) bool { _ = l.Args[1] x := l.Args[0] y := l.Args[1] - if !(l.Uses == 1 && a.Type.Size() != 8 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(a.Type.Size() != 8 && l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MSUBW) @@ -24925,7 +29552,7 @@ func rewriteValueARM64_OpARM64SUB_0(v *Value) bool { return true } // match: (SUB a l:(MNEGW x y)) - // cond: l.Uses==1 && a.Type.Size() != 8 && x.Op!=OpARM64MOVDconst && y.Op!=OpARM64MOVDconst && a.Op!=OpARM64MOVDconst && clobber(l) + // cond: a.Type.Size() != 8 && l.Uses==1 && clobber(l) // result: (MADDW a x y) for { _ = v.Args[1] @@ -24937,7 +29564,7 @@ func rewriteValueARM64_OpARM64SUB_0(v *Value) bool { _ = l.Args[1] x := l.Args[0] y := l.Args[1] - if !(l.Uses == 1 && a.Type.Size() != 8 && x.Op != OpARM64MOVDconst && y.Op != OpARM64MOVDconst && a.Op != OpARM64MOVDconst && clobber(l)) { + if !(a.Type.Size() != 8 && l.Uses == 1 && clobber(l)) { break } v.reset(OpARM64MADDW) @@ -25290,6 +29917,132 @@ func rewriteValueARM64_OpARM64TST_0(v *Value) bool { v.AddArg(x) return true } + // match: (TST x0 x1:(SLLconst [c] y)) + // cond: clobberIfDead(x1) + // result: (TSTshiftLL x0 y [c]) + for { + _ = v.Args[1] + x0 := v.Args[0] + x1 := v.Args[1] + if x1.Op != OpARM64SLLconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64TSTshiftLL) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (TST x1:(SLLconst [c] y) x0) + // cond: clobberIfDead(x1) + // result: (TSTshiftLL x0 y [c]) + for { + _ = v.Args[1] + x1 := v.Args[0] + if x1.Op != OpARM64SLLconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + x0 := v.Args[1] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64TSTshiftLL) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (TST x0 x1:(SRLconst [c] y)) + // cond: clobberIfDead(x1) + // result: (TSTshiftRL x0 y [c]) + for { + _ = v.Args[1] + x0 := v.Args[0] + x1 := v.Args[1] + if x1.Op != OpARM64SRLconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64TSTshiftRL) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (TST x1:(SRLconst [c] y) x0) + // cond: clobberIfDead(x1) + // result: (TSTshiftRL x0 y [c]) + for { + _ = v.Args[1] + x1 := v.Args[0] + if x1.Op != OpARM64SRLconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + x0 := v.Args[1] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64TSTshiftRL) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (TST x0 x1:(SRAconst [c] y)) + // cond: clobberIfDead(x1) + // result: (TSTshiftRA x0 y [c]) + for { + _ = v.Args[1] + x0 := v.Args[0] + x1 := v.Args[1] + if x1.Op != OpARM64SRAconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64TSTshiftRA) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } + // match: (TST x1:(SRAconst [c] y) x0) + // cond: clobberIfDead(x1) + // result: (TSTshiftRA x0 y [c]) + for { + _ = v.Args[1] + x1 := v.Args[0] + if x1.Op != OpARM64SRAconst { + break + } + c := x1.AuxInt + y := x1.Args[0] + x0 := v.Args[1] + if !(clobberIfDead(x1)) { + break + } + v.reset(OpARM64TSTshiftRA) + v.AuxInt = c + v.AddArg(x0) + v.AddArg(y) + return true + } return false } func rewriteValueARM64_OpARM64TSTW_0(v *Value) bool { @@ -25429,6 +30182,132 @@ func rewriteValueARM64_OpARM64TSTconst_0(v *Value) bool { } return false } +func rewriteValueARM64_OpARM64TSTshiftLL_0(v *Value) bool { + b := v.Block + _ = b + // match: (TSTshiftLL (MOVDconst [c]) x [d]) + // cond: + // result: (TSTconst [c] (SLLconst <x.Type> x [d])) + for { + d := v.AuxInt + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + v.reset(OpARM64TSTconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64SLLconst, x.Type) + v0.AuxInt = d + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (TSTshiftLL x (MOVDconst [c]) [d]) + // cond: + // result: (TSTconst x [int64(uint64(c)<<uint64(d))]) + for { + d := v.AuxInt + _ = v.Args[1] + x := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v.reset(OpARM64TSTconst) + v.AuxInt = int64(uint64(c) << uint64(d)) + v.AddArg(x) + return true + } + return false +} +func rewriteValueARM64_OpARM64TSTshiftRA_0(v *Value) bool { + b := v.Block + _ = b + // match: (TSTshiftRA (MOVDconst [c]) x [d]) + // cond: + // result: (TSTconst [c] (SRAconst <x.Type> x [d])) + for { + d := v.AuxInt + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + v.reset(OpARM64TSTconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64SRAconst, x.Type) + v0.AuxInt = d + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (TSTshiftRA x (MOVDconst [c]) [d]) + // cond: + // result: (TSTconst x [c>>uint64(d)]) + for { + d := v.AuxInt + _ = v.Args[1] + x := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v.reset(OpARM64TSTconst) + v.AuxInt = c >> uint64(d) + v.AddArg(x) + return true + } + return false +} +func rewriteValueARM64_OpARM64TSTshiftRL_0(v *Value) bool { + b := v.Block + _ = b + // match: (TSTshiftRL (MOVDconst [c]) x [d]) + // cond: + // result: (TSTconst [c] (SRLconst <x.Type> x [d])) + for { + d := v.AuxInt + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64MOVDconst { + break + } + c := v_0.AuxInt + x := v.Args[1] + v.reset(OpARM64TSTconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpARM64SRLconst, x.Type) + v0.AuxInt = d + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (TSTshiftRL x (MOVDconst [c]) [d]) + // cond: + // result: (TSTconst x [int64(uint64(c)>>uint64(d))]) + for { + d := v.AuxInt + _ = v.Args[1] + x := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64MOVDconst { + break + } + c := v_1.AuxInt + v.reset(OpARM64TSTconst) + v.AuxInt = int64(uint64(c) >> uint64(d)) + v.AddArg(x) + return true + } + return false +} func rewriteValueARM64_OpARM64UBFIZ_0(v *Value) bool { // match: (UBFIZ [bfc] (SLLconst [sc] x)) // cond: sc < getARM64BFwidth(bfc) @@ -25950,6 +30829,10 @@ func rewriteValueARM64_OpARM64XOR_0(v *Value) bool { return false } func rewriteValueARM64_OpARM64XOR_10(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (XOR x1:(SRAconst [c] y) x0) // cond: clobberIfDead(x1) // result: (XORshiftRA x0 y [c]) @@ -25971,6 +30854,918 @@ func rewriteValueARM64_OpARM64XOR_10(v *Value) bool { v.AddArg(y) return true } + // match: (XOR (SLL x (ANDconst <t> [63] y)) (CSEL0 <typ.UInt64> {cc} (SRL <typ.UInt64> x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SLL { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 63 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt64 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SRL { + break + } + if v_1_0.Type != typ.UInt64 { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 64 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 63 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 64 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 63 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (XOR (CSEL0 <typ.UInt64> {cc} (SRL <typ.UInt64> x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y)))) (SLL x (ANDconst <t> [63] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt64 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SRL { + break + } + if v_0_0.Type != typ.UInt64 { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 64 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 63 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 64 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 63 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SLL { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 63 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (XOR (SRL <typ.UInt64> x (ANDconst <t> [63] y)) (CSEL0 <typ.UInt64> {cc} (SLL x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SRL { + break + } + if v_0.Type != typ.UInt64 { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 63 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt64 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SLL { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 64 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 63 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 64 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 63 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (XOR (CSEL0 <typ.UInt64> {cc} (SLL x (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y))) (CMPconst [64] (SUB <t> (MOVDconst [64]) (ANDconst <t> [63] y)))) (SRL <typ.UInt64> x (ANDconst <t> [63] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (ROR x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt64 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SLL { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 64 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 63 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 64 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 63 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SRL { + break + } + if v_1.Type != typ.UInt64 { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 63 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64ROR) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (XOR (SLL x (ANDconst <t> [31] y)) (CSEL0 <typ.UInt32> {cc} (SRL <typ.UInt32> (MOVWUreg x) (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SLL { + break + } + _ = v_0.Args[1] + x := v_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 31 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt32 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SRL { + break + } + if v_1_0.Type != typ.UInt32 { + break + } + _ = v_1_0.Args[1] + v_1_0_0 := v_1_0.Args[0] + if v_1_0_0.Op != OpARM64MOVWUreg { + break + } + if x != v_1_0_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 32 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 31 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 32 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 31 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (XOR (CSEL0 <typ.UInt32> {cc} (SRL <typ.UInt32> (MOVWUreg x) (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y)))) (SLL x (ANDconst <t> [31] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x (NEG <t> y)) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt32 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SRL { + break + } + if v_0_0.Type != typ.UInt32 { + break + } + _ = v_0_0.Args[1] + v_0_0_0 := v_0_0.Args[0] + if v_0_0_0.Op != OpARM64MOVWUreg { + break + } + x := v_0_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 32 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 31 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 32 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 31 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SLL { + break + } + _ = v_1.Args[1] + if x != v_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 31 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, t) + v0.AddArg(y) + v.AddArg(v0) + return true + } + // match: (XOR (SRL <typ.UInt32> (MOVWUreg x) (ANDconst <t> [31] y)) (CSEL0 <typ.UInt32> {cc} (SLL x (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64SRL { + break + } + if v_0.Type != typ.UInt32 { + break + } + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64MOVWUreg { + break + } + x := v_0_0.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64ANDconst { + break + } + t := v_0_1.Type + if v_0_1.AuxInt != 31 { + break + } + y := v_0_1.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpARM64CSEL0 { + break + } + if v_1.Type != typ.UInt32 { + break + } + cc := v_1.Aux + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64SLL { + break + } + _ = v_1_0.Args[1] + if x != v_1_0.Args[0] { + break + } + v_1_0_1 := v_1_0.Args[1] + if v_1_0_1.Op != OpARM64SUB { + break + } + if v_1_0_1.Type != t { + break + } + _ = v_1_0_1.Args[1] + v_1_0_1_0 := v_1_0_1.Args[0] + if v_1_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_1_0_1_0.AuxInt != 32 { + break + } + v_1_0_1_1 := v_1_0_1.Args[1] + if v_1_0_1_1.Op != OpARM64ANDconst { + break + } + if v_1_0_1_1.Type != t { + break + } + if v_1_0_1_1.AuxInt != 31 { + break + } + if y != v_1_0_1_1.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64CMPconst { + break + } + if v_1_1.AuxInt != 64 { + break + } + v_1_1_0 := v_1_1.Args[0] + if v_1_1_0.Op != OpARM64SUB { + break + } + if v_1_1_0.Type != t { + break + } + _ = v_1_1_0.Args[1] + v_1_1_0_0 := v_1_1_0.Args[0] + if v_1_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_1_1_0_0.AuxInt != 32 { + break + } + v_1_1_0_1 := v_1_1_0.Args[1] + if v_1_1_0_1.Op != OpARM64ANDconst { + break + } + if v_1_1_0_1.Type != t { + break + } + if v_1_1_0_1.AuxInt != 31 { + break + } + if y != v_1_1_0_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (XOR (CSEL0 <typ.UInt32> {cc} (SLL x (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y))) (CMPconst [64] (SUB <t> (MOVDconst [32]) (ANDconst <t> [31] y)))) (SRL <typ.UInt32> (MOVWUreg x) (ANDconst <t> [31] y))) + // cond: cc.(Op) == OpARM64LessThanU + // result: (RORW x y) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpARM64CSEL0 { + break + } + if v_0.Type != typ.UInt32 { + break + } + cc := v_0.Aux + _ = v_0.Args[1] + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpARM64SLL { + break + } + _ = v_0_0.Args[1] + x := v_0_0.Args[0] + v_0_0_1 := v_0_0.Args[1] + if v_0_0_1.Op != OpARM64SUB { + break + } + t := v_0_0_1.Type + _ = v_0_0_1.Args[1] + v_0_0_1_0 := v_0_0_1.Args[0] + if v_0_0_1_0.Op != OpARM64MOVDconst { + break + } + if v_0_0_1_0.AuxInt != 32 { + break + } + v_0_0_1_1 := v_0_0_1.Args[1] + if v_0_0_1_1.Op != OpARM64ANDconst { + break + } + if v_0_0_1_1.Type != t { + break + } + if v_0_0_1_1.AuxInt != 31 { + break + } + y := v_0_0_1_1.Args[0] + v_0_1 := v_0.Args[1] + if v_0_1.Op != OpARM64CMPconst { + break + } + if v_0_1.AuxInt != 64 { + break + } + v_0_1_0 := v_0_1.Args[0] + if v_0_1_0.Op != OpARM64SUB { + break + } + if v_0_1_0.Type != t { + break + } + _ = v_0_1_0.Args[1] + v_0_1_0_0 := v_0_1_0.Args[0] + if v_0_1_0_0.Op != OpARM64MOVDconst { + break + } + if v_0_1_0_0.AuxInt != 32 { + break + } + v_0_1_0_1 := v_0_1_0.Args[1] + if v_0_1_0_1.Op != OpARM64ANDconst { + break + } + if v_0_1_0_1.Type != t { + break + } + if v_0_1_0_1.AuxInt != 31 { + break + } + if y != v_0_1_0_1.Args[0] { + break + } + v_1 := v.Args[1] + if v_1.Op != OpARM64SRL { + break + } + if v_1.Type != typ.UInt32 { + break + } + _ = v_1.Args[1] + v_1_0 := v_1.Args[0] + if v_1_0.Op != OpARM64MOVWUreg { + break + } + if x != v_1_0.Args[0] { + break + } + v_1_1 := v_1.Args[1] + if v_1_1.Op != OpARM64ANDconst { + break + } + if v_1_1.Type != t { + break + } + if v_1_1.AuxInt != 31 { + break + } + if y != v_1_1.Args[0] { + break + } + if !(cc.(Op) == OpARM64LessThanU) { + break + } + v.reset(OpARM64RORW) + v.AddArg(x) + v.AddArg(y) + return true + } return false } func rewriteValueARM64_OpARM64XORconst_0(v *Value) bool { @@ -26365,6 +32160,17 @@ func rewriteValueARM64_OpARM64XORshiftRL_0(v *Value) bool { } return false } +func rewriteValueARM64_OpAbs_0(v *Value) bool { + // match: (Abs x) + // cond: + // result: (FABSD x) + for { + x := v.Args[0] + v.reset(OpARM64FABSD) + v.AddArg(x) + return true + } +} func rewriteValueARM64_OpAdd16_0(v *Value) bool { // match: (Add16 x y) // cond: @@ -30489,6 +36295,42 @@ func rewriteValueARM64_OpPopCount64_0(v *Value) bool { return true } } +func rewriteValueARM64_OpRotateLeft32_0(v *Value) bool { + b := v.Block + _ = b + // match: (RotateLeft32 x y) + // cond: + // result: (RORW x (NEG <y.Type> y)) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + v.reset(OpARM64RORW) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, y.Type) + v0.AddArg(y) + v.AddArg(v0) + return true + } +} +func rewriteValueARM64_OpRotateLeft64_0(v *Value) bool { + b := v.Block + _ = b + // match: (RotateLeft64 x y) + // cond: + // result: (ROR x (NEG <y.Type> y)) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + v.reset(OpARM64ROR) + v.AddArg(x) + v0 := b.NewValue0(v.Pos, OpARM64NEG, y.Type) + v0.AddArg(y) + v.AddArg(v0) + return true + } +} func rewriteValueARM64_OpRound_0(v *Value) bool { // match: (Round x) // cond: @@ -30522,6 +36364,17 @@ func rewriteValueARM64_OpRound64F_0(v *Value) bool { return true } } +func rewriteValueARM64_OpRoundToEven_0(v *Value) bool { + // match: (RoundToEven x) + // cond: + // result: (FRINTND x) + for { + x := v.Args[0] + v.reset(OpARM64FRINTND) + v.AddArg(x) + return true + } +} func rewriteValueARM64_OpRsh16Ux16_0(v *Value) bool { b := v.Block _ = b diff --git a/src/cmd/compile/internal/ssa/rewritePPC64.go b/src/cmd/compile/internal/ssa/rewritePPC64.go index ba6a862989..9aff3106db 100644 --- a/src/cmd/compile/internal/ssa/rewritePPC64.go +++ b/src/cmd/compile/internal/ssa/rewritePPC64.go @@ -337,6 +337,8 @@ func rewriteValuePPC64(v *Value) bool { return rewriteValuePPC64_OpMul64_0(v) case OpMul64F: return rewriteValuePPC64_OpMul64F_0(v) + case OpMul64uhilo: + return rewriteValuePPC64_OpMul64uhilo_0(v) case OpMul8: return rewriteValuePPC64_OpMul8_0(v) case OpNeg16: @@ -388,9 +390,9 @@ func rewriteValuePPC64(v *Value) bool { case OpPPC64ADDconst: return rewriteValuePPC64_OpPPC64ADDconst_0(v) case OpPPC64AND: - return rewriteValuePPC64_OpPPC64AND_0(v) + return rewriteValuePPC64_OpPPC64AND_0(v) || rewriteValuePPC64_OpPPC64AND_10(v) case OpPPC64ANDconst: - return rewriteValuePPC64_OpPPC64ANDconst_0(v) + return rewriteValuePPC64_OpPPC64ANDconst_0(v) || rewriteValuePPC64_OpPPC64ANDconst_10(v) case OpPPC64CMP: return rewriteValuePPC64_OpPPC64CMP_0(v) case OpPPC64CMPU: @@ -449,46 +451,66 @@ func rewriteValuePPC64(v *Value) bool { return rewriteValuePPC64_OpPPC64MFVSRD_0(v) case OpPPC64MOVBZload: return rewriteValuePPC64_OpPPC64MOVBZload_0(v) + case OpPPC64MOVBZloadidx: + return rewriteValuePPC64_OpPPC64MOVBZloadidx_0(v) case OpPPC64MOVBZreg: - return rewriteValuePPC64_OpPPC64MOVBZreg_0(v) + return rewriteValuePPC64_OpPPC64MOVBZreg_0(v) || rewriteValuePPC64_OpPPC64MOVBZreg_10(v) case OpPPC64MOVBreg: - return rewriteValuePPC64_OpPPC64MOVBreg_0(v) + return rewriteValuePPC64_OpPPC64MOVBreg_0(v) || rewriteValuePPC64_OpPPC64MOVBreg_10(v) case OpPPC64MOVBstore: return rewriteValuePPC64_OpPPC64MOVBstore_0(v) || rewriteValuePPC64_OpPPC64MOVBstore_10(v) || rewriteValuePPC64_OpPPC64MOVBstore_20(v) + case OpPPC64MOVBstoreidx: + return rewriteValuePPC64_OpPPC64MOVBstoreidx_0(v) || rewriteValuePPC64_OpPPC64MOVBstoreidx_10(v) case OpPPC64MOVBstorezero: return rewriteValuePPC64_OpPPC64MOVBstorezero_0(v) case OpPPC64MOVDload: return rewriteValuePPC64_OpPPC64MOVDload_0(v) + case OpPPC64MOVDloadidx: + return rewriteValuePPC64_OpPPC64MOVDloadidx_0(v) case OpPPC64MOVDstore: return rewriteValuePPC64_OpPPC64MOVDstore_0(v) + case OpPPC64MOVDstoreidx: + return rewriteValuePPC64_OpPPC64MOVDstoreidx_0(v) case OpPPC64MOVDstorezero: return rewriteValuePPC64_OpPPC64MOVDstorezero_0(v) case OpPPC64MOVHBRstore: return rewriteValuePPC64_OpPPC64MOVHBRstore_0(v) case OpPPC64MOVHZload: return rewriteValuePPC64_OpPPC64MOVHZload_0(v) + case OpPPC64MOVHZloadidx: + return rewriteValuePPC64_OpPPC64MOVHZloadidx_0(v) case OpPPC64MOVHZreg: - return rewriteValuePPC64_OpPPC64MOVHZreg_0(v) + return rewriteValuePPC64_OpPPC64MOVHZreg_0(v) || rewriteValuePPC64_OpPPC64MOVHZreg_10(v) case OpPPC64MOVHload: return rewriteValuePPC64_OpPPC64MOVHload_0(v) + case OpPPC64MOVHloadidx: + return rewriteValuePPC64_OpPPC64MOVHloadidx_0(v) case OpPPC64MOVHreg: - return rewriteValuePPC64_OpPPC64MOVHreg_0(v) + return rewriteValuePPC64_OpPPC64MOVHreg_0(v) || rewriteValuePPC64_OpPPC64MOVHreg_10(v) case OpPPC64MOVHstore: return rewriteValuePPC64_OpPPC64MOVHstore_0(v) + case OpPPC64MOVHstoreidx: + return rewriteValuePPC64_OpPPC64MOVHstoreidx_0(v) case OpPPC64MOVHstorezero: return rewriteValuePPC64_OpPPC64MOVHstorezero_0(v) case OpPPC64MOVWBRstore: return rewriteValuePPC64_OpPPC64MOVWBRstore_0(v) case OpPPC64MOVWZload: return rewriteValuePPC64_OpPPC64MOVWZload_0(v) + case OpPPC64MOVWZloadidx: + return rewriteValuePPC64_OpPPC64MOVWZloadidx_0(v) case OpPPC64MOVWZreg: - return rewriteValuePPC64_OpPPC64MOVWZreg_0(v) + return rewriteValuePPC64_OpPPC64MOVWZreg_0(v) || rewriteValuePPC64_OpPPC64MOVWZreg_10(v) || rewriteValuePPC64_OpPPC64MOVWZreg_20(v) case OpPPC64MOVWload: return rewriteValuePPC64_OpPPC64MOVWload_0(v) + case OpPPC64MOVWloadidx: + return rewriteValuePPC64_OpPPC64MOVWloadidx_0(v) case OpPPC64MOVWreg: - return rewriteValuePPC64_OpPPC64MOVWreg_0(v) + return rewriteValuePPC64_OpPPC64MOVWreg_0(v) || rewriteValuePPC64_OpPPC64MOVWreg_10(v) case OpPPC64MOVWstore: return rewriteValuePPC64_OpPPC64MOVWstore_0(v) + case OpPPC64MOVWstoreidx: + return rewriteValuePPC64_OpPPC64MOVWstoreidx_0(v) case OpPPC64MOVWstorezero: return rewriteValuePPC64_OpPPC64MOVWstorezero_0(v) case OpPPC64MTVSRD: @@ -544,7 +566,7 @@ func rewriteValuePPC64(v *Value) bool { case OpRsh32Ux32: return rewriteValuePPC64_OpRsh32Ux32_0(v) case OpRsh32Ux64: - return rewriteValuePPC64_OpRsh32Ux64_0(v) + return rewriteValuePPC64_OpRsh32Ux64_0(v) || rewriteValuePPC64_OpRsh32Ux64_10(v) case OpRsh32Ux8: return rewriteValuePPC64_OpRsh32Ux8_0(v) case OpRsh32x16: @@ -552,7 +574,7 @@ func rewriteValuePPC64(v *Value) bool { case OpRsh32x32: return rewriteValuePPC64_OpRsh32x32_0(v) case OpRsh32x64: - return rewriteValuePPC64_OpRsh32x64_0(v) + return rewriteValuePPC64_OpRsh32x64_0(v) || rewriteValuePPC64_OpRsh32x64_10(v) case OpRsh32x8: return rewriteValuePPC64_OpRsh32x8_0(v) case OpRsh64Ux16: @@ -560,7 +582,7 @@ func rewriteValuePPC64(v *Value) bool { case OpRsh64Ux32: return rewriteValuePPC64_OpRsh64Ux32_0(v) case OpRsh64Ux64: - return rewriteValuePPC64_OpRsh64Ux64_0(v) + return rewriteValuePPC64_OpRsh64Ux64_0(v) || rewriteValuePPC64_OpRsh64Ux64_10(v) case OpRsh64Ux8: return rewriteValuePPC64_OpRsh64Ux8_0(v) case OpRsh64x16: @@ -568,7 +590,7 @@ func rewriteValuePPC64(v *Value) bool { case OpRsh64x32: return rewriteValuePPC64_OpRsh64x32_0(v) case OpRsh64x64: - return rewriteValuePPC64_OpRsh64x64_0(v) + return rewriteValuePPC64_OpRsh64x64_0(v) || rewriteValuePPC64_OpRsh64x64_10(v) case OpRsh64x8: return rewriteValuePPC64_OpRsh64x8_0(v) case OpRsh8Ux16: @@ -3070,6 +3092,21 @@ func rewriteValuePPC64_OpLsh16x16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Lsh16x16 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh16x16 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt16to64 y))))) for { @@ -3136,6 +3173,21 @@ func rewriteValuePPC64_OpLsh16x32_0(v *Value) bool { return true } // match: (Lsh16x32 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh16x32 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt32to64 y))))) for { @@ -3219,6 +3271,21 @@ func rewriteValuePPC64_OpLsh16x64_0(v *Value) bool { return true } // match: (Lsh16x64 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh16x64 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] y)))) for { @@ -3245,6 +3312,21 @@ func rewriteValuePPC64_OpLsh16x8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Lsh16x8 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh16x8 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt8to64 y))))) for { @@ -3273,6 +3355,21 @@ func rewriteValuePPC64_OpLsh32x16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Lsh32x16 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh32x16 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt16to64 y))))) for { @@ -3339,6 +3436,21 @@ func rewriteValuePPC64_OpLsh32x32_0(v *Value) bool { return true } // match: (Lsh32x32 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh32x32 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt32to64 y))))) for { @@ -3421,6 +3533,21 @@ func rewriteValuePPC64_OpLsh32x64_0(v *Value) bool { v.AddArg(x) return true } + // match: (Lsh32x64 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } // match: (Lsh32x64 x (AND y (MOVDconst [31]))) // cond: // result: (SLW x (ANDconst <typ.Int32> [31] y)) @@ -3527,6 +3654,21 @@ func rewriteValuePPC64_OpLsh32x8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Lsh32x8 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh32x8 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt8to64 y))))) for { @@ -3555,6 +3697,21 @@ func rewriteValuePPC64_OpLsh64x16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Lsh64x16 x y) + // cond: shiftIsBounded(v) + // result: (SLD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh64x16 x y) // cond: // result: (SLD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt16to64 y))))) for { @@ -3621,6 +3778,21 @@ func rewriteValuePPC64_OpLsh64x32_0(v *Value) bool { return true } // match: (Lsh64x32 x y) + // cond: shiftIsBounded(v) + // result: (SLD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh64x32 x y) // cond: // result: (SLD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt32to64 y))))) for { @@ -3703,6 +3875,21 @@ func rewriteValuePPC64_OpLsh64x64_0(v *Value) bool { v.AddArg(x) return true } + // match: (Lsh64x64 x y) + // cond: shiftIsBounded(v) + // result: (SLD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLD) + v.AddArg(x) + v.AddArg(y) + return true + } // match: (Lsh64x64 x (AND y (MOVDconst [63]))) // cond: // result: (SLD x (ANDconst <typ.Int64> [63] y)) @@ -3809,6 +3996,21 @@ func rewriteValuePPC64_OpLsh64x8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Lsh64x8 x y) + // cond: shiftIsBounded(v) + // result: (SLD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh64x8 x y) // cond: // result: (SLD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt8to64 y))))) for { @@ -3837,6 +4039,21 @@ func rewriteValuePPC64_OpLsh8x16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Lsh8x16 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh8x16 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt16to64 y))))) for { @@ -3903,6 +4120,21 @@ func rewriteValuePPC64_OpLsh8x32_0(v *Value) bool { return true } // match: (Lsh8x32 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh8x32 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt32to64 y))))) for { @@ -3986,6 +4218,21 @@ func rewriteValuePPC64_OpLsh8x64_0(v *Value) bool { return true } // match: (Lsh8x64 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh8x64 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] y)))) for { @@ -4012,6 +4259,21 @@ func rewriteValuePPC64_OpLsh8x8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Lsh8x8 x y) + // cond: shiftIsBounded(v) + // result: (SLW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SLW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Lsh8x8 x y) // cond: // result: (SLW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt8to64 y))))) for { @@ -4569,6 +4831,20 @@ func rewriteValuePPC64_OpMul64F_0(v *Value) bool { return true } } +func rewriteValuePPC64_OpMul64uhilo_0(v *Value) bool { + // match: (Mul64uhilo x y) + // cond: + // result: (LoweredMuluhilo x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + v.reset(OpPPC64LoweredMuluhilo) + v.AddArg(x) + v.AddArg(y) + return true + } +} func rewriteValuePPC64_OpMul8_0(v *Value) bool { // match: (Mul8 x y) // cond: @@ -5533,6 +5809,95 @@ func rewriteValuePPC64_OpPPC64AND_0(v *Value) bool { v.AddArg(x) return true } + // match: (AND (MOVDconst [c]) y:(MOVWZreg _)) + // cond: c&0xFFFFFFFF == 0xFFFFFFFF + // result: y + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + y := v.Args[1] + if y.Op != OpPPC64MOVWZreg { + break + } + if !(c&0xFFFFFFFF == 0xFFFFFFFF) { + break + } + v.reset(OpCopy) + v.Type = y.Type + v.AddArg(y) + return true + } + // match: (AND y:(MOVWZreg _) (MOVDconst [c])) + // cond: c&0xFFFFFFFF == 0xFFFFFFFF + // result: y + for { + _ = v.Args[1] + y := v.Args[0] + if y.Op != OpPPC64MOVWZreg { + break + } + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + if !(c&0xFFFFFFFF == 0xFFFFFFFF) { + break + } + v.reset(OpCopy) + v.Type = y.Type + v.AddArg(y) + return true + } + // match: (AND (MOVDconst [0xFFFFFFFF]) y:(MOVWreg x)) + // cond: + // result: (MOVWZreg x) + for { + _ = v.Args[1] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + if v_0.AuxInt != 0xFFFFFFFF { + break + } + y := v.Args[1] + if y.Op != OpPPC64MOVWreg { + break + } + x := y.Args[0] + v.reset(OpPPC64MOVWZreg) + v.AddArg(x) + return true + } + // match: (AND y:(MOVWreg x) (MOVDconst [0xFFFFFFFF])) + // cond: + // result: (MOVWZreg x) + for { + _ = v.Args[1] + y := v.Args[0] + if y.Op != OpPPC64MOVWreg { + break + } + x := y.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + if v_1.AuxInt != 0xFFFFFFFF { + break + } + v.reset(OpPPC64MOVWZreg) + v.AddArg(x) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64AND_10(v *Value) bool { // match: (AND (MOVDconst [c]) x:(MOVBZload _ _)) // cond: // result: (ANDconst [c&0xFF] x) @@ -5673,6 +6038,22 @@ func rewriteValuePPC64_OpPPC64ANDconst_0(v *Value) bool { v.AddArg(y) return true } + // match: (ANDconst [0xFF] y:(MOVBreg _)) + // cond: + // result: y + for { + if v.AuxInt != 0xFF { + break + } + y := v.Args[0] + if y.Op != OpPPC64MOVBreg { + break + } + v.reset(OpCopy) + v.Type = y.Type + v.AddArg(y) + return true + } // match: (ANDconst [c] y:(MOVHZreg _)) // cond: c&0xFFFF == 0xFFFF // result: y @@ -5690,16 +6071,15 @@ func rewriteValuePPC64_OpPPC64ANDconst_0(v *Value) bool { v.AddArg(y) return true } - // match: (ANDconst [c] y:(MOVWZreg _)) - // cond: c&0xFFFFFFFF == 0xFFFFFFFF + // match: (ANDconst [0xFFFF] y:(MOVHreg _)) + // cond: // result: y for { - c := v.AuxInt - y := v.Args[0] - if y.Op != OpPPC64MOVWZreg { + if v.AuxInt != 0xFFFF { break } - if !(c&0xFFFFFFFF == 0xFFFFFFFF) { + y := v.Args[0] + if y.Op != OpPPC64MOVHreg { break } v.reset(OpCopy) @@ -5707,6 +6087,21 @@ func rewriteValuePPC64_OpPPC64ANDconst_0(v *Value) bool { v.AddArg(y) return true } + // match: (ANDconst [c] (MOVBreg x)) + // cond: + // result: (ANDconst [c&0xFF] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVBreg { + break + } + x := v_0.Args[0] + v.reset(OpPPC64ANDconst) + v.AuxInt = c & 0xFF + v.AddArg(x) + return true + } // match: (ANDconst [c] (MOVBZreg x)) // cond: // result: (ANDconst [c&0xFF] x) @@ -5722,6 +6117,24 @@ func rewriteValuePPC64_OpPPC64ANDconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (ANDconst [c] (MOVHreg x)) + // cond: + // result: (ANDconst [c&0xFFFF] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVHreg { + break + } + x := v_0.Args[0] + v.reset(OpPPC64ANDconst) + v.AuxInt = c & 0xFFFF + v.AddArg(x) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64ANDconst_10(v *Value) bool { // match: (ANDconst [c] (MOVHZreg x)) // cond: // result: (ANDconst [c&0xFFFF] x) @@ -5737,6 +6150,21 @@ func rewriteValuePPC64_OpPPC64ANDconst_0(v *Value) bool { v.AddArg(x) return true } + // match: (ANDconst [c] (MOVWreg x)) + // cond: + // result: (ANDconst [c&0xFFFFFFFF] x) + for { + c := v.AuxInt + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVWreg { + break + } + x := v_0.Args[0] + v.reset(OpPPC64ANDconst) + v.AuxInt = c & 0xFFFFFFFF + v.AddArg(x) + return true + } // match: (ANDconst [c] (MOVWZreg x)) // cond: // result: (ANDconst [c&0xFFFFFFFF] x) @@ -6257,7 +6685,7 @@ func rewriteValuePPC64_OpPPC64Equal_0(v *Value) bool { func rewriteValuePPC64_OpPPC64FABS_0(v *Value) bool { // match: (FABS (FMOVDconst [x])) // cond: - // result: (FMOVDconst [f2i(math.Abs(i2f(x)))]) + // result: (FMOVDconst [auxFrom64F(math.Abs(auxTo64F(x)))]) for { v_0 := v.Args[0] if v_0.Op != OpPPC64FMOVDconst { @@ -6265,7 +6693,7 @@ func rewriteValuePPC64_OpPPC64FABS_0(v *Value) bool { } x := v_0.AuxInt v.reset(OpPPC64FMOVDconst) - v.AuxInt = f2i(math.Abs(i2f(x))) + v.AuxInt = auxFrom64F(math.Abs(auxTo64F(x))) return true } return false @@ -6355,7 +6783,7 @@ func rewriteValuePPC64_OpPPC64FADDS_0(v *Value) bool { func rewriteValuePPC64_OpPPC64FCEIL_0(v *Value) bool { // match: (FCEIL (FMOVDconst [x])) // cond: - // result: (FMOVDconst [f2i(math.Ceil(i2f(x)))]) + // result: (FMOVDconst [auxFrom64F(math.Ceil(auxTo64F(x)))]) for { v_0 := v.Args[0] if v_0.Op != OpPPC64FMOVDconst { @@ -6363,7 +6791,7 @@ func rewriteValuePPC64_OpPPC64FCEIL_0(v *Value) bool { } x := v_0.AuxInt v.reset(OpPPC64FMOVDconst) - v.AuxInt = f2i(math.Ceil(i2f(x))) + v.AuxInt = auxFrom64F(math.Ceil(auxTo64F(x))) return true } return false @@ -6371,7 +6799,7 @@ func rewriteValuePPC64_OpPPC64FCEIL_0(v *Value) bool { func rewriteValuePPC64_OpPPC64FFLOOR_0(v *Value) bool { // match: (FFLOOR (FMOVDconst [x])) // cond: - // result: (FMOVDconst [f2i(math.Floor(i2f(x)))]) + // result: (FMOVDconst [auxFrom64F(math.Floor(auxTo64F(x)))]) for { v_0 := v.Args[0] if v_0.Op != OpPPC64FMOVDconst { @@ -6379,7 +6807,7 @@ func rewriteValuePPC64_OpPPC64FFLOOR_0(v *Value) bool { } x := v_0.AuxInt v.reset(OpPPC64FMOVDconst) - v.AuxInt = f2i(math.Floor(i2f(x))) + v.AuxInt = auxFrom64F(math.Floor(auxTo64F(x))) return true } return false @@ -6681,7 +7109,7 @@ func rewriteValuePPC64_OpPPC64FNEG_0(v *Value) bool { func rewriteValuePPC64_OpPPC64FSQRT_0(v *Value) bool { // match: (FSQRT (FMOVDconst [x])) // cond: - // result: (FMOVDconst [f2i(math.Sqrt(i2f(x)))]) + // result: (FMOVDconst [auxFrom64F(math.Sqrt(auxTo64F(x)))]) for { v_0 := v.Args[0] if v_0.Op != OpPPC64FMOVDconst { @@ -6689,7 +7117,7 @@ func rewriteValuePPC64_OpPPC64FSQRT_0(v *Value) bool { } x := v_0.AuxInt v.reset(OpPPC64FMOVDconst) - v.AuxInt = f2i(math.Sqrt(i2f(x))) + v.AuxInt = auxFrom64F(math.Sqrt(auxTo64F(x))) return true } return false @@ -6741,7 +7169,7 @@ func rewriteValuePPC64_OpPPC64FSUBS_0(v *Value) bool { func rewriteValuePPC64_OpPPC64FTRUNC_0(v *Value) bool { // match: (FTRUNC (FMOVDconst [x])) // cond: - // result: (FMOVDconst [f2i(math.Trunc(i2f(x)))]) + // result: (FMOVDconst [auxFrom64F(math.Trunc(auxTo64F(x)))]) for { v_0 := v.Args[0] if v_0.Op != OpPPC64FMOVDconst { @@ -6749,7 +7177,7 @@ func rewriteValuePPC64_OpPPC64FTRUNC_0(v *Value) bool { } x := v_0.AuxInt v.reset(OpPPC64FMOVDconst) - v.AuxInt = f2i(math.Trunc(i2f(x))) + v.AuxInt = auxFrom64F(math.Trunc(auxTo64F(x))) return true } return false @@ -7058,9 +7486,84 @@ func rewriteValuePPC64_OpPPC64MOVBZload_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVBZload [0] {sym} p:(ADD ptr idx) mem) + // cond: sym == nil && p.Uses == 1 + // result: (MOVBZloadidx ptr idx mem) + for { + if v.AuxInt != 0 { + break + } + sym := v.Aux + _ = v.Args[1] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + mem := v.Args[1] + if !(sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVBZloadidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(mem) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVBZloadidx_0(v *Value) bool { + // match: (MOVBZloadidx ptr (MOVDconst [c]) mem) + // cond: is16Bit(c) + // result: (MOVBZload [c] ptr mem) + for { + _ = v.Args[2] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVBZload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVBZloadidx (MOVDconst [c]) ptr mem) + // cond: is16Bit(c) + // result: (MOVBZload [c] ptr mem) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVBZload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVBZreg_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (MOVBZreg y:(ANDconst [c] _)) // cond: uint64(c) <= 0xFF // result: y @@ -7078,6 +7581,81 @@ func rewriteValuePPC64_OpPPC64MOVBZreg_0(v *Value) bool { v.AddArg(y) return true } + // match: (MOVBZreg (SRWconst [c] (MOVBZreg x))) + // cond: + // result: (SRWconst [c] (MOVBZreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVBZreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVBZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVBZreg (SRWconst [c] x)) + // cond: sizeof(x.Type) == 8 + // result: (SRWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(sizeof(x.Type) == 8) { + break + } + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVBZreg (SRDconst [c] x)) + // cond: c>=56 + // result: (SRDconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c >= 56) { + break + } + v.reset(OpPPC64SRDconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVBZreg (SRWconst [c] x)) + // cond: c>=24 + // result: (SRWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c >= 24) { + break + } + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v.AddArg(x) + return true + } // match: (MOVBZreg y:(MOVBZreg _)) // cond: // result: y @@ -7118,6 +7696,40 @@ func rewriteValuePPC64_OpPPC64MOVBZreg_0(v *Value) bool { v.AddArg(x) return true } + // match: (MOVBZreg x:(MOVBZloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVBZloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVBZreg x:(Arg <t>)) + // cond: is8BitInt(t) && !isSigned(t) + // result: x + for { + x := v.Args[0] + if x.Op != OpArg { + break + } + t := x.Type + if !(is8BitInt(t) && !isSigned(t)) { + break + } + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVBZreg_10(v *Value) bool { // match: (MOVBZreg (MOVDconst [c])) // cond: // result: (MOVDconst [int64(uint8(c))]) @@ -7134,6 +7746,10 @@ func rewriteValuePPC64_OpPPC64MOVBZreg_0(v *Value) bool { return false } func rewriteValuePPC64_OpPPC64MOVBreg_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (MOVBreg y:(ANDconst [c] _)) // cond: uint64(c) <= 0x7F // result: y @@ -7151,6 +7767,117 @@ func rewriteValuePPC64_OpPPC64MOVBreg_0(v *Value) bool { v.AddArg(y) return true } + // match: (MOVBreg (SRAWconst [c] (MOVBreg x))) + // cond: + // result: (SRAWconst [c] (MOVBreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVBreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVBreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVBreg (SRAWconst [c] x)) + // cond: sizeof(x.Type) == 8 + // result: (SRAWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(sizeof(x.Type) == 8) { + break + } + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVBreg (SRDconst [c] x)) + // cond: c>56 + // result: (SRDconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c > 56) { + break + } + v.reset(OpPPC64SRDconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVBreg (SRDconst [c] x)) + // cond: c==56 + // result: (SRADconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c == 56) { + break + } + v.reset(OpPPC64SRADconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVBreg (SRWconst [c] x)) + // cond: c>24 + // result: (SRWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c > 24) { + break + } + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVBreg (SRWconst [c] x)) + // cond: c==24 + // result: (SRAWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c == 24) { + break + } + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v.AddArg(x) + return true + } // match: (MOVBreg y:(MOVBreg _)) // cond: // result: y @@ -7177,6 +7904,26 @@ func rewriteValuePPC64_OpPPC64MOVBreg_0(v *Value) bool { v.AddArg(x) return true } + // match: (MOVBreg x:(Arg <t>)) + // cond: is8BitInt(t) && isSigned(t) + // result: x + for { + x := v.Args[0] + if x.Op != OpArg { + break + } + t := x.Type + if !(is8BitInt(t) && isSigned(t)) { + break + } + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVBreg_10(v *Value) bool { // match: (MOVBreg (MOVDconst [c])) // cond: // result: (MOVDconst [int64(int8(c))]) @@ -7193,10 +7940,6 @@ func rewriteValuePPC64_OpPPC64MOVBreg_0(v *Value) bool { return false } func rewriteValuePPC64_OpPPC64MOVBstore_0(v *Value) bool { - b := v.Block - _ = b - typ := &b.Func.Config.Types - _ = typ // match: (MOVBstore [off1] {sym} (ADDconst [off2] x) val mem) // cond: is16Bit(off1+off2) // result: (MOVBstore [off1+off2] {sym} x val mem) @@ -7250,8 +7993,8 @@ func rewriteValuePPC64_OpPPC64MOVBstore_0(v *Value) bool { v.AddArg(mem) return true } - // match: (MOVBstore [off] {sym} ptr (MOVDconst [c]) mem) - // cond: c == 0 + // match: (MOVBstore [off] {sym} ptr (MOVDconst [0]) mem) + // cond: // result: (MOVBstorezero [off] {sym} ptr mem) for { off := v.AuxInt @@ -7262,11 +8005,10 @@ func rewriteValuePPC64_OpPPC64MOVBstore_0(v *Value) bool { if v_1.Op != OpPPC64MOVDconst { break } - c := v_1.AuxInt - mem := v.Args[2] - if !(c == 0) { + if v_1.AuxInt != 0 { break } + mem := v.Args[2] v.reset(OpPPC64MOVBstorezero) v.AuxInt = off v.Aux = sym @@ -7274,6 +8016,32 @@ func rewriteValuePPC64_OpPPC64MOVBstore_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVBstore [off] {sym} p:(ADD ptr idx) val mem) + // cond: off == 0 && sym == nil && p.Uses == 1 + // result: (MOVBstoreidx ptr idx val mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + val := v.Args[1] + mem := v.Args[2] + if !(off == 0 && sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVBstoreidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (MOVBstore [off] {sym} ptr (MOVBreg x) mem) // cond: // result: (MOVBstore [off] {sym} ptr x mem) @@ -7406,6 +8174,15 @@ func rewriteValuePPC64_OpPPC64MOVBstore_0(v *Value) bool { v.AddArg(mem) return true } + return false +} +func rewriteValuePPC64_OpPPC64MOVBstore_10(v *Value) bool { + b := v.Block + _ = b + config := b.Func.Config + _ = config + typ := &b.Func.Config.Types + _ = typ // match: (MOVBstore [off] {sym} ptr (SRWconst (MOVHreg x) [c]) mem) // cond: c <= 8 // result: (MOVBstore [off] {sym} ptr (SRWconst <typ.UInt32> x [c]) mem) @@ -7439,15 +8216,6 @@ func rewriteValuePPC64_OpPPC64MOVBstore_0(v *Value) bool { v.AddArg(mem) return true } - return false -} -func rewriteValuePPC64_OpPPC64MOVBstore_10(v *Value) bool { - b := v.Block - _ = b - config := b.Func.Config - _ = config - typ := &b.Func.Config.Types - _ = typ // match: (MOVBstore [off] {sym} ptr (SRWconst (MOVHZreg x) [c]) mem) // cond: c <= 8 // result: (MOVBstore [off] {sym} ptr (SRWconst <typ.UInt32> x [c]) mem) @@ -7873,6 +8641,15 @@ func rewriteValuePPC64_OpPPC64MOVBstore_10(v *Value) bool { v.AddArg(mem) return true } + return false +} +func rewriteValuePPC64_OpPPC64MOVBstore_20(v *Value) bool { + b := v.Block + _ = b + config := b.Func.Config + _ = config + typ := &b.Func.Config.Types + _ = typ // match: (MOVBstore [i7] {s} p (SRDconst w [56]) x0:(MOVBstore [i6] {s} p (SRDconst w [48]) x1:(MOVBstore [i5] {s} p (SRDconst w [40]) x2:(MOVBstore [i4] {s} p (SRDconst w [32]) x3:(MOVWstore [i0] {s} p w mem))))) // cond: !config.BigEndian && i0%4 == 0 && x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && i4 == i0+4 && i5 == i0+5 && i6 == i0+6 && i7 == i0+7 && clobber(x0) && clobber(x1) && clobber(x2) && clobber(x3) // result: (MOVDstore [i0] {s} p w mem) @@ -7982,15 +8759,6 @@ func rewriteValuePPC64_OpPPC64MOVBstore_10(v *Value) bool { v.AddArg(mem) return true } - return false -} -func rewriteValuePPC64_OpPPC64MOVBstore_20(v *Value) bool { - b := v.Block - _ = b - config := b.Func.Config - _ = config - typ := &b.Func.Config.Types - _ = typ // match: (MOVBstore [i7] {s} p w x0:(MOVBstore [i6] {s} p (SRDconst w [8]) x1:(MOVBstore [i5] {s} p (SRDconst w [16]) x2:(MOVBstore [i4] {s} p (SRDconst w [24]) x3:(MOVBstore [i3] {s} p (SRDconst w [32]) x4:(MOVBstore [i2] {s} p (SRDconst w [40]) x5:(MOVBstore [i1] {s} p (SRDconst w [48]) x6:(MOVBstore [i0] {s} p (SRDconst w [56]) mem)))))))) // cond: !config.BigEndian && x0.Uses == 1 && x1.Uses == 1 && x2.Uses == 1 && x3.Uses == 1 && x4.Uses == 1 && x5.Uses == 1 && x6.Uses == 1 && i1 == i0+1 && i2 == i0+2 && i3 == i0+3 && i4 == i0+4 && i5 == i0+5 && i6 == i0+6 && i7 == i0+7 && clobber(x0) && clobber(x1) && clobber(x2) && clobber(x3) && clobber(x4) && clobber(x5) && clobber(x6) // result: (MOVDBRstore (MOVDaddr <typ.Uintptr> [i0] {s} p) w mem) @@ -8170,6 +8938,350 @@ func rewriteValuePPC64_OpPPC64MOVBstore_20(v *Value) bool { } return false } +func rewriteValuePPC64_OpPPC64MOVBstoreidx_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ + // match: (MOVBstoreidx ptr (MOVDconst [c]) val mem) + // cond: is16Bit(c) + // result: (MOVBstore [c] ptr val mem) + for { + _ = v.Args[3] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + val := v.Args[2] + mem := v.Args[3] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVBstore) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx (MOVDconst [c]) ptr val mem) + // cond: is16Bit(c) + // result: (MOVBstore [c] ptr val mem) + for { + _ = v.Args[3] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + val := v.Args[2] + mem := v.Args[3] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVBstore) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (MOVBreg x) mem) + // cond: + // result: (MOVBstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVBreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (MOVBZreg x) mem) + // cond: + // result: (MOVBstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVBZreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (MOVHreg x) mem) + // cond: + // result: (MOVBstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVHreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (MOVHZreg x) mem) + // cond: + // result: (MOVBstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVHZreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (MOVWreg x) mem) + // cond: + // result: (MOVBstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVWreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (MOVWZreg x) mem) + // cond: + // result: (MOVBstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVWZreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (SRWconst (MOVHreg x) [c]) mem) + // cond: c <= 8 + // result: (MOVBstoreidx [off] {sym} ptr idx (SRWconst <typ.UInt32> x [c]) mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64SRWconst { + break + } + c := v_2.AuxInt + v_2_0 := v_2.Args[0] + if v_2_0.Op != OpPPC64MOVHreg { + break + } + x := v_2_0.Args[0] + mem := v.Args[3] + if !(c <= 8) { + break + } + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v0 := b.NewValue0(v.Pos, OpPPC64SRWconst, typ.UInt32) + v0.AuxInt = c + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (SRWconst (MOVHZreg x) [c]) mem) + // cond: c <= 8 + // result: (MOVBstoreidx [off] {sym} ptr idx (SRWconst <typ.UInt32> x [c]) mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64SRWconst { + break + } + c := v_2.AuxInt + v_2_0 := v_2.Args[0] + if v_2_0.Op != OpPPC64MOVHZreg { + break + } + x := v_2_0.Args[0] + mem := v.Args[3] + if !(c <= 8) { + break + } + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v0 := b.NewValue0(v.Pos, OpPPC64SRWconst, typ.UInt32) + v0.AuxInt = c + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(mem) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVBstoreidx_10(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ + // match: (MOVBstoreidx [off] {sym} ptr idx (SRWconst (MOVWreg x) [c]) mem) + // cond: c <= 24 + // result: (MOVBstoreidx [off] {sym} ptr idx (SRWconst <typ.UInt32> x [c]) mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64SRWconst { + break + } + c := v_2.AuxInt + v_2_0 := v_2.Args[0] + if v_2_0.Op != OpPPC64MOVWreg { + break + } + x := v_2_0.Args[0] + mem := v.Args[3] + if !(c <= 24) { + break + } + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v0 := b.NewValue0(v.Pos, OpPPC64SRWconst, typ.UInt32) + v0.AuxInt = c + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(mem) + return true + } + // match: (MOVBstoreidx [off] {sym} ptr idx (SRWconst (MOVWZreg x) [c]) mem) + // cond: c <= 24 + // result: (MOVBstoreidx [off] {sym} ptr idx (SRWconst <typ.UInt32> x [c]) mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64SRWconst { + break + } + c := v_2.AuxInt + v_2_0 := v_2.Args[0] + if v_2_0.Op != OpPPC64MOVWZreg { + break + } + x := v_2_0.Args[0] + mem := v.Args[3] + if !(c <= 24) { + break + } + v.reset(OpPPC64MOVBstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v0 := b.NewValue0(v.Pos, OpPPC64SRWconst, typ.UInt32) + v0.AuxInt = c + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(mem) + return true + } + return false +} func rewriteValuePPC64_OpPPC64MOVBstorezero_0(v *Value) bool { // match: (MOVBstorezero [off1] {sym} (ADDconst [off2] x) mem) // cond: is16Bit(off1+off2) @@ -8299,6 +9411,77 @@ func rewriteValuePPC64_OpPPC64MOVDload_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVDload [0] {sym} p:(ADD ptr idx) mem) + // cond: sym == nil && p.Uses == 1 + // result: (MOVDloadidx ptr idx mem) + for { + if v.AuxInt != 0 { + break + } + sym := v.Aux + _ = v.Args[1] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + mem := v.Args[1] + if !(sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVDloadidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(mem) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVDloadidx_0(v *Value) bool { + // match: (MOVDloadidx ptr (MOVDconst [c]) mem) + // cond: is16Bit(c) + // result: (MOVDload [c] ptr mem) + for { + _ = v.Args[2] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVDload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVDloadidx (MOVDconst [c]) ptr mem) + // cond: is16Bit(c) + // result: (MOVDload [c] ptr mem) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVDload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVDstore_0(v *Value) bool { @@ -8377,8 +9560,8 @@ func rewriteValuePPC64_OpPPC64MOVDstore_0(v *Value) bool { v.AddArg(mem) return true } - // match: (MOVDstore [off] {sym} ptr (MOVDconst [c]) mem) - // cond: c == 0 + // match: (MOVDstore [off] {sym} ptr (MOVDconst [0]) mem) + // cond: // result: (MOVDstorezero [off] {sym} ptr mem) for { off := v.AuxInt @@ -8389,11 +9572,10 @@ func rewriteValuePPC64_OpPPC64MOVDstore_0(v *Value) bool { if v_1.Op != OpPPC64MOVDconst { break } - c := v_1.AuxInt - mem := v.Args[2] - if !(c == 0) { + if v_1.AuxInt != 0 { break } + mem := v.Args[2] v.reset(OpPPC64MOVDstorezero) v.AuxInt = off v.Aux = sym @@ -8401,6 +9583,81 @@ func rewriteValuePPC64_OpPPC64MOVDstore_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVDstore [off] {sym} p:(ADD ptr idx) val mem) + // cond: off == 0 && sym == nil && p.Uses == 1 + // result: (MOVDstoreidx ptr idx val mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + val := v.Args[1] + mem := v.Args[2] + if !(off == 0 && sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVDstoreidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(val) + v.AddArg(mem) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVDstoreidx_0(v *Value) bool { + // match: (MOVDstoreidx ptr (MOVDconst [c]) val mem) + // cond: is16Bit(c) + // result: (MOVDstore [c] ptr val mem) + for { + _ = v.Args[3] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + val := v.Args[2] + mem := v.Args[3] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVDstore) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (MOVDstoreidx (MOVDconst [c]) ptr val mem) + // cond: is16Bit(c) + // result: (MOVDstore [c] ptr val mem) + for { + _ = v.Args[3] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + val := v.Args[2] + mem := v.Args[3] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVDstore) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVDstorezero_0(v *Value) bool { @@ -8588,9 +9845,84 @@ func rewriteValuePPC64_OpPPC64MOVHZload_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVHZload [0] {sym} p:(ADD ptr idx) mem) + // cond: sym == nil && p.Uses == 1 + // result: (MOVHZloadidx ptr idx mem) + for { + if v.AuxInt != 0 { + break + } + sym := v.Aux + _ = v.Args[1] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + mem := v.Args[1] + if !(sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVHZloadidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(mem) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVHZloadidx_0(v *Value) bool { + // match: (MOVHZloadidx ptr (MOVDconst [c]) mem) + // cond: is16Bit(c) + // result: (MOVHZload [c] ptr mem) + for { + _ = v.Args[2] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVHZload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVHZloadidx (MOVDconst [c]) ptr mem) + // cond: is16Bit(c) + // result: (MOVHZload [c] ptr mem) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVHZload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVHZreg_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (MOVHZreg y:(ANDconst [c] _)) // cond: uint64(c) <= 0xFFFF // result: y @@ -8608,6 +9940,102 @@ func rewriteValuePPC64_OpPPC64MOVHZreg_0(v *Value) bool { v.AddArg(y) return true } + // match: (MOVHZreg (SRWconst [c] (MOVBZreg x))) + // cond: + // result: (SRWconst [c] (MOVBZreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVBZreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVBZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVHZreg (SRWconst [c] (MOVHZreg x))) + // cond: + // result: (SRWconst [c] (MOVHZreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVHZreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVHZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVHZreg (SRWconst [c] x)) + // cond: sizeof(x.Type) <= 16 + // result: (SRWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(sizeof(x.Type) <= 16) { + break + } + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVHZreg (SRDconst [c] x)) + // cond: c>=48 + // result: (SRDconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c >= 48) { + break + } + v.reset(OpPPC64SRDconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVHZreg (SRWconst [c] x)) + // cond: c>=16 + // result: (SRWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c >= 16) { + break + } + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v.AddArg(x) + return true + } // match: (MOVHZreg y:(MOVHZreg _)) // cond: // result: y @@ -8661,6 +10089,37 @@ func rewriteValuePPC64_OpPPC64MOVHZreg_0(v *Value) bool { v.AddArg(x) return true } + return false +} +func rewriteValuePPC64_OpPPC64MOVHZreg_10(v *Value) bool { + // match: (MOVHZreg x:(MOVBZload _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVBZload { + break + } + _ = x.Args[1] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVHZreg x:(MOVBZloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVBZloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } // match: (MOVHZreg x:(MOVHZload _ _)) // cond: // result: x @@ -8675,6 +10134,37 @@ func rewriteValuePPC64_OpPPC64MOVHZreg_0(v *Value) bool { v.AddArg(x) return true } + // match: (MOVHZreg x:(MOVHZloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVHZloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVHZreg x:(Arg <t>)) + // cond: (is8BitInt(t) || is16BitInt(t)) && !isSigned(t) + // result: x + for { + x := v.Args[0] + if x.Op != OpArg { + break + } + t := x.Type + if !((is8BitInt(t) || is16BitInt(t)) && !isSigned(t)) { + break + } + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } // match: (MOVHZreg (MOVDconst [c])) // cond: // result: (MOVDconst [int64(uint16(c))]) @@ -8740,9 +10230,84 @@ func rewriteValuePPC64_OpPPC64MOVHload_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVHload [0] {sym} p:(ADD ptr idx) mem) + // cond: sym == nil && p.Uses == 1 + // result: (MOVHloadidx ptr idx mem) + for { + if v.AuxInt != 0 { + break + } + sym := v.Aux + _ = v.Args[1] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + mem := v.Args[1] + if !(sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVHloadidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(mem) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVHloadidx_0(v *Value) bool { + // match: (MOVHloadidx ptr (MOVDconst [c]) mem) + // cond: is16Bit(c) + // result: (MOVHload [c] ptr mem) + for { + _ = v.Args[2] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVHload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVHloadidx (MOVDconst [c]) ptr mem) + // cond: is16Bit(c) + // result: (MOVHload [c] ptr mem) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVHload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVHreg_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (MOVHreg y:(ANDconst [c] _)) // cond: uint64(c) <= 0x7FFF // result: y @@ -8760,6 +10325,138 @@ func rewriteValuePPC64_OpPPC64MOVHreg_0(v *Value) bool { v.AddArg(y) return true } + // match: (MOVHreg (SRAWconst [c] (MOVBreg x))) + // cond: + // result: (SRAWconst [c] (MOVBreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVBreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVBreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVHreg (SRAWconst [c] (MOVHreg x))) + // cond: + // result: (SRAWconst [c] (MOVHreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVHreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVHreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVHreg (SRAWconst [c] x)) + // cond: sizeof(x.Type) <= 16 + // result: (SRAWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(sizeof(x.Type) <= 16) { + break + } + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVHreg (SRDconst [c] x)) + // cond: c>48 + // result: (SRDconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c > 48) { + break + } + v.reset(OpPPC64SRDconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVHreg (SRDconst [c] x)) + // cond: c==48 + // result: (SRADconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c == 48) { + break + } + v.reset(OpPPC64SRADconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVHreg (SRWconst [c] x)) + // cond: c>16 + // result: (SRWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c > 16) { + break + } + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVHreg (SRWconst [c] x)) + // cond: c==16 + // result: (SRAWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c == 16) { + break + } + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v.AddArg(x) + return true + } // match: (MOVHreg y:(MOVHreg _)) // cond: // result: y @@ -8786,6 +10483,9 @@ func rewriteValuePPC64_OpPPC64MOVHreg_0(v *Value) bool { v.AddArg(y) return true } + return false +} +func rewriteValuePPC64_OpPPC64MOVHreg_10(v *Value) bool { // match: (MOVHreg y:(MOVHZreg x)) // cond: // result: (MOVHreg x) @@ -8813,6 +10513,37 @@ func rewriteValuePPC64_OpPPC64MOVHreg_0(v *Value) bool { v.AddArg(x) return true } + // match: (MOVHreg x:(MOVHloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVHloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVHreg x:(Arg <t>)) + // cond: (is8BitInt(t) || is16BitInt(t)) && isSigned(t) + // result: x + for { + x := v.Args[0] + if x.Op != OpArg { + break + } + t := x.Type + if !((is8BitInt(t) || is16BitInt(t)) && isSigned(t)) { + break + } + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } // match: (MOVHreg (MOVDconst [c])) // cond: // result: (MOVDconst [int64(int16(c))]) @@ -8886,8 +10617,8 @@ func rewriteValuePPC64_OpPPC64MOVHstore_0(v *Value) bool { v.AddArg(mem) return true } - // match: (MOVHstore [off] {sym} ptr (MOVDconst [c]) mem) - // cond: c == 0 + // match: (MOVHstore [off] {sym} ptr (MOVDconst [0]) mem) + // cond: // result: (MOVHstorezero [off] {sym} ptr mem) for { off := v.AuxInt @@ -8898,11 +10629,10 @@ func rewriteValuePPC64_OpPPC64MOVHstore_0(v *Value) bool { if v_1.Op != OpPPC64MOVDconst { break } - c := v_1.AuxInt - mem := v.Args[2] - if !(c == 0) { + if v_1.AuxInt != 0 { break } + mem := v.Args[2] v.reset(OpPPC64MOVHstorezero) v.AuxInt = off v.Aux = sym @@ -8910,6 +10640,32 @@ func rewriteValuePPC64_OpPPC64MOVHstore_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVHstore [off] {sym} p:(ADD ptr idx) val mem) + // cond: off == 0 && sym == nil && p.Uses == 1 + // result: (MOVHstoreidx ptr idx val mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + val := v.Args[1] + mem := v.Args[2] + if !(off == 0 && sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVHstoreidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (MOVHstore [off] {sym} ptr (MOVHreg x) mem) // cond: // result: (MOVHstore [off] {sym} ptr x mem) @@ -9086,6 +10842,151 @@ func rewriteValuePPC64_OpPPC64MOVHstore_0(v *Value) bool { } return false } +func rewriteValuePPC64_OpPPC64MOVHstoreidx_0(v *Value) bool { + // match: (MOVHstoreidx ptr (MOVDconst [c]) val mem) + // cond: is16Bit(c) + // result: (MOVHstore [c] ptr val mem) + for { + _ = v.Args[3] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + val := v.Args[2] + mem := v.Args[3] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVHstore) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (MOVHstoreidx (MOVDconst [c]) ptr val mem) + // cond: is16Bit(c) + // result: (MOVHstore [c] ptr val mem) + for { + _ = v.Args[3] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + val := v.Args[2] + mem := v.Args[3] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVHstore) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (MOVHstoreidx [off] {sym} ptr idx (MOVHreg x) mem) + // cond: + // result: (MOVHstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVHreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVHstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVHstoreidx [off] {sym} ptr idx (MOVHZreg x) mem) + // cond: + // result: (MOVHstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVHZreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVHstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVHstoreidx [off] {sym} ptr idx (MOVWreg x) mem) + // cond: + // result: (MOVHstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVWreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVHstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVHstoreidx [off] {sym} ptr idx (MOVWZreg x) mem) + // cond: + // result: (MOVHstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVWZreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVHstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + return false +} func rewriteValuePPC64_OpPPC64MOVHstorezero_0(v *Value) bool { // match: (MOVHstorezero [off1] {sym} (ADDconst [off2] x) mem) // cond: is16Bit(off1+off2) @@ -9231,9 +11132,84 @@ func rewriteValuePPC64_OpPPC64MOVWZload_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVWZload [0] {sym} p:(ADD ptr idx) mem) + // cond: sym == nil && p.Uses == 1 + // result: (MOVWZloadidx ptr idx mem) + for { + if v.AuxInt != 0 { + break + } + sym := v.Aux + _ = v.Args[1] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + mem := v.Args[1] + if !(sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVWZloadidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(mem) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVWZloadidx_0(v *Value) bool { + // match: (MOVWZloadidx ptr (MOVDconst [c]) mem) + // cond: is16Bit(c) + // result: (MOVWZload [c] ptr mem) + for { + _ = v.Args[2] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVWZload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVWZloadidx (MOVDconst [c]) ptr mem) + // cond: is16Bit(c) + // result: (MOVWZload [c] ptr mem) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVWZload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVWZreg_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (MOVWZreg y:(ANDconst [c] _)) // cond: uint64(c) <= 0xFFFFFFFF // result: y @@ -9295,6 +11271,105 @@ func rewriteValuePPC64_OpPPC64MOVWZreg_0(v *Value) bool { v.AddArg(y) return true } + // match: (MOVWZreg (SRWconst [c] (MOVBZreg x))) + // cond: + // result: (SRWconst [c] (MOVBZreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVBZreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVBZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVWZreg (SRWconst [c] (MOVHZreg x))) + // cond: + // result: (SRWconst [c] (MOVHZreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVHZreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVHZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVWZreg (SRWconst [c] (MOVWZreg x))) + // cond: + // result: (SRWconst [c] (MOVWZreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVWZreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVWZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVWZreg (SRWconst [c] x)) + // cond: sizeof(x.Type) <= 32 + // result: (SRWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(sizeof(x.Type) <= 32) { + break + } + v.reset(OpPPC64SRWconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVWZreg (SRDconst [c] x)) + // cond: c>=32 + // result: (SRDconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c >= 32) { + break + } + v.reset(OpPPC64SRDconst) + v.AuxInt = c + v.AddArg(x) + return true + } // match: (MOVWZreg y:(MOVWZreg _)) // cond: // result: y @@ -9321,6 +11396,9 @@ func rewriteValuePPC64_OpPPC64MOVWZreg_0(v *Value) bool { v.AddArg(y) return true } + return false +} +func rewriteValuePPC64_OpPPC64MOVWZreg_10(v *Value) bool { // match: (MOVWZreg y:(MOVBZreg _)) // cond: // result: y @@ -9375,6 +11453,123 @@ func rewriteValuePPC64_OpPPC64MOVWZreg_0(v *Value) bool { v.AddArg(x) return true } + // match: (MOVWZreg x:(MOVBZload _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVBZload { + break + } + _ = x.Args[1] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWZreg x:(MOVBZloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVBZloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWZreg x:(MOVHZload _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVHZload { + break + } + _ = x.Args[1] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWZreg x:(MOVHZloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVHZloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWZreg x:(MOVWZload _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVWZload { + break + } + _ = x.Args[1] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWZreg x:(MOVWZloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVWZloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVWZreg_20(v *Value) bool { + // match: (MOVWZreg x:(Arg <t>)) + // cond: (is8BitInt(t) || is16BitInt(t) || is32BitInt(t)) && !isSigned(t) + // result: x + for { + x := v.Args[0] + if x.Op != OpArg { + break + } + t := x.Type + if !((is8BitInt(t) || is16BitInt(t) || is32BitInt(t)) && !isSigned(t)) { + break + } + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWZreg (MOVDconst [c])) + // cond: + // result: (MOVDconst [int64(uint32(c))]) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + v.reset(OpPPC64MOVDconst) + v.AuxInt = int64(uint32(c)) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVWload_0(v *Value) bool { @@ -9427,9 +11622,84 @@ func rewriteValuePPC64_OpPPC64MOVWload_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVWload [0] {sym} p:(ADD ptr idx) mem) + // cond: sym == nil && p.Uses == 1 + // result: (MOVWloadidx ptr idx mem) + for { + if v.AuxInt != 0 { + break + } + sym := v.Aux + _ = v.Args[1] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + mem := v.Args[1] + if !(sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVWloadidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(mem) + return true + } + return false +} +func rewriteValuePPC64_OpPPC64MOVWloadidx_0(v *Value) bool { + // match: (MOVWloadidx ptr (MOVDconst [c]) mem) + // cond: is16Bit(c) + // result: (MOVWload [c] ptr mem) + for { + _ = v.Args[2] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVWload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } + // match: (MOVWloadidx (MOVDconst [c]) ptr mem) + // cond: is16Bit(c) + // result: (MOVWload [c] ptr mem) + for { + _ = v.Args[2] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + mem := v.Args[2] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVWload) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(mem) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVWreg_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (MOVWreg y:(ANDconst [c] _)) // cond: uint64(c) <= 0xFFFF // result: y @@ -9491,6 +11761,123 @@ func rewriteValuePPC64_OpPPC64MOVWreg_0(v *Value) bool { v.AddArg(y) return true } + // match: (MOVWreg (SRAWconst [c] (MOVBreg x))) + // cond: + // result: (SRAWconst [c] (MOVBreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVBreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVBreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVWreg (SRAWconst [c] (MOVHreg x))) + // cond: + // result: (SRAWconst [c] (MOVHreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVHreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVHreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVWreg (SRAWconst [c] (MOVWreg x))) + // cond: + // result: (SRAWconst [c] (MOVWreg x)) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + v_0_0 := v_0.Args[0] + if v_0_0.Op != OpPPC64MOVWreg { + break + } + x := v_0_0.Args[0] + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v0 := b.NewValue0(v.Pos, OpPPC64MOVWreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + return true + } + // match: (MOVWreg (SRAWconst [c] x)) + // cond: sizeof(x.Type) <= 32 + // result: (SRAWconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRAWconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(sizeof(x.Type) <= 32) { + break + } + v.reset(OpPPC64SRAWconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVWreg (SRDconst [c] x)) + // cond: c>32 + // result: (SRDconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c > 32) { + break + } + v.reset(OpPPC64SRDconst) + v.AuxInt = c + v.AddArg(x) + return true + } + // match: (MOVWreg (SRDconst [c] x)) + // cond: c==32 + // result: (SRADconst [c] x) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64SRDconst { + break + } + c := v_0.AuxInt + x := v_0.Args[0] + if !(c == 32) { + break + } + v.reset(OpPPC64SRADconst) + v.AuxInt = c + v.AddArg(x) + return true + } // match: (MOVWreg y:(MOVWreg _)) // cond: // result: y @@ -9504,6 +11891,9 @@ func rewriteValuePPC64_OpPPC64MOVWreg_0(v *Value) bool { v.AddArg(y) return true } + return false +} +func rewriteValuePPC64_OpPPC64MOVWreg_10(v *Value) bool { // match: (MOVWreg y:(MOVHreg _)) // cond: // result: y @@ -9543,6 +11933,92 @@ func rewriteValuePPC64_OpPPC64MOVWreg_0(v *Value) bool { v.AddArg(x) return true } + // match: (MOVWreg x:(MOVHload _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVHload { + break + } + _ = x.Args[1] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWreg x:(MOVHloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVHloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWreg x:(MOVWload _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVWload { + break + } + _ = x.Args[1] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWreg x:(MOVWloadidx _ _ _)) + // cond: + // result: x + for { + x := v.Args[0] + if x.Op != OpPPC64MOVWloadidx { + break + } + _ = x.Args[2] + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWreg x:(Arg <t>)) + // cond: (is8BitInt(t) || is16BitInt(t) || is32BitInt(t)) && isSigned(t) + // result: x + for { + x := v.Args[0] + if x.Op != OpArg { + break + } + t := x.Type + if !((is8BitInt(t) || is16BitInt(t) || is32BitInt(t)) && isSigned(t)) { + break + } + v.reset(OpCopy) + v.Type = x.Type + v.AddArg(x) + return true + } + // match: (MOVWreg (MOVDconst [c])) + // cond: + // result: (MOVDconst [int64(int32(c))]) + for { + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + v.reset(OpPPC64MOVDconst) + v.AuxInt = int64(int32(c)) + return true + } return false } func rewriteValuePPC64_OpPPC64MOVWstore_0(v *Value) bool { @@ -9599,8 +12075,8 @@ func rewriteValuePPC64_OpPPC64MOVWstore_0(v *Value) bool { v.AddArg(mem) return true } - // match: (MOVWstore [off] {sym} ptr (MOVDconst [c]) mem) - // cond: c == 0 + // match: (MOVWstore [off] {sym} ptr (MOVDconst [0]) mem) + // cond: // result: (MOVWstorezero [off] {sym} ptr mem) for { off := v.AuxInt @@ -9611,11 +12087,10 @@ func rewriteValuePPC64_OpPPC64MOVWstore_0(v *Value) bool { if v_1.Op != OpPPC64MOVDconst { break } - c := v_1.AuxInt - mem := v.Args[2] - if !(c == 0) { + if v_1.AuxInt != 0 { break } + mem := v.Args[2] v.reset(OpPPC64MOVWstorezero) v.AuxInt = off v.Aux = sym @@ -9623,6 +12098,32 @@ func rewriteValuePPC64_OpPPC64MOVWstore_0(v *Value) bool { v.AddArg(mem) return true } + // match: (MOVWstore [off] {sym} p:(ADD ptr idx) val mem) + // cond: off == 0 && sym == nil && p.Uses == 1 + // result: (MOVWstoreidx ptr idx val mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[2] + p := v.Args[0] + if p.Op != OpPPC64ADD { + break + } + _ = p.Args[1] + ptr := p.Args[0] + idx := p.Args[1] + val := v.Args[1] + mem := v.Args[2] + if !(off == 0 && sym == nil && p.Uses == 1) { + break + } + v.reset(OpPPC64MOVWstoreidx) + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(val) + v.AddArg(mem) + return true + } // match: (MOVWstore [off] {sym} ptr (MOVWreg x) mem) // cond: // result: (MOVWstore [off] {sym} ptr x mem) @@ -9669,6 +12170,103 @@ func rewriteValuePPC64_OpPPC64MOVWstore_0(v *Value) bool { } return false } +func rewriteValuePPC64_OpPPC64MOVWstoreidx_0(v *Value) bool { + // match: (MOVWstoreidx ptr (MOVDconst [c]) val mem) + // cond: is16Bit(c) + // result: (MOVWstore [c] ptr val mem) + for { + _ = v.Args[3] + ptr := v.Args[0] + v_1 := v.Args[1] + if v_1.Op != OpPPC64MOVDconst { + break + } + c := v_1.AuxInt + val := v.Args[2] + mem := v.Args[3] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVWstore) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (MOVWstoreidx (MOVDconst [c]) ptr val mem) + // cond: is16Bit(c) + // result: (MOVWstore [c] ptr val mem) + for { + _ = v.Args[3] + v_0 := v.Args[0] + if v_0.Op != OpPPC64MOVDconst { + break + } + c := v_0.AuxInt + ptr := v.Args[1] + val := v.Args[2] + mem := v.Args[3] + if !(is16Bit(c)) { + break + } + v.reset(OpPPC64MOVWstore) + v.AuxInt = c + v.AddArg(ptr) + v.AddArg(val) + v.AddArg(mem) + return true + } + // match: (MOVWstoreidx [off] {sym} ptr idx (MOVWreg x) mem) + // cond: + // result: (MOVWstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVWreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVWstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + // match: (MOVWstoreidx [off] {sym} ptr idx (MOVWZreg x) mem) + // cond: + // result: (MOVWstoreidx [off] {sym} ptr idx x mem) + for { + off := v.AuxInt + sym := v.Aux + _ = v.Args[3] + ptr := v.Args[0] + idx := v.Args[1] + v_2 := v.Args[2] + if v_2.Op != OpPPC64MOVWZreg { + break + } + x := v_2.Args[0] + mem := v.Args[3] + v.reset(OpPPC64MOVWstoreidx) + v.AuxInt = off + v.Aux = sym + v.AddArg(ptr) + v.AddArg(idx) + v.AddArg(x) + v.AddArg(mem) + return true + } + return false +} func rewriteValuePPC64_OpPPC64MOVWstorezero_0(v *Value) bool { // match: (MOVWstorezero [off1] {sym} (ADDconst [off2] x) mem) // cond: is16Bit(off1+off2) @@ -24104,6 +26702,23 @@ func rewriteValuePPC64_OpRsh16Ux16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh16Ux16 x y) + // cond: shiftIsBounded(v) + // result: (SRW (MOVHZreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVHZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh16Ux16 x y) // cond: // result: (SRW (ZeroExt16to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt16to64 y))))) for { @@ -24176,6 +26791,23 @@ func rewriteValuePPC64_OpRsh16Ux32_0(v *Value) bool { return true } // match: (Rsh16Ux32 x y) + // cond: shiftIsBounded(v) + // result: (SRW (MOVHZreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVHZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh16Ux32 x y) // cond: // result: (SRW (ZeroExt16to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt32to64 y))))) for { @@ -24265,6 +26897,23 @@ func rewriteValuePPC64_OpRsh16Ux64_0(v *Value) bool { return true } // match: (Rsh16Ux64 x y) + // cond: shiftIsBounded(v) + // result: (SRW (MOVHZreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVHZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh16Ux64 x y) // cond: // result: (SRW (ZeroExt16to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] y)))) for { @@ -24293,6 +26942,23 @@ func rewriteValuePPC64_OpRsh16Ux8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh16Ux8 x y) + // cond: shiftIsBounded(v) + // result: (SRW (MOVHZreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVHZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh16Ux8 x y) // cond: // result: (SRW (ZeroExt16to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt8to64 y))))) for { @@ -24323,6 +26989,23 @@ func rewriteValuePPC64_OpRsh16x16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh16x16 x y) + // cond: shiftIsBounded(v) + // result: (SRAW (MOVHreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVHreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh16x16 x y) // cond: // result: (SRAW (SignExt16to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt16to64 y))))) for { @@ -24395,6 +27078,23 @@ func rewriteValuePPC64_OpRsh16x32_0(v *Value) bool { return true } // match: (Rsh16x32 x y) + // cond: shiftIsBounded(v) + // result: (SRAW (MOVHreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVHreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh16x32 x y) // cond: // result: (SRAW (SignExt16to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt32to64 y))))) for { @@ -24488,6 +27188,23 @@ func rewriteValuePPC64_OpRsh16x64_0(v *Value) bool { return true } // match: (Rsh16x64 x y) + // cond: shiftIsBounded(v) + // result: (SRAW (MOVHreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVHreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh16x64 x y) // cond: // result: (SRAW (SignExt16to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] y)))) for { @@ -24516,6 +27233,23 @@ func rewriteValuePPC64_OpRsh16x8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh16x8 x y) + // cond: shiftIsBounded(v) + // result: (SRAW (MOVHreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVHreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh16x8 x y) // cond: // result: (SRAW (SignExt16to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-16] (ZeroExt8to64 y))))) for { @@ -24546,6 +27280,21 @@ func rewriteValuePPC64_OpRsh32Ux16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh32Ux16 x y) + // cond: shiftIsBounded(v) + // result: (SRW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh32Ux16 x y) // cond: // result: (SRW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt16to64 y))))) for { @@ -24612,6 +27361,21 @@ func rewriteValuePPC64_OpRsh32Ux32_0(v *Value) bool { return true } // match: (Rsh32Ux32 x y) + // cond: shiftIsBounded(v) + // result: (SRW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh32Ux32 x y) // cond: // result: (SRW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt32to64 y))))) for { @@ -24694,6 +27458,21 @@ func rewriteValuePPC64_OpRsh32Ux64_0(v *Value) bool { v.AddArg(x) return true } + // match: (Rsh32Ux64 x y) + // cond: shiftIsBounded(v) + // result: (SRW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v.AddArg(x) + v.AddArg(y) + return true + } // match: (Rsh32Ux64 x (AND y (MOVDconst [31]))) // cond: // result: (SRW x (ANDconst <typ.Int32> [31] y)) @@ -24918,6 +27697,13 @@ func rewriteValuePPC64_OpRsh32Ux64_0(v *Value) bool { v.AddArg(v0) return true } + return false +} +func rewriteValuePPC64_OpRsh32Ux64_10(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (Rsh32Ux64 x y) // cond: // result: (SRW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] y)))) @@ -24945,6 +27731,21 @@ func rewriteValuePPC64_OpRsh32Ux8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh32Ux8 x y) + // cond: shiftIsBounded(v) + // result: (SRW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh32Ux8 x y) // cond: // result: (SRW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt8to64 y))))) for { @@ -24973,6 +27774,21 @@ func rewriteValuePPC64_OpRsh32x16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh32x16 x y) + // cond: shiftIsBounded(v) + // result: (SRAW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh32x16 x y) // cond: // result: (SRAW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt16to64 y))))) for { @@ -25039,6 +27855,21 @@ func rewriteValuePPC64_OpRsh32x32_0(v *Value) bool { return true } // match: (Rsh32x32 x y) + // cond: shiftIsBounded(v) + // result: (SRAW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh32x32 x y) // cond: // result: (SRAW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt32to64 y))))) for { @@ -25123,6 +27954,21 @@ func rewriteValuePPC64_OpRsh32x64_0(v *Value) bool { v.AddArg(x) return true } + // match: (Rsh32x64 x y) + // cond: shiftIsBounded(v) + // result: (SRAW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v.AddArg(x) + v.AddArg(y) + return true + } // match: (Rsh32x64 x (AND y (MOVDconst [31]))) // cond: // result: (SRAW x (ANDconst <typ.Int32> [31] y)) @@ -25347,6 +28193,13 @@ func rewriteValuePPC64_OpRsh32x64_0(v *Value) bool { v.AddArg(v0) return true } + return false +} +func rewriteValuePPC64_OpRsh32x64_10(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (Rsh32x64 x y) // cond: // result: (SRAW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] y)))) @@ -25374,6 +28227,21 @@ func rewriteValuePPC64_OpRsh32x8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh32x8 x y) + // cond: shiftIsBounded(v) + // result: (SRAW x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh32x8 x y) // cond: // result: (SRAW x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-32] (ZeroExt8to64 y))))) for { @@ -25402,6 +28270,21 @@ func rewriteValuePPC64_OpRsh64Ux16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh64Ux16 x y) + // cond: shiftIsBounded(v) + // result: (SRD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh64Ux16 x y) // cond: // result: (SRD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt16to64 y))))) for { @@ -25468,6 +28351,21 @@ func rewriteValuePPC64_OpRsh64Ux32_0(v *Value) bool { return true } // match: (Rsh64Ux32 x y) + // cond: shiftIsBounded(v) + // result: (SRD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh64Ux32 x y) // cond: // result: (SRD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt32to64 y))))) for { @@ -25550,6 +28448,21 @@ func rewriteValuePPC64_OpRsh64Ux64_0(v *Value) bool { v.AddArg(x) return true } + // match: (Rsh64Ux64 x y) + // cond: shiftIsBounded(v) + // result: (SRD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRD) + v.AddArg(x) + v.AddArg(y) + return true + } // match: (Rsh64Ux64 x (AND y (MOVDconst [63]))) // cond: // result: (SRD x (ANDconst <typ.Int64> [63] y)) @@ -25774,6 +28687,13 @@ func rewriteValuePPC64_OpRsh64Ux64_0(v *Value) bool { v.AddArg(v0) return true } + return false +} +func rewriteValuePPC64_OpRsh64Ux64_10(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (Rsh64Ux64 x y) // cond: // result: (SRD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] y)))) @@ -25801,6 +28721,21 @@ func rewriteValuePPC64_OpRsh64Ux8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh64Ux8 x y) + // cond: shiftIsBounded(v) + // result: (SRD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh64Ux8 x y) // cond: // result: (SRD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt8to64 y))))) for { @@ -25829,6 +28764,21 @@ func rewriteValuePPC64_OpRsh64x16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh64x16 x y) + // cond: shiftIsBounded(v) + // result: (SRAD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh64x16 x y) // cond: // result: (SRAD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt16to64 y))))) for { @@ -25895,6 +28845,21 @@ func rewriteValuePPC64_OpRsh64x32_0(v *Value) bool { return true } // match: (Rsh64x32 x y) + // cond: shiftIsBounded(v) + // result: (SRAD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh64x32 x y) // cond: // result: (SRAD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt32to64 y))))) for { @@ -25979,6 +28944,21 @@ func rewriteValuePPC64_OpRsh64x64_0(v *Value) bool { v.AddArg(x) return true } + // match: (Rsh64x64 x y) + // cond: shiftIsBounded(v) + // result: (SRAD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAD) + v.AddArg(x) + v.AddArg(y) + return true + } // match: (Rsh64x64 x (AND y (MOVDconst [63]))) // cond: // result: (SRAD x (ANDconst <typ.Int64> [63] y)) @@ -26203,6 +29183,13 @@ func rewriteValuePPC64_OpRsh64x64_0(v *Value) bool { v.AddArg(v0) return true } + return false +} +func rewriteValuePPC64_OpRsh64x64_10(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ // match: (Rsh64x64 x y) // cond: // result: (SRAD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] y)))) @@ -26230,6 +29217,21 @@ func rewriteValuePPC64_OpRsh64x8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh64x8 x y) + // cond: shiftIsBounded(v) + // result: (SRAD x y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAD) + v.AddArg(x) + v.AddArg(y) + return true + } + // match: (Rsh64x8 x y) // cond: // result: (SRAD x (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-64] (ZeroExt8to64 y))))) for { @@ -26258,6 +29260,23 @@ func rewriteValuePPC64_OpRsh8Ux16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh8Ux16 x y) + // cond: shiftIsBounded(v) + // result: (SRW (MOVBZreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVBZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh8Ux16 x y) // cond: // result: (SRW (ZeroExt8to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt16to64 y))))) for { @@ -26330,6 +29349,23 @@ func rewriteValuePPC64_OpRsh8Ux32_0(v *Value) bool { return true } // match: (Rsh8Ux32 x y) + // cond: shiftIsBounded(v) + // result: (SRW (MOVBZreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVBZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh8Ux32 x y) // cond: // result: (SRW (ZeroExt8to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt32to64 y))))) for { @@ -26419,6 +29455,23 @@ func rewriteValuePPC64_OpRsh8Ux64_0(v *Value) bool { return true } // match: (Rsh8Ux64 x y) + // cond: shiftIsBounded(v) + // result: (SRW (MOVBZreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVBZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh8Ux64 x y) // cond: // result: (SRW (ZeroExt8to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] y)))) for { @@ -26447,6 +29500,23 @@ func rewriteValuePPC64_OpRsh8Ux8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh8Ux8 x y) + // cond: shiftIsBounded(v) + // result: (SRW (MOVBZreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVBZreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh8Ux8 x y) // cond: // result: (SRW (ZeroExt8to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt8to64 y))))) for { @@ -26477,6 +29547,23 @@ func rewriteValuePPC64_OpRsh8x16_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh8x16 x y) + // cond: shiftIsBounded(v) + // result: (SRAW (MOVBreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVBreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh8x16 x y) // cond: // result: (SRAW (SignExt8to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt16to64 y))))) for { @@ -26549,6 +29636,23 @@ func rewriteValuePPC64_OpRsh8x32_0(v *Value) bool { return true } // match: (Rsh8x32 x y) + // cond: shiftIsBounded(v) + // result: (SRAW (MOVBreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVBreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh8x32 x y) // cond: // result: (SRAW (SignExt8to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt32to64 y))))) for { @@ -26642,6 +29746,23 @@ func rewriteValuePPC64_OpRsh8x64_0(v *Value) bool { return true } // match: (Rsh8x64 x y) + // cond: shiftIsBounded(v) + // result: (SRAW (MOVBreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVBreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh8x64 x y) // cond: // result: (SRAW (SignExt8to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] y)))) for { @@ -26670,6 +29791,23 @@ func rewriteValuePPC64_OpRsh8x8_0(v *Value) bool { typ := &b.Func.Config.Types _ = typ // match: (Rsh8x8 x y) + // cond: shiftIsBounded(v) + // result: (SRAW (MOVBreg x) y) + for { + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + if !(shiftIsBounded(v)) { + break + } + v.reset(OpPPC64SRAW) + v0 := b.NewValue0(v.Pos, OpPPC64MOVBreg, typ.Int64) + v0.AddArg(x) + v.AddArg(v0) + v.AddArg(y) + return true + } + // match: (Rsh8x8 x y) // cond: // result: (SRAW (SignExt8to32 x) (ORN y <typ.Int64> (MaskIfNotCarry (ADDconstForCarry [-8] (ZeroExt8to64 y))))) for { @@ -27043,69 +30181,141 @@ func rewriteValuePPC64_OpTrunc_0(v *Value) bool { } func rewriteValuePPC64_OpTrunc16to8_0(v *Value) bool { // match: (Trunc16to8 x) - // cond: + // cond: isSigned(x.Type) // result: (MOVBreg x) for { x := v.Args[0] + if !(isSigned(x.Type)) { + break + } v.reset(OpPPC64MOVBreg) v.AddArg(x) return true } + // match: (Trunc16to8 x) + // cond: + // result: (MOVBZreg x) + for { + x := v.Args[0] + v.reset(OpPPC64MOVBZreg) + v.AddArg(x) + return true + } } func rewriteValuePPC64_OpTrunc32to16_0(v *Value) bool { // match: (Trunc32to16 x) - // cond: + // cond: isSigned(x.Type) // result: (MOVHreg x) for { x := v.Args[0] + if !(isSigned(x.Type)) { + break + } v.reset(OpPPC64MOVHreg) v.AddArg(x) return true } + // match: (Trunc32to16 x) + // cond: + // result: (MOVHZreg x) + for { + x := v.Args[0] + v.reset(OpPPC64MOVHZreg) + v.AddArg(x) + return true + } } func rewriteValuePPC64_OpTrunc32to8_0(v *Value) bool { // match: (Trunc32to8 x) - // cond: + // cond: isSigned(x.Type) // result: (MOVBreg x) for { x := v.Args[0] + if !(isSigned(x.Type)) { + break + } v.reset(OpPPC64MOVBreg) v.AddArg(x) return true } + // match: (Trunc32to8 x) + // cond: + // result: (MOVBZreg x) + for { + x := v.Args[0] + v.reset(OpPPC64MOVBZreg) + v.AddArg(x) + return true + } } func rewriteValuePPC64_OpTrunc64to16_0(v *Value) bool { // match: (Trunc64to16 x) - // cond: + // cond: isSigned(x.Type) // result: (MOVHreg x) for { x := v.Args[0] + if !(isSigned(x.Type)) { + break + } v.reset(OpPPC64MOVHreg) v.AddArg(x) return true } + // match: (Trunc64to16 x) + // cond: + // result: (MOVHZreg x) + for { + x := v.Args[0] + v.reset(OpPPC64MOVHZreg) + v.AddArg(x) + return true + } } func rewriteValuePPC64_OpTrunc64to32_0(v *Value) bool { // match: (Trunc64to32 x) - // cond: + // cond: isSigned(x.Type) // result: (MOVWreg x) for { x := v.Args[0] + if !(isSigned(x.Type)) { + break + } v.reset(OpPPC64MOVWreg) v.AddArg(x) return true } + // match: (Trunc64to32 x) + // cond: + // result: (MOVWZreg x) + for { + x := v.Args[0] + v.reset(OpPPC64MOVWZreg) + v.AddArg(x) + return true + } } func rewriteValuePPC64_OpTrunc64to8_0(v *Value) bool { // match: (Trunc64to8 x) - // cond: + // cond: isSigned(x.Type) // result: (MOVBreg x) for { x := v.Args[0] + if !(isSigned(x.Type)) { + break + } v.reset(OpPPC64MOVBreg) v.AddArg(x) return true } + // match: (Trunc64to8 x) + // cond: + // result: (MOVBZreg x) + for { + x := v.Args[0] + v.reset(OpPPC64MOVBZreg) + v.AddArg(x) + return true + } } func rewriteValuePPC64_OpWB_0(v *Value) bool { // match: (WB {fn} destptr srcptr mem) diff --git a/src/cmd/compile/internal/ssa/rewriteWasm.go b/src/cmd/compile/internal/ssa/rewriteWasm.go index c07651ef0e..b92556db90 100644 --- a/src/cmd/compile/internal/ssa/rewriteWasm.go +++ b/src/cmd/compile/internal/ssa/rewriteWasm.go @@ -5071,7 +5071,7 @@ func rewriteValueWasm_OpWasmF64Add_0(v *Value) bool { _ = typ // match: (F64Add (F64Const [x]) (F64Const [y])) // cond: - // result: (F64Const [f2i(i2f(x) + i2f(y))]) + // result: (F64Const [auxFrom64F(auxTo64F(x) + auxTo64F(y))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -5085,7 +5085,7 @@ func rewriteValueWasm_OpWasmF64Add_0(v *Value) bool { } y := v_1.AuxInt v.reset(OpWasmF64Const) - v.AuxInt = f2i(i2f(x) + i2f(y)) + v.AuxInt = auxFrom64F(auxTo64F(x) + auxTo64F(y)) return true } // match: (F64Add (F64Const [x]) y) @@ -5115,7 +5115,7 @@ func rewriteValueWasm_OpWasmF64Mul_0(v *Value) bool { _ = typ // match: (F64Mul (F64Const [x]) (F64Const [y])) // cond: - // result: (F64Const [f2i(i2f(x) * i2f(y))]) + // result: (F64Const [auxFrom64F(auxTo64F(x) * auxTo64F(y))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -5129,7 +5129,7 @@ func rewriteValueWasm_OpWasmF64Mul_0(v *Value) bool { } y := v_1.AuxInt v.reset(OpWasmF64Const) - v.AuxInt = f2i(i2f(x) * i2f(y)) + v.AuxInt = auxFrom64F(auxTo64F(x) * auxTo64F(y)) return true } // match: (F64Mul (F64Const [x]) y) diff --git a/src/cmd/compile/internal/ssa/rewritegeneric.go b/src/cmd/compile/internal/ssa/rewritegeneric.go index 81bebede46..2f239faa49 100644 --- a/src/cmd/compile/internal/ssa/rewritegeneric.go +++ b/src/cmd/compile/internal/ssa/rewritegeneric.go @@ -2409,7 +2409,7 @@ func rewriteValuegeneric_OpAdd32_30(v *Value) bool { func rewriteValuegeneric_OpAdd32F_0(v *Value) bool { // match: (Add32F (Const32F [c]) (Const32F [d])) // cond: - // result: (Const32F [f2i(float64(i2f32(c) + i2f32(d)))]) + // result: (Const32F [auxFrom32F(auxTo32F(c) + auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -2423,12 +2423,12 @@ func rewriteValuegeneric_OpAdd32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(i2f32(c) + i2f32(d))) + v.AuxInt = auxFrom32F(auxTo32F(c) + auxTo32F(d)) return true } // match: (Add32F (Const32F [d]) (Const32F [c])) // cond: - // result: (Const32F [f2i(float64(i2f32(c) + i2f32(d)))]) + // result: (Const32F [auxFrom32F(auxTo32F(c) + auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -2442,43 +2442,7 @@ func rewriteValuegeneric_OpAdd32F_0(v *Value) bool { } c := v_1.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(i2f32(c) + i2f32(d))) - return true - } - // match: (Add32F x (Const32F [0])) - // cond: - // result: x - for { - _ = v.Args[1] - x := v.Args[0] - v_1 := v.Args[1] - if v_1.Op != OpConst32F { - break - } - if v_1.AuxInt != 0 { - break - } - v.reset(OpCopy) - v.Type = x.Type - v.AddArg(x) - return true - } - // match: (Add32F (Const32F [0]) x) - // cond: - // result: x - for { - _ = v.Args[1] - v_0 := v.Args[0] - if v_0.Op != OpConst32F { - break - } - if v_0.AuxInt != 0 { - break - } - x := v.Args[1] - v.reset(OpCopy) - v.Type = x.Type - v.AddArg(x) + v.AuxInt = auxFrom32F(auxTo32F(c) + auxTo32F(d)) return true } return false @@ -3454,7 +3418,7 @@ func rewriteValuegeneric_OpAdd64_30(v *Value) bool { func rewriteValuegeneric_OpAdd64F_0(v *Value) bool { // match: (Add64F (Const64F [c]) (Const64F [d])) // cond: - // result: (Const64F [f2i(i2f(c) + i2f(d))]) + // result: (Const64F [auxFrom64F(auxTo64F(c) + auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -3468,12 +3432,12 @@ func rewriteValuegeneric_OpAdd64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(i2f(c) + i2f(d)) + v.AuxInt = auxFrom64F(auxTo64F(c) + auxTo64F(d)) return true } // match: (Add64F (Const64F [d]) (Const64F [c])) // cond: - // result: (Const64F [f2i(i2f(c) + i2f(d))]) + // result: (Const64F [auxFrom64F(auxTo64F(c) + auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -3487,43 +3451,7 @@ func rewriteValuegeneric_OpAdd64F_0(v *Value) bool { } c := v_1.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(i2f(c) + i2f(d)) - return true - } - // match: (Add64F x (Const64F [0])) - // cond: - // result: x - for { - _ = v.Args[1] - x := v.Args[0] - v_1 := v.Args[1] - if v_1.Op != OpConst64F { - break - } - if v_1.AuxInt != 0 { - break - } - v.reset(OpCopy) - v.Type = x.Type - v.AddArg(x) - return true - } - // match: (Add64F (Const64F [0]) x) - // cond: - // result: x - for { - _ = v.Args[1] - v_0 := v.Args[0] - if v_0.Op != OpConst64F { - break - } - if v_0.AuxInt != 0 { - break - } - x := v.Args[1] - v.reset(OpCopy) - v.Type = x.Type - v.AddArg(x) + v.AuxInt = auxFrom64F(auxTo64F(c) + auxTo64F(d)) return true } return false @@ -7566,7 +7494,7 @@ func rewriteValuegeneric_OpConvert_0(v *Value) bool { func rewriteValuegeneric_OpCvt32Fto32_0(v *Value) bool { // match: (Cvt32Fto32 (Const32F [c])) // cond: - // result: (Const32 [int64(int32(i2f(c)))]) + // result: (Const32 [int64(int32(auxTo32F(c)))]) for { v_0 := v.Args[0] if v_0.Op != OpConst32F { @@ -7574,7 +7502,7 @@ func rewriteValuegeneric_OpCvt32Fto32_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst32) - v.AuxInt = int64(int32(i2f(c))) + v.AuxInt = int64(int32(auxTo32F(c))) return true } return false @@ -7582,7 +7510,7 @@ func rewriteValuegeneric_OpCvt32Fto32_0(v *Value) bool { func rewriteValuegeneric_OpCvt32Fto64_0(v *Value) bool { // match: (Cvt32Fto64 (Const32F [c])) // cond: - // result: (Const64 [int64(i2f(c))]) + // result: (Const64 [int64(auxTo32F(c))]) for { v_0 := v.Args[0] if v_0.Op != OpConst32F { @@ -7590,7 +7518,7 @@ func rewriteValuegeneric_OpCvt32Fto64_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst64) - v.AuxInt = int64(i2f(c)) + v.AuxInt = int64(auxTo32F(c)) return true } return false @@ -7614,7 +7542,7 @@ func rewriteValuegeneric_OpCvt32Fto64F_0(v *Value) bool { func rewriteValuegeneric_OpCvt32to32F_0(v *Value) bool { // match: (Cvt32to32F (Const32 [c])) // cond: - // result: (Const32F [f2i(float64(float32(int32(c))))]) + // result: (Const32F [auxFrom32F(float32(int32(c)))]) for { v_0 := v.Args[0] if v_0.Op != OpConst32 { @@ -7622,7 +7550,7 @@ func rewriteValuegeneric_OpCvt32to32F_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(float32(int32(c)))) + v.AuxInt = auxFrom32F(float32(int32(c))) return true } return false @@ -7630,7 +7558,7 @@ func rewriteValuegeneric_OpCvt32to32F_0(v *Value) bool { func rewriteValuegeneric_OpCvt32to64F_0(v *Value) bool { // match: (Cvt32to64F (Const32 [c])) // cond: - // result: (Const64F [f2i(float64(int32(c)))]) + // result: (Const64F [auxFrom64F(float64(int32(c)))]) for { v_0 := v.Args[0] if v_0.Op != OpConst32 { @@ -7638,7 +7566,7 @@ func rewriteValuegeneric_OpCvt32to64F_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(float64(int32(c))) + v.AuxInt = auxFrom64F(float64(int32(c))) return true } return false @@ -7646,7 +7574,7 @@ func rewriteValuegeneric_OpCvt32to64F_0(v *Value) bool { func rewriteValuegeneric_OpCvt64Fto32_0(v *Value) bool { // match: (Cvt64Fto32 (Const64F [c])) // cond: - // result: (Const32 [int64(int32(i2f(c)))]) + // result: (Const32 [int64(int32(auxTo64F(c)))]) for { v_0 := v.Args[0] if v_0.Op != OpConst64F { @@ -7654,7 +7582,7 @@ func rewriteValuegeneric_OpCvt64Fto32_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst32) - v.AuxInt = int64(int32(i2f(c))) + v.AuxInt = int64(int32(auxTo64F(c))) return true } return false @@ -7662,7 +7590,7 @@ func rewriteValuegeneric_OpCvt64Fto32_0(v *Value) bool { func rewriteValuegeneric_OpCvt64Fto32F_0(v *Value) bool { // match: (Cvt64Fto32F (Const64F [c])) // cond: - // result: (Const32F [f2i(float64(i2f32(c)))]) + // result: (Const32F [auxFrom32F(float32(auxTo64F(c)))]) for { v_0 := v.Args[0] if v_0.Op != OpConst64F { @@ -7670,7 +7598,7 @@ func rewriteValuegeneric_OpCvt64Fto32F_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(i2f32(c))) + v.AuxInt = auxFrom32F(float32(auxTo64F(c))) return true } return false @@ -7678,7 +7606,7 @@ func rewriteValuegeneric_OpCvt64Fto32F_0(v *Value) bool { func rewriteValuegeneric_OpCvt64Fto64_0(v *Value) bool { // match: (Cvt64Fto64 (Const64F [c])) // cond: - // result: (Const64 [int64(i2f(c))]) + // result: (Const64 [int64(auxTo64F(c))]) for { v_0 := v.Args[0] if v_0.Op != OpConst64F { @@ -7686,7 +7614,7 @@ func rewriteValuegeneric_OpCvt64Fto64_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst64) - v.AuxInt = int64(i2f(c)) + v.AuxInt = int64(auxTo64F(c)) return true } return false @@ -7694,7 +7622,7 @@ func rewriteValuegeneric_OpCvt64Fto64_0(v *Value) bool { func rewriteValuegeneric_OpCvt64to32F_0(v *Value) bool { // match: (Cvt64to32F (Const64 [c])) // cond: - // result: (Const32F [f2i(float64(float32(c)))]) + // result: (Const32F [auxFrom32F(float32(c))]) for { v_0 := v.Args[0] if v_0.Op != OpConst64 { @@ -7702,7 +7630,7 @@ func rewriteValuegeneric_OpCvt64to32F_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(float32(c))) + v.AuxInt = auxFrom32F(float32(c)) return true } return false @@ -7710,7 +7638,7 @@ func rewriteValuegeneric_OpCvt64to32F_0(v *Value) bool { func rewriteValuegeneric_OpCvt64to64F_0(v *Value) bool { // match: (Cvt64to64F (Const64 [c])) // cond: - // result: (Const64F [f2i(float64(c))]) + // result: (Const64F [auxFrom64F(float64(c))]) for { v_0 := v.Args[0] if v_0.Op != OpConst64 { @@ -7718,7 +7646,7 @@ func rewriteValuegeneric_OpCvt64to64F_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(float64(c)) + v.AuxInt = auxFrom64F(float64(c)) return true } return false @@ -8342,7 +8270,7 @@ func rewriteValuegeneric_OpDiv32F_0(v *Value) bool { _ = b // match: (Div32F (Const32F [c]) (Const32F [d])) // cond: - // result: (Const32F [f2i(float64(i2f32(c) / i2f32(d)))]) + // result: (Const32F [auxFrom32F(auxTo32F(c) / auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -8356,12 +8284,12 @@ func rewriteValuegeneric_OpDiv32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(i2f32(c) / i2f32(d))) + v.AuxInt = auxFrom32F(auxTo32F(c) / auxTo32F(d)) return true } // match: (Div32F x (Const32F <t> [c])) - // cond: reciprocalExact32(float32(i2f(c))) - // result: (Mul32F x (Const32F <t> [f2i(1/i2f(c))])) + // cond: reciprocalExact32(auxTo32F(c)) + // result: (Mul32F x (Const32F <t> [auxFrom32F(1/auxTo32F(c))])) for { _ = v.Args[1] x := v.Args[0] @@ -8371,13 +8299,13 @@ func rewriteValuegeneric_OpDiv32F_0(v *Value) bool { } t := v_1.Type c := v_1.AuxInt - if !(reciprocalExact32(float32(i2f(c)))) { + if !(reciprocalExact32(auxTo32F(c))) { break } v.reset(OpMul32F) v.AddArg(x) v0 := b.NewValue0(v.Pos, OpConst32F, t) - v0.AuxInt = f2i(1 / i2f(c)) + v0.AuxInt = auxFrom32F(1 / auxTo32F(c)) v.AddArg(v0) return true } @@ -8866,7 +8794,7 @@ func rewriteValuegeneric_OpDiv64F_0(v *Value) bool { _ = b // match: (Div64F (Const64F [c]) (Const64F [d])) // cond: - // result: (Const64F [f2i(i2f(c) / i2f(d))]) + // result: (Const64F [auxFrom64F(auxTo64F(c) / auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -8880,12 +8808,12 @@ func rewriteValuegeneric_OpDiv64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(i2f(c) / i2f(d)) + v.AuxInt = auxFrom64F(auxTo64F(c) / auxTo64F(d)) return true } // match: (Div64F x (Const64F <t> [c])) - // cond: reciprocalExact64(i2f(c)) - // result: (Mul64F x (Const64F <t> [f2i(1/i2f(c))])) + // cond: reciprocalExact64(auxTo64F(c)) + // result: (Mul64F x (Const64F <t> [auxFrom64F(1/auxTo64F(c))])) for { _ = v.Args[1] x := v.Args[0] @@ -8895,13 +8823,13 @@ func rewriteValuegeneric_OpDiv64F_0(v *Value) bool { } t := v_1.Type c := v_1.AuxInt - if !(reciprocalExact64(i2f(c))) { + if !(reciprocalExact64(auxTo64F(c))) { break } v.reset(OpMul64F) v.AddArg(x) v0 := b.NewValue0(v.Pos, OpConst64F, t) - v0.AuxInt = f2i(1 / i2f(c)) + v0.AuxInt = auxFrom64F(1 / auxTo64F(c)) v.AddArg(v0) return true } @@ -9802,7 +9730,7 @@ func rewriteValuegeneric_OpEq32_0(v *Value) bool { func rewriteValuegeneric_OpEq32F_0(v *Value) bool { // match: (Eq32F (Const32F [c]) (Const32F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) == i2f(d))]) + // result: (ConstBool [b2i(auxTo32F(c) == auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -9816,12 +9744,12 @@ func rewriteValuegeneric_OpEq32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) == i2f(d)) + v.AuxInt = b2i(auxTo32F(c) == auxTo32F(d)) return true } // match: (Eq32F (Const32F [d]) (Const32F [c])) // cond: - // result: (ConstBool [b2i(i2f(c) == i2f(d))]) + // result: (ConstBool [b2i(auxTo32F(c) == auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -9835,7 +9763,7 @@ func rewriteValuegeneric_OpEq32F_0(v *Value) bool { } c := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) == i2f(d)) + v.AuxInt = b2i(auxTo32F(c) == auxTo32F(d)) return true } return false @@ -10081,7 +10009,7 @@ func rewriteValuegeneric_OpEq64_0(v *Value) bool { func rewriteValuegeneric_OpEq64F_0(v *Value) bool { // match: (Eq64F (Const64F [c]) (Const64F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) == i2f(d))]) + // result: (ConstBool [b2i(auxTo64F(c) == auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -10095,12 +10023,12 @@ func rewriteValuegeneric_OpEq64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) == i2f(d)) + v.AuxInt = b2i(auxTo64F(c) == auxTo64F(d)) return true } // match: (Eq64F (Const64F [d]) (Const64F [c])) // cond: - // result: (ConstBool [b2i(i2f(c) == i2f(d))]) + // result: (ConstBool [b2i(auxTo64F(c) == auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -10114,7 +10042,7 @@ func rewriteValuegeneric_OpEq64F_0(v *Value) bool { } c := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) == i2f(d)) + v.AuxInt = b2i(auxTo64F(c) == auxTo64F(d)) return true } return false @@ -11077,7 +11005,7 @@ func rewriteValuegeneric_OpGeq32_0(v *Value) bool { func rewriteValuegeneric_OpGeq32F_0(v *Value) bool { // match: (Geq32F (Const32F [c]) (Const32F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) >= i2f(d))]) + // result: (ConstBool [b2i(auxTo32F(c) >= auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -11091,7 +11019,7 @@ func rewriteValuegeneric_OpGeq32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) >= i2f(d)) + v.AuxInt = b2i(auxTo32F(c) >= auxTo32F(d)) return true } return false @@ -11143,7 +11071,7 @@ func rewriteValuegeneric_OpGeq64_0(v *Value) bool { func rewriteValuegeneric_OpGeq64F_0(v *Value) bool { // match: (Geq64F (Const64F [c]) (Const64F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) >= i2f(d))]) + // result: (ConstBool [b2i(auxTo64F(c) >= auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -11157,7 +11085,7 @@ func rewriteValuegeneric_OpGeq64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) >= i2f(d)) + v.AuxInt = b2i(auxTo64F(c) >= auxTo64F(d)) return true } return false @@ -11297,7 +11225,7 @@ func rewriteValuegeneric_OpGreater32_0(v *Value) bool { func rewriteValuegeneric_OpGreater32F_0(v *Value) bool { // match: (Greater32F (Const32F [c]) (Const32F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) > i2f(d))]) + // result: (ConstBool [b2i(auxTo32F(c) > auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -11311,7 +11239,7 @@ func rewriteValuegeneric_OpGreater32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) > i2f(d)) + v.AuxInt = b2i(auxTo32F(c) > auxTo32F(d)) return true } return false @@ -11363,7 +11291,7 @@ func rewriteValuegeneric_OpGreater64_0(v *Value) bool { func rewriteValuegeneric_OpGreater64F_0(v *Value) bool { // match: (Greater64F (Const64F [c]) (Const64F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) > i2f(d))]) + // result: (ConstBool [b2i(auxTo64F(c) > auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -11377,7 +11305,7 @@ func rewriteValuegeneric_OpGreater64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) > i2f(d)) + v.AuxInt = b2i(auxTo64F(c) > auxTo64F(d)) return true } return false @@ -12945,7 +12873,7 @@ func rewriteValuegeneric_OpLeq32_0(v *Value) bool { func rewriteValuegeneric_OpLeq32F_0(v *Value) bool { // match: (Leq32F (Const32F [c]) (Const32F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) <= i2f(d))]) + // result: (ConstBool [b2i(auxTo32F(c) <= auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -12959,7 +12887,7 @@ func rewriteValuegeneric_OpLeq32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) <= i2f(d)) + v.AuxInt = b2i(auxTo32F(c) <= auxTo32F(d)) return true } return false @@ -13011,7 +12939,7 @@ func rewriteValuegeneric_OpLeq64_0(v *Value) bool { func rewriteValuegeneric_OpLeq64F_0(v *Value) bool { // match: (Leq64F (Const64F [c]) (Const64F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) <= i2f(d))]) + // result: (ConstBool [b2i(auxTo64F(c) <= auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -13025,7 +12953,7 @@ func rewriteValuegeneric_OpLeq64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) <= i2f(d)) + v.AuxInt = b2i(auxTo64F(c) <= auxTo64F(d)) return true } return false @@ -13165,7 +13093,7 @@ func rewriteValuegeneric_OpLess32_0(v *Value) bool { func rewriteValuegeneric_OpLess32F_0(v *Value) bool { // match: (Less32F (Const32F [c]) (Const32F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) < i2f(d))]) + // result: (ConstBool [b2i(auxTo32F(c) < auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -13179,7 +13107,7 @@ func rewriteValuegeneric_OpLess32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) < i2f(d)) + v.AuxInt = b2i(auxTo32F(c) < auxTo32F(d)) return true } return false @@ -13231,7 +13159,7 @@ func rewriteValuegeneric_OpLess64_0(v *Value) bool { func rewriteValuegeneric_OpLess64F_0(v *Value) bool { // match: (Less64F (Const64F [c]) (Const64F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) < i2f(d))]) + // result: (ConstBool [b2i(auxTo64F(c) < auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -13245,7 +13173,7 @@ func rewriteValuegeneric_OpLess64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) < i2f(d)) + v.AuxInt = b2i(auxTo64F(c) < auxTo64F(d)) return true } return false @@ -13483,7 +13411,7 @@ func rewriteValuegeneric_OpLoad_0(v *Value) bool { } // match: (Load <t1> p1 (Store {t2} p2 (Const32 [x]) _)) // cond: isSamePtr(p1,p2) && sizeof(t2) == 4 && is32BitFloat(t1) - // result: (Const32F [f2i(extend32Fto64F(math.Float32frombits(uint32(x))))]) + // result: (Const32F [auxFrom32F(math.Float32frombits(uint32(x)))]) for { t1 := v.Type _ = v.Args[1] @@ -13504,7 +13432,7 @@ func rewriteValuegeneric_OpLoad_0(v *Value) bool { break } v.reset(OpConst32F) - v.AuxInt = f2i(extend32Fto64F(math.Float32frombits(uint32(x)))) + v.AuxInt = auxFrom32F(math.Float32frombits(uint32(x))) return true } // match: (Load <t1> p1 (Store {t2} p2 (Const64F [x]) _)) @@ -13535,7 +13463,7 @@ func rewriteValuegeneric_OpLoad_0(v *Value) bool { } // match: (Load <t1> p1 (Store {t2} p2 (Const32F [x]) _)) // cond: isSamePtr(p1,p2) && sizeof(t2) == 4 && is32BitInt(t1) - // result: (Const32 [int64(int32(math.Float32bits(truncate64Fto32F(i2f(x)))))]) + // result: (Const32 [int64(int32(math.Float32bits(auxTo32F(x))))]) for { t1 := v.Type _ = v.Args[1] @@ -13556,7 +13484,7 @@ func rewriteValuegeneric_OpLoad_0(v *Value) bool { break } v.reset(OpConst32) - v.AuxInt = int64(int32(math.Float32bits(truncate64Fto32F(i2f(x))))) + v.AuxInt = int64(int32(math.Float32bits(auxTo32F(x)))) return true } // match: (Load <t1> op:(OffPtr [o1] p1) (Store {t2} p2 _ mem:(Zero [n] p3 _))) @@ -16223,9 +16151,9 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { v.AddArg(v0) return true } - // match: (Move {t1} [n] dst p1 mem:(Store {t2} op2:(OffPtr [o2] p2) d1 (Store {t3} op3:(OffPtr [0] p3) d2 _))) + // match: (Move {t1} [n] dst p1 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 (Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _))) // cond: isSamePtr(p1, p2) && isSamePtr(p2, p3) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) && registerizable(b, t2) && registerizable(b, t3) && o2 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) - // result: (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 (Store {t3} (OffPtr <t3.(*types.Type)> [0] dst) d2 mem)) + // result: (Store {t2} (OffPtr <tt2> [o2] dst) d1 (Store {t3} (OffPtr <tt3> [0] dst) d2 mem)) for { n := v.AuxInt t1 := v.Aux @@ -16242,6 +16170,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op2.Op != OpOffPtr { break } + tt2 := op2.Type o2 := op2.AuxInt p2 := op2.Args[0] d1 := mem.Args[1] @@ -16255,6 +16184,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op3.Op != OpOffPtr { break } + tt3 := op3.Type if op3.AuxInt != 0 { break } @@ -16265,14 +16195,14 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { } v.reset(OpStore) v.Aux = t2 - v0 := b.NewValue0(v.Pos, OpOffPtr, t2.(*types.Type)) + v0 := b.NewValue0(v.Pos, OpOffPtr, tt2) v0.AuxInt = o2 v0.AddArg(dst) v.AddArg(v0) v.AddArg(d1) v1 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v1.Aux = t3 - v2 := b.NewValue0(v.Pos, OpOffPtr, t3.(*types.Type)) + v2 := b.NewValue0(v.Pos, OpOffPtr, tt3) v2.AuxInt = 0 v2.AddArg(dst) v1.AddArg(v2) @@ -16281,9 +16211,9 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { v.AddArg(v1) return true } - // match: (Move {t1} [n] dst p1 mem:(Store {t2} op2:(OffPtr [o2] p2) d1 (Store {t3} op3:(OffPtr [o3] p3) d2 (Store {t4} op4:(OffPtr [0] p4) d3 _)))) + // match: (Move {t1} [n] dst p1 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2 (Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _)))) // cond: isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) && alignof(t4) <= alignof(t1) && registerizable(b, t2) && registerizable(b, t3) && registerizable(b, t4) && o3 == sizeof(t4) && o2-o3 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) + sizeof(t4) - // result: (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 (Store {t3} (OffPtr <t3.(*types.Type)> [o3] dst) d2 (Store {t4} (OffPtr <t4.(*types.Type)> [0] dst) d3 mem))) + // result: (Store {t2} (OffPtr <tt2> [o2] dst) d1 (Store {t3} (OffPtr <tt3> [o3] dst) d2 (Store {t4} (OffPtr <tt4> [0] dst) d3 mem))) for { n := v.AuxInt t1 := v.Aux @@ -16300,6 +16230,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op2.Op != OpOffPtr { break } + tt2 := op2.Type o2 := op2.AuxInt p2 := op2.Args[0] d1 := mem.Args[1] @@ -16313,6 +16244,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op3.Op != OpOffPtr { break } + tt3 := op3.Type o3 := op3.AuxInt p3 := op3.Args[0] d2 := mem_2.Args[1] @@ -16326,6 +16258,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op4.Op != OpOffPtr { break } + tt4 := op4.Type if op4.AuxInt != 0 { break } @@ -16336,21 +16269,21 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { } v.reset(OpStore) v.Aux = t2 - v0 := b.NewValue0(v.Pos, OpOffPtr, t2.(*types.Type)) + v0 := b.NewValue0(v.Pos, OpOffPtr, tt2) v0.AuxInt = o2 v0.AddArg(dst) v.AddArg(v0) v.AddArg(d1) v1 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v1.Aux = t3 - v2 := b.NewValue0(v.Pos, OpOffPtr, t3.(*types.Type)) + v2 := b.NewValue0(v.Pos, OpOffPtr, tt3) v2.AuxInt = o3 v2.AddArg(dst) v1.AddArg(v2) v1.AddArg(d2) v3 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v3.Aux = t4 - v4 := b.NewValue0(v.Pos, OpOffPtr, t4.(*types.Type)) + v4 := b.NewValue0(v.Pos, OpOffPtr, tt4) v4.AuxInt = 0 v4.AddArg(dst) v3.AddArg(v4) @@ -16360,9 +16293,9 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { v.AddArg(v1) return true } - // match: (Move {t1} [n] dst p1 mem:(Store {t2} op2:(OffPtr [o2] p2) d1 (Store {t3} op3:(OffPtr [o3] p3) d2 (Store {t4} op4:(OffPtr [o4] p4) d3 (Store {t5} op5:(OffPtr [0] p5) d4 _))))) + // match: (Move {t1} [n] dst p1 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2 (Store {t4} op4:(OffPtr <tt4> [o4] p4) d3 (Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _))))) // cond: isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) && alignof(t4) <= alignof(t1) && alignof(t5) <= alignof(t1) && registerizable(b, t2) && registerizable(b, t3) && registerizable(b, t4) && registerizable(b, t5) && o4 == sizeof(t5) && o3-o4 == sizeof(t4) && o2-o3 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) + sizeof(t4) + sizeof(t5) - // result: (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 (Store {t3} (OffPtr <t3.(*types.Type)> [o3] dst) d2 (Store {t4} (OffPtr <t4.(*types.Type)> [o4] dst) d3 (Store {t5} (OffPtr <t5.(*types.Type)> [0] dst) d4 mem)))) + // result: (Store {t2} (OffPtr <tt2> [o2] dst) d1 (Store {t3} (OffPtr <tt3> [o3] dst) d2 (Store {t4} (OffPtr <tt4> [o4] dst) d3 (Store {t5} (OffPtr <tt5> [0] dst) d4 mem)))) for { n := v.AuxInt t1 := v.Aux @@ -16379,6 +16312,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op2.Op != OpOffPtr { break } + tt2 := op2.Type o2 := op2.AuxInt p2 := op2.Args[0] d1 := mem.Args[1] @@ -16392,6 +16326,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op3.Op != OpOffPtr { break } + tt3 := op3.Type o3 := op3.AuxInt p3 := op3.Args[0] d2 := mem_2.Args[1] @@ -16405,6 +16340,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op4.Op != OpOffPtr { break } + tt4 := op4.Type o4 := op4.AuxInt p4 := op4.Args[0] d3 := mem_2_2.Args[1] @@ -16418,6 +16354,7 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { if op5.Op != OpOffPtr { break } + tt5 := op5.Type if op5.AuxInt != 0 { break } @@ -16428,28 +16365,28 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { } v.reset(OpStore) v.Aux = t2 - v0 := b.NewValue0(v.Pos, OpOffPtr, t2.(*types.Type)) + v0 := b.NewValue0(v.Pos, OpOffPtr, tt2) v0.AuxInt = o2 v0.AddArg(dst) v.AddArg(v0) v.AddArg(d1) v1 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v1.Aux = t3 - v2 := b.NewValue0(v.Pos, OpOffPtr, t3.(*types.Type)) + v2 := b.NewValue0(v.Pos, OpOffPtr, tt3) v2.AuxInt = o3 v2.AddArg(dst) v1.AddArg(v2) v1.AddArg(d2) v3 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v3.Aux = t4 - v4 := b.NewValue0(v.Pos, OpOffPtr, t4.(*types.Type)) + v4 := b.NewValue0(v.Pos, OpOffPtr, tt4) v4.AuxInt = o4 v4.AddArg(dst) v3.AddArg(v4) v3.AddArg(d3) v5 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v5.Aux = t5 - v6 := b.NewValue0(v.Pos, OpOffPtr, t5.(*types.Type)) + v6 := b.NewValue0(v.Pos, OpOffPtr, tt5) v6.AuxInt = 0 v6.AddArg(dst) v5.AddArg(v6) @@ -16465,9 +16402,9 @@ func rewriteValuegeneric_OpMove_0(v *Value) bool { func rewriteValuegeneric_OpMove_10(v *Value) bool { b := v.Block _ = b - // match: (Move {t1} [n] dst p1 mem:(VarDef (Store {t2} op2:(OffPtr [o2] p2) d1 (Store {t3} op3:(OffPtr [0] p3) d2 _)))) + // match: (Move {t1} [n] dst p1 mem:(VarDef (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 (Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _)))) // cond: isSamePtr(p1, p2) && isSamePtr(p2, p3) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) && registerizable(b, t2) && registerizable(b, t3) && o2 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) - // result: (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 (Store {t3} (OffPtr <t3.(*types.Type)> [0] dst) d2 mem)) + // result: (Store {t2} (OffPtr <tt2> [o2] dst) d1 (Store {t3} (OffPtr <tt3> [0] dst) d2 mem)) for { n := v.AuxInt t1 := v.Aux @@ -16488,6 +16425,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op2.Op != OpOffPtr { break } + tt2 := op2.Type o2 := op2.AuxInt p2 := op2.Args[0] d1 := mem_0.Args[1] @@ -16501,6 +16439,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op3.Op != OpOffPtr { break } + tt3 := op3.Type if op3.AuxInt != 0 { break } @@ -16511,14 +16450,14 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { } v.reset(OpStore) v.Aux = t2 - v0 := b.NewValue0(v.Pos, OpOffPtr, t2.(*types.Type)) + v0 := b.NewValue0(v.Pos, OpOffPtr, tt2) v0.AuxInt = o2 v0.AddArg(dst) v.AddArg(v0) v.AddArg(d1) v1 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v1.Aux = t3 - v2 := b.NewValue0(v.Pos, OpOffPtr, t3.(*types.Type)) + v2 := b.NewValue0(v.Pos, OpOffPtr, tt3) v2.AuxInt = 0 v2.AddArg(dst) v1.AddArg(v2) @@ -16527,9 +16466,9 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { v.AddArg(v1) return true } - // match: (Move {t1} [n] dst p1 mem:(VarDef (Store {t2} op2:(OffPtr [o2] p2) d1 (Store {t3} op3:(OffPtr [o3] p3) d2 (Store {t4} op4:(OffPtr [0] p4) d3 _))))) + // match: (Move {t1} [n] dst p1 mem:(VarDef (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2 (Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _))))) // cond: isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) && alignof(t4) <= alignof(t1) && registerizable(b, t2) && registerizable(b, t3) && registerizable(b, t4) && o3 == sizeof(t4) && o2-o3 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) + sizeof(t4) - // result: (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 (Store {t3} (OffPtr <t3.(*types.Type)> [o3] dst) d2 (Store {t4} (OffPtr <t4.(*types.Type)> [0] dst) d3 mem))) + // result: (Store {t2} (OffPtr <tt2> [o2] dst) d1 (Store {t3} (OffPtr <tt3> [o3] dst) d2 (Store {t4} (OffPtr <tt4> [0] dst) d3 mem))) for { n := v.AuxInt t1 := v.Aux @@ -16550,6 +16489,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op2.Op != OpOffPtr { break } + tt2 := op2.Type o2 := op2.AuxInt p2 := op2.Args[0] d1 := mem_0.Args[1] @@ -16563,6 +16503,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op3.Op != OpOffPtr { break } + tt3 := op3.Type o3 := op3.AuxInt p3 := op3.Args[0] d2 := mem_0_2.Args[1] @@ -16576,6 +16517,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op4.Op != OpOffPtr { break } + tt4 := op4.Type if op4.AuxInt != 0 { break } @@ -16586,21 +16528,21 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { } v.reset(OpStore) v.Aux = t2 - v0 := b.NewValue0(v.Pos, OpOffPtr, t2.(*types.Type)) + v0 := b.NewValue0(v.Pos, OpOffPtr, tt2) v0.AuxInt = o2 v0.AddArg(dst) v.AddArg(v0) v.AddArg(d1) v1 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v1.Aux = t3 - v2 := b.NewValue0(v.Pos, OpOffPtr, t3.(*types.Type)) + v2 := b.NewValue0(v.Pos, OpOffPtr, tt3) v2.AuxInt = o3 v2.AddArg(dst) v1.AddArg(v2) v1.AddArg(d2) v3 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v3.Aux = t4 - v4 := b.NewValue0(v.Pos, OpOffPtr, t4.(*types.Type)) + v4 := b.NewValue0(v.Pos, OpOffPtr, tt4) v4.AuxInt = 0 v4.AddArg(dst) v3.AddArg(v4) @@ -16610,9 +16552,9 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { v.AddArg(v1) return true } - // match: (Move {t1} [n] dst p1 mem:(VarDef (Store {t2} op2:(OffPtr [o2] p2) d1 (Store {t3} op3:(OffPtr [o3] p3) d2 (Store {t4} op4:(OffPtr [o4] p4) d3 (Store {t5} op5:(OffPtr [0] p5) d4 _)))))) + // match: (Move {t1} [n] dst p1 mem:(VarDef (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2 (Store {t4} op4:(OffPtr <tt4> [o4] p4) d3 (Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _)))))) // cond: isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && alignof(t2) <= alignof(t1) && alignof(t3) <= alignof(t1) && alignof(t4) <= alignof(t1) && alignof(t5) <= alignof(t1) && registerizable(b, t2) && registerizable(b, t3) && registerizable(b, t4) && registerizable(b, t5) && o4 == sizeof(t5) && o3-o4 == sizeof(t4) && o2-o3 == sizeof(t3) && n == sizeof(t2) + sizeof(t3) + sizeof(t4) + sizeof(t5) - // result: (Store {t2} (OffPtr <t2.(*types.Type)> [o2] dst) d1 (Store {t3} (OffPtr <t3.(*types.Type)> [o3] dst) d2 (Store {t4} (OffPtr <t4.(*types.Type)> [o4] dst) d3 (Store {t5} (OffPtr <t5.(*types.Type)> [0] dst) d4 mem)))) + // result: (Store {t2} (OffPtr <tt2> [o2] dst) d1 (Store {t3} (OffPtr <tt3> [o3] dst) d2 (Store {t4} (OffPtr <tt4> [o4] dst) d3 (Store {t5} (OffPtr <tt5> [0] dst) d4 mem)))) for { n := v.AuxInt t1 := v.Aux @@ -16633,6 +16575,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op2.Op != OpOffPtr { break } + tt2 := op2.Type o2 := op2.AuxInt p2 := op2.Args[0] d1 := mem_0.Args[1] @@ -16646,6 +16589,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op3.Op != OpOffPtr { break } + tt3 := op3.Type o3 := op3.AuxInt p3 := op3.Args[0] d2 := mem_0_2.Args[1] @@ -16659,6 +16603,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op4.Op != OpOffPtr { break } + tt4 := op4.Type o4 := op4.AuxInt p4 := op4.Args[0] d3 := mem_0_2_2.Args[1] @@ -16672,6 +16617,7 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { if op5.Op != OpOffPtr { break } + tt5 := op5.Type if op5.AuxInt != 0 { break } @@ -16682,28 +16628,28 @@ func rewriteValuegeneric_OpMove_10(v *Value) bool { } v.reset(OpStore) v.Aux = t2 - v0 := b.NewValue0(v.Pos, OpOffPtr, t2.(*types.Type)) + v0 := b.NewValue0(v.Pos, OpOffPtr, tt2) v0.AuxInt = o2 v0.AddArg(dst) v.AddArg(v0) v.AddArg(d1) v1 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v1.Aux = t3 - v2 := b.NewValue0(v.Pos, OpOffPtr, t3.(*types.Type)) + v2 := b.NewValue0(v.Pos, OpOffPtr, tt3) v2.AuxInt = o3 v2.AddArg(dst) v1.AddArg(v2) v1.AddArg(d2) v3 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v3.Aux = t4 - v4 := b.NewValue0(v.Pos, OpOffPtr, t4.(*types.Type)) + v4 := b.NewValue0(v.Pos, OpOffPtr, tt4) v4.AuxInt = o4 v4.AddArg(dst) v3.AddArg(v4) v3.AddArg(d3) v5 := b.NewValue0(v.Pos, OpStore, types.TypeMem) v5.Aux = t5 - v6 := b.NewValue0(v.Pos, OpOffPtr, t5.(*types.Type)) + v6 := b.NewValue0(v.Pos, OpOffPtr, tt5) v6.AuxInt = 0 v6.AddArg(dst) v5.AddArg(v6) @@ -18320,7 +18266,7 @@ func rewriteValuegeneric_OpMul32_10(v *Value) bool { func rewriteValuegeneric_OpMul32F_0(v *Value) bool { // match: (Mul32F (Const32F [c]) (Const32F [d])) // cond: - // result: (Const32F [f2i(float64(i2f32(c) * i2f32(d)))]) + // result: (Const32F [auxFrom32F(auxTo32F(c) * auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -18334,12 +18280,12 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(i2f32(c) * i2f32(d))) + v.AuxInt = auxFrom32F(auxTo32F(c) * auxTo32F(d)) return true } // match: (Mul32F (Const32F [d]) (Const32F [c])) // cond: - // result: (Const32F [f2i(float64(i2f32(c) * i2f32(d)))]) + // result: (Const32F [auxFrom32F(auxTo32F(c) * auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -18353,10 +18299,10 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { } c := v_1.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(i2f32(c) * i2f32(d))) + v.AuxInt = auxFrom32F(auxTo32F(c) * auxTo32F(d)) return true } - // match: (Mul32F x (Const32F [f2i(1)])) + // match: (Mul32F x (Const32F [auxFrom64F(1)])) // cond: // result: x for { @@ -18366,7 +18312,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { if v_1.Op != OpConst32F { break } - if v_1.AuxInt != f2i(1) { + if v_1.AuxInt != auxFrom64F(1) { break } v.reset(OpCopy) @@ -18374,7 +18320,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { v.AddArg(x) return true } - // match: (Mul32F (Const32F [f2i(1)]) x) + // match: (Mul32F (Const32F [auxFrom64F(1)]) x) // cond: // result: x for { @@ -18383,7 +18329,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { if v_0.Op != OpConst32F { break } - if v_0.AuxInt != f2i(1) { + if v_0.AuxInt != auxFrom64F(1) { break } x := v.Args[1] @@ -18392,7 +18338,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { v.AddArg(x) return true } - // match: (Mul32F x (Const32F [f2i(-1)])) + // match: (Mul32F x (Const32F [auxFrom32F(-1)])) // cond: // result: (Neg32F x) for { @@ -18402,14 +18348,14 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { if v_1.Op != OpConst32F { break } - if v_1.AuxInt != f2i(-1) { + if v_1.AuxInt != auxFrom32F(-1) { break } v.reset(OpNeg32F) v.AddArg(x) return true } - // match: (Mul32F (Const32F [f2i(-1)]) x) + // match: (Mul32F (Const32F [auxFrom32F(-1)]) x) // cond: // result: (Neg32F x) for { @@ -18418,7 +18364,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { if v_0.Op != OpConst32F { break } - if v_0.AuxInt != f2i(-1) { + if v_0.AuxInt != auxFrom32F(-1) { break } x := v.Args[1] @@ -18426,7 +18372,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { v.AddArg(x) return true } - // match: (Mul32F x (Const32F [f2i(2)])) + // match: (Mul32F x (Const32F [auxFrom32F(2)])) // cond: // result: (Add32F x x) for { @@ -18436,7 +18382,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { if v_1.Op != OpConst32F { break } - if v_1.AuxInt != f2i(2) { + if v_1.AuxInt != auxFrom32F(2) { break } v.reset(OpAdd32F) @@ -18444,7 +18390,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { v.AddArg(x) return true } - // match: (Mul32F (Const32F [f2i(2)]) x) + // match: (Mul32F (Const32F [auxFrom32F(2)]) x) // cond: // result: (Add32F x x) for { @@ -18453,7 +18399,7 @@ func rewriteValuegeneric_OpMul32F_0(v *Value) bool { if v_0.Op != OpConst32F { break } - if v_0.AuxInt != f2i(2) { + if v_0.AuxInt != auxFrom32F(2) { break } x := v.Args[1] @@ -19001,7 +18947,7 @@ func rewriteValuegeneric_OpMul64_10(v *Value) bool { func rewriteValuegeneric_OpMul64F_0(v *Value) bool { // match: (Mul64F (Const64F [c]) (Const64F [d])) // cond: - // result: (Const64F [f2i(i2f(c) * i2f(d))]) + // result: (Const64F [auxFrom64F(auxTo64F(c) * auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -19015,12 +18961,12 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(i2f(c) * i2f(d)) + v.AuxInt = auxFrom64F(auxTo64F(c) * auxTo64F(d)) return true } // match: (Mul64F (Const64F [d]) (Const64F [c])) // cond: - // result: (Const64F [f2i(i2f(c) * i2f(d))]) + // result: (Const64F [auxFrom64F(auxTo64F(c) * auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -19034,10 +18980,10 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { } c := v_1.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(i2f(c) * i2f(d)) + v.AuxInt = auxFrom64F(auxTo64F(c) * auxTo64F(d)) return true } - // match: (Mul64F x (Const64F [f2i(1)])) + // match: (Mul64F x (Const64F [auxFrom64F(1)])) // cond: // result: x for { @@ -19047,7 +18993,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { if v_1.Op != OpConst64F { break } - if v_1.AuxInt != f2i(1) { + if v_1.AuxInt != auxFrom64F(1) { break } v.reset(OpCopy) @@ -19055,7 +19001,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { v.AddArg(x) return true } - // match: (Mul64F (Const64F [f2i(1)]) x) + // match: (Mul64F (Const64F [auxFrom64F(1)]) x) // cond: // result: x for { @@ -19064,7 +19010,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { if v_0.Op != OpConst64F { break } - if v_0.AuxInt != f2i(1) { + if v_0.AuxInt != auxFrom64F(1) { break } x := v.Args[1] @@ -19073,7 +19019,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { v.AddArg(x) return true } - // match: (Mul64F x (Const64F [f2i(-1)])) + // match: (Mul64F x (Const64F [auxFrom64F(-1)])) // cond: // result: (Neg64F x) for { @@ -19083,14 +19029,14 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { if v_1.Op != OpConst64F { break } - if v_1.AuxInt != f2i(-1) { + if v_1.AuxInt != auxFrom64F(-1) { break } v.reset(OpNeg64F) v.AddArg(x) return true } - // match: (Mul64F (Const64F [f2i(-1)]) x) + // match: (Mul64F (Const64F [auxFrom64F(-1)]) x) // cond: // result: (Neg64F x) for { @@ -19099,7 +19045,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { if v_0.Op != OpConst64F { break } - if v_0.AuxInt != f2i(-1) { + if v_0.AuxInt != auxFrom64F(-1) { break } x := v.Args[1] @@ -19107,7 +19053,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { v.AddArg(x) return true } - // match: (Mul64F x (Const64F [f2i(2)])) + // match: (Mul64F x (Const64F [auxFrom64F(2)])) // cond: // result: (Add64F x x) for { @@ -19117,7 +19063,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { if v_1.Op != OpConst64F { break } - if v_1.AuxInt != f2i(2) { + if v_1.AuxInt != auxFrom64F(2) { break } v.reset(OpAdd64F) @@ -19125,7 +19071,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { v.AddArg(x) return true } - // match: (Mul64F (Const64F [f2i(2)]) x) + // match: (Mul64F (Const64F [auxFrom64F(2)]) x) // cond: // result: (Add64F x x) for { @@ -19134,7 +19080,7 @@ func rewriteValuegeneric_OpMul64F_0(v *Value) bool { if v_0.Op != OpConst64F { break } - if v_0.AuxInt != f2i(2) { + if v_0.AuxInt != auxFrom64F(2) { break } x := v.Args[1] @@ -19585,19 +19531,19 @@ func rewriteValuegeneric_OpNeg32_0(v *Value) bool { } func rewriteValuegeneric_OpNeg32F_0(v *Value) bool { // match: (Neg32F (Const32F [c])) - // cond: i2f(c) != 0 - // result: (Const32F [f2i(-i2f(c))]) + // cond: auxTo32F(c) != 0 + // result: (Const32F [auxFrom32F(-auxTo32F(c))]) for { v_0 := v.Args[0] if v_0.Op != OpConst32F { break } c := v_0.AuxInt - if !(i2f(c) != 0) { + if !(auxTo32F(c) != 0) { break } v.reset(OpConst32F) - v.AuxInt = f2i(-i2f(c)) + v.AuxInt = auxFrom32F(-auxTo32F(c)) return true } return false @@ -19636,19 +19582,19 @@ func rewriteValuegeneric_OpNeg64_0(v *Value) bool { } func rewriteValuegeneric_OpNeg64F_0(v *Value) bool { // match: (Neg64F (Const64F [c])) - // cond: i2f(c) != 0 - // result: (Const64F [f2i(-i2f(c))]) + // cond: auxTo64F(c) != 0 + // result: (Const64F [auxFrom64F(-auxTo64F(c))]) for { v_0 := v.Args[0] if v_0.Op != OpConst64F { break } c := v_0.AuxInt - if !(i2f(c) != 0) { + if !(auxTo64F(c) != 0) { break } v.reset(OpConst64F) - v.AuxInt = f2i(-i2f(c)) + v.AuxInt = auxFrom64F(-auxTo64F(c)) return true } return false @@ -20164,7 +20110,7 @@ func rewriteValuegeneric_OpNeq32_0(v *Value) bool { func rewriteValuegeneric_OpNeq32F_0(v *Value) bool { // match: (Neq32F (Const32F [c]) (Const32F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) != i2f(d))]) + // result: (ConstBool [b2i(auxTo32F(c) != auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -20178,12 +20124,12 @@ func rewriteValuegeneric_OpNeq32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) != i2f(d)) + v.AuxInt = b2i(auxTo32F(c) != auxTo32F(d)) return true } // match: (Neq32F (Const32F [d]) (Const32F [c])) // cond: - // result: (ConstBool [b2i(i2f(c) != i2f(d))]) + // result: (ConstBool [b2i(auxTo32F(c) != auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -20197,7 +20143,7 @@ func rewriteValuegeneric_OpNeq32F_0(v *Value) bool { } c := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) != i2f(d)) + v.AuxInt = b2i(auxTo32F(c) != auxTo32F(d)) return true } return false @@ -20443,7 +20389,7 @@ func rewriteValuegeneric_OpNeq64_0(v *Value) bool { func rewriteValuegeneric_OpNeq64F_0(v *Value) bool { // match: (Neq64F (Const64F [c]) (Const64F [d])) // cond: - // result: (ConstBool [b2i(i2f(c) != i2f(d))]) + // result: (ConstBool [b2i(auxTo64F(c) != auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -20457,12 +20403,12 @@ func rewriteValuegeneric_OpNeq64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) != i2f(d)) + v.AuxInt = b2i(auxTo64F(c) != auxTo64F(d)) return true } // match: (Neq64F (Const64F [d]) (Const64F [c])) // cond: - // result: (ConstBool [b2i(i2f(c) != i2f(d))]) + // result: (ConstBool [b2i(auxTo64F(c) != auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -20476,7 +20422,7 @@ func rewriteValuegeneric_OpNeq64F_0(v *Value) bool { } c := v_1.AuxInt v.reset(OpConstBool) - v.AuxInt = b2i(i2f(c) != i2f(d)) + v.AuxInt = b2i(auxTo64F(c) != auxTo64F(d)) return true } return false @@ -21412,7 +21358,7 @@ func rewriteValuegeneric_OpNilCheck_0(v *Value) bool { return true } // match: (NilCheck (Load (OffPtr [c] (SP)) (StaticCall {sym} _)) _) - // cond: isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize() + config.RegSize && warnRule(fe.Debug_checknil() && v.Pos.Line() > 1, v, "removed nil check") + // cond: isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize() + config.RegSize && warnRule(fe.Debug_checknil(), v, "removed nil check") // result: (Invalid) for { _ = v.Args[1] @@ -21435,14 +21381,14 @@ func rewriteValuegeneric_OpNilCheck_0(v *Value) bool { break } sym := v_0_1.Aux - if !(isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize()+config.RegSize && warnRule(fe.Debug_checknil() && v.Pos.Line() > 1, v, "removed nil check")) { + if !(isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize()+config.RegSize && warnRule(fe.Debug_checknil(), v, "removed nil check")) { break } v.reset(OpInvalid) return true } // match: (NilCheck (OffPtr (Load (OffPtr [c] (SP)) (StaticCall {sym} _))) _) - // cond: isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize() + config.RegSize && warnRule(fe.Debug_checknil() && v.Pos.Line() > 1, v, "removed nil check") + // cond: isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize() + config.RegSize && warnRule(fe.Debug_checknil(), v, "removed nil check") // result: (Invalid) for { _ = v.Args[1] @@ -21469,7 +21415,7 @@ func rewriteValuegeneric_OpNilCheck_0(v *Value) bool { break } sym := v_0_0_1.Aux - if !(isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize()+config.RegSize && warnRule(fe.Debug_checknil() && v.Pos.Line() > 1, v, "removed nil check")) { + if !(isSameSym(sym, "runtime.newobject") && c == config.ctxt.FixedFrameSize()+config.RegSize && warnRule(fe.Debug_checknil(), v, "removed nil check")) { break } v.reset(OpInvalid) @@ -27601,7 +27547,7 @@ func rewriteValuegeneric_OpSlicemask_0(v *Value) bool { func rewriteValuegeneric_OpSqrt_0(v *Value) bool { // match: (Sqrt (Const64F [c])) // cond: - // result: (Const64F [f2i(math.Sqrt(i2f(c)))]) + // result: (Const64F [auxFrom64F(math.Sqrt(auxTo64F(c)))]) for { v_0 := v.Args[0] if v_0.Op != OpConst64F { @@ -27609,7 +27555,7 @@ func rewriteValuegeneric_OpSqrt_0(v *Value) bool { } c := v_0.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(math.Sqrt(i2f(c))) + v.AuxInt = auxFrom64F(math.Sqrt(auxTo64F(c))) return true } return false @@ -29824,7 +29770,7 @@ func rewriteValuegeneric_OpSub32_10(v *Value) bool { func rewriteValuegeneric_OpSub32F_0(v *Value) bool { // match: (Sub32F (Const32F [c]) (Const32F [d])) // cond: - // result: (Const32F [f2i(float64(i2f32(c) - i2f32(d)))]) + // result: (Const32F [auxFrom32F(auxTo32F(c) - auxTo32F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -29838,25 +29784,7 @@ func rewriteValuegeneric_OpSub32F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConst32F) - v.AuxInt = f2i(float64(i2f32(c) - i2f32(d))) - return true - } - // match: (Sub32F x (Const32F [0])) - // cond: - // result: x - for { - _ = v.Args[1] - x := v.Args[0] - v_1 := v.Args[1] - if v_1.Op != OpConst32F { - break - } - if v_1.AuxInt != 0 { - break - } - v.reset(OpCopy) - v.Type = x.Type - v.AddArg(x) + v.AuxInt = auxFrom32F(auxTo32F(c) - auxTo32F(d)) return true } return false @@ -30248,7 +30176,7 @@ func rewriteValuegeneric_OpSub64_10(v *Value) bool { func rewriteValuegeneric_OpSub64F_0(v *Value) bool { // match: (Sub64F (Const64F [c]) (Const64F [d])) // cond: - // result: (Const64F [f2i(i2f(c) - i2f(d))]) + // result: (Const64F [auxFrom64F(auxTo64F(c) - auxTo64F(d))]) for { _ = v.Args[1] v_0 := v.Args[0] @@ -30262,25 +30190,7 @@ func rewriteValuegeneric_OpSub64F_0(v *Value) bool { } d := v_1.AuxInt v.reset(OpConst64F) - v.AuxInt = f2i(i2f(c) - i2f(d)) - return true - } - // match: (Sub64F x (Const64F [0])) - // cond: - // result: x - for { - _ = v.Args[1] - x := v.Args[0] - v_1 := v.Args[1] - if v_1.Op != OpConst64F { - break - } - if v_1.AuxInt != 0 { - break - } - v.reset(OpCopy) - v.Type = x.Type - v.AddArg(x) + v.AuxInt = auxFrom64F(auxTo64F(c) - auxTo64F(d)) return true } return false diff --git a/src/cmd/compile/internal/ssa/softfloat.go b/src/cmd/compile/internal/ssa/softfloat.go index 39829b046c..b41819c6ad 100644 --- a/src/cmd/compile/internal/ssa/softfloat.go +++ b/src/cmd/compile/internal/ssa/softfloat.go @@ -25,7 +25,7 @@ func softfloat(f *Func) { case OpConst32F: v.Op = OpConst32 v.Type = f.Config.Types.UInt32 - v.AuxInt = int64(int32(math.Float32bits(i2f32(v.AuxInt)))) + v.AuxInt = int64(int32(math.Float32bits(auxTo32F(v.AuxInt)))) case OpConst64F: v.Op = OpConst64 v.Type = f.Config.Types.UInt64 diff --git a/src/cmd/compile/internal/ssa/stmtlines_test.go b/src/cmd/compile/internal/ssa/stmtlines_test.go index 1081f83f6d..c0fc7adab5 100644 --- a/src/cmd/compile/internal/ssa/stmtlines_test.go +++ b/src/cmd/compile/internal/ssa/stmtlines_test.go @@ -62,6 +62,9 @@ func TestStmtLines(t *testing.T) { if pkgname == "runtime" { continue } + if e.Val(dwarf.AttrStmtList) == nil { + continue + } lrdr, err := dw.LineReader(e) must(err) diff --git a/src/cmd/compile/internal/ssa/testdata/hist.gdb-opt.nexts b/src/cmd/compile/internal/ssa/testdata/hist.gdb-opt.nexts index ad2719185e..6586f243e2 100644 --- a/src/cmd/compile/internal/ssa/testdata/hist.gdb-opt.nexts +++ b/src/cmd/compile/internal/ssa/testdata/hist.gdb-opt.nexts @@ -19,7 +19,7 @@ dy = <Optimized out, as expected> 65: if len(os.Args) > 1 { 73: scanner := bufio.NewScanner(reader) 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -29,7 +29,7 @@ i = 1 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -39,7 +39,7 @@ i = 1 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -49,7 +49,7 @@ i = 1 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -59,7 +59,7 @@ i = 2 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -69,7 +69,7 @@ i = 2 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -79,7 +79,7 @@ i = 2 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -89,7 +89,7 @@ i = 4 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -99,7 +99,7 @@ i = 4 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 75: s := scanner.Text() 76: i, err := strconv.ParseInt(s, 10, 64) 77: if err != nil { //gdb-dbg=(i) //gdb-opt=(err,hist,i) @@ -109,7 +109,7 @@ i = 5 81: hist = ensure(int(i), hist) 82: hist[int(i)]++ 74: for scanner.Scan() { //gdb-opt=(scanner/A) -scanner = (struct bufio.Scanner *) <A> +scanner = (bufio.Scanner *) <A> 86: for i, a := range hist { 87: if a == 0 { //gdb-opt=(a,n,t) a = 0 diff --git a/src/cmd/compile/internal/types/type.go b/src/cmd/compile/internal/types/type.go index d367cd1944..25f8f826e6 100644 --- a/src/cmd/compile/internal/types/type.go +++ b/src/cmd/compile/internal/types/type.go @@ -817,7 +817,7 @@ func (t *Type) ChanArgs() *Type { return t.Extra.(ChanArgs).T } -// FuncArgs returns the channel type for TFUNCARGS type t. +// FuncArgs returns the func type for TFUNCARGS type t. func (t *Type) FuncArgs() *Type { t.wantEtype(TFUNCARGS) return t.Extra.(FuncArgs).T diff --git a/src/cmd/compile/internal/x86/ssa.go b/src/cmd/compile/internal/x86/ssa.go index a53b63ab92..e0bb4418ec 100644 --- a/src/cmd/compile/internal/x86/ssa.go +++ b/src/cmd/compile/internal/x86/ssa.go @@ -547,22 +547,22 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) { p.To.Reg = v.Args[0].Reg() gc.AddAux(&p.To, v) case ssa.Op386ADDLconstmodify: - var p *obj.Prog = nil sc := v.AuxValAndOff() - off := sc.Off() val := sc.Val() - if val == 1 { - p = s.Prog(x86.AINCL) - } else if val == -1 { - p = s.Prog(x86.ADECL) - } else { - p = s.Prog(v.Op.Asm()) - p.From.Type = obj.TYPE_CONST - p.From.Offset = val + if val == 1 || val == -1 { + var p *obj.Prog + if val == 1 { + p = s.Prog(x86.AINCL) + } else { + p = s.Prog(x86.ADECL) + } + off := sc.Off() + p.To.Type = obj.TYPE_MEM + p.To.Reg = v.Args[0].Reg() + gc.AddAux2(&p.To, v, off) + break } - p.To.Type = obj.TYPE_MEM - p.To.Reg = v.Args[0].Reg() - gc.AddAux2(&p.To, v, off) + fallthrough case ssa.Op386ANDLconstmodify, ssa.Op386ORLconstmodify, ssa.Op386XORLconstmodify: sc := v.AuxValAndOff() off := sc.Off() diff --git a/src/cmd/dist/build.go b/src/cmd/dist/build.go index d4f9dc4fbb..49f4a5e6a7 100644 --- a/src/cmd/dist/build.go +++ b/src/cmd/dist/build.go @@ -69,6 +69,7 @@ var okgoarch = []string{ "ppc64le", "riscv64", "s390x", + "sparc64", "wasm", } @@ -86,6 +87,7 @@ var okgoos = []string{ "openbsd", "plan9", "windows", + "aix", } // find reports the first index of p in l[0:n], or else -1. @@ -1387,6 +1389,7 @@ func checkNotStale(goBinary string, targets ...string) { // single point of truth for supported platforms. This list is used // by 'go tool dist list'. var cgoEnabled = map[string]bool{ + "aix/ppc64": false, "darwin/386": true, "darwin/amd64": true, "darwin/arm": true, @@ -1407,6 +1410,7 @@ var cgoEnabled = map[string]bool{ "linux/mips64le": true, "linux/riscv64": true, "linux/s390x": true, + "linux/sparc64": true, "android/386": true, "android/amd64": true, "android/arm": true, diff --git a/src/cmd/dist/buildruntime.go b/src/cmd/dist/buildruntime.go index acf2230cb4..10d1552c94 100644 --- a/src/cmd/dist/buildruntime.go +++ b/src/cmd/dist/buildruntime.go @@ -87,6 +87,10 @@ func mkzbootstrap(file string) { // stack guard size. Larger multipliers are used for non-optimized // builds that have larger stack frames. func stackGuardMultiplier() int { + // On AIX, a larger stack is needed for syscalls + if goos == "aix" { + return 2 + } for _, s := range strings.Split(os.Getenv("GO_GCFLAGS"), " ") { if s == "-N" { return 2 diff --git a/src/cmd/dist/main.go b/src/cmd/dist/main.go index 37e37e2733..bf08869afb 100644 --- a/src/cmd/dist/main.go +++ b/src/cmd/dist/main.go @@ -81,6 +81,9 @@ func main() { } case "windows": exe = ".exe" + case "aix": + // uname -m doesn't work under AIX + gohostarch = "ppc64" } sysinit() diff --git a/src/cmd/dist/test.go b/src/cmd/dist/test.go index 4cd854773f..2d7f7bd2f9 100644 --- a/src/cmd/dist/test.go +++ b/src/cmd/dist/test.go @@ -1469,8 +1469,10 @@ func (t *tester) packageHasBenchmarks(pkg string) bool { // because cmd/dist has to be buildable by Go 1.4. func raceDetectorSupported(goos, goarch string) bool { switch goos { - case "linux", "darwin", "freebsd", "netbsd", "windows": + case "linux": return goarch == "amd64" || goarch == "ppc64le" + case "darwin", "freebsd", "netbsd", "windows": + return goarch == "amd64" default: return false } diff --git a/src/cmd/fix/main.go b/src/cmd/fix/main.go index f06abae171..f54a5e0d96 100644 --- a/src/cmd/fix/main.go +++ b/src/cmd/fix/main.go @@ -52,7 +52,7 @@ func usage() { fmt.Fprintf(os.Stderr, "\n%s\n", f.name) } desc := strings.TrimSpace(f.desc) - desc = strings.Replace(desc, "\n", "\n\t", -1) + desc = strings.ReplaceAll(desc, "\n", "\n\t") fmt.Fprintf(os.Stderr, "\t%s\n", desc) } os.Exit(2) diff --git a/src/cmd/fix/typecheck.go b/src/cmd/fix/typecheck.go index eafb626c74..66e0cdcec0 100644 --- a/src/cmd/fix/typecheck.go +++ b/src/cmd/fix/typecheck.go @@ -193,12 +193,12 @@ func typecheck(cfg *TypeConfig, f *ast.File) (typeof map[interface{}]string, ass var params, results []string for _, p := range fn.Type.Params.List { t := gofmt(p.Type) - t = strings.Replace(t, "_Ctype_", "C.", -1) + t = strings.ReplaceAll(t, "_Ctype_", "C.") params = append(params, t) } for _, r := range fn.Type.Results.List { t := gofmt(r.Type) - t = strings.Replace(t, "_Ctype_", "C.", -1) + t = strings.ReplaceAll(t, "_Ctype_", "C.") results = append(results, t) } cfg.External["C."+fn.Name.Name[7:]] = joinFunc(params, results) diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go index 35cabcac14..9528ca2984 100644 --- a/src/cmd/go/alldocs.go +++ b/src/cmd/go/alldocs.go @@ -144,7 +144,7 @@ // link against shared libraries previously created with // -buildmode=shared. // -mod mode -// module download mode to use: readonly, release, or vendor. +// module download mode to use: readonly or vendor. // See 'go help modules' for more. // -pkgdir dir // install and load all packages from dir instead of the usual locations. @@ -1449,6 +1449,12 @@ // The directory where the go command will write // temporary source files, packages, and binaries. // +// Each entry in the GOFLAGS list must be a standalone flag. +// Because the entries are space-separated, flag values must +// not contain spaces. In some cases, you can provide multiple flag +// values instead: for example, to set '-ldflags=-s -w' +// you can use 'GOFLAGS=-ldflags=-s -ldflags=-w'. +// // Environment variables for use with cgo: // // CC diff --git a/src/cmd/go/go_test.go b/src/cmd/go/go_test.go index 85dcada9ec..73d7663ad6 100644 --- a/src/cmd/go/go_test.go +++ b/src/cmd/go/go_test.go @@ -1074,6 +1074,8 @@ func testMove(t *testing.T, vcs, url, base, config string) { defer tg.cleanup() tg.parallel() tg.tempDir("src") + tg.must(os.Mkdir(tg.path(".hg"), 0700)) + tg.must(ioutil.WriteFile(filepath.Join(tg.path(".hg"), "hgrc"), nil, 0600)) tg.setenv("GOPATH", tg.path(".")) tg.run("get", "-d", url) tg.run("get", "-d", "-u", url) @@ -1088,7 +1090,7 @@ func testMove(t *testing.T, vcs, url, base, config string) { path := tg.path(filepath.Join("src", config)) data, err := ioutil.ReadFile(path) tg.must(err) - data = bytes.Replace(data, []byte(base), []byte(base+"XXX"), -1) + data = bytes.ReplaceAll(data, []byte(base), []byte(base+"XXX")) tg.must(ioutil.WriteFile(path, data, 0644)) } if vcs == "git" { @@ -1185,6 +1187,7 @@ func TestImportCycle(t *testing.T) { } func TestListImportMap(t *testing.T) { + skipIfGccgo(t, "gccgo does not have standard packages") tg := testgo(t) defer tg.cleanup() tg.parallel() @@ -1418,6 +1421,7 @@ func TestRelativeGOBINFail(t *testing.T) { defer tg.cleanup() tg.tempFile("triv.go", `package main; func main() {}`) tg.setenv("GOBIN", ".") + tg.cd(tg.path(".")) tg.runFail("install") tg.grepStderr("cannot install, GOBIN must be an absolute path", "go install must fail if $GOBIN is a relative path") } @@ -1729,20 +1733,23 @@ func TestGoListDeps(t *testing.T) { tg.run("list", "-deps", "p1") tg.grepStdout("p1/p2/p3/p4", "-deps p1 does not mention p4") - // Check the list is in dependency order. - tg.run("list", "-deps", "math") - want := "internal/cpu\nunsafe\nmath\n" - out := tg.stdout.String() - if !strings.Contains(out, "internal/cpu") { - // Some systems don't use internal/cpu. - want = "unsafe\nmath\n" - } - if tg.stdout.String() != want { - t.Fatalf("list -deps math: wrong order\nhave %q\nwant %q", tg.stdout.String(), want) + if runtime.Compiler != "gccgo" { + // Check the list is in dependency order. + tg.run("list", "-deps", "math") + want := "internal/cpu\nunsafe\nmath\n" + out := tg.stdout.String() + if !strings.Contains(out, "internal/cpu") { + // Some systems don't use internal/cpu. + want = "unsafe\nmath\n" + } + if tg.stdout.String() != want { + t.Fatalf("list -deps math: wrong order\nhave %q\nwant %q", tg.stdout.String(), want) + } } } func TestGoListTest(t *testing.T) { + skipIfGccgo(t, "gccgo does not have standard packages") tg := testgo(t) defer tg.cleanup() tg.parallel() @@ -1815,6 +1822,7 @@ func TestGoListCompiledCgo(t *testing.T) { } func TestGoListExport(t *testing.T) { + skipIfGccgo(t, "gccgo does not have standard packages") tg := testgo(t) defer tg.cleanup() tg.parallel() @@ -2051,6 +2059,7 @@ func TestGoTestCpuprofileLeavesBinaryBehind(t *testing.T) { } func TestGoTestCpuprofileDashOControlsBinaryLocation(t *testing.T) { + skipIfGccgo(t, "gccgo has no standard packages") tooSlow(t) tg := testgo(t) defer tg.cleanup() @@ -2107,6 +2116,7 @@ func TestGoTestDashCDashOControlsBinaryLocation(t *testing.T) { } func TestGoTestDashOWritesBinary(t *testing.T) { + skipIfGccgo(t, "gccgo has no standard packages") tooSlow(t) tg := testgo(t) defer tg.cleanup() @@ -2350,14 +2360,14 @@ func TestShadowingLogic(t *testing.T) { // The math in root1 is not "math" because the standard math is. tg.run("list", "-f", "({{.ImportPath}}) ({{.ConflictDir}})", "./testdata/shadow/root1/src/math") - pwdForwardSlash := strings.Replace(pwd, string(os.PathSeparator), "/", -1) + pwdForwardSlash := strings.ReplaceAll(pwd, string(os.PathSeparator), "/") if !strings.HasPrefix(pwdForwardSlash, "/") { pwdForwardSlash = "/" + pwdForwardSlash } // The output will have makeImportValid applies, but we only // bother to deal with characters we might reasonably see. for _, r := range " :" { - pwdForwardSlash = strings.Replace(pwdForwardSlash, string(r), "_", -1) + pwdForwardSlash = strings.ReplaceAll(pwdForwardSlash, string(r), "_") } want := "(_" + pwdForwardSlash + "/testdata/shadow/root1/src/math) (" + filepath.Join(runtime.GOROOT(), "src", "math") + ")" if strings.TrimSpace(tg.getStdout()) != want { @@ -2402,6 +2412,7 @@ func checkCoverage(tg *testgoData, data string) { } func TestCoverageRuns(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tooSlow(t) tg := testgo(t) defer tg.cleanup() @@ -2413,6 +2424,7 @@ func TestCoverageRuns(t *testing.T) { } func TestCoverageDotImport(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tg := testgo(t) defer tg.cleanup() tg.parallel() @@ -2425,6 +2437,7 @@ func TestCoverageDotImport(t *testing.T) { // Check that coverage analysis uses set mode. // Also check that coverage profiles merge correctly. func TestCoverageUsesSetMode(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tooSlow(t) tg := testgo(t) defer tg.cleanup() @@ -2455,6 +2468,7 @@ func TestCoverageUsesAtomicModeForRace(t *testing.T) { if !canRace { t.Skip("skipping because race detector not supported") } + skipIfGccgo(t, "gccgo has no cover tool") tg := testgo(t) defer tg.cleanup() @@ -2472,6 +2486,7 @@ func TestCoverageUsesAtomicModeForRace(t *testing.T) { } func TestCoverageSyncAtomicImport(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tooSlow(t) tg := testgo(t) defer tg.cleanup() @@ -2493,6 +2508,7 @@ func TestCoverageDepLoop(t *testing.T) { } func TestCoverageImportMainLoop(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tg := testgo(t) defer tg.cleanup() tg.setenv("GOPATH", filepath.Join(tg.pwd(), "testdata")) @@ -2503,6 +2519,7 @@ func TestCoverageImportMainLoop(t *testing.T) { } func TestCoveragePattern(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tooSlow(t) tg := testgo(t) defer tg.cleanup() @@ -2518,6 +2535,7 @@ func TestCoveragePattern(t *testing.T) { } func TestCoverageErrorLine(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tooSlow(t) tg := testgo(t) defer tg.cleanup() @@ -2539,7 +2557,7 @@ func TestCoverageErrorLine(t *testing.T) { // It's OK that stderr2 drops the character position in the error, // because of the //line directive (see golang.org/issue/22662). - stderr = strings.Replace(stderr, "p.go:4:2:", "p.go:4:", -1) + stderr = strings.ReplaceAll(stderr, "p.go:4:2:", "p.go:4:") if stderr != stderr2 { t.Logf("test -cover changed error messages:\nbefore:\n%s\n\nafter:\n%s", stderr, stderr2) t.Skip("golang.org/issue/22660") @@ -2561,6 +2579,7 @@ func TestTestBuildFailureOutput(t *testing.T) { } func TestCoverageFunc(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tooSlow(t) tg := testgo(t) defer tg.cleanup() @@ -2576,6 +2595,7 @@ func TestCoverageFunc(t *testing.T) { // Issue 24588. func TestCoverageDashC(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tg := testgo(t) defer tg.cleanup() tg.parallel() @@ -2684,6 +2704,7 @@ func main() { } func TestCoverageWithCgo(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tooSlow(t) if !canCgo { t.Skip("skipping because cgo not enabled") @@ -5164,6 +5185,7 @@ func TestCacheCoverage(t *testing.T) { } func TestCacheVet(t *testing.T) { + skipIfGccgo(t, "gccgo has no standard packages") tg := testgo(t) defer tg.cleanup() tg.parallel() @@ -6082,6 +6104,7 @@ func TestNoRelativeTmpdir(t *testing.T) { // Issue 24704. func TestLinkerTmpDirIsDeleted(t *testing.T) { + skipIfGccgo(t, "gccgo does not use cmd/link") if !canCgo { t.Skip("skipping because cgo not enabled") } @@ -6129,6 +6152,7 @@ func TestLinkerTmpDirIsDeleted(t *testing.T) { } func testCDAndGOPATHAreDifferent(tg *testgoData, cd, gopath string) { + skipIfGccgo(tg.t, "gccgo does not support -ldflags -X") tg.setenv("GOPATH", gopath) tg.tempDir("dir") @@ -6155,7 +6179,7 @@ func TestCDAndGOPATHAreDifferent(t *testing.T) { testCDAndGOPATHAreDifferent(tg, cd, gopath) if runtime.GOOS == "windows" { - testCDAndGOPATHAreDifferent(tg, cd, strings.Replace(gopath, `\`, `/`, -1)) + testCDAndGOPATHAreDifferent(tg, cd, strings.ReplaceAll(gopath, `\`, `/`)) testCDAndGOPATHAreDifferent(tg, cd, strings.ToUpper(gopath)) testCDAndGOPATHAreDifferent(tg, cd, strings.ToLower(gopath)) } @@ -6184,6 +6208,7 @@ func TestGoBuildDashODevNull(t *testing.T) { // Issue 25093. func TestCoverpkgTestOnly(t *testing.T) { + skipIfGccgo(t, "gccgo has no cover tool") tg := testgo(t) defer tg.cleanup() tg.parallel() diff --git a/src/cmd/go/internal/clean/clean.go b/src/cmd/go/internal/clean/clean.go index d023592eed..b12bd981a7 100644 --- a/src/cmd/go/internal/clean/clean.go +++ b/src/cmd/go/internal/clean/clean.go @@ -112,9 +112,10 @@ func runClean(cmd *base.Command, args []string) { } } + var b work.Builder + b.Print = fmt.Print + if cleanCache { - var b work.Builder - b.Print = fmt.Print dir := cache.DefaultDir() if dir != "off" { // Remove the cache subdirectories but not the top cache directory. @@ -156,8 +157,13 @@ func runClean(cmd *base.Command, args []string) { if modfetch.PkgMod == "" { base.Fatalf("go clean -modcache: no module cache") } - if err := removeAll(modfetch.PkgMod); err != nil { - base.Errorf("go clean -modcache: %v", err) + if cfg.BuildN || cfg.BuildX { + b.Showcmd("", "rm -rf %s", modfetch.PkgMod) + } + if !cfg.BuildN { + if err := removeAll(modfetch.PkgMod); err != nil { + base.Errorf("go clean -modcache: %v", err) + } } } } diff --git a/src/cmd/go/internal/envcmd/env.go b/src/cmd/go/internal/envcmd/env.go index afadbade38..85a42e0519 100644 --- a/src/cmd/go/internal/envcmd/env.go +++ b/src/cmd/go/internal/envcmd/env.go @@ -203,7 +203,7 @@ func runEnv(cmd *base.Command, args []string) { fmt.Printf("%s=\"%s\"\n", e.Name, e.Value) case "plan9": if strings.IndexByte(e.Value, '\x00') < 0 { - fmt.Printf("%s='%s'\n", e.Name, strings.Replace(e.Value, "'", "''", -1)) + fmt.Printf("%s='%s'\n", e.Name, strings.ReplaceAll(e.Value, "'", "''")) } else { v := strings.Split(e.Value, "\x00") fmt.Printf("%s=(", e.Name) diff --git a/src/cmd/go/internal/get/vcs.go b/src/cmd/go/internal/get/vcs.go index 0f7b623ec3..173934b84e 100644 --- a/src/cmd/go/internal/get/vcs.go +++ b/src/cmd/go/internal/get/vcs.go @@ -964,7 +964,7 @@ func matchGoImport(imports []metaImport, importPath string) (metaImport, error) // expand rewrites s to replace {k} with match[k] for each key k in match. func expand(match map[string]string, s string) string { for k, v := range match { - s = strings.Replace(s, "{"+k+"}", v, -1) + s = strings.ReplaceAll(s, "{"+k+"}", v) } return s } diff --git a/src/cmd/go/internal/help/helpdoc.go b/src/cmd/go/internal/help/helpdoc.go index aff4ce12f6..e2c4e61615 100644 --- a/src/cmd/go/internal/help/helpdoc.go +++ b/src/cmd/go/internal/help/helpdoc.go @@ -507,6 +507,12 @@ General-purpose environment variables: The directory where the go command will write temporary source files, packages, and binaries. +Each entry in the GOFLAGS list must be a standalone flag. +Because the entries are space-separated, flag values must +not contain spaces. In some cases, you can provide multiple flag +values instead: for example, to set '-ldflags=-s -w' +you can use 'GOFLAGS=-ldflags=-s -ldflags=-w'. + Environment variables for use with cgo: CC diff --git a/src/cmd/go/internal/modconv/convert_test.go b/src/cmd/go/internal/modconv/convert_test.go index ad27abb8ef..4d55d73f21 100644 --- a/src/cmd/go/internal/modconv/convert_test.go +++ b/src/cmd/go/internal/modconv/convert_test.go @@ -146,7 +146,7 @@ func TestConvertLegacyConfig(t *testing.T) { } for _, tt := range tests { - t.Run(strings.Replace(tt.path, "/", "_", -1)+"_"+tt.vers, func(t *testing.T) { + t.Run(strings.ReplaceAll(tt.path, "/", "_")+"_"+tt.vers, func(t *testing.T) { f, err := modfile.Parse("golden", []byte(tt.gomod), nil) if err != nil { t.Fatal(err) diff --git a/src/cmd/go/internal/modfetch/codehost/codehost.go b/src/cmd/go/internal/modfetch/codehost/codehost.go index 4103ddc717..4205cd26bd 100644 --- a/src/cmd/go/internal/modfetch/codehost/codehost.go +++ b/src/cmd/go/internal/modfetch/codehost/codehost.go @@ -185,7 +185,7 @@ func (e *RunError) Error() string { text := e.Cmd + ": " + e.Err.Error() stderr := bytes.TrimRight(e.Stderr, "\n") if len(stderr) > 0 { - text += ":\n\t" + strings.Replace(string(stderr), "\n", "\n\t", -1) + text += ":\n\t" + strings.ReplaceAll(string(stderr), "\n", "\n\t") } return text } diff --git a/src/cmd/go/internal/modfetch/coderepo_test.go b/src/cmd/go/internal/modfetch/coderepo_test.go index 79b82786cb..73c4bd2cca 100644 --- a/src/cmd/go/internal/modfetch/coderepo_test.go +++ b/src/cmd/go/internal/modfetch/coderepo_test.go @@ -423,7 +423,7 @@ func TestCodeRepo(t *testing.T) { } } } - t.Run(strings.Replace(tt.path, "/", "_", -1)+"/"+tt.rev, f) + t.Run(strings.ReplaceAll(tt.path, "/", "_")+"/"+tt.rev, f) if strings.HasPrefix(tt.path, vgotest1git) { for _, alt := range altVgotests { // Note: Communicating with f through tt; should be cleaned up. @@ -442,7 +442,7 @@ func TestCodeRepo(t *testing.T) { tt.rev = remap(tt.rev, m) tt.gomoderr = remap(tt.gomoderr, m) tt.ziperr = remap(tt.ziperr, m) - t.Run(strings.Replace(tt.path, "/", "_", -1)+"/"+tt.rev, f) + t.Run(strings.ReplaceAll(tt.path, "/", "_")+"/"+tt.rev, f) tt = old } } @@ -473,9 +473,9 @@ func remap(name string, m map[string]string) string { } } for k, v := range m { - name = strings.Replace(name, k, v, -1) + name = strings.ReplaceAll(name, k, v) if codehost.AllHex(k) { - name = strings.Replace(name, k[:12], v[:12], -1) + name = strings.ReplaceAll(name, k[:12], v[:12]) } } return name @@ -505,11 +505,11 @@ var codeRepoVersionsTests = []struct { }, { path: "gopkg.in/russross/blackfriday.v2", - versions: []string{"v2.0.0"}, + versions: []string{"v2.0.0", "v2.0.1"}, }, { path: "gopkg.in/natefinch/lumberjack.v2", - versions: nil, + versions: []string{"v2.0.0"}, }, } @@ -522,7 +522,7 @@ func TestCodeRepoVersions(t *testing.T) { } defer os.RemoveAll(tmpdir) for _, tt := range codeRepoVersionsTests { - t.Run(strings.Replace(tt.path, "/", "_", -1), func(t *testing.T) { + t.Run(strings.ReplaceAll(tt.path, "/", "_"), func(t *testing.T) { repo, err := Lookup(tt.path) if err != nil { t.Fatalf("Lookup(%q): %v", tt.path, err) @@ -570,7 +570,7 @@ func TestLatest(t *testing.T) { } defer os.RemoveAll(tmpdir) for _, tt := range latestTests { - name := strings.Replace(tt.path, "/", "_", -1) + name := strings.ReplaceAll(tt.path, "/", "_") t.Run(name, func(t *testing.T) { repo, err := Lookup(tt.path) if err != nil { diff --git a/src/cmd/go/internal/modfetch/fetch.go b/src/cmd/go/internal/modfetch/fetch.go index 2e26bac434..8485932b42 100644 --- a/src/cmd/go/internal/modfetch/fetch.go +++ b/src/cmd/go/internal/modfetch/fetch.go @@ -123,7 +123,7 @@ func downloadZip(mod module.Version, target string) error { for _, f := range z.File { if !strings.HasPrefix(f.Name, prefix) { z.Close() - return fmt.Errorf("zip for %s has unexpected file %s", prefix[:len(prefix)-1], f.Name) + return fmt.Errorf("zip for %s has unexpected file %s", prefix, f.Name) } } z.Close() diff --git a/src/cmd/go/internal/modfetch/proxy.go b/src/cmd/go/internal/modfetch/proxy.go index 5f856b80d2..7c78502f31 100644 --- a/src/cmd/go/internal/modfetch/proxy.go +++ b/src/cmd/go/internal/modfetch/proxy.go @@ -248,5 +248,5 @@ func (p *proxyRepo) Zip(version string, tmpdir string) (tmpfile string, err erro // That is, it escapes things like ? and # (which really shouldn't appear anyway). // It does not escape / to %2F: our REST API is designed so that / can be left as is. func pathEscape(s string) string { - return strings.Replace(url.PathEscape(s), "%2F", "/", -1) + return strings.ReplaceAll(url.PathEscape(s), "%2F", "/") } diff --git a/src/cmd/go/internal/modload/build.go b/src/cmd/go/internal/modload/build.go index cebb802db9..acee4a91e7 100644 --- a/src/cmd/go/internal/modload/build.go +++ b/src/cmd/go/internal/modload/build.go @@ -14,6 +14,7 @@ import ( "cmd/go/internal/search" "encoding/hex" "fmt" + "internal/goroot" "os" "path/filepath" "strings" @@ -30,13 +31,11 @@ func isStandardImportPath(path string) bool { func findStandardImportPath(path string) string { if search.IsStandardImportPath(path) { - dir := filepath.Join(cfg.GOROOT, "src", path) - if _, err := os.Stat(dir); err == nil { - return dir + if goroot.IsStandardPackage(cfg.GOROOT, cfg.BuildContext.Compiler, path) { + return filepath.Join(cfg.GOROOT, "src", path) } - dir = filepath.Join(cfg.GOROOT, "src/vendor", path) - if _, err := os.Stat(dir); err == nil { - return dir + if goroot.IsStandardPackage(cfg.GOROOT, cfg.BuildContext.Compiler, "vendor/"+path) { + return filepath.Join(cfg.GOROOT, "src/vendor", path) } } return "" @@ -232,11 +231,16 @@ func findModule(target, path string) module.Version { } func ModInfoProg(info string) []byte { + // Inject a variable with the debug information as runtime/debug.modinfo, + // but compile it in package main so that it is specific to the binary. + // Populate it in an init func so that it will work with go:linkname, + // but use a string constant instead of the name 'string' in case + // package main shadows the built-in 'string' with some local declaration. return []byte(fmt.Sprintf(` package main import _ "unsafe" //go:linkname __debug_modinfo__ runtime/debug.modinfo - var __debug_modinfo__ string + var __debug_modinfo__ = "" func init() { __debug_modinfo__ = %q } diff --git a/src/cmd/go/internal/modload/import.go b/src/cmd/go/internal/modload/import.go index 12d9407f6e..44c2a23726 100644 --- a/src/cmd/go/internal/modload/import.go +++ b/src/cmd/go/internal/modload/import.go @@ -9,6 +9,7 @@ import ( "errors" "fmt" "go/build" + "internal/goroot" "os" "path/filepath" "strings" @@ -60,8 +61,8 @@ func Import(path string) (m module.Version, dir string, err error) { if strings.HasPrefix(path, "golang_org/") { return module.Version{}, filepath.Join(cfg.GOROOT, "src/vendor", path), nil } - dir := filepath.Join(cfg.GOROOT, "src", path) - if _, err := os.Stat(dir); err == nil { + if goroot.IsStandardPackage(cfg.GOROOT, cfg.BuildContext.Compiler, path) { + dir := filepath.Join(cfg.GOROOT, "src", path) return module.Version{}, dir, nil } } diff --git a/src/cmd/go/internal/modload/import_test.go b/src/cmd/go/internal/modload/import_test.go index 3f4ddab436..9422a3d960 100644 --- a/src/cmd/go/internal/modload/import_test.go +++ b/src/cmd/go/internal/modload/import_test.go @@ -45,7 +45,7 @@ func TestImport(t *testing.T) { testenv.MustHaveExternalNetwork(t) for _, tt := range importTests { - t.Run(strings.Replace(tt.path, "/", "_", -1), func(t *testing.T) { + t.Run(strings.ReplaceAll(tt.path, "/", "_"), func(t *testing.T) { // Note that there is no build list, so Import should always fail. m, dir, err := Import(tt.path) if err == nil { diff --git a/src/cmd/go/internal/modload/query.go b/src/cmd/go/internal/modload/query.go index 3b550f1db7..4071341313 100644 --- a/src/cmd/go/internal/modload/query.go +++ b/src/cmd/go/internal/modload/query.go @@ -207,7 +207,7 @@ func matchSemverPrefix(p, v string) bool { // If multiple modules with revisions matching the query provide the requested // package, QueryPackage picks the one with the longest module path. // -// If the path is in the the main module and the query is "latest", +// If the path is in the main module and the query is "latest", // QueryPackage returns Target as the version. func QueryPackage(path, query string, allowed func(module.Version) bool) (module.Version, *modfetch.RevInfo, error) { if _, ok := dirInModule(path, Target.Path, ModRoot, true); ok { @@ -221,7 +221,7 @@ func QueryPackage(path, query string, allowed func(module.Version) bool) (module } finalErr := errMissing - for p := path; p != "."; p = pathpkg.Dir(p) { + for p := path; p != "." && p != "/"; p = pathpkg.Dir(p) { info, err := Query(p, query, allowed) if err != nil { if _, ok := err.(*codehost.VCSError); ok { diff --git a/src/cmd/go/internal/modload/query_test.go b/src/cmd/go/internal/modload/query_test.go index 7f3ffabef7..9b07383217 100644 --- a/src/cmd/go/internal/modload/query_test.go +++ b/src/cmd/go/internal/modload/query_test.go @@ -132,7 +132,7 @@ func TestQuery(t *testing.T) { ok, _ := path.Match(allow, m.Version) return ok } - t.Run(strings.Replace(tt.path, "/", "_", -1)+"/"+tt.query+"/"+allow, func(t *testing.T) { + t.Run(strings.ReplaceAll(tt.path, "/", "_")+"/"+tt.query+"/"+allow, func(t *testing.T) { info, err := Query(tt.path, tt.query, allowed) if tt.err != "" { if err != nil && err.Error() == tt.err { diff --git a/src/cmd/go/internal/search/search.go b/src/cmd/go/internal/search/search.go index 60ae73696b..0ca60e7349 100644 --- a/src/cmd/go/internal/search/search.go +++ b/src/cmd/go/internal/search/search.go @@ -275,7 +275,7 @@ func MatchPattern(pattern string) func(name string) bool { case strings.HasSuffix(re, `/\.\.\.`): re = strings.TrimSuffix(re, `/\.\.\.`) + `(/\.\.\.)?` } - re = strings.Replace(re, `\.\.\.`, `[^`+vendorChar+`]*`, -1) + re = strings.ReplaceAll(re, `\.\.\.`, `[^`+vendorChar+`]*`) reg := regexp.MustCompile(`^` + re + `$`) @@ -353,7 +353,7 @@ func CleanPatterns(patterns []string) []string { // as a courtesy to Windows developers, rewrite \ to / // in command-line arguments. Handles .\... and so on. if filepath.Separator == '\\' { - a = strings.Replace(a, `\`, `/`, -1) + a = strings.ReplaceAll(a, `\`, `/`) } // Put argument in canonical form, but preserve leading ./. diff --git a/src/cmd/go/internal/work/build.go b/src/cmd/go/internal/work/build.go index ed41ce5d07..145b87513a 100644 --- a/src/cmd/go/internal/work/build.go +++ b/src/cmd/go/internal/work/build.go @@ -99,7 +99,7 @@ and test commands: link against shared libraries previously created with -buildmode=shared. -mod mode - module download mode to use: readonly, release, or vendor. + module download mode to use: readonly or vendor. See 'go help modules' for more. -pkgdir dir install and load all packages from dir instead of the usual locations. @@ -398,10 +398,10 @@ func libname(args []string, pkgs []*load.Package) (string, error) { arg = bp.ImportPath } } - appendName(strings.Replace(arg, "/", "-", -1)) + appendName(strings.ReplaceAll(arg, "/", "-")) } else { for _, pkg := range pkgs { - appendName(strings.Replace(pkg.ImportPath, "/", "-", -1)) + appendName(strings.ReplaceAll(pkg.ImportPath, "/", "-")) } } } else if haveNonMeta { // have both meta package and a non-meta one diff --git a/src/cmd/go/internal/work/buildid.go b/src/cmd/go/internal/work/buildid.go index f6b79711f9..8b97e8b75b 100644 --- a/src/cmd/go/internal/work/buildid.go +++ b/src/cmd/go/internal/work/buildid.go @@ -348,8 +348,12 @@ func (b *Builder) gccgoBuildIDELFFile(a *Action) (string, error) { } fmt.Fprintf(&buf, "\n") if cfg.Goos != "solaris" { - fmt.Fprintf(&buf, "\t"+`.section .note.GNU-stack,"",@progbits`+"\n") - fmt.Fprintf(&buf, "\t"+`.section .note.GNU-split-stack,"",@progbits`+"\n") + secType := "@progbits" + if cfg.Goarch == "arm" { + secType = "%progbits" + } + fmt.Fprintf(&buf, "\t"+`.section .note.GNU-stack,"",%s`+"\n", secType) + fmt.Fprintf(&buf, "\t"+`.section .note.GNU-split-stack,"",%s`+"\n", secType) } if cfg.BuildN || cfg.BuildX { diff --git a/src/cmd/go/internal/work/exec.go b/src/cmd/go/internal/work/exec.go index 01414a3d57..158f5f3b17 100644 --- a/src/cmd/go/internal/work/exec.go +++ b/src/cmd/go/internal/work/exec.go @@ -1705,14 +1705,14 @@ func (b *Builder) fmtcmd(dir string, format string, args ...interface{}) string if dir[len(dir)-1] == filepath.Separator { dot += string(filepath.Separator) } - cmd = strings.Replace(" "+cmd, " "+dir, dot, -1)[1:] + cmd = strings.ReplaceAll(" "+cmd, " "+dir, dot)[1:] if b.scriptDir != dir { b.scriptDir = dir cmd = "cd " + dir + "\n" + cmd } } if b.WorkDir != "" { - cmd = strings.Replace(cmd, b.WorkDir, "$WORK", -1) + cmd = strings.ReplaceAll(cmd, b.WorkDir, "$WORK") } return cmd } @@ -1754,10 +1754,10 @@ func (b *Builder) showOutput(a *Action, dir, desc, out string) { prefix := "# " + desc suffix := "\n" + out if reldir := base.ShortPath(dir); reldir != dir { - suffix = strings.Replace(suffix, " "+dir, " "+reldir, -1) - suffix = strings.Replace(suffix, "\n"+dir, "\n"+reldir, -1) + suffix = strings.ReplaceAll(suffix, " "+dir, " "+reldir) + suffix = strings.ReplaceAll(suffix, "\n"+dir, "\n"+reldir) } - suffix = strings.Replace(suffix, " "+b.WorkDir, " $WORK", -1) + suffix = strings.ReplaceAll(suffix, " "+b.WorkDir, " $WORK") if a != nil && a.output != nil { a.output = append(a.output, prefix...) diff --git a/src/cmd/go/internal/work/security.go b/src/cmd/go/internal/work/security.go index d5d126123a..1a401b8981 100644 --- a/src/cmd/go/internal/work/security.go +++ b/src/cmd/go/internal/work/security.go @@ -89,7 +89,9 @@ var validCompilerFlags = []*regexp.Regexp{ re(`-m32`), re(`-m64`), re(`-m(abi|arch|cpu|fpu|tune)=([^@\-].*)`), + re(`-m(no-)?v?aes`), re(`-marm`), + re(`-m(no-)?avx[0-9a-z]*`), re(`-mfloat-abi=([^@\-].*)`), re(`-mfpmath=[0-9a-z,+]*`), re(`-m(no-)?avx[0-9a-z.]*`), @@ -100,6 +102,7 @@ var validCompilerFlags = []*regexp.Regexp{ re(`-miphoneos-version-min=(.+)`), re(`-mnop-fun-dllimport`), re(`-m(no-)?sse[0-9.]*`), + re(`-m(no-)?ssse3`), re(`-mthumb(-interwork)?`), re(`-mthreads`), re(`-mwindows`), @@ -170,6 +173,7 @@ var validLinkerFlags = []*regexp.Regexp{ re(`-Wl,-e[=,][a-zA-Z0-9]*`), re(`-Wl,--enable-new-dtags`), re(`-Wl,--end-group`), + re(`-Wl,--(no-)?export-dynamic`), re(`-Wl,-framework,[^,@\-][^,]+`), re(`-Wl,-headerpad_max_install_names`), re(`-Wl,--no-undefined`), diff --git a/src/cmd/go/main.go b/src/cmd/go/main.go index 31c554e715..d6934ce5e9 100644 --- a/src/cmd/go/main.go +++ b/src/cmd/go/main.go @@ -93,6 +93,15 @@ func main() { *get.CmdGet = *modget.CmdGet } + if args[0] == "get" || args[0] == "help" { + // Replace get with module-aware get if appropriate. + // Note that if MustUseModules is true, this happened already above, + // but no harm in doing it again. + if modload.Init(); modload.Enabled() { + *get.CmdGet = *modget.CmdGet + } + } + cfg.CmdName = args[0] // for error messages if args[0] == "help" { help.Help(os.Stdout, args[1:]) @@ -161,15 +170,6 @@ func main() { os.Exit(2) } - if args[0] == "get" { - // Replace get with module-aware get if appropriate. - // Note that if MustUseModules is true, this happened already above, - // but no harm in doing it again. - if modload.Init(); modload.Enabled() { - *get.CmdGet = *modget.CmdGet - } - } - // Set environment (GOOS, GOARCH, etc) explicitly. // In theory all the commands we invoke should have // the same default computation of these as we do, diff --git a/src/cmd/go/proxy_test.go b/src/cmd/go/proxy_test.go index 212e5aa08f..97fc4b0e80 100644 --- a/src/cmd/go/proxy_test.go +++ b/src/cmd/go/proxy_test.go @@ -78,7 +78,7 @@ func readModList() { if i < 0 { continue } - encPath := strings.Replace(name[:i], "_", "/", -1) + encPath := strings.ReplaceAll(name[:i], "_", "/") path, err := module.DecodePath(encPath) if err != nil { fmt.Fprintf(os.Stderr, "go proxy_test: %v\n", err) @@ -256,7 +256,7 @@ func readArchive(path, vers string) *txtar.Archive { return nil } - prefix := strings.Replace(enc, "/", "_", -1) + prefix := strings.ReplaceAll(enc, "/", "_") name := filepath.Join(cmdGoDir, "testdata/mod", prefix+"_"+encVers+".txt") a := archiveCache.Do(name, func() interface{} { a, err := txtar.ParseFile(name) diff --git a/src/cmd/go/script_test.go b/src/cmd/go/script_test.go index 7c083a87b9..31c6ede2a5 100644 --- a/src/cmd/go/script_test.go +++ b/src/cmd/go/script_test.go @@ -329,7 +329,7 @@ func (ts *testScript) cmdAddcrlf(neg bool, args []string) { file = ts.mkabs(file) data, err := ioutil.ReadFile(file) ts.check(err) - ts.check(ioutil.WriteFile(file, bytes.Replace(data, []byte("\n"), []byte("\r\n"), -1), 0666)) + ts.check(ioutil.WriteFile(file, bytes.ReplaceAll(data, []byte("\n"), []byte("\r\n")), 0666)) } } @@ -630,7 +630,7 @@ func scriptMatch(ts *testScript, neg bool, args []string, text, name string) { } // Matching against workdir would be misleading. - text = strings.Replace(text, ts.workdir, "$WORK", -1) + text = strings.ReplaceAll(text, ts.workdir, "$WORK") if neg { if re.MatchString(text) { @@ -691,7 +691,7 @@ func (ts *testScript) cmdSymlink(neg bool, args []string) { // abbrev abbreviates the actual work directory in the string s to the literal string "$WORK". func (ts *testScript) abbrev(s string) string { - s = strings.Replace(s, ts.workdir, "$WORK", -1) + s = strings.ReplaceAll(s, ts.workdir, "$WORK") if *testWork { // Expose actual $WORK value in environment dump on first line of work script, // so that the user can find out what directory -testwork left behind. @@ -885,17 +885,17 @@ var diffTests = []struct { func TestDiff(t *testing.T) { for _, tt := range diffTests { // Turn spaces into \n. - text1 := strings.Replace(tt.text1, " ", "\n", -1) + text1 := strings.ReplaceAll(tt.text1, " ", "\n") if text1 != "" { text1 += "\n" } - text2 := strings.Replace(tt.text2, " ", "\n", -1) + text2 := strings.ReplaceAll(tt.text2, " ", "\n") if text2 != "" { text2 += "\n" } out := diff(text1, text2) // Cut final \n, cut spaces, turn remaining \n into spaces. - out = strings.Replace(strings.Replace(strings.TrimSuffix(out, "\n"), " ", "", -1), "\n", " ", -1) + out = strings.ReplaceAll(strings.ReplaceAll(strings.TrimSuffix(out, "\n"), " ", ""), "\n", " ") if out != tt.diff { t.Errorf("diff(%q, %q) = %q, want %q", text1, text2, out, tt.diff) } diff --git a/src/cmd/go/testdata/addmod.go b/src/cmd/go/testdata/addmod.go index 19850af0f3..8bb6056a54 100644 --- a/src/cmd/go/testdata/addmod.go +++ b/src/cmd/go/testdata/addmod.go @@ -142,7 +142,7 @@ func main() { } data := txtar.Format(a) - target := filepath.Join("mod", strings.Replace(path, "/", "_", -1)+"_"+vers+".txt") + target := filepath.Join("mod", strings.ReplaceAll(path, "/", "_")+"_"+vers+".txt") if err := ioutil.WriteFile(target, data, 0666); err != nil { log.Printf("%s: %v", arg, err) exitCode = 1 diff --git a/src/cmd/go/testdata/script/help.txt b/src/cmd/go/testdata/script/help.txt index 939da30283..656e680100 100644 --- a/src/cmd/go/testdata/script/help.txt +++ b/src/cmd/go/testdata/script/help.txt @@ -34,3 +34,8 @@ stderr 'Run ''go help mod'' for usage.' ! go vet -h stderr 'usage: go vet' stderr 'Run ''go help vet'' for details' + +# go help get shows usage for get +go help get +stdout 'usage: go get' +stdout 'get when using GOPATH'
\ No newline at end of file diff --git a/src/cmd/go/testdata/script/list_bad_import.txt b/src/cmd/go/testdata/script/list_bad_import.txt index ba66b0937f..3d9cac0d5f 100644 --- a/src/cmd/go/testdata/script/list_bad_import.txt +++ b/src/cmd/go/testdata/script/list_bad_import.txt @@ -47,7 +47,7 @@ stdout error stdout incomplete -# The pattern "all" should match only packages that acutally exist, +# The pattern "all" should match only packages that actually exist, # ignoring those whose existence is merely implied by imports. go list -e -f '{{.ImportPath}}' all stdout example.com/direct diff --git a/src/cmd/go/testdata/script/mod_clean_cache.txt b/src/cmd/go/testdata/script/mod_clean_cache.txt new file mode 100644 index 0000000000..66a0e9ea7e --- /dev/null +++ b/src/cmd/go/testdata/script/mod_clean_cache.txt @@ -0,0 +1,23 @@ +env GO111MODULE=on + +go mod download rsc.io/quote@v1.5.0 +exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.info +exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.mod +exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.zip + +go clean -modcache -n +stdout '^rm -rf .*pkg.mod$' +exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.info +exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.mod +exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.zip + +go clean -modcache +! exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.info +! exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.mod +! exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.0.zip + +-- go.mod -- +module m + +-- m.go -- +package m
\ No newline at end of file diff --git a/src/cmd/go/testdata/script/mod_help.txt b/src/cmd/go/testdata/script/mod_help.txt new file mode 100644 index 0000000000..b5cd30c521 --- /dev/null +++ b/src/cmd/go/testdata/script/mod_help.txt @@ -0,0 +1,6 @@ +env GO111MODULE=on + +# go help get shows usage for get +go help get +stdout 'usage: go get' +stdout 'get using modules to manage source'
\ No newline at end of file diff --git a/src/cmd/go/testdata/script/mod_list_bad_import.txt b/src/cmd/go/testdata/script/mod_list_bad_import.txt index 258eb6a567..8a66e0b72a 100644 --- a/src/cmd/go/testdata/script/mod_list_bad_import.txt +++ b/src/cmd/go/testdata/script/mod_list_bad_import.txt @@ -47,7 +47,7 @@ stdout error stdout incomplete -# The pattern "all" should match only packages that acutally exist, +# The pattern "all" should match only packages that actually exist, # ignoring those whose existence is merely implied by imports. go list -e -f '{{.ImportPath}} {{.Error}}' all stdout example.com/direct diff --git a/src/cmd/go/testdata/script/mod_string_alias.txt b/src/cmd/go/testdata/script/mod_string_alias.txt new file mode 100644 index 0000000000..5c3d4287cc --- /dev/null +++ b/src/cmd/go/testdata/script/mod_string_alias.txt @@ -0,0 +1,14 @@ +[short] skip + +env GO111MODULE=on + +go mod init golang.org/issue/27584 + +go build . + +-- main.go -- +package main + +type string = []int + +func main() {} diff --git a/src/cmd/go/testdata/script/mod_test.txt b/src/cmd/go/testdata/script/mod_test.txt index caeb25ada8..af4fd76d70 100644 --- a/src/cmd/go/testdata/script/mod_test.txt +++ b/src/cmd/go/testdata/script/mod_test.txt @@ -1,5 +1,8 @@ env GO111MODULE=on +# TODO(bcmills): Convert the 'go test' calls below to 'go list -test' once 'go +# list' is more sensitive to package loading errors. + # A test in the module's root package should work. cd a/ cp go.mod.empty go.mod @@ -48,6 +51,10 @@ cd ../d_test go test stdout PASS +cd ../e +go test +stdout PASS + -- a/go.mod.empty -- module example.com/user/a diff --git a/src/cmd/go/vendor_test.go b/src/cmd/go/vendor_test.go index 22aa643b00..c302d7e9b5 100644 --- a/src/cmd/go/vendor_test.go +++ b/src/cmd/go/vendor_test.go @@ -37,7 +37,7 @@ func TestVendorImports(t *testing.T) { vend/x/vendor/p/p [notfound] vend/x/vendor/r [] ` - want = strings.Replace(want+"\t", "\n\t\t", "\n", -1) + want = strings.ReplaceAll(want+"\t", "\n\t\t", "\n") want = strings.TrimPrefix(want, "\n") have := tg.stdout.String() diff --git a/src/cmd/gofmt/gofmt_test.go b/src/cmd/gofmt/gofmt_test.go index 16b653b646..3008365cd2 100644 --- a/src/cmd/gofmt/gofmt_test.go +++ b/src/cmd/gofmt/gofmt_test.go @@ -200,7 +200,7 @@ func TestDiff(t *testing.T) { } if runtime.GOOS == "windows" { - b = bytes.Replace(b, []byte{'\r', '\n'}, []byte{'\n'}, -1) + b = bytes.ReplaceAll(b, []byte{'\r', '\n'}, []byte{'\n'}) } bs := bytes.SplitN(b, []byte{'\n'}, 3) diff --git a/src/cmd/internal/dwarf/dwarf.go b/src/cmd/internal/dwarf/dwarf.go index 96fb2b765b..355091feda 100644 --- a/src/cmd/internal/dwarf/dwarf.go +++ b/src/cmd/internal/dwarf/dwarf.go @@ -304,6 +304,7 @@ const ( const ( DW_ABRV_NULL = iota DW_ABRV_COMPUNIT + DW_ABRV_COMPUNIT_TEXTLESS DW_ABRV_FUNCTION DW_ABRV_FUNCTION_ABSTRACT DW_ABRV_FUNCTION_CONCRETE @@ -368,6 +369,18 @@ var abbrevs = [DW_NABRV]dwAbbrev{ }, }, + /* COMPUNIT_TEXTLESS */ + { + DW_TAG_compile_unit, + DW_CHILDREN_yes, + []dwAttrForm{ + {DW_AT_name, DW_FORM_string}, + {DW_AT_language, DW_FORM_data1}, + {DW_AT_comp_dir, DW_FORM_string}, + {DW_AT_producer, DW_FORM_string}, + }, + }, + /* FUNCTION */ { DW_TAG_subprogram, diff --git a/src/cmd/internal/goobj/read.go b/src/cmd/internal/goobj/read.go index e39180cad6..2d618eefa5 100644 --- a/src/cmd/internal/goobj/read.go +++ b/src/cmd/internal/goobj/read.go @@ -293,7 +293,7 @@ func (r *objReader) readRef() { // In a symbol name in an object file, "". denotes the // prefix for the package in which the object file has been found. // Expand it. - name = strings.Replace(name, `"".`, r.pkgprefix, -1) + name = strings.ReplaceAll(name, `"".`, r.pkgprefix) // An individual object file only records version 0 (extern) or 1 (static). // To make static symbols unique across all files being read, we diff --git a/src/cmd/internal/obj/arm/asm5.go b/src/cmd/internal/obj/arm/asm5.go index 3427ea9161..dd6d9265c4 100644 --- a/src/cmd/internal/obj/arm/asm5.go +++ b/src/cmd/internal/obj/arm/asm5.go @@ -2007,7 +2007,7 @@ func (c *ctxt5) asmout(p *obj.Prog, o *Optab, out []uint32) { o2 = c.oprrr(p, p.As, int(p.Scond)) o2 |= REGTMP & 15 r := int(p.Reg) - if p.As == AMOVW || p.As == AMVN { + if p.As == AMVN { r = 0 } else if r == 0 { r = int(p.To.Reg) diff --git a/src/cmd/internal/obj/arm64/asm7.go b/src/cmd/internal/obj/arm64/asm7.go index 7507976257..46fdcdcf7d 100644 --- a/src/cmd/internal/obj/arm64/asm7.go +++ b/src/cmd/internal/obj/arm64/asm7.go @@ -1085,6 +1085,23 @@ func (c *ctxt7) regoff(a *obj.Addr) uint32 { return uint32(c.instoffset) } +func isSTLXRop(op obj.As) bool { + switch op { + case ASTLXR, ASTLXRW, ASTLXRB, ASTLXRH, + ASTXR, ASTXRW, ASTXRB, ASTXRH: + return true + } + return false +} + +func isSTXPop(op obj.As) bool { + switch op { + case ASTXP, ASTLXP, ASTXPW, ASTLXPW: + return true + } + return false +} + func isRegShiftOrExt(a *obj.Addr) bool { return (a.Index-obj.RBaseARM64)®_EXT != 0 || (a.Index-obj.RBaseARM64)®_LSL != 0 } @@ -1409,6 +1426,10 @@ func (c *ctxt7) aclass(a *obj.Addr) int { return C_LIST case obj.TYPE_MEM: + // The base register should be an integer register. + if int16(REG_F0) <= a.Reg && a.Reg <= int16(REG_V31) { + break + } switch a.Name { case obj.NAME_EXTERN, obj.NAME_STATIC: if a.Sym == nil { @@ -2502,6 +2523,17 @@ func SYSARG4(op1 int, Cn int, Cm int, op2 int) int { return SYSARG5(0, op1, Cn, Cm, op2) } +// checkUnpredictable checks if the sourse and transfer registers are the same register. +// ARM64 manual says it is "constrained unpredictable" if the src and dst registers of STP/LDP are same. +func (c *ctxt7) checkUnpredictable(p *obj.Prog, isload bool, wback bool, rn int16, rt1 int16, rt2 int16) { + if wback && rn != REGSP && (rn == rt1 || rn == rt2) { + c.ctxt.Diag("constrained unpredictable behavior: %v", p) + } + if isload && rt1 == rt2 { + c.ctxt.Diag("constrained unpredictable behavior: %v", p) + } +} + /* checkindex checks if index >= 0 && index <= maxindex */ func (c *ctxt7) checkindex(p *obj.Prog, index, maxindex int) { if index < 0 || index > maxindex { @@ -2940,6 +2972,10 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) { } case 22: /* movT (R)O!,R; movT O(R)!, R -> ldrT */ + if p.From.Reg != REGSP && p.From.Reg == p.To.Reg { + c.ctxt.Diag("constrained unpredictable behavior: %v", p) + } + v := int32(p.From.Offset) if v < -256 || v > 255 { @@ -2954,6 +2990,10 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) { o1 |= ((uint32(v) & 0x1FF) << 12) | (uint32(p.From.Reg&31) << 5) | uint32(p.To.Reg&31) case 23: /* movT R,(R)O!; movT O(R)!, R -> strT */ + if p.To.Reg != REGSP && p.From.Reg == p.To.Reg { + c.ctxt.Diag("constrained unpredictable behavior: %v", p) + } + v := int32(p.To.Offset) if v < -256 || v > 255 { @@ -3551,6 +3591,9 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) { o1 |= 0x1F << 16 o1 |= uint32(p.From.Reg&31) << 5 if p.As == ALDXP || p.As == ALDXPW || p.As == ALDAXP || p.As == ALDAXPW { + if int(p.To.Reg) == int(p.To.Offset) { + c.ctxt.Diag("constrained unpredictable behavior: %v", p) + } o1 |= uint32(p.To.Offset&31) << 10 } else { o1 |= 0x1F << 10 @@ -3558,6 +3601,19 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) { o1 |= uint32(p.To.Reg & 31) case 59: /* stxr/stlxr/stxp/stlxp */ + s := p.RegTo2 + n := p.To.Reg + t := p.From.Reg + if isSTLXRop(p.As) { + if s == t || (s == n && n != REGSP) { + c.ctxt.Diag("constrained unpredictable behavior: %v", p) + } + } else if isSTXPop(p.As) { + t2 := int16(p.From.Offset) + if (s == t || s == t2) || (s == n && n != REGSP) { + c.ctxt.Diag("constrained unpredictable behavior: %v", p) + } + } o1 = c.opstore(p, p.As) if p.RegTo2 != obj.REG_NONE { @@ -3565,7 +3621,7 @@ func (c *ctxt7) asmout(p *obj.Prog, o *Optab, out []uint32) { } else { o1 |= 0x1F << 16 } - if p.As == ASTXP || p.As == ASTXPW || p.As == ASTLXP || p.As == ASTLXPW { + if isSTXPop(p.As) { o1 |= uint32(p.From.Offset&31) << 10 } o1 |= uint32(p.To.Reg&31)<<5 | uint32(p.From.Reg&31) @@ -6177,6 +6233,20 @@ func (c *ctxt7) opextr(p *obj.Prog, a obj.As, v int32, rn int, rm int, rt int) u /* genrate instruction encoding for LDP/LDPW/LDPSW/STP/STPW */ func (c *ctxt7) opldpstp(p *obj.Prog, o *Optab, vo int32, rbase, rl, rh, ldp uint32) uint32 { + wback := false + if o.scond == C_XPOST || o.scond == C_XPRE { + wback = true + } + switch p.As { + case ALDP, ALDPW, ALDPSW: + c.checkUnpredictable(p, true, wback, p.From.Reg, p.To.Reg, int16(p.To.Offset)) + case ASTP, ASTPW: + if wback == true { + c.checkUnpredictable(p, false, true, p.To.Reg, p.From.Reg, int16(p.From.Offset)) + } + case AFLDPD, AFLDPS: + c.checkUnpredictable(p, true, false, p.From.Reg, p.To.Reg, int16(p.To.Offset)) + } var ret uint32 // check offset switch p.As { diff --git a/src/cmd/internal/obj/link.go b/src/cmd/internal/obj/link.go index 132f7836ef..354bda5e48 100644 --- a/src/cmd/internal/obj/link.go +++ b/src/cmd/internal/obj/link.go @@ -402,9 +402,10 @@ type FuncInfo struct { dwarfAbsFnSym *LSym dwarfIsStmtSym *LSym - GCArgs LSym - GCLocals LSym - GCRegs LSym + GCArgs LSym + GCLocals LSym + GCRegs LSym + StackObjects *LSym } // Attribute is a set of symbol attributes. diff --git a/src/cmd/internal/objabi/funcdata.go b/src/cmd/internal/objabi/funcdata.go index a7827125bf..231d11b185 100644 --- a/src/cmd/internal/objabi/funcdata.go +++ b/src/cmd/internal/objabi/funcdata.go @@ -18,6 +18,7 @@ const ( FUNCDATA_LocalsPointerMaps = 1 FUNCDATA_InlTree = 2 FUNCDATA_RegPointerMaps = 3 + FUNCDATA_StackObjects = 4 // ArgsSizeUnknown is set in Func.argsize to mark all functions // whose argument size is unknown (C vararg functions, and diff --git a/src/cmd/internal/objabi/funcid.go b/src/cmd/internal/objabi/funcid.go index 15a63ab8b3..92799107da 100644 --- a/src/cmd/internal/objabi/funcid.go +++ b/src/cmd/internal/objabi/funcid.go @@ -9,7 +9,7 @@ package objabi // Note that in some situations involving plugins, there may be multiple // copies of a particular special runtime function. // Note: this list must match the list in runtime/symtab.go. -type FuncID uint32 +type FuncID uint8 const ( FuncID_normal FuncID = iota // not a special function diff --git a/src/cmd/internal/objabi/head.go b/src/cmd/internal/objabi/head.go index 23c7b62daf..db2221d6b1 100644 --- a/src/cmd/internal/objabi/head.go +++ b/src/cmd/internal/objabi/head.go @@ -48,10 +48,13 @@ const ( Hplan9 Hsolaris Hwindows + Haix ) func (h *HeadType) Set(s string) error { switch s { + case "aix": + *h = Haix case "darwin": *h = Hdarwin case "dragonfly": @@ -82,6 +85,8 @@ func (h *HeadType) Set(s string) error { func (h *HeadType) String() string { switch *h { + case Haix: + return "aix" case Hdarwin: return "darwin" case Hdragonfly: diff --git a/src/cmd/link/dwarf_test.go b/src/cmd/link/dwarf_test.go index ff11689bbc..2c01456f6b 100644 --- a/src/cmd/link/dwarf_test.go +++ b/src/cmd/link/dwarf_test.go @@ -122,6 +122,9 @@ func testDWARF(t *testing.T, buildmode string, expectDWARF bool, env ...string) r.SkipChildren() continue } + if cu.Val(dwarf.AttrStmtList) == nil { + continue + } lr, err := d.LineReader(cu) if err != nil { t.Fatal(err) diff --git a/src/cmd/link/internal/ld/dwarf.go b/src/cmd/link/internal/ld/dwarf.go index 959fc8290c..743f4cedd4 100644 --- a/src/cmd/link/internal/ld/dwarf.go +++ b/src/cmd/link/internal/ld/dwarf.go @@ -5,7 +5,7 @@ // TODO/NICETOHAVE: // - eliminate DW_CLS_ if not used // - package info in compilation units -// - assign global variables and types to their packages +// - assign types to their packages // - gdb uses c syntax, meaning clumsy quoting is needed for go identifiers. eg // ptype struct '[]uint8' and qualifiers need to be quoted away // - file:line info for variables @@ -106,15 +106,8 @@ func writeabbrev(ctxt *Link) *sym.Symbol { return s } -/* - * Root DIEs for compilation units, types and global variables. - */ -var dwroot dwarf.DWDie - var dwtypes dwarf.DWDie -var dwglobals dwarf.DWDie - func newattr(die *dwarf.DWDie, attr uint16, cls int, value int64, data interface{}) *dwarf.DWAttr { a := new(dwarf.DWAttr) a.Link = die.Attr @@ -340,19 +333,19 @@ func lookupOrDiag(ctxt *Link, n string) *sym.Symbol { return s } -func dotypedef(ctxt *Link, parent *dwarf.DWDie, name string, def *dwarf.DWDie) { +func dotypedef(ctxt *Link, parent *dwarf.DWDie, name string, def *dwarf.DWDie) *dwarf.DWDie { // Only emit typedefs for real names. if strings.HasPrefix(name, "map[") { - return + return nil } if strings.HasPrefix(name, "struct {") { - return + return nil } if strings.HasPrefix(name, "chan ") { - return + return nil } if name[0] == '[' || name[0] == '*' { - return + return nil } if def == nil { Errorf(nil, "dwarf: bad def in dotypedef") @@ -370,6 +363,8 @@ func dotypedef(ctxt *Link, parent *dwarf.DWDie, name string, def *dwarf.DWDie) { die := newdie(ctxt, parent, dwarf.DW_ABRV_TYPEDECL, name, 0) newrefattr(die, dwarf.DW_AT_type, s) + + return die } // Define gotype, for composite ones recurse into constituents. @@ -399,7 +394,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { kind := decodetypeKind(ctxt.Arch, gotype) bytesize := decodetypeSize(ctxt.Arch, gotype) - var die *dwarf.DWDie + var die, typedefdie *dwarf.DWDie switch kind { case objabi.KindBool: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_BASETYPE, name, 0) @@ -439,7 +434,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindArray: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_ARRAYTYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) s := decodetypeArrayElem(ctxt.Arch, gotype) newrefattr(die, dwarf.DW_AT_type, defgotype(ctxt, s)) @@ -461,7 +456,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindFunc: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_FUNCTYPE, name, 0) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) nfields := decodetypeFuncInCount(ctxt.Arch, gotype) for i := 0; i < nfields; i++ { s := decodetypeFuncInType(ctxt.Arch, gotype, i) @@ -481,7 +476,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindInterface: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_IFACETYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) nfields := int(decodetypeIfaceMethodCount(ctxt.Arch, gotype)) var s *sym.Symbol if nfields == 0 { @@ -503,13 +498,13 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindPtr: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_PTRTYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) s := decodetypePtrElem(ctxt.Arch, gotype) newrefattr(die, dwarf.DW_AT_type, defgotype(ctxt, s)) case objabi.KindSlice: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_SLICETYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) s := decodetypeArrayElem(ctxt.Arch, gotype) elem := defgotype(ctxt, s) @@ -521,7 +516,7 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { case objabi.KindStruct: die = newdie(ctxt, &dwtypes, dwarf.DW_ABRV_STRUCTTYPE, name, 0) - dotypedef(ctxt, &dwtypes, name, die) + typedefdie = dotypedef(ctxt, &dwtypes, name, die) newattr(die, dwarf.DW_AT_byte_size, dwarf.DW_CLS_CONSTANT, bytesize, 0) nfields := decodetypeStructFieldCount(ctxt.Arch, gotype) for i := 0; i < nfields; i++ { @@ -557,6 +552,9 @@ func newtype(ctxt *Link, gotype *sym.Symbol) *dwarf.DWDie { prototypedies[gotype.Name] = die } + if typedefdie != nil { + return typedefdie + } return die } @@ -830,7 +828,11 @@ func synthesizechantypes(ctxt *Link, die *dwarf.DWDie) { } func dwarfDefineGlobal(ctxt *Link, s *sym.Symbol, str string, v int64, gotype *sym.Symbol) { - dv := newdie(ctxt, &dwglobals, dwarf.DW_ABRV_VARIABLE, str, int(s.Version)) + lib := s.Lib + if lib == nil { + lib = ctxt.LibraryByPkg["runtime"] + } + dv := newdie(ctxt, ctxt.compUnitByPackage[lib].dwinfo, dwarf.DW_ABRV_VARIABLE, str, int(s.Version)) newabslocexprattr(dv, v, s) if s.Version == 0 { newattr(dv, dwarf.DW_AT_external, dwarf.DW_CLS_FLAG, 1, 0) @@ -905,10 +907,11 @@ func calcCompUnitRanges(ctxt *Link) { } } -func movetomodule(parent *dwarf.DWDie) { - die := dwroot.Child.Child +func movetomodule(ctxt *Link, parent *dwarf.DWDie) { + runtimelib := ctxt.LibraryByPkg["runtime"] + die := ctxt.compUnitByPackage[runtimelib].dwinfo.Child if die == nil { - dwroot.Child.Child = parent.Child + ctxt.compUnitByPackage[runtimelib].dwinfo.Child = parent.Child return } for die.Link != nil { @@ -1062,7 +1065,7 @@ func importInfoSymbol(ctxt *Link, dsym *sym.Symbol) { } } -func writelines(ctxt *Link, unit *compilationUnit, ls *sym.Symbol) (dwinfo *dwarf.DWDie) { +func writelines(ctxt *Link, unit *compilationUnit, ls *sym.Symbol) { var dwarfctxt dwarf.Context = dwctxt{ctxt} is_stmt := uint8(1) // initially = recommended default_is_stmt = 1, tracks is_stmt toggles. @@ -1071,29 +1074,7 @@ func writelines(ctxt *Link, unit *compilationUnit, ls *sym.Symbol) (dwinfo *dwar headerstart := int64(-1) headerend := int64(-1) - lang := dwarf.DW_LANG_Go - - dwinfo = newdie(ctxt, &dwroot, dwarf.DW_ABRV_COMPUNIT, unit.lib.Pkg, 0) - newattr(dwinfo, dwarf.DW_AT_language, dwarf.DW_CLS_CONSTANT, int64(lang), 0) - newattr(dwinfo, dwarf.DW_AT_stmt_list, dwarf.DW_CLS_PTR, ls.Size, ls) - // OS X linker requires compilation dir or absolute path in comp unit name to output debug info. - compDir := getCompilationDir() - // TODO: Make this be the actual compilation directory, not - // the linker directory. If we move CU construction into the - // compiler, this should happen naturally. - newattr(dwinfo, dwarf.DW_AT_comp_dir, dwarf.DW_CLS_STRING, int64(len(compDir)), compDir) - producerExtra := ctxt.Syms.Lookup(dwarf.CUInfoPrefix+"producer."+unit.lib.Pkg, 0) - producer := "Go cmd/compile " + objabi.Version - if len(producerExtra.P) > 0 { - // We put a semicolon before the flags to clearly - // separate them from the version, which can be long - // and have lots of weird things in it in development - // versions. We promise not to put a semicolon in the - // version, so it should be safe for readers to scan - // forward to the semicolon. - producer += "; " + string(producerExtra.P) - } - newattr(dwinfo, dwarf.DW_AT_producer, dwarf.DW_CLS_STRING, int64(len(producer)), producer) + newattr(unit.dwinfo, dwarf.DW_AT_stmt_list, dwarf.DW_CLS_PTR, ls.Size, ls) // Write .debug_line Line Number Program Header (sec 6.2.4) // Fields marked with (*) must be changed for 64-bit dwarf @@ -1295,8 +1276,6 @@ func writelines(ctxt *Link, unit *compilationUnit, ls *sym.Symbol) (dwinfo *dwar } } } - - return dwinfo } // writepcranges generates the DW_AT_ranges table for compilation unit cu. @@ -1463,15 +1442,13 @@ func writeinfo(ctxt *Link, syms []*sym.Symbol, units []*compilationUnit, abbrevs var dwarfctxt dwarf.Context = dwctxt{ctxt} - // Re-index per-package information by its CU die. - unitByDIE := make(map[*dwarf.DWDie]*compilationUnit) for _, u := range units { - unitByDIE[u.dwinfo] = u - } - - for compunit := dwroot.Child; compunit != nil; compunit = compunit.Link { + compunit := u.dwinfo s := dtolsym(compunit.Sym) - u := unitByDIE[compunit] + + if len(u.lib.Textp) == 0 && u.dwinfo.Child == nil { + continue + } // Write .debug_info Compilation Unit Header (sec 7.5.1) // Fields marked with (*) must be changed for 64-bit dwarf @@ -1531,7 +1508,11 @@ func writepub(ctxt *Link, sname string, ispub func(*dwarf.DWDie) bool, syms []*s s.Type = sym.SDWARFSECT syms = append(syms, s) - for compunit := dwroot.Child; compunit != nil; compunit = compunit.Link { + for _, u := range ctxt.compUnits { + if len(u.lib.Textp) == 0 && u.dwinfo.Child == nil { + continue + } + compunit := u.dwinfo sectionstart := s.Size culength := uint32(getattr(compunit, dwarf.DW_AT_byte_size).Value) + 4 @@ -1666,13 +1647,10 @@ func dwarfGenerateDebugInfo(ctxt *Link) { defgotype(ctxt, lookupOrDiag(ctxt, typ)) } - // Create DIEs for global variables and the types they use. - genasmsym(ctxt, defdwsymb) + // fake root DIE for compile unit DIEs + var dwroot dwarf.DWDie for _, lib := range ctxt.Library { - if len(lib.Textp) == 0 { - continue - } unit := &compilationUnit{lib: lib} if s := ctxt.Syms.ROLookup(dwarf.ConstInfoPrefix+lib.Pkg, 0); s != nil { importInfoSymbol(ctxt, s) @@ -1681,6 +1659,31 @@ func dwarfGenerateDebugInfo(ctxt *Link) { ctxt.compUnits = append(ctxt.compUnits, unit) ctxt.compUnitByPackage[lib] = unit + unit.dwinfo = newdie(ctxt, &dwroot, dwarf.DW_ABRV_COMPUNIT, unit.lib.Pkg, 0) + newattr(unit.dwinfo, dwarf.DW_AT_language, dwarf.DW_CLS_CONSTANT, int64(dwarf.DW_LANG_Go), 0) + // OS X linker requires compilation dir or absolute path in comp unit name to output debug info. + compDir := getCompilationDir() + // TODO: Make this be the actual compilation directory, not + // the linker directory. If we move CU construction into the + // compiler, this should happen naturally. + newattr(unit.dwinfo, dwarf.DW_AT_comp_dir, dwarf.DW_CLS_STRING, int64(len(compDir)), compDir) + producerExtra := ctxt.Syms.Lookup(dwarf.CUInfoPrefix+"producer."+unit.lib.Pkg, 0) + producer := "Go cmd/compile " + objabi.Version + if len(producerExtra.P) > 0 { + // We put a semicolon before the flags to clearly + // separate them from the version, which can be long + // and have lots of weird things in it in development + // versions. We promise not to put a semicolon in the + // version, so it should be safe for readers to scan + // forward to the semicolon. + producer += "; " + string(producerExtra.P) + } + newattr(unit.dwinfo, dwarf.DW_AT_producer, dwarf.DW_CLS_STRING, int64(len(producer)), producer) + + if len(lib.Textp) == 0 { + unit.dwinfo.Abbrev = dwarf.DW_ABRV_COMPUNIT_TEXTLESS + } + // Scan all functions in this compilation unit, create DIEs for all // referenced types, create the file table for debug_line, find all // referenced abstract functions. @@ -1721,6 +1724,9 @@ func dwarfGenerateDebugInfo(ctxt *Link) { } } + // Create DIEs for global variables and the types they use. + genasmsym(ctxt, defdwsymb) + synthesizestringtypes(ctxt, dwtypes.Child) synthesizeslicetypes(ctxt, dwtypes.Child) synthesizemaptypes(ctxt, dwtypes.Child) @@ -1753,19 +1759,19 @@ func dwarfGenerateDebugSyms(ctxt *Link) { debugRanges.Attr |= sym.AttrReachable syms = append(syms, debugLine) for _, u := range ctxt.compUnits { - u.dwinfo = writelines(ctxt, u, debugLine) + reversetree(&u.dwinfo.Child) + if u.dwinfo.Abbrev == dwarf.DW_ABRV_COMPUNIT_TEXTLESS { + continue + } + writelines(ctxt, u, debugLine) writepcranges(ctxt, u.dwinfo, u.lib.Textp[0], u.pcs, debugRanges) } // newdie adds DIEs to the *beginning* of the parent's DIE list. // Now that we're done creating DIEs, reverse the trees so DIEs // appear in the order they were created. - reversetree(&dwroot.Child) reversetree(&dwtypes.Child) - reversetree(&dwglobals.Child) - - movetomodule(&dwtypes) - movetomodule(&dwglobals) + movetomodule(ctxt, &dwtypes) // Need to reorder symbols so sym.SDWARFINFO is after all sym.SDWARFSECT // (but we need to generate dies before writepub) @@ -2000,5 +2006,14 @@ func (v compilationUnitByStartPC) Len() int { return len(v) } func (v compilationUnitByStartPC) Swap(i, j int) { v[i], v[j] = v[j], v[i] } func (v compilationUnitByStartPC) Less(i, j int) bool { - return v[i].lib.Textp[0].Value < v[j].lib.Textp[0].Value + switch { + case len(v[i].lib.Textp) == 0 && len(v[j].lib.Textp) == 0: + return v[i].lib.Pkg < v[j].lib.Pkg + case len(v[i].lib.Textp) != 0 && len(v[j].lib.Textp) == 0: + return true + case len(v[i].lib.Textp) == 0 && len(v[j].lib.Textp) != 0: + return false + default: + return v[i].lib.Textp[0].Value < v[j].lib.Textp[0].Value + } } diff --git a/src/cmd/link/internal/ld/dwarf_test.go b/src/cmd/link/internal/ld/dwarf_test.go index 157bebbb41..5d2aadf589 100644 --- a/src/cmd/link/internal/ld/dwarf_test.go +++ b/src/cmd/link/internal/ld/dwarf_test.go @@ -948,3 +948,117 @@ func main() { t.Errorf("DWARF type offset was %#x+%#x, but test program said %#x", rtAttr.(uint64), types.Addr, addr) } } + +func TestIssue27614(t *testing.T) { + // Type references in debug_info should always use the DW_TAG_typedef_type + // for the type, when that's generated. + + testenv.MustHaveGoBuild(t) + + if runtime.GOOS == "plan9" { + t.Skip("skipping on plan9; no DWARF symbol table in executables") + } + + dir, err := ioutil.TempDir("", "go-build") + if err != nil { + t.Fatal(err) + } + defer os.RemoveAll(dir) + + const prog = `package main + +import "fmt" + +type astruct struct { + X int +} + +type bstruct struct { + X float32 +} + +var globalptr *astruct +var globalvar astruct +var bvar0, bvar1, bvar2 bstruct + +func main() { + fmt.Println(globalptr, globalvar, bvar0, bvar1, bvar2) +} +` + + f := gobuild(t, dir, prog, NoOpt) + + defer f.Close() + + data, err := f.DWARF() + if err != nil { + t.Fatal(err) + } + + rdr := data.Reader() + + var astructTypeDIE, bstructTypeDIE, ptrastructTypeDIE *dwarf.Entry + var globalptrDIE, globalvarDIE *dwarf.Entry + var bvarDIE [3]*dwarf.Entry + + for { + e, err := rdr.Next() + if err != nil { + t.Fatal(err) + } + if e == nil { + break + } + + name, _ := e.Val(dwarf.AttrName).(string) + + switch e.Tag { + case dwarf.TagTypedef: + switch name { + case "main.astruct": + astructTypeDIE = e + case "main.bstruct": + bstructTypeDIE = e + } + case dwarf.TagPointerType: + if name == "*main.astruct" { + ptrastructTypeDIE = e + } + case dwarf.TagVariable: + switch name { + case "main.globalptr": + globalptrDIE = e + case "main.globalvar": + globalvarDIE = e + default: + const bvarprefix = "main.bvar" + if strings.HasPrefix(name, bvarprefix) { + i, _ := strconv.Atoi(name[len(bvarprefix):]) + bvarDIE[i] = e + } + } + } + } + + typedieof := func(e *dwarf.Entry) dwarf.Offset { + return e.Val(dwarf.AttrType).(dwarf.Offset) + } + + if off := typedieof(ptrastructTypeDIE); off != astructTypeDIE.Offset { + t.Errorf("type attribute of *main.astruct references %#x, not main.astruct DIE at %#x\n", off, astructTypeDIE.Offset) + } + + if off := typedieof(globalptrDIE); off != ptrastructTypeDIE.Offset { + t.Errorf("type attribute of main.globalptr references %#x, not *main.astruct DIE at %#x\n", off, ptrastructTypeDIE.Offset) + } + + if off := typedieof(globalvarDIE); off != astructTypeDIE.Offset { + t.Errorf("type attribute of main.globalvar1 references %#x, not main.astruct DIE at %#x\n", off, astructTypeDIE.Offset) + } + + for i := range bvarDIE { + if off := typedieof(bvarDIE[i]); off != bstructTypeDIE.Offset { + t.Errorf("type attribute of main.bvar%d references %#x, not main.bstruct DIE at %#x\n", i, off, bstructTypeDIE.Offset) + } + } +} diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go index 919fa08f21..e911d7bf08 100644 --- a/src/cmd/link/internal/ld/lib.go +++ b/src/cmd/link/internal/ld/lib.go @@ -1380,9 +1380,58 @@ func linkerFlagSupported(linker, flag string) bool { } }) + flagsWithNextArgSkip := []string{ + "-F", + "-l", + "-L", + "-framework", + "-Wl,-framework", + "-Wl,-rpath", + "-Wl,-undefined", + } + flagsWithNextArgKeep := []string{ + "-arch", + "-isysroot", + "--sysroot", + "-target", + } + prefixesToKeep := []string{ + "-f", + "-m", + "-p", + "-Wl,", + "-arch", + "-isysroot", + "--sysroot", + "-target", + } + var flags []string - flags = append(flags, ldflag...) - flags = append(flags, strings.Fields(*flagExtldflags)...) + keep := false + skip := false + extldflags := strings.Fields(*flagExtldflags) + for _, f := range append(extldflags, ldflag...) { + if keep { + flags = append(flags, f) + keep = false + } else if skip { + skip = false + } else if f == "" || f[0] != '-' { + } else if contains(flagsWithNextArgSkip, f) { + skip = true + } else if contains(flagsWithNextArgKeep, f) { + flags = append(flags, f) + keep = true + } else { + for _, p := range prefixesToKeep { + if strings.HasPrefix(f, p) { + flags = append(flags, f) + break + } + } + } + } + flags = append(flags, flag, "trivial.c") cmd := exec.Command(linker, flags...) @@ -1758,26 +1807,6 @@ func addsection(arch *sys.Arch, seg *sym.Segment, name string, rwx int) *sym.Sec return sect } -func Le16(b []byte) uint16 { - return uint16(b[0]) | uint16(b[1])<<8 -} - -func Le32(b []byte) uint32 { - return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24 -} - -func Le64(b []byte) uint64 { - return uint64(Le32(b)) | uint64(Le32(b[4:]))<<32 -} - -func Be16(b []byte) uint16 { - return uint16(b[0])<<8 | uint16(b[1]) -} - -func Be32(b []byte) uint32 { - return uint32(b[0])<<24 | uint32(b[1])<<16 | uint32(b[2])<<8 | uint32(b[3]) -} - type chain struct { sym *sym.Symbol up *chain diff --git a/src/cmd/link/internal/ld/pcln.go b/src/cmd/link/internal/ld/pcln.go index 7b7f7068e7..24398fcc87 100644 --- a/src/cmd/link/internal/ld/pcln.go +++ b/src/cmd/link/internal/ld/pcln.go @@ -312,45 +312,19 @@ func (ctxt *Link) pclntab() { } off = int32(ftab.SetUint32(ctxt.Arch, int64(off), args)) - // funcID uint32 - funcID := objabi.FuncID_normal - switch s.Name { - case "runtime.main": - funcID = objabi.FuncID_runtime_main - case "runtime.goexit": - funcID = objabi.FuncID_goexit - case "runtime.jmpdefer": - funcID = objabi.FuncID_jmpdefer - case "runtime.mcall": - funcID = objabi.FuncID_mcall - case "runtime.morestack": - funcID = objabi.FuncID_morestack - case "runtime.mstart": - funcID = objabi.FuncID_mstart - case "runtime.rt0_go": - funcID = objabi.FuncID_rt0_go - case "runtime.asmcgocall": - funcID = objabi.FuncID_asmcgocall - case "runtime.sigpanic": - funcID = objabi.FuncID_sigpanic - case "runtime.runfinq": - funcID = objabi.FuncID_runfinq - case "runtime.gcBgMarkWorker": - funcID = objabi.FuncID_gcBgMarkWorker - case "runtime.systemstack_switch": - funcID = objabi.FuncID_systemstack_switch - case "runtime.systemstack": - funcID = objabi.FuncID_systemstack - case "runtime.cgocallback_gofunc": - funcID = objabi.FuncID_cgocallback_gofunc - case "runtime.gogo": - funcID = objabi.FuncID_gogo - case "runtime.externalthreadhandler": - funcID = objabi.FuncID_externalthreadhandler - case "runtime.debugCallV1": - funcID = objabi.FuncID_debugCallV1 + // deferreturn + deferreturn := uint32(0) + for _, r := range s.R { + if r.Sym != nil && r.Sym.Name == "runtime.deferreturn" && r.Add == 0 { + // Note: the relocation target is in the call instruction, but + // is not necessarily the whole instruction (for instance, on + // x86 the relocation applies to bytes [1:5] of the 5 byte call + // instruction). + deferreturn = uint32(r.Off) + break // only need one + } } - off = int32(ftab.SetUint32(ctxt.Arch, int64(off), uint32(funcID))) + off = int32(ftab.SetUint32(ctxt.Arch, int64(off), deferreturn)) if pcln != &pclntabZpcln { renumberfiles(ctxt, pcln.File, &pcln.Pcfile) @@ -396,7 +370,52 @@ func (ctxt *Link) pclntab() { off = addpctab(ctxt, ftab, off, &pcln.Pcfile) off = addpctab(ctxt, ftab, off, &pcln.Pcline) off = int32(ftab.SetUint32(ctxt.Arch, int64(off), uint32(len(pcln.Pcdata)))) - off = int32(ftab.SetUint32(ctxt.Arch, int64(off), uint32(len(pcln.Funcdata)))) + + // funcID uint8 + funcID := objabi.FuncID_normal + switch s.Name { + case "runtime.main": + funcID = objabi.FuncID_runtime_main + case "runtime.goexit": + funcID = objabi.FuncID_goexit + case "runtime.jmpdefer": + funcID = objabi.FuncID_jmpdefer + case "runtime.mcall": + funcID = objabi.FuncID_mcall + case "runtime.morestack": + funcID = objabi.FuncID_morestack + case "runtime.mstart": + funcID = objabi.FuncID_mstart + case "runtime.rt0_go": + funcID = objabi.FuncID_rt0_go + case "runtime.asmcgocall": + funcID = objabi.FuncID_asmcgocall + case "runtime.sigpanic": + funcID = objabi.FuncID_sigpanic + case "runtime.runfinq": + funcID = objabi.FuncID_runfinq + case "runtime.gcBgMarkWorker": + funcID = objabi.FuncID_gcBgMarkWorker + case "runtime.systemstack_switch": + funcID = objabi.FuncID_systemstack_switch + case "runtime.systemstack": + funcID = objabi.FuncID_systemstack + case "runtime.cgocallback_gofunc": + funcID = objabi.FuncID_cgocallback_gofunc + case "runtime.gogo": + funcID = objabi.FuncID_gogo + case "runtime.externalthreadhandler": + funcID = objabi.FuncID_externalthreadhandler + case "runtime.debugCallV1": + funcID = objabi.FuncID_debugCallV1 + } + off = int32(ftab.SetUint8(ctxt.Arch, int64(off), uint8(funcID))) + + // unused + off += 2 + + // nfuncdata must be the final entry. + off = int32(ftab.SetUint8(ctxt.Arch, int64(off), uint8(len(pcln.Funcdata)))) for i := range pcln.Pcdata { off = addpctab(ctxt, ftab, off, &pcln.Pcdata[i]) } diff --git a/src/cmd/link/internal/ld/util.go b/src/cmd/link/internal/ld/util.go index b80e6106ba..b5b02296a1 100644 --- a/src/cmd/link/internal/ld/util.go +++ b/src/cmd/link/internal/ld/util.go @@ -89,3 +89,13 @@ var start = time.Now() func elapsed() float64 { return time.Since(start).Seconds() } + +// contains reports whether v is in s. +func contains(s []string, v string) bool { + for _, x := range s { + if x == v { + return true + } + } + return false +} diff --git a/src/cmd/link/internal/objfile/objfile.go b/src/cmd/link/internal/objfile/objfile.go index e3800de304..3a8923b073 100644 --- a/src/cmd/link/internal/objfile/objfile.go +++ b/src/cmd/link/internal/objfile/objfile.go @@ -203,6 +203,7 @@ func (r *objReader) readSym() { overwrite: s.File = pkg + s.Lib = r.lib if dupok { s.Attr |= sym.AttrDuplicateOK } @@ -320,7 +321,6 @@ overwrite: s.FuncInfo.IsStmtSym = r.syms.Lookup(dwarf.IsStmtPrefix+s.Name, int(s.Version)) - s.Lib = r.lib if !dupok { if s.Attr.OnList() { log.Fatalf("symbol %s listed multiple times", s.Name) diff --git a/src/cmd/link/internal/ppc64/asm.go b/src/cmd/link/internal/ppc64/asm.go index 9445fbebcb..3e833b686e 100644 --- a/src/cmd/link/internal/ppc64/asm.go +++ b/src/cmd/link/internal/ppc64/asm.go @@ -716,9 +716,9 @@ func archrelocvariant(ctxt *ld.Link, r *sym.Reloc, s *sym.Symbol, t int64) int64 // overflow depends on the instruction var o1 uint32 if ctxt.Arch.ByteOrder == binary.BigEndian { - o1 = ld.Be32(s.P[r.Off-2:]) + o1 = binary.BigEndian.Uint32(s.P[r.Off-2:]) } else { - o1 = ld.Le32(s.P[r.Off:]) + o1 = binary.LittleEndian.Uint32(s.P[r.Off:]) } switch o1 >> 26 { case 24, // ori @@ -750,9 +750,9 @@ func archrelocvariant(ctxt *ld.Link, r *sym.Reloc, s *sym.Symbol, t int64) int64 // overflow depends on the instruction var o1 uint32 if ctxt.Arch.ByteOrder == binary.BigEndian { - o1 = ld.Be32(s.P[r.Off-2:]) + o1 = binary.BigEndian.Uint32(s.P[r.Off-2:]) } else { - o1 = ld.Le32(s.P[r.Off:]) + o1 = binary.LittleEndian.Uint32(s.P[r.Off:]) } switch o1 >> 26 { case 25, // oris @@ -774,9 +774,9 @@ func archrelocvariant(ctxt *ld.Link, r *sym.Reloc, s *sym.Symbol, t int64) int64 case sym.RV_POWER_DS: var o1 uint32 if ctxt.Arch.ByteOrder == binary.BigEndian { - o1 = uint32(ld.Be16(s.P[r.Off:])) + o1 = uint32(binary.BigEndian.Uint16(s.P[r.Off:])) } else { - o1 = uint32(ld.Le16(s.P[r.Off:])) + o1 = uint32(binary.LittleEndian.Uint16(s.P[r.Off:])) } if t&3 != 0 { ld.Errorf(s, "relocation for %s+%d is not aligned: %d", r.Sym.Name, r.Off, t) diff --git a/src/cmd/trace/trace.go b/src/cmd/trace/trace.go index d986b71f79..07fc4333eb 100644 --- a/src/cmd/trace/trace.go +++ b/src/cmd/trace/trace.go @@ -38,7 +38,7 @@ func httpTrace(w http.ResponseWriter, r *http.Request) { http.Error(w, err.Error(), http.StatusInternalServerError) return } - html := strings.Replace(templTrace, "{{PARAMS}}", r.Form.Encode(), -1) + html := strings.ReplaceAll(templTrace, "{{PARAMS}}", r.Form.Encode()) w.Write([]byte(html)) } @@ -685,13 +685,14 @@ func generateTrace(params *traceParams, consumer traceConsumer) error { } ctx.emitSlice(&fakeMarkStart, text) case trace.EvGCSweepStart: - slice := ctx.emitSlice(ev, "SWEEP") + slice := ctx.makeSlice(ev, "SWEEP") if done := ev.Link; done != nil && done.Args[0] != 0 { slice.Arg = struct { Swept uint64 `json:"Swept bytes"` Reclaimed uint64 `json:"Reclaimed bytes"` }{done.Args[0], done.Args[1]} } + ctx.emit(slice) case trace.EvGoStart, trace.EvGoStartLabel: info := getGInfo(ev.G) if ev.Type == trace.EvGoStartLabel { @@ -846,7 +847,11 @@ func (ctx *traceContext) proc(ev *trace.Event) uint64 { } } -func (ctx *traceContext) emitSlice(ev *trace.Event, name string) *ViewerEvent { +func (ctx *traceContext) emitSlice(ev *trace.Event, name string) { + ctx.emit(ctx.makeSlice(ev, name)) +} + +func (ctx *traceContext) makeSlice(ev *trace.Event, name string) *ViewerEvent { // If ViewerEvent.Dur is not a positive value, // trace viewer handles it as a non-terminating time interval. // Avoid it by setting the field with a small value. @@ -885,7 +890,6 @@ func (ctx *traceContext) emitSlice(ev *trace.Event, name string) *ViewerEvent { sl.Cname = colorLightGrey } } - ctx.emit(sl) return sl } diff --git a/src/cmd/vendor/golang.org/x/sys/windows/aliases.go b/src/cmd/vendor/golang.org/x/sys/windows/aliases.go new file mode 100644 index 0000000000..af3af60db9 --- /dev/null +++ b/src/cmd/vendor/golang.org/x/sys/windows/aliases.go @@ -0,0 +1,13 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build windows +// +build go1.9 + +package windows + +import "syscall" + +type Errno = syscall.Errno +type SysProcAttr = syscall.SysProcAttr diff --git a/src/cmd/vendor/golang.org/x/sys/windows/asm_windows_arm.s b/src/cmd/vendor/golang.org/x/sys/windows/asm_windows_arm.s new file mode 100644 index 0000000000..55d8b91a28 --- /dev/null +++ b/src/cmd/vendor/golang.org/x/sys/windows/asm_windows_arm.s @@ -0,0 +1,11 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "textflag.h" + +TEXT ·getprocaddress(SB),NOSPLIT,$0 + B syscall·getprocaddress(SB) + +TEXT ·loadlibrary(SB),NOSPLIT,$0 + B syscall·loadlibrary(SB) diff --git a/src/cmd/vendor/golang.org/x/sys/windows/registry/zsyscall_windows.go b/src/cmd/vendor/golang.org/x/sys/windows/registry/zsyscall_windows.go index ceebdd7726..3778075da0 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/registry/zsyscall_windows.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/registry/zsyscall_windows.go @@ -1,4 +1,4 @@ -// MACHINE GENERATED BY 'go generate' COMMAND; DO NOT EDIT +// Code generated by 'go generate'; DO NOT EDIT. package registry diff --git a/src/cmd/vendor/golang.org/x/sys/windows/security_windows.go b/src/cmd/vendor/golang.org/x/sys/windows/security_windows.go index f1ec5dc4ee..4f17a3331f 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/security_windows.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/security_windows.go @@ -296,6 +296,7 @@ const ( TOKEN_ADJUST_PRIVILEGES TOKEN_ADJUST_GROUPS TOKEN_ADJUST_DEFAULT + TOKEN_ADJUST_SESSIONID TOKEN_ALL_ACCESS = STANDARD_RIGHTS_REQUIRED | TOKEN_ASSIGN_PRIMARY | @@ -305,7 +306,8 @@ const ( TOKEN_QUERY_SOURCE | TOKEN_ADJUST_PRIVILEGES | TOKEN_ADJUST_GROUPS | - TOKEN_ADJUST_DEFAULT + TOKEN_ADJUST_DEFAULT | + TOKEN_ADJUST_SESSIONID TOKEN_READ = STANDARD_RIGHTS_READ | TOKEN_QUERY TOKEN_WRITE = STANDARD_RIGHTS_WRITE | TOKEN_ADJUST_PRIVILEGES | diff --git a/src/cmd/vendor/golang.org/x/sys/windows/service.go b/src/cmd/vendor/golang.org/x/sys/windows/service.go index 24aa90bbbe..62fc31b40b 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/service.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/service.go @@ -43,6 +43,11 @@ const ( SC_STATUS_PROCESS_INFO = 0 + SC_ACTION_NONE = 0 + SC_ACTION_RESTART = 1 + SC_ACTION_REBOOT = 2 + SC_ACTION_RUN_COMMAND = 3 + SERVICE_STOPPED = 1 SERVICE_START_PENDING = 2 SERVICE_STOP_PENDING = 3 @@ -148,6 +153,19 @@ type ENUM_SERVICE_STATUS_PROCESS struct { ServiceStatusProcess SERVICE_STATUS_PROCESS } +type SERVICE_FAILURE_ACTIONS struct { + ResetPeriod uint32 + RebootMsg *uint16 + Command *uint16 + ActionsCount uint32 + Actions *SC_ACTION +} + +type SC_ACTION struct { + Type uint32 + Delay uint32 +} + //sys CloseServiceHandle(handle Handle) (err error) = advapi32.CloseServiceHandle //sys CreateService(mgr Handle, serviceName *uint16, displayName *uint16, access uint32, srvType uint32, startType uint32, errCtl uint32, pathName *uint16, loadOrderGroup *uint16, tagId *uint32, dependencies *uint16, serviceStartName *uint16, password *uint16) (handle Handle, err error) [failretval==0] = advapi32.CreateServiceW //sys OpenService(mgr Handle, serviceName *uint16, access uint32) (handle Handle, err error) [failretval==0] = advapi32.OpenServiceW diff --git a/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/config.go b/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/config.go index 03bf41f516..d804e31f1f 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/config.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/config.go @@ -88,23 +88,11 @@ func (s *Service) Config() (Config, error) { } } - var p2 *windows.SERVICE_DESCRIPTION - n = uint32(1024) - for { - b := make([]byte, n) - p2 = (*windows.SERVICE_DESCRIPTION)(unsafe.Pointer(&b[0])) - err := windows.QueryServiceConfig2(s.Handle, - windows.SERVICE_CONFIG_DESCRIPTION, &b[0], n, &n) - if err == nil { - break - } - if err.(syscall.Errno) != syscall.ERROR_INSUFFICIENT_BUFFER { - return Config{}, err - } - if n <= uint32(len(b)) { - return Config{}, err - } + b, err := s.queryServiceConfig2(windows.SERVICE_CONFIG_DESCRIPTION) + if err != nil { + return Config{}, err } + p2 := (*windows.SERVICE_DESCRIPTION)(unsafe.Pointer(&b[0])) return Config{ ServiceType: p.ServiceType, @@ -137,3 +125,21 @@ func (s *Service) UpdateConfig(c Config) error { } return updateDescription(s.Handle, c.Description) } + +// queryServiceConfig2 calls Windows QueryServiceConfig2 with infoLevel parameter and returns retrieved service configuration information. +func (s *Service) queryServiceConfig2(infoLevel uint32) ([]byte, error) { + n := uint32(1024) + for { + b := make([]byte, n) + err := windows.QueryServiceConfig2(s.Handle, infoLevel, &b[0], n, &n) + if err == nil { + return b, nil + } + if err.(syscall.Errno) != syscall.ERROR_INSUFFICIENT_BUFFER { + return nil, err + } + if n <= uint32(len(b)) { + return nil, err + } + } +} diff --git a/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/mgr_test.go b/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/mgr_test.go index 1569a22177..9171f5bcf1 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/mgr_test.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/mgr_test.go @@ -95,6 +95,113 @@ func testConfig(t *testing.T, s *mgr.Service, should mgr.Config) mgr.Config { return is } +func testRecoveryActions(t *testing.T, s *mgr.Service, should []mgr.RecoveryAction) { + is, err := s.RecoveryActions() + if err != nil { + t.Fatalf("RecoveryActions failed: %s", err) + } + if len(should) != len(is) { + t.Errorf("recovery action mismatch: contains %v actions, but should have %v", len(is), len(should)) + } + for i, _ := range is { + if should[i].Type != is[i].Type { + t.Errorf("recovery action mismatch: Type is %v, but should have %v", is[i].Type, should[i].Type) + } + if should[i].Delay != is[i].Delay { + t.Errorf("recovery action mismatch: Delay is %v, but should have %v", is[i].Delay, should[i].Delay) + } + } +} + +func testResetPeriod(t *testing.T, s *mgr.Service, should uint32) { + is, err := s.ResetPeriod() + if err != nil { + t.Fatalf("ResetPeriod failed: %s", err) + } + if should != is { + t.Errorf("reset period mismatch: reset period is %v, but should have %v", is, should) + } +} + +func testSetRecoveryActions(t *testing.T, s *mgr.Service) { + r := []mgr.RecoveryAction{ + mgr.RecoveryAction{ + Type: mgr.NoAction, + Delay: 60000 * time.Millisecond, + }, + mgr.RecoveryAction{ + Type: mgr.ServiceRestart, + Delay: 4 * time.Minute, + }, + mgr.RecoveryAction{ + Type: mgr.ServiceRestart, + Delay: time.Minute, + }, + mgr.RecoveryAction{ + Type: mgr.RunCommand, + Delay: 4000 * time.Millisecond, + }, + } + + // 4 recovery actions with reset period + err := s.SetRecoveryActions(r, uint32(10000)) + if err != nil { + t.Fatalf("SetRecoveryActions failed: %v", err) + } + testRecoveryActions(t, s, r) + testResetPeriod(t, s, uint32(10000)) + + // Infinite reset period + err = s.SetRecoveryActions(r, syscall.INFINITE) + if err != nil { + t.Fatalf("SetRecoveryActions failed: %v", err) + } + testRecoveryActions(t, s, r) + testResetPeriod(t, s, syscall.INFINITE) + + // nil recovery actions + err = s.SetRecoveryActions(nil, 0) + if err.Error() != "recoveryActions cannot be nil" { + t.Fatalf("SetRecoveryActions failed with unexpected error message of %q", err) + } + + // Delete all recovery actions and reset period + err = s.ResetRecoveryActions() + if err != nil { + t.Fatalf("ResetRecoveryActions failed: %v", err) + } + testRecoveryActions(t, s, nil) + testResetPeriod(t, s, 0) +} + +func testRebootMessage(t *testing.T, s *mgr.Service, should string) { + err := s.SetRebootMessage(should) + if err != nil { + t.Fatalf("SetRebootMessage failed: %v", err) + } + is, err := s.RebootMessage() + if err != nil { + t.Fatalf("RebootMessage failed: %v", err) + } + if should != is { + t.Errorf("reboot message mismatch: message is %q, but should have %q", is, should) + } +} + +func testRecoveryCommand(t *testing.T, s *mgr.Service, should string) { + err := s.SetRecoveryCommand(should) + if err != nil { + t.Fatalf("SetRecoveryCommand failed: %v", err) + } + is, err := s.RecoveryCommand() + if err != nil { + t.Fatalf("RecoveryCommand failed: %v", err) + } + if should != is { + t.Errorf("recovery command mismatch: command is %q, but should have %q", is, should) + } +} + func remove(t *testing.T, s *mgr.Service) { err := s.Delete() if err != nil { @@ -165,5 +272,11 @@ func TestMyService(t *testing.T) { t.Errorf("ListServices failed to find %q service", name) } + testSetRecoveryActions(t, s) + testRebootMessage(t, s, "myservice failed") + testRebootMessage(t, s, "") // delete reboot message + testRecoveryCommand(t, s, "sc query myservice") + testRecoveryCommand(t, s, "") // delete recovery command + remove(t, s) } diff --git a/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/recovery.go b/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/recovery.go new file mode 100644 index 0000000000..71ce2b8199 --- /dev/null +++ b/src/cmd/vendor/golang.org/x/sys/windows/svc/mgr/recovery.go @@ -0,0 +1,135 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build windows + +package mgr + +import ( + "errors" + "syscall" + "time" + "unsafe" + + "golang.org/x/sys/windows" +) + +const ( + // Possible recovery actions that the service control manager can perform. + NoAction = windows.SC_ACTION_NONE // no action + ComputerReboot = windows.SC_ACTION_REBOOT // reboot the computer + ServiceRestart = windows.SC_ACTION_RESTART // restart the service + RunCommand = windows.SC_ACTION_RUN_COMMAND // run a command +) + +// RecoveryAction represents an action that the service control manager can perform when service fails. +// A service is considered failed when it terminates without reporting a status of SERVICE_STOPPED to the service controller. +type RecoveryAction struct { + Type int // one of NoAction, ComputerReboot, ServiceRestart or RunCommand + Delay time.Duration // the time to wait before performing the specified action +} + +// SetRecoveryActions sets actions that service controller performs when service fails and +// the time after which to reset the service failure count to zero if there are no failures, in seconds. +// Specify INFINITE to indicate that service failure count should never be reset. +func (s *Service) SetRecoveryActions(recoveryActions []RecoveryAction, resetPeriod uint32) error { + if recoveryActions == nil { + return errors.New("recoveryActions cannot be nil") + } + actions := []windows.SC_ACTION{} + for _, a := range recoveryActions { + action := windows.SC_ACTION{ + Type: uint32(a.Type), + Delay: uint32(a.Delay.Nanoseconds() / 1000000), + } + actions = append(actions, action) + } + rActions := windows.SERVICE_FAILURE_ACTIONS{ + ActionsCount: uint32(len(actions)), + Actions: &actions[0], + ResetPeriod: resetPeriod, + } + return windows.ChangeServiceConfig2(s.Handle, windows.SERVICE_CONFIG_FAILURE_ACTIONS, (*byte)(unsafe.Pointer(&rActions))) +} + +// RecoveryActions returns actions that service controller performs when service fails. +// The service control manager counts the number of times service s has failed since the system booted. +// The count is reset to 0 if the service has not failed for ResetPeriod seconds. +// When the service fails for the Nth time, the service controller performs the action specified in element [N-1] of returned slice. +// If N is greater than slice length, the service controller repeats the last action in the slice. +func (s *Service) RecoveryActions() ([]RecoveryAction, error) { + b, err := s.queryServiceConfig2(windows.SERVICE_CONFIG_FAILURE_ACTIONS) + if err != nil { + return nil, err + } + p := (*windows.SERVICE_FAILURE_ACTIONS)(unsafe.Pointer(&b[0])) + if p.Actions == nil { + return nil, err + } + + var recoveryActions []RecoveryAction + actions := (*[1024]windows.SC_ACTION)(unsafe.Pointer(p.Actions))[:p.ActionsCount] + for _, action := range actions { + recoveryActions = append(recoveryActions, RecoveryAction{Type: int(action.Type), Delay: time.Duration(action.Delay) * time.Millisecond}) + } + return recoveryActions, nil +} + +// ResetRecoveryActions deletes both reset period and array of failure actions. +func (s *Service) ResetRecoveryActions() error { + actions := make([]windows.SC_ACTION, 1) + rActions := windows.SERVICE_FAILURE_ACTIONS{ + Actions: &actions[0], + } + return windows.ChangeServiceConfig2(s.Handle, windows.SERVICE_CONFIG_FAILURE_ACTIONS, (*byte)(unsafe.Pointer(&rActions))) +} + +// ResetPeriod is the time after which to reset the service failure +// count to zero if there are no failures, in seconds. +func (s *Service) ResetPeriod() (uint32, error) { + b, err := s.queryServiceConfig2(windows.SERVICE_CONFIG_FAILURE_ACTIONS) + if err != nil { + return 0, err + } + p := (*windows.SERVICE_FAILURE_ACTIONS)(unsafe.Pointer(&b[0])) + return p.ResetPeriod, nil +} + +// SetRebootMessage sets service s reboot message. +// If msg is "", the reboot message is deleted and no message is broadcast. +func (s *Service) SetRebootMessage(msg string) error { + rActions := windows.SERVICE_FAILURE_ACTIONS{ + RebootMsg: syscall.StringToUTF16Ptr(msg), + } + return windows.ChangeServiceConfig2(s.Handle, windows.SERVICE_CONFIG_FAILURE_ACTIONS, (*byte)(unsafe.Pointer(&rActions))) +} + +// RebootMessage is broadcast to server users before rebooting in response to the ComputerReboot service controller action. +func (s *Service) RebootMessage() (string, error) { + b, err := s.queryServiceConfig2(windows.SERVICE_CONFIG_FAILURE_ACTIONS) + if err != nil { + return "", err + } + p := (*windows.SERVICE_FAILURE_ACTIONS)(unsafe.Pointer(&b[0])) + return toString(p.RebootMsg), nil +} + +// SetRecoveryCommand sets the command line of the process to execute in response to the RunCommand service controller action. +// If cmd is "", the command is deleted and no program is run when the service fails. +func (s *Service) SetRecoveryCommand(cmd string) error { + rActions := windows.SERVICE_FAILURE_ACTIONS{ + Command: syscall.StringToUTF16Ptr(cmd), + } + return windows.ChangeServiceConfig2(s.Handle, windows.SERVICE_CONFIG_FAILURE_ACTIONS, (*byte)(unsafe.Pointer(&rActions))) +} + +// RecoveryCommand is the command line of the process to execute in response to the RunCommand service controller action. This process runs under the same account as the service. +func (s *Service) RecoveryCommand() (string, error) { + b, err := s.queryServiceConfig2(windows.SERVICE_CONFIG_FAILURE_ACTIONS) + if err != nil { + return "", err + } + p := (*windows.SERVICE_FAILURE_ACTIONS)(unsafe.Pointer(&b[0])) + return toString(p.Command), nil +} diff --git a/src/cmd/vendor/golang.org/x/sys/windows/svc/sys_arm.s b/src/cmd/vendor/golang.org/x/sys/windows/svc/sys_arm.s new file mode 100644 index 0000000000..33c692a8de --- /dev/null +++ b/src/cmd/vendor/golang.org/x/sys/windows/svc/sys_arm.s @@ -0,0 +1,38 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build windows + +#include "textflag.h" + +// func servicemain(argc uint32, argv **uint16) +TEXT ·servicemain(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4, R14], (R13) // push {r4, lr} + MOVW R13, R4 + BIC $0x7, R13 // alignment for ABI + + MOVW R0, ·sArgc(SB) + MOVW R1, ·sArgv(SB) + + MOVW ·sName(SB), R0 + MOVW ·ctlHandlerExProc(SB), R1 + MOVW $0, R2 + MOVW ·cRegisterServiceCtrlHandlerExW(SB), R3 + BL (R3) + CMP $0, R0 + BEQ exit + MOVW R0, ·ssHandle(SB) + + MOVW ·goWaitsH(SB), R0 + MOVW ·cSetEvent(SB), R1 + BL (R1) + + MOVW ·cWaitsH(SB), R0 + MOVW $-1, R1 + MOVW ·cWaitForSingleObject(SB), R2 + BL (R2) + +exit: + MOVW R4, R13 // free extra stack space + MOVM.IA.W (R13), [R4, R15] // pop {r4, pc} diff --git a/src/cmd/vendor/golang.org/x/sys/windows/syscall_windows.go b/src/cmd/vendor/golang.org/x/sys/windows/syscall_windows.go index 1e9f4bb4a3..8a00b71f1d 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/syscall_windows.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/syscall_windows.go @@ -112,12 +112,14 @@ func Getpagesize() int { return 4096 } // NewCallback converts a Go function to a function pointer conforming to the stdcall calling convention. // This is useful when interoperating with Windows code requiring callbacks. +// The argument is expected to be a function with with one uintptr-sized result. The function must not have arguments with size larger than the size of uintptr. func NewCallback(fn interface{}) uintptr { return syscall.NewCallback(fn) } // NewCallbackCDecl converts a Go function to a function pointer conforming to the cdecl calling convention. // This is useful when interoperating with Windows code requiring callbacks. +// The argument is expected to be a function with with one uintptr-sized result. The function must not have arguments with size larger than the size of uintptr. func NewCallbackCDecl(fn interface{}) uintptr { return syscall.NewCallbackCDecl(fn) } @@ -653,7 +655,7 @@ type RawSockaddr struct { type RawSockaddrAny struct { Addr RawSockaddr - Pad [96]int8 + Pad [100]int8 } type Sockaddr interface { @@ -702,19 +704,69 @@ func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, int32, error) { return unsafe.Pointer(&sa.raw), int32(unsafe.Sizeof(sa.raw)), nil } +type RawSockaddrUnix struct { + Family uint16 + Path [UNIX_PATH_MAX]int8 +} + type SockaddrUnix struct { Name string + raw RawSockaddrUnix } func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, int32, error) { - // TODO(brainman): implement SockaddrUnix.sockaddr() - return nil, 0, syscall.EWINDOWS + name := sa.Name + n := len(name) + if n > len(sa.raw.Path) { + return nil, 0, syscall.EINVAL + } + if n == len(sa.raw.Path) && name[0] != '@' { + return nil, 0, syscall.EINVAL + } + sa.raw.Family = AF_UNIX + for i := 0; i < n; i++ { + sa.raw.Path[i] = int8(name[i]) + } + // length is family (uint16), name, NUL. + sl := int32(2) + if n > 0 { + sl += int32(n) + 1 + } + if sa.raw.Path[0] == '@' { + sa.raw.Path[0] = 0 + // Don't count trailing NUL for abstract address. + sl-- + } + + return unsafe.Pointer(&sa.raw), sl, nil } func (rsa *RawSockaddrAny) Sockaddr() (Sockaddr, error) { switch rsa.Addr.Family { case AF_UNIX: - return nil, syscall.EWINDOWS + pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa)) + sa := new(SockaddrUnix) + if pp.Path[0] == 0 { + // "Abstract" Unix domain socket. + // Rewrite leading NUL as @ for textual display. + // (This is the standard convention.) + // Not friendly to overwrite in place, + // but the callers below don't care. + pp.Path[0] = '@' + } + + // Assume path ends at NUL. + // This is not technically the Linux semantics for + // abstract Unix domain sockets--they are supposed + // to be uninterpreted fixed-size binary blobs--but + // everyone uses this convention. + n := 0 + for n < len(pp.Path) && pp.Path[n] != 0 { + n++ + } + bytes := (*[10000]byte)(unsafe.Pointer(&pp.Path[0]))[0:n] + sa.Name = string(bytes) + return sa, nil case AF_INET: pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa)) diff --git a/src/cmd/vendor/golang.org/x/sys/windows/syscall_windows_test.go b/src/cmd/vendor/golang.org/x/sys/windows/syscall_windows_test.go index 9c7133cc41..0e27464e8c 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/syscall_windows_test.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/syscall_windows_test.go @@ -105,3 +105,9 @@ func ExampleLoadLibrary() { build := uint16(r >> 16) print("windows version ", major, ".", minor, " (Build ", build, ")\n") } + +func TestTOKEN_ALL_ACCESS(t *testing.T) { + if windows.TOKEN_ALL_ACCESS != 0xF01FF { + t.Errorf("TOKEN_ALL_ACCESS = %x, want 0xF01FF", windows.TOKEN_ALL_ACCESS) + } +} diff --git a/src/cmd/vendor/golang.org/x/sys/windows/types_windows.go b/src/cmd/vendor/golang.org/x/sys/windows/types_windows.go index 52c2037b68..141ca81bd7 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/types_windows.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/types_windows.go @@ -94,16 +94,29 @@ const ( FILE_APPEND_DATA = 0x00000004 FILE_WRITE_ATTRIBUTES = 0x00000100 - FILE_SHARE_READ = 0x00000001 - FILE_SHARE_WRITE = 0x00000002 - FILE_SHARE_DELETE = 0x00000004 - FILE_ATTRIBUTE_READONLY = 0x00000001 - FILE_ATTRIBUTE_HIDDEN = 0x00000002 - FILE_ATTRIBUTE_SYSTEM = 0x00000004 - FILE_ATTRIBUTE_DIRECTORY = 0x00000010 - FILE_ATTRIBUTE_ARCHIVE = 0x00000020 - FILE_ATTRIBUTE_NORMAL = 0x00000080 - FILE_ATTRIBUTE_REPARSE_POINT = 0x00000400 + FILE_SHARE_READ = 0x00000001 + FILE_SHARE_WRITE = 0x00000002 + FILE_SHARE_DELETE = 0x00000004 + + FILE_ATTRIBUTE_READONLY = 0x00000001 + FILE_ATTRIBUTE_HIDDEN = 0x00000002 + FILE_ATTRIBUTE_SYSTEM = 0x00000004 + FILE_ATTRIBUTE_DIRECTORY = 0x00000010 + FILE_ATTRIBUTE_ARCHIVE = 0x00000020 + FILE_ATTRIBUTE_DEVICE = 0x00000040 + FILE_ATTRIBUTE_NORMAL = 0x00000080 + FILE_ATTRIBUTE_TEMPORARY = 0x00000100 + FILE_ATTRIBUTE_SPARSE_FILE = 0x00000200 + FILE_ATTRIBUTE_REPARSE_POINT = 0x00000400 + FILE_ATTRIBUTE_COMPRESSED = 0x00000800 + FILE_ATTRIBUTE_OFFLINE = 0x00001000 + FILE_ATTRIBUTE_NOT_CONTENT_INDEXED = 0x00002000 + FILE_ATTRIBUTE_ENCRYPTED = 0x00004000 + FILE_ATTRIBUTE_INTEGRITY_STREAM = 0x00008000 + FILE_ATTRIBUTE_VIRTUAL = 0x00010000 + FILE_ATTRIBUTE_NO_SCRUB_DATA = 0x00020000 + FILE_ATTRIBUTE_RECALL_ON_OPEN = 0x00040000 + FILE_ATTRIBUTE_RECALL_ON_DATA_ACCESS = 0x00400000 INVALID_FILE_ATTRIBUTES = 0xffffffff @@ -257,15 +270,87 @@ const ( USAGE_MATCH_TYPE_AND = 0 USAGE_MATCH_TYPE_OR = 1 + /* msgAndCertEncodingType values for CertOpenStore function */ X509_ASN_ENCODING = 0x00000001 PKCS_7_ASN_ENCODING = 0x00010000 - CERT_STORE_PROV_MEMORY = 2 - - CERT_STORE_ADD_ALWAYS = 4 + /* storeProvider values for CertOpenStore function */ + CERT_STORE_PROV_MSG = 1 + CERT_STORE_PROV_MEMORY = 2 + CERT_STORE_PROV_FILE = 3 + CERT_STORE_PROV_REG = 4 + CERT_STORE_PROV_PKCS7 = 5 + CERT_STORE_PROV_SERIALIZED = 6 + CERT_STORE_PROV_FILENAME_A = 7 + CERT_STORE_PROV_FILENAME_W = 8 + CERT_STORE_PROV_FILENAME = CERT_STORE_PROV_FILENAME_W + CERT_STORE_PROV_SYSTEM_A = 9 + CERT_STORE_PROV_SYSTEM_W = 10 + CERT_STORE_PROV_SYSTEM = CERT_STORE_PROV_SYSTEM_W + CERT_STORE_PROV_COLLECTION = 11 + CERT_STORE_PROV_SYSTEM_REGISTRY_A = 12 + CERT_STORE_PROV_SYSTEM_REGISTRY_W = 13 + CERT_STORE_PROV_SYSTEM_REGISTRY = CERT_STORE_PROV_SYSTEM_REGISTRY_W + CERT_STORE_PROV_PHYSICAL_W = 14 + CERT_STORE_PROV_PHYSICAL = CERT_STORE_PROV_PHYSICAL_W + CERT_STORE_PROV_SMART_CARD_W = 15 + CERT_STORE_PROV_SMART_CARD = CERT_STORE_PROV_SMART_CARD_W + CERT_STORE_PROV_LDAP_W = 16 + CERT_STORE_PROV_LDAP = CERT_STORE_PROV_LDAP_W + CERT_STORE_PROV_PKCS12 = 17 + /* store characteristics (low WORD of flag) for CertOpenStore function */ + CERT_STORE_NO_CRYPT_RELEASE_FLAG = 0x00000001 + CERT_STORE_SET_LOCALIZED_NAME_FLAG = 0x00000002 CERT_STORE_DEFER_CLOSE_UNTIL_LAST_FREE_FLAG = 0x00000004 + CERT_STORE_DELETE_FLAG = 0x00000010 + CERT_STORE_UNSAFE_PHYSICAL_FLAG = 0x00000020 + CERT_STORE_SHARE_STORE_FLAG = 0x00000040 + CERT_STORE_SHARE_CONTEXT_FLAG = 0x00000080 + CERT_STORE_MANIFOLD_FLAG = 0x00000100 + CERT_STORE_ENUM_ARCHIVED_FLAG = 0x00000200 + CERT_STORE_UPDATE_KEYID_FLAG = 0x00000400 + CERT_STORE_BACKUP_RESTORE_FLAG = 0x00000800 + CERT_STORE_MAXIMUM_ALLOWED_FLAG = 0x00001000 + CERT_STORE_CREATE_NEW_FLAG = 0x00002000 + CERT_STORE_OPEN_EXISTING_FLAG = 0x00004000 + CERT_STORE_READONLY_FLAG = 0x00008000 + + /* store locations (high WORD of flag) for CertOpenStore function */ + CERT_SYSTEM_STORE_CURRENT_USER = 0x00010000 + CERT_SYSTEM_STORE_LOCAL_MACHINE = 0x00020000 + CERT_SYSTEM_STORE_CURRENT_SERVICE = 0x00040000 + CERT_SYSTEM_STORE_SERVICES = 0x00050000 + CERT_SYSTEM_STORE_USERS = 0x00060000 + CERT_SYSTEM_STORE_CURRENT_USER_GROUP_POLICY = 0x00070000 + CERT_SYSTEM_STORE_LOCAL_MACHINE_GROUP_POLICY = 0x00080000 + CERT_SYSTEM_STORE_LOCAL_MACHINE_ENTERPRISE = 0x00090000 + CERT_SYSTEM_STORE_UNPROTECTED_FLAG = 0x40000000 + CERT_SYSTEM_STORE_RELOCATE_FLAG = 0x80000000 + + /* Miscellaneous high-WORD flags for CertOpenStore function */ + CERT_REGISTRY_STORE_REMOTE_FLAG = 0x00010000 + CERT_REGISTRY_STORE_SERIALIZED_FLAG = 0x00020000 + CERT_REGISTRY_STORE_ROAMING_FLAG = 0x00040000 + CERT_REGISTRY_STORE_MY_IE_DIRTY_FLAG = 0x00080000 + CERT_REGISTRY_STORE_LM_GPT_FLAG = 0x01000000 + CERT_REGISTRY_STORE_CLIENT_GPT_FLAG = 0x80000000 + CERT_FILE_STORE_COMMIT_ENABLE_FLAG = 0x00010000 + CERT_LDAP_STORE_SIGN_FLAG = 0x00010000 + CERT_LDAP_STORE_AREC_EXCLUSIVE_FLAG = 0x00020000 + CERT_LDAP_STORE_OPENED_FLAG = 0x00040000 + CERT_LDAP_STORE_UNBIND_FLAG = 0x00080000 + /* addDisposition values for CertAddCertificateContextToStore function */ + CERT_STORE_ADD_NEW = 1 + CERT_STORE_ADD_USE_EXISTING = 2 + CERT_STORE_ADD_REPLACE_EXISTING = 3 + CERT_STORE_ADD_ALWAYS = 4 + CERT_STORE_ADD_REPLACE_EXISTING_INHERIT_PROPERTIES = 5 + CERT_STORE_ADD_NEWER = 6 + CERT_STORE_ADD_NEWER_INHERIT_PROPERTIES = 7 + + /* ErrorStatus values for CertTrustStatus struct */ CERT_TRUST_NO_ERROR = 0x00000000 CERT_TRUST_IS_NOT_TIME_VALID = 0x00000001 CERT_TRUST_IS_REVOKED = 0x00000004 @@ -282,11 +367,31 @@ const ( CERT_TRUST_HAS_NOT_DEFINED_NAME_CONSTRAINT = 0x00002000 CERT_TRUST_HAS_NOT_PERMITTED_NAME_CONSTRAINT = 0x00004000 CERT_TRUST_HAS_EXCLUDED_NAME_CONSTRAINT = 0x00008000 + CERT_TRUST_IS_PARTIAL_CHAIN = 0x00010000 + CERT_TRUST_CTL_IS_NOT_TIME_VALID = 0x00020000 + CERT_TRUST_CTL_IS_NOT_SIGNATURE_VALID = 0x00040000 + CERT_TRUST_CTL_IS_NOT_VALID_FOR_USAGE = 0x00080000 + CERT_TRUST_HAS_WEAK_SIGNATURE = 0x00100000 CERT_TRUST_IS_OFFLINE_REVOCATION = 0x01000000 CERT_TRUST_NO_ISSUANCE_CHAIN_POLICY = 0x02000000 CERT_TRUST_IS_EXPLICIT_DISTRUST = 0x04000000 CERT_TRUST_HAS_NOT_SUPPORTED_CRITICAL_EXT = 0x08000000 + /* InfoStatus values for CertTrustStatus struct */ + CERT_TRUST_HAS_EXACT_MATCH_ISSUER = 0x00000001 + CERT_TRUST_HAS_KEY_MATCH_ISSUER = 0x00000002 + CERT_TRUST_HAS_NAME_MATCH_ISSUER = 0x00000004 + CERT_TRUST_IS_SELF_SIGNED = 0x00000008 + CERT_TRUST_HAS_PREFERRED_ISSUER = 0x00000100 + CERT_TRUST_HAS_ISSUANCE_CHAIN_POLICY = 0x00000400 + CERT_TRUST_HAS_VALID_NAME_CONSTRAINTS = 0x00000400 + CERT_TRUST_IS_PEER_TRUSTED = 0x00000800 + CERT_TRUST_HAS_CRL_VALIDITY_EXTENDED = 0x00001000 + CERT_TRUST_IS_FROM_EXCLUSIVE_TRUST_STORE = 0x00002000 + CERT_TRUST_IS_CA_TRUSTED = 0x00004000 + CERT_TRUST_IS_COMPLEX_CHAIN = 0x00010000 + + /* policyOID values for CertVerifyCertificateChainPolicy function */ CERT_CHAIN_POLICY_BASE = 1 CERT_CHAIN_POLICY_AUTHENTICODE = 2 CERT_CHAIN_POLICY_AUTHENTICODE_TS = 3 @@ -295,6 +400,7 @@ const ( CERT_CHAIN_POLICY_NT_AUTH = 6 CERT_CHAIN_POLICY_MICROSOFT_ROOT = 7 CERT_CHAIN_POLICY_EV = 8 + CERT_CHAIN_POLICY_SSL_F12 = 9 CERT_E_EXPIRED = 0x800B0101 CERT_E_ROLE = 0x800B0103 @@ -302,8 +408,16 @@ const ( CERT_E_UNTRUSTEDROOT = 0x800B0109 CERT_E_CN_NO_MATCH = 0x800B010F + /* AuthType values for SSLExtraCertChainPolicyPara struct */ AUTHTYPE_CLIENT = 1 AUTHTYPE_SERVER = 2 + + /* Checks values for SSLExtraCertChainPolicyPara struct */ + SECURITY_FLAG_IGNORE_REVOCATION = 0x00000080 + SECURITY_FLAG_IGNORE_UNKNOWN_CA = 0x00000100 + SECURITY_FLAG_IGNORE_WRONG_USAGE = 0x00000200 + SECURITY_FLAG_IGNORE_CERT_CN_INVALID = 0x00001000 + SECURITY_FLAG_IGNORE_CERT_DATE_INVALID = 0x00002000 ) var ( @@ -312,6 +426,14 @@ var ( OID_SGC_NETSCAPE = []byte("2.16.840.1.113730.4.1\x00") ) +// Pointer represents a pointer to an arbitrary Windows type. +// +// Pointer-typed fields may point to one of many different types. It's +// up to the caller to provide a pointer to the appropriate type, cast +// to Pointer. The caller must obey the unsafe.Pointer rules while +// doing so. +type Pointer *struct{} + // Invented values to support what package os expects. type Timeval struct { Sec int32 @@ -880,11 +1002,15 @@ type MibIfRow struct { Descr [MAXLEN_IFDESCR]byte } +type CertInfo struct { + // Not implemented +} + type CertContext struct { EncodingType uint32 EncodedCert *byte Length uint32 - CertInfo uintptr + CertInfo *CertInfo Store Handle } @@ -899,12 +1025,16 @@ type CertChainContext struct { RevocationFreshnessTime uint32 } +type CertTrustListInfo struct { + // Not implemented +} + type CertSimpleChain struct { Size uint32 TrustStatus CertTrustStatus NumElements uint32 Elements **CertChainElement - TrustListInfo uintptr + TrustListInfo *CertTrustListInfo HasRevocationFreshnessTime uint32 RevocationFreshnessTime uint32 } @@ -919,14 +1049,18 @@ type CertChainElement struct { ExtendedErrorInfo *uint16 } +type CertRevocationCrlInfo struct { + // Not implemented +} + type CertRevocationInfo struct { Size uint32 RevocationResult uint32 RevocationOid *byte - OidSpecificInfo uintptr + OidSpecificInfo Pointer HasFreshnessTime uint32 FreshnessTime uint32 - CrlInfo uintptr // *CertRevocationCrlInfo + CrlInfo *CertRevocationCrlInfo } type CertTrustStatus struct { @@ -957,7 +1091,7 @@ type CertChainPara struct { type CertChainPolicyPara struct { Size uint32 Flags uint32 - ExtraPolicyPara uintptr + ExtraPolicyPara Pointer } type SSLExtraCertChainPolicyPara struct { @@ -972,7 +1106,7 @@ type CertChainPolicyStatus struct { Error uint32 ChainIndex uint32 ElementIndex uint32 - ExtraPolicyStatus uintptr + ExtraPolicyStatus Pointer } const ( @@ -1319,7 +1453,7 @@ type SmallRect struct { Bottom int16 } -// Used with GetConsoleScreenBuffer to retreive information about a console +// Used with GetConsoleScreenBuffer to retrieve information about a console // screen buffer. See // https://docs.microsoft.com/en-us/windows/console/console-screen-buffer-info-str // for details. @@ -1331,3 +1465,5 @@ type ConsoleScreenBufferInfo struct { Window SmallRect MaximumWindowSize Coord } + +const UNIX_PATH_MAX = 108 // defined in afunix.h diff --git a/src/cmd/vendor/golang.org/x/sys/windows/types_windows_arm.go b/src/cmd/vendor/golang.org/x/sys/windows/types_windows_arm.go new file mode 100644 index 0000000000..74571e3600 --- /dev/null +++ b/src/cmd/vendor/golang.org/x/sys/windows/types_windows_arm.go @@ -0,0 +1,22 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package windows + +type WSAData struct { + Version uint16 + HighVersion uint16 + Description [WSADESCRIPTION_LEN + 1]byte + SystemStatus [WSASYS_STATUS_LEN + 1]byte + MaxSockets uint16 + MaxUdpDg uint16 + VendorInfo *byte +} + +type Servent struct { + Name *byte + Aliases **byte + Port uint16 + Proto *byte +} diff --git a/src/cmd/vendor/golang.org/x/sys/windows/zsyscall_windows.go b/src/cmd/vendor/golang.org/x/sys/windows/zsyscall_windows.go index 318c61634e..fc56aec035 100644 --- a/src/cmd/vendor/golang.org/x/sys/windows/zsyscall_windows.go +++ b/src/cmd/vendor/golang.org/x/sys/windows/zsyscall_windows.go @@ -1,4 +1,4 @@ -// MACHINE GENERATED BY 'go generate' COMMAND; DO NOT EDIT +// Code generated by 'go generate'; DO NOT EDIT. package windows diff --git a/src/cmd/vendor/vendor.json b/src/cmd/vendor/vendor.json index 8009661879..6e077e4ae1 100644 --- a/src/cmd/vendor/vendor.json +++ b/src/cmd/vendor/vendor.json @@ -131,40 +131,40 @@ "revisionTime": "2018-06-27T13:57:12Z" }, { - "checksumSHA1": "y0x0I9zDxnxn9nCxwP/MdPyq1E8=", + "checksumSHA1": "s+lofQ+SCdhmy0cQp9FpdQncuuI=", "path": "golang.org/x/sys/windows", - "revision": "c11f84a56e43e20a78cee75a7c034031ecf57d1f", - "revisionTime": "2018-05-25T13:55:20Z" + "revision": "90868a75fefd03942536221d7c0e2f84ec62a668", + "revisionTime": "2018-08-01T20:46:00Z" }, { - "checksumSHA1": "BnZkq/3Ejb7961bDhybRraW6jzI=", + "checksumSHA1": "yEg3f1MGwuyDh5NrNEGkWKlTyqY=", "path": "golang.org/x/sys/windows/registry", - "revision": "c11f84a56e43e20a78cee75a7c034031ecf57d1f", - "revisionTime": "2018-05-25T13:55:20Z" + "revision": "90868a75fefd03942536221d7c0e2f84ec62a668", + "revisionTime": "2018-08-01T20:46:00Z" }, { - "checksumSHA1": "dQbFeoiAxfB3WFFVcAdeSwSgeDk=", + "checksumSHA1": "ZDwqsuoZqQq/XMQ0R0dJ4oK41lU=", "path": "golang.org/x/sys/windows/svc", - "revision": "c11f84a56e43e20a78cee75a7c034031ecf57d1f", - "revisionTime": "2018-05-25T13:55:20Z" + "revision": "90868a75fefd03942536221d7c0e2f84ec62a668", + "revisionTime": "2018-08-01T20:46:00Z" }, { "checksumSHA1": "e9KJPWrdqg5PMkbE2w60Io8rY4M=", "path": "golang.org/x/sys/windows/svc/debug", - "revision": "c11f84a56e43e20a78cee75a7c034031ecf57d1f", - "revisionTime": "2018-05-25T13:55:20Z" + "revision": "90868a75fefd03942536221d7c0e2f84ec62a668", + "revisionTime": "2018-08-01T20:46:00Z" }, { "checksumSHA1": "dz53pQfqAnXG8HdJj+nazXN9YRw=", "path": "golang.org/x/sys/windows/svc/eventlog", - "revision": "c11f84a56e43e20a78cee75a7c034031ecf57d1f", - "revisionTime": "2018-05-25T13:55:20Z" + "revision": "90868a75fefd03942536221d7c0e2f84ec62a668", + "revisionTime": "2018-08-01T20:46:00Z" }, { - "checksumSHA1": "wz+0tf0Z7cVBaz/35P1m1cAiI7k=", + "checksumSHA1": "vV6Mr/b+1GaHiHLnq2zEejQJVec=", "path": "golang.org/x/sys/windows/svc/mgr", - "revision": "c11f84a56e43e20a78cee75a7c034031ecf57d1f", - "revisionTime": "2018-05-25T13:55:20Z" + "revision": "90868a75fefd03942536221d7c0e2f84ec62a668", + "revisionTime": "2018-08-01T20:46:00Z" } ], "rootPath": "/cmd" diff --git a/src/cmd/vet/all/main.go b/src/cmd/vet/all/main.go index e7fe4edc2a..7e4a68101f 100644 --- a/src/cmd/vet/all/main.go +++ b/src/cmd/vet/all/main.go @@ -192,9 +192,9 @@ func vetPlatforms(pp []platform) { } func (p platform) vet() { - if p.os == "linux" && p.arch == "riscv64" { - // TODO(tklauser): enable as soon as the riscv64 port has fully landed - fmt.Println("skipping linux/riscv64") + if p.os == "linux" && (p.arch == "riscv64" || p.arch == "sparc64") { + // TODO(tklauser): enable as soon as these ports have fully landed + fmt.Printf("skipping %s/%s\n", p.os, p.arch) return } @@ -204,6 +204,12 @@ func (p platform) vet() { return } + if p.os == "aix" && p.arch == "ppc64" { + // TODO(aix): enable as soon as the aix/ppc64 port has fully landed + fmt.Println("skipping aix/ppc64") + return + } + var buf bytes.Buffer fmt.Fprintf(&buf, "go run main.go -p %s\n", p) diff --git a/src/cmd/vet/all/whitelist/all.txt b/src/cmd/vet/all/whitelist/all.txt index b974d21c6a..5425f84fc6 100644 --- a/src/cmd/vet/all/whitelist/all.txt +++ b/src/cmd/vet/all/whitelist/all.txt @@ -24,6 +24,7 @@ runtime/asm_ARCHSUFF.s: [GOARCH] gcWriteBarrier: function gcWriteBarrier missing // in bad situations that vet can also detect statically. encoding/json/decode_test.go: struct field m has json tag but is not exported encoding/json/decode_test.go: struct field m2 has json tag but is not exported +encoding/json/decode_test.go: struct field s has json tag but is not exported encoding/json/tagkey_test.go: struct field tag `:"BadFormat"` not compatible with reflect.StructTag.Get: bad syntax for struct tag key runtime/testdata/testprog/deadlock.go: unreachable code runtime/testdata/testprog/deadlock.go: unreachable code diff --git a/src/cmd/vet/all/whitelist/windows_386.txt b/src/cmd/vet/all/whitelist/windows_386.txt index 788684a49d..d910022ef6 100644 --- a/src/cmd/vet/all/whitelist/windows_386.txt +++ b/src/cmd/vet/all/whitelist/windows_386.txt @@ -3,7 +3,6 @@ runtime/sys_windows_386.s: [386] profileloop: use of 4(SP) points beyond argument frame runtime/sys_windows_386.s: [386] ctrlhandler: 4(SP) should be _type+0(FP) runtime/sys_windows_386.s: [386] setldt: function setldt missing Go declaration -runtime/zcallback_windows.s: [386] callbackasm: function callbackasm missing Go declaration runtime/sys_windows_386.s: [386] callbackasm1+0: function callbackasm1+0 missing Go declaration runtime/sys_windows_386.s: [386] tstart: function tstart missing Go declaration runtime/sys_windows_386.s: [386] tstart_stdcall: RET without writing to 4-byte ret+4(FP) diff --git a/src/cmd/vet/all/whitelist/windows_amd64.txt b/src/cmd/vet/all/whitelist/windows_amd64.txt index 3be4602579..676e6baf71 100644 --- a/src/cmd/vet/all/whitelist/windows_amd64.txt +++ b/src/cmd/vet/all/whitelist/windows_amd64.txt @@ -6,4 +6,3 @@ runtime/sys_windows_amd64.s: [amd64] callbackasm1: function callbackasm1 missing runtime/sys_windows_amd64.s: [amd64] tstart_stdcall: RET without writing to 4-byte ret+8(FP) runtime/sys_windows_amd64.s: [amd64] settls: function settls missing Go declaration runtime/sys_windows_amd64.s: [amd64] cannot check cross-package assembly function: now is in package time -runtime/zcallback_windows.s: [amd64] callbackasm: function callbackasm missing Go declaration diff --git a/src/cmd/vet/main.go b/src/cmd/vet/main.go index c50d4885a0..6e885121c8 100644 --- a/src/cmd/vet/main.go +++ b/src/cmd/vet/main.go @@ -273,7 +273,7 @@ func main() { // Accept space-separated tags because that matches // the go command's other subcommands. // Accept commas because go tool vet traditionally has. - tagList = strings.Fields(strings.Replace(*tags, ",", " ", -1)) + tagList = strings.Fields(strings.ReplaceAll(*tags, ",", " ")) initPrintFlags() initUnusedFlags() @@ -467,6 +467,7 @@ type Package struct { path string defs map[*ast.Ident]types.Object uses map[*ast.Ident]types.Object + implicits map[ast.Node]types.Object selectors map[*ast.SelectorExpr]*types.Selection types map[ast.Expr]types.TypeAndValue spans map[types.Object]Span diff --git a/src/cmd/vet/shadow.go b/src/cmd/vet/shadow.go index 29c952fd88..47a48834bf 100644 --- a/src/cmd/vet/shadow.go +++ b/src/cmd/vet/shadow.go @@ -86,14 +86,11 @@ func (s Span) contains(pos token.Pos) bool { return s.min <= pos && pos < s.max } -// growSpan expands the span for the object to contain the instance represented -// by the identifier. -func (pkg *Package) growSpan(ident *ast.Ident, obj types.Object) { +// growSpan expands the span for the object to contain the source range [pos, end). +func (pkg *Package) growSpan(obj types.Object, pos, end token.Pos) { if *strictShadowing { return // No need } - pos := ident.Pos() - end := ident.End() span, ok := pkg.spans[obj] if ok { if span.min > pos { @@ -232,7 +229,7 @@ func checkShadowing(f *File, ident *ast.Ident) { // the shadowing identifier. span, ok := f.pkg.spans[shadowed] if !ok { - f.Badf(ident.Pos(), "internal error: no range for %q", ident.Name) + f.Badf(shadowed.Pos(), "internal error: no range for %q", shadowed.Name()) return } if !span.contains(ident.Pos()) { diff --git a/src/cmd/vet/testdata/shadow.go b/src/cmd/vet/testdata/shadow.go index c55cb2772a..d10fde2b81 100644 --- a/src/cmd/vet/testdata/shadow.go +++ b/src/cmd/vet/testdata/shadow.go @@ -57,3 +57,35 @@ func ShadowRead(f *os.File, buf []byte) (err error) { func one() int { return 1 } + +// Must not complain with an internal error for the +// implicitly declared type switch variable v. +func issue26725(x interface{}) int { + switch v := x.(type) { + case int, int32: + if v, ok := x.(int); ok { + return v + } + case int64: + return int(v) + } + return 0 +} + +// Verify that implicitly declared variables from +// type switches are considered in shadowing analysis. +func shadowTypeSwitch(a interface{}) { + switch t := a.(type) { + case int: + { + t := 0 // ERROR "declaration of .t. shadows declaration at shadow.go:78" + _ = t + } + _ = t + case uint: + { + t := uint(0) // OK because t is not mentioned later in this function + _ = t + } + } +} diff --git a/src/cmd/vet/types.go b/src/cmd/vet/types.go index 5f8e481e01..3ff4b5966d 100644 --- a/src/cmd/vet/types.go +++ b/src/cmd/vet/types.go @@ -73,6 +73,7 @@ func (pkg *Package) check(fs *token.FileSet, astFiles []*ast.File) []error { } pkg.defs = make(map[*ast.Ident]types.Object) pkg.uses = make(map[*ast.Ident]types.Object) + pkg.implicits = make(map[ast.Node]types.Object) pkg.selectors = make(map[*ast.SelectorExpr]*types.Selection) pkg.spans = make(map[types.Object]Span) pkg.types = make(map[ast.Expr]types.TypeAndValue) @@ -95,6 +96,7 @@ func (pkg *Package) check(fs *token.FileSet, astFiles []*ast.File) []error { Types: pkg.types, Defs: pkg.defs, Uses: pkg.uses, + Implicits: pkg.implicits, } typesPkg, err := config.Check(pkg.path, fs, astFiles, info) if len(allErrors) == 0 && err != nil { @@ -103,10 +105,28 @@ func (pkg *Package) check(fs *token.FileSet, astFiles []*ast.File) []error { pkg.typesPkg = typesPkg // update spans for id, obj := range pkg.defs { - pkg.growSpan(id, obj) + // Ignore identifiers that don't denote objects + // (package names, symbolic variables such as t + // in t := x.(type) of type switch headers). + if obj != nil { + pkg.growSpan(obj, id.Pos(), id.End()) + } } for id, obj := range pkg.uses { - pkg.growSpan(id, obj) + pkg.growSpan(obj, id.Pos(), id.End()) + } + for node, obj := range pkg.implicits { + // A type switch with a short variable declaration + // such as t := x.(type) doesn't declare the symbolic + // variable (t in the example) at the switch header; + // instead a new variable t (with specific type) is + // declared implicitly for each case. Such variables + // are found in the types.Info.Implicits (not Defs) + // map. Add them here, assuming they are declared at + // the type cases' colon ":". + if cc, ok := node.(*ast.CaseClause); ok { + pkg.growSpan(obj, cc.Colon, cc.Colon) + } } return allErrors } diff --git a/src/cmd/vet/vet_test.go b/src/cmd/vet/vet_test.go index 90665d77bc..df84d6cc98 100644 --- a/src/cmd/vet/vet_test.go +++ b/src/cmd/vet/vet_test.go @@ -243,7 +243,7 @@ func errorCheck(outStr string, wantAuto bool, fullshort ...string) (err error) { for i := range out { for j := 0; j < len(fullshort); j += 2 { full, short := fullshort[j], fullshort[j+1] - out[i] = strings.Replace(out[i], full, short, -1) + out[i] = strings.ReplaceAll(out[i], full, short) } } diff --git a/src/compress/bzip2/bzip2_test.go b/src/compress/bzip2/bzip2_test.go index 3848603e0d..c432bb5226 100644 --- a/src/compress/bzip2/bzip2_test.go +++ b/src/compress/bzip2/bzip2_test.go @@ -214,7 +214,7 @@ func TestZeroRead(t *testing.T) { var ( digits = mustLoadFile("testdata/e.txt.bz2") - twain = mustLoadFile("testdata/Mark.Twain-Tom.Sawyer.txt.bz2") + newton = mustLoadFile("testdata/Isaac.Newton-Opticks.txt.bz2") random = mustLoadFile("testdata/random.data.bz2") ) @@ -236,5 +236,5 @@ func benchmarkDecode(b *testing.B, compressed []byte) { } func BenchmarkDecodeDigits(b *testing.B) { benchmarkDecode(b, digits) } -func BenchmarkDecodeTwain(b *testing.B) { benchmarkDecode(b, twain) } +func BenchmarkDecodeNewton(b *testing.B) { benchmarkDecode(b, newton) } func BenchmarkDecodeRand(b *testing.B) { benchmarkDecode(b, random) } diff --git a/src/compress/bzip2/testdata/Isaac.Newton-Opticks.txt.bz2 b/src/compress/bzip2/testdata/Isaac.Newton-Opticks.txt.bz2 Binary files differnew file mode 100644 index 0000000000..6c56de3bc2 --- /dev/null +++ b/src/compress/bzip2/testdata/Isaac.Newton-Opticks.txt.bz2 diff --git a/src/compress/bzip2/testdata/Mark.Twain-Tom.Sawyer.txt.bz2 b/src/compress/bzip2/testdata/Mark.Twain-Tom.Sawyer.txt.bz2 Binary files differdeleted file mode 100644 index eac2b0571b..0000000000 --- a/src/compress/bzip2/testdata/Mark.Twain-Tom.Sawyer.txt.bz2 +++ /dev/null diff --git a/src/compress/flate/deflate_test.go b/src/compress/flate/deflate_test.go index fbea761721..831be2198c 100644 --- a/src/compress/flate/deflate_test.go +++ b/src/compress/flate/deflate_test.go @@ -371,9 +371,9 @@ var deflateInflateStringTests = []deflateInflateStringTest{ [...]int{100018, 50650, 50960, 51150, 50930, 50790, 50790, 50790, 50790, 50790, 43683}, }, { - "../testdata/Mark.Twain-Tom.Sawyer.txt", - "Mark.Twain-Tom.Sawyer", - [...]int{407330, 187598, 180361, 172974, 169160, 163476, 160936, 160506, 160295, 160295, 233460}, + "../../testdata/Isaac.Newton-Opticks.txt", + "Isaac.Newton-Opticks", + [...]int{567248, 218338, 198211, 193152, 181100, 175427, 175427, 173597, 173422, 173422, 325240}, }, } @@ -654,7 +654,7 @@ func (w *failWriter) Write(b []byte) (int, error) { func TestWriterPersistentError(t *testing.T) { t.Parallel() - d, err := ioutil.ReadFile("../testdata/Mark.Twain-Tom.Sawyer.txt") + d, err := ioutil.ReadFile("../../testdata/Isaac.Newton-Opticks.txt") if err != nil { t.Fatalf("ReadFile: %v", err) } diff --git a/src/compress/flate/reader_test.go b/src/compress/flate/reader_test.go index b0a16ce18b..9d2943a540 100644 --- a/src/compress/flate/reader_test.go +++ b/src/compress/flate/reader_test.go @@ -27,8 +27,8 @@ var suites = []struct{ name, file string }{ // does not repeat, but there are only 10 possible digits, so it should be // reasonably compressible. {"Digits", "../testdata/e.txt"}, - // Twain is Mark Twain's classic English novel. - {"Twain", "../testdata/Mark.Twain-Tom.Sawyer.txt"}, + // Newton is Isaac Newtons's educational text on Opticks. + {"Newton", "../../testdata/Isaac.Newton-Opticks.txt"}, } func BenchmarkDecode(b *testing.B) { diff --git a/src/compress/testdata/Mark.Twain-Tom.Sawyer.txt b/src/compress/testdata/Mark.Twain-Tom.Sawyer.txt deleted file mode 100644 index c9106fd522..0000000000 --- a/src/compress/testdata/Mark.Twain-Tom.Sawyer.txt +++ /dev/null @@ -1,8465 +0,0 @@ -Produced by David Widger. The previous edition was updated by Jose -Menendez. - - - - - - THE ADVENTURES OF TOM SAWYER - BY - MARK TWAIN - (Samuel Langhorne Clemens) - - - - - P R E F A C E - -MOST of the adventures recorded in this book really occurred; one or -two were experiences of my own, the rest those of boys who were -schoolmates of mine. Huck Finn is drawn from life; Tom Sawyer also, but -not from an individual--he is a combination of the characteristics of -three boys whom I knew, and therefore belongs to the composite order of -architecture. - -The odd superstitions touched upon were all prevalent among children -and slaves in the West at the period of this story--that is to say, -thirty or forty years ago. - -Although my book is intended mainly for the entertainment of boys and -girls, I hope it will not be shunned by men and women on that account, -for part of my plan has been to try to pleasantly remind adults of what -they once were themselves, and of how they felt and thought and talked, -and what queer enterprises they sometimes engaged in. - - THE AUTHOR. - -HARTFORD, 1876. - - - - T O M S A W Y E R - - - -CHAPTER I - -"TOM!" - -No answer. - -"TOM!" - -No answer. - -"What's gone with that boy, I wonder? You TOM!" - -No answer. - -The old lady pulled her spectacles down and looked over them about the -room; then she put them up and looked out under them. She seldom or -never looked THROUGH them for so small a thing as a boy; they were her -state pair, the pride of her heart, and were built for "style," not -service--she could have seen through a pair of stove-lids just as well. -She looked perplexed for a moment, and then said, not fiercely, but -still loud enough for the furniture to hear: - -"Well, I lay if I get hold of you I'll--" - -She did not finish, for by this time she was bending down and punching -under the bed with the broom, and so she needed breath to punctuate the -punches with. She resurrected nothing but the cat. - -"I never did see the beat of that boy!" - -She went to the open door and stood in it and looked out among the -tomato vines and "jimpson" weeds that constituted the garden. No Tom. -So she lifted up her voice at an angle calculated for distance and -shouted: - -"Y-o-u-u TOM!" - -There was a slight noise behind her and she turned just in time to -seize a small boy by the slack of his roundabout and arrest his flight. - -"There! I might 'a' thought of that closet. What you been doing in -there?" - -"Nothing." - -"Nothing! Look at your hands. And look at your mouth. What IS that -truck?" - -"I don't know, aunt." - -"Well, I know. It's jam--that's what it is. Forty times I've said if -you didn't let that jam alone I'd skin you. Hand me that switch." - -The switch hovered in the air--the peril was desperate-- - -"My! Look behind you, aunt!" - -The old lady whirled round, and snatched her skirts out of danger. The -lad fled on the instant, scrambled up the high board-fence, and -disappeared over it. - -His aunt Polly stood surprised a moment, and then broke into a gentle -laugh. - -"Hang the boy, can't I never learn anything? Ain't he played me tricks -enough like that for me to be looking out for him by this time? But old -fools is the biggest fools there is. Can't learn an old dog new tricks, -as the saying is. But my goodness, he never plays them alike, two days, -and how is a body to know what's coming? He 'pears to know just how -long he can torment me before I get my dander up, and he knows if he -can make out to put me off for a minute or make me laugh, it's all down -again and I can't hit him a lick. I ain't doing my duty by that boy, -and that's the Lord's truth, goodness knows. Spare the rod and spile -the child, as the Good Book says. I'm a laying up sin and suffering for -us both, I know. He's full of the Old Scratch, but laws-a-me! he's my -own dead sister's boy, poor thing, and I ain't got the heart to lash -him, somehow. Every time I let him off, my conscience does hurt me so, -and every time I hit him my old heart most breaks. Well-a-well, man -that is born of woman is of few days and full of trouble, as the -Scripture says, and I reckon it's so. He'll play hookey this evening, * -and [* Southwestern for "afternoon"] I'll just be obleeged to make him -work, to-morrow, to punish him. It's mighty hard to make him work -Saturdays, when all the boys is having holiday, but he hates work more -than he hates anything else, and I've GOT to do some of my duty by him, -or I'll be the ruination of the child." - -Tom did play hookey, and he had a very good time. He got back home -barely in season to help Jim, the small colored boy, saw next-day's -wood and split the kindlings before supper--at least he was there in -time to tell his adventures to Jim while Jim did three-fourths of the -work. Tom's younger brother (or rather half-brother) Sid was already -through with his part of the work (picking up chips), for he was a -quiet boy, and had no adventurous, troublesome ways. - -While Tom was eating his supper, and stealing sugar as opportunity -offered, Aunt Polly asked him questions that were full of guile, and -very deep--for she wanted to trap him into damaging revealments. Like -many other simple-hearted souls, it was her pet vanity to believe she -was endowed with a talent for dark and mysterious diplomacy, and she -loved to contemplate her most transparent devices as marvels of low -cunning. Said she: - -"Tom, it was middling warm in school, warn't it?" - -"Yes'm." - -"Powerful warm, warn't it?" - -"Yes'm." - -"Didn't you want to go in a-swimming, Tom?" - -A bit of a scare shot through Tom--a touch of uncomfortable suspicion. -He searched Aunt Polly's face, but it told him nothing. So he said: - -"No'm--well, not very much." - -The old lady reached out her hand and felt Tom's shirt, and said: - -"But you ain't too warm now, though." And it flattered her to reflect -that she had discovered that the shirt was dry without anybody knowing -that that was what she had in her mind. But in spite of her, Tom knew -where the wind lay, now. So he forestalled what might be the next move: - -"Some of us pumped on our heads--mine's damp yet. See?" - -Aunt Polly was vexed to think she had overlooked that bit of -circumstantial evidence, and missed a trick. Then she had a new -inspiration: - -"Tom, you didn't have to undo your shirt collar where I sewed it, to -pump on your head, did you? Unbutton your jacket!" - -The trouble vanished out of Tom's face. He opened his jacket. His -shirt collar was securely sewed. - -"Bother! Well, go 'long with you. I'd made sure you'd played hookey -and been a-swimming. But I forgive ye, Tom. I reckon you're a kind of a -singed cat, as the saying is--better'n you look. THIS time." - -She was half sorry her sagacity had miscarried, and half glad that Tom -had stumbled into obedient conduct for once. - -But Sidney said: - -"Well, now, if I didn't think you sewed his collar with white thread, -but it's black." - -"Why, I did sew it with white! Tom!" - -But Tom did not wait for the rest. As he went out at the door he said: - -"Siddy, I'll lick you for that." - -In a safe place Tom examined two large needles which were thrust into -the lapels of his jacket, and had thread bound about them--one needle -carried white thread and the other black. He said: - -"She'd never noticed if it hadn't been for Sid. Confound it! sometimes -she sews it with white, and sometimes she sews it with black. I wish to -geeminy she'd stick to one or t'other--I can't keep the run of 'em. But -I bet you I'll lam Sid for that. I'll learn him!" - -He was not the Model Boy of the village. He knew the model boy very -well though--and loathed him. - -Within two minutes, or even less, he had forgotten all his troubles. -Not because his troubles were one whit less heavy and bitter to him -than a man's are to a man, but because a new and powerful interest bore -them down and drove them out of his mind for the time--just as men's -misfortunes are forgotten in the excitement of new enterprises. This -new interest was a valued novelty in whistling, which he had just -acquired from a negro, and he was suffering to practise it undisturbed. -It consisted in a peculiar bird-like turn, a sort of liquid warble, -produced by touching the tongue to the roof of the mouth at short -intervals in the midst of the music--the reader probably remembers how -to do it, if he has ever been a boy. Diligence and attention soon gave -him the knack of it, and he strode down the street with his mouth full -of harmony and his soul full of gratitude. He felt much as an -astronomer feels who has discovered a new planet--no doubt, as far as -strong, deep, unalloyed pleasure is concerned, the advantage was with -the boy, not the astronomer. - -The summer evenings were long. It was not dark, yet. Presently Tom -checked his whistle. A stranger was before him--a boy a shade larger -than himself. A new-comer of any age or either sex was an impressive -curiosity in the poor little shabby village of St. Petersburg. This boy -was well dressed, too--well dressed on a week-day. This was simply -astounding. His cap was a dainty thing, his close-buttoned blue cloth -roundabout was new and natty, and so were his pantaloons. He had shoes -on--and it was only Friday. He even wore a necktie, a bright bit of -ribbon. He had a citified air about him that ate into Tom's vitals. The -more Tom stared at the splendid marvel, the higher he turned up his -nose at his finery and the shabbier and shabbier his own outfit seemed -to him to grow. Neither boy spoke. If one moved, the other moved--but -only sidewise, in a circle; they kept face to face and eye to eye all -the time. Finally Tom said: - -"I can lick you!" - -"I'd like to see you try it." - -"Well, I can do it." - -"No you can't, either." - -"Yes I can." - -"No you can't." - -"I can." - -"You can't." - -"Can!" - -"Can't!" - -An uncomfortable pause. Then Tom said: - -"What's your name?" - -"'Tisn't any of your business, maybe." - -"Well I 'low I'll MAKE it my business." - -"Well why don't you?" - -"If you say much, I will." - -"Much--much--MUCH. There now." - -"Oh, you think you're mighty smart, DON'T you? I could lick you with -one hand tied behind me, if I wanted to." - -"Well why don't you DO it? You SAY you can do it." - -"Well I WILL, if you fool with me." - -"Oh yes--I've seen whole families in the same fix." - -"Smarty! You think you're SOME, now, DON'T you? Oh, what a hat!" - -"You can lump that hat if you don't like it. I dare you to knock it -off--and anybody that'll take a dare will suck eggs." - -"You're a liar!" - -"You're another." - -"You're a fighting liar and dasn't take it up." - -"Aw--take a walk!" - -"Say--if you give me much more of your sass I'll take and bounce a -rock off'n your head." - -"Oh, of COURSE you will." - -"Well I WILL." - -"Well why don't you DO it then? What do you keep SAYING you will for? -Why don't you DO it? It's because you're afraid." - -"I AIN'T afraid." - -"You are." - -"I ain't." - -"You are." - -Another pause, and more eying and sidling around each other. Presently -they were shoulder to shoulder. Tom said: - -"Get away from here!" - -"Go away yourself!" - -"I won't." - -"I won't either." - -So they stood, each with a foot placed at an angle as a brace, and -both shoving with might and main, and glowering at each other with -hate. But neither could get an advantage. After struggling till both -were hot and flushed, each relaxed his strain with watchful caution, -and Tom said: - -"You're a coward and a pup. I'll tell my big brother on you, and he -can thrash you with his little finger, and I'll make him do it, too." - -"What do I care for your big brother? I've got a brother that's bigger -than he is--and what's more, he can throw him over that fence, too." -[Both brothers were imaginary.] - -"That's a lie." - -"YOUR saying so don't make it so." - -Tom drew a line in the dust with his big toe, and said: - -"I dare you to step over that, and I'll lick you till you can't stand -up. Anybody that'll take a dare will steal sheep." - -The new boy stepped over promptly, and said: - -"Now you said you'd do it, now let's see you do it." - -"Don't you crowd me now; you better look out." - -"Well, you SAID you'd do it--why don't you do it?" - -"By jingo! for two cents I WILL do it." - -The new boy took two broad coppers out of his pocket and held them out -with derision. Tom struck them to the ground. In an instant both boys -were rolling and tumbling in the dirt, gripped together like cats; and -for the space of a minute they tugged and tore at each other's hair and -clothes, punched and scratched each other's nose, and covered -themselves with dust and glory. Presently the confusion took form, and -through the fog of battle Tom appeared, seated astride the new boy, and -pounding him with his fists. "Holler 'nuff!" said he. - -The boy only struggled to free himself. He was crying--mainly from rage. - -"Holler 'nuff!"--and the pounding went on. - -At last the stranger got out a smothered "'Nuff!" and Tom let him up -and said: - -"Now that'll learn you. Better look out who you're fooling with next -time." - -The new boy went off brushing the dust from his clothes, sobbing, -snuffling, and occasionally looking back and shaking his head and -threatening what he would do to Tom the "next time he caught him out." -To which Tom responded with jeers, and started off in high feather, and -as soon as his back was turned the new boy snatched up a stone, threw -it and hit him between the shoulders and then turned tail and ran like -an antelope. Tom chased the traitor home, and thus found out where he -lived. He then held a position at the gate for some time, daring the -enemy to come outside, but the enemy only made faces at him through the -window and declined. At last the enemy's mother appeared, and called -Tom a bad, vicious, vulgar child, and ordered him away. So he went -away; but he said he "'lowed" to "lay" for that boy. - -He got home pretty late that night, and when he climbed cautiously in -at the window, he uncovered an ambuscade, in the person of his aunt; -and when she saw the state his clothes were in her resolution to turn -his Saturday holiday into captivity at hard labor became adamantine in -its firmness. - - - -CHAPTER II - -SATURDAY morning was come, and all the summer world was bright and -fresh, and brimming with life. There was a song in every heart; and if -the heart was young the music issued at the lips. There was cheer in -every face and a spring in every step. The locust-trees were in bloom -and the fragrance of the blossoms filled the air. Cardiff Hill, beyond -the village and above it, was green with vegetation and it lay just far -enough away to seem a Delectable Land, dreamy, reposeful, and inviting. - -Tom appeared on the sidewalk with a bucket of whitewash and a -long-handled brush. He surveyed the fence, and all gladness left him and -a deep melancholy settled down upon his spirit. Thirty yards of board -fence nine feet high. Life to him seemed hollow, and existence but a -burden. Sighing, he dipped his brush and passed it along the topmost -plank; repeated the operation; did it again; compared the insignificant -whitewashed streak with the far-reaching continent of unwhitewashed -fence, and sat down on a tree-box discouraged. Jim came skipping out at -the gate with a tin pail, and singing Buffalo Gals. Bringing water from -the town pump had always been hateful work in Tom's eyes, before, but -now it did not strike him so. He remembered that there was company at -the pump. White, mulatto, and negro boys and girls were always there -waiting their turns, resting, trading playthings, quarrelling, -fighting, skylarking. And he remembered that although the pump was only -a hundred and fifty yards off, Jim never got back with a bucket of -water under an hour--and even then somebody generally had to go after -him. Tom said: - -"Say, Jim, I'll fetch the water if you'll whitewash some." - -Jim shook his head and said: - -"Can't, Mars Tom. Ole missis, she tole me I got to go an' git dis -water an' not stop foolin' roun' wid anybody. She say she spec' Mars -Tom gwine to ax me to whitewash, an' so she tole me go 'long an' 'tend -to my own business--she 'lowed SHE'D 'tend to de whitewashin'." - -"Oh, never you mind what she said, Jim. That's the way she always -talks. Gimme the bucket--I won't be gone only a a minute. SHE won't -ever know." - -"Oh, I dasn't, Mars Tom. Ole missis she'd take an' tar de head off'n -me. 'Deed she would." - -"SHE! She never licks anybody--whacks 'em over the head with her -thimble--and who cares for that, I'd like to know. She talks awful, but -talk don't hurt--anyways it don't if she don't cry. Jim, I'll give you -a marvel. I'll give you a white alley!" - -Jim began to waver. - -"White alley, Jim! And it's a bully taw." - -"My! Dat's a mighty gay marvel, I tell you! But Mars Tom I's powerful -'fraid ole missis--" - -"And besides, if you will I'll show you my sore toe." - -Jim was only human--this attraction was too much for him. He put down -his pail, took the white alley, and bent over the toe with absorbing -interest while the bandage was being unwound. In another moment he was -flying down the street with his pail and a tingling rear, Tom was -whitewashing with vigor, and Aunt Polly was retiring from the field -with a slipper in her hand and triumph in her eye. - -But Tom's energy did not last. He began to think of the fun he had -planned for this day, and his sorrows multiplied. Soon the free boys -would come tripping along on all sorts of delicious expeditions, and -they would make a world of fun of him for having to work--the very -thought of it burnt him like fire. He got out his worldly wealth and -examined it--bits of toys, marbles, and trash; enough to buy an -exchange of WORK, maybe, but not half enough to buy so much as half an -hour of pure freedom. So he returned his straitened means to his -pocket, and gave up the idea of trying to buy the boys. At this dark -and hopeless moment an inspiration burst upon him! Nothing less than a -great, magnificent inspiration. - -He took up his brush and went tranquilly to work. Ben Rogers hove in -sight presently--the very boy, of all boys, whose ridicule he had been -dreading. Ben's gait was the hop-skip-and-jump--proof enough that his -heart was light and his anticipations high. He was eating an apple, and -giving a long, melodious whoop, at intervals, followed by a deep-toned -ding-dong-dong, ding-dong-dong, for he was personating a steamboat. As -he drew near, he slackened speed, took the middle of the street, leaned -far over to starboard and rounded to ponderously and with laborious -pomp and circumstance--for he was personating the Big Missouri, and -considered himself to be drawing nine feet of water. He was boat and -captain and engine-bells combined, so he had to imagine himself -standing on his own hurricane-deck giving the orders and executing them: - -"Stop her, sir! Ting-a-ling-ling!" The headway ran almost out, and he -drew up slowly toward the sidewalk. - -"Ship up to back! Ting-a-ling-ling!" His arms straightened and -stiffened down his sides. - -"Set her back on the stabboard! Ting-a-ling-ling! Chow! ch-chow-wow! -Chow!" His right hand, meantime, describing stately circles--for it was -representing a forty-foot wheel. - -"Let her go back on the labboard! Ting-a-lingling! Chow-ch-chow-chow!" -The left hand began to describe circles. - -"Stop the stabboard! Ting-a-ling-ling! Stop the labboard! Come ahead -on the stabboard! Stop her! Let your outside turn over slow! -Ting-a-ling-ling! Chow-ow-ow! Get out that head-line! LIVELY now! -Come--out with your spring-line--what're you about there! Take a turn -round that stump with the bight of it! Stand by that stage, now--let her -go! Done with the engines, sir! Ting-a-ling-ling! SH'T! S'H'T! SH'T!" -(trying the gauge-cocks). - -Tom went on whitewashing--paid no attention to the steamboat. Ben -stared a moment and then said: "Hi-YI! YOU'RE up a stump, ain't you!" - -No answer. Tom surveyed his last touch with the eye of an artist, then -he gave his brush another gentle sweep and surveyed the result, as -before. Ben ranged up alongside of him. Tom's mouth watered for the -apple, but he stuck to his work. Ben said: - -"Hello, old chap, you got to work, hey?" - -Tom wheeled suddenly and said: - -"Why, it's you, Ben! I warn't noticing." - -"Say--I'm going in a-swimming, I am. Don't you wish you could? But of -course you'd druther WORK--wouldn't you? Course you would!" - -Tom contemplated the boy a bit, and said: - -"What do you call work?" - -"Why, ain't THAT work?" - -Tom resumed his whitewashing, and answered carelessly: - -"Well, maybe it is, and maybe it ain't. All I know, is, it suits Tom -Sawyer." - -"Oh come, now, you don't mean to let on that you LIKE it?" - -The brush continued to move. - -"Like it? Well, I don't see why I oughtn't to like it. Does a boy get -a chance to whitewash a fence every day?" - -That put the thing in a new light. Ben stopped nibbling his apple. Tom -swept his brush daintily back and forth--stepped back to note the -effect--added a touch here and there--criticised the effect again--Ben -watching every move and getting more and more interested, more and more -absorbed. Presently he said: - -"Say, Tom, let ME whitewash a little." - -Tom considered, was about to consent; but he altered his mind: - -"No--no--I reckon it wouldn't hardly do, Ben. You see, Aunt Polly's -awful particular about this fence--right here on the street, you know ---but if it was the back fence I wouldn't mind and SHE wouldn't. Yes, -she's awful particular about this fence; it's got to be done very -careful; I reckon there ain't one boy in a thousand, maybe two -thousand, that can do it the way it's got to be done." - -"No--is that so? Oh come, now--lemme just try. Only just a little--I'd -let YOU, if you was me, Tom." - -"Ben, I'd like to, honest injun; but Aunt Polly--well, Jim wanted to -do it, but she wouldn't let him; Sid wanted to do it, and she wouldn't -let Sid. Now don't you see how I'm fixed? If you was to tackle this -fence and anything was to happen to it--" - -"Oh, shucks, I'll be just as careful. Now lemme try. Say--I'll give -you the core of my apple." - -"Well, here--No, Ben, now don't. I'm afeard--" - -"I'll give you ALL of it!" - -Tom gave up the brush with reluctance in his face, but alacrity in his -heart. And while the late steamer Big Missouri worked and sweated in -the sun, the retired artist sat on a barrel in the shade close by, -dangled his legs, munched his apple, and planned the slaughter of more -innocents. There was no lack of material; boys happened along every -little while; they came to jeer, but remained to whitewash. By the time -Ben was fagged out, Tom had traded the next chance to Billy Fisher for -a kite, in good repair; and when he played out, Johnny Miller bought in -for a dead rat and a string to swing it with--and so on, and so on, -hour after hour. And when the middle of the afternoon came, from being -a poor poverty-stricken boy in the morning, Tom was literally rolling -in wealth. He had besides the things before mentioned, twelve marbles, -part of a jews-harp, a piece of blue bottle-glass to look through, a -spool cannon, a key that wouldn't unlock anything, a fragment of chalk, -a glass stopper of a decanter, a tin soldier, a couple of tadpoles, six -fire-crackers, a kitten with only one eye, a brass doorknob, a -dog-collar--but no dog--the handle of a knife, four pieces of -orange-peel, and a dilapidated old window sash. - -He had had a nice, good, idle time all the while--plenty of company ---and the fence had three coats of whitewash on it! If he hadn't run out -of whitewash he would have bankrupted every boy in the village. - -Tom said to himself that it was not such a hollow world, after all. He -had discovered a great law of human action, without knowing it--namely, -that in order to make a man or a boy covet a thing, it is only -necessary to make the thing difficult to attain. If he had been a great -and wise philosopher, like the writer of this book, he would now have -comprehended that Work consists of whatever a body is OBLIGED to do, -and that Play consists of whatever a body is not obliged to do. And -this would help him to understand why constructing artificial flowers -or performing on a tread-mill is work, while rolling ten-pins or -climbing Mont Blanc is only amusement. There are wealthy gentlemen in -England who drive four-horse passenger-coaches twenty or thirty miles -on a daily line, in the summer, because the privilege costs them -considerable money; but if they were offered wages for the service, -that would turn it into work and then they would resign. - -The boy mused awhile over the substantial change which had taken place -in his worldly circumstances, and then wended toward headquarters to -report. - - - -CHAPTER III - -TOM presented himself before Aunt Polly, who was sitting by an open -window in a pleasant rearward apartment, which was bedroom, -breakfast-room, dining-room, and library, combined. The balmy summer -air, the restful quiet, the odor of the flowers, and the drowsing murmur -of the bees had had their effect, and she was nodding over her knitting ---for she had no company but the cat, and it was asleep in her lap. Her -spectacles were propped up on her gray head for safety. She had thought -that of course Tom had deserted long ago, and she wondered at seeing him -place himself in her power again in this intrepid way. He said: "Mayn't -I go and play now, aunt?" - -"What, a'ready? How much have you done?" - -"It's all done, aunt." - -"Tom, don't lie to me--I can't bear it." - -"I ain't, aunt; it IS all done." - -Aunt Polly placed small trust in such evidence. She went out to see -for herself; and she would have been content to find twenty per cent. -of Tom's statement true. When she found the entire fence whitewashed, -and not only whitewashed but elaborately coated and recoated, and even -a streak added to the ground, her astonishment was almost unspeakable. -She said: - -"Well, I never! There's no getting round it, you can work when you're -a mind to, Tom." And then she diluted the compliment by adding, "But -it's powerful seldom you're a mind to, I'm bound to say. Well, go 'long -and play; but mind you get back some time in a week, or I'll tan you." - -She was so overcome by the splendor of his achievement that she took -him into the closet and selected a choice apple and delivered it to -him, along with an improving lecture upon the added value and flavor a -treat took to itself when it came without sin through virtuous effort. -And while she closed with a happy Scriptural flourish, he "hooked" a -doughnut. - -Then he skipped out, and saw Sid just starting up the outside stairway -that led to the back rooms on the second floor. Clods were handy and -the air was full of them in a twinkling. They raged around Sid like a -hail-storm; and before Aunt Polly could collect her surprised faculties -and sally to the rescue, six or seven clods had taken personal effect, -and Tom was over the fence and gone. There was a gate, but as a general -thing he was too crowded for time to make use of it. His soul was at -peace, now that he had settled with Sid for calling attention to his -black thread and getting him into trouble. - -Tom skirted the block, and came round into a muddy alley that led by -the back of his aunt's cow-stable. He presently got safely beyond the -reach of capture and punishment, and hastened toward the public square -of the village, where two "military" companies of boys had met for -conflict, according to previous appointment. Tom was General of one of -these armies, Joe Harper (a bosom friend) General of the other. These -two great commanders did not condescend to fight in person--that being -better suited to the still smaller fry--but sat together on an eminence -and conducted the field operations by orders delivered through -aides-de-camp. Tom's army won a great victory, after a long and -hard-fought battle. Then the dead were counted, prisoners exchanged, -the terms of the next disagreement agreed upon, and the day for the -necessary battle appointed; after which the armies fell into line and -marched away, and Tom turned homeward alone. - -As he was passing by the house where Jeff Thatcher lived, he saw a new -girl in the garden--a lovely little blue-eyed creature with yellow hair -plaited into two long-tails, white summer frock and embroidered -pantalettes. The fresh-crowned hero fell without firing a shot. A -certain Amy Lawrence vanished out of his heart and left not even a -memory of herself behind. He had thought he loved her to distraction; -he had regarded his passion as adoration; and behold it was only a poor -little evanescent partiality. He had been months winning her; she had -confessed hardly a week ago; he had been the happiest and the proudest -boy in the world only seven short days, and here in one instant of time -she had gone out of his heart like a casual stranger whose visit is -done. - -He worshipped this new angel with furtive eye, till he saw that she -had discovered him; then he pretended he did not know she was present, -and began to "show off" in all sorts of absurd boyish ways, in order to -win her admiration. He kept up this grotesque foolishness for some -time; but by-and-by, while he was in the midst of some dangerous -gymnastic performances, he glanced aside and saw that the little girl -was wending her way toward the house. Tom came up to the fence and -leaned on it, grieving, and hoping she would tarry yet awhile longer. -She halted a moment on the steps and then moved toward the door. Tom -heaved a great sigh as she put her foot on the threshold. But his face -lit up, right away, for she tossed a pansy over the fence a moment -before she disappeared. - -The boy ran around and stopped within a foot or two of the flower, and -then shaded his eyes with his hand and began to look down street as if -he had discovered something of interest going on in that direction. -Presently he picked up a straw and began trying to balance it on his -nose, with his head tilted far back; and as he moved from side to side, -in his efforts, he edged nearer and nearer toward the pansy; finally -his bare foot rested upon it, his pliant toes closed upon it, and he -hopped away with the treasure and disappeared round the corner. But -only for a minute--only while he could button the flower inside his -jacket, next his heart--or next his stomach, possibly, for he was not -much posted in anatomy, and not hypercritical, anyway. - -He returned, now, and hung about the fence till nightfall, "showing -off," as before; but the girl never exhibited herself again, though Tom -comforted himself a little with the hope that she had been near some -window, meantime, and been aware of his attentions. Finally he strode -home reluctantly, with his poor head full of visions. - -All through supper his spirits were so high that his aunt wondered -"what had got into the child." He took a good scolding about clodding -Sid, and did not seem to mind it in the least. He tried to steal sugar -under his aunt's very nose, and got his knuckles rapped for it. He said: - -"Aunt, you don't whack Sid when he takes it." - -"Well, Sid don't torment a body the way you do. You'd be always into -that sugar if I warn't watching you." - -Presently she stepped into the kitchen, and Sid, happy in his -immunity, reached for the sugar-bowl--a sort of glorying over Tom which -was wellnigh unbearable. But Sid's fingers slipped and the bowl dropped -and broke. Tom was in ecstasies. In such ecstasies that he even -controlled his tongue and was silent. He said to himself that he would -not speak a word, even when his aunt came in, but would sit perfectly -still till she asked who did the mischief; and then he would tell, and -there would be nothing so good in the world as to see that pet model -"catch it." He was so brimful of exultation that he could hardly hold -himself when the old lady came back and stood above the wreck -discharging lightnings of wrath from over her spectacles. He said to -himself, "Now it's coming!" And the next instant he was sprawling on -the floor! The potent palm was uplifted to strike again when Tom cried -out: - -"Hold on, now, what 'er you belting ME for?--Sid broke it!" - -Aunt Polly paused, perplexed, and Tom looked for healing pity. But -when she got her tongue again, she only said: - -"Umf! Well, you didn't get a lick amiss, I reckon. You been into some -other audacious mischief when I wasn't around, like enough." - -Then her conscience reproached her, and she yearned to say something -kind and loving; but she judged that this would be construed into a -confession that she had been in the wrong, and discipline forbade that. -So she kept silence, and went about her affairs with a troubled heart. -Tom sulked in a corner and exalted his woes. He knew that in her heart -his aunt was on her knees to him, and he was morosely gratified by the -consciousness of it. He would hang out no signals, he would take notice -of none. He knew that a yearning glance fell upon him, now and then, -through a film of tears, but he refused recognition of it. He pictured -himself lying sick unto death and his aunt bending over him beseeching -one little forgiving word, but he would turn his face to the wall, and -die with that word unsaid. Ah, how would she feel then? And he pictured -himself brought home from the river, dead, with his curls all wet, and -his sore heart at rest. How she would throw herself upon him, and how -her tears would fall like rain, and her lips pray God to give her back -her boy and she would never, never abuse him any more! But he would lie -there cold and white and make no sign--a poor little sufferer, whose -griefs were at an end. He so worked upon his feelings with the pathos -of these dreams, that he had to keep swallowing, he was so like to -choke; and his eyes swam in a blur of water, which overflowed when he -winked, and ran down and trickled from the end of his nose. And such a -luxury to him was this petting of his sorrows, that he could not bear -to have any worldly cheeriness or any grating delight intrude upon it; -it was too sacred for such contact; and so, presently, when his cousin -Mary danced in, all alive with the joy of seeing home again after an -age-long visit of one week to the country, he got up and moved in -clouds and darkness out at one door as she brought song and sunshine in -at the other. - -He wandered far from the accustomed haunts of boys, and sought -desolate places that were in harmony with his spirit. A log raft in the -river invited him, and he seated himself on its outer edge and -contemplated the dreary vastness of the stream, wishing, the while, -that he could only be drowned, all at once and unconsciously, without -undergoing the uncomfortable routine devised by nature. Then he thought -of his flower. He got it out, rumpled and wilted, and it mightily -increased his dismal felicity. He wondered if she would pity him if she -knew? Would she cry, and wish that she had a right to put her arms -around his neck and comfort him? Or would she turn coldly away like all -the hollow world? This picture brought such an agony of pleasurable -suffering that he worked it over and over again in his mind and set it -up in new and varied lights, till he wore it threadbare. At last he -rose up sighing and departed in the darkness. - -About half-past nine or ten o'clock he came along the deserted street -to where the Adored Unknown lived; he paused a moment; no sound fell -upon his listening ear; a candle was casting a dull glow upon the -curtain of a second-story window. Was the sacred presence there? He -climbed the fence, threaded his stealthy way through the plants, till -he stood under that window; he looked up at it long, and with emotion; -then he laid him down on the ground under it, disposing himself upon -his back, with his hands clasped upon his breast and holding his poor -wilted flower. And thus he would die--out in the cold world, with no -shelter over his homeless head, no friendly hand to wipe the -death-damps from his brow, no loving face to bend pityingly over him -when the great agony came. And thus SHE would see him when she looked -out upon the glad morning, and oh! would she drop one little tear upon -his poor, lifeless form, would she heave one little sigh to see a bright -young life so rudely blighted, so untimely cut down? - -The window went up, a maid-servant's discordant voice profaned the -holy calm, and a deluge of water drenched the prone martyr's remains! - -The strangling hero sprang up with a relieving snort. There was a whiz -as of a missile in the air, mingled with the murmur of a curse, a sound -as of shivering glass followed, and a small, vague form went over the -fence and shot away in the gloom. - -Not long after, as Tom, all undressed for bed, was surveying his -drenched garments by the light of a tallow dip, Sid woke up; but if he -had any dim idea of making any "references to allusions," he thought -better of it and held his peace, for there was danger in Tom's eye. - -Tom turned in without the added vexation of prayers, and Sid made -mental note of the omission. - - - -CHAPTER IV - -THE sun rose upon a tranquil world, and beamed down upon the peaceful -village like a benediction. Breakfast over, Aunt Polly had family -worship: it began with a prayer built from the ground up of solid -courses of Scriptural quotations, welded together with a thin mortar of -originality; and from the summit of this she delivered a grim chapter -of the Mosaic Law, as from Sinai. - -Then Tom girded up his loins, so to speak, and went to work to "get -his verses." Sid had learned his lesson days before. Tom bent all his -energies to the memorizing of five verses, and he chose part of the -Sermon on the Mount, because he could find no verses that were shorter. -At the end of half an hour Tom had a vague general idea of his lesson, -but no more, for his mind was traversing the whole field of human -thought, and his hands were busy with distracting recreations. Mary -took his book to hear him recite, and he tried to find his way through -the fog: - -"Blessed are the--a--a--" - -"Poor"-- - -"Yes--poor; blessed are the poor--a--a--" - -"In spirit--" - -"In spirit; blessed are the poor in spirit, for they--they--" - -"THEIRS--" - -"For THEIRS. Blessed are the poor in spirit, for theirs is the kingdom -of heaven. Blessed are they that mourn, for they--they--" - -"Sh--" - -"For they--a--" - -"S, H, A--" - -"For they S, H--Oh, I don't know what it is!" - -"SHALL!" - -"Oh, SHALL! for they shall--for they shall--a--a--shall mourn--a--a-- -blessed are they that shall--they that--a--they that shall mourn, for -they shall--a--shall WHAT? Why don't you tell me, Mary?--what do you -want to be so mean for?" - -"Oh, Tom, you poor thick-headed thing, I'm not teasing you. I wouldn't -do that. You must go and learn it again. Don't you be discouraged, Tom, -you'll manage it--and if you do, I'll give you something ever so nice. -There, now, that's a good boy." - -"All right! What is it, Mary, tell me what it is." - -"Never you mind, Tom. You know if I say it's nice, it is nice." - -"You bet you that's so, Mary. All right, I'll tackle it again." - -And he did "tackle it again"--and under the double pressure of -curiosity and prospective gain he did it with such spirit that he -accomplished a shining success. Mary gave him a brand-new "Barlow" -knife worth twelve and a half cents; and the convulsion of delight that -swept his system shook him to his foundations. True, the knife would -not cut anything, but it was a "sure-enough" Barlow, and there was -inconceivable grandeur in that--though where the Western boys ever got -the idea that such a weapon could possibly be counterfeited to its -injury is an imposing mystery and will always remain so, perhaps. Tom -contrived to scarify the cupboard with it, and was arranging to begin -on the bureau, when he was called off to dress for Sunday-school. - -Mary gave him a tin basin of water and a piece of soap, and he went -outside the door and set the basin on a little bench there; then he -dipped the soap in the water and laid it down; turned up his sleeves; -poured out the water on the ground, gently, and then entered the -kitchen and began to wipe his face diligently on the towel behind the -door. But Mary removed the towel and said: - -"Now ain't you ashamed, Tom. You mustn't be so bad. Water won't hurt -you." - -Tom was a trifle disconcerted. The basin was refilled, and this time -he stood over it a little while, gathering resolution; took in a big -breath and began. When he entered the kitchen presently, with both eyes -shut and groping for the towel with his hands, an honorable testimony -of suds and water was dripping from his face. But when he emerged from -the towel, he was not yet satisfactory, for the clean territory stopped -short at his chin and his jaws, like a mask; below and beyond this line -there was a dark expanse of unirrigated soil that spread downward in -front and backward around his neck. Mary took him in hand, and when she -was done with him he was a man and a brother, without distinction of -color, and his saturated hair was neatly brushed, and its short curls -wrought into a dainty and symmetrical general effect. [He privately -smoothed out the curls, with labor and difficulty, and plastered his -hair close down to his head; for he held curls to be effeminate, and -his own filled his life with bitterness.] Then Mary got out a suit of -his clothing that had been used only on Sundays during two years--they -were simply called his "other clothes"--and so by that we know the -size of his wardrobe. The girl "put him to rights" after he had dressed -himself; she buttoned his neat roundabout up to his chin, turned his -vast shirt collar down over his shoulders, brushed him off and crowned -him with his speckled straw hat. He now looked exceedingly improved and -uncomfortable. He was fully as uncomfortable as he looked; for there -was a restraint about whole clothes and cleanliness that galled him. He -hoped that Mary would forget his shoes, but the hope was blighted; she -coated them thoroughly with tallow, as was the custom, and brought them -out. He lost his temper and said he was always being made to do -everything he didn't want to do. But Mary said, persuasively: - -"Please, Tom--that's a good boy." - -So he got into the shoes snarling. Mary was soon ready, and the three -children set out for Sunday-school--a place that Tom hated with his -whole heart; but Sid and Mary were fond of it. - -Sabbath-school hours were from nine to half-past ten; and then church -service. Two of the children always remained for the sermon -voluntarily, and the other always remained too--for stronger reasons. -The church's high-backed, uncushioned pews would seat about three -hundred persons; the edifice was but a small, plain affair, with a sort -of pine board tree-box on top of it for a steeple. At the door Tom -dropped back a step and accosted a Sunday-dressed comrade: - -"Say, Billy, got a yaller ticket?" - -"Yes." - -"What'll you take for her?" - -"What'll you give?" - -"Piece of lickrish and a fish-hook." - -"Less see 'em." - -Tom exhibited. They were satisfactory, and the property changed hands. -Then Tom traded a couple of white alleys for three red tickets, and -some small trifle or other for a couple of blue ones. He waylaid other -boys as they came, and went on buying tickets of various colors ten or -fifteen minutes longer. He entered the church, now, with a swarm of -clean and noisy boys and girls, proceeded to his seat and started a -quarrel with the first boy that came handy. The teacher, a grave, -elderly man, interfered; then turned his back a moment and Tom pulled a -boy's hair in the next bench, and was absorbed in his book when the boy -turned around; stuck a pin in another boy, presently, in order to hear -him say "Ouch!" and got a new reprimand from his teacher. Tom's whole -class were of a pattern--restless, noisy, and troublesome. When they -came to recite their lessons, not one of them knew his verses -perfectly, but had to be prompted all along. However, they worried -through, and each got his reward--in small blue tickets, each with a -passage of Scripture on it; each blue ticket was pay for two verses of -the recitation. Ten blue tickets equalled a red one, and could be -exchanged for it; ten red tickets equalled a yellow one; for ten yellow -tickets the superintendent gave a very plainly bound Bible (worth forty -cents in those easy times) to the pupil. How many of my readers would -have the industry and application to memorize two thousand verses, even -for a Dore Bible? And yet Mary had acquired two Bibles in this way--it -was the patient work of two years--and a boy of German parentage had -won four or five. He once recited three thousand verses without -stopping; but the strain upon his mental faculties was too great, and -he was little better than an idiot from that day forth--a grievous -misfortune for the school, for on great occasions, before company, the -superintendent (as Tom expressed it) had always made this boy come out -and "spread himself." Only the older pupils managed to keep their -tickets and stick to their tedious work long enough to get a Bible, and -so the delivery of one of these prizes was a rare and noteworthy -circumstance; the successful pupil was so great and conspicuous for -that day that on the spot every scholar's heart was fired with a fresh -ambition that often lasted a couple of weeks. It is possible that Tom's -mental stomach had never really hungered for one of those prizes, but -unquestionably his entire being had for many a day longed for the glory -and the eclat that came with it. - -In due course the superintendent stood up in front of the pulpit, with -a closed hymn-book in his hand and his forefinger inserted between its -leaves, and commanded attention. When a Sunday-school superintendent -makes his customary little speech, a hymn-book in the hand is as -necessary as is the inevitable sheet of music in the hand of a singer -who stands forward on the platform and sings a solo at a concert ---though why, is a mystery: for neither the hymn-book nor the sheet of -music is ever referred to by the sufferer. This superintendent was a -slim creature of thirty-five, with a sandy goatee and short sandy hair; -he wore a stiff standing-collar whose upper edge almost reached his -ears and whose sharp points curved forward abreast the corners of his -mouth--a fence that compelled a straight lookout ahead, and a turning -of the whole body when a side view was required; his chin was propped -on a spreading cravat which was as broad and as long as a bank-note, -and had fringed ends; his boot toes were turned sharply up, in the -fashion of the day, like sleigh-runners--an effect patiently and -laboriously produced by the young men by sitting with their toes -pressed against a wall for hours together. Mr. Walters was very earnest -of mien, and very sincere and honest at heart; and he held sacred -things and places in such reverence, and so separated them from worldly -matters, that unconsciously to himself his Sunday-school voice had -acquired a peculiar intonation which was wholly absent on week-days. He -began after this fashion: - -"Now, children, I want you all to sit up just as straight and pretty -as you can and give me all your attention for a minute or two. There ---that is it. That is the way good little boys and girls should do. I see -one little girl who is looking out of the window--I am afraid she -thinks I am out there somewhere--perhaps up in one of the trees making -a speech to the little birds. [Applausive titter.] I want to tell you -how good it makes me feel to see so many bright, clean little faces -assembled in a place like this, learning to do right and be good." And -so forth and so on. It is not necessary to set down the rest of the -oration. It was of a pattern which does not vary, and so it is familiar -to us all. - -The latter third of the speech was marred by the resumption of fights -and other recreations among certain of the bad boys, and by fidgetings -and whisperings that extended far and wide, washing even to the bases -of isolated and incorruptible rocks like Sid and Mary. But now every -sound ceased suddenly, with the subsidence of Mr. Walters' voice, and -the conclusion of the speech was received with a burst of silent -gratitude. - -A good part of the whispering had been occasioned by an event which -was more or less rare--the entrance of visitors: lawyer Thatcher, -accompanied by a very feeble and aged man; a fine, portly, middle-aged -gentleman with iron-gray hair; and a dignified lady who was doubtless -the latter's wife. The lady was leading a child. Tom had been restless -and full of chafings and repinings; conscience-smitten, too--he could -not meet Amy Lawrence's eye, he could not brook her loving gaze. But -when he saw this small new-comer his soul was all ablaze with bliss in -a moment. The next moment he was "showing off" with all his might ---cuffing boys, pulling hair, making faces--in a word, using every art -that seemed likely to fascinate a girl and win her applause. His -exaltation had but one alloy--the memory of his humiliation in this -angel's garden--and that record in sand was fast washing out, under -the waves of happiness that were sweeping over it now. - -The visitors were given the highest seat of honor, and as soon as Mr. -Walters' speech was finished, he introduced them to the school. The -middle-aged man turned out to be a prodigious personage--no less a one -than the county judge--altogether the most august creation these -children had ever looked upon--and they wondered what kind of material -he was made of--and they half wanted to hear him roar, and were half -afraid he might, too. He was from Constantinople, twelve miles away--so -he had travelled, and seen the world--these very eyes had looked upon -the county court-house--which was said to have a tin roof. The awe -which these reflections inspired was attested by the impressive silence -and the ranks of staring eyes. This was the great Judge Thatcher, -brother of their own lawyer. Jeff Thatcher immediately went forward, to -be familiar with the great man and be envied by the school. It would -have been music to his soul to hear the whisperings: - -"Look at him, Jim! He's a going up there. Say--look! he's a going to -shake hands with him--he IS shaking hands with him! By jings, don't you -wish you was Jeff?" - -Mr. Walters fell to "showing off," with all sorts of official -bustlings and activities, giving orders, delivering judgments, -discharging directions here, there, everywhere that he could find a -target. The librarian "showed off"--running hither and thither with his -arms full of books and making a deal of the splutter and fuss that -insect authority delights in. The young lady teachers "showed off" ---bending sweetly over pupils that were lately being boxed, lifting -pretty warning fingers at bad little boys and patting good ones -lovingly. The young gentlemen teachers "showed off" with small -scoldings and other little displays of authority and fine attention to -discipline--and most of the teachers, of both sexes, found business up -at the library, by the pulpit; and it was business that frequently had -to be done over again two or three times (with much seeming vexation). -The little girls "showed off" in various ways, and the little boys -"showed off" with such diligence that the air was thick with paper wads -and the murmur of scufflings. And above it all the great man sat and -beamed a majestic judicial smile upon all the house, and warmed himself -in the sun of his own grandeur--for he was "showing off," too. - -There was only one thing wanting to make Mr. Walters' ecstasy -complete, and that was a chance to deliver a Bible-prize and exhibit a -prodigy. Several pupils had a few yellow tickets, but none had enough ---he had been around among the star pupils inquiring. He would have given -worlds, now, to have that German lad back again with a sound mind. - -And now at this moment, when hope was dead, Tom Sawyer came forward -with nine yellow tickets, nine red tickets, and ten blue ones, and -demanded a Bible. This was a thunderbolt out of a clear sky. Walters -was not expecting an application from this source for the next ten -years. But there was no getting around it--here were the certified -checks, and they were good for their face. Tom was therefore elevated -to a place with the Judge and the other elect, and the great news was -announced from headquarters. It was the most stunning surprise of the -decade, and so profound was the sensation that it lifted the new hero -up to the judicial one's altitude, and the school had two marvels to -gaze upon in place of one. The boys were all eaten up with envy--but -those that suffered the bitterest pangs were those who perceived too -late that they themselves had contributed to this hated splendor by -trading tickets to Tom for the wealth he had amassed in selling -whitewashing privileges. These despised themselves, as being the dupes -of a wily fraud, a guileful snake in the grass. - -The prize was delivered to Tom with as much effusion as the -superintendent could pump up under the circumstances; but it lacked -somewhat of the true gush, for the poor fellow's instinct taught him -that there was a mystery here that could not well bear the light, -perhaps; it was simply preposterous that this boy had warehoused two -thousand sheaves of Scriptural wisdom on his premises--a dozen would -strain his capacity, without a doubt. - -Amy Lawrence was proud and glad, and she tried to make Tom see it in -her face--but he wouldn't look. She wondered; then she was just a grain -troubled; next a dim suspicion came and went--came again; she watched; -a furtive glance told her worlds--and then her heart broke, and she was -jealous, and angry, and the tears came and she hated everybody. Tom -most of all (she thought). - -Tom was introduced to the Judge; but his tongue was tied, his breath -would hardly come, his heart quaked--partly because of the awful -greatness of the man, but mainly because he was her parent. He would -have liked to fall down and worship him, if it were in the dark. The -Judge put his hand on Tom's head and called him a fine little man, and -asked him what his name was. The boy stammered, gasped, and got it out: - -"Tom." - -"Oh, no, not Tom--it is--" - -"Thomas." - -"Ah, that's it. I thought there was more to it, maybe. That's very -well. But you've another one I daresay, and you'll tell it to me, won't -you?" - -"Tell the gentleman your other name, Thomas," said Walters, "and say -sir. You mustn't forget your manners." - -"Thomas Sawyer--sir." - -"That's it! That's a good boy. Fine boy. Fine, manly little fellow. -Two thousand verses is a great many--very, very great many. And you -never can be sorry for the trouble you took to learn them; for -knowledge is worth more than anything there is in the world; it's what -makes great men and good men; you'll be a great man and a good man -yourself, some day, Thomas, and then you'll look back and say, It's all -owing to the precious Sunday-school privileges of my boyhood--it's all -owing to my dear teachers that taught me to learn--it's all owing to -the good superintendent, who encouraged me, and watched over me, and -gave me a beautiful Bible--a splendid elegant Bible--to keep and have -it all for my own, always--it's all owing to right bringing up! That is -what you will say, Thomas--and you wouldn't take any money for those -two thousand verses--no indeed you wouldn't. And now you wouldn't mind -telling me and this lady some of the things you've learned--no, I know -you wouldn't--for we are proud of little boys that learn. Now, no -doubt you know the names of all the twelve disciples. Won't you tell us -the names of the first two that were appointed?" - -Tom was tugging at a button-hole and looking sheepish. He blushed, -now, and his eyes fell. Mr. Walters' heart sank within him. He said to -himself, it is not possible that the boy can answer the simplest -question--why DID the Judge ask him? Yet he felt obliged to speak up -and say: - -"Answer the gentleman, Thomas--don't be afraid." - -Tom still hung fire. - -"Now I know you'll tell me," said the lady. "The names of the first -two disciples were--" - -"DAVID AND GOLIAH!" - -Let us draw the curtain of charity over the rest of the scene. - - - -CHAPTER V - -ABOUT half-past ten the cracked bell of the small church began to -ring, and presently the people began to gather for the morning sermon. -The Sunday-school children distributed themselves about the house and -occupied pews with their parents, so as to be under supervision. Aunt -Polly came, and Tom and Sid and Mary sat with her--Tom being placed -next the aisle, in order that he might be as far away from the open -window and the seductive outside summer scenes as possible. The crowd -filed up the aisles: the aged and needy postmaster, who had seen better -days; the mayor and his wife--for they had a mayor there, among other -unnecessaries; the justice of the peace; the widow Douglass, fair, -smart, and forty, a generous, good-hearted soul and well-to-do, her -hill mansion the only palace in the town, and the most hospitable and -much the most lavish in the matter of festivities that St. Petersburg -could boast; the bent and venerable Major and Mrs. Ward; lawyer -Riverson, the new notable from a distance; next the belle of the -village, followed by a troop of lawn-clad and ribbon-decked young -heart-breakers; then all the young clerks in town in a body--for they -had stood in the vestibule sucking their cane-heads, a circling wall of -oiled and simpering admirers, till the last girl had run their gantlet; -and last of all came the Model Boy, Willie Mufferson, taking as heedful -care of his mother as if she were cut glass. He always brought his -mother to church, and was the pride of all the matrons. The boys all -hated him, he was so good. And besides, he had been "thrown up to them" -so much. His white handkerchief was hanging out of his pocket behind, as -usual on Sundays--accidentally. Tom had no handkerchief, and he looked -upon boys who had as snobs. - -The congregation being fully assembled, now, the bell rang once more, -to warn laggards and stragglers, and then a solemn hush fell upon the -church which was only broken by the tittering and whispering of the -choir in the gallery. The choir always tittered and whispered all -through service. There was once a church choir that was not ill-bred, -but I have forgotten where it was, now. It was a great many years ago, -and I can scarcely remember anything about it, but I think it was in -some foreign country. - -The minister gave out the hymn, and read it through with a relish, in -a peculiar style which was much admired in that part of the country. -His voice began on a medium key and climbed steadily up till it reached -a certain point, where it bore with strong emphasis upon the topmost -word and then plunged down as if from a spring-board: - - Shall I be car-ri-ed toe the skies, on flow'ry BEDS of ease, - - Whilst others fight to win the prize, and sail thro' BLOODY seas? - -He was regarded as a wonderful reader. At church "sociables" he was -always called upon to read poetry; and when he was through, the ladies -would lift up their hands and let them fall helplessly in their laps, -and "wall" their eyes, and shake their heads, as much as to say, "Words -cannot express it; it is too beautiful, TOO beautiful for this mortal -earth." - -After the hymn had been sung, the Rev. Mr. Sprague turned himself into -a bulletin-board, and read off "notices" of meetings and societies and -things till it seemed that the list would stretch out to the crack of -doom--a queer custom which is still kept up in America, even in cities, -away here in this age of abundant newspapers. Often, the less there is -to justify a traditional custom, the harder it is to get rid of it. - -And now the minister prayed. A good, generous prayer it was, and went -into details: it pleaded for the church, and the little children of the -church; for the other churches of the village; for the village itself; -for the county; for the State; for the State officers; for the United -States; for the churches of the United States; for Congress; for the -President; for the officers of the Government; for poor sailors, tossed -by stormy seas; for the oppressed millions groaning under the heel of -European monarchies and Oriental despotisms; for such as have the light -and the good tidings, and yet have not eyes to see nor ears to hear -withal; for the heathen in the far islands of the sea; and closed with -a supplication that the words he was about to speak might find grace -and favor, and be as seed sown in fertile ground, yielding in time a -grateful harvest of good. Amen. - -There was a rustling of dresses, and the standing congregation sat -down. The boy whose history this book relates did not enjoy the prayer, -he only endured it--if he even did that much. He was restive all -through it; he kept tally of the details of the prayer, unconsciously ---for he was not listening, but he knew the ground of old, and the -clergyman's regular route over it--and when a little trifle of new -matter was interlarded, his ear detected it and his whole nature -resented it; he considered additions unfair, and scoundrelly. In the -midst of the prayer a fly had lit on the back of the pew in front of -him and tortured his spirit by calmly rubbing its hands together, -embracing its head with its arms, and polishing it so vigorously that -it seemed to almost part company with the body, and the slender thread -of a neck was exposed to view; scraping its wings with its hind legs -and smoothing them to its body as if they had been coat-tails; going -through its whole toilet as tranquilly as if it knew it was perfectly -safe. As indeed it was; for as sorely as Tom's hands itched to grab for -it they did not dare--he believed his soul would be instantly destroyed -if he did such a thing while the prayer was going on. But with the -closing sentence his hand began to curve and steal forward; and the -instant the "Amen" was out the fly was a prisoner of war. His aunt -detected the act and made him let it go. - -The minister gave out his text and droned along monotonously through -an argument that was so prosy that many a head by and by began to nod ---and yet it was an argument that dealt in limitless fire and brimstone -and thinned the predestined elect down to a company so small as to be -hardly worth the saving. Tom counted the pages of the sermon; after -church he always knew how many pages there had been, but he seldom knew -anything else about the discourse. However, this time he was really -interested for a little while. The minister made a grand and moving -picture of the assembling together of the world's hosts at the -millennium when the lion and the lamb should lie down together and a -little child should lead them. But the pathos, the lesson, the moral of -the great spectacle were lost upon the boy; he only thought of the -conspicuousness of the principal character before the on-looking -nations; his face lit with the thought, and he said to himself that he -wished he could be that child, if it was a tame lion. - -Now he lapsed into suffering again, as the dry argument was resumed. -Presently he bethought him of a treasure he had and got it out. It was -a large black beetle with formidable jaws--a "pinchbug," he called it. -It was in a percussion-cap box. The first thing the beetle did was to -take him by the finger. A natural fillip followed, the beetle went -floundering into the aisle and lit on its back, and the hurt finger -went into the boy's mouth. The beetle lay there working its helpless -legs, unable to turn over. Tom eyed it, and longed for it; but it was -safe out of his reach. Other people uninterested in the sermon found -relief in the beetle, and they eyed it too. Presently a vagrant poodle -dog came idling along, sad at heart, lazy with the summer softness and -the quiet, weary of captivity, sighing for change. He spied the beetle; -the drooping tail lifted and wagged. He surveyed the prize; walked -around it; smelt at it from a safe distance; walked around it again; -grew bolder, and took a closer smell; then lifted his lip and made a -gingerly snatch at it, just missing it; made another, and another; -began to enjoy the diversion; subsided to his stomach with the beetle -between his paws, and continued his experiments; grew weary at last, -and then indifferent and absent-minded. His head nodded, and little by -little his chin descended and touched the enemy, who seized it. There -was a sharp yelp, a flirt of the poodle's head, and the beetle fell a -couple of yards away, and lit on its back once more. The neighboring -spectators shook with a gentle inward joy, several faces went behind -fans and handkerchiefs, and Tom was entirely happy. The dog looked -foolish, and probably felt so; but there was resentment in his heart, -too, and a craving for revenge. So he went to the beetle and began a -wary attack on it again; jumping at it from every point of a circle, -lighting with his fore-paws within an inch of the creature, making even -closer snatches at it with his teeth, and jerking his head till his -ears flapped again. But he grew tired once more, after a while; tried -to amuse himself with a fly but found no relief; followed an ant -around, with his nose close to the floor, and quickly wearied of that; -yawned, sighed, forgot the beetle entirely, and sat down on it. Then -there was a wild yelp of agony and the poodle went sailing up the -aisle; the yelps continued, and so did the dog; he crossed the house in -front of the altar; he flew down the other aisle; he crossed before the -doors; he clamored up the home-stretch; his anguish grew with his -progress, till presently he was but a woolly comet moving in its orbit -with the gleam and the speed of light. At last the frantic sufferer -sheered from its course, and sprang into its master's lap; he flung it -out of the window, and the voice of distress quickly thinned away and -died in the distance. - -By this time the whole church was red-faced and suffocating with -suppressed laughter, and the sermon had come to a dead standstill. The -discourse was resumed presently, but it went lame and halting, all -possibility of impressiveness being at an end; for even the gravest -sentiments were constantly being received with a smothered burst of -unholy mirth, under cover of some remote pew-back, as if the poor -parson had said a rarely facetious thing. It was a genuine relief to -the whole congregation when the ordeal was over and the benediction -pronounced. - -Tom Sawyer went home quite cheerful, thinking to himself that there -was some satisfaction about divine service when there was a bit of -variety in it. He had but one marring thought; he was willing that the -dog should play with his pinchbug, but he did not think it was upright -in him to carry it off. - - - -CHAPTER VI - -MONDAY morning found Tom Sawyer miserable. Monday morning always found -him so--because it began another week's slow suffering in school. He -generally began that day with wishing he had had no intervening -holiday, it made the going into captivity and fetters again so much -more odious. - -Tom lay thinking. Presently it occurred to him that he wished he was -sick; then he could stay home from school. Here was a vague -possibility. He canvassed his system. No ailment was found, and he -investigated again. This time he thought he could detect colicky -symptoms, and he began to encourage them with considerable hope. But -they soon grew feeble, and presently died wholly away. He reflected -further. Suddenly he discovered something. One of his upper front teeth -was loose. This was lucky; he was about to begin to groan, as a -"starter," as he called it, when it occurred to him that if he came -into court with that argument, his aunt would pull it out, and that -would hurt. So he thought he would hold the tooth in reserve for the -present, and seek further. Nothing offered for some little time, and -then he remembered hearing the doctor tell about a certain thing that -laid up a patient for two or three weeks and threatened to make him -lose a finger. So the boy eagerly drew his sore toe from under the -sheet and held it up for inspection. But now he did not know the -necessary symptoms. However, it seemed well worth while to chance it, -so he fell to groaning with considerable spirit. - -But Sid slept on unconscious. - -Tom groaned louder, and fancied that he began to feel pain in the toe. - -No result from Sid. - -Tom was panting with his exertions by this time. He took a rest and -then swelled himself up and fetched a succession of admirable groans. - -Sid snored on. - -Tom was aggravated. He said, "Sid, Sid!" and shook him. This course -worked well, and Tom began to groan again. Sid yawned, stretched, then -brought himself up on his elbow with a snort, and began to stare at -Tom. Tom went on groaning. Sid said: - -"Tom! Say, Tom!" [No response.] "Here, Tom! TOM! What is the matter, -Tom?" And he shook him and looked in his face anxiously. - -Tom moaned out: - -"Oh, don't, Sid. Don't joggle me." - -"Why, what's the matter, Tom? I must call auntie." - -"No--never mind. It'll be over by and by, maybe. Don't call anybody." - -"But I must! DON'T groan so, Tom, it's awful. How long you been this -way?" - -"Hours. Ouch! Oh, don't stir so, Sid, you'll kill me." - -"Tom, why didn't you wake me sooner? Oh, Tom, DON'T! It makes my -flesh crawl to hear you. Tom, what is the matter?" - -"I forgive you everything, Sid. [Groan.] Everything you've ever done -to me. When I'm gone--" - -"Oh, Tom, you ain't dying, are you? Don't, Tom--oh, don't. Maybe--" - -"I forgive everybody, Sid. [Groan.] Tell 'em so, Sid. And Sid, you -give my window-sash and my cat with one eye to that new girl that's -come to town, and tell her--" - -But Sid had snatched his clothes and gone. Tom was suffering in -reality, now, so handsomely was his imagination working, and so his -groans had gathered quite a genuine tone. - -Sid flew down-stairs and said: - -"Oh, Aunt Polly, come! Tom's dying!" - -"Dying!" - -"Yes'm. Don't wait--come quick!" - -"Rubbage! I don't believe it!" - -But she fled up-stairs, nevertheless, with Sid and Mary at her heels. -And her face grew white, too, and her lip trembled. When she reached -the bedside she gasped out: - -"You, Tom! Tom, what's the matter with you?" - -"Oh, auntie, I'm--" - -"What's the matter with you--what is the matter with you, child?" - -"Oh, auntie, my sore toe's mortified!" - -The old lady sank down into a chair and laughed a little, then cried a -little, then did both together. This restored her and she said: - -"Tom, what a turn you did give me. Now you shut up that nonsense and -climb out of this." - -The groans ceased and the pain vanished from the toe. The boy felt a -little foolish, and he said: - -"Aunt Polly, it SEEMED mortified, and it hurt so I never minded my -tooth at all." - -"Your tooth, indeed! What's the matter with your tooth?" - -"One of them's loose, and it aches perfectly awful." - -"There, there, now, don't begin that groaning again. Open your mouth. -Well--your tooth IS loose, but you're not going to die about that. -Mary, get me a silk thread, and a chunk of fire out of the kitchen." - -Tom said: - -"Oh, please, auntie, don't pull it out. It don't hurt any more. I wish -I may never stir if it does. Please don't, auntie. I don't want to stay -home from school." - -"Oh, you don't, don't you? So all this row was because you thought -you'd get to stay home from school and go a-fishing? Tom, Tom, I love -you so, and you seem to try every way you can to break my old heart -with your outrageousness." By this time the dental instruments were -ready. The old lady made one end of the silk thread fast to Tom's tooth -with a loop and tied the other to the bedpost. Then she seized the -chunk of fire and suddenly thrust it almost into the boy's face. The -tooth hung dangling by the bedpost, now. - -But all trials bring their compensations. As Tom wended to school -after breakfast, he was the envy of every boy he met because the gap in -his upper row of teeth enabled him to expectorate in a new and -admirable way. He gathered quite a following of lads interested in the -exhibition; and one that had cut his finger and had been a centre of -fascination and homage up to this time, now found himself suddenly -without an adherent, and shorn of his glory. His heart was heavy, and -he said with a disdain which he did not feel that it wasn't anything to -spit like Tom Sawyer; but another boy said, "Sour grapes!" and he -wandered away a dismantled hero. - -Shortly Tom came upon the juvenile pariah of the village, Huckleberry -Finn, son of the town drunkard. Huckleberry was cordially hated and -dreaded by all the mothers of the town, because he was idle and lawless -and vulgar and bad--and because all their children admired him so, and -delighted in his forbidden society, and wished they dared to be like -him. Tom was like the rest of the respectable boys, in that he envied -Huckleberry his gaudy outcast condition, and was under strict orders -not to play with him. So he played with him every time he got a chance. -Huckleberry was always dressed in the cast-off clothes of full-grown -men, and they were in perennial bloom and fluttering with rags. His hat -was a vast ruin with a wide crescent lopped out of its brim; his coat, -when he wore one, hung nearly to his heels and had the rearward buttons -far down the back; but one suspender supported his trousers; the seat -of the trousers bagged low and contained nothing, the fringed legs -dragged in the dirt when not rolled up. - -Huckleberry came and went, at his own free will. He slept on doorsteps -in fine weather and in empty hogsheads in wet; he did not have to go to -school or to church, or call any being master or obey anybody; he could -go fishing or swimming when and where he chose, and stay as long as it -suited him; nobody forbade him to fight; he could sit up as late as he -pleased; he was always the first boy that went barefoot in the spring -and the last to resume leather in the fall; he never had to wash, nor -put on clean clothes; he could swear wonderfully. In a word, everything -that goes to make life precious that boy had. So thought every -harassed, hampered, respectable boy in St. Petersburg. - -Tom hailed the romantic outcast: - -"Hello, Huckleberry!" - -"Hello yourself, and see how you like it." - -"What's that you got?" - -"Dead cat." - -"Lemme see him, Huck. My, he's pretty stiff. Where'd you get him?" - -"Bought him off'n a boy." - -"What did you give?" - -"I give a blue ticket and a bladder that I got at the slaughter-house." - -"Where'd you get the blue ticket?" - -"Bought it off'n Ben Rogers two weeks ago for a hoop-stick." - -"Say--what is dead cats good for, Huck?" - -"Good for? Cure warts with." - -"No! Is that so? I know something that's better." - -"I bet you don't. What is it?" - -"Why, spunk-water." - -"Spunk-water! I wouldn't give a dern for spunk-water." - -"You wouldn't, wouldn't you? D'you ever try it?" - -"No, I hain't. But Bob Tanner did." - -"Who told you so!" - -"Why, he told Jeff Thatcher, and Jeff told Johnny Baker, and Johnny -told Jim Hollis, and Jim told Ben Rogers, and Ben told a nigger, and -the nigger told me. There now!" - -"Well, what of it? They'll all lie. Leastways all but the nigger. I -don't know HIM. But I never see a nigger that WOULDN'T lie. Shucks! Now -you tell me how Bob Tanner done it, Huck." - -"Why, he took and dipped his hand in a rotten stump where the -rain-water was." - -"In the daytime?" - -"Certainly." - -"With his face to the stump?" - -"Yes. Least I reckon so." - -"Did he say anything?" - -"I don't reckon he did. I don't know." - -"Aha! Talk about trying to cure warts with spunk-water such a blame -fool way as that! Why, that ain't a-going to do any good. You got to go -all by yourself, to the middle of the woods, where you know there's a -spunk-water stump, and just as it's midnight you back up against the -stump and jam your hand in and say: - - 'Barley-corn, barley-corn, injun-meal shorts, - Spunk-water, spunk-water, swaller these warts,' - -and then walk away quick, eleven steps, with your eyes shut, and then -turn around three times and walk home without speaking to anybody. -Because if you speak the charm's busted." - -"Well, that sounds like a good way; but that ain't the way Bob Tanner -done." - -"No, sir, you can bet he didn't, becuz he's the wartiest boy in this -town; and he wouldn't have a wart on him if he'd knowed how to work -spunk-water. I've took off thousands of warts off of my hands that way, -Huck. I play with frogs so much that I've always got considerable many -warts. Sometimes I take 'em off with a bean." - -"Yes, bean's good. I've done that." - -"Have you? What's your way?" - -"You take and split the bean, and cut the wart so as to get some -blood, and then you put the blood on one piece of the bean and take and -dig a hole and bury it 'bout midnight at the crossroads in the dark of -the moon, and then you burn up the rest of the bean. You see that piece -that's got the blood on it will keep drawing and drawing, trying to -fetch the other piece to it, and so that helps the blood to draw the -wart, and pretty soon off she comes." - -"Yes, that's it, Huck--that's it; though when you're burying it if you -say 'Down bean; off wart; come no more to bother me!' it's better. -That's the way Joe Harper does, and he's been nearly to Coonville and -most everywheres. But say--how do you cure 'em with dead cats?" - -"Why, you take your cat and go and get in the graveyard 'long about -midnight when somebody that was wicked has been buried; and when it's -midnight a devil will come, or maybe two or three, but you can't see -'em, you can only hear something like the wind, or maybe hear 'em talk; -and when they're taking that feller away, you heave your cat after 'em -and say, 'Devil follow corpse, cat follow devil, warts follow cat, I'm -done with ye!' That'll fetch ANY wart." - -"Sounds right. D'you ever try it, Huck?" - -"No, but old Mother Hopkins told me." - -"Well, I reckon it's so, then. Becuz they say she's a witch." - -"Say! Why, Tom, I KNOW she is. She witched pap. Pap says so his own -self. He come along one day, and he see she was a-witching him, so he -took up a rock, and if she hadn't dodged, he'd a got her. Well, that -very night he rolled off'n a shed wher' he was a layin drunk, and broke -his arm." - -"Why, that's awful. How did he know she was a-witching him?" - -"Lord, pap can tell, easy. Pap says when they keep looking at you -right stiddy, they're a-witching you. Specially if they mumble. Becuz -when they mumble they're saying the Lord's Prayer backards." - -"Say, Hucky, when you going to try the cat?" - -"To-night. I reckon they'll come after old Hoss Williams to-night." - -"But they buried him Saturday. Didn't they get him Saturday night?" - -"Why, how you talk! How could their charms work till midnight?--and -THEN it's Sunday. Devils don't slosh around much of a Sunday, I don't -reckon." - -"I never thought of that. That's so. Lemme go with you?" - -"Of course--if you ain't afeard." - -"Afeard! 'Tain't likely. Will you meow?" - -"Yes--and you meow back, if you get a chance. Last time, you kep' me -a-meowing around till old Hays went to throwing rocks at me and says -'Dern that cat!' and so I hove a brick through his window--but don't -you tell." - -"I won't. I couldn't meow that night, becuz auntie was watching me, -but I'll meow this time. Say--what's that?" - -"Nothing but a tick." - -"Where'd you get him?" - -"Out in the woods." - -"What'll you take for him?" - -"I don't know. I don't want to sell him." - -"All right. It's a mighty small tick, anyway." - -"Oh, anybody can run a tick down that don't belong to them. I'm -satisfied with it. It's a good enough tick for me." - -"Sho, there's ticks a plenty. I could have a thousand of 'em if I -wanted to." - -"Well, why don't you? Becuz you know mighty well you can't. This is a -pretty early tick, I reckon. It's the first one I've seen this year." - -"Say, Huck--I'll give you my tooth for him." - -"Less see it." - -Tom got out a bit of paper and carefully unrolled it. Huckleberry -viewed it wistfully. The temptation was very strong. At last he said: - -"Is it genuwyne?" - -Tom lifted his lip and showed the vacancy. - -"Well, all right," said Huckleberry, "it's a trade." - -Tom enclosed the tick in the percussion-cap box that had lately been -the pinchbug's prison, and the boys separated, each feeling wealthier -than before. - -When Tom reached the little isolated frame schoolhouse, he strode in -briskly, with the manner of one who had come with all honest speed. -He hung his hat on a peg and flung himself into his seat with -business-like alacrity. The master, throned on high in his great -splint-bottom arm-chair, was dozing, lulled by the drowsy hum of study. -The interruption roused him. - -"Thomas Sawyer!" - -Tom knew that when his name was pronounced in full, it meant trouble. - -"Sir!" - -"Come up here. Now, sir, why are you late again, as usual?" - -Tom was about to take refuge in a lie, when he saw two long tails of -yellow hair hanging down a back that he recognized by the electric -sympathy of love; and by that form was THE ONLY VACANT PLACE on the -girls' side of the schoolhouse. He instantly said: - -"I STOPPED TO TALK WITH HUCKLEBERRY FINN!" - -The master's pulse stood still, and he stared helplessly. The buzz of -study ceased. The pupils wondered if this foolhardy boy had lost his -mind. The master said: - -"You--you did what?" - -"Stopped to talk with Huckleberry Finn." - -There was no mistaking the words. - -"Thomas Sawyer, this is the most astounding confession I have ever -listened to. No mere ferule will answer for this offence. Take off your -jacket." - -The master's arm performed until it was tired and the stock of -switches notably diminished. Then the order followed: - -"Now, sir, go and sit with the girls! And let this be a warning to you." - -The titter that rippled around the room appeared to abash the boy, but -in reality that result was caused rather more by his worshipful awe of -his unknown idol and the dread pleasure that lay in his high good -fortune. He sat down upon the end of the pine bench and the girl -hitched herself away from him with a toss of her head. Nudges and winks -and whispers traversed the room, but Tom sat still, with his arms upon -the long, low desk before him, and seemed to study his book. - -By and by attention ceased from him, and the accustomed school murmur -rose upon the dull air once more. Presently the boy began to steal -furtive glances at the girl. She observed it, "made a mouth" at him and -gave him the back of her head for the space of a minute. When she -cautiously faced around again, a peach lay before her. She thrust it -away. Tom gently put it back. She thrust it away again, but with less -animosity. Tom patiently returned it to its place. Then she let it -remain. Tom scrawled on his slate, "Please take it--I got more." The -girl glanced at the words, but made no sign. Now the boy began to draw -something on the slate, hiding his work with his left hand. For a time -the girl refused to notice; but her human curiosity presently began to -manifest itself by hardly perceptible signs. The boy worked on, -apparently unconscious. The girl made a sort of noncommittal attempt to -see, but the boy did not betray that he was aware of it. At last she -gave in and hesitatingly whispered: - -"Let me see it." - -Tom partly uncovered a dismal caricature of a house with two gable -ends to it and a corkscrew of smoke issuing from the chimney. Then the -girl's interest began to fasten itself upon the work and she forgot -everything else. When it was finished, she gazed a moment, then -whispered: - -"It's nice--make a man." - -The artist erected a man in the front yard, that resembled a derrick. -He could have stepped over the house; but the girl was not -hypercritical; she was satisfied with the monster, and whispered: - -"It's a beautiful man--now make me coming along." - -Tom drew an hour-glass with a full moon and straw limbs to it and -armed the spreading fingers with a portentous fan. The girl said: - -"It's ever so nice--I wish I could draw." - -"It's easy," whispered Tom, "I'll learn you." - -"Oh, will you? When?" - -"At noon. Do you go home to dinner?" - -"I'll stay if you will." - -"Good--that's a whack. What's your name?" - -"Becky Thatcher. What's yours? Oh, I know. It's Thomas Sawyer." - -"That's the name they lick me by. I'm Tom when I'm good. You call me -Tom, will you?" - -"Yes." - -Now Tom began to scrawl something on the slate, hiding the words from -the girl. But she was not backward this time. She begged to see. Tom -said: - -"Oh, it ain't anything." - -"Yes it is." - -"No it ain't. You don't want to see." - -"Yes I do, indeed I do. Please let me." - -"You'll tell." - -"No I won't--deed and deed and double deed won't." - -"You won't tell anybody at all? Ever, as long as you live?" - -"No, I won't ever tell ANYbody. Now let me." - -"Oh, YOU don't want to see!" - -"Now that you treat me so, I WILL see." And she put her small hand -upon his and a little scuffle ensued, Tom pretending to resist in -earnest but letting his hand slip by degrees till these words were -revealed: "I LOVE YOU." - -"Oh, you bad thing!" And she hit his hand a smart rap, but reddened -and looked pleased, nevertheless. - -Just at this juncture the boy felt a slow, fateful grip closing on his -ear, and a steady lifting impulse. In that wise he was borne across the -house and deposited in his own seat, under a peppering fire of giggles -from the whole school. Then the master stood over him during a few -awful moments, and finally moved away to his throne without saying a -word. But although Tom's ear tingled, his heart was jubilant. - -As the school quieted down Tom made an honest effort to study, but the -turmoil within him was too great. In turn he took his place in the -reading class and made a botch of it; then in the geography class and -turned lakes into mountains, mountains into rivers, and rivers into -continents, till chaos was come again; then in the spelling class, and -got "turned down," by a succession of mere baby words, till he brought -up at the foot and yielded up the pewter medal which he had worn with -ostentation for months. - - - -CHAPTER VII - -THE harder Tom tried to fasten his mind on his book, the more his -ideas wandered. So at last, with a sigh and a yawn, he gave it up. It -seemed to him that the noon recess would never come. The air was -utterly dead. There was not a breath stirring. It was the sleepiest of -sleepy days. The drowsing murmur of the five and twenty studying -scholars soothed the soul like the spell that is in the murmur of bees. -Away off in the flaming sunshine, Cardiff Hill lifted its soft green -sides through a shimmering veil of heat, tinted with the purple of -distance; a few birds floated on lazy wing high in the air; no other -living thing was visible but some cows, and they were asleep. Tom's -heart ached to be free, or else to have something of interest to do to -pass the dreary time. His hand wandered into his pocket and his face -lit up with a glow of gratitude that was prayer, though he did not know -it. Then furtively the percussion-cap box came out. He released the -tick and put him on the long flat desk. The creature probably glowed -with a gratitude that amounted to prayer, too, at this moment, but it -was premature: for when he started thankfully to travel off, Tom turned -him aside with a pin and made him take a new direction. - -Tom's bosom friend sat next him, suffering just as Tom had been, and -now he was deeply and gratefully interested in this entertainment in an -instant. This bosom friend was Joe Harper. The two boys were sworn -friends all the week, and embattled enemies on Saturdays. Joe took a -pin out of his lapel and began to assist in exercising the prisoner. -The sport grew in interest momently. Soon Tom said that they were -interfering with each other, and neither getting the fullest benefit of -the tick. So he put Joe's slate on the desk and drew a line down the -middle of it from top to bottom. - -"Now," said he, "as long as he is on your side you can stir him up and -I'll let him alone; but if you let him get away and get on my side, -you're to leave him alone as long as I can keep him from crossing over." - -"All right, go ahead; start him up." - -The tick escaped from Tom, presently, and crossed the equator. Joe -harassed him awhile, and then he got away and crossed back again. This -change of base occurred often. While one boy was worrying the tick with -absorbing interest, the other would look on with interest as strong, -the two heads bowed together over the slate, and the two souls dead to -all things else. At last luck seemed to settle and abide with Joe. The -tick tried this, that, and the other course, and got as excited and as -anxious as the boys themselves, but time and again just as he would -have victory in his very grasp, so to speak, and Tom's fingers would be -twitching to begin, Joe's pin would deftly head him off, and keep -possession. At last Tom could stand it no longer. The temptation was -too strong. So he reached out and lent a hand with his pin. Joe was -angry in a moment. Said he: - -"Tom, you let him alone." - -"I only just want to stir him up a little, Joe." - -"No, sir, it ain't fair; you just let him alone." - -"Blame it, I ain't going to stir him much." - -"Let him alone, I tell you." - -"I won't!" - -"You shall--he's on my side of the line." - -"Look here, Joe Harper, whose is that tick?" - -"I don't care whose tick he is--he's on my side of the line, and you -sha'n't touch him." - -"Well, I'll just bet I will, though. He's my tick and I'll do what I -blame please with him, or die!" - -A tremendous whack came down on Tom's shoulders, and its duplicate on -Joe's; and for the space of two minutes the dust continued to fly from -the two jackets and the whole school to enjoy it. The boys had been too -absorbed to notice the hush that had stolen upon the school awhile -before when the master came tiptoeing down the room and stood over -them. He had contemplated a good part of the performance before he -contributed his bit of variety to it. - -When school broke up at noon, Tom flew to Becky Thatcher, and -whispered in her ear: - -"Put on your bonnet and let on you're going home; and when you get to -the corner, give the rest of 'em the slip, and turn down through the -lane and come back. I'll go the other way and come it over 'em the same -way." - -So the one went off with one group of scholars, and the other with -another. In a little while the two met at the bottom of the lane, and -when they reached the school they had it all to themselves. Then they -sat together, with a slate before them, and Tom gave Becky the pencil -and held her hand in his, guiding it, and so created another surprising -house. When the interest in art began to wane, the two fell to talking. -Tom was swimming in bliss. He said: - -"Do you love rats?" - -"No! I hate them!" - -"Well, I do, too--LIVE ones. But I mean dead ones, to swing round your -head with a string." - -"No, I don't care for rats much, anyway. What I like is chewing-gum." - -"Oh, I should say so! I wish I had some now." - -"Do you? I've got some. I'll let you chew it awhile, but you must give -it back to me." - -That was agreeable, so they chewed it turn about, and dangled their -legs against the bench in excess of contentment. - -"Was you ever at a circus?" said Tom. - -"Yes, and my pa's going to take me again some time, if I'm good." - -"I been to the circus three or four times--lots of times. Church ain't -shucks to a circus. There's things going on at a circus all the time. -I'm going to be a clown in a circus when I grow up." - -"Oh, are you! That will be nice. They're so lovely, all spotted up." - -"Yes, that's so. And they get slathers of money--most a dollar a day, -Ben Rogers says. Say, Becky, was you ever engaged?" - -"What's that?" - -"Why, engaged to be married." - -"No." - -"Would you like to?" - -"I reckon so. I don't know. What is it like?" - -"Like? Why it ain't like anything. You only just tell a boy you won't -ever have anybody but him, ever ever ever, and then you kiss and that's -all. Anybody can do it." - -"Kiss? What do you kiss for?" - -"Why, that, you know, is to--well, they always do that." - -"Everybody?" - -"Why, yes, everybody that's in love with each other. Do you remember -what I wrote on the slate?" - -"Ye--yes." - -"What was it?" - -"I sha'n't tell you." - -"Shall I tell YOU?" - -"Ye--yes--but some other time." - -"No, now." - -"No, not now--to-morrow." - -"Oh, no, NOW. Please, Becky--I'll whisper it, I'll whisper it ever so -easy." - -Becky hesitating, Tom took silence for consent, and passed his arm -about her waist and whispered the tale ever so softly, with his mouth -close to her ear. And then he added: - -"Now you whisper it to me--just the same." - -She resisted, for a while, and then said: - -"You turn your face away so you can't see, and then I will. But you -mustn't ever tell anybody--WILL you, Tom? Now you won't, WILL you?" - -"No, indeed, indeed I won't. Now, Becky." - -He turned his face away. She bent timidly around till her breath -stirred his curls and whispered, "I--love--you!" - -Then she sprang away and ran around and around the desks and benches, -with Tom after her, and took refuge in a corner at last, with her -little white apron to her face. Tom clasped her about her neck and -pleaded: - -"Now, Becky, it's all done--all over but the kiss. Don't you be afraid -of that--it ain't anything at all. Please, Becky." And he tugged at her -apron and the hands. - -By and by she gave up, and let her hands drop; her face, all glowing -with the struggle, came up and submitted. Tom kissed the red lips and -said: - -"Now it's all done, Becky. And always after this, you know, you ain't -ever to love anybody but me, and you ain't ever to marry anybody but -me, ever never and forever. Will you?" - -"No, I'll never love anybody but you, Tom, and I'll never marry -anybody but you--and you ain't to ever marry anybody but me, either." - -"Certainly. Of course. That's PART of it. And always coming to school -or when we're going home, you're to walk with me, when there ain't -anybody looking--and you choose me and I choose you at parties, because -that's the way you do when you're engaged." - -"It's so nice. I never heard of it before." - -"Oh, it's ever so gay! Why, me and Amy Lawrence--" - -The big eyes told Tom his blunder and he stopped, confused. - -"Oh, Tom! Then I ain't the first you've ever been engaged to!" - -The child began to cry. Tom said: - -"Oh, don't cry, Becky, I don't care for her any more." - -"Yes, you do, Tom--you know you do." - -Tom tried to put his arm about her neck, but she pushed him away and -turned her face to the wall, and went on crying. Tom tried again, with -soothing words in his mouth, and was repulsed again. Then his pride was -up, and he strode away and went outside. He stood about, restless and -uneasy, for a while, glancing at the door, every now and then, hoping -she would repent and come to find him. But she did not. Then he began -to feel badly and fear that he was in the wrong. It was a hard struggle -with him to make new advances, now, but he nerved himself to it and -entered. She was still standing back there in the corner, sobbing, with -her face to the wall. Tom's heart smote him. He went to her and stood a -moment, not knowing exactly how to proceed. Then he said hesitatingly: - -"Becky, I--I don't care for anybody but you." - -No reply--but sobs. - -"Becky"--pleadingly. "Becky, won't you say something?" - -More sobs. - -Tom got out his chiefest jewel, a brass knob from the top of an -andiron, and passed it around her so that she could see it, and said: - -"Please, Becky, won't you take it?" - -She struck it to the floor. Then Tom marched out of the house and over -the hills and far away, to return to school no more that day. Presently -Becky began to suspect. She ran to the door; he was not in sight; she -flew around to the play-yard; he was not there. Then she called: - -"Tom! Come back, Tom!" - -She listened intently, but there was no answer. She had no companions -but silence and loneliness. So she sat down to cry again and upbraid -herself; and by this time the scholars began to gather again, and she -had to hide her griefs and still her broken heart and take up the cross -of a long, dreary, aching afternoon, with none among the strangers -about her to exchange sorrows with. - - - -CHAPTER VIII - -TOM dodged hither and thither through lanes until he was well out of -the track of returning scholars, and then fell into a moody jog. He -crossed a small "branch" two or three times, because of a prevailing -juvenile superstition that to cross water baffled pursuit. Half an hour -later he was disappearing behind the Douglas mansion on the summit of -Cardiff Hill, and the schoolhouse was hardly distinguishable away off -in the valley behind him. He entered a dense wood, picked his pathless -way to the centre of it, and sat down on a mossy spot under a spreading -oak. There was not even a zephyr stirring; the dead noonday heat had -even stilled the songs of the birds; nature lay in a trance that was -broken by no sound but the occasional far-off hammering of a -woodpecker, and this seemed to render the pervading silence and sense -of loneliness the more profound. The boy's soul was steeped in -melancholy; his feelings were in happy accord with his surroundings. He -sat long with his elbows on his knees and his chin in his hands, -meditating. It seemed to him that life was but a trouble, at best, and -he more than half envied Jimmy Hodges, so lately released; it must be -very peaceful, he thought, to lie and slumber and dream forever and -ever, with the wind whispering through the trees and caressing the -grass and the flowers over the grave, and nothing to bother and grieve -about, ever any more. If he only had a clean Sunday-school record he -could be willing to go, and be done with it all. Now as to this girl. -What had he done? Nothing. He had meant the best in the world, and been -treated like a dog--like a very dog. She would be sorry some day--maybe -when it was too late. Ah, if he could only die TEMPORARILY! - -But the elastic heart of youth cannot be compressed into one -constrained shape long at a time. Tom presently began to drift -insensibly back into the concerns of this life again. What if he turned -his back, now, and disappeared mysteriously? What if he went away--ever -so far away, into unknown countries beyond the seas--and never came -back any more! How would she feel then! The idea of being a clown -recurred to him now, only to fill him with disgust. For frivolity and -jokes and spotted tights were an offense, when they intruded themselves -upon a spirit that was exalted into the vague august realm of the -romantic. No, he would be a soldier, and return after long years, all -war-worn and illustrious. No--better still, he would join the Indians, -and hunt buffaloes and go on the warpath in the mountain ranges and the -trackless great plains of the Far West, and away in the future come -back a great chief, bristling with feathers, hideous with paint, and -prance into Sunday-school, some drowsy summer morning, with a -bloodcurdling war-whoop, and sear the eyeballs of all his companions -with unappeasable envy. But no, there was something gaudier even than -this. He would be a pirate! That was it! NOW his future lay plain -before him, and glowing with unimaginable splendor. How his name would -fill the world, and make people shudder! How gloriously he would go -plowing the dancing seas, in his long, low, black-hulled racer, the -Spirit of the Storm, with his grisly flag flying at the fore! And at -the zenith of his fame, how he would suddenly appear at the old village -and stalk into church, brown and weather-beaten, in his black velvet -doublet and trunks, his great jack-boots, his crimson sash, his belt -bristling with horse-pistols, his crime-rusted cutlass at his side, his -slouch hat with waving plumes, his black flag unfurled, with the skull -and crossbones on it, and hear with swelling ecstasy the whisperings, -"It's Tom Sawyer the Pirate!--the Black Avenger of the Spanish Main!" - -Yes, it was settled; his career was determined. He would run away from -home and enter upon it. He would start the very next morning. Therefore -he must now begin to get ready. He would collect his resources -together. He went to a rotten log near at hand and began to dig under -one end of it with his Barlow knife. He soon struck wood that sounded -hollow. He put his hand there and uttered this incantation impressively: - -"What hasn't come here, come! What's here, stay here!" - -Then he scraped away the dirt, and exposed a pine shingle. He took it -up and disclosed a shapely little treasure-house whose bottom and sides -were of shingles. In it lay a marble. Tom's astonishment was boundless! -He scratched his head with a perplexed air, and said: - -"Well, that beats anything!" - -Then he tossed the marble away pettishly, and stood cogitating. The -truth was, that a superstition of his had failed, here, which he and -all his comrades had always looked upon as infallible. If you buried a -marble with certain necessary incantations, and left it alone a -fortnight, and then opened the place with the incantation he had just -used, you would find that all the marbles you had ever lost had -gathered themselves together there, meantime, no matter how widely they -had been separated. But now, this thing had actually and unquestionably -failed. Tom's whole structure of faith was shaken to its foundations. -He had many a time heard of this thing succeeding but never of its -failing before. It did not occur to him that he had tried it several -times before, himself, but could never find the hiding-places -afterward. He puzzled over the matter some time, and finally decided -that some witch had interfered and broken the charm. He thought he -would satisfy himself on that point; so he searched around till he -found a small sandy spot with a little funnel-shaped depression in it. -He laid himself down and put his mouth close to this depression and -called-- - -"Doodle-bug, doodle-bug, tell me what I want to know! Doodle-bug, -doodle-bug, tell me what I want to know!" - -The sand began to work, and presently a small black bug appeared for a -second and then darted under again in a fright. - -"He dasn't tell! So it WAS a witch that done it. I just knowed it." - -He well knew the futility of trying to contend against witches, so he -gave up discouraged. But it occurred to him that he might as well have -the marble he had just thrown away, and therefore he went and made a -patient search for it. But he could not find it. Now he went back to -his treasure-house and carefully placed himself just as he had been -standing when he tossed the marble away; then he took another marble -from his pocket and tossed it in the same way, saying: - -"Brother, go find your brother!" - -He watched where it stopped, and went there and looked. But it must -have fallen short or gone too far; so he tried twice more. The last -repetition was successful. The two marbles lay within a foot of each -other. - -Just here the blast of a toy tin trumpet came faintly down the green -aisles of the forest. Tom flung off his jacket and trousers, turned a -suspender into a belt, raked away some brush behind the rotten log, -disclosing a rude bow and arrow, a lath sword and a tin trumpet, and in -a moment had seized these things and bounded away, barelegged, with -fluttering shirt. He presently halted under a great elm, blew an -answering blast, and then began to tiptoe and look warily out, this way -and that. He said cautiously--to an imaginary company: - -"Hold, my merry men! Keep hid till I blow." - -Now appeared Joe Harper, as airily clad and elaborately armed as Tom. -Tom called: - -"Hold! Who comes here into Sherwood Forest without my pass?" - -"Guy of Guisborne wants no man's pass. Who art thou that--that--" - -"Dares to hold such language," said Tom, prompting--for they talked -"by the book," from memory. - -"Who art thou that dares to hold such language?" - -"I, indeed! I am Robin Hood, as thy caitiff carcase soon shall know." - -"Then art thou indeed that famous outlaw? Right gladly will I dispute -with thee the passes of the merry wood. Have at thee!" - -They took their lath swords, dumped their other traps on the ground, -struck a fencing attitude, foot to foot, and began a grave, careful -combat, "two up and two down." Presently Tom said: - -"Now, if you've got the hang, go it lively!" - -So they "went it lively," panting and perspiring with the work. By and -by Tom shouted: - -"Fall! fall! Why don't you fall?" - -"I sha'n't! Why don't you fall yourself? You're getting the worst of -it." - -"Why, that ain't anything. I can't fall; that ain't the way it is in -the book. The book says, 'Then with one back-handed stroke he slew poor -Guy of Guisborne.' You're to turn around and let me hit you in the -back." - -There was no getting around the authorities, so Joe turned, received -the whack and fell. - -"Now," said Joe, getting up, "you got to let me kill YOU. That's fair." - -"Why, I can't do that, it ain't in the book." - -"Well, it's blamed mean--that's all." - -"Well, say, Joe, you can be Friar Tuck or Much the miller's son, and -lam me with a quarter-staff; or I'll be the Sheriff of Nottingham and -you be Robin Hood a little while and kill me." - -This was satisfactory, and so these adventures were carried out. Then -Tom became Robin Hood again, and was allowed by the treacherous nun to -bleed his strength away through his neglected wound. And at last Joe, -representing a whole tribe of weeping outlaws, dragged him sadly forth, -gave his bow into his feeble hands, and Tom said, "Where this arrow -falls, there bury poor Robin Hood under the greenwood tree." Then he -shot the arrow and fell back and would have died, but he lit on a -nettle and sprang up too gaily for a corpse. - -The boys dressed themselves, hid their accoutrements, and went off -grieving that there were no outlaws any more, and wondering what modern -civilization could claim to have done to compensate for their loss. -They said they would rather be outlaws a year in Sherwood Forest than -President of the United States forever. - - - -CHAPTER IX - -AT half-past nine, that night, Tom and Sid were sent to bed, as usual. -They said their prayers, and Sid was soon asleep. Tom lay awake and -waited, in restless impatience. When it seemed to him that it must be -nearly daylight, he heard the clock strike ten! This was despair. He -would have tossed and fidgeted, as his nerves demanded, but he was -afraid he might wake Sid. So he lay still, and stared up into the dark. -Everything was dismally still. By and by, out of the stillness, little, -scarcely perceptible noises began to emphasize themselves. The ticking -of the clock began to bring itself into notice. Old beams began to -crack mysteriously. The stairs creaked faintly. Evidently spirits were -abroad. A measured, muffled snore issued from Aunt Polly's chamber. And -now the tiresome chirping of a cricket that no human ingenuity could -locate, began. Next the ghastly ticking of a deathwatch in the wall at -the bed's head made Tom shudder--it meant that somebody's days were -numbered. Then the howl of a far-off dog rose on the night air, and was -answered by a fainter howl from a remoter distance. Tom was in an -agony. At last he was satisfied that time had ceased and eternity -begun; he began to doze, in spite of himself; the clock chimed eleven, -but he did not hear it. And then there came, mingling with his -half-formed dreams, a most melancholy caterwauling. The raising of a -neighboring window disturbed him. A cry of "Scat! you devil!" and the -crash of an empty bottle against the back of his aunt's woodshed -brought him wide awake, and a single minute later he was dressed and -out of the window and creeping along the roof of the "ell" on all -fours. He "meow'd" with caution once or twice, as he went; then jumped -to the roof of the woodshed and thence to the ground. Huckleberry Finn -was there, with his dead cat. The boys moved off and disappeared in the -gloom. At the end of half an hour they were wading through the tall -grass of the graveyard. - -It was a graveyard of the old-fashioned Western kind. It was on a -hill, about a mile and a half from the village. It had a crazy board -fence around it, which leaned inward in places, and outward the rest of -the time, but stood upright nowhere. Grass and weeds grew rank over the -whole cemetery. All the old graves were sunken in, there was not a -tombstone on the place; round-topped, worm-eaten boards staggered over -the graves, leaning for support and finding none. "Sacred to the memory -of" So-and-So had been painted on them once, but it could no longer -have been read, on the most of them, now, even if there had been light. - -A faint wind moaned through the trees, and Tom feared it might be the -spirits of the dead, complaining at being disturbed. The boys talked -little, and only under their breath, for the time and the place and the -pervading solemnity and silence oppressed their spirits. They found the -sharp new heap they were seeking, and ensconced themselves within the -protection of three great elms that grew in a bunch within a few feet -of the grave. - -Then they waited in silence for what seemed a long time. The hooting -of a distant owl was all the sound that troubled the dead stillness. -Tom's reflections grew oppressive. He must force some talk. So he said -in a whisper: - -"Hucky, do you believe the dead people like it for us to be here?" - -Huckleberry whispered: - -"I wisht I knowed. It's awful solemn like, AIN'T it?" - -"I bet it is." - -There was a considerable pause, while the boys canvassed this matter -inwardly. Then Tom whispered: - -"Say, Hucky--do you reckon Hoss Williams hears us talking?" - -"O' course he does. Least his sperrit does." - -Tom, after a pause: - -"I wish I'd said Mister Williams. But I never meant any harm. -Everybody calls him Hoss." - -"A body can't be too partic'lar how they talk 'bout these-yer dead -people, Tom." - -This was a damper, and conversation died again. - -Presently Tom seized his comrade's arm and said: - -"Sh!" - -"What is it, Tom?" And the two clung together with beating hearts. - -"Sh! There 'tis again! Didn't you hear it?" - -"I--" - -"There! Now you hear it." - -"Lord, Tom, they're coming! They're coming, sure. What'll we do?" - -"I dono. Think they'll see us?" - -"Oh, Tom, they can see in the dark, same as cats. I wisht I hadn't -come." - -"Oh, don't be afeard. I don't believe they'll bother us. We ain't -doing any harm. If we keep perfectly still, maybe they won't notice us -at all." - -"I'll try to, Tom, but, Lord, I'm all of a shiver." - -"Listen!" - -The boys bent their heads together and scarcely breathed. A muffled -sound of voices floated up from the far end of the graveyard. - -"Look! See there!" whispered Tom. "What is it?" - -"It's devil-fire. Oh, Tom, this is awful." - -Some vague figures approached through the gloom, swinging an -old-fashioned tin lantern that freckled the ground with innumerable -little spangles of light. Presently Huckleberry whispered with a -shudder: - -"It's the devils sure enough. Three of 'em! Lordy, Tom, we're goners! -Can you pray?" - -"I'll try, but don't you be afeard. They ain't going to hurt us. 'Now -I lay me down to sleep, I--'" - -"Sh!" - -"What is it, Huck?" - -"They're HUMANS! One of 'em is, anyway. One of 'em's old Muff Potter's -voice." - -"No--'tain't so, is it?" - -"I bet I know it. Don't you stir nor budge. He ain't sharp enough to -notice us. Drunk, the same as usual, likely--blamed old rip!" - -"All right, I'll keep still. Now they're stuck. Can't find it. Here -they come again. Now they're hot. Cold again. Hot again. Red hot! -They're p'inted right, this time. Say, Huck, I know another o' them -voices; it's Injun Joe." - -"That's so--that murderin' half-breed! I'd druther they was devils a -dern sight. What kin they be up to?" - -The whisper died wholly out, now, for the three men had reached the -grave and stood within a few feet of the boys' hiding-place. - -"Here it is," said the third voice; and the owner of it held the -lantern up and revealed the face of young Doctor Robinson. - -Potter and Injun Joe were carrying a handbarrow with a rope and a -couple of shovels on it. They cast down their load and began to open -the grave. The doctor put the lantern at the head of the grave and came -and sat down with his back against one of the elm trees. He was so -close the boys could have touched him. - -"Hurry, men!" he said, in a low voice; "the moon might come out at any -moment." - -They growled a response and went on digging. For some time there was -no noise but the grating sound of the spades discharging their freight -of mould and gravel. It was very monotonous. Finally a spade struck -upon the coffin with a dull woody accent, and within another minute or -two the men had hoisted it out on the ground. They pried off the lid -with their shovels, got out the body and dumped it rudely on the -ground. The moon drifted from behind the clouds and exposed the pallid -face. The barrow was got ready and the corpse placed on it, covered -with a blanket, and bound to its place with the rope. Potter took out a -large spring-knife and cut off the dangling end of the rope and then -said: - -"Now the cussed thing's ready, Sawbones, and you'll just out with -another five, or here she stays." - -"That's the talk!" said Injun Joe. - -"Look here, what does this mean?" said the doctor. "You required your -pay in advance, and I've paid you." - -"Yes, and you done more than that," said Injun Joe, approaching the -doctor, who was now standing. "Five years ago you drove me away from -your father's kitchen one night, when I come to ask for something to -eat, and you said I warn't there for any good; and when I swore I'd get -even with you if it took a hundred years, your father had me jailed for -a vagrant. Did you think I'd forget? The Injun blood ain't in me for -nothing. And now I've GOT you, and you got to SETTLE, you know!" - -He was threatening the doctor, with his fist in his face, by this -time. The doctor struck out suddenly and stretched the ruffian on the -ground. Potter dropped his knife, and exclaimed: - -"Here, now, don't you hit my pard!" and the next moment he had -grappled with the doctor and the two were struggling with might and -main, trampling the grass and tearing the ground with their heels. -Injun Joe sprang to his feet, his eyes flaming with passion, snatched -up Potter's knife, and went creeping, catlike and stooping, round and -round about the combatants, seeking an opportunity. All at once the -doctor flung himself free, seized the heavy headboard of Williams' -grave and felled Potter to the earth with it--and in the same instant -the half-breed saw his chance and drove the knife to the hilt in the -young man's breast. He reeled and fell partly upon Potter, flooding him -with his blood, and in the same moment the clouds blotted out the -dreadful spectacle and the two frightened boys went speeding away in -the dark. - -Presently, when the moon emerged again, Injun Joe was standing over -the two forms, contemplating them. The doctor murmured inarticulately, -gave a long gasp or two and was still. The half-breed muttered: - -"THAT score is settled--damn you." - -Then he robbed the body. After which he put the fatal knife in -Potter's open right hand, and sat down on the dismantled coffin. Three ---four--five minutes passed, and then Potter began to stir and moan. His -hand closed upon the knife; he raised it, glanced at it, and let it -fall, with a shudder. Then he sat up, pushing the body from him, and -gazed at it, and then around him, confusedly. His eyes met Joe's. - -"Lord, how is this, Joe?" he said. - -"It's a dirty business," said Joe, without moving. - -"What did you do it for?" - -"I! I never done it!" - -"Look here! That kind of talk won't wash." - -Potter trembled and grew white. - -"I thought I'd got sober. I'd no business to drink to-night. But it's -in my head yet--worse'n when we started here. I'm all in a muddle; -can't recollect anything of it, hardly. Tell me, Joe--HONEST, now, old -feller--did I do it? Joe, I never meant to--'pon my soul and honor, I -never meant to, Joe. Tell me how it was, Joe. Oh, it's awful--and him -so young and promising." - -"Why, you two was scuffling, and he fetched you one with the headboard -and you fell flat; and then up you come, all reeling and staggering -like, and snatched the knife and jammed it into him, just as he fetched -you another awful clip--and here you've laid, as dead as a wedge til -now." - -"Oh, I didn't know what I was a-doing. I wish I may die this minute if -I did. It was all on account of the whiskey and the excitement, I -reckon. I never used a weepon in my life before, Joe. I've fought, but -never with weepons. They'll all say that. Joe, don't tell! Say you -won't tell, Joe--that's a good feller. I always liked you, Joe, and -stood up for you, too. Don't you remember? You WON'T tell, WILL you, -Joe?" And the poor creature dropped on his knees before the stolid -murderer, and clasped his appealing hands. - -"No, you've always been fair and square with me, Muff Potter, and I -won't go back on you. There, now, that's as fair as a man can say." - -"Oh, Joe, you're an angel. I'll bless you for this the longest day I -live." And Potter began to cry. - -"Come, now, that's enough of that. This ain't any time for blubbering. -You be off yonder way and I'll go this. Move, now, and don't leave any -tracks behind you." - -Potter started on a trot that quickly increased to a run. The -half-breed stood looking after him. He muttered: - -"If he's as much stunned with the lick and fuddled with the rum as he -had the look of being, he won't think of the knife till he's gone so -far he'll be afraid to come back after it to such a place by himself ---chicken-heart!" - -Two or three minutes later the murdered man, the blanketed corpse, the -lidless coffin, and the open grave were under no inspection but the -moon's. The stillness was complete again, too. - - - -CHAPTER X - -THE two boys flew on and on, toward the village, speechless with -horror. They glanced backward over their shoulders from time to time, -apprehensively, as if they feared they might be followed. Every stump -that started up in their path seemed a man and an enemy, and made them -catch their breath; and as they sped by some outlying cottages that lay -near the village, the barking of the aroused watch-dogs seemed to give -wings to their feet. - -"If we can only get to the old tannery before we break down!" -whispered Tom, in short catches between breaths. "I can't stand it much -longer." - -Huckleberry's hard pantings were his only reply, and the boys fixed -their eyes on the goal of their hopes and bent to their work to win it. -They gained steadily on it, and at last, breast to breast, they burst -through the open door and fell grateful and exhausted in the sheltering -shadows beyond. By and by their pulses slowed down, and Tom whispered: - -"Huckleberry, what do you reckon'll come of this?" - -"If Doctor Robinson dies, I reckon hanging'll come of it." - -"Do you though?" - -"Why, I KNOW it, Tom." - -Tom thought a while, then he said: - -"Who'll tell? We?" - -"What are you talking about? S'pose something happened and Injun Joe -DIDN'T hang? Why, he'd kill us some time or other, just as dead sure as -we're a laying here." - -"That's just what I was thinking to myself, Huck." - -"If anybody tells, let Muff Potter do it, if he's fool enough. He's -generally drunk enough." - -Tom said nothing--went on thinking. Presently he whispered: - -"Huck, Muff Potter don't know it. How can he tell?" - -"What's the reason he don't know it?" - -"Because he'd just got that whack when Injun Joe done it. D'you reckon -he could see anything? D'you reckon he knowed anything?" - -"By hokey, that's so, Tom!" - -"And besides, look-a-here--maybe that whack done for HIM!" - -"No, 'taint likely, Tom. He had liquor in him; I could see that; and -besides, he always has. Well, when pap's full, you might take and belt -him over the head with a church and you couldn't phase him. He says so, -his own self. So it's the same with Muff Potter, of course. But if a -man was dead sober, I reckon maybe that whack might fetch him; I dono." - -After another reflective silence, Tom said: - -"Hucky, you sure you can keep mum?" - -"Tom, we GOT to keep mum. You know that. That Injun devil wouldn't -make any more of drownding us than a couple of cats, if we was to -squeak 'bout this and they didn't hang him. Now, look-a-here, Tom, less -take and swear to one another--that's what we got to do--swear to keep -mum." - -"I'm agreed. It's the best thing. Would you just hold hands and swear -that we--" - -"Oh no, that wouldn't do for this. That's good enough for little -rubbishy common things--specially with gals, cuz THEY go back on you -anyway, and blab if they get in a huff--but there orter be writing -'bout a big thing like this. And blood." - -Tom's whole being applauded this idea. It was deep, and dark, and -awful; the hour, the circumstances, the surroundings, were in keeping -with it. He picked up a clean pine shingle that lay in the moonlight, -took a little fragment of "red keel" out of his pocket, got the moon on -his work, and painfully scrawled these lines, emphasizing each slow -down-stroke by clamping his tongue between his teeth, and letting up -the pressure on the up-strokes. [See next page.] - - "Huck Finn and - Tom Sawyer swears - they will keep mum - about This and They - wish They may Drop - down dead in Their - Tracks if They ever - Tell and Rot." - -Huckleberry was filled with admiration of Tom's facility in writing, -and the sublimity of his language. He at once took a pin from his lapel -and was going to prick his flesh, but Tom said: - -"Hold on! Don't do that. A pin's brass. It might have verdigrease on -it." - -"What's verdigrease?" - -"It's p'ison. That's what it is. You just swaller some of it once ---you'll see." - -So Tom unwound the thread from one of his needles, and each boy -pricked the ball of his thumb and squeezed out a drop of blood. In -time, after many squeezes, Tom managed to sign his initials, using the -ball of his little finger for a pen. Then he showed Huckleberry how to -make an H and an F, and the oath was complete. They buried the shingle -close to the wall, with some dismal ceremonies and incantations, and -the fetters that bound their tongues were considered to be locked and -the key thrown away. - -A figure crept stealthily through a break in the other end of the -ruined building, now, but they did not notice it. - -"Tom," whispered Huckleberry, "does this keep us from EVER telling ---ALWAYS?" - -"Of course it does. It don't make any difference WHAT happens, we got -to keep mum. We'd drop down dead--don't YOU know that?" - -"Yes, I reckon that's so." - -They continued to whisper for some little time. Presently a dog set up -a long, lugubrious howl just outside--within ten feet of them. The boys -clasped each other suddenly, in an agony of fright. - -"Which of us does he mean?" gasped Huckleberry. - -"I dono--peep through the crack. Quick!" - -"No, YOU, Tom!" - -"I can't--I can't DO it, Huck!" - -"Please, Tom. There 'tis again!" - -"Oh, lordy, I'm thankful!" whispered Tom. "I know his voice. It's Bull -Harbison." * - -[* If Mr. Harbison owned a slave named Bull, Tom would have spoken of -him as "Harbison's Bull," but a son or a dog of that name was "Bull -Harbison."] - -"Oh, that's good--I tell you, Tom, I was most scared to death; I'd a -bet anything it was a STRAY dog." - -The dog howled again. The boys' hearts sank once more. - -"Oh, my! that ain't no Bull Harbison!" whispered Huckleberry. "DO, Tom!" - -Tom, quaking with fear, yielded, and put his eye to the crack. His -whisper was hardly audible when he said: - -"Oh, Huck, IT S A STRAY DOG!" - -"Quick, Tom, quick! Who does he mean?" - -"Huck, he must mean us both--we're right together." - -"Oh, Tom, I reckon we're goners. I reckon there ain't no mistake 'bout -where I'LL go to. I been so wicked." - -"Dad fetch it! This comes of playing hookey and doing everything a -feller's told NOT to do. I might a been good, like Sid, if I'd a tried ---but no, I wouldn't, of course. But if ever I get off this time, I lay -I'll just WALLER in Sunday-schools!" And Tom began to snuffle a little. - -"YOU bad!" and Huckleberry began to snuffle too. "Consound it, Tom -Sawyer, you're just old pie, 'longside o' what I am. Oh, LORDY, lordy, -lordy, I wisht I only had half your chance." - -Tom choked off and whispered: - -"Look, Hucky, look! He's got his BACK to us!" - -Hucky looked, with joy in his heart. - -"Well, he has, by jingoes! Did he before?" - -"Yes, he did. But I, like a fool, never thought. Oh, this is bully, -you know. NOW who can he mean?" - -The howling stopped. Tom pricked up his ears. - -"Sh! What's that?" he whispered. - -"Sounds like--like hogs grunting. No--it's somebody snoring, Tom." - -"That IS it! Where 'bouts is it, Huck?" - -"I bleeve it's down at 'tother end. Sounds so, anyway. Pap used to -sleep there, sometimes, 'long with the hogs, but laws bless you, he -just lifts things when HE snores. Besides, I reckon he ain't ever -coming back to this town any more." - -The spirit of adventure rose in the boys' souls once more. - -"Hucky, do you das't to go if I lead?" - -"I don't like to, much. Tom, s'pose it's Injun Joe!" - -Tom quailed. But presently the temptation rose up strong again and the -boys agreed to try, with the understanding that they would take to -their heels if the snoring stopped. So they went tiptoeing stealthily -down, the one behind the other. When they had got to within five steps -of the snorer, Tom stepped on a stick, and it broke with a sharp snap. -The man moaned, writhed a little, and his face came into the moonlight. -It was Muff Potter. The boys' hearts had stood still, and their hopes -too, when the man moved, but their fears passed away now. They tiptoed -out, through the broken weather-boarding, and stopped at a little -distance to exchange a parting word. That long, lugubrious howl rose on -the night air again! They turned and saw the strange dog standing -within a few feet of where Potter was lying, and FACING Potter, with -his nose pointing heavenward. - -"Oh, geeminy, it's HIM!" exclaimed both boys, in a breath. - -"Say, Tom--they say a stray dog come howling around Johnny Miller's -house, 'bout midnight, as much as two weeks ago; and a whippoorwill -come in and lit on the banisters and sung, the very same evening; and -there ain't anybody dead there yet." - -"Well, I know that. And suppose there ain't. Didn't Gracie Miller fall -in the kitchen fire and burn herself terrible the very next Saturday?" - -"Yes, but she ain't DEAD. And what's more, she's getting better, too." - -"All right, you wait and see. She's a goner, just as dead sure as Muff -Potter's a goner. That's what the niggers say, and they know all about -these kind of things, Huck." - -Then they separated, cogitating. When Tom crept in at his bedroom -window the night was almost spent. He undressed with excessive caution, -and fell asleep congratulating himself that nobody knew of his -escapade. He was not aware that the gently-snoring Sid was awake, and -had been so for an hour. - -When Tom awoke, Sid was dressed and gone. There was a late look in the -light, a late sense in the atmosphere. He was startled. Why had he not -been called--persecuted till he was up, as usual? The thought filled -him with bodings. Within five minutes he was dressed and down-stairs, -feeling sore and drowsy. The family were still at table, but they had -finished breakfast. There was no voice of rebuke; but there were -averted eyes; there was a silence and an air of solemnity that struck a -chill to the culprit's heart. He sat down and tried to seem gay, but it -was up-hill work; it roused no smile, no response, and he lapsed into -silence and let his heart sink down to the depths. - -After breakfast his aunt took him aside, and Tom almost brightened in -the hope that he was going to be flogged; but it was not so. His aunt -wept over him and asked him how he could go and break her old heart so; -and finally told him to go on, and ruin himself and bring her gray -hairs with sorrow to the grave, for it was no use for her to try any -more. This was worse than a thousand whippings, and Tom's heart was -sorer now than his body. He cried, he pleaded for forgiveness, promised -to reform over and over again, and then received his dismissal, feeling -that he had won but an imperfect forgiveness and established but a -feeble confidence. - -He left the presence too miserable to even feel revengeful toward Sid; -and so the latter's prompt retreat through the back gate was -unnecessary. He moped to school gloomy and sad, and took his flogging, -along with Joe Harper, for playing hookey the day before, with the air -of one whose heart was busy with heavier woes and wholly dead to -trifles. Then he betook himself to his seat, rested his elbows on his -desk and his jaws in his hands, and stared at the wall with the stony -stare of suffering that has reached the limit and can no further go. -His elbow was pressing against some hard substance. After a long time -he slowly and sadly changed his position, and took up this object with -a sigh. It was in a paper. He unrolled it. A long, lingering, colossal -sigh followed, and his heart broke. It was his brass andiron knob! - -This final feather broke the camel's back. - - - -CHAPTER XI - -CLOSE upon the hour of noon the whole village was suddenly electrified -with the ghastly news. No need of the as yet undreamed-of telegraph; -the tale flew from man to man, from group to group, from house to -house, with little less than telegraphic speed. Of course the -schoolmaster gave holiday for that afternoon; the town would have -thought strangely of him if he had not. - -A gory knife had been found close to the murdered man, and it had been -recognized by somebody as belonging to Muff Potter--so the story ran. -And it was said that a belated citizen had come upon Potter washing -himself in the "branch" about one or two o'clock in the morning, and -that Potter had at once sneaked off--suspicious circumstances, -especially the washing which was not a habit with Potter. It was also -said that the town had been ransacked for this "murderer" (the public -are not slow in the matter of sifting evidence and arriving at a -verdict), but that he could not be found. Horsemen had departed down -all the roads in every direction, and the Sheriff "was confident" that -he would be captured before night. - -All the town was drifting toward the graveyard. Tom's heartbreak -vanished and he joined the procession, not because he would not a -thousand times rather go anywhere else, but because an awful, -unaccountable fascination drew him on. Arrived at the dreadful place, -he wormed his small body through the crowd and saw the dismal -spectacle. It seemed to him an age since he was there before. Somebody -pinched his arm. He turned, and his eyes met Huckleberry's. Then both -looked elsewhere at once, and wondered if anybody had noticed anything -in their mutual glance. But everybody was talking, and intent upon the -grisly spectacle before them. - -"Poor fellow!" "Poor young fellow!" "This ought to be a lesson to -grave robbers!" "Muff Potter'll hang for this if they catch him!" This -was the drift of remark; and the minister said, "It was a judgment; His -hand is here." - -Now Tom shivered from head to heel; for his eye fell upon the stolid -face of Injun Joe. At this moment the crowd began to sway and struggle, -and voices shouted, "It's him! it's him! he's coming himself!" - -"Who? Who?" from twenty voices. - -"Muff Potter!" - -"Hallo, he's stopped!--Look out, he's turning! Don't let him get away!" - -People in the branches of the trees over Tom's head said he wasn't -trying to get away--he only looked doubtful and perplexed. - -"Infernal impudence!" said a bystander; "wanted to come and take a -quiet look at his work, I reckon--didn't expect any company." - -The crowd fell apart, now, and the Sheriff came through, -ostentatiously leading Potter by the arm. The poor fellow's face was -haggard, and his eyes showed the fear that was upon him. When he stood -before the murdered man, he shook as with a palsy, and he put his face -in his hands and burst into tears. - -"I didn't do it, friends," he sobbed; "'pon my word and honor I never -done it." - -"Who's accused you?" shouted a voice. - -This shot seemed to carry home. Potter lifted his face and looked -around him with a pathetic hopelessness in his eyes. He saw Injun Joe, -and exclaimed: - -"Oh, Injun Joe, you promised me you'd never--" - -"Is that your knife?" and it was thrust before him by the Sheriff. - -Potter would have fallen if they had not caught him and eased him to -the ground. Then he said: - -"Something told me 't if I didn't come back and get--" He shuddered; -then waved his nerveless hand with a vanquished gesture and said, "Tell -'em, Joe, tell 'em--it ain't any use any more." - -Then Huckleberry and Tom stood dumb and staring, and heard the -stony-hearted liar reel off his serene statement, they expecting every -moment that the clear sky would deliver God's lightnings upon his head, -and wondering to see how long the stroke was delayed. And when he had -finished and still stood alive and whole, their wavering impulse to -break their oath and save the poor betrayed prisoner's life faded and -vanished away, for plainly this miscreant had sold himself to Satan and -it would be fatal to meddle with the property of such a power as that. - -"Why didn't you leave? What did you want to come here for?" somebody -said. - -"I couldn't help it--I couldn't help it," Potter moaned. "I wanted to -run away, but I couldn't seem to come anywhere but here." And he fell -to sobbing again. - -Injun Joe repeated his statement, just as calmly, a few minutes -afterward on the inquest, under oath; and the boys, seeing that the -lightnings were still withheld, were confirmed in their belief that Joe -had sold himself to the devil. He was now become, to them, the most -balefully interesting object they had ever looked upon, and they could -not take their fascinated eyes from his face. - -They inwardly resolved to watch him nights, when opportunity should -offer, in the hope of getting a glimpse of his dread master. - -Injun Joe helped to raise the body of the murdered man and put it in a -wagon for removal; and it was whispered through the shuddering crowd -that the wound bled a little! The boys thought that this happy -circumstance would turn suspicion in the right direction; but they were -disappointed, for more than one villager remarked: - -"It was within three feet of Muff Potter when it done it." - -Tom's fearful secret and gnawing conscience disturbed his sleep for as -much as a week after this; and at breakfast one morning Sid said: - -"Tom, you pitch around and talk in your sleep so much that you keep me -awake half the time." - -Tom blanched and dropped his eyes. - -"It's a bad sign," said Aunt Polly, gravely. "What you got on your -mind, Tom?" - -"Nothing. Nothing 't I know of." But the boy's hand shook so that he -spilled his coffee. - -"And you do talk such stuff," Sid said. "Last night you said, 'It's -blood, it's blood, that's what it is!' You said that over and over. And -you said, 'Don't torment me so--I'll tell!' Tell WHAT? What is it -you'll tell?" - -Everything was swimming before Tom. There is no telling what might -have happened, now, but luckily the concern passed out of Aunt Polly's -face and she came to Tom's relief without knowing it. She said: - -"Sho! It's that dreadful murder. I dream about it most every night -myself. Sometimes I dream it's me that done it." - -Mary said she had been affected much the same way. Sid seemed -satisfied. Tom got out of the presence as quick as he plausibly could, -and after that he complained of toothache for a week, and tied up his -jaws every night. He never knew that Sid lay nightly watching, and -frequently slipped the bandage free and then leaned on his elbow -listening a good while at a time, and afterward slipped the bandage -back to its place again. Tom's distress of mind wore off gradually and -the toothache grew irksome and was discarded. If Sid really managed to -make anything out of Tom's disjointed mutterings, he kept it to himself. - -It seemed to Tom that his schoolmates never would get done holding -inquests on dead cats, and thus keeping his trouble present to his -mind. Sid noticed that Tom never was coroner at one of these inquiries, -though it had been his habit to take the lead in all new enterprises; -he noticed, too, that Tom never acted as a witness--and that was -strange; and Sid did not overlook the fact that Tom even showed a -marked aversion to these inquests, and always avoided them when he -could. Sid marvelled, but said nothing. However, even inquests went out -of vogue at last, and ceased to torture Tom's conscience. - -Every day or two, during this time of sorrow, Tom watched his -opportunity and went to the little grated jail-window and smuggled such -small comforts through to the "murderer" as he could get hold of. The -jail was a trifling little brick den that stood in a marsh at the edge -of the village, and no guards were afforded for it; indeed, it was -seldom occupied. These offerings greatly helped to ease Tom's -conscience. - -The villagers had a strong desire to tar-and-feather Injun Joe and -ride him on a rail, for body-snatching, but so formidable was his -character that nobody could be found who was willing to take the lead -in the matter, so it was dropped. He had been careful to begin both of -his inquest-statements with the fight, without confessing the -grave-robbery that preceded it; therefore it was deemed wisest not -to try the case in the courts at present. - - - -CHAPTER XII - -ONE of the reasons why Tom's mind had drifted away from its secret -troubles was, that it had found a new and weighty matter to interest -itself about. Becky Thatcher had stopped coming to school. Tom had -struggled with his pride a few days, and tried to "whistle her down the -wind," but failed. He began to find himself hanging around her father's -house, nights, and feeling very miserable. She was ill. What if she -should die! There was distraction in the thought. He no longer took an -interest in war, nor even in piracy. The charm of life was gone; there -was nothing but dreariness left. He put his hoop away, and his bat; -there was no joy in them any more. His aunt was concerned. She began to -try all manner of remedies on him. She was one of those people who are -infatuated with patent medicines and all new-fangled methods of -producing health or mending it. She was an inveterate experimenter in -these things. When something fresh in this line came out she was in a -fever, right away, to try it; not on herself, for she was never ailing, -but on anybody else that came handy. She was a subscriber for all the -"Health" periodicals and phrenological frauds; and the solemn ignorance -they were inflated with was breath to her nostrils. All the "rot" they -contained about ventilation, and how to go to bed, and how to get up, -and what to eat, and what to drink, and how much exercise to take, and -what frame of mind to keep one's self in, and what sort of clothing to -wear, was all gospel to her, and she never observed that her -health-journals of the current month customarily upset everything they -had recommended the month before. She was as simple-hearted and honest -as the day was long, and so she was an easy victim. She gathered -together her quack periodicals and her quack medicines, and thus armed -with death, went about on her pale horse, metaphorically speaking, with -"hell following after." But she never suspected that she was not an -angel of healing and the balm of Gilead in disguise, to the suffering -neighbors. - -The water treatment was new, now, and Tom's low condition was a -windfall to her. She had him out at daylight every morning, stood him -up in the woodshed and drowned him with a deluge of cold water; then -she scrubbed him down with a towel like a file, and so brought him to; -then she rolled him up in a wet sheet and put him away under blankets -till she sweated his soul clean and "the yellow stains of it came -through his pores"--as Tom said. - -Yet notwithstanding all this, the boy grew more and more melancholy -and pale and dejected. She added hot baths, sitz baths, shower baths, -and plunges. The boy remained as dismal as a hearse. She began to -assist the water with a slim oatmeal diet and blister-plasters. She -calculated his capacity as she would a jug's, and filled him up every -day with quack cure-alls. - -Tom had become indifferent to persecution by this time. This phase -filled the old lady's heart with consternation. This indifference must -be broken up at any cost. Now she heard of Pain-killer for the first -time. She ordered a lot at once. She tasted it and was filled with -gratitude. It was simply fire in a liquid form. She dropped the water -treatment and everything else, and pinned her faith to Pain-killer. She -gave Tom a teaspoonful and watched with the deepest anxiety for the -result. Her troubles were instantly at rest, her soul at peace again; -for the "indifference" was broken up. The boy could not have shown a -wilder, heartier interest, if she had built a fire under him. - -Tom felt that it was time to wake up; this sort of life might be -romantic enough, in his blighted condition, but it was getting to have -too little sentiment and too much distracting variety about it. So he -thought over various plans for relief, and finally hit pon that of -professing to be fond of Pain-killer. He asked for it so often that he -became a nuisance, and his aunt ended by telling him to help himself -and quit bothering her. If it had been Sid, she would have had no -misgivings to alloy her delight; but since it was Tom, she watched the -bottle clandestinely. She found that the medicine did really diminish, -but it did not occur to her that the boy was mending the health of a -crack in the sitting-room floor with it. - -One day Tom was in the act of dosing the crack when his aunt's yellow -cat came along, purring, eying the teaspoon avariciously, and begging -for a taste. Tom said: - -"Don't ask for it unless you want it, Peter." - -But Peter signified that he did want it. - -"You better make sure." - -Peter was sure. - -"Now you've asked for it, and I'll give it to you, because there ain't -anything mean about me; but if you find you don't like it, you mustn't -blame anybody but your own self." - -Peter was agreeable. So Tom pried his mouth open and poured down the -Pain-killer. Peter sprang a couple of yards in the air, and then -delivered a war-whoop and set off round and round the room, banging -against furniture, upsetting flower-pots, and making general havoc. -Next he rose on his hind feet and pranced around, in a frenzy of -enjoyment, with his head over his shoulder and his voice proclaiming -his unappeasable happiness. Then he went tearing around the house again -spreading chaos and destruction in his path. Aunt Polly entered in time -to see him throw a few double summersets, deliver a final mighty -hurrah, and sail through the open window, carrying the rest of the -flower-pots with him. The old lady stood petrified with astonishment, -peering over her glasses; Tom lay on the floor expiring with laughter. - -"Tom, what on earth ails that cat?" - -"I don't know, aunt," gasped the boy. - -"Why, I never see anything like it. What did make him act so?" - -"Deed I don't know, Aunt Polly; cats always act so when they're having -a good time." - -"They do, do they?" There was something in the tone that made Tom -apprehensive. - -"Yes'm. That is, I believe they do." - -"You DO?" - -"Yes'm." - -The old lady was bending down, Tom watching, with interest emphasized -by anxiety. Too late he divined her "drift." The handle of the telltale -teaspoon was visible under the bed-valance. Aunt Polly took it, held it -up. Tom winced, and dropped his eyes. Aunt Polly raised him by the -usual handle--his ear--and cracked his head soundly with her thimble. - -"Now, sir, what did you want to treat that poor dumb beast so, for?" - -"I done it out of pity for him--because he hadn't any aunt." - -"Hadn't any aunt!--you numskull. What has that got to do with it?" - -"Heaps. Because if he'd had one she'd a burnt him out herself! She'd a -roasted his bowels out of him 'thout any more feeling than if he was a -human!" - -Aunt Polly felt a sudden pang of remorse. This was putting the thing -in a new light; what was cruelty to a cat MIGHT be cruelty to a boy, -too. She began to soften; she felt sorry. Her eyes watered a little, -and she put her hand on Tom's head and said gently: - -"I was meaning for the best, Tom. And, Tom, it DID do you good." - -Tom looked up in her face with just a perceptible twinkle peeping -through his gravity. - -"I know you was meaning for the best, aunty, and so was I with Peter. -It done HIM good, too. I never see him get around so since--" - -"Oh, go 'long with you, Tom, before you aggravate me again. And you -try and see if you can't be a good boy, for once, and you needn't take -any more medicine." - -Tom reached school ahead of time. It was noticed that this strange -thing had been occurring every day latterly. And now, as usual of late, -he hung about the gate of the schoolyard instead of playing with his -comrades. He was sick, he said, and he looked it. He tried to seem to -be looking everywhere but whither he really was looking--down the road. -Presently Jeff Thatcher hove in sight, and Tom's face lighted; he gazed -a moment, and then turned sorrowfully away. When Jeff arrived, Tom -accosted him; and "led up" warily to opportunities for remark about -Becky, but the giddy lad never could see the bait. Tom watched and -watched, hoping whenever a frisking frock came in sight, and hating the -owner of it as soon as he saw she was not the right one. At last frocks -ceased to appear, and he dropped hopelessly into the dumps; he entered -the empty schoolhouse and sat down to suffer. Then one more frock -passed in at the gate, and Tom's heart gave a great bound. The next -instant he was out, and "going on" like an Indian; yelling, laughing, -chasing boys, jumping over the fence at risk of life and limb, throwing -handsprings, standing on his head--doing all the heroic things he could -conceive of, and keeping a furtive eye out, all the while, to see if -Becky Thatcher was noticing. But she seemed to be unconscious of it -all; she never looked. Could it be possible that she was not aware that -he was there? He carried his exploits to her immediate vicinity; came -war-whooping around, snatched a boy's cap, hurled it to the roof of the -schoolhouse, broke through a group of boys, tumbling them in every -direction, and fell sprawling, himself, under Becky's nose, almost -upsetting her--and she turned, with her nose in the air, and he heard -her say: "Mf! some people think they're mighty smart--always showing -off!" - -Tom's cheeks burned. He gathered himself up and sneaked off, crushed -and crestfallen. - - - -CHAPTER XIII - -TOM'S mind was made up now. He was gloomy and desperate. He was a -forsaken, friendless boy, he said; nobody loved him; when they found -out what they had driven him to, perhaps they would be sorry; he had -tried to do right and get along, but they would not let him; since -nothing would do them but to be rid of him, let it be so; and let them -blame HIM for the consequences--why shouldn't they? What right had the -friendless to complain? Yes, they had forced him to it at last: he -would lead a life of crime. There was no choice. - -By this time he was far down Meadow Lane, and the bell for school to -"take up" tinkled faintly upon his ear. He sobbed, now, to think he -should never, never hear that old familiar sound any more--it was very -hard, but it was forced on him; since he was driven out into the cold -world, he must submit--but he forgave them. Then the sobs came thick -and fast. - -Just at this point he met his soul's sworn comrade, Joe Harper ---hard-eyed, and with evidently a great and dismal purpose in his heart. -Plainly here were "two souls with but a single thought." Tom, wiping -his eyes with his sleeve, began to blubber out something about a -resolution to escape from hard usage and lack of sympathy at home by -roaming abroad into the great world never to return; and ended by -hoping that Joe would not forget him. - -But it transpired that this was a request which Joe had just been -going to make of Tom, and had come to hunt him up for that purpose. His -mother had whipped him for drinking some cream which he had never -tasted and knew nothing about; it was plain that she was tired of him -and wished him to go; if she felt that way, there was nothing for him -to do but succumb; he hoped she would be happy, and never regret having -driven her poor boy out into the unfeeling world to suffer and die. - -As the two boys walked sorrowing along, they made a new compact to -stand by each other and be brothers and never separate till death -relieved them of their troubles. Then they began to lay their plans. -Joe was for being a hermit, and living on crusts in a remote cave, and -dying, some time, of cold and want and grief; but after listening to -Tom, he conceded that there were some conspicuous advantages about a -life of crime, and so he consented to be a pirate. - -Three miles below St. Petersburg, at a point where the Mississippi -River was a trifle over a mile wide, there was a long, narrow, wooded -island, with a shallow bar at the head of it, and this offered well as -a rendezvous. It was not inhabited; it lay far over toward the further -shore, abreast a dense and almost wholly unpeopled forest. So Jackson's -Island was chosen. Who were to be the subjects of their piracies was a -matter that did not occur to them. Then they hunted up Huckleberry -Finn, and he joined them promptly, for all careers were one to him; he -was indifferent. They presently separated to meet at a lonely spot on -the river-bank two miles above the village at the favorite hour--which -was midnight. There was a small log raft there which they meant to -capture. Each would bring hooks and lines, and such provision as he -could steal in the most dark and mysterious way--as became outlaws. And -before the afternoon was done, they had all managed to enjoy the sweet -glory of spreading the fact that pretty soon the town would "hear -something." All who got this vague hint were cautioned to "be mum and -wait." - -About midnight Tom arrived with a boiled ham and a few trifles, -and stopped in a dense undergrowth on a small bluff overlooking the -meeting-place. It was starlight, and very still. The mighty river lay -like an ocean at rest. Tom listened a moment, but no sound disturbed the -quiet. Then he gave a low, distinct whistle. It was answered from under -the bluff. Tom whistled twice more; these signals were answered in the -same way. Then a guarded voice said: - -"Who goes there?" - -"Tom Sawyer, the Black Avenger of the Spanish Main. Name your names." - -"Huck Finn the Red-Handed, and Joe Harper the Terror of the Seas." Tom -had furnished these titles, from his favorite literature. - -"'Tis well. Give the countersign." - -Two hoarse whispers delivered the same awful word simultaneously to -the brooding night: - -"BLOOD!" - -Then Tom tumbled his ham over the bluff and let himself down after it, -tearing both skin and clothes to some extent in the effort. There was -an easy, comfortable path along the shore under the bluff, but it -lacked the advantages of difficulty and danger so valued by a pirate. - -The Terror of the Seas had brought a side of bacon, and had about worn -himself out with getting it there. Finn the Red-Handed had stolen a -skillet and a quantity of half-cured leaf tobacco, and had also brought -a few corn-cobs to make pipes with. But none of the pirates smoked or -"chewed" but himself. The Black Avenger of the Spanish Main said it -would never do to start without some fire. That was a wise thought; -matches were hardly known there in that day. They saw a fire -smouldering upon a great raft a hundred yards above, and they went -stealthily thither and helped themselves to a chunk. They made an -imposing adventure of it, saying, "Hist!" every now and then, and -suddenly halting with finger on lip; moving with hands on imaginary -dagger-hilts; and giving orders in dismal whispers that if "the foe" -stirred, to "let him have it to the hilt," because "dead men tell no -tales." They knew well enough that the raftsmen were all down at the -village laying in stores or having a spree, but still that was no -excuse for their conducting this thing in an unpiratical way. - -They shoved off, presently, Tom in command, Huck at the after oar and -Joe at the forward. Tom stood amidships, gloomy-browed, and with folded -arms, and gave his orders in a low, stern whisper: - -"Luff, and bring her to the wind!" - -"Aye-aye, sir!" - -"Steady, steady-y-y-y!" - -"Steady it is, sir!" - -"Let her go off a point!" - -"Point it is, sir!" - -As the boys steadily and monotonously drove the raft toward mid-stream -it was no doubt understood that these orders were given only for -"style," and were not intended to mean anything in particular. - -"What sail's she carrying?" - -"Courses, tops'ls, and flying-jib, sir." - -"Send the r'yals up! Lay out aloft, there, half a dozen of ye ---foretopmaststuns'l! Lively, now!" - -"Aye-aye, sir!" - -"Shake out that maintogalans'l! Sheets and braces! NOW my hearties!" - -"Aye-aye, sir!" - -"Hellum-a-lee--hard a port! Stand by to meet her when she comes! Port, -port! NOW, men! With a will! Stead-y-y-y!" - -"Steady it is, sir!" - -The raft drew beyond the middle of the river; the boys pointed her -head right, and then lay on their oars. The river was not high, so -there was not more than a two or three mile current. Hardly a word was -said during the next three-quarters of an hour. Now the raft was -passing before the distant town. Two or three glimmering lights showed -where it lay, peacefully sleeping, beyond the vague vast sweep of -star-gemmed water, unconscious of the tremendous event that was happening. -The Black Avenger stood still with folded arms, "looking his last" upon -the scene of his former joys and his later sufferings, and wishing -"she" could see him now, abroad on the wild sea, facing peril and death -with dauntless heart, going to his doom with a grim smile on his lips. -It was but a small strain on his imagination to remove Jackson's Island -beyond eyeshot of the village, and so he "looked his last" with a -broken and satisfied heart. The other pirates were looking their last, -too; and they all looked so long that they came near letting the -current drift them out of the range of the island. But they discovered -the danger in time, and made shift to avert it. About two o'clock in -the morning the raft grounded on the bar two hundred yards above the -head of the island, and they waded back and forth until they had landed -their freight. Part of the little raft's belongings consisted of an old -sail, and this they spread over a nook in the bushes for a tent to -shelter their provisions; but they themselves would sleep in the open -air in good weather, as became outlaws. - -They built a fire against the side of a great log twenty or thirty -steps within the sombre depths of the forest, and then cooked some -bacon in the frying-pan for supper, and used up half of the corn "pone" -stock they had brought. It seemed glorious sport to be feasting in that -wild, free way in the virgin forest of an unexplored and uninhabited -island, far from the haunts of men, and they said they never would -return to civilization. The climbing fire lit up their faces and threw -its ruddy glare upon the pillared tree-trunks of their forest temple, -and upon the varnished foliage and festooning vines. - -When the last crisp slice of bacon was gone, and the last allowance of -corn pone devoured, the boys stretched themselves out on the grass, -filled with contentment. They could have found a cooler place, but they -would not deny themselves such a romantic feature as the roasting -camp-fire. - -"AIN'T it gay?" said Joe. - -"It's NUTS!" said Tom. "What would the boys say if they could see us?" - -"Say? Well, they'd just die to be here--hey, Hucky!" - -"I reckon so," said Huckleberry; "anyways, I'm suited. I don't want -nothing better'n this. I don't ever get enough to eat, gen'ally--and -here they can't come and pick at a feller and bullyrag him so." - -"It's just the life for me," said Tom. "You don't have to get up, -mornings, and you don't have to go to school, and wash, and all that -blame foolishness. You see a pirate don't have to do ANYTHING, Joe, -when he's ashore, but a hermit HE has to be praying considerable, and -then he don't have any fun, anyway, all by himself that way." - -"Oh yes, that's so," said Joe, "but I hadn't thought much about it, -you know. I'd a good deal rather be a pirate, now that I've tried it." - -"You see," said Tom, "people don't go much on hermits, nowadays, like -they used to in old times, but a pirate's always respected. And a -hermit's got to sleep on the hardest place he can find, and put -sackcloth and ashes on his head, and stand out in the rain, and--" - -"What does he put sackcloth and ashes on his head for?" inquired Huck. - -"I dono. But they've GOT to do it. Hermits always do. You'd have to do -that if you was a hermit." - -"Dern'd if I would," said Huck. - -"Well, what would you do?" - -"I dono. But I wouldn't do that." - -"Why, Huck, you'd HAVE to. How'd you get around it?" - -"Why, I just wouldn't stand it. I'd run away." - -"Run away! Well, you WOULD be a nice old slouch of a hermit. You'd be -a disgrace." - -The Red-Handed made no response, being better employed. He had -finished gouging out a cob, and now he fitted a weed stem to it, loaded -it with tobacco, and was pressing a coal to the charge and blowing a -cloud of fragrant smoke--he was in the full bloom of luxurious -contentment. The other pirates envied him this majestic vice, and -secretly resolved to acquire it shortly. Presently Huck said: - -"What does pirates have to do?" - -Tom said: - -"Oh, they have just a bully time--take ships and burn them, and get -the money and bury it in awful places in their island where there's -ghosts and things to watch it, and kill everybody in the ships--make -'em walk a plank." - -"And they carry the women to the island," said Joe; "they don't kill -the women." - -"No," assented Tom, "they don't kill the women--they're too noble. And -the women's always beautiful, too. - -"And don't they wear the bulliest clothes! Oh no! All gold and silver -and di'monds," said Joe, with enthusiasm. - -"Who?" said Huck. - -"Why, the pirates." - -Huck scanned his own clothing forlornly. - -"I reckon I ain't dressed fitten for a pirate," said he, with a -regretful pathos in his voice; "but I ain't got none but these." - -But the other boys told him the fine clothes would come fast enough, -after they should have begun their adventures. They made him understand -that his poor rags would do to begin with, though it was customary for -wealthy pirates to start with a proper wardrobe. - -Gradually their talk died out and drowsiness began to steal upon the -eyelids of the little waifs. The pipe dropped from the fingers of the -Red-Handed, and he slept the sleep of the conscience-free and the -weary. The Terror of the Seas and the Black Avenger of the Spanish Main -had more difficulty in getting to sleep. They said their prayers -inwardly, and lying down, since there was nobody there with authority -to make them kneel and recite aloud; in truth, they had a mind not to -say them at all, but they were afraid to proceed to such lengths as -that, lest they might call down a sudden and special thunderbolt from -heaven. Then at once they reached and hovered upon the imminent verge -of sleep--but an intruder came, now, that would not "down." It was -conscience. They began to feel a vague fear that they had been doing -wrong to run away; and next they thought of the stolen meat, and then -the real torture came. They tried to argue it away by reminding -conscience that they had purloined sweetmeats and apples scores of -times; but conscience was not to be appeased by such thin -plausibilities; it seemed to them, in the end, that there was no -getting around the stubborn fact that taking sweetmeats was only -"hooking," while taking bacon and hams and such valuables was plain -simple stealing--and there was a command against that in the Bible. So -they inwardly resolved that so long as they remained in the business, -their piracies should not again be sullied with the crime of stealing. -Then conscience granted a truce, and these curiously inconsistent -pirates fell peacefully to sleep. - - - -CHAPTER XIV - -WHEN Tom awoke in the morning, he wondered where he was. He sat up and -rubbed his eyes and looked around. Then he comprehended. It was the -cool gray dawn, and there was a delicious sense of repose and peace in -the deep pervading calm and silence of the woods. Not a leaf stirred; -not a sound obtruded upon great Nature's meditation. Beaded dewdrops -stood upon the leaves and grasses. A white layer of ashes covered the -fire, and a thin blue breath of smoke rose straight into the air. Joe -and Huck still slept. - -Now, far away in the woods a bird called; another answered; presently -the hammering of a woodpecker was heard. Gradually the cool dim gray of -the morning whitened, and as gradually sounds multiplied and life -manifested itself. The marvel of Nature shaking off sleep and going to -work unfolded itself to the musing boy. A little green worm came -crawling over a dewy leaf, lifting two-thirds of his body into the air -from time to time and "sniffing around," then proceeding again--for he -was measuring, Tom said; and when the worm approached him, of its own -accord, he sat as still as a stone, with his hopes rising and falling, -by turns, as the creature still came toward him or seemed inclined to -go elsewhere; and when at last it considered a painful moment with its -curved body in the air and then came decisively down upon Tom's leg and -began a journey over him, his whole heart was glad--for that meant that -he was going to have a new suit of clothes--without the shadow of a -doubt a gaudy piratical uniform. Now a procession of ants appeared, -from nowhere in particular, and went about their labors; one struggled -manfully by with a dead spider five times as big as itself in its arms, -and lugged it straight up a tree-trunk. A brown spotted lady-bug -climbed the dizzy height of a grass blade, and Tom bent down close to -it and said, "Lady-bug, lady-bug, fly away home, your house is on fire, -your children's alone," and she took wing and went off to see about it ---which did not surprise the boy, for he knew of old that this insect was -credulous about conflagrations, and he had practised upon its -simplicity more than once. A tumblebug came next, heaving sturdily at -its ball, and Tom touched the creature, to see it shut its legs against -its body and pretend to be dead. The birds were fairly rioting by this -time. A catbird, the Northern mocker, lit in a tree over Tom's head, -and trilled out her imitations of her neighbors in a rapture of -enjoyment; then a shrill jay swept down, a flash of blue flame, and -stopped on a twig almost within the boy's reach, cocked his head to one -side and eyed the strangers with a consuming curiosity; a gray squirrel -and a big fellow of the "fox" kind came skurrying along, sitting up at -intervals to inspect and chatter at the boys, for the wild things had -probably never seen a human being before and scarcely knew whether to -be afraid or not. All Nature was wide awake and stirring, now; long -lances of sunlight pierced down through the dense foliage far and near, -and a few butterflies came fluttering upon the scene. - -Tom stirred up the other pirates and they all clattered away with a -shout, and in a minute or two were stripped and chasing after and -tumbling over each other in the shallow limpid water of the white -sandbar. They felt no longing for the little village sleeping in the -distance beyond the majestic waste of water. A vagrant current or a -slight rise in the river had carried off their raft, but this only -gratified them, since its going was something like burning the bridge -between them and civilization. - -They came back to camp wonderfully refreshed, glad-hearted, and -ravenous; and they soon had the camp-fire blazing up again. Huck found -a spring of clear cold water close by, and the boys made cups of broad -oak or hickory leaves, and felt that water, sweetened with such a -wildwood charm as that, would be a good enough substitute for coffee. -While Joe was slicing bacon for breakfast, Tom and Huck asked him to -hold on a minute; they stepped to a promising nook in the river-bank -and threw in their lines; almost immediately they had reward. Joe had -not had time to get impatient before they were back again with some -handsome bass, a couple of sun-perch and a small catfish--provisions -enough for quite a family. They fried the fish with the bacon, and were -astonished; for no fish had ever seemed so delicious before. They did -not know that the quicker a fresh-water fish is on the fire after he is -caught the better he is; and they reflected little upon what a sauce -open-air sleeping, open-air exercise, bathing, and a large ingredient -of hunger make, too. - -They lay around in the shade, after breakfast, while Huck had a smoke, -and then went off through the woods on an exploring expedition. They -tramped gayly along, over decaying logs, through tangled underbrush, -among solemn monarchs of the forest, hung from their crowns to the -ground with a drooping regalia of grape-vines. Now and then they came -upon snug nooks carpeted with grass and jeweled with flowers. - -They found plenty of things to be delighted with, but nothing to be -astonished at. They discovered that the island was about three miles -long and a quarter of a mile wide, and that the shore it lay closest to -was only separated from it by a narrow channel hardly two hundred yards -wide. They took a swim about every hour, so it was close upon the -middle of the afternoon when they got back to camp. They were too -hungry to stop to fish, but they fared sumptuously upon cold ham, and -then threw themselves down in the shade to talk. But the talk soon -began to drag, and then died. The stillness, the solemnity that brooded -in the woods, and the sense of loneliness, began to tell upon the -spirits of the boys. They fell to thinking. A sort of undefined longing -crept upon them. This took dim shape, presently--it was budding -homesickness. Even Finn the Red-Handed was dreaming of his doorsteps -and empty hogsheads. But they were all ashamed of their weakness, and -none was brave enough to speak his thought. - -For some time, now, the boys had been dully conscious of a peculiar -sound in the distance, just as one sometimes is of the ticking of a -clock which he takes no distinct note of. But now this mysterious sound -became more pronounced, and forced a recognition. The boys started, -glanced at each other, and then each assumed a listening attitude. -There was a long silence, profound and unbroken; then a deep, sullen -boom came floating down out of the distance. - -"What is it!" exclaimed Joe, under his breath. - -"I wonder," said Tom in a whisper. - -"'Tain't thunder," said Huckleberry, in an awed tone, "becuz thunder--" - -"Hark!" said Tom. "Listen--don't talk." - -They waited a time that seemed an age, and then the same muffled boom -troubled the solemn hush. - -"Let's go and see." - -They sprang to their feet and hurried to the shore toward the town. -They parted the bushes on the bank and peered out over the water. The -little steam ferryboat was about a mile below the village, drifting -with the current. Her broad deck seemed crowded with people. There were -a great many skiffs rowing about or floating with the stream in the -neighborhood of the ferryboat, but the boys could not determine what -the men in them were doing. Presently a great jet of white smoke burst -from the ferryboat's side, and as it expanded and rose in a lazy cloud, -that same dull throb of sound was borne to the listeners again. - -"I know now!" exclaimed Tom; "somebody's drownded!" - -"That's it!" said Huck; "they done that last summer, when Bill Turner -got drownded; they shoot a cannon over the water, and that makes him -come up to the top. Yes, and they take loaves of bread and put -quicksilver in 'em and set 'em afloat, and wherever there's anybody -that's drownded, they'll float right there and stop." - -"Yes, I've heard about that," said Joe. "I wonder what makes the bread -do that." - -"Oh, it ain't the bread, so much," said Tom; "I reckon it's mostly -what they SAY over it before they start it out." - -"But they don't say anything over it," said Huck. "I've seen 'em and -they don't." - -"Well, that's funny," said Tom. "But maybe they say it to themselves. -Of COURSE they do. Anybody might know that." - -The other boys agreed that there was reason in what Tom said, because -an ignorant lump of bread, uninstructed by an incantation, could not be -expected to act very intelligently when set upon an errand of such -gravity. - -"By jings, I wish I was over there, now," said Joe. - -"I do too" said Huck "I'd give heaps to know who it is." - -The boys still listened and watched. Presently a revealing thought -flashed through Tom's mind, and he exclaimed: - -"Boys, I know who's drownded--it's us!" - -They felt like heroes in an instant. Here was a gorgeous triumph; they -were missed; they were mourned; hearts were breaking on their account; -tears were being shed; accusing memories of unkindness to these poor -lost lads were rising up, and unavailing regrets and remorse were being -indulged; and best of all, the departed were the talk of the whole -town, and the envy of all the boys, as far as this dazzling notoriety -was concerned. This was fine. It was worth while to be a pirate, after -all. - -As twilight drew on, the ferryboat went back to her accustomed -business and the skiffs disappeared. The pirates returned to camp. They -were jubilant with vanity over their new grandeur and the illustrious -trouble they were making. They caught fish, cooked supper and ate it, -and then fell to guessing at what the village was thinking and saying -about them; and the pictures they drew of the public distress on their -account were gratifying to look upon--from their point of view. But -when the shadows of night closed them in, they gradually ceased to -talk, and sat gazing into the fire, with their minds evidently -wandering elsewhere. The excitement was gone, now, and Tom and Joe -could not keep back thoughts of certain persons at home who were not -enjoying this fine frolic as much as they were. Misgivings came; they -grew troubled and unhappy; a sigh or two escaped, unawares. By and by -Joe timidly ventured upon a roundabout "feeler" as to how the others -might look upon a return to civilization--not right now, but-- - -Tom withered him with derision! Huck, being uncommitted as yet, joined -in with Tom, and the waverer quickly "explained," and was glad to get -out of the scrape with as little taint of chicken-hearted homesickness -clinging to his garments as he could. Mutiny was effectually laid to -rest for the moment. - -As the night deepened, Huck began to nod, and presently to snore. Joe -followed next. Tom lay upon his elbow motionless, for some time, -watching the two intently. At last he got up cautiously, on his knees, -and went searching among the grass and the flickering reflections flung -by the camp-fire. He picked up and inspected several large -semi-cylinders of the thin white bark of a sycamore, and finally chose -two which seemed to suit him. Then he knelt by the fire and painfully -wrote something upon each of these with his "red keel"; one he rolled up -and put in his jacket pocket, and the other he put in Joe's hat and -removed it to a little distance from the owner. And he also put into the -hat certain schoolboy treasures of almost inestimable value--among them -a lump of chalk, an India-rubber ball, three fishhooks, and one of that -kind of marbles known as a "sure 'nough crystal." Then he tiptoed his -way cautiously among the trees till he felt that he was out of hearing, -and straightway broke into a keen run in the direction of the sandbar. - - - -CHAPTER XV - -A FEW minutes later Tom was in the shoal water of the bar, wading -toward the Illinois shore. Before the depth reached his middle he was -half-way over; the current would permit no more wading, now, so he -struck out confidently to swim the remaining hundred yards. He swam -quartering upstream, but still was swept downward rather faster than he -had expected. However, he reached the shore finally, and drifted along -till he found a low place and drew himself out. He put his hand on his -jacket pocket, found his piece of bark safe, and then struck through -the woods, following the shore, with streaming garments. Shortly before -ten o'clock he came out into an open place opposite the village, and -saw the ferryboat lying in the shadow of the trees and the high bank. -Everything was quiet under the blinking stars. He crept down the bank, -watching with all his eyes, slipped into the water, swam three or four -strokes and climbed into the skiff that did "yawl" duty at the boat's -stern. He laid himself down under the thwarts and waited, panting. - -Presently the cracked bell tapped and a voice gave the order to "cast -off." A minute or two later the skiff's head was standing high up, -against the boat's swell, and the voyage was begun. Tom felt happy in -his success, for he knew it was the boat's last trip for the night. At -the end of a long twelve or fifteen minutes the wheels stopped, and Tom -slipped overboard and swam ashore in the dusk, landing fifty yards -downstream, out of danger of possible stragglers. - -He flew along unfrequented alleys, and shortly found himself at his -aunt's back fence. He climbed over, approached the "ell," and looked in -at the sitting-room window, for a light was burning there. There sat -Aunt Polly, Sid, Mary, and Joe Harper's mother, grouped together, -talking. They were by the bed, and the bed was between them and the -door. Tom went to the door and began to softly lift the latch; then he -pressed gently and the door yielded a crack; he continued pushing -cautiously, and quaking every time it creaked, till he judged he might -squeeze through on his knees; so he put his head through and began, -warily. - -"What makes the candle blow so?" said Aunt Polly. Tom hurried up. -"Why, that door's open, I believe. Why, of course it is. No end of -strange things now. Go 'long and shut it, Sid." - -Tom disappeared under the bed just in time. He lay and "breathed" -himself for a time, and then crept to where he could almost touch his -aunt's foot. - -"But as I was saying," said Aunt Polly, "he warn't BAD, so to say ---only mischEEvous. Only just giddy, and harum-scarum, you know. He -warn't any more responsible than a colt. HE never meant any harm, and -he was the best-hearted boy that ever was"--and she began to cry. - -"It was just so with my Joe--always full of his devilment, and up to -every kind of mischief, but he was just as unselfish and kind as he -could be--and laws bless me, to think I went and whipped him for taking -that cream, never once recollecting that I throwed it out myself -because it was sour, and I never to see him again in this world, never, -never, never, poor abused boy!" And Mrs. Harper sobbed as if her heart -would break. - -"I hope Tom's better off where he is," said Sid, "but if he'd been -better in some ways--" - -"SID!" Tom felt the glare of the old lady's eye, though he could not -see it. "Not a word against my Tom, now that he's gone! God'll take -care of HIM--never you trouble YOURself, sir! Oh, Mrs. Harper, I don't -know how to give him up! I don't know how to give him up! He was such a -comfort to me, although he tormented my old heart out of me, 'most." - -"The Lord giveth and the Lord hath taken away--Blessed be the name of -the Lord! But it's so hard--Oh, it's so hard! Only last Saturday my -Joe busted a firecracker right under my nose and I knocked him -sprawling. Little did I know then, how soon--Oh, if it was to do over -again I'd hug him and bless him for it." - -"Yes, yes, yes, I know just how you feel, Mrs. Harper, I know just -exactly how you feel. No longer ago than yesterday noon, my Tom took -and filled the cat full of Pain-killer, and I did think the cretur -would tear the house down. And God forgive me, I cracked Tom's head -with my thimble, poor boy, poor dead boy. But he's out of all his -troubles now. And the last words I ever heard him say was to reproach--" - -But this memory was too much for the old lady, and she broke entirely -down. Tom was snuffling, now, himself--and more in pity of himself than -anybody else. He could hear Mary crying, and putting in a kindly word -for him from time to time. He began to have a nobler opinion of himself -than ever before. Still, he was sufficiently touched by his aunt's -grief to long to rush out from under the bed and overwhelm her with -joy--and the theatrical gorgeousness of the thing appealed strongly to -his nature, too, but he resisted and lay still. - -He went on listening, and gathered by odds and ends that it was -conjectured at first that the boys had got drowned while taking a swim; -then the small raft had been missed; next, certain boys said the -missing lads had promised that the village should "hear something" -soon; the wise-heads had "put this and that together" and decided that -the lads had gone off on that raft and would turn up at the next town -below, presently; but toward noon the raft had been found, lodged -against the Missouri shore some five or six miles below the village ---and then hope perished; they must be drowned, else hunger would have -driven them home by nightfall if not sooner. It was believed that the -search for the bodies had been a fruitless effort merely because the -drowning must have occurred in mid-channel, since the boys, being good -swimmers, would otherwise have escaped to shore. This was Wednesday -night. If the bodies continued missing until Sunday, all hope would be -given over, and the funerals would be preached on that morning. Tom -shuddered. - -Mrs. Harper gave a sobbing good-night and turned to go. Then with a -mutual impulse the two bereaved women flung themselves into each -other's arms and had a good, consoling cry, and then parted. Aunt Polly -was tender far beyond her wont, in her good-night to Sid and Mary. Sid -snuffled a bit and Mary went off crying with all her heart. - -Aunt Polly knelt down and prayed for Tom so touchingly, so -appealingly, and with such measureless love in her words and her old -trembling voice, that he was weltering in tears again, long before she -was through. - -He had to keep still long after she went to bed, for she kept making -broken-hearted ejaculations from time to time, tossing unrestfully, and -turning over. But at last she was still, only moaning a little in her -sleep. Now the boy stole out, rose gradually by the bedside, shaded the -candle-light with his hand, and stood regarding her. His heart was full -of pity for her. He took out his sycamore scroll and placed it by the -candle. But something occurred to him, and he lingered considering. His -face lighted with a happy solution of his thought; he put the bark -hastily in his pocket. Then he bent over and kissed the faded lips, and -straightway made his stealthy exit, latching the door behind him. - -He threaded his way back to the ferry landing, found nobody at large -there, and walked boldly on board the boat, for he knew she was -tenantless except that there was a watchman, who always turned in and -slept like a graven image. He untied the skiff at the stern, slipped -into it, and was soon rowing cautiously upstream. When he had pulled a -mile above the village, he started quartering across and bent himself -stoutly to his work. He hit the landing on the other side neatly, for -this was a familiar bit of work to him. He was moved to capture the -skiff, arguing that it might be considered a ship and therefore -legitimate prey for a pirate, but he knew a thorough search would be -made for it and that might end in revelations. So he stepped ashore and -entered the woods. - -He sat down and took a long rest, torturing himself meanwhile to keep -awake, and then started warily down the home-stretch. The night was far -spent. It was broad daylight before he found himself fairly abreast the -island bar. He rested again until the sun was well up and gilding the -great river with its splendor, and then he plunged into the stream. A -little later he paused, dripping, upon the threshold of the camp, and -heard Joe say: - -"No, Tom's true-blue, Huck, and he'll come back. He won't desert. He -knows that would be a disgrace to a pirate, and Tom's too proud for -that sort of thing. He's up to something or other. Now I wonder what?" - -"Well, the things is ours, anyway, ain't they?" - -"Pretty near, but not yet, Huck. The writing says they are if he ain't -back here to breakfast." - -"Which he is!" exclaimed Tom, with fine dramatic effect, stepping -grandly into camp. - -A sumptuous breakfast of bacon and fish was shortly provided, and as -the boys set to work upon it, Tom recounted (and adorned) his -adventures. They were a vain and boastful company of heroes when the -tale was done. Then Tom hid himself away in a shady nook to sleep till -noon, and the other pirates got ready to fish and explore. - - - -CHAPTER XVI - -AFTER dinner all the gang turned out to hunt for turtle eggs on the -bar. They went about poking sticks into the sand, and when they found a -soft place they went down on their knees and dug with their hands. -Sometimes they would take fifty or sixty eggs out of one hole. They -were perfectly round white things a trifle smaller than an English -walnut. They had a famous fried-egg feast that night, and another on -Friday morning. - -After breakfast they went whooping and prancing out on the bar, and -chased each other round and round, shedding clothes as they went, until -they were naked, and then continued the frolic far away up the shoal -water of the bar, against the stiff current, which latter tripped their -legs from under them from time to time and greatly increased the fun. -And now and then they stooped in a group and splashed water in each -other's faces with their palms, gradually approaching each other, with -averted faces to avoid the strangling sprays, and finally gripping and -struggling till the best man ducked his neighbor, and then they all -went under in a tangle of white legs and arms and came up blowing, -sputtering, laughing, and gasping for breath at one and the same time. - -When they were well exhausted, they would run out and sprawl on the -dry, hot sand, and lie there and cover themselves up with it, and by -and by break for the water again and go through the original -performance once more. Finally it occurred to them that their naked -skin represented flesh-colored "tights" very fairly; so they drew a -ring in the sand and had a circus--with three clowns in it, for none -would yield this proudest post to his neighbor. - -Next they got their marbles and played "knucks" and "ring-taw" and -"keeps" till that amusement grew stale. Then Joe and Huck had another -swim, but Tom would not venture, because he found that in kicking off -his trousers he had kicked his string of rattlesnake rattles off his -ankle, and he wondered how he had escaped cramp so long without the -protection of this mysterious charm. He did not venture again until he -had found it, and by that time the other boys were tired and ready to -rest. They gradually wandered apart, dropped into the "dumps," and fell -to gazing longingly across the wide river to where the village lay -drowsing in the sun. Tom found himself writing "BECKY" in the sand with -his big toe; he scratched it out, and was angry with himself for his -weakness. But he wrote it again, nevertheless; he could not help it. He -erased it once more and then took himself out of temptation by driving -the other boys together and joining them. - -But Joe's spirits had gone down almost beyond resurrection. He was so -homesick that he could hardly endure the misery of it. The tears lay -very near the surface. Huck was melancholy, too. Tom was downhearted, -but tried hard not to show it. He had a secret which he was not ready -to tell, yet, but if this mutinous depression was not broken up soon, -he would have to bring it out. He said, with a great show of -cheerfulness: - -"I bet there's been pirates on this island before, boys. We'll explore -it again. They've hid treasures here somewhere. How'd you feel to light -on a rotten chest full of gold and silver--hey?" - -But it roused only faint enthusiasm, which faded out, with no reply. -Tom tried one or two other seductions; but they failed, too. It was -discouraging work. Joe sat poking up the sand with a stick and looking -very gloomy. Finally he said: - -"Oh, boys, let's give it up. I want to go home. It's so lonesome." - -"Oh no, Joe, you'll feel better by and by," said Tom. "Just think of -the fishing that's here." - -"I don't care for fishing. I want to go home." - -"But, Joe, there ain't such another swimming-place anywhere." - -"Swimming's no good. I don't seem to care for it, somehow, when there -ain't anybody to say I sha'n't go in. I mean to go home." - -"Oh, shucks! Baby! You want to see your mother, I reckon." - -"Yes, I DO want to see my mother--and you would, too, if you had one. -I ain't any more baby than you are." And Joe snuffled a little. - -"Well, we'll let the cry-baby go home to his mother, won't we, Huck? -Poor thing--does it want to see its mother? And so it shall. You like -it here, don't you, Huck? We'll stay, won't we?" - -Huck said, "Y-e-s"--without any heart in it. - -"I'll never speak to you again as long as I live," said Joe, rising. -"There now!" And he moved moodily away and began to dress himself. - -"Who cares!" said Tom. "Nobody wants you to. Go 'long home and get -laughed at. Oh, you're a nice pirate. Huck and me ain't cry-babies. -We'll stay, won't we, Huck? Let him go if he wants to. I reckon we can -get along without him, per'aps." - -But Tom was uneasy, nevertheless, and was alarmed to see Joe go -sullenly on with his dressing. And then it was discomforting to see -Huck eying Joe's preparations so wistfully, and keeping up such an -ominous silence. Presently, without a parting word, Joe began to wade -off toward the Illinois shore. Tom's heart began to sink. He glanced at -Huck. Huck could not bear the look, and dropped his eyes. Then he said: - -"I want to go, too, Tom. It was getting so lonesome anyway, and now -it'll be worse. Let's us go, too, Tom." - -"I won't! You can all go, if you want to. I mean to stay." - -"Tom, I better go." - -"Well, go 'long--who's hendering you." - -Huck began to pick up his scattered clothes. He said: - -"Tom, I wisht you'd come, too. Now you think it over. We'll wait for -you when we get to shore." - -"Well, you'll wait a blame long time, that's all." - -Huck started sorrowfully away, and Tom stood looking after him, with a -strong desire tugging at his heart to yield his pride and go along too. -He hoped the boys would stop, but they still waded slowly on. It -suddenly dawned on Tom that it was become very lonely and still. He -made one final struggle with his pride, and then darted after his -comrades, yelling: - -"Wait! Wait! I want to tell you something!" - -They presently stopped and turned around. When he got to where they -were, he began unfolding his secret, and they listened moodily till at -last they saw the "point" he was driving at, and then they set up a -war-whoop of applause and said it was "splendid!" and said if he had -told them at first, they wouldn't have started away. He made a plausible -excuse; but his real reason had been the fear that not even the secret -would keep them with him any very great length of time, and so he had -meant to hold it in reserve as a last seduction. - -The lads came gayly back and went at their sports again with a will, -chattering all the time about Tom's stupendous plan and admiring the -genius of it. After a dainty egg and fish dinner, Tom said he wanted to -learn to smoke, now. Joe caught at the idea and said he would like to -try, too. So Huck made pipes and filled them. These novices had never -smoked anything before but cigars made of grape-vine, and they "bit" -the tongue, and were not considered manly anyway. - -Now they stretched themselves out on their elbows and began to puff, -charily, and with slender confidence. The smoke had an unpleasant -taste, and they gagged a little, but Tom said: - -"Why, it's just as easy! If I'd a knowed this was all, I'd a learnt -long ago." - -"So would I," said Joe. "It's just nothing." - -"Why, many a time I've looked at people smoking, and thought well I -wish I could do that; but I never thought I could," said Tom. - -"That's just the way with me, hain't it, Huck? You've heard me talk -just that way--haven't you, Huck? I'll leave it to Huck if I haven't." - -"Yes--heaps of times," said Huck. - -"Well, I have too," said Tom; "oh, hundreds of times. Once down by the -slaughter-house. Don't you remember, Huck? Bob Tanner was there, and -Johnny Miller, and Jeff Thatcher, when I said it. Don't you remember, -Huck, 'bout me saying that?" - -"Yes, that's so," said Huck. "That was the day after I lost a white -alley. No, 'twas the day before." - -"There--I told you so," said Tom. "Huck recollects it." - -"I bleeve I could smoke this pipe all day," said Joe. "I don't feel -sick." - -"Neither do I," said Tom. "I could smoke it all day. But I bet you -Jeff Thatcher couldn't." - -"Jeff Thatcher! Why, he'd keel over just with two draws. Just let him -try it once. HE'D see!" - -"I bet he would. And Johnny Miller--I wish could see Johnny Miller -tackle it once." - -"Oh, don't I!" said Joe. "Why, I bet you Johnny Miller couldn't any -more do this than nothing. Just one little snifter would fetch HIM." - -"'Deed it would, Joe. Say--I wish the boys could see us now." - -"So do I." - -"Say--boys, don't say anything about it, and some time when they're -around, I'll come up to you and say, 'Joe, got a pipe? I want a smoke.' -And you'll say, kind of careless like, as if it warn't anything, you'll -say, 'Yes, I got my OLD pipe, and another one, but my tobacker ain't -very good.' And I'll say, 'Oh, that's all right, if it's STRONG -enough.' And then you'll out with the pipes, and we'll light up just as -ca'm, and then just see 'em look!" - -"By jings, that'll be gay, Tom! I wish it was NOW!" - -"So do I! And when we tell 'em we learned when we was off pirating, -won't they wish they'd been along?" - -"Oh, I reckon not! I'll just BET they will!" - -So the talk ran on. But presently it began to flag a trifle, and grow -disjointed. The silences widened; the expectoration marvellously -increased. Every pore inside the boys' cheeks became a spouting -fountain; they could scarcely bail out the cellars under their tongues -fast enough to prevent an inundation; little overflowings down their -throats occurred in spite of all they could do, and sudden retchings -followed every time. Both boys were looking very pale and miserable, -now. Joe's pipe dropped from his nerveless fingers. Tom's followed. -Both fountains were going furiously and both pumps bailing with might -and main. Joe said feebly: - -"I've lost my knife. I reckon I better go and find it." - -Tom said, with quivering lips and halting utterance: - -"I'll help you. You go over that way and I'll hunt around by the -spring. No, you needn't come, Huck--we can find it." - -So Huck sat down again, and waited an hour. Then he found it lonesome, -and went to find his comrades. They were wide apart in the woods, both -very pale, both fast asleep. But something informed him that if they -had had any trouble they had got rid of it. - -They were not talkative at supper that night. They had a humble look, -and when Huck prepared his pipe after the meal and was going to prepare -theirs, they said no, they were not feeling very well--something they -ate at dinner had disagreed with them. - -About midnight Joe awoke, and called the boys. There was a brooding -oppressiveness in the air that seemed to bode something. The boys -huddled themselves together and sought the friendly companionship of -the fire, though the dull dead heat of the breathless atmosphere was -stifling. They sat still, intent and waiting. The solemn hush -continued. Beyond the light of the fire everything was swallowed up in -the blackness of darkness. Presently there came a quivering glow that -vaguely revealed the foliage for a moment and then vanished. By and by -another came, a little stronger. Then another. Then a faint moan came -sighing through the branches of the forest and the boys felt a fleeting -breath upon their cheeks, and shuddered with the fancy that the Spirit -of the Night had gone by. There was a pause. Now a weird flash turned -night into day and showed every little grass-blade, separate and -distinct, that grew about their feet. And it showed three white, -startled faces, too. A deep peal of thunder went rolling and tumbling -down the heavens and lost itself in sullen rumblings in the distance. A -sweep of chilly air passed by, rustling all the leaves and snowing the -flaky ashes broadcast about the fire. Another fierce glare lit up the -forest and an instant crash followed that seemed to rend the tree-tops -right over the boys' heads. They clung together in terror, in the thick -gloom that followed. A few big rain-drops fell pattering upon the -leaves. - -"Quick! boys, go for the tent!" exclaimed Tom. - -They sprang away, stumbling over roots and among vines in the dark, no -two plunging in the same direction. A furious blast roared through the -trees, making everything sing as it went. One blinding flash after -another came, and peal on peal of deafening thunder. And now a -drenching rain poured down and the rising hurricane drove it in sheets -along the ground. The boys cried out to each other, but the roaring -wind and the booming thunder-blasts drowned their voices utterly. -However, one by one they straggled in at last and took shelter under -the tent, cold, scared, and streaming with water; but to have company -in misery seemed something to be grateful for. They could not talk, the -old sail flapped so furiously, even if the other noises would have -allowed them. The tempest rose higher and higher, and presently the -sail tore loose from its fastenings and went winging away on the blast. -The boys seized each others' hands and fled, with many tumblings and -bruises, to the shelter of a great oak that stood upon the river-bank. -Now the battle was at its highest. Under the ceaseless conflagration of -lightning that flamed in the skies, everything below stood out in -clean-cut and shadowless distinctness: the bending trees, the billowy -river, white with foam, the driving spray of spume-flakes, the dim -outlines of the high bluffs on the other side, glimpsed through the -drifting cloud-rack and the slanting veil of rain. Every little while -some giant tree yielded the fight and fell crashing through the younger -growth; and the unflagging thunder-peals came now in ear-splitting -explosive bursts, keen and sharp, and unspeakably appalling. The storm -culminated in one matchless effort that seemed likely to tear the island -to pieces, burn it up, drown it to the tree-tops, blow it away, and -deafen every creature in it, all at one and the same moment. It was a -wild night for homeless young heads to be out in. - -But at last the battle was done, and the forces retired with weaker -and weaker threatenings and grumblings, and peace resumed her sway. The -boys went back to camp, a good deal awed; but they found there was -still something to be thankful for, because the great sycamore, the -shelter of their beds, was a ruin, now, blasted by the lightnings, and -they were not under it when the catastrophe happened. - -Everything in camp was drenched, the camp-fire as well; for they were -but heedless lads, like their generation, and had made no provision -against rain. Here was matter for dismay, for they were soaked through -and chilled. They were eloquent in their distress; but they presently -discovered that the fire had eaten so far up under the great log it had -been built against (where it curved upward and separated itself from -the ground), that a handbreadth or so of it had escaped wetting; so -they patiently wrought until, with shreds and bark gathered from the -under sides of sheltered logs, they coaxed the fire to burn again. Then -they piled on great dead boughs till they had a roaring furnace, and -were glad-hearted once more. They dried their boiled ham and had a -feast, and after that they sat by the fire and expanded and glorified -their midnight adventure until morning, for there was not a dry spot to -sleep on, anywhere around. - -As the sun began to steal in upon the boys, drowsiness came over them, -and they went out on the sandbar and lay down to sleep. They got -scorched out by and by, and drearily set about getting breakfast. After -the meal they felt rusty, and stiff-jointed, and a little homesick once -more. Tom saw the signs, and fell to cheering up the pirates as well as -he could. But they cared nothing for marbles, or circus, or swimming, -or anything. He reminded them of the imposing secret, and raised a ray -of cheer. While it lasted, he got them interested in a new device. This -was to knock off being pirates, for a while, and be Indians for a -change. They were attracted by this idea; so it was not long before -they were stripped, and striped from head to heel with black mud, like -so many zebras--all of them chiefs, of course--and then they went -tearing through the woods to attack an English settlement. - -By and by they separated into three hostile tribes, and darted upon -each other from ambush with dreadful war-whoops, and killed and scalped -each other by thousands. It was a gory day. Consequently it was an -extremely satisfactory one. - -They assembled in camp toward supper-time, hungry and happy; but now a -difficulty arose--hostile Indians could not break the bread of -hospitality together without first making peace, and this was a simple -impossibility without smoking a pipe of peace. There was no other -process that ever they had heard of. Two of the savages almost wished -they had remained pirates. However, there was no other way; so with -such show of cheerfulness as they could muster they called for the pipe -and took their whiff as it passed, in due form. - -And behold, they were glad they had gone into savagery, for they had -gained something; they found that they could now smoke a little without -having to go and hunt for a lost knife; they did not get sick enough to -be seriously uncomfortable. They were not likely to fool away this high -promise for lack of effort. No, they practised cautiously, after -supper, with right fair success, and so they spent a jubilant evening. -They were prouder and happier in their new acquirement than they would -have been in the scalping and skinning of the Six Nations. We will -leave them to smoke and chatter and brag, since we have no further use -for them at present. - - - -CHAPTER XVII - -BUT there was no hilarity in the little town that same tranquil -Saturday afternoon. The Harpers, and Aunt Polly's family, were being -put into mourning, with great grief and many tears. An unusual quiet -possessed the village, although it was ordinarily quiet enough, in all -conscience. The villagers conducted their concerns with an absent air, -and talked little; but they sighed often. The Saturday holiday seemed a -burden to the children. They had no heart in their sports, and -gradually gave them up. - -In the afternoon Becky Thatcher found herself moping about the -deserted schoolhouse yard, and feeling very melancholy. But she found -nothing there to comfort her. She soliloquized: - -"Oh, if I only had a brass andiron-knob again! But I haven't got -anything now to remember him by." And she choked back a little sob. - -Presently she stopped, and said to herself: - -"It was right here. Oh, if it was to do over again, I wouldn't say -that--I wouldn't say it for the whole world. But he's gone now; I'll -never, never, never see him any more." - -This thought broke her down, and she wandered away, with tears rolling -down her cheeks. Then quite a group of boys and girls--playmates of -Tom's and Joe's--came by, and stood looking over the paling fence and -talking in reverent tones of how Tom did so-and-so the last time they -saw him, and how Joe said this and that small trifle (pregnant with -awful prophecy, as they could easily see now!)--and each speaker -pointed out the exact spot where the lost lads stood at the time, and -then added something like "and I was a-standing just so--just as I am -now, and as if you was him--I was as close as that--and he smiled, just -this way--and then something seemed to go all over me, like--awful, you -know--and I never thought what it meant, of course, but I can see now!" - -Then there was a dispute about who saw the dead boys last in life, and -many claimed that dismal distinction, and offered evidences, more or -less tampered with by the witness; and when it was ultimately decided -who DID see the departed last, and exchanged the last words with them, -the lucky parties took upon themselves a sort of sacred importance, and -were gaped at and envied by all the rest. One poor chap, who had no -other grandeur to offer, said with tolerably manifest pride in the -remembrance: - -"Well, Tom Sawyer he licked me once." - -But that bid for glory was a failure. Most of the boys could say that, -and so that cheapened the distinction too much. The group loitered -away, still recalling memories of the lost heroes, in awed voices. - -When the Sunday-school hour was finished, the next morning, the bell -began to toll, instead of ringing in the usual way. It was a very still -Sabbath, and the mournful sound seemed in keeping with the musing hush -that lay upon nature. The villagers began to gather, loitering a moment -in the vestibule to converse in whispers about the sad event. But there -was no whispering in the house; only the funereal rustling of dresses -as the women gathered to their seats disturbed the silence there. None -could remember when the little church had been so full before. There -was finally a waiting pause, an expectant dumbness, and then Aunt Polly -entered, followed by Sid and Mary, and they by the Harper family, all -in deep black, and the whole congregation, the old minister as well, -rose reverently and stood until the mourners were seated in the front -pew. There was another communing silence, broken at intervals by -muffled sobs, and then the minister spread his hands abroad and prayed. -A moving hymn was sung, and the text followed: "I am the Resurrection -and the Life." - -As the service proceeded, the clergyman drew such pictures of the -graces, the winning ways, and the rare promise of the lost lads that -every soul there, thinking he recognized these pictures, felt a pang in -remembering that he had persistently blinded himself to them always -before, and had as persistently seen only faults and flaws in the poor -boys. The minister related many a touching incident in the lives of the -departed, too, which illustrated their sweet, generous natures, and the -people could easily see, now, how noble and beautiful those episodes -were, and remembered with grief that at the time they occurred they had -seemed rank rascalities, well deserving of the cowhide. The -congregation became more and more moved, as the pathetic tale went on, -till at last the whole company broke down and joined the weeping -mourners in a chorus of anguished sobs, the preacher himself giving way -to his feelings, and crying in the pulpit. - -There was a rustle in the gallery, which nobody noticed; a moment -later the church door creaked; the minister raised his streaming eyes -above his handkerchief, and stood transfixed! First one and then -another pair of eyes followed the minister's, and then almost with one -impulse the congregation rose and stared while the three dead boys came -marching up the aisle, Tom in the lead, Joe next, and Huck, a ruin of -drooping rags, sneaking sheepishly in the rear! They had been hid in -the unused gallery listening to their own funeral sermon! - -Aunt Polly, Mary, and the Harpers threw themselves upon their restored -ones, smothered them with kisses and poured out thanksgivings, while -poor Huck stood abashed and uncomfortable, not knowing exactly what to -do or where to hide from so many unwelcoming eyes. He wavered, and -started to slink away, but Tom seized him and said: - -"Aunt Polly, it ain't fair. Somebody's got to be glad to see Huck." - -"And so they shall. I'm glad to see him, poor motherless thing!" And -the loving attentions Aunt Polly lavished upon him were the one thing -capable of making him more uncomfortable than he was before. - -Suddenly the minister shouted at the top of his voice: "Praise God -from whom all blessings flow--SING!--and put your hearts in it!" - -And they did. Old Hundred swelled up with a triumphant burst, and -while it shook the rafters Tom Sawyer the Pirate looked around upon the -envying juveniles about him and confessed in his heart that this was -the proudest moment of his life. - -As the "sold" congregation trooped out they said they would almost be -willing to be made ridiculous again to hear Old Hundred sung like that -once more. - -Tom got more cuffs and kisses that day--according to Aunt Polly's -varying moods--than he had earned before in a year; and he hardly knew -which expressed the most gratefulness to God and affection for himself. - - - -CHAPTER XVIII - -THAT was Tom's great secret--the scheme to return home with his -brother pirates and attend their own funerals. They had paddled over to -the Missouri shore on a log, at dusk on Saturday, landing five or six -miles below the village; they had slept in the woods at the edge of the -town till nearly daylight, and had then crept through back lanes and -alleys and finished their sleep in the gallery of the church among a -chaos of invalided benches. - -At breakfast, Monday morning, Aunt Polly and Mary were very loving to -Tom, and very attentive to his wants. There was an unusual amount of -talk. In the course of it Aunt Polly said: - -"Well, I don't say it wasn't a fine joke, Tom, to keep everybody -suffering 'most a week so you boys had a good time, but it is a pity -you could be so hard-hearted as to let me suffer so. If you could come -over on a log to go to your funeral, you could have come over and give -me a hint some way that you warn't dead, but only run off." - -"Yes, you could have done that, Tom," said Mary; "and I believe you -would if you had thought of it." - -"Would you, Tom?" said Aunt Polly, her face lighting wistfully. "Say, -now, would you, if you'd thought of it?" - -"I--well, I don't know. 'Twould 'a' spoiled everything." - -"Tom, I hoped you loved me that much," said Aunt Polly, with a grieved -tone that discomforted the boy. "It would have been something if you'd -cared enough to THINK of it, even if you didn't DO it." - -"Now, auntie, that ain't any harm," pleaded Mary; "it's only Tom's -giddy way--he is always in such a rush that he never thinks of -anything." - -"More's the pity. Sid would have thought. And Sid would have come and -DONE it, too. Tom, you'll look back, some day, when it's too late, and -wish you'd cared a little more for me when it would have cost you so -little." - -"Now, auntie, you know I do care for you," said Tom. - -"I'd know it better if you acted more like it." - -"I wish now I'd thought," said Tom, with a repentant tone; "but I -dreamt about you, anyway. That's something, ain't it?" - -"It ain't much--a cat does that much--but it's better than nothing. -What did you dream?" - -"Why, Wednesday night I dreamt that you was sitting over there by the -bed, and Sid was sitting by the woodbox, and Mary next to him." - -"Well, so we did. So we always do. I'm glad your dreams could take -even that much trouble about us." - -"And I dreamt that Joe Harper's mother was here." - -"Why, she was here! Did you dream any more?" - -"Oh, lots. But it's so dim, now." - -"Well, try to recollect--can't you?" - -"Somehow it seems to me that the wind--the wind blowed the--the--" - -"Try harder, Tom! The wind did blow something. Come!" - -Tom pressed his fingers on his forehead an anxious minute, and then -said: - -"I've got it now! I've got it now! It blowed the candle!" - -"Mercy on us! Go on, Tom--go on!" - -"And it seems to me that you said, 'Why, I believe that that door--'" - -"Go ON, Tom!" - -"Just let me study a moment--just a moment. Oh, yes--you said you -believed the door was open." - -"As I'm sitting here, I did! Didn't I, Mary! Go on!" - -"And then--and then--well I won't be certain, but it seems like as if -you made Sid go and--and--" - -"Well? Well? What did I make him do, Tom? What did I make him do?" - -"You made him--you--Oh, you made him shut it." - -"Well, for the land's sake! I never heard the beat of that in all my -days! Don't tell ME there ain't anything in dreams, any more. Sereny -Harper shall know of this before I'm an hour older. I'd like to see her -get around THIS with her rubbage 'bout superstition. Go on, Tom!" - -"Oh, it's all getting just as bright as day, now. Next you said I -warn't BAD, only mischeevous and harum-scarum, and not any more -responsible than--than--I think it was a colt, or something." - -"And so it was! Well, goodness gracious! Go on, Tom!" - -"And then you began to cry." - -"So I did. So I did. Not the first time, neither. And then--" - -"Then Mrs. Harper she began to cry, and said Joe was just the same, -and she wished she hadn't whipped him for taking cream when she'd -throwed it out her own self--" - -"Tom! The sperrit was upon you! You was a prophesying--that's what you -was doing! Land alive, go on, Tom!" - -"Then Sid he said--he said--" - -"I don't think I said anything," said Sid. - -"Yes you did, Sid," said Mary. - -"Shut your heads and let Tom go on! What did he say, Tom?" - -"He said--I THINK he said he hoped I was better off where I was gone -to, but if I'd been better sometimes--" - -"THERE, d'you hear that! It was his very words!" - -"And you shut him up sharp." - -"I lay I did! There must 'a' been an angel there. There WAS an angel -there, somewheres!" - -"And Mrs. Harper told about Joe scaring her with a firecracker, and -you told about Peter and the Painkiller--" - -"Just as true as I live!" - -"And then there was a whole lot of talk 'bout dragging the river for -us, and 'bout having the funeral Sunday, and then you and old Miss -Harper hugged and cried, and she went." - -"It happened just so! It happened just so, as sure as I'm a-sitting in -these very tracks. Tom, you couldn't told it more like if you'd 'a' -seen it! And then what? Go on, Tom!" - -"Then I thought you prayed for me--and I could see you and hear every -word you said. And you went to bed, and I was so sorry that I took and -wrote on a piece of sycamore bark, 'We ain't dead--we are only off -being pirates,' and put it on the table by the candle; and then you -looked so good, laying there asleep, that I thought I went and leaned -over and kissed you on the lips." - -"Did you, Tom, DID you! I just forgive you everything for that!" And -she seized the boy in a crushing embrace that made him feel like the -guiltiest of villains. - -"It was very kind, even though it was only a--dream," Sid soliloquized -just audibly. - -"Shut up, Sid! A body does just the same in a dream as he'd do if he -was awake. Here's a big Milum apple I've been saving for you, Tom, if -you was ever found again--now go 'long to school. I'm thankful to the -good God and Father of us all I've got you back, that's long-suffering -and merciful to them that believe on Him and keep His word, though -goodness knows I'm unworthy of it, but if only the worthy ones got His -blessings and had His hand to help them over the rough places, there's -few enough would smile here or ever enter into His rest when the long -night comes. Go 'long Sid, Mary, Tom--take yourselves off--you've -hendered me long enough." - -The children left for school, and the old lady to call on Mrs. Harper -and vanquish her realism with Tom's marvellous dream. Sid had better -judgment than to utter the thought that was in his mind as he left the -house. It was this: "Pretty thin--as long a dream as that, without any -mistakes in it!" - -What a hero Tom was become, now! He did not go skipping and prancing, -but moved with a dignified swagger as became a pirate who felt that the -public eye was on him. And indeed it was; he tried not to seem to see -the looks or hear the remarks as he passed along, but they were food -and drink to him. Smaller boys than himself flocked at his heels, as -proud to be seen with him, and tolerated by him, as if he had been the -drummer at the head of a procession or the elephant leading a menagerie -into town. Boys of his own size pretended not to know he had been away -at all; but they were consuming with envy, nevertheless. They would -have given anything to have that swarthy suntanned skin of his, and his -glittering notoriety; and Tom would not have parted with either for a -circus. - -At school the children made so much of him and of Joe, and delivered -such eloquent admiration from their eyes, that the two heroes were not -long in becoming insufferably "stuck-up." They began to tell their -adventures to hungry listeners--but they only began; it was not a thing -likely to have an end, with imaginations like theirs to furnish -material. And finally, when they got out their pipes and went serenely -puffing around, the very summit of glory was reached. - -Tom decided that he could be independent of Becky Thatcher now. Glory -was sufficient. He would live for glory. Now that he was distinguished, -maybe she would be wanting to "make up." Well, let her--she should see -that he could be as indifferent as some other people. Presently she -arrived. Tom pretended not to see her. He moved away and joined a group -of boys and girls and began to talk. Soon he observed that she was -tripping gayly back and forth with flushed face and dancing eyes, -pretending to be busy chasing schoolmates, and screaming with laughter -when she made a capture; but he noticed that she always made her -captures in his vicinity, and that she seemed to cast a conscious eye -in his direction at such times, too. It gratified all the vicious -vanity that was in him; and so, instead of winning him, it only "set -him up" the more and made him the more diligent to avoid betraying that -he knew she was about. Presently she gave over skylarking, and moved -irresolutely about, sighing once or twice and glancing furtively and -wistfully toward Tom. Then she observed that now Tom was talking more -particularly to Amy Lawrence than to any one else. She felt a sharp -pang and grew disturbed and uneasy at once. She tried to go away, but -her feet were treacherous, and carried her to the group instead. She -said to a girl almost at Tom's elbow--with sham vivacity: - -"Why, Mary Austin! you bad girl, why didn't you come to Sunday-school?" - -"I did come--didn't you see me?" - -"Why, no! Did you? Where did you sit?" - -"I was in Miss Peters' class, where I always go. I saw YOU." - -"Did you? Why, it's funny I didn't see you. I wanted to tell you about -the picnic." - -"Oh, that's jolly. Who's going to give it?" - -"My ma's going to let me have one." - -"Oh, goody; I hope she'll let ME come." - -"Well, she will. The picnic's for me. She'll let anybody come that I -want, and I want you." - -"That's ever so nice. When is it going to be?" - -"By and by. Maybe about vacation." - -"Oh, won't it be fun! You going to have all the girls and boys?" - -"Yes, every one that's friends to me--or wants to be"; and she glanced -ever so furtively at Tom, but he talked right along to Amy Lawrence -about the terrible storm on the island, and how the lightning tore the -great sycamore tree "all to flinders" while he was "standing within -three feet of it." - -"Oh, may I come?" said Grace Miller. - -"Yes." - -"And me?" said Sally Rogers. - -"Yes." - -"And me, too?" said Susy Harper. "And Joe?" - -"Yes." - -And so on, with clapping of joyful hands till all the group had begged -for invitations but Tom and Amy. Then Tom turned coolly away, still -talking, and took Amy with him. Becky's lips trembled and the tears -came to her eyes; she hid these signs with a forced gayety and went on -chattering, but the life had gone out of the picnic, now, and out of -everything else; she got away as soon as she could and hid herself and -had what her sex call "a good cry." Then she sat moody, with wounded -pride, till the bell rang. She roused up, now, with a vindictive cast -in her eye, and gave her plaited tails a shake and said she knew what -SHE'D do. - -At recess Tom continued his flirtation with Amy with jubilant -self-satisfaction. And he kept drifting about to find Becky and lacerate -her with the performance. At last he spied her, but there was a sudden -falling of his mercury. She was sitting cosily on a little bench behind -the schoolhouse looking at a picture-book with Alfred Temple--and so -absorbed were they, and their heads so close together over the book, -that they did not seem to be conscious of anything in the world besides. -Jealousy ran red-hot through Tom's veins. He began to hate himself for -throwing away the chance Becky had offered for a reconciliation. He -called himself a fool, and all the hard names he could think of. He -wanted to cry with vexation. Amy chatted happily along, as they walked, -for her heart was singing, but Tom's tongue had lost its function. He -did not hear what Amy was saying, and whenever she paused expectantly he -could only stammer an awkward assent, which was as often misplaced as -otherwise. He kept drifting to the rear of the schoolhouse, again and -again, to sear his eyeballs with the hateful spectacle there. He could -not help it. And it maddened him to see, as he thought he saw, that -Becky Thatcher never once suspected that he was even in the land of the -living. But she did see, nevertheless; and she knew she was winning her -fight, too, and was glad to see him suffer as she had suffered. - -Amy's happy prattle became intolerable. Tom hinted at things he had to -attend to; things that must be done; and time was fleeting. But in -vain--the girl chirped on. Tom thought, "Oh, hang her, ain't I ever -going to get rid of her?" At last he must be attending to those -things--and she said artlessly that she would be "around" when school -let out. And he hastened away, hating her for it. - -"Any other boy!" Tom thought, grating his teeth. "Any boy in the whole -town but that Saint Louis smarty that thinks he dresses so fine and is -aristocracy! Oh, all right, I licked you the first day you ever saw -this town, mister, and I'll lick you again! You just wait till I catch -you out! I'll just take and--" - -And he went through the motions of thrashing an imaginary boy ---pummelling the air, and kicking and gouging. "Oh, you do, do you? You -holler 'nough, do you? Now, then, let that learn you!" And so the -imaginary flogging was finished to his satisfaction. - -Tom fled home at noon. His conscience could not endure any more of -Amy's grateful happiness, and his jealousy could bear no more of the -other distress. Becky resumed her picture inspections with Alfred, but -as the minutes dragged along and no Tom came to suffer, her triumph -began to cloud and she lost interest; gravity and absent-mindedness -followed, and then melancholy; two or three times she pricked up her -ear at a footstep, but it was a false hope; no Tom came. At last she -grew entirely miserable and wished she hadn't carried it so far. When -poor Alfred, seeing that he was losing her, he did not know how, kept -exclaiming: "Oh, here's a jolly one! look at this!" she lost patience -at last, and said, "Oh, don't bother me! I don't care for them!" and -burst into tears, and got up and walked away. - -Alfred dropped alongside and was going to try to comfort her, but she -said: - -"Go away and leave me alone, can't you! I hate you!" - -So the boy halted, wondering what he could have done--for she had said -she would look at pictures all through the nooning--and she walked on, -crying. Then Alfred went musing into the deserted schoolhouse. He was -humiliated and angry. He easily guessed his way to the truth--the girl -had simply made a convenience of him to vent her spite upon Tom Sawyer. -He was far from hating Tom the less when this thought occurred to him. -He wished there was some way to get that boy into trouble without much -risk to himself. Tom's spelling-book fell under his eye. Here was his -opportunity. He gratefully opened to the lesson for the afternoon and -poured ink upon the page. - -Becky, glancing in at a window behind him at the moment, saw the act, -and moved on, without discovering herself. She started homeward, now, -intending to find Tom and tell him; Tom would be thankful and their -troubles would be healed. Before she was half way home, however, she -had changed her mind. The thought of Tom's treatment of her when she -was talking about her picnic came scorching back and filled her with -shame. She resolved to let him get whipped on the damaged -spelling-book's account, and to hate him forever, into the bargain. - - - -CHAPTER XIX - -TOM arrived at home in a dreary mood, and the first thing his aunt -said to him showed him that he had brought his sorrows to an -unpromising market: - -"Tom, I've a notion to skin you alive!" - -"Auntie, what have I done?" - -"Well, you've done enough. Here I go over to Sereny Harper, like an -old softy, expecting I'm going to make her believe all that rubbage -about that dream, when lo and behold you she'd found out from Joe that -you was over here and heard all the talk we had that night. Tom, I -don't know what is to become of a boy that will act like that. It makes -me feel so bad to think you could let me go to Sereny Harper and make -such a fool of myself and never say a word." - -This was a new aspect of the thing. His smartness of the morning had -seemed to Tom a good joke before, and very ingenious. It merely looked -mean and shabby now. He hung his head and could not think of anything -to say for a moment. Then he said: - -"Auntie, I wish I hadn't done it--but I didn't think." - -"Oh, child, you never think. You never think of anything but your own -selfishness. You could think to come all the way over here from -Jackson's Island in the night to laugh at our troubles, and you could -think to fool me with a lie about a dream; but you couldn't ever think -to pity us and save us from sorrow." - -"Auntie, I know now it was mean, but I didn't mean to be mean. I -didn't, honest. And besides, I didn't come over here to laugh at you -that night." - -"What did you come for, then?" - -"It was to tell you not to be uneasy about us, because we hadn't got -drownded." - -"Tom, Tom, I would be the thankfullest soul in this world if I could -believe you ever had as good a thought as that, but you know you never -did--and I know it, Tom." - -"Indeed and 'deed I did, auntie--I wish I may never stir if I didn't." - -"Oh, Tom, don't lie--don't do it. It only makes things a hundred times -worse." - -"It ain't a lie, auntie; it's the truth. I wanted to keep you from -grieving--that was all that made me come." - -"I'd give the whole world to believe that--it would cover up a power -of sins, Tom. I'd 'most be glad you'd run off and acted so bad. But it -ain't reasonable; because, why didn't you tell me, child?" - -"Why, you see, when you got to talking about the funeral, I just got -all full of the idea of our coming and hiding in the church, and I -couldn't somehow bear to spoil it. So I just put the bark back in my -pocket and kept mum." - -"What bark?" - -"The bark I had wrote on to tell you we'd gone pirating. I wish, now, -you'd waked up when I kissed you--I do, honest." - -The hard lines in his aunt's face relaxed and a sudden tenderness -dawned in her eyes. - -"DID you kiss me, Tom?" - -"Why, yes, I did." - -"Are you sure you did, Tom?" - -"Why, yes, I did, auntie--certain sure." - -"What did you kiss me for, Tom?" - -"Because I loved you so, and you laid there moaning and I was so sorry." - -The words sounded like truth. The old lady could not hide a tremor in -her voice when she said: - -"Kiss me again, Tom!--and be off with you to school, now, and don't -bother me any more." - -The moment he was gone, she ran to a closet and got out the ruin of a -jacket which Tom had gone pirating in. Then she stopped, with it in her -hand, and said to herself: - -"No, I don't dare. Poor boy, I reckon he's lied about it--but it's a -blessed, blessed lie, there's such a comfort come from it. I hope the -Lord--I KNOW the Lord will forgive him, because it was such -goodheartedness in him to tell it. But I don't want to find out it's a -lie. I won't look." - -She put the jacket away, and stood by musing a minute. Twice she put -out her hand to take the garment again, and twice she refrained. Once -more she ventured, and this time she fortified herself with the -thought: "It's a good lie--it's a good lie--I won't let it grieve me." -So she sought the jacket pocket. A moment later she was reading Tom's -piece of bark through flowing tears and saying: "I could forgive the -boy, now, if he'd committed a million sins!" - - - -CHAPTER XX - -THERE was something about Aunt Polly's manner, when she kissed Tom, -that swept away his low spirits and made him lighthearted and happy -again. He started to school and had the luck of coming upon Becky -Thatcher at the head of Meadow Lane. His mood always determined his -manner. Without a moment's hesitation he ran to her and said: - -"I acted mighty mean to-day, Becky, and I'm so sorry. I won't ever, -ever do that way again, as long as ever I live--please make up, won't -you?" - -The girl stopped and looked him scornfully in the face: - -"I'll thank you to keep yourself TO yourself, Mr. Thomas Sawyer. I'll -never speak to you again." - -She tossed her head and passed on. Tom was so stunned that he had not -even presence of mind enough to say "Who cares, Miss Smarty?" until the -right time to say it had gone by. So he said nothing. But he was in a -fine rage, nevertheless. He moped into the schoolyard wishing she were -a boy, and imagining how he would trounce her if she were. He presently -encountered her and delivered a stinging remark as he passed. She -hurled one in return, and the angry breach was complete. It seemed to -Becky, in her hot resentment, that she could hardly wait for school to -"take in," she was so impatient to see Tom flogged for the injured -spelling-book. If she had had any lingering notion of exposing Alfred -Temple, Tom's offensive fling had driven it entirely away. - -Poor girl, she did not know how fast she was nearing trouble herself. -The master, Mr. Dobbins, had reached middle age with an unsatisfied -ambition. The darling of his desires was, to be a doctor, but poverty -had decreed that he should be nothing higher than a village -schoolmaster. Every day he took a mysterious book out of his desk and -absorbed himself in it at times when no classes were reciting. He kept -that book under lock and key. There was not an urchin in school but was -perishing to have a glimpse of it, but the chance never came. Every boy -and girl had a theory about the nature of that book; but no two -theories were alike, and there was no way of getting at the facts in -the case. Now, as Becky was passing by the desk, which stood near the -door, she noticed that the key was in the lock! It was a precious -moment. She glanced around; found herself alone, and the next instant -she had the book in her hands. The title-page--Professor Somebody's -ANATOMY--carried no information to her mind; so she began to turn the -leaves. She came at once upon a handsomely engraved and colored -frontispiece--a human figure, stark naked. At that moment a shadow fell -on the page and Tom Sawyer stepped in at the door and caught a glimpse -of the picture. Becky snatched at the book to close it, and had the -hard luck to tear the pictured page half down the middle. She thrust -the volume into the desk, turned the key, and burst out crying with -shame and vexation. - -"Tom Sawyer, you are just as mean as you can be, to sneak up on a -person and look at what they're looking at." - -"How could I know you was looking at anything?" - -"You ought to be ashamed of yourself, Tom Sawyer; you know you're -going to tell on me, and oh, what shall I do, what shall I do! I'll be -whipped, and I never was whipped in school." - -Then she stamped her little foot and said: - -"BE so mean if you want to! I know something that's going to happen. -You just wait and you'll see! Hateful, hateful, hateful!"--and she -flung out of the house with a new explosion of crying. - -Tom stood still, rather flustered by this onslaught. Presently he said -to himself: - -"What a curious kind of a fool a girl is! Never been licked in school! -Shucks! What's a licking! That's just like a girl--they're so -thin-skinned and chicken-hearted. Well, of course I ain't going to tell -old Dobbins on this little fool, because there's other ways of getting -even on her, that ain't so mean; but what of it? Old Dobbins will ask -who it was tore his book. Nobody'll answer. Then he'll do just the way -he always does--ask first one and then t'other, and when he comes to the -right girl he'll know it, without any telling. Girls' faces always tell -on them. They ain't got any backbone. She'll get licked. Well, it's a -kind of a tight place for Becky Thatcher, because there ain't any way -out of it." Tom conned the thing a moment longer, and then added: "All -right, though; she'd like to see me in just such a fix--let her sweat it -out!" - -Tom joined the mob of skylarking scholars outside. In a few moments -the master arrived and school "took in." Tom did not feel a strong -interest in his studies. Every time he stole a glance at the girls' -side of the room Becky's face troubled him. Considering all things, he -did not want to pity her, and yet it was all he could do to help it. He -could get up no exultation that was really worthy the name. Presently -the spelling-book discovery was made, and Tom's mind was entirely full -of his own matters for a while after that. Becky roused up from her -lethargy of distress and showed good interest in the proceedings. She -did not expect that Tom could get out of his trouble by denying that he -spilt the ink on the book himself; and she was right. The denial only -seemed to make the thing worse for Tom. Becky supposed she would be -glad of that, and she tried to believe she was glad of it, but she -found she was not certain. When the worst came to the worst, she had an -impulse to get up and tell on Alfred Temple, but she made an effort and -forced herself to keep still--because, said she to herself, "he'll tell -about me tearing the picture sure. I wouldn't say a word, not to save -his life!" - -Tom took his whipping and went back to his seat not at all -broken-hearted, for he thought it was possible that he had unknowingly -upset the ink on the spelling-book himself, in some skylarking bout--he -had denied it for form's sake and because it was custom, and had stuck -to the denial from principle. - -A whole hour drifted by, the master sat nodding in his throne, the air -was drowsy with the hum of study. By and by, Mr. Dobbins straightened -himself up, yawned, then unlocked his desk, and reached for his book, -but seemed undecided whether to take it out or leave it. Most of the -pupils glanced up languidly, but there were two among them that watched -his movements with intent eyes. Mr. Dobbins fingered his book absently -for a while, then took it out and settled himself in his chair to read! -Tom shot a glance at Becky. He had seen a hunted and helpless rabbit -look as she did, with a gun levelled at its head. Instantly he forgot -his quarrel with her. Quick--something must be done! done in a flash, -too! But the very imminence of the emergency paralyzed his invention. -Good!--he had an inspiration! He would run and snatch the book, spring -through the door and fly. But his resolution shook for one little -instant, and the chance was lost--the master opened the volume. If Tom -only had the wasted opportunity back again! Too late. There was no help -for Becky now, he said. The next moment the master faced the school. -Every eye sank under his gaze. There was that in it which smote even -the innocent with fear. There was silence while one might count ten ---the master was gathering his wrath. Then he spoke: "Who tore this book?" - -There was not a sound. One could have heard a pin drop. The stillness -continued; the master searched face after face for signs of guilt. - -"Benjamin Rogers, did you tear this book?" - -A denial. Another pause. - -"Joseph Harper, did you?" - -Another denial. Tom's uneasiness grew more and more intense under the -slow torture of these proceedings. The master scanned the ranks of -boys--considered a while, then turned to the girls: - -"Amy Lawrence?" - -A shake of the head. - -"Gracie Miller?" - -The same sign. - -"Susan Harper, did you do this?" - -Another negative. The next girl was Becky Thatcher. Tom was trembling -from head to foot with excitement and a sense of the hopelessness of -the situation. - -"Rebecca Thatcher" [Tom glanced at her face--it was white with terror] ---"did you tear--no, look me in the face" [her hands rose in appeal] ---"did you tear this book?" - -A thought shot like lightning through Tom's brain. He sprang to his -feet and shouted--"I done it!" - -The school stared in perplexity at this incredible folly. Tom stood a -moment, to gather his dismembered faculties; and when he stepped -forward to go to his punishment the surprise, the gratitude, the -adoration that shone upon him out of poor Becky's eyes seemed pay -enough for a hundred floggings. Inspired by the splendor of his own -act, he took without an outcry the most merciless flaying that even Mr. -Dobbins had ever administered; and also received with indifference the -added cruelty of a command to remain two hours after school should be -dismissed--for he knew who would wait for him outside till his -captivity was done, and not count the tedious time as loss, either. - -Tom went to bed that night planning vengeance against Alfred Temple; -for with shame and repentance Becky had told him all, not forgetting -her own treachery; but even the longing for vengeance had to give way, -soon, to pleasanter musings, and he fell asleep at last with Becky's -latest words lingering dreamily in his ear-- - -"Tom, how COULD you be so noble!" - - - -CHAPTER XXI - -VACATION was approaching. The schoolmaster, always severe, grew -severer and more exacting than ever, for he wanted the school to make a -good showing on "Examination" day. His rod and his ferule were seldom -idle now--at least among the smaller pupils. Only the biggest boys, and -young ladies of eighteen and twenty, escaped lashing. Mr. Dobbins' -lashings were very vigorous ones, too; for although he carried, under -his wig, a perfectly bald and shiny head, he had only reached middle -age, and there was no sign of feebleness in his muscle. As the great -day approached, all the tyranny that was in him came to the surface; he -seemed to take a vindictive pleasure in punishing the least -shortcomings. The consequence was, that the smaller boys spent their -days in terror and suffering and their nights in plotting revenge. They -threw away no opportunity to do the master a mischief. But he kept -ahead all the time. The retribution that followed every vengeful -success was so sweeping and majestic that the boys always retired from -the field badly worsted. At last they conspired together and hit upon a -plan that promised a dazzling victory. They swore in the sign-painter's -boy, told him the scheme, and asked his help. He had his own reasons -for being delighted, for the master boarded in his father's family and -had given the boy ample cause to hate him. The master's wife would go -on a visit to the country in a few days, and there would be nothing to -interfere with the plan; the master always prepared himself for great -occasions by getting pretty well fuddled, and the sign-painter's boy -said that when the dominie had reached the proper condition on -Examination Evening he would "manage the thing" while he napped in his -chair; then he would have him awakened at the right time and hurried -away to school. - -In the fulness of time the interesting occasion arrived. At eight in -the evening the schoolhouse was brilliantly lighted, and adorned with -wreaths and festoons of foliage and flowers. The master sat throned in -his great chair upon a raised platform, with his blackboard behind him. -He was looking tolerably mellow. Three rows of benches on each side and -six rows in front of him were occupied by the dignitaries of the town -and by the parents of the pupils. To his left, back of the rows of -citizens, was a spacious temporary platform upon which were seated the -scholars who were to take part in the exercises of the evening; rows of -small boys, washed and dressed to an intolerable state of discomfort; -rows of gawky big boys; snowbanks of girls and young ladies clad in -lawn and muslin and conspicuously conscious of their bare arms, their -grandmothers' ancient trinkets, their bits of pink and blue ribbon and -the flowers in their hair. All the rest of the house was filled with -non-participating scholars. - -The exercises began. A very little boy stood up and sheepishly -recited, "You'd scarce expect one of my age to speak in public on the -stage," etc.--accompanying himself with the painfully exact and -spasmodic gestures which a machine might have used--supposing the -machine to be a trifle out of order. But he got through safely, though -cruelly scared, and got a fine round of applause when he made his -manufactured bow and retired. - -A little shamefaced girl lisped, "Mary had a little lamb," etc., -performed a compassion-inspiring curtsy, got her meed of applause, and -sat down flushed and happy. - -Tom Sawyer stepped forward with conceited confidence and soared into -the unquenchable and indestructible "Give me liberty or give me death" -speech, with fine fury and frantic gesticulation, and broke down in the -middle of it. A ghastly stage-fright seized him, his legs quaked under -him and he was like to choke. True, he had the manifest sympathy of the -house but he had the house's silence, too, which was even worse than -its sympathy. The master frowned, and this completed the disaster. Tom -struggled awhile and then retired, utterly defeated. There was a weak -attempt at applause, but it died early. - -"The Boy Stood on the Burning Deck" followed; also "The Assyrian Came -Down," and other declamatory gems. Then there were reading exercises, -and a spelling fight. The meagre Latin class recited with honor. The -prime feature of the evening was in order, now--original "compositions" -by the young ladies. Each in her turn stepped forward to the edge of -the platform, cleared her throat, held up her manuscript (tied with -dainty ribbon), and proceeded to read, with labored attention to -"expression" and punctuation. The themes were the same that had been -illuminated upon similar occasions by their mothers before them, their -grandmothers, and doubtless all their ancestors in the female line -clear back to the Crusades. "Friendship" was one; "Memories of Other -Days"; "Religion in History"; "Dream Land"; "The Advantages of -Culture"; "Forms of Political Government Compared and Contrasted"; -"Melancholy"; "Filial Love"; "Heart Longings," etc., etc. - -A prevalent feature in these compositions was a nursed and petted -melancholy; another was a wasteful and opulent gush of "fine language"; -another was a tendency to lug in by the ears particularly prized words -and phrases until they were worn entirely out; and a peculiarity that -conspicuously marked and marred them was the inveterate and intolerable -sermon that wagged its crippled tail at the end of each and every one -of them. No matter what the subject might be, a brain-racking effort -was made to squirm it into some aspect or other that the moral and -religious mind could contemplate with edification. The glaring -insincerity of these sermons was not sufficient to compass the -banishment of the fashion from the schools, and it is not sufficient -to-day; it never will be sufficient while the world stands, perhaps. -There is no school in all our land where the young ladies do not feel -obliged to close their compositions with a sermon; and you will find -that the sermon of the most frivolous and the least religious girl in -the school is always the longest and the most relentlessly pious. But -enough of this. Homely truth is unpalatable. - -Let us return to the "Examination." The first composition that was -read was one entitled "Is this, then, Life?" Perhaps the reader can -endure an extract from it: - - "In the common walks of life, with what delightful - emotions does the youthful mind look forward to some - anticipated scene of festivity! Imagination is busy - sketching rose-tinted pictures of joy. In fancy, the - voluptuous votary of fashion sees herself amid the - festive throng, 'the observed of all observers.' Her - graceful form, arrayed in snowy robes, is whirling - through the mazes of the joyous dance; her eye is - brightest, her step is lightest in the gay assembly. - - "In such delicious fancies time quickly glides by, - and the welcome hour arrives for her entrance into - the Elysian world, of which she has had such bright - dreams. How fairy-like does everything appear to - her enchanted vision! Each new scene is more charming - than the last. But after a while she finds that - beneath this goodly exterior, all is vanity, the - flattery which once charmed her soul, now grates - harshly upon her ear; the ball-room has lost its - charms; and with wasted health and imbittered heart, - she turns away with the conviction that earthly - pleasures cannot satisfy the longings of the soul!" - -And so forth and so on. There was a buzz of gratification from time to -time during the reading, accompanied by whispered ejaculations of "How -sweet!" "How eloquent!" "So true!" etc., and after the thing had closed -with a peculiarly afflicting sermon the applause was enthusiastic. - -Then arose a slim, melancholy girl, whose face had the "interesting" -paleness that comes of pills and indigestion, and read a "poem." Two -stanzas of it will do: - - "A MISSOURI MAIDEN'S FAREWELL TO ALABAMA - - "Alabama, good-bye! I love thee well! - But yet for a while do I leave thee now! - Sad, yes, sad thoughts of thee my heart doth swell, - And burning recollections throng my brow! - For I have wandered through thy flowery woods; - Have roamed and read near Tallapoosa's stream; - Have listened to Tallassee's warring floods, - And wooed on Coosa's side Aurora's beam. - - "Yet shame I not to bear an o'er-full heart, - Nor blush to turn behind my tearful eyes; - 'Tis from no stranger land I now must part, - 'Tis to no strangers left I yield these sighs. - Welcome and home were mine within this State, - Whose vales I leave--whose spires fade fast from me - And cold must be mine eyes, and heart, and tete, - When, dear Alabama! they turn cold on thee!" - -There were very few there who knew what "tete" meant, but the poem was -very satisfactory, nevertheless. - -Next appeared a dark-complexioned, black-eyed, black-haired young -lady, who paused an impressive moment, assumed a tragic expression, and -began to read in a measured, solemn tone: - - "A VISION - - "Dark and tempestuous was night. Around the - throne on high not a single star quivered; but - the deep intonations of the heavy thunder - constantly vibrated upon the ear; whilst the - terrific lightning revelled in angry mood - through the cloudy chambers of heaven, seeming - to scorn the power exerted over its terror by - the illustrious Franklin! Even the boisterous - winds unanimously came forth from their mystic - homes, and blustered about as if to enhance by - their aid the wildness of the scene. - - "At such a time, so dark, so dreary, for human - sympathy my very spirit sighed; but instead thereof, - - "'My dearest friend, my counsellor, my comforter - and guide--My joy in grief, my second bliss - in joy,' came to my side. She moved like one of - those bright beings pictured in the sunny walks - of fancy's Eden by the romantic and young, a - queen of beauty unadorned save by her own - transcendent loveliness. So soft was her step, it - failed to make even a sound, and but for the - magical thrill imparted by her genial touch, as - other unobtrusive beauties, she would have glided - away un-perceived--unsought. A strange sadness - rested upon her features, like icy tears upon - the robe of December, as she pointed to the - contending elements without, and bade me contemplate - the two beings presented." - -This nightmare occupied some ten pages of manuscript and wound up with -a sermon so destructive of all hope to non-Presbyterians that it took -the first prize. This composition was considered to be the very finest -effort of the evening. The mayor of the village, in delivering the -prize to the author of it, made a warm speech in which he said that it -was by far the most "eloquent" thing he had ever listened to, and that -Daniel Webster himself might well be proud of it. - -It may be remarked, in passing, that the number of compositions in -which the word "beauteous" was over-fondled, and human experience -referred to as "life's page," was up to the usual average. - -Now the master, mellow almost to the verge of geniality, put his chair -aside, turned his back to the audience, and began to draw a map of -America on the blackboard, to exercise the geography class upon. But he -made a sad business of it with his unsteady hand, and a smothered -titter rippled over the house. He knew what the matter was, and set -himself to right it. He sponged out lines and remade them; but he only -distorted them more than ever, and the tittering was more pronounced. -He threw his entire attention upon his work, now, as if determined not -to be put down by the mirth. He felt that all eyes were fastened upon -him; he imagined he was succeeding, and yet the tittering continued; it -even manifestly increased. And well it might. There was a garret above, -pierced with a scuttle over his head; and down through this scuttle -came a cat, suspended around the haunches by a string; she had a rag -tied about her head and jaws to keep her from mewing; as she slowly -descended she curved upward and clawed at the string, she swung -downward and clawed at the intangible air. The tittering rose higher -and higher--the cat was within six inches of the absorbed teacher's -head--down, down, a little lower, and she grabbed his wig with her -desperate claws, clung to it, and was snatched up into the garret in an -instant with her trophy still in her possession! And how the light did -blaze abroad from the master's bald pate--for the sign-painter's boy -had GILDED it! - -That broke up the meeting. The boys were avenged. Vacation had come. - - NOTE:--The pretended "compositions" quoted in - this chapter are taken without alteration from a - volume entitled "Prose and Poetry, by a Western - Lady"--but they are exactly and precisely after - the schoolgirl pattern, and hence are much - happier than any mere imitations could be. - - - -CHAPTER XXII - -TOM joined the new order of Cadets of Temperance, being attracted by -the showy character of their "regalia." He promised to abstain from -smoking, chewing, and profanity as long as he remained a member. Now he -found out a new thing--namely, that to promise not to do a thing is the -surest way in the world to make a body want to go and do that very -thing. Tom soon found himself tormented with a desire to drink and -swear; the desire grew to be so intense that nothing but the hope of a -chance to display himself in his red sash kept him from withdrawing -from the order. Fourth of July was coming; but he soon gave that up ---gave it up before he had worn his shackles over forty-eight hours--and -fixed his hopes upon old Judge Frazer, justice of the peace, who was -apparently on his deathbed and would have a big public funeral, since -he was so high an official. During three days Tom was deeply concerned -about the Judge's condition and hungry for news of it. Sometimes his -hopes ran high--so high that he would venture to get out his regalia -and practise before the looking-glass. But the Judge had a most -discouraging way of fluctuating. At last he was pronounced upon the -mend--and then convalescent. Tom was disgusted; and felt a sense of -injury, too. He handed in his resignation at once--and that night the -Judge suffered a relapse and died. Tom resolved that he would never -trust a man like that again. - -The funeral was a fine thing. The Cadets paraded in a style calculated -to kill the late member with envy. Tom was a free boy again, however ---there was something in that. He could drink and swear, now--but found -to his surprise that he did not want to. The simple fact that he could, -took the desire away, and the charm of it. - -Tom presently wondered to find that his coveted vacation was beginning -to hang a little heavily on his hands. - -He attempted a diary--but nothing happened during three days, and so -he abandoned it. - -The first of all the negro minstrel shows came to town, and made a -sensation. Tom and Joe Harper got up a band of performers and were -happy for two days. - -Even the Glorious Fourth was in some sense a failure, for it rained -hard, there was no procession in consequence, and the greatest man in -the world (as Tom supposed), Mr. Benton, an actual United States -Senator, proved an overwhelming disappointment--for he was not -twenty-five feet high, nor even anywhere in the neighborhood of it. - -A circus came. The boys played circus for three days afterward in -tents made of rag carpeting--admission, three pins for boys, two for -girls--and then circusing was abandoned. - -A phrenologist and a mesmerizer came--and went again and left the -village duller and drearier than ever. - -There were some boys-and-girls' parties, but they were so few and so -delightful that they only made the aching voids between ache the harder. - -Becky Thatcher was gone to her Constantinople home to stay with her -parents during vacation--so there was no bright side to life anywhere. - -The dreadful secret of the murder was a chronic misery. It was a very -cancer for permanency and pain. - -Then came the measles. - -During two long weeks Tom lay a prisoner, dead to the world and its -happenings. He was very ill, he was interested in nothing. When he got -upon his feet at last and moved feebly down-town, a melancholy change -had come over everything and every creature. There had been a -"revival," and everybody had "got religion," not only the adults, but -even the boys and girls. Tom went about, hoping against hope for the -sight of one blessed sinful face, but disappointment crossed him -everywhere. He found Joe Harper studying a Testament, and turned sadly -away from the depressing spectacle. He sought Ben Rogers, and found him -visiting the poor with a basket of tracts. He hunted up Jim Hollis, who -called his attention to the precious blessing of his late measles as a -warning. Every boy he encountered added another ton to his depression; -and when, in desperation, he flew for refuge at last to the bosom of -Huckleberry Finn and was received with a Scriptural quotation, his -heart broke and he crept home and to bed realizing that he alone of all -the town was lost, forever and forever. - -And that night there came on a terrific storm, with driving rain, -awful claps of thunder and blinding sheets of lightning. He covered his -head with the bedclothes and waited in a horror of suspense for his -doom; for he had not the shadow of a doubt that all this hubbub was -about him. He believed he had taxed the forbearance of the powers above -to the extremity of endurance and that this was the result. It might -have seemed to him a waste of pomp and ammunition to kill a bug with a -battery of artillery, but there seemed nothing incongruous about the -getting up such an expensive thunderstorm as this to knock the turf -from under an insect like himself. - -By and by the tempest spent itself and died without accomplishing its -object. The boy's first impulse was to be grateful, and reform. His -second was to wait--for there might not be any more storms. - -The next day the doctors were back; Tom had relapsed. The three weeks -he spent on his back this time seemed an entire age. When he got abroad -at last he was hardly grateful that he had been spared, remembering how -lonely was his estate, how companionless and forlorn he was. He drifted -listlessly down the street and found Jim Hollis acting as judge in a -juvenile court that was trying a cat for murder, in the presence of her -victim, a bird. He found Joe Harper and Huck Finn up an alley eating a -stolen melon. Poor lads! they--like Tom--had suffered a relapse. - - - -CHAPTER XXIII - -AT last the sleepy atmosphere was stirred--and vigorously: the murder -trial came on in the court. It became the absorbing topic of village -talk immediately. Tom could not get away from it. Every reference to -the murder sent a shudder to his heart, for his troubled conscience and -fears almost persuaded him that these remarks were put forth in his -hearing as "feelers"; he did not see how he could be suspected of -knowing anything about the murder, but still he could not be -comfortable in the midst of this gossip. It kept him in a cold shiver -all the time. He took Huck to a lonely place to have a talk with him. -It would be some relief to unseal his tongue for a little while; to -divide his burden of distress with another sufferer. Moreover, he -wanted to assure himself that Huck had remained discreet. - -"Huck, have you ever told anybody about--that?" - -"'Bout what?" - -"You know what." - -"Oh--'course I haven't." - -"Never a word?" - -"Never a solitary word, so help me. What makes you ask?" - -"Well, I was afeard." - -"Why, Tom Sawyer, we wouldn't be alive two days if that got found out. -YOU know that." - -Tom felt more comfortable. After a pause: - -"Huck, they couldn't anybody get you to tell, could they?" - -"Get me to tell? Why, if I wanted that half-breed devil to drownd me -they could get me to tell. They ain't no different way." - -"Well, that's all right, then. I reckon we're safe as long as we keep -mum. But let's swear again, anyway. It's more surer." - -"I'm agreed." - -So they swore again with dread solemnities. - -"What is the talk around, Huck? I've heard a power of it." - -"Talk? Well, it's just Muff Potter, Muff Potter, Muff Potter all the -time. It keeps me in a sweat, constant, so's I want to hide som'ers." - -"That's just the same way they go on round me. I reckon he's a goner. -Don't you feel sorry for him, sometimes?" - -"Most always--most always. He ain't no account; but then he hain't -ever done anything to hurt anybody. Just fishes a little, to get money -to get drunk on--and loafs around considerable; but lord, we all do -that--leastways most of us--preachers and such like. But he's kind of -good--he give me half a fish, once, when there warn't enough for two; -and lots of times he's kind of stood by me when I was out of luck." - -"Well, he's mended kites for me, Huck, and knitted hooks on to my -line. I wish we could get him out of there." - -"My! we couldn't get him out, Tom. And besides, 'twouldn't do any -good; they'd ketch him again." - -"Yes--so they would. But I hate to hear 'em abuse him so like the -dickens when he never done--that." - -"I do too, Tom. Lord, I hear 'em say he's the bloodiest looking -villain in this country, and they wonder he wasn't ever hung before." - -"Yes, they talk like that, all the time. I've heard 'em say that if he -was to get free they'd lynch him." - -"And they'd do it, too." - -The boys had a long talk, but it brought them little comfort. As the -twilight drew on, they found themselves hanging about the neighborhood -of the little isolated jail, perhaps with an undefined hope that -something would happen that might clear away their difficulties. But -nothing happened; there seemed to be no angels or fairies interested in -this luckless captive. - -The boys did as they had often done before--went to the cell grating -and gave Potter some tobacco and matches. He was on the ground floor -and there were no guards. - -His gratitude for their gifts had always smote their consciences -before--it cut deeper than ever, this time. They felt cowardly and -treacherous to the last degree when Potter said: - -"You've been mighty good to me, boys--better'n anybody else in this -town. And I don't forget it, I don't. Often I says to myself, says I, -'I used to mend all the boys' kites and things, and show 'em where the -good fishin' places was, and befriend 'em what I could, and now they've -all forgot old Muff when he's in trouble; but Tom don't, and Huck -don't--THEY don't forget him, says I, 'and I don't forget them.' Well, -boys, I done an awful thing--drunk and crazy at the time--that's the -only way I account for it--and now I got to swing for it, and it's -right. Right, and BEST, too, I reckon--hope so, anyway. Well, we won't -talk about that. I don't want to make YOU feel bad; you've befriended -me. But what I want to say, is, don't YOU ever get drunk--then you won't -ever get here. Stand a litter furder west--so--that's it; it's a prime -comfort to see faces that's friendly when a body's in such a muck of -trouble, and there don't none come here but yourn. Good friendly -faces--good friendly faces. Git up on one another's backs and let me -touch 'em. That's it. Shake hands--yourn'll come through the bars, but -mine's too big. Little hands, and weak--but they've helped Muff Potter -a power, and they'd help him more if they could." - -Tom went home miserable, and his dreams that night were full of -horrors. The next day and the day after, he hung about the court-room, -drawn by an almost irresistible impulse to go in, but forcing himself -to stay out. Huck was having the same experience. They studiously -avoided each other. Each wandered away, from time to time, but the same -dismal fascination always brought them back presently. Tom kept his -ears open when idlers sauntered out of the court-room, but invariably -heard distressing news--the toils were closing more and more -relentlessly around poor Potter. At the end of the second day the -village talk was to the effect that Injun Joe's evidence stood firm and -unshaken, and that there was not the slightest question as to what the -jury's verdict would be. - -Tom was out late, that night, and came to bed through the window. He -was in a tremendous state of excitement. It was hours before he got to -sleep. All the village flocked to the court-house the next morning, for -this was to be the great day. Both sexes were about equally represented -in the packed audience. After a long wait the jury filed in and took -their places; shortly afterward, Potter, pale and haggard, timid and -hopeless, was brought in, with chains upon him, and seated where all -the curious eyes could stare at him; no less conspicuous was Injun Joe, -stolid as ever. There was another pause, and then the judge arrived and -the sheriff proclaimed the opening of the court. The usual whisperings -among the lawyers and gathering together of papers followed. These -details and accompanying delays worked up an atmosphere of preparation -that was as impressive as it was fascinating. - -Now a witness was called who testified that he found Muff Potter -washing in the brook, at an early hour of the morning that the murder -was discovered, and that he immediately sneaked away. After some -further questioning, counsel for the prosecution said: - -"Take the witness." - -The prisoner raised his eyes for a moment, but dropped them again when -his own counsel said: - -"I have no questions to ask him." - -The next witness proved the finding of the knife near the corpse. -Counsel for the prosecution said: - -"Take the witness." - -"I have no questions to ask him," Potter's lawyer replied. - -A third witness swore he had often seen the knife in Potter's -possession. - -"Take the witness." - -Counsel for Potter declined to question him. The faces of the audience -began to betray annoyance. Did this attorney mean to throw away his -client's life without an effort? - -Several witnesses deposed concerning Potter's guilty behavior when -brought to the scene of the murder. They were allowed to leave the -stand without being cross-questioned. - -Every detail of the damaging circumstances that occurred in the -graveyard upon that morning which all present remembered so well was -brought out by credible witnesses, but none of them were cross-examined -by Potter's lawyer. The perplexity and dissatisfaction of the house -expressed itself in murmurs and provoked a reproof from the bench. -Counsel for the prosecution now said: - -"By the oaths of citizens whose simple word is above suspicion, we -have fastened this awful crime, beyond all possibility of question, -upon the unhappy prisoner at the bar. We rest our case here." - -A groan escaped from poor Potter, and he put his face in his hands and -rocked his body softly to and fro, while a painful silence reigned in -the court-room. Many men were moved, and many women's compassion -testified itself in tears. Counsel for the defence rose and said: - -"Your honor, in our remarks at the opening of this trial, we -foreshadowed our purpose to prove that our client did this fearful deed -while under the influence of a blind and irresponsible delirium -produced by drink. We have changed our mind. We shall not offer that -plea." [Then to the clerk:] "Call Thomas Sawyer!" - -A puzzled amazement awoke in every face in the house, not even -excepting Potter's. Every eye fastened itself with wondering interest -upon Tom as he rose and took his place upon the stand. The boy looked -wild enough, for he was badly scared. The oath was administered. - -"Thomas Sawyer, where were you on the seventeenth of June, about the -hour of midnight?" - -Tom glanced at Injun Joe's iron face and his tongue failed him. The -audience listened breathless, but the words refused to come. After a -few moments, however, the boy got a little of his strength back, and -managed to put enough of it into his voice to make part of the house -hear: - -"In the graveyard!" - -"A little bit louder, please. Don't be afraid. You were--" - -"In the graveyard." - -A contemptuous smile flitted across Injun Joe's face. - -"Were you anywhere near Horse Williams' grave?" - -"Yes, sir." - -"Speak up--just a trifle louder. How near were you?" - -"Near as I am to you." - -"Were you hidden, or not?" - -"I was hid." - -"Where?" - -"Behind the elms that's on the edge of the grave." - -Injun Joe gave a barely perceptible start. - -"Any one with you?" - -"Yes, sir. I went there with--" - -"Wait--wait a moment. Never mind mentioning your companion's name. We -will produce him at the proper time. Did you carry anything there with -you." - -Tom hesitated and looked confused. - -"Speak out, my boy--don't be diffident. The truth is always -respectable. What did you take there?" - -"Only a--a--dead cat." - -There was a ripple of mirth, which the court checked. - -"We will produce the skeleton of that cat. Now, my boy, tell us -everything that occurred--tell it in your own way--don't skip anything, -and don't be afraid." - -Tom began--hesitatingly at first, but as he warmed to his subject his -words flowed more and more easily; in a little while every sound ceased -but his own voice; every eye fixed itself upon him; with parted lips -and bated breath the audience hung upon his words, taking no note of -time, rapt in the ghastly fascinations of the tale. The strain upon -pent emotion reached its climax when the boy said: - -"--and as the doctor fetched the board around and Muff Potter fell, -Injun Joe jumped with the knife and--" - -Crash! Quick as lightning the half-breed sprang for a window, tore his -way through all opposers, and was gone! - - - -CHAPTER XXIV - -TOM was a glittering hero once more--the pet of the old, the envy of -the young. His name even went into immortal print, for the village -paper magnified him. There were some that believed he would be -President, yet, if he escaped hanging. - -As usual, the fickle, unreasoning world took Muff Potter to its bosom -and fondled him as lavishly as it had abused him before. But that sort -of conduct is to the world's credit; therefore it is not well to find -fault with it. - -Tom's days were days of splendor and exultation to him, but his nights -were seasons of horror. Injun Joe infested all his dreams, and always -with doom in his eye. Hardly any temptation could persuade the boy to -stir abroad after nightfall. Poor Huck was in the same state of -wretchedness and terror, for Tom had told the whole story to the lawyer -the night before the great day of the trial, and Huck was sore afraid -that his share in the business might leak out, yet, notwithstanding -Injun Joe's flight had saved him the suffering of testifying in court. -The poor fellow had got the attorney to promise secrecy, but what of -that? Since Tom's harassed conscience had managed to drive him to the -lawyer's house by night and wring a dread tale from lips that had been -sealed with the dismalest and most formidable of oaths, Huck's -confidence in the human race was well-nigh obliterated. - -Daily Muff Potter's gratitude made Tom glad he had spoken; but nightly -he wished he had sealed up his tongue. - -Half the time Tom was afraid Injun Joe would never be captured; the -other half he was afraid he would be. He felt sure he never could draw -a safe breath again until that man was dead and he had seen the corpse. - -Rewards had been offered, the country had been scoured, but no Injun -Joe was found. One of those omniscient and awe-inspiring marvels, a -detective, came up from St. Louis, moused around, shook his head, -looked wise, and made that sort of astounding success which members of -that craft usually achieve. That is to say, he "found a clew." But you -can't hang a "clew" for murder, and so after that detective had got -through and gone home, Tom felt just as insecure as he was before. - -The slow days drifted on, and each left behind it a slightly lightened -weight of apprehension. - - - -CHAPTER XXV - -THERE comes a time in every rightly-constructed boy's life when he has -a raging desire to go somewhere and dig for hidden treasure. This -desire suddenly came upon Tom one day. He sallied out to find Joe -Harper, but failed of success. Next he sought Ben Rogers; he had gone -fishing. Presently he stumbled upon Huck Finn the Red-Handed. Huck -would answer. Tom took him to a private place and opened the matter to -him confidentially. Huck was willing. Huck was always willing to take a -hand in any enterprise that offered entertainment and required no -capital, for he had a troublesome superabundance of that sort of time -which is not money. "Where'll we dig?" said Huck. - -"Oh, most anywhere." - -"Why, is it hid all around?" - -"No, indeed it ain't. It's hid in mighty particular places, Huck ---sometimes on islands, sometimes in rotten chests under the end of a -limb of an old dead tree, just where the shadow falls at midnight; but -mostly under the floor in ha'nted houses." - -"Who hides it?" - -"Why, robbers, of course--who'd you reckon? Sunday-school -sup'rintendents?" - -"I don't know. If 'twas mine I wouldn't hide it; I'd spend it and have -a good time." - -"So would I. But robbers don't do that way. They always hide it and -leave it there." - -"Don't they come after it any more?" - -"No, they think they will, but they generally forget the marks, or -else they die. Anyway, it lays there a long time and gets rusty; and by -and by somebody finds an old yellow paper that tells how to find the -marks--a paper that's got to be ciphered over about a week because it's -mostly signs and hy'roglyphics." - -"Hyro--which?" - -"Hy'roglyphics--pictures and things, you know, that don't seem to mean -anything." - -"Have you got one of them papers, Tom?" - -"No." - -"Well then, how you going to find the marks?" - -"I don't want any marks. They always bury it under a ha'nted house or -on an island, or under a dead tree that's got one limb sticking out. -Well, we've tried Jackson's Island a little, and we can try it again -some time; and there's the old ha'nted house up the Still-House branch, -and there's lots of dead-limb trees--dead loads of 'em." - -"Is it under all of them?" - -"How you talk! No!" - -"Then how you going to know which one to go for?" - -"Go for all of 'em!" - -"Why, Tom, it'll take all summer." - -"Well, what of that? Suppose you find a brass pot with a hundred -dollars in it, all rusty and gray, or rotten chest full of di'monds. -How's that?" - -Huck's eyes glowed. - -"That's bully. Plenty bully enough for me. Just you gimme the hundred -dollars and I don't want no di'monds." - -"All right. But I bet you I ain't going to throw off on di'monds. Some -of 'em's worth twenty dollars apiece--there ain't any, hardly, but's -worth six bits or a dollar." - -"No! Is that so?" - -"Cert'nly--anybody'll tell you so. Hain't you ever seen one, Huck?" - -"Not as I remember." - -"Oh, kings have slathers of them." - -"Well, I don' know no kings, Tom." - -"I reckon you don't. But if you was to go to Europe you'd see a raft -of 'em hopping around." - -"Do they hop?" - -"Hop?--your granny! No!" - -"Well, what did you say they did, for?" - -"Shucks, I only meant you'd SEE 'em--not hopping, of course--what do -they want to hop for?--but I mean you'd just see 'em--scattered around, -you know, in a kind of a general way. Like that old humpbacked Richard." - -"Richard? What's his other name?" - -"He didn't have any other name. Kings don't have any but a given name." - -"No?" - -"But they don't." - -"Well, if they like it, Tom, all right; but I don't want to be a king -and have only just a given name, like a nigger. But say--where you -going to dig first?" - -"Well, I don't know. S'pose we tackle that old dead-limb tree on the -hill t'other side of Still-House branch?" - -"I'm agreed." - -So they got a crippled pick and a shovel, and set out on their -three-mile tramp. They arrived hot and panting, and threw themselves -down in the shade of a neighboring elm to rest and have a smoke. - -"I like this," said Tom. - -"So do I." - -"Say, Huck, if we find a treasure here, what you going to do with your -share?" - -"Well, I'll have pie and a glass of soda every day, and I'll go to -every circus that comes along. I bet I'll have a gay time." - -"Well, ain't you going to save any of it?" - -"Save it? What for?" - -"Why, so as to have something to live on, by and by." - -"Oh, that ain't any use. Pap would come back to thish-yer town some -day and get his claws on it if I didn't hurry up, and I tell you he'd -clean it out pretty quick. What you going to do with yourn, Tom?" - -"I'm going to buy a new drum, and a sure-'nough sword, and a red -necktie and a bull pup, and get married." - -"Married!" - -"That's it." - -"Tom, you--why, you ain't in your right mind." - -"Wait--you'll see." - -"Well, that's the foolishest thing you could do. Look at pap and my -mother. Fight! Why, they used to fight all the time. I remember, mighty -well." - -"That ain't anything. The girl I'm going to marry won't fight." - -"Tom, I reckon they're all alike. They'll all comb a body. Now you -better think 'bout this awhile. I tell you you better. What's the name -of the gal?" - -"It ain't a gal at all--it's a girl." - -"It's all the same, I reckon; some says gal, some says girl--both's -right, like enough. Anyway, what's her name, Tom?" - -"I'll tell you some time--not now." - -"All right--that'll do. Only if you get married I'll be more lonesomer -than ever." - -"No you won't. You'll come and live with me. Now stir out of this and -we'll go to digging." - -They worked and sweated for half an hour. No result. They toiled -another half-hour. Still no result. Huck said: - -"Do they always bury it as deep as this?" - -"Sometimes--not always. Not generally. I reckon we haven't got the -right place." - -So they chose a new spot and began again. The labor dragged a little, -but still they made progress. They pegged away in silence for some -time. Finally Huck leaned on his shovel, swabbed the beaded drops from -his brow with his sleeve, and said: - -"Where you going to dig next, after we get this one?" - -"I reckon maybe we'll tackle the old tree that's over yonder on -Cardiff Hill back of the widow's." - -"I reckon that'll be a good one. But won't the widow take it away from -us, Tom? It's on her land." - -"SHE take it away! Maybe she'd like to try it once. Whoever finds one -of these hid treasures, it belongs to him. It don't make any difference -whose land it's on." - -That was satisfactory. The work went on. By and by Huck said: - -"Blame it, we must be in the wrong place again. What do you think?" - -"It is mighty curious, Huck. I don't understand it. Sometimes witches -interfere. I reckon maybe that's what's the trouble now." - -"Shucks! Witches ain't got no power in the daytime." - -"Well, that's so. I didn't think of that. Oh, I know what the matter -is! What a blamed lot of fools we are! You got to find out where the -shadow of the limb falls at midnight, and that's where you dig!" - -"Then consound it, we've fooled away all this work for nothing. Now -hang it all, we got to come back in the night. It's an awful long way. -Can you get out?" - -"I bet I will. We've got to do it to-night, too, because if somebody -sees these holes they'll know in a minute what's here and they'll go -for it." - -"Well, I'll come around and maow to-night." - -"All right. Let's hide the tools in the bushes." - -The boys were there that night, about the appointed time. They sat in -the shadow waiting. It was a lonely place, and an hour made solemn by -old traditions. Spirits whispered in the rustling leaves, ghosts lurked -in the murky nooks, the deep baying of a hound floated up out of the -distance, an owl answered with his sepulchral note. The boys were -subdued by these solemnities, and talked little. By and by they judged -that twelve had come; they marked where the shadow fell, and began to -dig. Their hopes commenced to rise. Their interest grew stronger, and -their industry kept pace with it. The hole deepened and still deepened, -but every time their hearts jumped to hear the pick strike upon -something, they only suffered a new disappointment. It was only a stone -or a chunk. At last Tom said: - -"It ain't any use, Huck, we're wrong again." - -"Well, but we CAN'T be wrong. We spotted the shadder to a dot." - -"I know it, but then there's another thing." - -"What's that?". - -"Why, we only guessed at the time. Like enough it was too late or too -early." - -Huck dropped his shovel. - -"That's it," said he. "That's the very trouble. We got to give this -one up. We can't ever tell the right time, and besides this kind of -thing's too awful, here this time of night with witches and ghosts -a-fluttering around so. I feel as if something's behind me all the time; -and I'm afeard to turn around, becuz maybe there's others in front -a-waiting for a chance. I been creeping all over, ever since I got here." - -"Well, I've been pretty much so, too, Huck. They most always put in a -dead man when they bury a treasure under a tree, to look out for it." - -"Lordy!" - -"Yes, they do. I've always heard that." - -"Tom, I don't like to fool around much where there's dead people. A -body's bound to get into trouble with 'em, sure." - -"I don't like to stir 'em up, either. S'pose this one here was to -stick his skull out and say something!" - -"Don't Tom! It's awful." - -"Well, it just is. Huck, I don't feel comfortable a bit." - -"Say, Tom, let's give this place up, and try somewheres else." - -"All right, I reckon we better." - -"What'll it be?" - -Tom considered awhile; and then said: - -"The ha'nted house. That's it!" - -"Blame it, I don't like ha'nted houses, Tom. Why, they're a dern sight -worse'n dead people. Dead people might talk, maybe, but they don't come -sliding around in a shroud, when you ain't noticing, and peep over your -shoulder all of a sudden and grit their teeth, the way a ghost does. I -couldn't stand such a thing as that, Tom--nobody could." - -"Yes, but, Huck, ghosts don't travel around only at night. They won't -hender us from digging there in the daytime." - -"Well, that's so. But you know mighty well people don't go about that -ha'nted house in the day nor the night." - -"Well, that's mostly because they don't like to go where a man's been -murdered, anyway--but nothing's ever been seen around that house except -in the night--just some blue lights slipping by the windows--no regular -ghosts." - -"Well, where you see one of them blue lights flickering around, Tom, -you can bet there's a ghost mighty close behind it. It stands to -reason. Becuz you know that they don't anybody but ghosts use 'em." - -"Yes, that's so. But anyway they don't come around in the daytime, so -what's the use of our being afeard?" - -"Well, all right. We'll tackle the ha'nted house if you say so--but I -reckon it's taking chances." - -They had started down the hill by this time. There in the middle of -the moonlit valley below them stood the "ha'nted" house, utterly -isolated, its fences gone long ago, rank weeds smothering the very -doorsteps, the chimney crumbled to ruin, the window-sashes vacant, a -corner of the roof caved in. The boys gazed awhile, half expecting to -see a blue light flit past a window; then talking in a low tone, as -befitted the time and the circumstances, they struck far off to the -right, to give the haunted house a wide berth, and took their way -homeward through the woods that adorned the rearward side of Cardiff -Hill. - - - -CHAPTER XXVI - -ABOUT noon the next day the boys arrived at the dead tree; they had -come for their tools. Tom was impatient to go to the haunted house; -Huck was measurably so, also--but suddenly said: - -"Lookyhere, Tom, do you know what day it is?" - -Tom mentally ran over the days of the week, and then quickly lifted -his eyes with a startled look in them-- - -"My! I never once thought of it, Huck!" - -"Well, I didn't neither, but all at once it popped onto me that it was -Friday." - -"Blame it, a body can't be too careful, Huck. We might 'a' got into an -awful scrape, tackling such a thing on a Friday." - -"MIGHT! Better say we WOULD! There's some lucky days, maybe, but -Friday ain't." - -"Any fool knows that. I don't reckon YOU was the first that found it -out, Huck." - -"Well, I never said I was, did I? And Friday ain't all, neither. I had -a rotten bad dream last night--dreampt about rats." - -"No! Sure sign of trouble. Did they fight?" - -"No." - -"Well, that's good, Huck. When they don't fight it's only a sign that -there's trouble around, you know. All we got to do is to look mighty -sharp and keep out of it. We'll drop this thing for to-day, and play. -Do you know Robin Hood, Huck?" - -"No. Who's Robin Hood?" - -"Why, he was one of the greatest men that was ever in England--and the -best. He was a robber." - -"Cracky, I wisht I was. Who did he rob?" - -"Only sheriffs and bishops and rich people and kings, and such like. -But he never bothered the poor. He loved 'em. He always divided up with -'em perfectly square." - -"Well, he must 'a' been a brick." - -"I bet you he was, Huck. Oh, he was the noblest man that ever was. -They ain't any such men now, I can tell you. He could lick any man in -England, with one hand tied behind him; and he could take his yew bow -and plug a ten-cent piece every time, a mile and a half." - -"What's a YEW bow?" - -"I don't know. It's some kind of a bow, of course. And if he hit that -dime only on the edge he would set down and cry--and curse. But we'll -play Robin Hood--it's nobby fun. I'll learn you." - -"I'm agreed." - -So they played Robin Hood all the afternoon, now and then casting a -yearning eye down upon the haunted house and passing a remark about the -morrow's prospects and possibilities there. As the sun began to sink -into the west they took their way homeward athwart the long shadows of -the trees and soon were buried from sight in the forests of Cardiff -Hill. - -On Saturday, shortly after noon, the boys were at the dead tree again. -They had a smoke and a chat in the shade, and then dug a little in -their last hole, not with great hope, but merely because Tom said there -were so many cases where people had given up a treasure after getting -down within six inches of it, and then somebody else had come along and -turned it up with a single thrust of a shovel. The thing failed this -time, however, so the boys shouldered their tools and went away feeling -that they had not trifled with fortune, but had fulfilled all the -requirements that belong to the business of treasure-hunting. - -When they reached the haunted house there was something so weird and -grisly about the dead silence that reigned there under the baking sun, -and something so depressing about the loneliness and desolation of the -place, that they were afraid, for a moment, to venture in. Then they -crept to the door and took a trembling peep. They saw a weed-grown, -floorless room, unplastered, an ancient fireplace, vacant windows, a -ruinous staircase; and here, there, and everywhere hung ragged and -abandoned cobwebs. They presently entered, softly, with quickened -pulses, talking in whispers, ears alert to catch the slightest sound, -and muscles tense and ready for instant retreat. - -In a little while familiarity modified their fears and they gave the -place a critical and interested examination, rather admiring their own -boldness, and wondering at it, too. Next they wanted to look up-stairs. -This was something like cutting off retreat, but they got to daring -each other, and of course there could be but one result--they threw -their tools into a corner and made the ascent. Up there were the same -signs of decay. In one corner they found a closet that promised -mystery, but the promise was a fraud--there was nothing in it. Their -courage was up now and well in hand. They were about to go down and -begin work when-- - -"Sh!" said Tom. - -"What is it?" whispered Huck, blanching with fright. - -"Sh!... There!... Hear it?" - -"Yes!... Oh, my! Let's run!" - -"Keep still! Don't you budge! They're coming right toward the door." - -The boys stretched themselves upon the floor with their eyes to -knot-holes in the planking, and lay waiting, in a misery of fear. - -"They've stopped.... No--coming.... Here they are. Don't whisper -another word, Huck. My goodness, I wish I was out of this!" - -Two men entered. Each boy said to himself: "There's the old deaf and -dumb Spaniard that's been about town once or twice lately--never saw -t'other man before." - -"T'other" was a ragged, unkempt creature, with nothing very pleasant -in his face. The Spaniard was wrapped in a serape; he had bushy white -whiskers; long white hair flowed from under his sombrero, and he wore -green goggles. When they came in, "t'other" was talking in a low voice; -they sat down on the ground, facing the door, with their backs to the -wall, and the speaker continued his remarks. His manner became less -guarded and his words more distinct as he proceeded: - -"No," said he, "I've thought it all over, and I don't like it. It's -dangerous." - -"Dangerous!" grunted the "deaf and dumb" Spaniard--to the vast -surprise of the boys. "Milksop!" - -This voice made the boys gasp and quake. It was Injun Joe's! There was -silence for some time. Then Joe said: - -"What's any more dangerous than that job up yonder--but nothing's come -of it." - -"That's different. Away up the river so, and not another house about. -'Twon't ever be known that we tried, anyway, long as we didn't succeed." - -"Well, what's more dangerous than coming here in the daytime!--anybody -would suspicion us that saw us." - -"I know that. But there warn't any other place as handy after that -fool of a job. I want to quit this shanty. I wanted to yesterday, only -it warn't any use trying to stir out of here, with those infernal boys -playing over there on the hill right in full view." - -"Those infernal boys" quaked again under the inspiration of this -remark, and thought how lucky it was that they had remembered it was -Friday and concluded to wait a day. They wished in their hearts they -had waited a year. - -The two men got out some food and made a luncheon. After a long and -thoughtful silence, Injun Joe said: - -"Look here, lad--you go back up the river where you belong. Wait there -till you hear from me. I'll take the chances on dropping into this town -just once more, for a look. We'll do that 'dangerous' job after I've -spied around a little and think things look well for it. Then for -Texas! We'll leg it together!" - -This was satisfactory. Both men presently fell to yawning, and Injun -Joe said: - -"I'm dead for sleep! It's your turn to watch." - -He curled down in the weeds and soon began to snore. His comrade -stirred him once or twice and he became quiet. Presently the watcher -began to nod; his head drooped lower and lower, both men began to snore -now. - -The boys drew a long, grateful breath. Tom whispered: - -"Now's our chance--come!" - -Huck said: - -"I can't--I'd die if they was to wake." - -Tom urged--Huck held back. At last Tom rose slowly and softly, and -started alone. But the first step he made wrung such a hideous creak -from the crazy floor that he sank down almost dead with fright. He -never made a second attempt. The boys lay there counting the dragging -moments till it seemed to them that time must be done and eternity -growing gray; and then they were grateful to note that at last the sun -was setting. - -Now one snore ceased. Injun Joe sat up, stared around--smiled grimly -upon his comrade, whose head was drooping upon his knees--stirred him -up with his foot and said: - -"Here! YOU'RE a watchman, ain't you! All right, though--nothing's -happened." - -"My! have I been asleep?" - -"Oh, partly, partly. Nearly time for us to be moving, pard. What'll we -do with what little swag we've got left?" - -"I don't know--leave it here as we've always done, I reckon. No use to -take it away till we start south. Six hundred and fifty in silver's -something to carry." - -"Well--all right--it won't matter to come here once more." - -"No--but I'd say come in the night as we used to do--it's better." - -"Yes: but look here; it may be a good while before I get the right -chance at that job; accidents might happen; 'tain't in such a very good -place; we'll just regularly bury it--and bury it deep." - -"Good idea," said the comrade, who walked across the room, knelt down, -raised one of the rearward hearth-stones and took out a bag that -jingled pleasantly. He subtracted from it twenty or thirty dollars for -himself and as much for Injun Joe, and passed the bag to the latter, -who was on his knees in the corner, now, digging with his bowie-knife. - -The boys forgot all their fears, all their miseries in an instant. -With gloating eyes they watched every movement. Luck!--the splendor of -it was beyond all imagination! Six hundred dollars was money enough to -make half a dozen boys rich! Here was treasure-hunting under the -happiest auspices--there would not be any bothersome uncertainty as to -where to dig. They nudged each other every moment--eloquent nudges and -easily understood, for they simply meant--"Oh, but ain't you glad NOW -we're here!" - -Joe's knife struck upon something. - -"Hello!" said he. - -"What is it?" said his comrade. - -"Half-rotten plank--no, it's a box, I believe. Here--bear a hand and -we'll see what it's here for. Never mind, I've broke a hole." - -He reached his hand in and drew it out-- - -"Man, it's money!" - -The two men examined the handful of coins. They were gold. The boys -above were as excited as themselves, and as delighted. - -Joe's comrade said: - -"We'll make quick work of this. There's an old rusty pick over amongst -the weeds in the corner the other side of the fireplace--I saw it a -minute ago." - -He ran and brought the boys' pick and shovel. Injun Joe took the pick, -looked it over critically, shook his head, muttered something to -himself, and then began to use it. The box was soon unearthed. It was -not very large; it was iron bound and had been very strong before the -slow years had injured it. The men contemplated the treasure awhile in -blissful silence. - -"Pard, there's thousands of dollars here," said Injun Joe. - -"'Twas always said that Murrel's gang used to be around here one -summer," the stranger observed. - -"I know it," said Injun Joe; "and this looks like it, I should say." - -"Now you won't need to do that job." - -The half-breed frowned. Said he: - -"You don't know me. Least you don't know all about that thing. 'Tain't -robbery altogether--it's REVENGE!" and a wicked light flamed in his -eyes. "I'll need your help in it. When it's finished--then Texas. Go -home to your Nance and your kids, and stand by till you hear from me." - -"Well--if you say so; what'll we do with this--bury it again?" - -"Yes. [Ravishing delight overhead.] NO! by the great Sachem, no! -[Profound distress overhead.] I'd nearly forgot. That pick had fresh -earth on it! [The boys were sick with terror in a moment.] What -business has a pick and a shovel here? What business with fresh earth -on them? Who brought them here--and where are they gone? Have you heard -anybody?--seen anybody? What! bury it again and leave them to come and -see the ground disturbed? Not exactly--not exactly. We'll take it to my -den." - -"Why, of course! Might have thought of that before. You mean Number -One?" - -"No--Number Two--under the cross. The other place is bad--too common." - -"All right. It's nearly dark enough to start." - -Injun Joe got up and went about from window to window cautiously -peeping out. Presently he said: - -"Who could have brought those tools here? Do you reckon they can be -up-stairs?" - -The boys' breath forsook them. Injun Joe put his hand on his knife, -halted a moment, undecided, and then turned toward the stairway. The -boys thought of the closet, but their strength was gone. The steps came -creaking up the stairs--the intolerable distress of the situation woke -the stricken resolution of the lads--they were about to spring for the -closet, when there was a crash of rotten timbers and Injun Joe landed -on the ground amid the debris of the ruined stairway. He gathered -himself up cursing, and his comrade said: - -"Now what's the use of all that? If it's anybody, and they're up -there, let them STAY there--who cares? If they want to jump down, now, -and get into trouble, who objects? It will be dark in fifteen minutes ---and then let them follow us if they want to. I'm willing. In my -opinion, whoever hove those things in here caught a sight of us and -took us for ghosts or devils or something. I'll bet they're running -yet." - -Joe grumbled awhile; then he agreed with his friend that what daylight -was left ought to be economized in getting things ready for leaving. -Shortly afterward they slipped out of the house in the deepening -twilight, and moved toward the river with their precious box. - -Tom and Huck rose up, weak but vastly relieved, and stared after them -through the chinks between the logs of the house. Follow? Not they. -They were content to reach ground again without broken necks, and take -the townward track over the hill. They did not talk much. They were too -much absorbed in hating themselves--hating the ill luck that made them -take the spade and the pick there. But for that, Injun Joe never would -have suspected. He would have hidden the silver with the gold to wait -there till his "revenge" was satisfied, and then he would have had the -misfortune to find that money turn up missing. Bitter, bitter luck that -the tools were ever brought there! - -They resolved to keep a lookout for that Spaniard when he should come -to town spying out for chances to do his revengeful job, and follow him -to "Number Two," wherever that might be. Then a ghastly thought -occurred to Tom. - -"Revenge? What if he means US, Huck!" - -"Oh, don't!" said Huck, nearly fainting. - -They talked it all over, and as they entered town they agreed to -believe that he might possibly mean somebody else--at least that he -might at least mean nobody but Tom, since only Tom had testified. - -Very, very small comfort it was to Tom to be alone in danger! Company -would be a palpable improvement, he thought. - - - -CHAPTER XXVII - -THE adventure of the day mightily tormented Tom's dreams that night. -Four times he had his hands on that rich treasure and four times it -wasted to nothingness in his fingers as sleep forsook him and -wakefulness brought back the hard reality of his misfortune. As he lay -in the early morning recalling the incidents of his great adventure, he -noticed that they seemed curiously subdued and far away--somewhat as if -they had happened in another world, or in a time long gone by. Then it -occurred to him that the great adventure itself must be a dream! There -was one very strong argument in favor of this idea--namely, that the -quantity of coin he had seen was too vast to be real. He had never seen -as much as fifty dollars in one mass before, and he was like all boys -of his age and station in life, in that he imagined that all references -to "hundreds" and "thousands" were mere fanciful forms of speech, and -that no such sums really existed in the world. He never had supposed -for a moment that so large a sum as a hundred dollars was to be found -in actual money in any one's possession. If his notions of hidden -treasure had been analyzed, they would have been found to consist of a -handful of real dimes and a bushel of vague, splendid, ungraspable -dollars. - -But the incidents of his adventure grew sensibly sharper and clearer -under the attrition of thinking them over, and so he presently found -himself leaning to the impression that the thing might not have been a -dream, after all. This uncertainty must be swept away. He would snatch -a hurried breakfast and go and find Huck. Huck was sitting on the -gunwale of a flatboat, listlessly dangling his feet in the water and -looking very melancholy. Tom concluded to let Huck lead up to the -subject. If he did not do it, then the adventure would be proved to -have been only a dream. - -"Hello, Huck!" - -"Hello, yourself." - -Silence, for a minute. - -"Tom, if we'd 'a' left the blame tools at the dead tree, we'd 'a' got -the money. Oh, ain't it awful!" - -"'Tain't a dream, then, 'tain't a dream! Somehow I most wish it was. -Dog'd if I don't, Huck." - -"What ain't a dream?" - -"Oh, that thing yesterday. I been half thinking it was." - -"Dream! If them stairs hadn't broke down you'd 'a' seen how much dream -it was! I've had dreams enough all night--with that patch-eyed Spanish -devil going for me all through 'em--rot him!" - -"No, not rot him. FIND him! Track the money!" - -"Tom, we'll never find him. A feller don't have only one chance for -such a pile--and that one's lost. I'd feel mighty shaky if I was to see -him, anyway." - -"Well, so'd I; but I'd like to see him, anyway--and track him out--to -his Number Two." - -"Number Two--yes, that's it. I been thinking 'bout that. But I can't -make nothing out of it. What do you reckon it is?" - -"I dono. It's too deep. Say, Huck--maybe it's the number of a house!" - -"Goody!... No, Tom, that ain't it. If it is, it ain't in this -one-horse town. They ain't no numbers here." - -"Well, that's so. Lemme think a minute. Here--it's the number of a -room--in a tavern, you know!" - -"Oh, that's the trick! They ain't only two taverns. We can find out -quick." - -"You stay here, Huck, till I come." - -Tom was off at once. He did not care to have Huck's company in public -places. He was gone half an hour. He found that in the best tavern, No. -2 had long been occupied by a young lawyer, and was still so occupied. -In the less ostentatious house, No. 2 was a mystery. The -tavern-keeper's young son said it was kept locked all the time, and he -never saw anybody go into it or come out of it except at night; he did -not know any particular reason for this state of things; had had some -little curiosity, but it was rather feeble; had made the most of the -mystery by entertaining himself with the idea that that room was -"ha'nted"; had noticed that there was a light in there the night before. - -"That's what I've found out, Huck. I reckon that's the very No. 2 -we're after." - -"I reckon it is, Tom. Now what you going to do?" - -"Lemme think." - -Tom thought a long time. Then he said: - -"I'll tell you. The back door of that No. 2 is the door that comes out -into that little close alley between the tavern and the old rattle trap -of a brick store. Now you get hold of all the door-keys you can find, -and I'll nip all of auntie's, and the first dark night we'll go there -and try 'em. And mind you, keep a lookout for Injun Joe, because he -said he was going to drop into town and spy around once more for a -chance to get his revenge. If you see him, you just follow him; and if -he don't go to that No. 2, that ain't the place." - -"Lordy, I don't want to foller him by myself!" - -"Why, it'll be night, sure. He mightn't ever see you--and if he did, -maybe he'd never think anything." - -"Well, if it's pretty dark I reckon I'll track him. I dono--I dono. -I'll try." - -"You bet I'll follow him, if it's dark, Huck. Why, he might 'a' found -out he couldn't get his revenge, and be going right after that money." - -"It's so, Tom, it's so. I'll foller him; I will, by jingoes!" - -"Now you're TALKING! Don't you ever weaken, Huck, and I won't." - - - -CHAPTER XXVIII - -THAT night Tom and Huck were ready for their adventure. They hung -about the neighborhood of the tavern until after nine, one watching the -alley at a distance and the other the tavern door. Nobody entered the -alley or left it; nobody resembling the Spaniard entered or left the -tavern door. The night promised to be a fair one; so Tom went home with -the understanding that if a considerable degree of darkness came on, -Huck was to come and "maow," whereupon he would slip out and try the -keys. But the night remained clear, and Huck closed his watch and -retired to bed in an empty sugar hogshead about twelve. - -Tuesday the boys had the same ill luck. Also Wednesday. But Thursday -night promised better. Tom slipped out in good season with his aunt's -old tin lantern, and a large towel to blindfold it with. He hid the -lantern in Huck's sugar hogshead and the watch began. An hour before -midnight the tavern closed up and its lights (the only ones -thereabouts) were put out. No Spaniard had been seen. Nobody had -entered or left the alley. Everything was auspicious. The blackness of -darkness reigned, the perfect stillness was interrupted only by -occasional mutterings of distant thunder. - -Tom got his lantern, lit it in the hogshead, wrapped it closely in the -towel, and the two adventurers crept in the gloom toward the tavern. -Huck stood sentry and Tom felt his way into the alley. Then there was a -season of waiting anxiety that weighed upon Huck's spirits like a -mountain. He began to wish he could see a flash from the lantern--it -would frighten him, but it would at least tell him that Tom was alive -yet. It seemed hours since Tom had disappeared. Surely he must have -fainted; maybe he was dead; maybe his heart had burst under terror and -excitement. In his uneasiness Huck found himself drawing closer and -closer to the alley; fearing all sorts of dreadful things, and -momentarily expecting some catastrophe to happen that would take away -his breath. There was not much to take away, for he seemed only able to -inhale it by thimblefuls, and his heart would soon wear itself out, the -way it was beating. Suddenly there was a flash of light and Tom came -tearing by him: "Run!" said he; "run, for your life!" - -He needn't have repeated it; once was enough; Huck was making thirty -or forty miles an hour before the repetition was uttered. The boys -never stopped till they reached the shed of a deserted slaughter-house -at the lower end of the village. Just as they got within its shelter -the storm burst and the rain poured down. As soon as Tom got his breath -he said: - -"Huck, it was awful! I tried two of the keys, just as soft as I could; -but they seemed to make such a power of racket that I couldn't hardly -get my breath I was so scared. They wouldn't turn in the lock, either. -Well, without noticing what I was doing, I took hold of the knob, and -open comes the door! It warn't locked! I hopped in, and shook off the -towel, and, GREAT CAESAR'S GHOST!" - -"What!--what'd you see, Tom?" - -"Huck, I most stepped onto Injun Joe's hand!" - -"No!" - -"Yes! He was lying there, sound asleep on the floor, with his old -patch on his eye and his arms spread out." - -"Lordy, what did you do? Did he wake up?" - -"No, never budged. Drunk, I reckon. I just grabbed that towel and -started!" - -"I'd never 'a' thought of the towel, I bet!" - -"Well, I would. My aunt would make me mighty sick if I lost it." - -"Say, Tom, did you see that box?" - -"Huck, I didn't wait to look around. I didn't see the box, I didn't -see the cross. I didn't see anything but a bottle and a tin cup on the -floor by Injun Joe; yes, I saw two barrels and lots more bottles in the -room. Don't you see, now, what's the matter with that ha'nted room?" - -"How?" - -"Why, it's ha'nted with whiskey! Maybe ALL the Temperance Taverns have -got a ha'nted room, hey, Huck?" - -"Well, I reckon maybe that's so. Who'd 'a' thought such a thing? But -say, Tom, now's a mighty good time to get that box, if Injun Joe's -drunk." - -"It is, that! You try it!" - -Huck shuddered. - -"Well, no--I reckon not." - -"And I reckon not, Huck. Only one bottle alongside of Injun Joe ain't -enough. If there'd been three, he'd be drunk enough and I'd do it." - -There was a long pause for reflection, and then Tom said: - -"Lookyhere, Huck, less not try that thing any more till we know Injun -Joe's not in there. It's too scary. Now, if we watch every night, we'll -be dead sure to see him go out, some time or other, and then we'll -snatch that box quicker'n lightning." - -"Well, I'm agreed. I'll watch the whole night long, and I'll do it -every night, too, if you'll do the other part of the job." - -"All right, I will. All you got to do is to trot up Hooper Street a -block and maow--and if I'm asleep, you throw some gravel at the window -and that'll fetch me." - -"Agreed, and good as wheat!" - -"Now, Huck, the storm's over, and I'll go home. It'll begin to be -daylight in a couple of hours. You go back and watch that long, will -you?" - -"I said I would, Tom, and I will. I'll ha'nt that tavern every night -for a year! I'll sleep all day and I'll stand watch all night." - -"That's all right. Now, where you going to sleep?" - -"In Ben Rogers' hayloft. He lets me, and so does his pap's nigger man, -Uncle Jake. I tote water for Uncle Jake whenever he wants me to, and -any time I ask him he gives me a little something to eat if he can -spare it. That's a mighty good nigger, Tom. He likes me, becuz I don't -ever act as if I was above him. Sometime I've set right down and eat -WITH him. But you needn't tell that. A body's got to do things when -he's awful hungry he wouldn't want to do as a steady thing." - -"Well, if I don't want you in the daytime, I'll let you sleep. I won't -come bothering around. Any time you see something's up, in the night, -just skip right around and maow." - - - -CHAPTER XXIX - -THE first thing Tom heard on Friday morning was a glad piece of news ---Judge Thatcher's family had come back to town the night before. Both -Injun Joe and the treasure sunk into secondary importance for a moment, -and Becky took the chief place in the boy's interest. He saw her and -they had an exhausting good time playing "hi-spy" and "gully-keeper" -with a crowd of their school-mates. The day was completed and crowned -in a peculiarly satisfactory way: Becky teased her mother to appoint -the next day for the long-promised and long-delayed picnic, and she -consented. The child's delight was boundless; and Tom's not more -moderate. The invitations were sent out before sunset, and straightway -the young folks of the village were thrown into a fever of preparation -and pleasurable anticipation. Tom's excitement enabled him to keep -awake until a pretty late hour, and he had good hopes of hearing Huck's -"maow," and of having his treasure to astonish Becky and the picnickers -with, next day; but he was disappointed. No signal came that night. - -Morning came, eventually, and by ten or eleven o'clock a giddy and -rollicking company were gathered at Judge Thatcher's, and everything -was ready for a start. It was not the custom for elderly people to mar -the picnics with their presence. The children were considered safe -enough under the wings of a few young ladies of eighteen and a few -young gentlemen of twenty-three or thereabouts. The old steam ferryboat -was chartered for the occasion; presently the gay throng filed up the -main street laden with provision-baskets. Sid was sick and had to miss -the fun; Mary remained at home to entertain him. The last thing Mrs. -Thatcher said to Becky, was: - -"You'll not get back till late. Perhaps you'd better stay all night -with some of the girls that live near the ferry-landing, child." - -"Then I'll stay with Susy Harper, mamma." - -"Very well. And mind and behave yourself and don't be any trouble." - -Presently, as they tripped along, Tom said to Becky: - -"Say--I'll tell you what we'll do. 'Stead of going to Joe Harper's -we'll climb right up the hill and stop at the Widow Douglas'. She'll -have ice-cream! She has it most every day--dead loads of it. And she'll -be awful glad to have us." - -"Oh, that will be fun!" - -Then Becky reflected a moment and said: - -"But what will mamma say?" - -"How'll she ever know?" - -The girl turned the idea over in her mind, and said reluctantly: - -"I reckon it's wrong--but--" - -"But shucks! Your mother won't know, and so what's the harm? All she -wants is that you'll be safe; and I bet you she'd 'a' said go there if -she'd 'a' thought of it. I know she would!" - -The Widow Douglas' splendid hospitality was a tempting bait. It and -Tom's persuasions presently carried the day. So it was decided to say -nothing anybody about the night's programme. Presently it occurred to -Tom that maybe Huck might come this very night and give the signal. The -thought took a deal of the spirit out of his anticipations. Still he -could not bear to give up the fun at Widow Douglas'. And why should he -give it up, he reasoned--the signal did not come the night before, so -why should it be any more likely to come to-night? The sure fun of the -evening outweighed the uncertain treasure; and, boy-like, he determined -to yield to the stronger inclination and not allow himself to think of -the box of money another time that day. - -Three miles below town the ferryboat stopped at the mouth of a woody -hollow and tied up. The crowd swarmed ashore and soon the forest -distances and craggy heights echoed far and near with shoutings and -laughter. All the different ways of getting hot and tired were gone -through with, and by-and-by the rovers straggled back to camp fortified -with responsible appetites, and then the destruction of the good things -began. After the feast there was a refreshing season of rest and chat -in the shade of spreading oaks. By-and-by somebody shouted: - -"Who's ready for the cave?" - -Everybody was. Bundles of candles were procured, and straightway there -was a general scamper up the hill. The mouth of the cave was up the -hillside--an opening shaped like a letter A. Its massive oaken door -stood unbarred. Within was a small chamber, chilly as an ice-house, and -walled by Nature with solid limestone that was dewy with a cold sweat. -It was romantic and mysterious to stand here in the deep gloom and look -out upon the green valley shining in the sun. But the impressiveness of -the situation quickly wore off, and the romping began again. The moment -a candle was lighted there was a general rush upon the owner of it; a -struggle and a gallant defence followed, but the candle was soon -knocked down or blown out, and then there was a glad clamor of laughter -and a new chase. But all things have an end. By-and-by the procession -went filing down the steep descent of the main avenue, the flickering -rank of lights dimly revealing the lofty walls of rock almost to their -point of junction sixty feet overhead. This main avenue was not more -than eight or ten feet wide. Every few steps other lofty and still -narrower crevices branched from it on either hand--for McDougal's cave -was but a vast labyrinth of crooked aisles that ran into each other and -out again and led nowhere. It was said that one might wander days and -nights together through its intricate tangle of rifts and chasms, and -never find the end of the cave; and that he might go down, and down, -and still down, into the earth, and it was just the same--labyrinth -under labyrinth, and no end to any of them. No man "knew" the cave. -That was an impossible thing. Most of the young men knew a portion of -it, and it was not customary to venture much beyond this known portion. -Tom Sawyer knew as much of the cave as any one. - -The procession moved along the main avenue some three-quarters of a -mile, and then groups and couples began to slip aside into branch -avenues, fly along the dismal corridors, and take each other by -surprise at points where the corridors joined again. Parties were able -to elude each other for the space of half an hour without going beyond -the "known" ground. - -By-and-by, one group after another came straggling back to the mouth -of the cave, panting, hilarious, smeared from head to foot with tallow -drippings, daubed with clay, and entirely delighted with the success of -the day. Then they were astonished to find that they had been taking no -note of time and that night was about at hand. The clanging bell had -been calling for half an hour. However, this sort of close to the day's -adventures was romantic and therefore satisfactory. When the ferryboat -with her wild freight pushed into the stream, nobody cared sixpence for -the wasted time but the captain of the craft. - -Huck was already upon his watch when the ferryboat's lights went -glinting past the wharf. He heard no noise on board, for the young -people were as subdued and still as people usually are who are nearly -tired to death. He wondered what boat it was, and why she did not stop -at the wharf--and then he dropped her out of his mind and put his -attention upon his business. The night was growing cloudy and dark. Ten -o'clock came, and the noise of vehicles ceased, scattered lights began -to wink out, all straggling foot-passengers disappeared, the village -betook itself to its slumbers and left the small watcher alone with the -silence and the ghosts. Eleven o'clock came, and the tavern lights were -put out; darkness everywhere, now. Huck waited what seemed a weary long -time, but nothing happened. His faith was weakening. Was there any use? -Was there really any use? Why not give it up and turn in? - -A noise fell upon his ear. He was all attention in an instant. The -alley door closed softly. He sprang to the corner of the brick store. -The next moment two men brushed by him, and one seemed to have -something under his arm. It must be that box! So they were going to -remove the treasure. Why call Tom now? It would be absurd--the men -would get away with the box and never be found again. No, he would -stick to their wake and follow them; he would trust to the darkness for -security from discovery. So communing with himself, Huck stepped out -and glided along behind the men, cat-like, with bare feet, allowing -them to keep just far enough ahead not to be invisible. - -They moved up the river street three blocks, then turned to the left -up a cross-street. They went straight ahead, then, until they came to -the path that led up Cardiff Hill; this they took. They passed by the -old Welshman's house, half-way up the hill, without hesitating, and -still climbed upward. Good, thought Huck, they will bury it in the old -quarry. But they never stopped at the quarry. They passed on, up the -summit. They plunged into the narrow path between the tall sumach -bushes, and were at once hidden in the gloom. Huck closed up and -shortened his distance, now, for they would never be able to see him. -He trotted along awhile; then slackened his pace, fearing he was -gaining too fast; moved on a piece, then stopped altogether; listened; -no sound; none, save that he seemed to hear the beating of his own -heart. The hooting of an owl came over the hill--ominous sound! But no -footsteps. Heavens, was everything lost! He was about to spring with -winged feet, when a man cleared his throat not four feet from him! -Huck's heart shot into his throat, but he swallowed it again; and then -he stood there shaking as if a dozen agues had taken charge of him at -once, and so weak that he thought he must surely fall to the ground. He -knew where he was. He knew he was within five steps of the stile -leading into Widow Douglas' grounds. Very well, he thought, let them -bury it there; it won't be hard to find. - -Now there was a voice--a very low voice--Injun Joe's: - -"Damn her, maybe she's got company--there's lights, late as it is." - -"I can't see any." - -This was that stranger's voice--the stranger of the haunted house. A -deadly chill went to Huck's heart--this, then, was the "revenge" job! -His thought was, to fly. Then he remembered that the Widow Douglas had -been kind to him more than once, and maybe these men were going to -murder her. He wished he dared venture to warn her; but he knew he -didn't dare--they might come and catch him. He thought all this and -more in the moment that elapsed between the stranger's remark and Injun -Joe's next--which was-- - -"Because the bush is in your way. Now--this way--now you see, don't -you?" - -"Yes. Well, there IS company there, I reckon. Better give it up." - -"Give it up, and I just leaving this country forever! Give it up and -maybe never have another chance. I tell you again, as I've told you -before, I don't care for her swag--you may have it. But her husband was -rough on me--many times he was rough on me--and mainly he was the -justice of the peace that jugged me for a vagrant. And that ain't all. -It ain't a millionth part of it! He had me HORSEWHIPPED!--horsewhipped -in front of the jail, like a nigger!--with all the town looking on! -HORSEWHIPPED!--do you understand? He took advantage of me and died. But -I'll take it out of HER." - -"Oh, don't kill her! Don't do that!" - -"Kill? Who said anything about killing? I would kill HIM if he was -here; but not her. When you want to get revenge on a woman you don't -kill her--bosh! you go for her looks. You slit her nostrils--you notch -her ears like a sow!" - -"By God, that's--" - -"Keep your opinion to yourself! It will be safest for you. I'll tie -her to the bed. If she bleeds to death, is that my fault? I'll not cry, -if she does. My friend, you'll help me in this thing--for MY sake ---that's why you're here--I mightn't be able alone. If you flinch, I'll -kill you. Do you understand that? And if I have to kill you, I'll kill -her--and then I reckon nobody'll ever know much about who done this -business." - -"Well, if it's got to be done, let's get at it. The quicker the -better--I'm all in a shiver." - -"Do it NOW? And company there? Look here--I'll get suspicious of you, -first thing you know. No--we'll wait till the lights are out--there's -no hurry." - -Huck felt that a silence was going to ensue--a thing still more awful -than any amount of murderous talk; so he held his breath and stepped -gingerly back; planted his foot carefully and firmly, after balancing, -one-legged, in a precarious way and almost toppling over, first on one -side and then on the other. He took another step back, with the same -elaboration and the same risks; then another and another, and--a twig -snapped under his foot! His breath stopped and he listened. There was -no sound--the stillness was perfect. His gratitude was measureless. Now -he turned in his tracks, between the walls of sumach bushes--turned -himself as carefully as if he were a ship--and then stepped quickly but -cautiously along. When he emerged at the quarry he felt secure, and so -he picked up his nimble heels and flew. Down, down he sped, till he -reached the Welshman's. He banged at the door, and presently the heads -of the old man and his two stalwart sons were thrust from windows. - -"What's the row there? Who's banging? What do you want?" - -"Let me in--quick! I'll tell everything." - -"Why, who are you?" - -"Huckleberry Finn--quick, let me in!" - -"Huckleberry Finn, indeed! It ain't a name to open many doors, I -judge! But let him in, lads, and let's see what's the trouble." - -"Please don't ever tell I told you," were Huck's first words when he -got in. "Please don't--I'd be killed, sure--but the widow's been good -friends to me sometimes, and I want to tell--I WILL tell if you'll -promise you won't ever say it was me." - -"By George, he HAS got something to tell, or he wouldn't act so!" -exclaimed the old man; "out with it and nobody here'll ever tell, lad." - -Three minutes later the old man and his sons, well armed, were up the -hill, and just entering the sumach path on tiptoe, their weapons in -their hands. Huck accompanied them no further. He hid behind a great -bowlder and fell to listening. There was a lagging, anxious silence, -and then all of a sudden there was an explosion of firearms and a cry. - -Huck waited for no particulars. He sprang away and sped down the hill -as fast as his legs could carry him. - - - -CHAPTER XXX - -AS the earliest suspicion of dawn appeared on Sunday morning, Huck -came groping up the hill and rapped gently at the old Welshman's door. -The inmates were asleep, but it was a sleep that was set on a -hair-trigger, on account of the exciting episode of the night. A call -came from a window: - -"Who's there!" - -Huck's scared voice answered in a low tone: - -"Please let me in! It's only Huck Finn!" - -"It's a name that can open this door night or day, lad!--and welcome!" - -These were strange words to the vagabond boy's ears, and the -pleasantest he had ever heard. He could not recollect that the closing -word had ever been applied in his case before. The door was quickly -unlocked, and he entered. Huck was given a seat and the old man and his -brace of tall sons speedily dressed themselves. - -"Now, my boy, I hope you're good and hungry, because breakfast will be -ready as soon as the sun's up, and we'll have a piping hot one, too ---make yourself easy about that! I and the boys hoped you'd turn up and -stop here last night." - -"I was awful scared," said Huck, "and I run. I took out when the -pistols went off, and I didn't stop for three mile. I've come now becuz -I wanted to know about it, you know; and I come before daylight becuz I -didn't want to run across them devils, even if they was dead." - -"Well, poor chap, you do look as if you'd had a hard night of it--but -there's a bed here for you when you've had your breakfast. No, they -ain't dead, lad--we are sorry enough for that. You see we knew right -where to put our hands on them, by your description; so we crept along -on tiptoe till we got within fifteen feet of them--dark as a cellar -that sumach path was--and just then I found I was going to sneeze. It -was the meanest kind of luck! I tried to keep it back, but no use ---'twas bound to come, and it did come! I was in the lead with my pistol -raised, and when the sneeze started those scoundrels a-rustling to get -out of the path, I sung out, 'Fire boys!' and blazed away at the place -where the rustling was. So did the boys. But they were off in a jiffy, -those villains, and we after them, down through the woods. I judge we -never touched them. They fired a shot apiece as they started, but their -bullets whizzed by and didn't do us any harm. As soon as we lost the -sound of their feet we quit chasing, and went down and stirred up the -constables. They got a posse together, and went off to guard the river -bank, and as soon as it is light the sheriff and a gang are going to -beat up the woods. My boys will be with them presently. I wish we had -some sort of description of those rascals--'twould help a good deal. -But you couldn't see what they were like, in the dark, lad, I suppose?" - -"Oh yes; I saw them down-town and follered them." - -"Splendid! Describe them--describe them, my boy!" - -"One's the old deaf and dumb Spaniard that's ben around here once or -twice, and t'other's a mean-looking, ragged--" - -"That's enough, lad, we know the men! Happened on them in the woods -back of the widow's one day, and they slunk away. Off with you, boys, -and tell the sheriff--get your breakfast to-morrow morning!" - -The Welshman's sons departed at once. As they were leaving the room -Huck sprang up and exclaimed: - -"Oh, please don't tell ANYbody it was me that blowed on them! Oh, -please!" - -"All right if you say it, Huck, but you ought to have the credit of -what you did." - -"Oh no, no! Please don't tell!" - -When the young men were gone, the old Welshman said: - -"They won't tell--and I won't. But why don't you want it known?" - -Huck would not explain, further than to say that he already knew too -much about one of those men and would not have the man know that he -knew anything against him for the whole world--he would be killed for -knowing it, sure. - -The old man promised secrecy once more, and said: - -"How did you come to follow these fellows, lad? Were they looking -suspicious?" - -Huck was silent while he framed a duly cautious reply. Then he said: - -"Well, you see, I'm a kind of a hard lot,--least everybody says so, -and I don't see nothing agin it--and sometimes I can't sleep much, on -account of thinking about it and sort of trying to strike out a new way -of doing. That was the way of it last night. I couldn't sleep, and so I -come along up-street 'bout midnight, a-turning it all over, and when I -got to that old shackly brick store by the Temperance Tavern, I backed -up agin the wall to have another think. Well, just then along comes -these two chaps slipping along close by me, with something under their -arm, and I reckoned they'd stole it. One was a-smoking, and t'other one -wanted a light; so they stopped right before me and the cigars lit up -their faces and I see that the big one was the deaf and dumb Spaniard, -by his white whiskers and the patch on his eye, and t'other one was a -rusty, ragged-looking devil." - -"Could you see the rags by the light of the cigars?" - -This staggered Huck for a moment. Then he said: - -"Well, I don't know--but somehow it seems as if I did." - -"Then they went on, and you--" - -"Follered 'em--yes. That was it. I wanted to see what was up--they -sneaked along so. I dogged 'em to the widder's stile, and stood in the -dark and heard the ragged one beg for the widder, and the Spaniard -swear he'd spile her looks just as I told you and your two--" - -"What! The DEAF AND DUMB man said all that!" - -Huck had made another terrible mistake! He was trying his best to keep -the old man from getting the faintest hint of who the Spaniard might -be, and yet his tongue seemed determined to get him into trouble in -spite of all he could do. He made several efforts to creep out of his -scrape, but the old man's eye was upon him and he made blunder after -blunder. Presently the Welshman said: - -"My boy, don't be afraid of me. I wouldn't hurt a hair of your head -for all the world. No--I'd protect you--I'd protect you. This Spaniard -is not deaf and dumb; you've let that slip without intending it; you -can't cover that up now. You know something about that Spaniard that -you want to keep dark. Now trust me--tell me what it is, and trust me ---I won't betray you." - -Huck looked into the old man's honest eyes a moment, then bent over -and whispered in his ear: - -"'Tain't a Spaniard--it's Injun Joe!" - -The Welshman almost jumped out of his chair. In a moment he said: - -"It's all plain enough, now. When you talked about notching ears and -slitting noses I judged that that was your own embellishment, because -white men don't take that sort of revenge. But an Injun! That's a -different matter altogether." - -During breakfast the talk went on, and in the course of it the old man -said that the last thing which he and his sons had done, before going -to bed, was to get a lantern and examine the stile and its vicinity for -marks of blood. They found none, but captured a bulky bundle of-- - -"Of WHAT?" - -If the words had been lightning they could not have leaped with a more -stunning suddenness from Huck's blanched lips. His eyes were staring -wide, now, and his breath suspended--waiting for the answer. The -Welshman started--stared in return--three seconds--five seconds--ten ---then replied: - -"Of burglar's tools. Why, what's the MATTER with you?" - -Huck sank back, panting gently, but deeply, unutterably grateful. The -Welshman eyed him gravely, curiously--and presently said: - -"Yes, burglar's tools. That appears to relieve you a good deal. But -what did give you that turn? What were YOU expecting we'd found?" - -Huck was in a close place--the inquiring eye was upon him--he would -have given anything for material for a plausible answer--nothing -suggested itself--the inquiring eye was boring deeper and deeper--a -senseless reply offered--there was no time to weigh it, so at a venture -he uttered it--feebly: - -"Sunday-school books, maybe." - -Poor Huck was too distressed to smile, but the old man laughed loud -and joyously, shook up the details of his anatomy from head to foot, -and ended by saying that such a laugh was money in a-man's pocket, -because it cut down the doctor's bill like everything. Then he added: - -"Poor old chap, you're white and jaded--you ain't well a bit--no -wonder you're a little flighty and off your balance. But you'll come -out of it. Rest and sleep will fetch you out all right, I hope." - -Huck was irritated to think he had been such a goose and betrayed such -a suspicious excitement, for he had dropped the idea that the parcel -brought from the tavern was the treasure, as soon as he had heard the -talk at the widow's stile. He had only thought it was not the treasure, -however--he had not known that it wasn't--and so the suggestion of a -captured bundle was too much for his self-possession. But on the whole -he felt glad the little episode had happened, for now he knew beyond -all question that that bundle was not THE bundle, and so his mind was -at rest and exceedingly comfortable. In fact, everything seemed to be -drifting just in the right direction, now; the treasure must be still -in No. 2, the men would be captured and jailed that day, and he and Tom -could seize the gold that night without any trouble or any fear of -interruption. - -Just as breakfast was completed there was a knock at the door. Huck -jumped for a hiding-place, for he had no mind to be connected even -remotely with the late event. The Welshman admitted several ladies and -gentlemen, among them the Widow Douglas, and noticed that groups of -citizens were climbing up the hill--to stare at the stile. So the news -had spread. The Welshman had to tell the story of the night to the -visitors. The widow's gratitude for her preservation was outspoken. - -"Don't say a word about it, madam. There's another that you're more -beholden to than you are to me and my boys, maybe, but he don't allow -me to tell his name. We wouldn't have been there but for him." - -Of course this excited a curiosity so vast that it almost belittled -the main matter--but the Welshman allowed it to eat into the vitals of -his visitors, and through them be transmitted to the whole town, for he -refused to part with his secret. When all else had been learned, the -widow said: - -"I went to sleep reading in bed and slept straight through all that -noise. Why didn't you come and wake me?" - -"We judged it warn't worth while. Those fellows warn't likely to come -again--they hadn't any tools left to work with, and what was the use of -waking you up and scaring you to death? My three negro men stood guard -at your house all the rest of the night. They've just come back." - -More visitors came, and the story had to be told and retold for a -couple of hours more. - -There was no Sabbath-school during day-school vacation, but everybody -was early at church. The stirring event was well canvassed. News came -that not a sign of the two villains had been yet discovered. When the -sermon was finished, Judge Thatcher's wife dropped alongside of Mrs. -Harper as she moved down the aisle with the crowd and said: - -"Is my Becky going to sleep all day? I just expected she would be -tired to death." - -"Your Becky?" - -"Yes," with a startled look--"didn't she stay with you last night?" - -"Why, no." - -Mrs. Thatcher turned pale, and sank into a pew, just as Aunt Polly, -talking briskly with a friend, passed by. Aunt Polly said: - -"Good-morning, Mrs. Thatcher. Good-morning, Mrs. Harper. I've got a -boy that's turned up missing. I reckon my Tom stayed at your house last -night--one of you. And now he's afraid to come to church. I've got to -settle with him." - -Mrs. Thatcher shook her head feebly and turned paler than ever. - -"He didn't stay with us," said Mrs. Harper, beginning to look uneasy. -A marked anxiety came into Aunt Polly's face. - -"Joe Harper, have you seen my Tom this morning?" - -"No'm." - -"When did you see him last?" - -Joe tried to remember, but was not sure he could say. The people had -stopped moving out of church. Whispers passed along, and a boding -uneasiness took possession of every countenance. Children were -anxiously questioned, and young teachers. They all said they had not -noticed whether Tom and Becky were on board the ferryboat on the -homeward trip; it was dark; no one thought of inquiring if any one was -missing. One young man finally blurted out his fear that they were -still in the cave! Mrs. Thatcher swooned away. Aunt Polly fell to -crying and wringing her hands. - -The alarm swept from lip to lip, from group to group, from street to -street, and within five minutes the bells were wildly clanging and the -whole town was up! The Cardiff Hill episode sank into instant -insignificance, the burglars were forgotten, horses were saddled, -skiffs were manned, the ferryboat ordered out, and before the horror -was half an hour old, two hundred men were pouring down highroad and -river toward the cave. - -All the long afternoon the village seemed empty and dead. Many women -visited Aunt Polly and Mrs. Thatcher and tried to comfort them. They -cried with them, too, and that was still better than words. All the -tedious night the town waited for news; but when the morning dawned at -last, all the word that came was, "Send more candles--and send food." -Mrs. Thatcher was almost crazed; and Aunt Polly, also. Judge Thatcher -sent messages of hope and encouragement from the cave, but they -conveyed no real cheer. - -The old Welshman came home toward daylight, spattered with -candle-grease, smeared with clay, and almost worn out. He found Huck -still in the bed that had been provided for him, and delirious with -fever. The physicians were all at the cave, so the Widow Douglas came -and took charge of the patient. She said she would do her best by him, -because, whether he was good, bad, or indifferent, he was the Lord's, -and nothing that was the Lord's was a thing to be neglected. The -Welshman said Huck had good spots in him, and the widow said: - -"You can depend on it. That's the Lord's mark. He don't leave it off. -He never does. Puts it somewhere on every creature that comes from his -hands." - -Early in the forenoon parties of jaded men began to straggle into the -village, but the strongest of the citizens continued searching. All the -news that could be gained was that remotenesses of the cavern were -being ransacked that had never been visited before; that every corner -and crevice was going to be thoroughly searched; that wherever one -wandered through the maze of passages, lights were to be seen flitting -hither and thither in the distance, and shoutings and pistol-shots sent -their hollow reverberations to the ear down the sombre aisles. In one -place, far from the section usually traversed by tourists, the names -"BECKY & TOM" had been found traced upon the rocky wall with -candle-smoke, and near at hand a grease-soiled bit of ribbon. Mrs. -Thatcher recognized the ribbon and cried over it. She said it was the -last relic she should ever have of her child; and that no other memorial -of her could ever be so precious, because this one parted latest from -the living body before the awful death came. Some said that now and -then, in the cave, a far-away speck of light would glimmer, and then a -glorious shout would burst forth and a score of men go trooping down the -echoing aisle--and then a sickening disappointment always followed; the -children were not there; it was only a searcher's light. - -Three dreadful days and nights dragged their tedious hours along, and -the village sank into a hopeless stupor. No one had heart for anything. -The accidental discovery, just made, that the proprietor of the -Temperance Tavern kept liquor on his premises, scarcely fluttered the -public pulse, tremendous as the fact was. In a lucid interval, Huck -feebly led up to the subject of taverns, and finally asked--dimly -dreading the worst--if anything had been discovered at the Temperance -Tavern since he had been ill. - -"Yes," said the widow. - -Huck started up in bed, wild-eyed: - -"What? What was it?" - -"Liquor!--and the place has been shut up. Lie down, child--what a turn -you did give me!" - -"Only tell me just one thing--only just one--please! Was it Tom Sawyer -that found it?" - -The widow burst into tears. "Hush, hush, child, hush! I've told you -before, you must NOT talk. You are very, very sick!" - -Then nothing but liquor had been found; there would have been a great -powwow if it had been the gold. So the treasure was gone forever--gone -forever! But what could she be crying about? Curious that she should -cry. - -These thoughts worked their dim way through Huck's mind, and under the -weariness they gave him he fell asleep. The widow said to herself: - -"There--he's asleep, poor wreck. Tom Sawyer find it! Pity but somebody -could find Tom Sawyer! Ah, there ain't many left, now, that's got hope -enough, or strength enough, either, to go on searching." - - - -CHAPTER XXXI - -NOW to return to Tom and Becky's share in the picnic. They tripped -along the murky aisles with the rest of the company, visiting the -familiar wonders of the cave--wonders dubbed with rather -over-descriptive names, such as "The Drawing-Room," "The Cathedral," -"Aladdin's Palace," and so on. Presently the hide-and-seek frolicking -began, and Tom and Becky engaged in it with zeal until the exertion -began to grow a trifle wearisome; then they wandered down a sinuous -avenue holding their candles aloft and reading the tangled web-work of -names, dates, post-office addresses, and mottoes with which the rocky -walls had been frescoed (in candle-smoke). Still drifting along and -talking, they scarcely noticed that they were now in a part of the cave -whose walls were not frescoed. They smoked their own names under an -overhanging shelf and moved on. Presently they came to a place where a -little stream of water, trickling over a ledge and carrying a limestone -sediment with it, had, in the slow-dragging ages, formed a laced and -ruffled Niagara in gleaming and imperishable stone. Tom squeezed his -small body behind it in order to illuminate it for Becky's -gratification. He found that it curtained a sort of steep natural -stairway which was enclosed between narrow walls, and at once the -ambition to be a discoverer seized him. Becky responded to his call, -and they made a smoke-mark for future guidance, and started upon their -quest. They wound this way and that, far down into the secret depths of -the cave, made another mark, and branched off in search of novelties to -tell the upper world about. In one place they found a spacious cavern, -from whose ceiling depended a multitude of shining stalactites of the -length and circumference of a man's leg; they walked all about it, -wondering and admiring, and presently left it by one of the numerous -passages that opened into it. This shortly brought them to a bewitching -spring, whose basin was incrusted with a frostwork of glittering -crystals; it was in the midst of a cavern whose walls were supported by -many fantastic pillars which had been formed by the joining of great -stalactites and stalagmites together, the result of the ceaseless -water-drip of centuries. Under the roof vast knots of bats had packed -themselves together, thousands in a bunch; the lights disturbed the -creatures and they came flocking down by hundreds, squeaking and -darting furiously at the candles. Tom knew their ways and the danger of -this sort of conduct. He seized Becky's hand and hurried her into the -first corridor that offered; and none too soon, for a bat struck -Becky's light out with its wing while she was passing out of the -cavern. The bats chased the children a good distance; but the fugitives -plunged into every new passage that offered, and at last got rid of the -perilous things. Tom found a subterranean lake, shortly, which -stretched its dim length away until its shape was lost in the shadows. -He wanted to explore its borders, but concluded that it would be best -to sit down and rest awhile, first. Now, for the first time, the deep -stillness of the place laid a clammy hand upon the spirits of the -children. Becky said: - -"Why, I didn't notice, but it seems ever so long since I heard any of -the others." - -"Come to think, Becky, we are away down below them--and I don't know -how far away north, or south, or east, or whichever it is. We couldn't -hear them here." - -Becky grew apprehensive. - -"I wonder how long we've been down here, Tom? We better start back." - -"Yes, I reckon we better. P'raps we better." - -"Can you find the way, Tom? It's all a mixed-up crookedness to me." - -"I reckon I could find it--but then the bats. If they put our candles -out it will be an awful fix. Let's try some other way, so as not to go -through there." - -"Well. But I hope we won't get lost. It would be so awful!" and the -girl shuddered at the thought of the dreadful possibilities. - -They started through a corridor, and traversed it in silence a long -way, glancing at each new opening, to see if there was anything -familiar about the look of it; but they were all strange. Every time -Tom made an examination, Becky would watch his face for an encouraging -sign, and he would say cheerily: - -"Oh, it's all right. This ain't the one, but we'll come to it right -away!" - -But he felt less and less hopeful with each failure, and presently -began to turn off into diverging avenues at sheer random, in desperate -hope of finding the one that was wanted. He still said it was "all -right," but there was such a leaden dread at his heart that the words -had lost their ring and sounded just as if he had said, "All is lost!" -Becky clung to his side in an anguish of fear, and tried hard to keep -back the tears, but they would come. At last she said: - -"Oh, Tom, never mind the bats, let's go back that way! We seem to get -worse and worse off all the time." - -"Listen!" said he. - -Profound silence; silence so deep that even their breathings were -conspicuous in the hush. Tom shouted. The call went echoing down the -empty aisles and died out in the distance in a faint sound that -resembled a ripple of mocking laughter. - -"Oh, don't do it again, Tom, it is too horrid," said Becky. - -"It is horrid, but I better, Becky; they might hear us, you know," and -he shouted again. - -The "might" was even a chillier horror than the ghostly laughter, it -so confessed a perishing hope. The children stood still and listened; -but there was no result. Tom turned upon the back track at once, and -hurried his steps. It was but a little while before a certain -indecision in his manner revealed another fearful fact to Becky--he -could not find his way back! - -"Oh, Tom, you didn't make any marks!" - -"Becky, I was such a fool! Such a fool! I never thought we might want -to come back! No--I can't find the way. It's all mixed up." - -"Tom, Tom, we're lost! we're lost! We never can get out of this awful -place! Oh, why DID we ever leave the others!" - -She sank to the ground and burst into such a frenzy of crying that Tom -was appalled with the idea that she might die, or lose her reason. He -sat down by her and put his arms around her; she buried her face in his -bosom, she clung to him, she poured out her terrors, her unavailing -regrets, and the far echoes turned them all to jeering laughter. Tom -begged her to pluck up hope again, and she said she could not. He fell -to blaming and abusing himself for getting her into this miserable -situation; this had a better effect. She said she would try to hope -again, she would get up and follow wherever he might lead if only he -would not talk like that any more. For he was no more to blame than -she, she said. - -So they moved on again--aimlessly--simply at random--all they could do -was to move, keep moving. For a little while, hope made a show of -reviving--not with any reason to back it, but only because it is its -nature to revive when the spring has not been taken out of it by age -and familiarity with failure. - -By-and-by Tom took Becky's candle and blew it out. This economy meant -so much! Words were not needed. Becky understood, and her hope died -again. She knew that Tom had a whole candle and three or four pieces in -his pockets--yet he must economize. - -By-and-by, fatigue began to assert its claims; the children tried to -pay attention, for it was dreadful to think of sitting down when time -was grown to be so precious, moving, in some direction, in any -direction, was at least progress and might bear fruit; but to sit down -was to invite death and shorten its pursuit. - -At last Becky's frail limbs refused to carry her farther. She sat -down. Tom rested with her, and they talked of home, and the friends -there, and the comfortable beds and, above all, the light! Becky cried, -and Tom tried to think of some way of comforting her, but all his -encouragements were grown threadbare with use, and sounded like -sarcasms. Fatigue bore so heavily upon Becky that she drowsed off to -sleep. Tom was grateful. He sat looking into her drawn face and saw it -grow smooth and natural under the influence of pleasant dreams; and -by-and-by a smile dawned and rested there. The peaceful face reflected -somewhat of peace and healing into his own spirit, and his thoughts -wandered away to bygone times and dreamy memories. While he was deep in -his musings, Becky woke up with a breezy little laugh--but it was -stricken dead upon her lips, and a groan followed it. - -"Oh, how COULD I sleep! I wish I never, never had waked! No! No, I -don't, Tom! Don't look so! I won't say it again." - -"I'm glad you've slept, Becky; you'll feel rested, now, and we'll find -the way out." - -"We can try, Tom; but I've seen such a beautiful country in my dream. -I reckon we are going there." - -"Maybe not, maybe not. Cheer up, Becky, and let's go on trying." - -They rose up and wandered along, hand in hand and hopeless. They tried -to estimate how long they had been in the cave, but all they knew was -that it seemed days and weeks, and yet it was plain that this could not -be, for their candles were not gone yet. A long time after this--they -could not tell how long--Tom said they must go softly and listen for -dripping water--they must find a spring. They found one presently, and -Tom said it was time to rest again. Both were cruelly tired, yet Becky -said she thought she could go a little farther. She was surprised to -hear Tom dissent. She could not understand it. They sat down, and Tom -fastened his candle to the wall in front of them with some clay. -Thought was soon busy; nothing was said for some time. Then Becky broke -the silence: - -"Tom, I am so hungry!" - -Tom took something out of his pocket. - -"Do you remember this?" said he. - -Becky almost smiled. - -"It's our wedding-cake, Tom." - -"Yes--I wish it was as big as a barrel, for it's all we've got." - -"I saved it from the picnic for us to dream on, Tom, the way grown-up -people do with wedding-cake--but it'll be our--" - -She dropped the sentence where it was. Tom divided the cake and Becky -ate with good appetite, while Tom nibbled at his moiety. There was -abundance of cold water to finish the feast with. By-and-by Becky -suggested that they move on again. Tom was silent a moment. Then he -said: - -"Becky, can you bear it if I tell you something?" - -Becky's face paled, but she thought she could. - -"Well, then, Becky, we must stay here, where there's water to drink. -That little piece is our last candle!" - -Becky gave loose to tears and wailings. Tom did what he could to -comfort her, but with little effect. At length Becky said: - -"Tom!" - -"Well, Becky?" - -"They'll miss us and hunt for us!" - -"Yes, they will! Certainly they will!" - -"Maybe they're hunting for us now, Tom." - -"Why, I reckon maybe they are. I hope they are." - -"When would they miss us, Tom?" - -"When they get back to the boat, I reckon." - -"Tom, it might be dark then--would they notice we hadn't come?" - -"I don't know. But anyway, your mother would miss you as soon as they -got home." - -A frightened look in Becky's face brought Tom to his senses and he saw -that he had made a blunder. Becky was not to have gone home that night! -The children became silent and thoughtful. In a moment a new burst of -grief from Becky showed Tom that the thing in his mind had struck hers -also--that the Sabbath morning might be half spent before Mrs. Thatcher -discovered that Becky was not at Mrs. Harper's. - -The children fastened their eyes upon their bit of candle and watched -it melt slowly and pitilessly away; saw the half inch of wick stand -alone at last; saw the feeble flame rise and fall, climb the thin -column of smoke, linger at its top a moment, and then--the horror of -utter darkness reigned! - -How long afterward it was that Becky came to a slow consciousness that -she was crying in Tom's arms, neither could tell. All that they knew -was, that after what seemed a mighty stretch of time, both awoke out of -a dead stupor of sleep and resumed their miseries once more. Tom said -it might be Sunday, now--maybe Monday. He tried to get Becky to talk, -but her sorrows were too oppressive, all her hopes were gone. Tom said -that they must have been missed long ago, and no doubt the search was -going on. He would shout and maybe some one would come. He tried it; -but in the darkness the distant echoes sounded so hideously that he -tried it no more. - -The hours wasted away, and hunger came to torment the captives again. -A portion of Tom's half of the cake was left; they divided and ate it. -But they seemed hungrier than before. The poor morsel of food only -whetted desire. - -By-and-by Tom said: - -"SH! Did you hear that?" - -Both held their breath and listened. There was a sound like the -faintest, far-off shout. Instantly Tom answered it, and leading Becky -by the hand, started groping down the corridor in its direction. -Presently he listened again; again the sound was heard, and apparently -a little nearer. - -"It's them!" said Tom; "they're coming! Come along, Becky--we're all -right now!" - -The joy of the prisoners was almost overwhelming. Their speed was -slow, however, because pitfalls were somewhat common, and had to be -guarded against. They shortly came to one and had to stop. It might be -three feet deep, it might be a hundred--there was no passing it at any -rate. Tom got down on his breast and reached as far down as he could. -No bottom. They must stay there and wait until the searchers came. They -listened; evidently the distant shoutings were growing more distant! a -moment or two more and they had gone altogether. The heart-sinking -misery of it! Tom whooped until he was hoarse, but it was of no use. He -talked hopefully to Becky; but an age of anxious waiting passed and no -sounds came again. - -The children groped their way back to the spring. The weary time -dragged on; they slept again, and awoke famished and woe-stricken. Tom -believed it must be Tuesday by this time. - -Now an idea struck him. There were some side passages near at hand. It -would be better to explore some of these than bear the weight of the -heavy time in idleness. He took a kite-line from his pocket, tied it to -a projection, and he and Becky started, Tom in the lead, unwinding the -line as he groped along. At the end of twenty steps the corridor ended -in a "jumping-off place." Tom got down on his knees and felt below, and -then as far around the corner as he could reach with his hands -conveniently; he made an effort to stretch yet a little farther to the -right, and at that moment, not twenty yards away, a human hand, holding -a candle, appeared from behind a rock! Tom lifted up a glorious shout, -and instantly that hand was followed by the body it belonged to--Injun -Joe's! Tom was paralyzed; he could not move. He was vastly gratified -the next moment, to see the "Spaniard" take to his heels and get -himself out of sight. Tom wondered that Joe had not recognized his -voice and come over and killed him for testifying in court. But the -echoes must have disguised the voice. Without doubt, that was it, he -reasoned. Tom's fright weakened every muscle in his body. He said to -himself that if he had strength enough to get back to the spring he -would stay there, and nothing should tempt him to run the risk of -meeting Injun Joe again. He was careful to keep from Becky what it was -he had seen. He told her he had only shouted "for luck." - -But hunger and wretchedness rise superior to fears in the long run. -Another tedious wait at the spring and another long sleep brought -changes. The children awoke tortured with a raging hunger. Tom believed -that it must be Wednesday or Thursday or even Friday or Saturday, now, -and that the search had been given over. He proposed to explore another -passage. He felt willing to risk Injun Joe and all other terrors. But -Becky was very weak. She had sunk into a dreary apathy and would not be -roused. She said she would wait, now, where she was, and die--it would -not be long. She told Tom to go with the kite-line and explore if he -chose; but she implored him to come back every little while and speak -to her; and she made him promise that when the awful time came, he -would stay by her and hold her hand until all was over. - -Tom kissed her, with a choking sensation in his throat, and made a -show of being confident of finding the searchers or an escape from the -cave; then he took the kite-line in his hand and went groping down one -of the passages on his hands and knees, distressed with hunger and sick -with bodings of coming doom. - - - -CHAPTER XXXII - -TUESDAY afternoon came, and waned to the twilight. The village of St. -Petersburg still mourned. The lost children had not been found. Public -prayers had been offered up for them, and many and many a private -prayer that had the petitioner's whole heart in it; but still no good -news came from the cave. The majority of the searchers had given up the -quest and gone back to their daily avocations, saying that it was plain -the children could never be found. Mrs. Thatcher was very ill, and a -great part of the time delirious. People said it was heartbreaking to -hear her call her child, and raise her head and listen a whole minute -at a time, then lay it wearily down again with a moan. Aunt Polly had -drooped into a settled melancholy, and her gray hair had grown almost -white. The village went to its rest on Tuesday night, sad and forlorn. - -Away in the middle of the night a wild peal burst from the village -bells, and in a moment the streets were swarming with frantic half-clad -people, who shouted, "Turn out! turn out! they're found! they're -found!" Tin pans and horns were added to the din, the population massed -itself and moved toward the river, met the children coming in an open -carriage drawn by shouting citizens, thronged around it, joined its -homeward march, and swept magnificently up the main street roaring -huzzah after huzzah! - -The village was illuminated; nobody went to bed again; it was the -greatest night the little town had ever seen. During the first half-hour -a procession of villagers filed through Judge Thatcher's house, seized -the saved ones and kissed them, squeezed Mrs. Thatcher's hand, tried to -speak but couldn't--and drifted out raining tears all over the place. - -Aunt Polly's happiness was complete, and Mrs. Thatcher's nearly so. It -would be complete, however, as soon as the messenger dispatched with -the great news to the cave should get the word to her husband. Tom lay -upon a sofa with an eager auditory about him and told the history of -the wonderful adventure, putting in many striking additions to adorn it -withal; and closed with a description of how he left Becky and went on -an exploring expedition; how he followed two avenues as far as his -kite-line would reach; how he followed a third to the fullest stretch of -the kite-line, and was about to turn back when he glimpsed a far-off -speck that looked like daylight; dropped the line and groped toward it, -pushed his head and shoulders through a small hole, and saw the broad -Mississippi rolling by! And if it had only happened to be night he would -not have seen that speck of daylight and would not have explored that -passage any more! He told how he went back for Becky and broke the good -news and she told him not to fret her with such stuff, for she was -tired, and knew she was going to die, and wanted to. He described how he -labored with her and convinced her; and how she almost died for joy when -she had groped to where she actually saw the blue speck of daylight; how -he pushed his way out at the hole and then helped her out; how they sat -there and cried for gladness; how some men came along in a skiff and Tom -hailed them and told them their situation and their famished condition; -how the men didn't believe the wild tale at first, "because," said they, -"you are five miles down the river below the valley the cave is in" ---then took them aboard, rowed to a house, gave them supper, made them -rest till two or three hours after dark and then brought them home. - -Before day-dawn, Judge Thatcher and the handful of searchers with him -were tracked out, in the cave, by the twine clews they had strung -behind them, and informed of the great news. - -Three days and nights of toil and hunger in the cave were not to be -shaken off at once, as Tom and Becky soon discovered. They were -bedridden all of Wednesday and Thursday, and seemed to grow more and -more tired and worn, all the time. Tom got about, a little, on -Thursday, was down-town Friday, and nearly as whole as ever Saturday; -but Becky did not leave her room until Sunday, and then she looked as -if she had passed through a wasting illness. - -Tom learned of Huck's sickness and went to see him on Friday, but -could not be admitted to the bedroom; neither could he on Saturday or -Sunday. He was admitted daily after that, but was warned to keep still -about his adventure and introduce no exciting topic. The Widow Douglas -stayed by to see that he obeyed. At home Tom learned of the Cardiff -Hill event; also that the "ragged man's" body had eventually been found -in the river near the ferry-landing; he had been drowned while trying -to escape, perhaps. - -About a fortnight after Tom's rescue from the cave, he started off to -visit Huck, who had grown plenty strong enough, now, to hear exciting -talk, and Tom had some that would interest him, he thought. Judge -Thatcher's house was on Tom's way, and he stopped to see Becky. The -Judge and some friends set Tom to talking, and some one asked him -ironically if he wouldn't like to go to the cave again. Tom said he -thought he wouldn't mind it. The Judge said: - -"Well, there are others just like you, Tom, I've not the least doubt. -But we have taken care of that. Nobody will get lost in that cave any -more." - -"Why?" - -"Because I had its big door sheathed with boiler iron two weeks ago, -and triple-locked--and I've got the keys." - -Tom turned as white as a sheet. - -"What's the matter, boy! Here, run, somebody! Fetch a glass of water!" - -The water was brought and thrown into Tom's face. - -"Ah, now you're all right. What was the matter with you, Tom?" - -"Oh, Judge, Injun Joe's in the cave!" - - - -CHAPTER XXXIII - -WITHIN a few minutes the news had spread, and a dozen skiff-loads of -men were on their way to McDougal's cave, and the ferryboat, well -filled with passengers, soon followed. Tom Sawyer was in the skiff that -bore Judge Thatcher. - -When the cave door was unlocked, a sorrowful sight presented itself in -the dim twilight of the place. Injun Joe lay stretched upon the ground, -dead, with his face close to the crack of the door, as if his longing -eyes had been fixed, to the latest moment, upon the light and the cheer -of the free world outside. Tom was touched, for he knew by his own -experience how this wretch had suffered. His pity was moved, but -nevertheless he felt an abounding sense of relief and security, now, -which revealed to him in a degree which he had not fully appreciated -before how vast a weight of dread had been lying upon him since the day -he lifted his voice against this bloody-minded outcast. - -Injun Joe's bowie-knife lay close by, its blade broken in two. The -great foundation-beam of the door had been chipped and hacked through, -with tedious labor; useless labor, too, it was, for the native rock -formed a sill outside it, and upon that stubborn material the knife had -wrought no effect; the only damage done was to the knife itself. But if -there had been no stony obstruction there the labor would have been -useless still, for if the beam had been wholly cut away Injun Joe could -not have squeezed his body under the door, and he knew it. So he had -only hacked that place in order to be doing something--in order to pass -the weary time--in order to employ his tortured faculties. Ordinarily -one could find half a dozen bits of candle stuck around in the crevices -of this vestibule, left there by tourists; but there were none now. The -prisoner had searched them out and eaten them. He had also contrived to -catch a few bats, and these, also, he had eaten, leaving only their -claws. The poor unfortunate had starved to death. In one place, near at -hand, a stalagmite had been slowly growing up from the ground for ages, -builded by the water-drip from a stalactite overhead. The captive had -broken off the stalagmite, and upon the stump had placed a stone, -wherein he had scooped a shallow hollow to catch the precious drop -that fell once in every three minutes with the dreary regularity of a -clock-tick--a dessertspoonful once in four and twenty hours. That drop -was falling when the Pyramids were new; when Troy fell; when the -foundations of Rome were laid; when Christ was crucified; when the -Conqueror created the British empire; when Columbus sailed; when the -massacre at Lexington was "news." It is falling now; it will still be -falling when all these things shall have sunk down the afternoon of -history, and the twilight of tradition, and been swallowed up in the -thick night of oblivion. Has everything a purpose and a mission? Did -this drop fall patiently during five thousand years to be ready for -this flitting human insect's need? and has it another important object -to accomplish ten thousand years to come? No matter. It is many and -many a year since the hapless half-breed scooped out the stone to catch -the priceless drops, but to this day the tourist stares longest at that -pathetic stone and that slow-dropping water when he comes to see the -wonders of McDougal's cave. Injun Joe's cup stands first in the list of -the cavern's marvels; even "Aladdin's Palace" cannot rival it. - -Injun Joe was buried near the mouth of the cave; and people flocked -there in boats and wagons from the towns and from all the farms and -hamlets for seven miles around; they brought their children, and all -sorts of provisions, and confessed that they had had almost as -satisfactory a time at the funeral as they could have had at the -hanging. - -This funeral stopped the further growth of one thing--the petition to -the governor for Injun Joe's pardon. The petition had been largely -signed; many tearful and eloquent meetings had been held, and a -committee of sappy women been appointed to go in deep mourning and wail -around the governor, and implore him to be a merciful ass and trample -his duty under foot. Injun Joe was believed to have killed five -citizens of the village, but what of that? If he had been Satan himself -there would have been plenty of weaklings ready to scribble their names -to a pardon-petition, and drip a tear on it from their permanently -impaired and leaky water-works. - -The morning after the funeral Tom took Huck to a private place to have -an important talk. Huck had learned all about Tom's adventure from the -Welshman and the Widow Douglas, by this time, but Tom said he reckoned -there was one thing they had not told him; that thing was what he -wanted to talk about now. Huck's face saddened. He said: - -"I know what it is. You got into No. 2 and never found anything but -whiskey. Nobody told me it was you; but I just knowed it must 'a' ben -you, soon as I heard 'bout that whiskey business; and I knowed you -hadn't got the money becuz you'd 'a' got at me some way or other and -told me even if you was mum to everybody else. Tom, something's always -told me we'd never get holt of that swag." - -"Why, Huck, I never told on that tavern-keeper. YOU know his tavern -was all right the Saturday I went to the picnic. Don't you remember you -was to watch there that night?" - -"Oh yes! Why, it seems 'bout a year ago. It was that very night that I -follered Injun Joe to the widder's." - -"YOU followed him?" - -"Yes--but you keep mum. I reckon Injun Joe's left friends behind him, -and I don't want 'em souring on me and doing me mean tricks. If it -hadn't ben for me he'd be down in Texas now, all right." - -Then Huck told his entire adventure in confidence to Tom, who had only -heard of the Welshman's part of it before. - -"Well," said Huck, presently, coming back to the main question, -"whoever nipped the whiskey in No. 2, nipped the money, too, I reckon ---anyways it's a goner for us, Tom." - -"Huck, that money wasn't ever in No. 2!" - -"What!" Huck searched his comrade's face keenly. "Tom, have you got on -the track of that money again?" - -"Huck, it's in the cave!" - -Huck's eyes blazed. - -"Say it again, Tom." - -"The money's in the cave!" - -"Tom--honest injun, now--is it fun, or earnest?" - -"Earnest, Huck--just as earnest as ever I was in my life. Will you go -in there with me and help get it out?" - -"I bet I will! I will if it's where we can blaze our way to it and not -get lost." - -"Huck, we can do that without the least little bit of trouble in the -world." - -"Good as wheat! What makes you think the money's--" - -"Huck, you just wait till we get in there. If we don't find it I'll -agree to give you my drum and every thing I've got in the world. I -will, by jings." - -"All right--it's a whiz. When do you say?" - -"Right now, if you say it. Are you strong enough?" - -"Is it far in the cave? I ben on my pins a little, three or four days, -now, but I can't walk more'n a mile, Tom--least I don't think I could." - -"It's about five mile into there the way anybody but me would go, -Huck, but there's a mighty short cut that they don't anybody but me -know about. Huck, I'll take you right to it in a skiff. I'll float the -skiff down there, and I'll pull it back again all by myself. You -needn't ever turn your hand over." - -"Less start right off, Tom." - -"All right. We want some bread and meat, and our pipes, and a little -bag or two, and two or three kite-strings, and some of these -new-fangled things they call lucifer matches. I tell you, many's -the time I wished I had some when I was in there before." - -A trifle after noon the boys borrowed a small skiff from a citizen who -was absent, and got under way at once. When they were several miles -below "Cave Hollow," Tom said: - -"Now you see this bluff here looks all alike all the way down from the -cave hollow--no houses, no wood-yards, bushes all alike. But do you see -that white place up yonder where there's been a landslide? Well, that's -one of my marks. We'll get ashore, now." - -They landed. - -"Now, Huck, where we're a-standing you could touch that hole I got out -of with a fishing-pole. See if you can find it." - -Huck searched all the place about, and found nothing. Tom proudly -marched into a thick clump of sumach bushes and said: - -"Here you are! Look at it, Huck; it's the snuggest hole in this -country. You just keep mum about it. All along I've been wanting to be -a robber, but I knew I'd got to have a thing like this, and where to -run across it was the bother. We've got it now, and we'll keep it -quiet, only we'll let Joe Harper and Ben Rogers in--because of course -there's got to be a Gang, or else there wouldn't be any style about it. -Tom Sawyer's Gang--it sounds splendid, don't it, Huck?" - -"Well, it just does, Tom. And who'll we rob?" - -"Oh, most anybody. Waylay people--that's mostly the way." - -"And kill them?" - -"No, not always. Hive them in the cave till they raise a ransom." - -"What's a ransom?" - -"Money. You make them raise all they can, off'n their friends; and -after you've kept them a year, if it ain't raised then you kill them. -That's the general way. Only you don't kill the women. You shut up the -women, but you don't kill them. They're always beautiful and rich, and -awfully scared. You take their watches and things, but you always take -your hat off and talk polite. They ain't anybody as polite as robbers ---you'll see that in any book. Well, the women get to loving you, and -after they've been in the cave a week or two weeks they stop crying and -after that you couldn't get them to leave. If you drove them out they'd -turn right around and come back. It's so in all the books." - -"Why, it's real bully, Tom. I believe it's better'n to be a pirate." - -"Yes, it's better in some ways, because it's close to home and -circuses and all that." - -By this time everything was ready and the boys entered the hole, Tom -in the lead. They toiled their way to the farther end of the tunnel, -then made their spliced kite-strings fast and moved on. A few steps -brought them to the spring, and Tom felt a shudder quiver all through -him. He showed Huck the fragment of candle-wick perched on a lump of -clay against the wall, and described how he and Becky had watched the -flame struggle and expire. - -The boys began to quiet down to whispers, now, for the stillness and -gloom of the place oppressed their spirits. They went on, and presently -entered and followed Tom's other corridor until they reached the -"jumping-off place." The candles revealed the fact that it was not -really a precipice, but only a steep clay hill twenty or thirty feet -high. Tom whispered: - -"Now I'll show you something, Huck." - -He held his candle aloft and said: - -"Look as far around the corner as you can. Do you see that? There--on -the big rock over yonder--done with candle-smoke." - -"Tom, it's a CROSS!" - -"NOW where's your Number Two? 'UNDER THE CROSS,' hey? Right yonder's -where I saw Injun Joe poke up his candle, Huck!" - -Huck stared at the mystic sign awhile, and then said with a shaky voice: - -"Tom, less git out of here!" - -"What! and leave the treasure?" - -"Yes--leave it. Injun Joe's ghost is round about there, certain." - -"No it ain't, Huck, no it ain't. It would ha'nt the place where he -died--away out at the mouth of the cave--five mile from here." - -"No, Tom, it wouldn't. It would hang round the money. I know the ways -of ghosts, and so do you." - -Tom began to fear that Huck was right. Misgivings gathered in his -mind. But presently an idea occurred to him-- - -"Lookyhere, Huck, what fools we're making of ourselves! Injun Joe's -ghost ain't a going to come around where there's a cross!" - -The point was well taken. It had its effect. - -"Tom, I didn't think of that. But that's so. It's luck for us, that -cross is. I reckon we'll climb down there and have a hunt for that box." - -Tom went first, cutting rude steps in the clay hill as he descended. -Huck followed. Four avenues opened out of the small cavern which the -great rock stood in. The boys examined three of them with no result. -They found a small recess in the one nearest the base of the rock, with -a pallet of blankets spread down in it; also an old suspender, some -bacon rind, and the well-gnawed bones of two or three fowls. But there -was no money-box. The lads searched and researched this place, but in -vain. Tom said: - -"He said UNDER the cross. Well, this comes nearest to being under the -cross. It can't be under the rock itself, because that sets solid on -the ground." - -They searched everywhere once more, and then sat down discouraged. -Huck could suggest nothing. By-and-by Tom said: - -"Lookyhere, Huck, there's footprints and some candle-grease on the -clay about one side of this rock, but not on the other sides. Now, -what's that for? I bet you the money IS under the rock. I'm going to -dig in the clay." - -"That ain't no bad notion, Tom!" said Huck with animation. - -Tom's "real Barlow" was out at once, and he had not dug four inches -before he struck wood. - -"Hey, Huck!--you hear that?" - -Huck began to dig and scratch now. Some boards were soon uncovered and -removed. They had concealed a natural chasm which led under the rock. -Tom got into this and held his candle as far under the rock as he -could, but said he could not see to the end of the rift. He proposed to -explore. He stooped and passed under; the narrow way descended -gradually. He followed its winding course, first to the right, then to -the left, Huck at his heels. Tom turned a short curve, by-and-by, and -exclaimed: - -"My goodness, Huck, lookyhere!" - -It was the treasure-box, sure enough, occupying a snug little cavern, -along with an empty powder-keg, a couple of guns in leather cases, two -or three pairs of old moccasins, a leather belt, and some other rubbish -well soaked with the water-drip. - -"Got it at last!" said Huck, ploughing among the tarnished coins with -his hand. "My, but we're rich, Tom!" - -"Huck, I always reckoned we'd get it. It's just too good to believe, -but we HAVE got it, sure! Say--let's not fool around here. Let's snake -it out. Lemme see if I can lift the box." - -It weighed about fifty pounds. Tom could lift it, after an awkward -fashion, but could not carry it conveniently. - -"I thought so," he said; "THEY carried it like it was heavy, that day -at the ha'nted house. I noticed that. I reckon I was right to think of -fetching the little bags along." - -The money was soon in the bags and the boys took it up to the cross -rock. - -"Now less fetch the guns and things," said Huck. - -"No, Huck--leave them there. They're just the tricks to have when we -go to robbing. We'll keep them there all the time, and we'll hold our -orgies there, too. It's an awful snug place for orgies." - -"What orgies?" - -"I dono. But robbers always have orgies, and of course we've got to -have them, too. Come along, Huck, we've been in here a long time. It's -getting late, I reckon. I'm hungry, too. We'll eat and smoke when we -get to the skiff." - -They presently emerged into the clump of sumach bushes, looked warily -out, found the coast clear, and were soon lunching and smoking in the -skiff. As the sun dipped toward the horizon they pushed out and got -under way. Tom skimmed up the shore through the long twilight, chatting -cheerily with Huck, and landed shortly after dark. - -"Now, Huck," said Tom, "we'll hide the money in the loft of the -widow's woodshed, and I'll come up in the morning and we'll count it -and divide, and then we'll hunt up a place out in the woods for it -where it will be safe. Just you lay quiet here and watch the stuff till -I run and hook Benny Taylor's little wagon; I won't be gone a minute." - -He disappeared, and presently returned with the wagon, put the two -small sacks into it, threw some old rags on top of them, and started -off, dragging his cargo behind him. When the boys reached the -Welshman's house, they stopped to rest. Just as they were about to move -on, the Welshman stepped out and said: - -"Hallo, who's that?" - -"Huck and Tom Sawyer." - -"Good! Come along with me, boys, you are keeping everybody waiting. -Here--hurry up, trot ahead--I'll haul the wagon for you. Why, it's not -as light as it might be. Got bricks in it?--or old metal?" - -"Old metal," said Tom. - -"I judged so; the boys in this town will take more trouble and fool -away more time hunting up six bits' worth of old iron to sell to the -foundry than they would to make twice the money at regular work. But -that's human nature--hurry along, hurry along!" - -The boys wanted to know what the hurry was about. - -"Never mind; you'll see, when we get to the Widow Douglas'." - -Huck said with some apprehension--for he was long used to being -falsely accused: - -"Mr. Jones, we haven't been doing nothing." - -The Welshman laughed. - -"Well, I don't know, Huck, my boy. I don't know about that. Ain't you -and the widow good friends?" - -"Yes. Well, she's ben good friends to me, anyway." - -"All right, then. What do you want to be afraid for?" - -This question was not entirely answered in Huck's slow mind before he -found himself pushed, along with Tom, into Mrs. Douglas' drawing-room. -Mr. Jones left the wagon near the door and followed. - -The place was grandly lighted, and everybody that was of any -consequence in the village was there. The Thatchers were there, the -Harpers, the Rogerses, Aunt Polly, Sid, Mary, the minister, the editor, -and a great many more, and all dressed in their best. The widow -received the boys as heartily as any one could well receive two such -looking beings. They were covered with clay and candle-grease. Aunt -Polly blushed crimson with humiliation, and frowned and shook her head -at Tom. Nobody suffered half as much as the two boys did, however. Mr. -Jones said: - -"Tom wasn't at home, yet, so I gave him up; but I stumbled on him and -Huck right at my door, and so I just brought them along in a hurry." - -"And you did just right," said the widow. "Come with me, boys." - -She took them to a bedchamber and said: - -"Now wash and dress yourselves. Here are two new suits of clothes ---shirts, socks, everything complete. They're Huck's--no, no thanks, -Huck--Mr. Jones bought one and I the other. But they'll fit both of you. -Get into them. We'll wait--come down when you are slicked up enough." - -Then she left. - - - -CHAPTER XXXIV - -HUCK said: "Tom, we can slope, if we can find a rope. The window ain't -high from the ground." - -"Shucks! what do you want to slope for?" - -"Well, I ain't used to that kind of a crowd. I can't stand it. I ain't -going down there, Tom." - -"Oh, bother! It ain't anything. I don't mind it a bit. I'll take care -of you." - -Sid appeared. - -"Tom," said he, "auntie has been waiting for you all the afternoon. -Mary got your Sunday clothes ready, and everybody's been fretting about -you. Say--ain't this grease and clay, on your clothes?" - -"Now, Mr. Siddy, you jist 'tend to your own business. What's all this -blow-out about, anyway?" - -"It's one of the widow's parties that she's always having. This time -it's for the Welshman and his sons, on account of that scrape they -helped her out of the other night. And say--I can tell you something, -if you want to know." - -"Well, what?" - -"Why, old Mr. Jones is going to try to spring something on the people -here to-night, but I overheard him tell auntie to-day about it, as a -secret, but I reckon it's not much of a secret now. Everybody knows ---the widow, too, for all she tries to let on she don't. Mr. Jones was -bound Huck should be here--couldn't get along with his grand secret -without Huck, you know!" - -"Secret about what, Sid?" - -"About Huck tracking the robbers to the widow's. I reckon Mr. Jones -was going to make a grand time over his surprise, but I bet you it will -drop pretty flat." - -Sid chuckled in a very contented and satisfied way. - -"Sid, was it you that told?" - -"Oh, never mind who it was. SOMEBODY told--that's enough." - -"Sid, there's only one person in this town mean enough to do that, and -that's you. If you had been in Huck's place you'd 'a' sneaked down the -hill and never told anybody on the robbers. You can't do any but mean -things, and you can't bear to see anybody praised for doing good ones. -There--no thanks, as the widow says"--and Tom cuffed Sid's ears and -helped him to the door with several kicks. "Now go and tell auntie if -you dare--and to-morrow you'll catch it!" - -Some minutes later the widow's guests were at the supper-table, and a -dozen children were propped up at little side-tables in the same room, -after the fashion of that country and that day. At the proper time Mr. -Jones made his little speech, in which he thanked the widow for the -honor she was doing himself and his sons, but said that there was -another person whose modesty-- - -And so forth and so on. He sprung his secret about Huck's share in the -adventure in the finest dramatic manner he was master of, but the -surprise it occasioned was largely counterfeit and not as clamorous and -effusive as it might have been under happier circumstances. However, -the widow made a pretty fair show of astonishment, and heaped so many -compliments and so much gratitude upon Huck that he almost forgot the -nearly intolerable discomfort of his new clothes in the entirely -intolerable discomfort of being set up as a target for everybody's gaze -and everybody's laudations. - -The widow said she meant to give Huck a home under her roof and have -him educated; and that when she could spare the money she would start -him in business in a modest way. Tom's chance was come. He said: - -"Huck don't need it. Huck's rich." - -Nothing but a heavy strain upon the good manners of the company kept -back the due and proper complimentary laugh at this pleasant joke. But -the silence was a little awkward. Tom broke it: - -"Huck's got money. Maybe you don't believe it, but he's got lots of -it. Oh, you needn't smile--I reckon I can show you. You just wait a -minute." - -Tom ran out of doors. The company looked at each other with a -perplexed interest--and inquiringly at Huck, who was tongue-tied. - -"Sid, what ails Tom?" said Aunt Polly. "He--well, there ain't ever any -making of that boy out. I never--" - -Tom entered, struggling with the weight of his sacks, and Aunt Polly -did not finish her sentence. Tom poured the mass of yellow coin upon -the table and said: - -"There--what did I tell you? Half of it's Huck's and half of it's mine!" - -The spectacle took the general breath away. All gazed, nobody spoke -for a moment. Then there was a unanimous call for an explanation. Tom -said he could furnish it, and he did. The tale was long, but brimful of -interest. There was scarcely an interruption from any one to break the -charm of its flow. When he had finished, Mr. Jones said: - -"I thought I had fixed up a little surprise for this occasion, but it -don't amount to anything now. This one makes it sing mighty small, I'm -willing to allow." - -The money was counted. The sum amounted to a little over twelve -thousand dollars. It was more than any one present had ever seen at one -time before, though several persons were there who were worth -considerably more than that in property. - - - -CHAPTER XXXV - -THE reader may rest satisfied that Tom's and Huck's windfall made a -mighty stir in the poor little village of St. Petersburg. So vast a -sum, all in actual cash, seemed next to incredible. It was talked -about, gloated over, glorified, until the reason of many of the -citizens tottered under the strain of the unhealthy excitement. Every -"haunted" house in St. Petersburg and the neighboring villages was -dissected, plank by plank, and its foundations dug up and ransacked for -hidden treasure--and not by boys, but men--pretty grave, unromantic -men, too, some of them. Wherever Tom and Huck appeared they were -courted, admired, stared at. The boys were not able to remember that -their remarks had possessed weight before; but now their sayings were -treasured and repeated; everything they did seemed somehow to be -regarded as remarkable; they had evidently lost the power of doing and -saying commonplace things; moreover, their past history was raked up -and discovered to bear marks of conspicuous originality. The village -paper published biographical sketches of the boys. - -The Widow Douglas put Huck's money out at six per cent., and Judge -Thatcher did the same with Tom's at Aunt Polly's request. Each lad had -an income, now, that was simply prodigious--a dollar for every week-day -in the year and half of the Sundays. It was just what the minister got ---no, it was what he was promised--he generally couldn't collect it. A -dollar and a quarter a week would board, lodge, and school a boy in -those old simple days--and clothe him and wash him, too, for that -matter. - -Judge Thatcher had conceived a great opinion of Tom. He said that no -commonplace boy would ever have got his daughter out of the cave. When -Becky told her father, in strict confidence, how Tom had taken her -whipping at school, the Judge was visibly moved; and when she pleaded -grace for the mighty lie which Tom had told in order to shift that -whipping from her shoulders to his own, the Judge said with a fine -outburst that it was a noble, a generous, a magnanimous lie--a lie that -was worthy to hold up its head and march down through history breast to -breast with George Washington's lauded Truth about the hatchet! Becky -thought her father had never looked so tall and so superb as when he -walked the floor and stamped his foot and said that. She went straight -off and told Tom about it. - -Judge Thatcher hoped to see Tom a great lawyer or a great soldier some -day. He said he meant to look to it that Tom should be admitted to the -National Military Academy and afterward trained in the best law school -in the country, in order that he might be ready for either career or -both. - -Huck Finn's wealth and the fact that he was now under the Widow -Douglas' protection introduced him into society--no, dragged him into -it, hurled him into it--and his sufferings were almost more than he -could bear. The widow's servants kept him clean and neat, combed and -brushed, and they bedded him nightly in unsympathetic sheets that had -not one little spot or stain which he could press to his heart and know -for a friend. He had to eat with a knife and fork; he had to use -napkin, cup, and plate; he had to learn his book, he had to go to -church; he had to talk so properly that speech was become insipid in -his mouth; whithersoever he turned, the bars and shackles of -civilization shut him in and bound him hand and foot. - -He bravely bore his miseries three weeks, and then one day turned up -missing. For forty-eight hours the widow hunted for him everywhere in -great distress. The public were profoundly concerned; they searched -high and low, they dragged the river for his body. Early the third -morning Tom Sawyer wisely went poking among some old empty hogsheads -down behind the abandoned slaughter-house, and in one of them he found -the refugee. Huck had slept there; he had just breakfasted upon some -stolen odds and ends of food, and was lying off, now, in comfort, with -his pipe. He was unkempt, uncombed, and clad in the same old ruin of -rags that had made him picturesque in the days when he was free and -happy. Tom routed him out, told him the trouble he had been causing, -and urged him to go home. Huck's face lost its tranquil content, and -took a melancholy cast. He said: - -"Don't talk about it, Tom. I've tried it, and it don't work; it don't -work, Tom. It ain't for me; I ain't used to it. The widder's good to -me, and friendly; but I can't stand them ways. She makes me get up just -at the same time every morning; she makes me wash, they comb me all to -thunder; she won't let me sleep in the woodshed; I got to wear them -blamed clothes that just smothers me, Tom; they don't seem to any air -git through 'em, somehow; and they're so rotten nice that I can't set -down, nor lay down, nor roll around anywher's; I hain't slid on a -cellar-door for--well, it 'pears to be years; I got to go to church and -sweat and sweat--I hate them ornery sermons! I can't ketch a fly in -there, I can't chaw. I got to wear shoes all Sunday. The widder eats by -a bell; she goes to bed by a bell; she gits up by a bell--everything's -so awful reg'lar a body can't stand it." - -"Well, everybody does that way, Huck." - -"Tom, it don't make no difference. I ain't everybody, and I can't -STAND it. It's awful to be tied up so. And grub comes too easy--I don't -take no interest in vittles, that way. I got to ask to go a-fishing; I -got to ask to go in a-swimming--dern'd if I hain't got to ask to do -everything. Well, I'd got to talk so nice it wasn't no comfort--I'd got -to go up in the attic and rip out awhile, every day, to git a taste in -my mouth, or I'd a died, Tom. The widder wouldn't let me smoke; she -wouldn't let me yell, she wouldn't let me gape, nor stretch, nor -scratch, before folks--" [Then with a spasm of special irritation and -injury]--"And dad fetch it, she prayed all the time! I never see such a -woman! I HAD to shove, Tom--I just had to. And besides, that school's -going to open, and I'd a had to go to it--well, I wouldn't stand THAT, -Tom. Looky here, Tom, being rich ain't what it's cracked up to be. It's -just worry and worry, and sweat and sweat, and a-wishing you was dead -all the time. Now these clothes suits me, and this bar'l suits me, and -I ain't ever going to shake 'em any more. Tom, I wouldn't ever got into -all this trouble if it hadn't 'a' ben for that money; now you just take -my sheer of it along with your'n, and gimme a ten-center sometimes--not -many times, becuz I don't give a dern for a thing 'thout it's tollable -hard to git--and you go and beg off for me with the widder." - -"Oh, Huck, you know I can't do that. 'Tain't fair; and besides if -you'll try this thing just a while longer you'll come to like it." - -"Like it! Yes--the way I'd like a hot stove if I was to set on it long -enough. No, Tom, I won't be rich, and I won't live in them cussed -smothery houses. I like the woods, and the river, and hogsheads, and -I'll stick to 'em, too. Blame it all! just as we'd got guns, and a -cave, and all just fixed to rob, here this dern foolishness has got to -come up and spile it all!" - -Tom saw his opportunity-- - -"Lookyhere, Huck, being rich ain't going to keep me back from turning -robber." - -"No! Oh, good-licks; are you in real dead-wood earnest, Tom?" - -"Just as dead earnest as I'm sitting here. But Huck, we can't let you -into the gang if you ain't respectable, you know." - -Huck's joy was quenched. - -"Can't let me in, Tom? Didn't you let me go for a pirate?" - -"Yes, but that's different. A robber is more high-toned than what a -pirate is--as a general thing. In most countries they're awful high up -in the nobility--dukes and such." - -"Now, Tom, hain't you always ben friendly to me? You wouldn't shet me -out, would you, Tom? You wouldn't do that, now, WOULD you, Tom?" - -"Huck, I wouldn't want to, and I DON'T want to--but what would people -say? Why, they'd say, 'Mph! Tom Sawyer's Gang! pretty low characters in -it!' They'd mean you, Huck. You wouldn't like that, and I wouldn't." - -Huck was silent for some time, engaged in a mental struggle. Finally -he said: - -"Well, I'll go back to the widder for a month and tackle it and see if -I can come to stand it, if you'll let me b'long to the gang, Tom." - -"All right, Huck, it's a whiz! Come along, old chap, and I'll ask the -widow to let up on you a little, Huck." - -"Will you, Tom--now will you? That's good. If she'll let up on some of -the roughest things, I'll smoke private and cuss private, and crowd -through or bust. When you going to start the gang and turn robbers?" - -"Oh, right off. We'll get the boys together and have the initiation -to-night, maybe." - -"Have the which?" - -"Have the initiation." - -"What's that?" - -"It's to swear to stand by one another, and never tell the gang's -secrets, even if you're chopped all to flinders, and kill anybody and -all his family that hurts one of the gang." - -"That's gay--that's mighty gay, Tom, I tell you." - -"Well, I bet it is. And all that swearing's got to be done at -midnight, in the lonesomest, awfulest place you can find--a ha'nted -house is the best, but they're all ripped up now." - -"Well, midnight's good, anyway, Tom." - -"Yes, so it is. And you've got to swear on a coffin, and sign it with -blood." - -"Now, that's something LIKE! Why, it's a million times bullier than -pirating. I'll stick to the widder till I rot, Tom; and if I git to be -a reg'lar ripper of a robber, and everybody talking 'bout it, I reckon -she'll be proud she snaked me in out of the wet." - - - -CONCLUSION - -SO endeth this chronicle. It being strictly a history of a BOY, it -must stop here; the story could not go much further without becoming -the history of a MAN. When one writes a novel about grown people, he -knows exactly where to stop--that is, with a marriage; but when he -writes of juveniles, he must stop where he best can. - -Most of the characters that perform in this book still live, and are -prosperous and happy. Some day it may seem worth while to take up the -story of the younger ones again and see what sort of men and women they -turned out to be; therefore it will be wisest not to reveal any of that -part of their lives at present. diff --git a/src/compress/zlib/writer.go b/src/compress/zlib/writer.go index a7b219467e..9986e3834d 100644 --- a/src/compress/zlib/writer.go +++ b/src/compress/zlib/writer.go @@ -6,6 +6,7 @@ package zlib import ( "compress/flate" + "encoding/binary" "fmt" "hash" "hash/adler32" @@ -120,11 +121,7 @@ func (z *Writer) writeHeader() (err error) { } if z.dict != nil { // The next four bytes are the Adler-32 checksum of the dictionary. - checksum := adler32.Checksum(z.dict) - z.scratch[0] = uint8(checksum >> 24) - z.scratch[1] = uint8(checksum >> 16) - z.scratch[2] = uint8(checksum >> 8) - z.scratch[3] = uint8(checksum >> 0) + binary.BigEndian.PutUint32(z.scratch[:], adler32.Checksum(z.dict)) if _, err = z.w.Write(z.scratch[0:4]); err != nil { return err } @@ -190,10 +187,7 @@ func (z *Writer) Close() error { } checksum := z.digest.Sum32() // ZLIB (RFC 1950) is big-endian, unlike GZIP (RFC 1952). - z.scratch[0] = uint8(checksum >> 24) - z.scratch[1] = uint8(checksum >> 16) - z.scratch[2] = uint8(checksum >> 8) - z.scratch[3] = uint8(checksum >> 0) + binary.BigEndian.PutUint32(z.scratch[:], checksum) _, z.err = z.w.Write(z.scratch[0:4]) return z.err } diff --git a/src/context/context.go b/src/context/context.go index 85f8acf8fa..21a40d5947 100644 --- a/src/context/context.go +++ b/src/context/context.go @@ -393,7 +393,7 @@ func WithDeadline(parent Context, d time.Time) (Context, CancelFunc) { dur := time.Until(d) if dur <= 0 { c.cancel(true, DeadlineExceeded) // deadline has already passed - return c, func() { c.cancel(true, Canceled) } + return c, func() { c.cancel(false, Canceled) } } c.mu.Lock() defer c.mu.Unlock() diff --git a/src/crypto/cipher/benchmark_test.go b/src/crypto/cipher/benchmark_test.go index 1a3f1bdfac..90d0cd7138 100644 --- a/src/crypto/cipher/benchmark_test.go +++ b/src/crypto/cipher/benchmark_test.go @@ -81,70 +81,49 @@ func BenchmarkAESGCMOpen8K(b *testing.B) { benchmarkAESGCMOpen(b, make([]byte, 8*1024)) } -// If we test exactly 1K blocks, we would generate exact multiples of -// the cipher's block size, and the cipher stream fragments would -// always be wordsize aligned, whereas non-aligned is a more typical -// use-case. -const almost1K = 1024 - 5 - -func BenchmarkAESCFBEncrypt1K(b *testing.B) { - buf := make([]byte, almost1K) +func benchmarkAESStream(b *testing.B, mode func(cipher.Block, []byte) cipher.Stream, buf []byte) { b.SetBytes(int64(len(buf))) var key [16]byte var iv [16]byte aes, _ := aes.NewCipher(key[:]) - ctr := cipher.NewCFBEncrypter(aes, iv[:]) + stream := mode(aes, iv[:]) b.ResetTimer() for i := 0; i < b.N; i++ { - ctr.XORKeyStream(buf, buf) + stream.XORKeyStream(buf, buf) } } -func BenchmarkAESCFBDecrypt1K(b *testing.B) { - buf := make([]byte, almost1K) - b.SetBytes(int64(len(buf))) - - var key [16]byte - var iv [16]byte - aes, _ := aes.NewCipher(key[:]) - ctr := cipher.NewCFBDecrypter(aes, iv[:]) +// If we test exactly 1K blocks, we would generate exact multiples of +// the cipher's block size, and the cipher stream fragments would +// always be wordsize aligned, whereas non-aligned is a more typical +// use-case. +const almost1K = 1024 - 5 +const almost8K = 8*1024 - 5 - b.ResetTimer() - for i := 0; i < b.N; i++ { - ctr.XORKeyStream(buf, buf) - } +func BenchmarkAESCFBEncrypt1K(b *testing.B) { + benchmarkAESStream(b, cipher.NewCFBEncrypter, make([]byte, almost1K)) } -func BenchmarkAESOFB1K(b *testing.B) { - buf := make([]byte, almost1K) - b.SetBytes(int64(len(buf))) +func BenchmarkAESCFBDecrypt1K(b *testing.B) { + benchmarkAESStream(b, cipher.NewCFBDecrypter, make([]byte, almost1K)) +} - var key [16]byte - var iv [16]byte - aes, _ := aes.NewCipher(key[:]) - ctr := cipher.NewOFB(aes, iv[:]) +func BenchmarkAESCFBDecrypt8K(b *testing.B) { + benchmarkAESStream(b, cipher.NewCFBDecrypter, make([]byte, almost8K)) +} - b.ResetTimer() - for i := 0; i < b.N; i++ { - ctr.XORKeyStream(buf, buf) - } +func BenchmarkAESOFB1K(b *testing.B) { + benchmarkAESStream(b, cipher.NewOFB, make([]byte, almost1K)) } func BenchmarkAESCTR1K(b *testing.B) { - buf := make([]byte, almost1K) - b.SetBytes(int64(len(buf))) - - var key [16]byte - var iv [16]byte - aes, _ := aes.NewCipher(key[:]) - ctr := cipher.NewCTR(aes, iv[:]) + benchmarkAESStream(b, cipher.NewCTR, make([]byte, almost1K)) +} - b.ResetTimer() - for i := 0; i < b.N; i++ { - ctr.XORKeyStream(buf, buf) - } +func BenchmarkAESCTR8K(b *testing.B) { + benchmarkAESStream(b, cipher.NewCTR, make([]byte, almost8K)) } func BenchmarkAESCBCEncrypt1K(b *testing.B) { diff --git a/src/crypto/md5/md5block_386.s b/src/crypto/md5/md5block_386.s index 8e426d148f..30d4209a62 100644 --- a/src/crypto/md5/md5block_386.s +++ b/src/crypto/md5/md5block_386.s @@ -122,7 +122,7 @@ loop: ROUND2(DX,AX,BX,CX, 7,0xfcefa3f8, 9); ROUND2(CX,DX,AX,BX,12,0x676f02d9,14); ROUND2(BX,CX,DX,AX, 0,0x8d2a4c8a,20); - + MOVL (5*4)(SI), DI MOVL CX, BP diff --git a/src/crypto/md5/md5block_amd64.s b/src/crypto/md5/md5block_amd64.s index a3ae7d97b2..90d932b146 100644 --- a/src/crypto/md5/md5block_amd64.s +++ b/src/crypto/md5/md5block_amd64.s @@ -99,7 +99,7 @@ loop: ROUND2(DX,AX,BX,CX, 7,0xfcefa3f8, 9); ROUND2(CX,DX,AX,BX,12,0x676f02d9,14); ROUND2(BX,CX,DX,AX, 0,0x8d2a4c8a,20); - + MOVL (5*4)(SI), R8 MOVL CX, R9 @@ -144,7 +144,7 @@ loop: ROLL $shift, a; \ XORL c, R9; \ ADDL b, a - + ROUND4(AX,BX,CX,DX, 7,0xf4292244, 6); ROUND4(DX,AX,BX,CX,14,0x432aff97,10); ROUND4(CX,DX,AX,BX, 5,0xab9423a7,15); diff --git a/src/crypto/md5/md5block_amd64p32.s b/src/crypto/md5/md5block_amd64p32.s index ee05f8613b..7295942dc8 100644 --- a/src/crypto/md5/md5block_amd64p32.s +++ b/src/crypto/md5/md5block_amd64p32.s @@ -103,7 +103,7 @@ loop: ROUND2(DX,AX,BX,CX, 7,0xfcefa3f8, 9); ROUND2(CX,DX,AX,BX,12,0x676f02d9,14); ROUND2(BX,CX,DX,AX, 0,0x8d2a4c8a,20); - + MOVL (5*4)(SI), R8 MOVL CX, R9 @@ -148,7 +148,7 @@ loop: ROLL $shift, a; \ XORL c, R9; \ ADDL b, a - + ROUND4(AX,BX,CX,DX, 7,0xf4292244, 6); ROUND4(DX,AX,BX,CX,14,0x432aff97,10); ROUND4(CX,DX,AX,BX, 5,0xab9423a7,15); diff --git a/src/crypto/rand/rand.go b/src/crypto/rand/rand.go index 952d20aa16..a5ccd19de3 100644 --- a/src/crypto/rand/rand.go +++ b/src/crypto/rand/rand.go @@ -23,3 +23,7 @@ var Reader io.Reader func Read(b []byte) (n int, err error) { return io.ReadFull(Reader, b) } + +func warnBlocked() { + println("crypto/rand: blocked for 60 seconds waiting to read random data from the kernel") +} diff --git a/src/crypto/rand/rand_unix.go b/src/crypto/rand/rand_unix.go index 13c874a961..272b83d52b 100644 --- a/src/crypto/rand/rand_unix.go +++ b/src/crypto/rand/rand_unix.go @@ -19,6 +19,7 @@ import ( "os" "runtime" "sync" + "sync/atomic" "time" ) @@ -44,6 +45,7 @@ type devReader struct { name string f io.Reader mu sync.Mutex + used int32 // atomic; whether this devReader has been used } // altGetRandom if non-nil specifies an OS-specific function to get @@ -52,6 +54,12 @@ var altGetRandom func([]byte) (ok bool) func (r *devReader) Read(b []byte) (n int, err error) { boring.Unreachable() + if atomic.CompareAndSwapInt32(&r.used, 0, 1) { + // First use of randomness. Start timer to warn about + // being blocked on entropy not being available. + t := time.AfterFunc(60*time.Second, warnBlocked) + defer t.Stop() + } if altGetRandom != nil && r.name == urandomDevice && altGetRandom(b) { return len(b), nil } diff --git a/src/crypto/rand/rand_windows.go b/src/crypto/rand/rand_windows.go index 4d7511a840..78a4ed6d67 100644 --- a/src/crypto/rand/rand_windows.go +++ b/src/crypto/rand/rand_windows.go @@ -10,7 +10,9 @@ package rand import ( "os" "sync" + "sync/atomic" "syscall" + "time" ) // Implemented by using Windows CryptoAPI 2.0. @@ -19,11 +21,18 @@ func init() { Reader = &rngReader{} } // A rngReader satisfies reads by reading from the Windows CryptGenRandom API. type rngReader struct { + used int32 // atomic; whether this rngReader has been used prov syscall.Handle mu sync.Mutex } func (r *rngReader) Read(b []byte) (n int, err error) { + if atomic.CompareAndSwapInt32(&r.used, 0, 1) { + // First use of randomness. Start timer to warn about + // being blocked on entropy not being available. + t := time.AfterFunc(60*time.Second, warnBlocked) + defer t.Stop() + } r.mu.Lock() if r.prov == 0 { const provType = syscall.PROV_RSA_FULL diff --git a/src/crypto/rsa/pss_test.go b/src/crypto/rsa/pss_test.go index 4ce5ad8684..32f6f0c3aa 100644 --- a/src/crypto/rsa/pss_test.go +++ b/src/crypto/rsa/pss_test.go @@ -102,7 +102,7 @@ func TestPSSGolden(t *testing.T) { switch { case len(line) == 0: if len(partialValue) > 0 { - values <- strings.Replace(partialValue, " ", "", -1) + values <- strings.ReplaceAll(partialValue, " ", "") partialValue = "" lastWasValue = true } diff --git a/src/crypto/sha1/sha1block_386.s b/src/crypto/sha1/sha1block_386.s index 0a7e45a79c..34d023d424 100644 --- a/src/crypto/sha1/sha1block_386.s +++ b/src/crypto/sha1/sha1block_386.s @@ -105,7 +105,7 @@ TEXT ·block(SB),NOSPLIT,$92-16 MOVL p_len+8(FP), DX SHRL $6, DX SHLL $6, DX - + LEAL (SI)(DX*1), DI MOVL (0*4)(BP), AX MOVL (1*4)(BP), BX @@ -148,7 +148,7 @@ loop: ROUND1x(DX, BP, AX, BX, CX, 17) ROUND1x(CX, DX, BP, AX, BX, 18) ROUND1x(BX, CX, DX, BP, AX, 19) - + ROUND2(AX, BX, CX, DX, BP, 20) ROUND2(BP, AX, BX, CX, DX, 21) ROUND2(DX, BP, AX, BX, CX, 22) @@ -169,7 +169,7 @@ loop: ROUND2(DX, BP, AX, BX, CX, 37) ROUND2(CX, DX, BP, AX, BX, 38) ROUND2(BX, CX, DX, BP, AX, 39) - + ROUND3(AX, BX, CX, DX, BP, 40) ROUND3(BP, AX, BX, CX, DX, 41) ROUND3(DX, BP, AX, BX, CX, 42) @@ -190,7 +190,7 @@ loop: ROUND3(DX, BP, AX, BX, CX, 57) ROUND3(CX, DX, BP, AX, BX, 58) ROUND3(BX, CX, DX, BP, AX, 59) - + ROUND4(AX, BX, CX, DX, BP, 60) ROUND4(BP, AX, BX, CX, DX, 61) ROUND4(DX, BP, AX, BX, CX, 62) diff --git a/src/crypto/sha1/sha1block_amd64.s b/src/crypto/sha1/sha1block_amd64.s index 135f113898..42f03fb268 100644 --- a/src/crypto/sha1/sha1block_amd64.s +++ b/src/crypto/sha1/sha1block_amd64.s @@ -60,7 +60,7 @@ MOVL b, R9; \ ANDL c, R9; \ ORL R8, R9 - + #define FUNC4 FUNC2 #define MIX(a, b, c, d, e, const) \ @@ -102,7 +102,7 @@ TEXT ·blockAMD64(SB),NOSPLIT,$64-32 MOVQ p_len+16(FP), DX SHRQ $6, DX SHLQ $6, DX - + LEAQ (SI)(DX*1), DI MOVL (0*4)(BP), AX MOVL (1*4)(BP), BX @@ -141,7 +141,7 @@ loop: ROUND1x(DX, BP, AX, BX, CX, 17) ROUND1x(CX, DX, BP, AX, BX, 18) ROUND1x(BX, CX, DX, BP, AX, 19) - + ROUND2(AX, BX, CX, DX, BP, 20) ROUND2(BP, AX, BX, CX, DX, 21) ROUND2(DX, BP, AX, BX, CX, 22) @@ -162,7 +162,7 @@ loop: ROUND2(DX, BP, AX, BX, CX, 37) ROUND2(CX, DX, BP, AX, BX, 38) ROUND2(BX, CX, DX, BP, AX, 39) - + ROUND3(AX, BX, CX, DX, BP, 40) ROUND3(BP, AX, BX, CX, DX, 41) ROUND3(DX, BP, AX, BX, CX, 42) @@ -183,7 +183,7 @@ loop: ROUND3(DX, BP, AX, BX, CX, 57) ROUND3(CX, DX, BP, AX, BX, 58) ROUND3(BX, CX, DX, BP, AX, 59) - + ROUND4(AX, BX, CX, DX, BP, 60) ROUND4(BP, AX, BX, CX, DX, 61) ROUND4(DX, BP, AX, BX, CX, 62) diff --git a/src/crypto/sha1/sha1block_amd64p32.s b/src/crypto/sha1/sha1block_amd64p32.s index e5404e8997..32058ba01d 100644 --- a/src/crypto/sha1/sha1block_amd64p32.s +++ b/src/crypto/sha1/sha1block_amd64p32.s @@ -55,7 +55,7 @@ MOVL b, R9; \ ANDL c, R9; \ ORL R8, R9 - + #define FUNC4 FUNC2 #define MIX(a, b, c, d, e, const) \ @@ -97,7 +97,7 @@ TEXT ·block(SB),NOSPLIT,$64-16 MOVL p_len+8(FP), DX SHRQ $6, DX SHLQ $6, DX - + LEAQ (SI)(DX*1), DI MOVL (0*4)(R14), AX MOVL (1*4)(R14), BX @@ -131,7 +131,7 @@ loop: ROUND1x(DX, BP, AX, BX, CX, 17) ROUND1x(CX, DX, BP, AX, BX, 18) ROUND1x(BX, CX, DX, BP, AX, 19) - + ROUND2(AX, BX, CX, DX, BP, 20) ROUND2(BP, AX, BX, CX, DX, 21) ROUND2(DX, BP, AX, BX, CX, 22) @@ -152,7 +152,7 @@ loop: ROUND2(DX, BP, AX, BX, CX, 37) ROUND2(CX, DX, BP, AX, BX, 38) ROUND2(BX, CX, DX, BP, AX, 39) - + ROUND3(AX, BX, CX, DX, BP, 40) ROUND3(BP, AX, BX, CX, DX, 41) ROUND3(DX, BP, AX, BX, CX, 42) @@ -173,7 +173,7 @@ loop: ROUND3(DX, BP, AX, BX, CX, 57) ROUND3(CX, DX, BP, AX, BX, 58) ROUND3(BX, CX, DX, BP, AX, 59) - + ROUND4(AX, BX, CX, DX, BP, 60) ROUND4(BP, AX, BX, CX, DX, 61) ROUND4(DX, BP, AX, BX, CX, 62) diff --git a/src/crypto/sha1/sha1block_arm.s b/src/crypto/sha1/sha1block_arm.s index 055edc9f3f..2236533ab4 100644 --- a/src/crypto/sha1/sha1block_arm.s +++ b/src/crypto/sha1/sha1block_arm.s @@ -63,10 +63,10 @@ ORR Rt1<<24, Rt0, Rt0 ; \ MOVW.P Rt0, 4(Rw) ; \ ADD Rt0, Re, Re - + // tmp := w[(i-3)&0xf] ^ w[(i-8)&0xf] ^ w[(i-14)&0xf] ^ w[(i)&0xf] // w[i&0xf] = tmp<<1 | tmp>>(32-1) - // e += w[i&0xf] + // e += w[i&0xf] #define SHUFFLE(Re) \ MOVW (-16*4)(Rw), Rt0 ; \ MOVW (-14*4)(Rw), Rt1 ; \ @@ -167,7 +167,7 @@ loop1: ROUND1(Ra, Rb, Rc, Rd, Re) ROUND1x(Rd, Re, Ra, Rb, Rc) ROUND1x(Rc, Rd, Re, Ra, Rb) ROUND1x(Rb, Rc, Rd, Re, Ra) - + MOVW $0x6ED9EBA1, Rconst MOVW $4, Rctr loop2: ROUND2(Ra, Rb, Rc, Rd, Re) @@ -177,7 +177,7 @@ loop2: ROUND2(Ra, Rb, Rc, Rd, Re) ROUND2(Rb, Rc, Rd, Re, Ra) SUB.S $1, Rctr BNE loop2 - + MOVW $0x8F1BBCDC, Rconst MOVW $4, Rctr loop3: ROUND3(Ra, Rb, Rc, Rd, Re) @@ -187,7 +187,7 @@ loop3: ROUND3(Ra, Rb, Rc, Rd, Re) ROUND3(Rb, Rc, Rd, Re, Ra) SUB.S $1, Rctr BNE loop3 - + MOVW $0xCA62C1D6, Rconst MOVW $4, Rctr loop4: ROUND4(Ra, Rb, Rc, Rd, Re) diff --git a/src/crypto/x509/cert_pool.go b/src/crypto/x509/cert_pool.go index 86aba6710d..7cc1dd4eb6 100644 --- a/src/crypto/x509/cert_pool.go +++ b/src/crypto/x509/cert_pool.go @@ -50,7 +50,7 @@ func (s *CertPool) copy() *CertPool { // Any mutations to the returned pool are not written to disk and do // not affect any other pool returned by SystemCertPool. // -// New changes in the the system cert pool might not be reflected +// New changes in the system cert pool might not be reflected // in subsequent calls. func SystemCertPool() (*CertPool, error) { if runtime.GOOS == "windows" { diff --git a/src/crypto/x509/root_darwin_arm_gen.go b/src/crypto/x509/root_darwin_arm_gen.go index b5580d6f02..bc44124a78 100644 --- a/src/crypto/x509/root_darwin_arm_gen.go +++ b/src/crypto/x509/root_darwin_arm_gen.go @@ -154,9 +154,9 @@ func fetchCertIDs() ([]certID, error) { values := regexp.MustCompile("(?s)<td>(.*?)</td>").FindAllStringSubmatch(row, -1) name := values[cols["Certificate name"]][1] fingerprint := values[cols["Fingerprint (SHA-256)"]][1] - fingerprint = strings.Replace(fingerprint, "<br>", "", -1) - fingerprint = strings.Replace(fingerprint, "\n", "", -1) - fingerprint = strings.Replace(fingerprint, " ", "", -1) + fingerprint = strings.ReplaceAll(fingerprint, "<br>", "") + fingerprint = strings.ReplaceAll(fingerprint, "\n", "") + fingerprint = strings.ReplaceAll(fingerprint, " ", "") fingerprint = strings.ToLower(fingerprint) ids = append(ids, certID{ diff --git a/src/crypto/x509/verify.go b/src/crypto/x509/verify.go index 94b68a4607..b545f2b2dc 100644 --- a/src/crypto/x509/verify.go +++ b/src/crypto/x509/verify.go @@ -906,8 +906,8 @@ func validHostname(host string) bool { if c == '-' && j != 0 { continue } - if c == '_' { - // _ is not a valid character in hostnames, but it's commonly + if c == '_' || c == ':' { + // Not valid characters in hostnames, but commonly // found in deployments outside the WebPKI. continue } diff --git a/src/crypto/x509/verify_test.go b/src/crypto/x509/verify_test.go index 7684145839..0e24d3b5da 100644 --- a/src/crypto/x509/verify_test.go +++ b/src/crypto/x509/verify_test.go @@ -1881,6 +1881,7 @@ func TestValidHostname(t *testing.T) { {"foo.*.example.com", false}, {"exa_mple.com", true}, {"foo,bar", false}, + {"project-dev:us-central1:main", true}, } for _, tt := range tests { if got := validHostname(tt.host); got != tt.want { diff --git a/src/database/sql/driver/driver.go b/src/database/sql/driver/driver.go index 1e54b4cf2c..70b3ddc470 100644 --- a/src/database/sql/driver/driver.go +++ b/src/database/sql/driver/driver.go @@ -469,7 +469,7 @@ type RowsAffected int64 var _ Result = RowsAffected(0) func (RowsAffected) LastInsertId() (int64, error) { - return 0, errors.New("no LastInsertId available") + return 0, errors.New("LastInsertId is not supported by this driver") } func (v RowsAffected) RowsAffected() (int64, error) { diff --git a/src/database/sql/sql.go b/src/database/sql/sql.go index 7537f87d47..7c8d46b100 100644 --- a/src/database/sql/sql.go +++ b/src/database/sql/sql.go @@ -1322,11 +1322,13 @@ func (db *DB) putConnDBLocked(dc *driverConn, err error) bool { err: err, } return true - } else if err == nil && !db.closed && db.maxIdleConnsLocked() > len(db.freeConn) { - db.freeConn = append(db.freeConn, dc) + } else if err == nil && !db.closed { + if db.maxIdleConnsLocked() > len(db.freeConn) { + db.freeConn = append(db.freeConn, dc) + db.startCleanerLocked() + return true + } db.maxIdleClosed++ - db.startCleanerLocked() - return true } return false } diff --git a/src/database/sql/sql_test.go b/src/database/sql/sql_test.go index f194744aef..e52091c3af 100644 --- a/src/database/sql/sql_test.go +++ b/src/database/sql/sql_test.go @@ -3415,6 +3415,58 @@ func TestConnectionLeak(t *testing.T) { wg.Wait() } +func TestStatsMaxIdleClosedZero(t *testing.T) { + db := newTestDB(t, "people") + defer closeDB(t, db) + + db.SetMaxOpenConns(1) + db.SetMaxIdleConns(1) + db.SetConnMaxLifetime(0) + + preMaxIdleClosed := db.Stats().MaxIdleClosed + + for i := 0; i < 10; i++ { + rows, err := db.Query("SELECT|people|name|") + if err != nil { + t.Fatal(err) + } + rows.Close() + } + + st := db.Stats() + maxIdleClosed := st.MaxIdleClosed - preMaxIdleClosed + t.Logf("MaxIdleClosed: %d", maxIdleClosed) + if maxIdleClosed != 0 { + t.Fatal("expected 0 max idle closed conns, got: ", maxIdleClosed) + } +} + +func TestStatsMaxIdleClosedTen(t *testing.T) { + db := newTestDB(t, "people") + defer closeDB(t, db) + + db.SetMaxOpenConns(1) + db.SetMaxIdleConns(0) + db.SetConnMaxLifetime(0) + + preMaxIdleClosed := db.Stats().MaxIdleClosed + + for i := 0; i < 10; i++ { + rows, err := db.Query("SELECT|people|name|") + if err != nil { + t.Fatal(err) + } + rows.Close() + } + + st := db.Stats() + maxIdleClosed := st.MaxIdleClosed - preMaxIdleClosed + t.Logf("MaxIdleClosed: %d", maxIdleClosed) + if maxIdleClosed != 10 { + t.Fatal("expected 0 max idle closed conns, got: ", maxIdleClosed) + } +} + type nvcDriver struct { fakeDriver skipNamedValueCheck bool diff --git a/src/debug/elf/elf.go b/src/debug/elf/elf.go index 07c03e7999..96a67ce732 100644 --- a/src/debug/elf/elf.go +++ b/src/debug/elf/elf.go @@ -2424,6 +2424,7 @@ const ( R_RISCV_SET8 R_RISCV = 54 /* Local label subtraction */ R_RISCV_SET16 R_RISCV = 55 /* Local label subtraction */ R_RISCV_SET32 R_RISCV = 56 /* Local label subtraction */ + R_RISCV_32_PCREL R_RISCV = 57 /* 32-bit PC relative */ ) var rriscvStrings = []intName{ @@ -2480,6 +2481,7 @@ var rriscvStrings = []intName{ {54, "R_RISCV_SET8"}, {55, "R_RISCV_SET16"}, {56, "R_RISCV_SET32"}, + {57, "R_RISCV_32_PCREL"}, } func (i R_RISCV) String() string { return stringName(uint32(i), rriscvStrings, false) } diff --git a/src/encoding/base32/base32_test.go b/src/encoding/base32/base32_test.go index c5506ed4de..b74054ba40 100644 --- a/src/encoding/base32/base32_test.go +++ b/src/encoding/base32/base32_test.go @@ -425,7 +425,7 @@ IZJAOZSWY2LUEBSXG43FEBRWS3DMOVWSAZDPNRXXEZJAMV2SAZTVM5UWC5BANZ2WY3DBBJYGC4TJMF NZ2CYIDTOVXHIIDJNYFGG5LMOBQSA4LVNEQG6ZTGNFRWSYJAMRSXGZLSOVXHIIDNN5WGY2LUEBQW42 LNEBUWIIDFON2CA3DBMJXXE5LNFY== ====` - encodedShort := strings.Replace(encoded, "\n", "", -1) + encodedShort := strings.ReplaceAll(encoded, "\n", "") dec := NewDecoder(StdEncoding, strings.NewReader(encoded)) res1, err := ioutil.ReadAll(dec) @@ -465,7 +465,7 @@ func TestWithCustomPadding(t *testing.T) { for _, testcase := range pairs { defaultPadding := StdEncoding.EncodeToString([]byte(testcase.decoded)) customPadding := StdEncoding.WithPadding('@').EncodeToString([]byte(testcase.decoded)) - expected := strings.Replace(defaultPadding, "=", "@", -1) + expected := strings.ReplaceAll(defaultPadding, "=", "@") if expected != customPadding { t.Errorf("Expected custom %s, got %s", expected, customPadding) @@ -675,7 +675,7 @@ func TestWithoutPaddingClose(t *testing.T) { expected := testpair.encoded if encoding.padChar == NoPadding { - expected = strings.Replace(expected, "=", "", -1) + expected = strings.ReplaceAll(expected, "=", "") } res := buf.String() @@ -697,7 +697,7 @@ func TestDecodeReadAll(t *testing.T) { for encIndex, encoding := range encodings { encoded := pair.encoded if encoding.padChar == NoPadding { - encoded = strings.Replace(encoded, "=", "", -1) + encoded = strings.ReplaceAll(encoded, "=", "") } decReader, err := ioutil.ReadAll(NewDecoder(encoding, strings.NewReader(encoded))) @@ -723,7 +723,7 @@ func TestDecodeSmallBuffer(t *testing.T) { for encIndex, encoding := range encodings { encoded := pair.encoded if encoding.padChar == NoPadding { - encoded = strings.Replace(encoded, "=", "", -1) + encoded = strings.ReplaceAll(encoded, "=", "") } decoder := NewDecoder(encoding, strings.NewReader(encoded)) diff --git a/src/encoding/base64/base64_test.go b/src/encoding/base64/base64_test.go index f019654f5b..f7f312ca39 100644 --- a/src/encoding/base64/base64_test.go +++ b/src/encoding/base64/base64_test.go @@ -53,8 +53,8 @@ func stdRef(ref string) string { // Convert a reference string to URL-encoding func urlRef(ref string) string { - ref = strings.Replace(ref, "+", "-", -1) - ref = strings.Replace(ref, "/", "_", -1) + ref = strings.ReplaceAll(ref, "+", "-") + ref = strings.ReplaceAll(ref, "/", "_") return ref } @@ -72,7 +72,7 @@ func rawURLRef(ref string) string { var funnyEncoding = NewEncoding(encodeStd).WithPadding(rune('@')) func funnyRef(ref string) string { - return strings.Replace(ref, "=", "@", -1) + return strings.ReplaceAll(ref, "=", "@") } type encodingTest struct { @@ -418,7 +418,7 @@ j+mSARB/17pKVXYWHXjsj7yIex0PadzXMO1zT5KHoNA3HT8ietoGhgjsfA+CSnvvqh/jJtqsrwOv 2b6NGNzXfTYexzJ+nU7/ALkf4P8Awv6P9KvTQQ4AgyDqCF85Pho3CTB7eHwXoH+LT65uZbX9X+o2 bqbPb06551Y4 ` - encodedShort := strings.Replace(encoded, "\n", "", -1) + encodedShort := strings.ReplaceAll(encoded, "\n", "") dec := NewDecoder(StdEncoding, strings.NewReader(encoded)) res1, err := ioutil.ReadAll(dec) diff --git a/src/encoding/json/decode.go b/src/encoding/json/decode.go index 82dc78083a..cab4616ba3 100644 --- a/src/encoding/json/decode.go +++ b/src/encoding/json/decode.go @@ -11,7 +11,6 @@ import ( "bytes" "encoding" "encoding/base64" - "errors" "fmt" "reflect" "strconv" @@ -280,10 +279,10 @@ func (d *decodeState) readIndex() int { return d.off - 1 } -// errPhase is used for errors that should not happen unless -// there is a bug in the JSON decoder or something is editing -// the data slice while the decoder executes. -var errPhase = errors.New("JSON decoder out of sync - data changing underfoot?") +// phasePanicMsg is used as a panic message when we end up with something that +// shouldn't happen. It can indicate a bug in the JSON decoder, or that +// something is editing the data slice while the decoder executes. +const phasePanicMsg = "JSON decoder out of sync - data changing underfoot?" func (d *decodeState) init(data []byte) *decodeState { d.data = data @@ -365,7 +364,7 @@ func (d *decodeState) scanWhile(op int) { func (d *decodeState) value(v reflect.Value) error { switch d.opcode { default: - return errPhase + panic(phasePanicMsg) case scanBeginArray: if v.IsValid() { @@ -407,26 +406,23 @@ type unquotedValue struct{} // quoted string literal or literal null into an interface value. // If it finds anything other than a quoted string literal or null, // valueQuoted returns unquotedValue{}. -func (d *decodeState) valueQuoted() (interface{}, error) { +func (d *decodeState) valueQuoted() interface{} { switch d.opcode { default: - return nil, errPhase + panic(phasePanicMsg) case scanBeginArray, scanBeginObject: d.skip() d.scanNext() case scanBeginLiteral: - v, err := d.literalInterface() - if err != nil { - return nil, err - } + v := d.literalInterface() switch v.(type) { case nil, string: - return v, nil + return v } } - return unquotedValue{}, nil + return unquotedValue{} } // indirect walks down v allocating pointers as needed, @@ -520,10 +516,7 @@ func (d *decodeState) array(v reflect.Value) error { case reflect.Interface: if v.NumMethod() == 0 { // Decoding into nil interface? Switch to non-reflect code. - ai, err := d.arrayInterface() - if err != nil { - return err - } + ai := d.arrayInterface() v.Set(reflect.ValueOf(ai)) return nil } @@ -533,8 +526,7 @@ func (d *decodeState) array(v reflect.Value) error { d.saveError(&UnmarshalTypeError{Value: "array", Type: v.Type(), Offset: int64(d.off)}) d.skip() return nil - case reflect.Array: - case reflect.Slice: + case reflect.Array, reflect.Slice: break } @@ -584,7 +576,7 @@ func (d *decodeState) array(v reflect.Value) error { break } if d.opcode != scanArrayValue { - return errPhase + panic(phasePanicMsg) } } @@ -628,10 +620,7 @@ func (d *decodeState) object(v reflect.Value) error { // Decoding into nil interface? Switch to non-reflect code. if v.Kind() == reflect.Interface && v.NumMethod() == 0 { - oi, err := d.objectInterface() - if err != nil { - return err - } + oi := d.objectInterface() v.Set(reflect.ValueOf(oi)) return nil } @@ -680,7 +669,7 @@ func (d *decodeState) object(v reflect.Value) error { break } if d.opcode != scanBeginLiteral { - return errPhase + panic(phasePanicMsg) } // Read key. @@ -689,7 +678,7 @@ func (d *decodeState) object(v reflect.Value) error { item := d.data[start:d.readIndex()] key, ok := unquoteBytes(item) if !ok { - return errPhase + panic(phasePanicMsg) } // Figure out field corresponding to key. @@ -753,16 +742,12 @@ func (d *decodeState) object(v reflect.Value) error { d.scanWhile(scanSkipSpace) } if d.opcode != scanObjectKey { - return errPhase + panic(phasePanicMsg) } d.scanWhile(scanSkipSpace) if destring { - q, err := d.valueQuoted() - if err != nil { - return err - } - switch qv := q.(type) { + switch qv := d.valueQuoted().(type) { case nil: if err := d.literalStore(nullLiteral, subv, false); err != nil { return err @@ -827,7 +812,7 @@ func (d *decodeState) object(v reflect.Value) error { break } if d.opcode != scanObjectValue { - return errPhase + panic(phasePanicMsg) } d.errorContext = originalErrorContext @@ -871,18 +856,16 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value, fromQuoted bool if item[0] != '"' { if fromQuoted { d.saveError(fmt.Errorf("json: invalid use of ,string struct tag, trying to unmarshal %q into %v", item, v.Type())) - } else { - var val string - switch item[0] { - case 'n': - val = "null" - case 't', 'f': - val = "bool" - default: - val = "number" - } - d.saveError(&UnmarshalTypeError{Value: val, Type: v.Type(), Offset: int64(d.readIndex())}) + return nil + } + val := "number" + switch item[0] { + case 'n': + val = "null" + case 't', 'f': + val = "bool" } + d.saveError(&UnmarshalTypeError{Value: val, Type: v.Type(), Offset: int64(d.readIndex())}) return nil } s, ok := unquoteBytes(item) @@ -890,7 +873,7 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value, fromQuoted bool if fromQuoted { return fmt.Errorf("json: invalid use of ,string struct tag, trying to unmarshal %q into %v", item, v.Type()) } - return errPhase + panic(phasePanicMsg) } return ut.UnmarshalText(s) } @@ -941,7 +924,7 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value, fromQuoted bool if fromQuoted { return fmt.Errorf("json: invalid use of ,string struct tag, trying to unmarshal %q into %v", item, v.Type()) } - return errPhase + panic(phasePanicMsg) } switch v.Kind() { default: @@ -973,7 +956,7 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value, fromQuoted bool if fromQuoted { return fmt.Errorf("json: invalid use of ,string struct tag, trying to unmarshal %q into %v", item, v.Type()) } - return errPhase + panic(phasePanicMsg) } s := string(item) switch v.Kind() { @@ -1034,24 +1017,24 @@ func (d *decodeState) literalStore(item []byte, v reflect.Value, fromQuoted bool // but they avoid the weight of reflection in this common case. // valueInterface is like value but returns interface{} -func (d *decodeState) valueInterface() (val interface{}, err error) { +func (d *decodeState) valueInterface() (val interface{}) { switch d.opcode { default: - err = errPhase + panic(phasePanicMsg) case scanBeginArray: - val, err = d.arrayInterface() + val = d.arrayInterface() d.scanNext() case scanBeginObject: - val, err = d.objectInterface() + val = d.objectInterface() d.scanNext() case scanBeginLiteral: - val, err = d.literalInterface() + val = d.literalInterface() } return } // arrayInterface is like array but returns []interface{}. -func (d *decodeState) arrayInterface() ([]interface{}, error) { +func (d *decodeState) arrayInterface() []interface{} { var v = make([]interface{}, 0) for { // Look ahead for ] - can only happen on first iteration. @@ -1060,11 +1043,7 @@ func (d *decodeState) arrayInterface() ([]interface{}, error) { break } - vi, err := d.valueInterface() - if err != nil { - return nil, err - } - v = append(v, vi) + v = append(v, d.valueInterface()) // Next token must be , or ]. if d.opcode == scanSkipSpace { @@ -1074,14 +1053,14 @@ func (d *decodeState) arrayInterface() ([]interface{}, error) { break } if d.opcode != scanArrayValue { - return nil, errPhase + panic(phasePanicMsg) } } - return v, nil + return v } // objectInterface is like object but returns map[string]interface{}. -func (d *decodeState) objectInterface() (map[string]interface{}, error) { +func (d *decodeState) objectInterface() map[string]interface{} { m := make(map[string]interface{}) for { // Read opening " of string key or closing }. @@ -1091,7 +1070,7 @@ func (d *decodeState) objectInterface() (map[string]interface{}, error) { break } if d.opcode != scanBeginLiteral { - return nil, errPhase + panic(phasePanicMsg) } // Read string key. @@ -1100,7 +1079,7 @@ func (d *decodeState) objectInterface() (map[string]interface{}, error) { item := d.data[start:d.readIndex()] key, ok := unquote(item) if !ok { - return nil, errPhase + panic(phasePanicMsg) } // Read : before value. @@ -1108,16 +1087,12 @@ func (d *decodeState) objectInterface() (map[string]interface{}, error) { d.scanWhile(scanSkipSpace) } if d.opcode != scanObjectKey { - return nil, errPhase + panic(phasePanicMsg) } d.scanWhile(scanSkipSpace) // Read value. - vi, err := d.valueInterface() - if err != nil { - return nil, err - } - m[key] = vi + m[key] = d.valueInterface() // Next token must be , or }. if d.opcode == scanSkipSpace { @@ -1127,16 +1102,16 @@ func (d *decodeState) objectInterface() (map[string]interface{}, error) { break } if d.opcode != scanObjectValue { - return nil, errPhase + panic(phasePanicMsg) } } - return m, nil + return m } // literalInterface consumes and returns a literal from d.data[d.off-1:] and // it reads the following byte ahead. The first byte of the literal has been // read already (that's how the caller knows it's a literal). -func (d *decodeState) literalInterface() (interface{}, error) { +func (d *decodeState) literalInterface() interface{} { // All bytes inside literal return scanContinue op code. start := d.readIndex() d.scanWhile(scanContinue) @@ -1145,27 +1120,27 @@ func (d *decodeState) literalInterface() (interface{}, error) { switch c := item[0]; c { case 'n': // null - return nil, nil + return nil case 't', 'f': // true, false - return c == 't', nil + return c == 't' case '"': // string s, ok := unquote(item) if !ok { - return nil, errPhase + panic(phasePanicMsg) } - return s, nil + return s default: // number if c != '-' && (c < '0' || c > '9') { - return nil, errPhase + panic(phasePanicMsg) } n, err := d.convertNumber(string(item)) if err != nil { d.saveError(err) } - return n, nil + return n } } diff --git a/src/encoding/json/decode_test.go b/src/encoding/json/decode_test.go index defa97e40f..5fbe67a706 100644 --- a/src/encoding/json/decode_test.go +++ b/src/encoding/json/decode_test.go @@ -445,6 +445,7 @@ var unmarshalTests = []unmarshalTest{ {in: `{"X": "foo", "Y"}`, err: &SyntaxError{"invalid character '}' after object key", 17}}, {in: `[1, 2, 3+]`, err: &SyntaxError{"invalid character '+' after array element", 9}}, {in: `{"X":12x}`, err: &SyntaxError{"invalid character 'x' after object key:value pair", 8}, useNumber: true}, + {in: `[2, 3`, err: &SyntaxError{msg: "unexpected end of JSON input", Offset: 5}}, // raw value errors {in: "\x01 42", err: &SyntaxError{"invalid character '\\x01' looking for beginning of value", 1}}, @@ -460,6 +461,7 @@ var unmarshalTests = []unmarshalTest{ {in: `[1, 2, 3]`, ptr: new([3]int), out: [3]int{1, 2, 3}}, {in: `[1, 2, 3]`, ptr: new([1]int), out: [1]int{1}}, {in: `[1, 2, 3]`, ptr: new([5]int), out: [5]int{1, 2, 3, 0, 0}}, + {in: `[1, 2, 3]`, ptr: new(MustNotUnmarshalJSON), err: errors.New("MustNotUnmarshalJSON was used")}, // empty array to interface test {in: `[]`, ptr: new([]interface{}), out: []interface{}{}}, @@ -826,6 +828,7 @@ var unmarshalTests = []unmarshalTest{ {in: `{"B": "False"}`, ptr: new(B), err: errors.New(`json: invalid use of ,string struct tag, trying to unmarshal "False" into bool`)}, {in: `{"B": "null"}`, ptr: new(B), out: B{false}}, {in: `{"B": "nul"}`, ptr: new(B), err: errors.New(`json: invalid use of ,string struct tag, trying to unmarshal "nul" into bool`)}, + {in: `{"B": [2, 3]}`, ptr: new(B), err: errors.New(`json: invalid use of ,string struct tag, trying to unmarshal unquoted value into bool`)}, // additional tests for disallowUnknownFields { @@ -894,6 +897,18 @@ var unmarshalTests = []unmarshalTest{ ptr: new(mapStringToStringData), err: &UnmarshalTypeError{Value: "number", Type: reflect.TypeOf(""), Offset: 21, Struct: "mapStringToStringData", Field: "data"}, }, + + // trying to decode JSON arrays or objects via TextUnmarshaler + { + in: `[1, 2, 3]`, + ptr: new(MustNotUnmarshalText), + err: &UnmarshalTypeError{Value: "array", Type: reflect.TypeOf(&MustNotUnmarshalText{}), Offset: 1}, + }, + { + in: `{"foo": "bar"}`, + ptr: new(MustNotUnmarshalText), + err: &UnmarshalTypeError{Value: "object", Type: reflect.TypeOf(&MustNotUnmarshalText{}), Offset: 1}, + }, } func TestMarshal(t *testing.T) { @@ -1955,10 +1970,12 @@ type unexportedFields struct { Name string m map[string]interface{} `json:"-"` m2 map[string]interface{} `json:"abcd"` + + s []int `json:"-"` } func TestUnmarshalUnexported(t *testing.T) { - input := `{"Name": "Bob", "m": {"x": 123}, "m2": {"y": 456}, "abcd": {"z": 789}}` + input := `{"Name": "Bob", "m": {"x": 123}, "m2": {"y": 456}, "abcd": {"z": 789}, "s": [2, 3]}` want := &unexportedFields{Name: "Bob"} out := &unexportedFields{} diff --git a/src/flag/flag.go b/src/flag/flag.go index 2cd7829c1a..ae84e1f775 100644 --- a/src/flag/flag.go +++ b/src/flag/flag.go @@ -472,7 +472,7 @@ func (f *FlagSet) PrintDefaults() { // for both 4- and 8-space tab stops. s += "\n \t" } - s += strings.Replace(usage, "\n", "\n \t", -1) + s += strings.ReplaceAll(usage, "\n", "\n \t") if !isZeroValue(flag, flag.DefValue) { if _, ok := flag.Value.(*stringValue); ok { diff --git a/src/fmt/example_test.go b/src/fmt/example_test.go index 1479b761b6..ecf3391ce7 100644 --- a/src/fmt/example_test.go +++ b/src/fmt/example_test.go @@ -7,8 +7,10 @@ package fmt_test import ( "fmt" "io" + "math" "os" "strings" + "time" ) // The Errorf function lets us use formatting features @@ -17,6 +19,7 @@ func ExampleErrorf() { const name, id = "bueller", 17 err := fmt.Errorf("user %q (id %d) not found", name, id) fmt.Println(err.Error()) + // Output: user "bueller" (id 17) not found } @@ -29,7 +32,7 @@ func ExampleFscanf() { r := strings.NewReader("5 true gophers") n, err := fmt.Fscanf(r, "%d %t %s", &i, &b, &s) if err != nil { - panic(err) + fmt.Fprintf(os.Stderr, "Fscanf: %v\n", err) } fmt.Println(i, b, s) fmt.Println(n) @@ -38,47 +41,6 @@ func ExampleFscanf() { // 3 } -func ExampleSprintf() { - i := 30 - s := "Aug" - sf := fmt.Sprintf("Today is %d %s", i, s) - fmt.Println(sf) - fmt.Println(len(sf)) - // Output: - // Today is 30 Aug - // 15 -} - -func ExamplePrintln() { - n, err := fmt.Println("there", "are", 99, "gophers") - if err != nil { - panic(err) - } - fmt.Print(n) - // Output: - // there are 99 gophers - // 21 -} - -func ExampleSprintln() { - s := "Aug" - sl := fmt.Sprintln("Today is 30", s) - fmt.Printf("%q", sl) - // Output: - // "Today is 30 Aug\n" -} - -func ExampleFprintln() { - n, err := fmt.Fprintln(os.Stdout, "there", "are", 99, "gophers") - if err != nil { - panic(err) - } - fmt.Print(n) - // Output: - // there are 99 gophers - // 21 -} - func ExampleFscanln() { s := `dmr 1771 1.61803398875 ken 271828 3.14159` @@ -100,3 +62,292 @@ func ExampleFscanln() { // 3: dmr, 1771, 1.618034 // 3: ken, 271828, 3.141590 } + +func ExamplePrint() { + const name, age = "Kim", 22 + fmt.Print(name, " is ", age, " years old.\n") + + // It is conventional not to worry about any + // error returned by Print. + + // Output: + // Kim is 22 years old. +} + +func ExamplePrintln() { + const name, age = "Kim", 22 + fmt.Println(name, "is", age, "years old.") + + // It is conventional not to worry about any + // error returned by Println. + + // Output: + // Kim is 22 years old. +} + +func ExamplePrintf() { + const name, age = "Kim", 22 + fmt.Printf("%s is %d years old.\n", name, age) + + // It is conventional not to worry about any + // error returned by Printf. + + // Output: + // Kim is 22 years old. +} + +func ExampleSprint() { + const name, age = "Kim", 22 + s := fmt.Sprint(name, " is ", age, " years old.\n") + + io.WriteString(os.Stdout, s) // Ignoring error for simplicity. + + // Output: + // Kim is 22 years old. +} + +func ExampleSprintln() { + const name, age = "Kim", 22 + s := fmt.Sprintln(name, "is", age, "years old.") + + io.WriteString(os.Stdout, s) // Ignoring error for simplicity. + + // Output: + // Kim is 22 years old. +} + +func ExampleSprintf() { + const name, age = "Kim", 22 + s := fmt.Sprintf("%s is %d years old.\n", name, age) + + io.WriteString(os.Stdout, s) // Ignoring error for simplicity. + + // Output: + // Kim is 22 years old. +} + +func ExampleFprint() { + const name, age = "Kim", 22 + n, err := fmt.Fprint(os.Stdout, name, " is ", age, " years old.\n") + + // The n and err return values from Fprint are + // those returned by the underlying io.Writer. + if err != nil { + fmt.Fprintf(os.Stderr, "Fprint: %v\n", err) + } + fmt.Print(n, " bytes written.\n") + + // Output: + // Kim is 22 years old. + // 21 bytes written. +} + +func ExampleFprintln() { + const name, age = "Kim", 22 + n, err := fmt.Fprintln(os.Stdout, name, "is", age, "years old.") + + // The n and err return values from Fprintln are + // those returned by the underlying io.Writer. + if err != nil { + fmt.Fprintf(os.Stderr, "Fprintln: %v\n", err) + } + fmt.Println(n, "bytes written.") + + // Output: + // Kim is 22 years old. + // 21 bytes written. +} + +func ExampleFprintf() { + const name, age = "Kim", 22 + n, err := fmt.Fprintf(os.Stdout, "%s is %d years old.\n", name, age) + + // The n and err return values from Fprintf are + // those returned by the underlying io.Writer. + if err != nil { + fmt.Fprintf(os.Stderr, "Fprintf: %v\n", err) + } + fmt.Printf("%d bytes written.\n", n) + + // Output: + // Kim is 22 years old. + // 21 bytes written. +} + +// Print, Println, and Printf lay out their arguments differently. In this example +// we can compare their behaviors. Println always adds blanks between the items it +// prints, while Print adds blanks only between non-string arguments and Printf +// does exactly what it is told. +// Sprint, Sprintln, Sprintf, Fprint, Fprintln, and Fprintf behave the same as +// their corresponding Print, Println, and Printf functions shown here. +func Example_printers() { + a, b := 3.0, 4.0 + h := math.Hypot(a, b) + + // Print inserts blanks between arguments when neither is a string. + // It does not add a newline to the output, so we add one explicitly. + fmt.Print("The vector (", a, b, ") has length ", h, ".\n") + + // Println always inserts spaces between its arguments, + // so it cannot be used to produce the same output as Print in this case; + // its output has extra spaces. + // Also, Println always adds a newline to the output. + fmt.Println("The vector (", a, b, ") has length", h, ".") + + // Printf provides complete control but is more complex to use. + // It does not add a newline to the output, so we add one explicitly + // at the end of the format specifier string. + fmt.Printf("The vector (%g %g) has length %g.\n", a, b, h) + + // Output: + // The vector (3 4) has length 5. + // The vector ( 3 4 ) has length 5 . + // The vector (3 4) has length 5. +} + +// These examples demonstrate the basics of printing using a format string. Printf, +// Sprintf, and Fprintf all take a format string that specifies how to format the +// subsequent arguments. For example, %d (we call that a 'verb') says to print the +// corresponding argument, which must be an integer (or something containing an +// integer, such as a slice of ints) in decimal. The verb %v ('v' for 'value') +// always formats the argument in its default form, just how Print or Println would +// show it. The special verb %T ('T' for 'Type') prints the type of the argument +// rather than its value. The examples are not exhaustive; see the package comment +// for all the details. +func Example_formats() { + // A basic set of examples showing that %v is the default format, in this + // case decimal for integers, which can be explicitly requested with %d; + // the output is just what Println generates. + integer := 23 + // Each of these prints "23" (without the quotes). + fmt.Println(integer) + fmt.Printf("%v\n", integer) + fmt.Printf("%d\n", integer) + + // The special verb %T shows the type of an item rather than its value. + fmt.Printf("%T %T\n", integer, &integer) + // Result: int *int + + // Println(x) is the same as Printf("%v\n", x) so we will use only Printf + // in the following examples. Each one demonstrates how to format values of + // a particular type, such as integers or strings. We start each format + // string with %v to show the default output and follow that with one or + // more custom formats. + + // Booleans print as "true" or "false" with %v or %t. + truth := true + fmt.Printf("%v %t\n", truth, truth) + // Result: true true + + // Integers print as decimals with %v and %d, + // or in hex with %x, octal with %o, or binary with %b. + answer := 42 + fmt.Printf("%v %d %x %o %b\n", answer, answer, answer, answer, answer) + // Result: 42 42 2a 52 101010 + + // Floats have multiple formats: %v and %g print a compact representation, + // while %f prints a decimal point and %e uses exponential notation. The + // format %6.2f used here shows how to set the width and precision to + // control the appearance of a floating-point value. In this instance, 6 is + // the total width of the printed text for the value (note the extra spaces + // in the output) and 2 is the number of decimal places to show. + pi := math.Pi + fmt.Printf("%v %g %.2f (%6.2f) %e\n", pi, pi, pi, pi, pi) + // Result: 3.141592653589793 3.141592653589793 3.14 ( 3.14) 3.141593e+00 + + // Complex numbers format as parenthesized pairs of floats, with an 'i' + // after the imaginary part. + point := 110.7 + 22.5i + fmt.Printf("%v %g %.2f %.2e\n", point, point, point, point) + // Result: (110.7+22.5i) (110.7+22.5i) (110.70+22.50i) (1.11e+02+2.25e+01i) + + // Runes are integers but when printed with %c show the character with that + // Unicode value. The %q verb shows them as quoted characters, %U as a + // hex Unicode code point, and %#U as both a code point and a quoted + // printable form if the rune is printable. + smile := '😀' + fmt.Printf("%v %d %c %q %U %#U\n", smile, smile, smile, smile, smile, smile) + // Result: 128512 128512 😀 '😀' U+1F600 U+1F600 '😀' + + // Strings are formatted with %v and %s as-is, with %q as quoted strings, + // and %#q as backquoted strings. + placeholders := `foo "bar"` + fmt.Printf("%v %s %q %#q\n", placeholders, placeholders, placeholders, placeholders) + // Result: foo "bar" foo "bar" "foo \"bar\"" `foo "bar"` + + // Maps formatted with %v show keys and values in their default formats. + // The %#v form (the # is called a "flag" in this context) shows the map in + // the Go source format. + isLegume := map[string]bool{ + "peanut": true, + // TODO: Include this line when maps are printed in deterministic order. + // See Issue #21095 + // "dachshund": false, + } + fmt.Printf("%v %#v\n", isLegume, isLegume) + // Result: map[peanut:true] map[string]bool{"peanut":true} + + // Structs formatted with %v show field values in their default formats. + // The %+v form shows the fields by name, while %#v formats the struct in + // Go source format. + person := struct { + Name string + Age int + }{"Kim", 22} + fmt.Printf("%v %+v %#v\n", person, person, person) + // Result: {Kim 22} {Name:Kim Age:22} struct { Name string; Age int }{Name:"Kim", Age:22} + + // The default format for a pointer shows the underlying value preceded by + // an ampersand. The %p verb prints the pointer value in hex. We use a + // typed nil for the argument to %p here because the value of any non-nil + // pointer would change from run to run; run the commented-out Printf + // call yourself to see. + pointer := &person + fmt.Printf("%v %p\n", pointer, (*int)(nil)) + // Result: &{Kim 22} 0x0 + // fmt.Printf("%v %p\n", pointer, pointer) + // Result: &{Kim 22} 0x010203 // See comment above. + + // Arrays and slices are formatted by applying the format to each element. + greats := [5]string{"Katano", "Kobayashi", "Kurosawa", "Miyazaki", "Ozu"} + fmt.Printf("%v %q\n", greats, greats) + // Result: [Katano Kobayashi Kurosawa Miyazaki Ozu] ["Katano" "Kobayashi" "Kurosawa" "Miyazaki" "Ozu"] + + kGreats := greats[:3] + fmt.Printf("%v %q %#v\n", kGreats, kGreats, kGreats) + // Result: [Katano Kobayashi Kurosawa] ["Katano" "Kobayashi" "Kurosawa"] []string{"Katano", "Kobayashi", "Kurosawa"} + + // Byte slices are special. Integer verbs like %d print the elements in + // that format. The %s and %q forms treat the slice like a string. The %x + // verb has a special form with the space flag that puts a space between + // the bytes. + cmd := []byte("a⌘") + fmt.Printf("%v %d %s %q %x % x\n", cmd, cmd, cmd, cmd, cmd, cmd) + // Result: [97 226 140 152] [97 226 140 152] a⌘ "a⌘" 61e28c98 61 e2 8c 98 + + // Types that implement Stringer are printed the same as strings. Because + // Stringers return a string, we can print them using a string-specific + // verb such as %q. + now := time.Unix(123456789, 0).UTC() // time.Time implements fmt.Stringer. + fmt.Printf("%v %q\n", now, now) + // Result: 1973-11-29 21:33:09 +0000 UTC "1973-11-29 21:33:09 +0000 UTC" + + // Output: + // 23 + // 23 + // 23 + // int *int + // true true + // 42 42 2a 52 101010 + // 3.141592653589793 3.141592653589793 3.14 ( 3.14) 3.141593e+00 + // (110.7+22.5i) (110.7+22.5i) (110.70+22.50i) (1.11e+02+2.25e+01i) + // 128512 128512 😀 '😀' U+1F600 U+1F600 '😀' + // foo "bar" foo "bar" "foo \"bar\"" `foo "bar"` + // map[peanut:true] map[string]bool{"peanut":true} + // {Kim 22} {Name:Kim Age:22} struct { Name string; Age int }{Name:"Kim", Age:22} + // &{Kim 22} 0x0 + // [Katano Kobayashi Kurosawa Miyazaki Ozu] ["Katano" "Kobayashi" "Kurosawa" "Miyazaki" "Ozu"] + // [Katano Kobayashi Kurosawa] ["Katano" "Kobayashi" "Kurosawa"] []string{"Katano", "Kobayashi", "Kurosawa"} + // [97 226 140 152] [97 226 140 152] a⌘ "a⌘" 61e28c98 61 e2 8c 98 + // 1973-11-29 21:33:09 +0000 UTC "1973-11-29 21:33:09 +0000 UTC" +} diff --git a/src/fmt/fmt_test.go b/src/fmt/fmt_test.go index 9581becd32..d63271a805 100644 --- a/src/fmt/fmt_test.go +++ b/src/fmt/fmt_test.go @@ -131,15 +131,10 @@ func (byteFormatter) Format(f State, _ rune) { var byteFormatterSlice = []byteFormatter{'h', 'e', 'l', 'l', 'o'} -// Copy of io.stringWriter interface used by writeStringFormatter for type assertion. -type stringWriter interface { - WriteString(s string) (n int, err error) -} - type writeStringFormatter string func (sf writeStringFormatter) Format(f State, c rune) { - if sw, ok := f.(stringWriter); ok { + if sw, ok := f.(io.StringWriter); ok { sw.WriteString("***" + string(sf) + "***") } } diff --git a/src/fmt/print.go b/src/fmt/print.go index c9d694b07d..32743d0712 100644 --- a/src/fmt/print.go +++ b/src/fmt/print.go @@ -139,6 +139,16 @@ func newPrinter() *pp { // free saves used pp structs in ppFree; avoids an allocation per invocation. func (p *pp) free() { + // Proper usage of a sync.Pool requires each entry to have approximately + // the same memory cost. To obtain this property when the stored type + // contains a variably-sized buffer, we add a hard limit on the maximum buffer + // to place back in the pool. + // + // See https://golang.org/issue/23199 + if cap(p.buf) > 64<<10 { + return + } + p.buf = p.buf[:0] p.arg = nil p.value = reflect.Value{} diff --git a/src/go/build/build.go b/src/go/build/build.go index b68a712a7d..fc8d37789f 100644 --- a/src/go/build/build.go +++ b/src/go/build/build.go @@ -12,6 +12,7 @@ import ( "go/doc" "go/parser" "go/token" + "internal/goroot" "io" "io/ioutil" "log" @@ -543,7 +544,7 @@ func (ctxt *Context) Import(path string, srcDir string, mode ImportMode) (*Packa inTestdata := func(sub string) bool { return strings.Contains(sub, "/testdata/") || strings.HasSuffix(sub, "/testdata") || strings.HasPrefix(sub, "testdata/") || sub == "testdata" } - if ctxt.GOROOT != "" && ctxt.Compiler != "gccgo" { + if ctxt.GOROOT != "" { root := ctxt.joinPath(ctxt.GOROOT, "src") if sub, ok := ctxt.hasSubdir(root, p.Dir); ok && !inTestdata(sub) { p.Goroot = true @@ -656,7 +657,7 @@ func (ctxt *Context) Import(path string, srcDir string, mode ImportMode) (*Packa } tried.goroot = dir } - if ctxt.Compiler == "gccgo" && isStandardPackage(path) { + if ctxt.Compiler == "gccgo" && goroot.IsStandardPackage(ctxt.GOROOT, ctxt.Compiler, path) { p.Dir = ctxt.joinPath(ctxt.GOROOT, "src", path) p.Goroot = true p.Root = ctxt.GOROOT @@ -714,6 +715,11 @@ Found: // non-nil *Package returned when an error occurs. // We need to do this before we return early on FindOnly flag. if IsLocalImport(path) && !ctxt.isDir(p.Dir) { + if ctxt.Compiler == "gccgo" && p.Goroot { + // gccgo has no sources for GOROOT packages. + return p, nil + } + // package was not found return p, fmt.Errorf("cannot find package %q in:\n\t%s", path, p.Dir) } diff --git a/src/go/build/deps_test.go b/src/go/build/deps_test.go index f0e584585b..c15706fb6b 100644 --- a/src/go/build/deps_test.go +++ b/src/go/build/deps_test.go @@ -265,7 +265,7 @@ var pkgDeps = map[string][]string{ "encoding/pem": {"L4"}, "encoding/xml": {"L4", "encoding"}, "flag": {"L4", "OS"}, - "go/build": {"L4", "OS", "GOPARSER"}, + "go/build": {"L4", "OS", "GOPARSER", "internal/goroot"}, "html": {"L4"}, "image/draw": {"L4", "image/internal/imageutil"}, "image/gif": {"L4", "compress/lzw", "image/color/palette", "image/draw"}, @@ -273,6 +273,7 @@ var pkgDeps = map[string][]string{ "image/jpeg": {"L4", "image/internal/imageutil"}, "image/png": {"L4", "compress/zlib"}, "index/suffixarray": {"L4", "regexp"}, + "internal/goroot": {"L4", "OS"}, "internal/singleflight": {"sync"}, "internal/trace": {"L4", "OS"}, "math/big": {"L4"}, diff --git a/src/go/build/doc.go b/src/go/build/doc.go index 69613e359c..d803b8967b 100644 --- a/src/go/build/doc.go +++ b/src/go/build/doc.go @@ -110,6 +110,9 @@ // - "go1.11", from Go version 1.11 onward // - any additional words listed in ctxt.BuildTags // +// There are no build tags for beta or minor releases. Programs that need the +// minor release number can call runtime.Version. +// // If a file's name, after stripping the extension and a possible _test suffix, // matches any of the following patterns: // *_GOOS diff --git a/src/go/build/gc.go b/src/go/build/gc.go index e2be2cbb1d..3025cd5681 100644 --- a/src/go/build/gc.go +++ b/src/go/build/gc.go @@ -7,131 +7,11 @@ package build import ( - "os" - "os/exec" "path/filepath" "runtime" - "strings" - "sync" ) // getToolDir returns the default value of ToolDir. func getToolDir() string { return filepath.Join(runtime.GOROOT(), "pkg/tool/"+runtime.GOOS+"_"+runtime.GOARCH) } - -// isStandardPackage is not used for the gc toolchain. -// However, this function may be called when using `go build -compiler=gccgo`. -func isStandardPackage(path string) bool { - return gccgoSearch.isStandard(path) -} - -// gccgoSearch holds the gccgo search directories. -type gccgoDirs struct { - once sync.Once - dirs []string -} - -// gccgoSearch is used to check whether a gccgo package exists in the -// standard library. -var gccgoSearch gccgoDirs - -// init finds the gccgo search directories. If this fails it leaves dirs == nil. -func (gd *gccgoDirs) init() { - gccgo := os.Getenv("GCCGO") - if gccgo == "" { - gccgo = "gccgo" - } - bin, err := exec.LookPath(gccgo) - if err != nil { - return - } - - allDirs, err := exec.Command(bin, "-print-search-dirs").Output() - if err != nil { - return - } - versionB, err := exec.Command(bin, "-dumpversion").Output() - if err != nil { - return - } - version := strings.TrimSpace(string(versionB)) - machineB, err := exec.Command(bin, "-dumpmachine").Output() - if err != nil { - return - } - machine := strings.TrimSpace(string(machineB)) - - dirsEntries := strings.Split(string(allDirs), "\n") - const prefix = "libraries: =" - var dirs []string - for _, dirEntry := range dirsEntries { - if strings.HasPrefix(dirEntry, prefix) { - dirs = filepath.SplitList(strings.TrimPrefix(dirEntry, prefix)) - break - } - } - if len(dirs) == 0 { - return - } - - var lastDirs []string - for _, dir := range dirs { - goDir := filepath.Join(dir, "go", version) - if fi, err := os.Stat(goDir); err == nil && fi.IsDir() { - gd.dirs = append(gd.dirs, goDir) - goDir = filepath.Join(goDir, machine) - if fi, err = os.Stat(goDir); err == nil && fi.IsDir() { - gd.dirs = append(gd.dirs, goDir) - } - } - if fi, err := os.Stat(dir); err == nil && fi.IsDir() { - lastDirs = append(lastDirs, dir) - } - } - gd.dirs = append(gd.dirs, lastDirs...) -} - -// isStandard returns whether path is a standard library for gccgo. -func (gd *gccgoDirs) isStandard(path string) bool { - // Quick check: if the first path component has a '.', it's not - // in the standard library. This skips most GOPATH directories. - i := strings.Index(path, "/") - if i < 0 { - i = len(path) - } - if strings.Contains(path[:i], ".") { - return false - } - - if path == "unsafe" { - // Special case. - return true - } - - gd.once.Do(gd.init) - if gd.dirs == nil { - // We couldn't find the gccgo search directories. - // Best guess, since the first component did not contain - // '.', is that this is a standard library package. - return true - } - - for _, dir := range gd.dirs { - full := filepath.Join(dir, path) - pkgdir, pkg := filepath.Split(full) - for _, p := range [...]string{ - full, - full + ".gox", - pkgdir + "lib" + pkg + ".so", - pkgdir + "lib" + pkg + ".a", - full + ".o", - } { - if fi, err := os.Stat(p); err == nil && !fi.IsDir() { - return true - } - } - } - - return false -} diff --git a/src/go/build/gccgo.go b/src/go/build/gccgo.go index 59e089d69d..c6aac9aa1b 100644 --- a/src/go/build/gccgo.go +++ b/src/go/build/gccgo.go @@ -12,9 +12,3 @@ import "runtime" func getToolDir() string { return envOr("GCCGOTOOLDIR", runtime.GCCGOTOOLDIR) } - -// isStandardPackage returns whether path names a standard library package. -// This uses a list generated at build time. -func isStandardPackage(path string) bool { - return stdpkg[path] -} diff --git a/src/go/build/syslist.go b/src/go/build/syslist.go index d7938fad54..597212b6d0 100644 --- a/src/go/build/syslist.go +++ b/src/go/build/syslist.go @@ -4,5 +4,5 @@ package build -const goosList = "android darwin dragonfly freebsd js linux nacl netbsd openbsd plan9 solaris windows zos " +const goosList = "aix android darwin dragonfly freebsd js linux nacl netbsd openbsd plan9 solaris windows zos " const goarchList = "386 amd64 amd64p32 arm armbe arm64 arm64be ppc64 ppc64le mips mipsle mips64 mips64le mips64p32 mips64p32le ppc riscv riscv64 s390 s390x sparc sparc64 wasm " diff --git a/src/go/constant/value_test.go b/src/go/constant/value_test.go index e6fca76e18..68b87eaa55 100644 --- a/src/go/constant/value_test.go +++ b/src/go/constant/value_test.go @@ -296,7 +296,7 @@ func val(lit string) Value { switch first, last := lit[0], lit[len(lit)-1]; { case first == '"' || first == '`': tok = token.STRING - lit = strings.Replace(lit, "_", " ", -1) + lit = strings.ReplaceAll(lit, "_", " ") case first == '\'': tok = token.CHAR case last == 'i': diff --git a/src/go/doc/doc_test.go b/src/go/doc/doc_test.go index 902a79f63f..0b2d2b63cc 100644 --- a/src/go/doc/doc_test.go +++ b/src/go/doc/doc_test.go @@ -40,7 +40,7 @@ func readTemplate(filename string) *template.Template { func nodeFmt(node interface{}, fset *token.FileSet) string { var buf bytes.Buffer printer.Fprint(&buf, fset, node) - return strings.Replace(strings.TrimSpace(buf.String()), "\n", "\n\t", -1) + return strings.ReplaceAll(strings.TrimSpace(buf.String()), "\n", "\n\t") } func synopsisFmt(s string) string { @@ -53,7 +53,7 @@ func synopsisFmt(s string) string { } s = strings.TrimSpace(s) + " ..." } - return "// " + strings.Replace(s, "\n", " ", -1) + return "// " + strings.ReplaceAll(s, "\n", " ") } func indentFmt(indent, s string) string { @@ -62,7 +62,7 @@ func indentFmt(indent, s string) string { end = "\n" s = s[:len(s)-1] } - return indent + strings.Replace(s, "\n", "\n"+indent, -1) + end + return indent + strings.ReplaceAll(s, "\n", "\n"+indent) + end } func isGoFile(fi os.FileInfo) bool { diff --git a/src/go/internal/gccgoimporter/importer_test.go b/src/go/internal/gccgoimporter/importer_test.go index 5a699687bd..15494fd6b3 100644 --- a/src/go/internal/gccgoimporter/importer_test.go +++ b/src/go/internal/gccgoimporter/importer_test.go @@ -102,8 +102,10 @@ var importerTests = [...]importerTest{ {pkgpath: "unicode", name: "MaxRune", want: "const MaxRune untyped rune", wantval: "1114111"}, {pkgpath: "imports", wantinits: []string{"imports..import", "fmt..import", "math..import"}}, {pkgpath: "importsar", name: "Hello", want: "var Hello string"}, - {pkgpath: "alias", name: "IntAlias2", want: "type IntAlias2 = Int"}, + {pkgpath: "aliases", name: "A14", want: "type A14 = func(int, T0) chan T2"}, + {pkgpath: "aliases", name: "C0", want: "type C0 struct{f1 C1; f2 C1}"}, {pkgpath: "escapeinfo", name: "NewT", want: "func NewT(data []byte) *T"}, + {pkgpath: "issue27856", name: "M", want: "type M struct{E F}"}, } func TestGoxImporter(t *testing.T) { diff --git a/src/go/internal/gccgoimporter/parser.go b/src/go/internal/gccgoimporter/parser.go index 9f8c19b638..9a94c3369e 100644 --- a/src/go/internal/gccgoimporter/parser.go +++ b/src/go/internal/gccgoimporter/parser.go @@ -26,7 +26,7 @@ type parser struct { pkgname string // name of imported package pkg *types.Package // reference to imported package imports map[string]*types.Package // package path -> package object - typeMap map[int]types.Type // type number -> type + typeList []types.Type // type number -> type initdata InitData // package init priority data } @@ -38,7 +38,7 @@ func (p *parser) init(filename string, src io.Reader, imports map[string]*types. p.scanner.Filename = filename // for good error messages p.next() p.imports = imports - p.typeMap = make(map[int]types.Type) + p.typeList = make([]types.Type, 1 /* type numbers start at 1 */, 16) } type importError struct { @@ -378,52 +378,80 @@ func (p *parser) parseConst(pkg *types.Package) *types.Const { return types.NewConst(token.NoPos, pkg, name, typ, val) } +// reserved is a singleton type used to fill type map slots that have +// been reserved (i.e., for which a type number has been parsed) but +// which don't have their actual type yet. When the type map is updated, +// the actual type must replace a reserved entry (or we have an internal +// error). Used for self-verification only - not required for correctness. +var reserved = new(struct{ types.Type }) + +// reserve reserves the type map entry n for future use. +func (p *parser) reserve(n int) { + if n != len(p.typeList) { + p.errorf("invalid type number %d (out of sync)", n) + } + p.typeList = append(p.typeList, reserved) +} + +// update sets the type map entries for the given type numbers nlist to t. +func (p *parser) update(t types.Type, nlist []int) { + for _, n := range nlist { + if p.typeList[n] != reserved { + p.errorf("typeMap[%d] not reserved", n) + } + p.typeList[n] = t + } +} + // NamedType = TypeName [ "=" ] Type { Method } . // TypeName = ExportedName . // Method = "func" "(" Param ")" Name ParamList ResultList ";" . -func (p *parser) parseNamedType(n int) types.Type { +func (p *parser) parseNamedType(nlist []int) types.Type { pkg, name := p.parseExportedName() scope := pkg.Scope() + obj := scope.Lookup(name) + if obj != nil && obj.Type() == nil { + p.errorf("%v has nil type", obj) + } + // type alias if p.tok == '=' { - // type alias p.next() - typ := p.parseType(pkg) - if obj := scope.Lookup(name); obj != nil { - typ = obj.Type() // use previously imported type - if typ == nil { - p.errorf("%v (type alias) used in cycle", obj) - } - } else { - obj = types.NewTypeName(token.NoPos, pkg, name, typ) - scope.Insert(obj) + if obj != nil { + // use the previously imported (canonical) type + t := obj.Type() + p.update(t, nlist) + p.parseType(pkg) // discard + return t } - p.typeMap[n] = typ - return typ + t := p.parseType(pkg, nlist...) + obj = types.NewTypeName(token.NoPos, pkg, name, t) + scope.Insert(obj) + return t } - // named type - obj := scope.Lookup(name) + // defined type if obj == nil { - // a named type may be referred to before the underlying type - // is known - set it up + // A named type may be referred to before the underlying type + // is known - set it up. tname := types.NewTypeName(token.NoPos, pkg, name, nil) types.NewNamed(tname, nil, nil) scope.Insert(tname) obj = tname } - typ := obj.Type() - p.typeMap[n] = typ + // use the previously imported (canonical), or newly created type + t := obj.Type() + p.update(t, nlist) - nt, ok := typ.(*types.Named) + nt, ok := t.(*types.Named) if !ok { // This can happen for unsafe.Pointer, which is a TypeName holding a Basic type. pt := p.parseType(pkg) - if pt != typ { + if pt != t { p.error("unexpected underlying type for non-named TypeName") } - return typ + return t } underlying := p.parseType(pkg) @@ -449,41 +477,70 @@ func (p *parser) parseNamedType(n int) types.Type { return nt } -func (p *parser) parseInt() int64 { +func (p *parser) parseInt64() int64 { lit := p.expect(scanner.Int) - n, err := strconv.ParseInt(lit, 10, 0) + n, err := strconv.ParseInt(lit, 10, 64) if err != nil { p.error(err) } return n } +func (p *parser) parseInt() int { + lit := p.expect(scanner.Int) + n, err := strconv.ParseInt(lit, 10, 0 /* int */) + if err != nil { + p.error(err) + } + return int(n) +} + // ArrayOrSliceType = "[" [ int ] "]" Type . -func (p *parser) parseArrayOrSliceType(pkg *types.Package) types.Type { +func (p *parser) parseArrayOrSliceType(pkg *types.Package, nlist []int) types.Type { p.expect('[') if p.tok == ']' { p.next() - return types.NewSlice(p.parseType(pkg)) + + t := new(types.Slice) + p.update(t, nlist) + + *t = *types.NewSlice(p.parseType(pkg)) + return t } - n := p.parseInt() + t := new(types.Array) + p.update(t, nlist) + + len := p.parseInt64() p.expect(']') - return types.NewArray(p.parseType(pkg), n) + + *t = *types.NewArray(p.parseType(pkg), len) + return t } // MapType = "map" "[" Type "]" Type . -func (p *parser) parseMapType(pkg *types.Package) types.Type { +func (p *parser) parseMapType(pkg *types.Package, nlist []int) types.Type { p.expectKeyword("map") + + t := new(types.Map) + p.update(t, nlist) + p.expect('[') key := p.parseType(pkg) p.expect(']') elem := p.parseType(pkg) - return types.NewMap(key, elem) + + *t = *types.NewMap(key, elem) + return t } // ChanType = "chan" ["<-" | "-<"] Type . -func (p *parser) parseChanType(pkg *types.Package) types.Type { +func (p *parser) parseChanType(pkg *types.Package, nlist []int) types.Type { p.expectKeyword("chan") + + t := new(types.Chan) + p.update(t, nlist) + dir := types.SendRecv switch p.tok { case '-': @@ -500,13 +557,17 @@ func (p *parser) parseChanType(pkg *types.Package) types.Type { } } - return types.NewChan(dir, p.parseType(pkg)) + *t = *types.NewChan(dir, p.parseType(pkg)) + return t } // StructType = "struct" "{" { Field } "}" . -func (p *parser) parseStructType(pkg *types.Package) types.Type { +func (p *parser) parseStructType(pkg *types.Package, nlist []int) types.Type { p.expectKeyword("struct") + t := new(types.Struct) + p.update(t, nlist) + var fields []*types.Var var tags []string @@ -519,7 +580,8 @@ func (p *parser) parseStructType(pkg *types.Package) types.Type { } p.expect('}') - return types.NewStruct(fields, tags) + *t = *types.NewStruct(fields, tags) + return t } // ParamList = "(" [ { Parameter "," } Parameter ] ")" . @@ -562,10 +624,15 @@ func (p *parser) parseResultList(pkg *types.Package) *types.Tuple { } // FunctionType = ParamList ResultList . -func (p *parser) parseFunctionType(pkg *types.Package) *types.Signature { +func (p *parser) parseFunctionType(pkg *types.Package, nlist []int) *types.Signature { + t := new(types.Signature) + p.update(t, nlist) + params, isVariadic := p.parseParamList(pkg) results := p.parseResultList(pkg) - return types.NewSignature(nil, params, results, isVariadic) + + *t = *types.NewSignature(nil, params, results, isVariadic) + return t } // Func = Name FunctionType . @@ -577,13 +644,16 @@ func (p *parser) parseFunc(pkg *types.Package) *types.Func { p.discardDirectiveWhileParsingTypes(pkg) return nil } - return types.NewFunc(token.NoPos, pkg, name, p.parseFunctionType(pkg)) + return types.NewFunc(token.NoPos, pkg, name, p.parseFunctionType(pkg, nil)) } // InterfaceType = "interface" "{" { ("?" Type | Func) ";" } "}" . -func (p *parser) parseInterfaceType(pkg *types.Package) types.Type { +func (p *parser) parseInterfaceType(pkg *types.Package, nlist []int) types.Type { p.expectKeyword("interface") + t := new(types.Interface) + p.update(t, nlist) + var methods []*types.Func var embeddeds []types.Type @@ -600,53 +670,61 @@ func (p *parser) parseInterfaceType(pkg *types.Package) types.Type { } p.expect('}') - return types.NewInterfaceType(methods, embeddeds) + *t = *types.NewInterfaceType(methods, embeddeds) + return t } // PointerType = "*" ("any" | Type) . -func (p *parser) parsePointerType(pkg *types.Package) types.Type { +func (p *parser) parsePointerType(pkg *types.Package, nlist []int) types.Type { p.expect('*') if p.tok == scanner.Ident { p.expectKeyword("any") - return types.Typ[types.UnsafePointer] + t := types.Typ[types.UnsafePointer] + p.update(t, nlist) + return t } - return types.NewPointer(p.parseType(pkg)) + + t := new(types.Pointer) + p.update(t, nlist) + + *t = *types.NewPointer(p.parseType(pkg)) + + return t } -// TypeDefinition = NamedType | MapType | ChanType | StructType | InterfaceType | PointerType | ArrayOrSliceType | FunctionType . -func (p *parser) parseTypeDefinition(pkg *types.Package, n int) types.Type { - var t types.Type +// TypeSpec = NamedType | MapType | ChanType | StructType | InterfaceType | PointerType | ArrayOrSliceType | FunctionType . +func (p *parser) parseTypeSpec(pkg *types.Package, nlist []int) types.Type { switch p.tok { case scanner.String: - t = p.parseNamedType(n) + return p.parseNamedType(nlist) case scanner.Ident: switch p.lit { case "map": - t = p.parseMapType(pkg) + return p.parseMapType(pkg, nlist) case "chan": - t = p.parseChanType(pkg) + return p.parseChanType(pkg, nlist) case "struct": - t = p.parseStructType(pkg) + return p.parseStructType(pkg, nlist) case "interface": - t = p.parseInterfaceType(pkg) + return p.parseInterfaceType(pkg, nlist) } case '*': - t = p.parsePointerType(pkg) + return p.parsePointerType(pkg, nlist) case '[': - t = p.parseArrayOrSliceType(pkg) + return p.parseArrayOrSliceType(pkg, nlist) case '(': - t = p.parseFunctionType(pkg) + return p.parseFunctionType(pkg, nlist) } - p.typeMap[n] = t - return t + p.errorf("expected type name or literal, got %s", scanner.TokenString(p.tok)) + return nil } const ( @@ -700,29 +778,36 @@ func lookupBuiltinType(typ int) types.Type { }[typ] } -// Type = "<" "type" ( "-" int | int [ TypeDefinition ] ) ">" . -func (p *parser) parseType(pkg *types.Package) (t types.Type) { +// Type = "<" "type" ( "-" int | int [ TypeSpec ] ) ">" . +// +// parseType updates the type map to t for all type numbers n. +// +func (p *parser) parseType(pkg *types.Package, n ...int) (t types.Type) { p.expect('<') p.expectKeyword("type") switch p.tok { case scanner.Int: - n := p.parseInt() - + n1 := p.parseInt() if p.tok == '>' { - t = p.typeMap[int(n)] + t = p.typeList[n1] + if t == reserved { + p.errorf("invalid type cycle, type %d not yet defined", n1) + } + p.update(t, n) } else { - t = p.parseTypeDefinition(pkg, int(n)) + p.reserve(n1) + t = p.parseTypeSpec(pkg, append(n, n1)) } case '-': p.next() - n := p.parseInt() - t = lookupBuiltinType(int(n)) + n1 := p.parseInt() + t = lookupBuiltinType(n1) + p.update(t, n) default: p.errorf("expected type number, got %s (%q)", scanner.TokenString(p.tok), p.lit) - return nil } p.expect('>') @@ -735,7 +820,7 @@ func (p *parser) parsePackageInit() PackageInit { initfunc := p.parseUnquotedString() priority := -1 if p.version == "v1" { - priority = int(p.parseInt()) + priority = p.parseInt() } return PackageInit{Name: name, InitFunc: initfunc, Priority: priority} } @@ -781,7 +866,7 @@ func (p *parser) parseInitDataDirective() { case "priority": p.next() - p.initdata.Priority = int(p.parseInt()) + p.initdata.Priority = p.parseInt() p.expect(';') case "init": @@ -795,8 +880,8 @@ func (p *parser) parseInitDataDirective() { p.next() // The graph data is thrown away for now. for p.tok != ';' && p.tok != scanner.EOF { - p.parseInt() - p.parseInt() + p.parseInt64() + p.parseInt64() } p.expect(';') @@ -898,7 +983,7 @@ func (p *parser) parsePackage() *types.Package { for p.tok != scanner.EOF { p.parseDirective() } - for _, typ := range p.typeMap { + for _, typ := range p.typeList { if it, ok := typ.(*types.Interface); ok { it.Complete() } diff --git a/src/go/internal/gccgoimporter/testdata/alias.gox b/src/go/internal/gccgoimporter/testdata/alias.gox deleted file mode 100644 index ced7d84c4f..0000000000 --- a/src/go/internal/gccgoimporter/testdata/alias.gox +++ /dev/null @@ -1,4 +0,0 @@ -v1; -package alias; -pkgpath alias; -type <type 115 "I1" <type 116 interface { M1 (? <type 117 "IntAlias2" = <type 118 "IntAlias" = <type 119 "Int" <type -11>>>>) < type 114>; M2 () <type 1>; }>>; diff --git a/src/go/internal/gccgoimporter/testdata/aliases.go b/src/go/internal/gccgoimporter/testdata/aliases.go new file mode 100644 index 0000000000..cfb59b3e31 --- /dev/null +++ b/src/go/internal/gccgoimporter/testdata/aliases.go @@ -0,0 +1,65 @@ +package aliases + +type ( + T0 [10]int + T1 []byte + T2 struct { + x int + } + T3 interface { + m() T2 + } + T4 func(int, T0) chan T2 +) + +// basic aliases +type ( + Ai = int + A0 = T0 + A1 = T1 + A2 = T2 + A3 = T3 + A4 = T4 + + A10 = [10]int + A11 = []byte + A12 = struct { + x int + } + A13 = interface { + m() A2 + } + A14 = func(int, A0) chan A2 +) + +// alias receiver types +func (T0) m1() {} +func (A0) m2() {} + +// alias receiver types (long type declaration chains) +type ( + V0 = V1 + V1 = (V2) + V2 = (V3) + V3 = T0 +) + +func (V1) n() {} + +// cycles +type C0 struct { + f1 C1 + f2 C2 +} + +type ( + C1 *C0 + C2 = C1 +) + +type ( + C5 struct { + f *C6 + } + C6 = C5 +) diff --git a/src/go/internal/gccgoimporter/testdata/aliases.gox b/src/go/internal/gccgoimporter/testdata/aliases.gox new file mode 100644 index 0000000000..2428c06874 --- /dev/null +++ b/src/go/internal/gccgoimporter/testdata/aliases.gox @@ -0,0 +1,33 @@ +v2; +package aliases; +prefix go; +package aliases go.aliases go.aliases; +type <type 1 "A0" = <type 2 "T0" <type 3 [10 ] <type -11>> + func (? <esc:0x1> <type 2>) .go.aliases.m1 (); + func (? <esc:0x1> <type 1>) .go.aliases.m2 (); + func (? <esc:0x1> <type 4 "V1" = <type 5 "V2" = <type 6 "V3" = <type 2>>>>) .go.aliases.n (); +>>; +type <type 7 "A1" = <type 8 "T1" <type 9 [] <type -20>>>>; +type <type 10 "A10" = <type 11 [10 ] <type -11>>>; +type <type 12 "A11" = <type 13 [] <type -20>>>; +type <type 14 "A12" = <type 15 struct { .go.aliases.x <type -11>; }>>; +type <type 16 "A13" = <type 17 interface { .go.aliases.m () <type 18 "A2" = <type 19 "T2" <type 20 struct { .go.aliases.x <type -11>; }>>>; }>>; +type <type 21 "A14" = <type 22 (? <type -11>, ? <type 1>) <type 23 chan <type 18>>>>; +type <type 18>; +type <type 24 "A3" = <type 25 "T3" <type 26 interface { .go.aliases.m () <type 19>; }>>>; +type <type 27 "A4" = <type 28 "T4" <type 29 (? <type -11>, ? <type 2>) <type 30 chan <type 19>>>>>; +type <type 31 "Ai" = <type -11>>; +type <type 32 "C0" <type 33 struct { .go.aliases.f1 <type 34 "C1" <type 35 *<type 32>>>; .go.aliases.f2 <type 36 "C2" = <type 34>>; }>>; +type <type 34>; +type <type 36>; +type <type 37 "C5" <type 38 struct { .go.aliases.f <type 39 *<type 40 "C6" = <type 37>>>; }>>; +type <type 40>; +type <type 2>; +type <type 8>; +type <type 19>; +type <type 25>; +type <type 28>; +type <type 41 "V0" = <type 4>>; +type <type 4>; +type <type 5>; +type <type 6>; diff --git a/src/go/internal/gccgoimporter/testdata/issue27856.go b/src/go/internal/gccgoimporter/testdata/issue27856.go new file mode 100644 index 0000000000..bf361e1cd8 --- /dev/null +++ b/src/go/internal/gccgoimporter/testdata/issue27856.go @@ -0,0 +1,9 @@ +package lib + +type M struct { + E E +} +type F struct { + _ *M +} +type E = F diff --git a/src/go/internal/gccgoimporter/testdata/issue27856.gox b/src/go/internal/gccgoimporter/testdata/issue27856.gox new file mode 100644 index 0000000000..6665e64021 --- /dev/null +++ b/src/go/internal/gccgoimporter/testdata/issue27856.gox @@ -0,0 +1,9 @@ +v2; +package main; +pkgpath main; +import runtime runtime "runtime"; +init runtime runtime..import sys runtime_internal_sys..import; +init_graph 0 1; +type <type 1 "E" = <type 2 "F" <type 3 struct { .main._ <type 4 *<type 5 "M" <type 6 struct { E <type 1>; }>>>; }>>>; +type <type 2>; +type <type 5>; diff --git a/src/go/printer/example_test.go b/src/go/printer/example_test.go index e570040ba1..30816931a8 100644 --- a/src/go/printer/example_test.go +++ b/src/go/printer/example_test.go @@ -48,7 +48,7 @@ func ExampleFprint() { // and trim leading and trailing white space. s := buf.String() s = s[1 : len(s)-1] - s = strings.TrimSpace(strings.Replace(s, "\n\t", "\n", -1)) + s = strings.TrimSpace(strings.ReplaceAll(s, "\n\t", "\n")) // Print the cleaned-up body text to stdout. fmt.Println(s) @@ -61,7 +61,7 @@ func ExampleFprint() { // // s := buf.String() // s = s[1 : len(s)-1] - // s = strings.TrimSpace(strings.Replace(s, "\n\t", "\n", -1)) + // s = strings.TrimSpace(strings.ReplaceAll(s, "\n\t", "\n")) // // fmt.Println(s) } diff --git a/src/go/token/position.go b/src/go/token/position.go index 241133fe26..3f5a390078 100644 --- a/src/go/token/position.go +++ b/src/go/token/position.go @@ -146,7 +146,7 @@ func (f *File) AddLine(offset int) { // MergeLine will panic if given an invalid line number. // func (f *File) MergeLine(line int) { - if line <= 0 { + if line < 1 { panic("illegal line number (line numbering starts at 1)") } f.mutex.Lock() @@ -209,6 +209,21 @@ func (f *File) SetLinesForContent(content []byte) { f.mutex.Unlock() } +// LineStart returns the Pos value of the start of the specified line. +// It ignores any alternative positions set using AddLineColumnInfo. +// LineStart panics if the 1-based line number is invalid. +func (f *File) LineStart(line int) Pos { + if line < 1 { + panic("illegal line number (line numbering starts at 1)") + } + f.mutex.Lock() + defer f.mutex.Unlock() + if line > len(f.lines) { + panic("illegal line number") + } + return Pos(f.base + f.lines[line-1]) +} + // A lineInfo object describes alternative file, line, and column // number information (such as provided via a //line directive) // for a given file offset. diff --git a/src/go/token/position_test.go b/src/go/token/position_test.go index 63984bc872..7d465dffa6 100644 --- a/src/go/token/position_test.go +++ b/src/go/token/position_test.go @@ -324,3 +324,18 @@ done checkPos(t, "3. Position", got3, want) } } + +func TestLineStart(t *testing.T) { + const src = "one\ntwo\nthree\n" + fset := NewFileSet() + f := fset.AddFile("input", -1, len(src)) + f.SetLinesForContent([]byte(src)) + + for line := 1; line <= 3; line++ { + pos := f.LineStart(line) + position := fset.Position(pos) + if position.Line != line || position.Column != 1 { + t.Errorf("LineStart(%d) returned wrong pos %d: %s", line, pos, position) + } + } +} diff --git a/src/go/types/api.go b/src/go/types/api.go index fcefddf488..b1fcb2d10b 100644 --- a/src/go/types/api.go +++ b/src/go/types/api.go @@ -180,7 +180,7 @@ type Info struct { // // *ast.ImportSpec *PkgName for imports without renames // *ast.CaseClause type-specific *Var for each type switch case clause (incl. default) - // *ast.Field anonymous parameter *Var + // *ast.Field anonymous parameter *Var (incl. unnamed results) // Implicits map[ast.Node]Object @@ -240,7 +240,7 @@ func (info *Info) TypeOf(e ast.Expr) Type { // or nil if not found. // // If id is an embedded struct field, ObjectOf returns the field (*Var) -// it uses, not the type (*TypeName) it defines. +// it defines, not the type (*TypeName) it uses. // // Precondition: the Uses and Defs maps are populated. // diff --git a/src/go/types/decl.go b/src/go/types/decl.go index d37a460a4e..0ff1fb058b 100644 --- a/src/go/types/decl.go +++ b/src/go/types/decl.go @@ -65,7 +65,7 @@ func objPathString(path []Object) string { } // objDecl type-checks the declaration of obj in its respective (file) context. -// See check.typ for the details on def and path. +// For the meaning of def, see Checker.definedType, in typexpr.go. func (check *Checker) objDecl(obj Object, def *Named) { if trace { check.trace(obj.Pos(), "-- checking %s %s (objPath = %s)", obj.color(), obj, objPathString(check.objPath)) @@ -140,20 +140,12 @@ func (check *Checker) objDecl(obj Object, def *Named) { // order code. switch obj := obj.(type) { case *Const: - if check.typeCycle(obj) { - obj.typ = Typ[Invalid] - break - } - if obj.typ == nil { + if check.typeCycle(obj) || obj.typ == nil { obj.typ = Typ[Invalid] } case *Var: - if check.typeCycle(obj) { - obj.typ = Typ[Invalid] - break - } - if obj.typ == nil { + if check.typeCycle(obj) || obj.typ == nil { obj.typ = Typ[Invalid] } diff --git a/src/go/types/example_test.go b/src/go/types/example_test.go index 2a2fb3fc59..492127bbab 100644 --- a/src/go/types/example_test.go +++ b/src/go/types/example_test.go @@ -51,6 +51,7 @@ type Celsius float64 func (c Celsius) String() string { return fmt.Sprintf("%g°C", c) } func FToC(f float64) Celsius { return Celsius(f - 32 / 9 * 5) } const Boiling Celsius = 100 +func Unused() { {}; {{ var x int; _ = x }} } // make sure empty block scopes get printed `}, } { f, err := parser.ParseFile(fset, file.name, file.input, 0) @@ -81,23 +82,33 @@ const Boiling Celsius = 100 // . const temperature.Boiling temperature.Celsius // . type temperature.Celsius float64 // . func temperature.FToC(f float64) temperature.Celsius + // . func temperature.Unused() // . func temperature.main() - // // . main.go scope { // . . package fmt - // // . . function scope { // . . . var freezing temperature.Celsius - // . . }. } + // . . } + // . } // . celsius.go scope { // . . package fmt - // // . . function scope { // . . . var c temperature.Celsius // . . } // . . function scope { // . . . var f float64 - // . . }. }} + // . . } + // . . function scope { + // . . . block scope { + // . . . } + // . . . block scope { + // . . . . block scope { + // . . . . . var x int + // . . . . } + // . . . } + // . . } + // . } + // } } // ExampleMethodSet prints the method sets of various types. diff --git a/src/go/types/expr.go b/src/go/types/expr.go index c65c9e7681..fc4de98eb7 100644 --- a/src/go/types/expr.go +++ b/src/go/types/expr.go @@ -1010,7 +1010,7 @@ func (check *Checker) exprInternal(x *operand, e ast.Expr, hint Type) exprKind { goto Error // error was reported before case *ast.Ident: - check.ident(x, e, nil) + check.ident(x, e, nil, false) case *ast.Ellipsis: // ellipses are handled explicitly where they are legal diff --git a/src/go/types/scope.go b/src/go/types/scope.go index 39e42d758a..839a60db2e 100644 --- a/src/go/types/scope.go +++ b/src/go/types/scope.go @@ -161,13 +161,8 @@ func (s *Scope) WriteTo(w io.Writer, n int, recurse bool) { const ind = ". " indn := strings.Repeat(ind, n) - fmt.Fprintf(w, "%s%s scope %p {", indn, s.comment, s) - if len(s.elems) == 0 { - fmt.Fprintf(w, "}\n") - return - } + fmt.Fprintf(w, "%s%s scope %p {\n", indn, s.comment, s) - fmt.Fprintln(w) indn1 := indn + ind for _, name := range s.Names() { fmt.Fprintf(w, "%s%s\n", indn1, s.elems[name]) @@ -175,12 +170,11 @@ func (s *Scope) WriteTo(w io.Writer, n int, recurse bool) { if recurse { for _, s := range s.children { - fmt.Fprintln(w) s.WriteTo(w, n+1, recurse) } } - fmt.Fprintf(w, "%s}", indn) + fmt.Fprintf(w, "%s}\n", indn) } // String returns a string representation of the scope, for debugging. diff --git a/src/go/types/sizes.go b/src/go/types/sizes.go index 7b5410167f..f890c30377 100644 --- a/src/go/types/sizes.go +++ b/src/go/types/sizes.go @@ -169,6 +169,7 @@ var gcArchSizes = map[string]*StdSizes{ "ppc64le": {8, 8}, "riscv64": {8, 8}, "s390x": {8, 8}, + "sparc64": {8, 8}, "wasm": {8, 8}, // When adding more architectures here, // update the doc string of SizesFor below. @@ -179,7 +180,7 @@ var gcArchSizes = map[string]*StdSizes{ // // Supported architectures for compiler "gc": // "386", "arm", "arm64", "amd64", "amd64p32", "mips", "mipsle", -// "mips64", "mips64le", "ppc64", "ppc64le", "riscv64", "s390x", "wasm". +// "mips64", "mips64le", "ppc64", "ppc64le", "riscv64", "s390x", "sparc64", "wasm". func SizesFor(compiler, arch string) Sizes { if compiler != "gc" { return nil diff --git a/src/go/types/testdata/cycles5.src b/src/go/types/testdata/cycles5.src index 9c2822e738..aa6528a631 100644 --- a/src/go/types/testdata/cycles5.src +++ b/src/go/types/testdata/cycles5.src @@ -162,20 +162,29 @@ func makeArray() (res T12) { return } var r /* ERROR cycle */ = newReader() func newReader() r -// variations of the theme of #8699 amd #20770 +// variations of the theme of #8699 and #20770 var arr /* ERROR cycle */ = f() func f() [len(arr)]int -// TODO(gri) here we should only get one error -func ff /* ERROR cycle */ (ff /* ERROR not a type */ ) +// issue #25790 +func ff(ff /* ERROR not a type */ ) +func gg((gg /* ERROR not a type */ )) type T13 /* ERROR cycle */ [len(b13)]int var b13 T13 -func g /* ERROR cycle */ () [unsafe.Sizeof(x)]int -var x = g +func g1() [unsafe.Sizeof(g1)]int +func g2() [unsafe.Sizeof(x2)]int +var x2 = g2 -func h /* ERROR cycle */ () [h /* ERROR no value */ ()[0]]int { panic(0) } +// verify that we get the correct sizes for the functions above +// (note: assert is statically evaluated in go/types test mode) +func init() { + assert(unsafe.Sizeof(g1) == 8) + assert(unsafe.Sizeof(x2) == 8) +} + +func h() [h /* ERROR no value */ ()[0]]int { panic(0) } var c14 /* ERROR cycle */ T14 type T14 [uintptr(unsafe.Sizeof(&c14))]byte diff --git a/src/go/types/testdata/decls0.src b/src/go/types/testdata/decls0.src index 162dfeda04..e75216172b 100644 --- a/src/go/types/testdata/decls0.src +++ b/src/go/types/testdata/decls0.src @@ -183,11 +183,11 @@ type ( ) // cycles in function/method declarations -// (test cases for issue 5217 and variants) -func f1 /* ERROR cycle */ (x f1 /* ERROR "not a type" */ ) {} -func f2 /* ERROR cycle */ (x *f2 /* ERROR "not a type" */ ) {} -func f3 /* ERROR cycle */ () (x f3 /* ERROR "not a type" */ ) { return } -func f4 /* ERROR cycle */ () (x *f4 /* ERROR "not a type" */ ) { return } +// (test cases for issues #5217, #25790 and variants) +func f1(x f1 /* ERROR "not a type" */ ) {} +func f2(x *f2 /* ERROR "not a type" */ ) {} +func f3() (x f3 /* ERROR "not a type" */ ) { return } +func f4() (x *f4 /* ERROR "not a type" */ ) { return } func (S0) m1(x S0.m1 /* ERROR "field or method" */ ) {} func (S0) m2(x *S0.m2 /* ERROR "field or method" */ ) {} diff --git a/src/go/types/typexpr.go b/src/go/types/typexpr.go index 83848099c2..12c5c7b0a5 100644 --- a/src/go/types/typexpr.go +++ b/src/go/types/typexpr.go @@ -16,9 +16,10 @@ import ( // ident type-checks identifier e and initializes x with the value or type of e. // If an error occurred, x.mode is set to invalid. -// For the meaning of def, see check.typExpr, below. +// For the meaning of def, see Checker.definedType, below. +// If wantType is set, the identifier e is expected to denote a type. // -func (check *Checker) ident(x *operand, e *ast.Ident, def *Named) { +func (check *Checker) ident(x *operand, e *ast.Ident, def *Named, wantType bool) { x.mode = invalid x.expr = e @@ -35,8 +36,19 @@ func (check *Checker) ident(x *operand, e *ast.Ident, def *Named) { } check.recordUse(e, obj) - check.objDecl(obj, def) + // Type-check the object. + // Only call Checker.objDecl if the object doesn't have a type yet + // (in which case we must actually determine it) or the object is a + // TypeName and we also want a type (in which case we might detect + // a cycle which needs to be reported). Otherwise we can skip the + // call and avoid a possible cycle error in favor of the more + // informative "not a type/value" error that this function's caller + // will issue (see issue #25790). typ := obj.Type() + if _, gotType := obj.(*TypeName); typ == nil || gotType && wantType { + check.objDecl(obj, def) + typ = obj.Type() // type must have been assigned by Checker.objDecl + } assert(typ != nil) // The object may be dot-imported: If so, remove its package from @@ -215,7 +227,7 @@ func (check *Checker) typInternal(e ast.Expr, def *Named) Type { case *ast.Ident: var x operand - check.ident(&x, e, def) + check.ident(&x, e, def, true) switch x.mode { case typexpr: diff --git a/src/html/template/js.go b/src/html/template/js.go index 33a18b4186..2291f47c33 100644 --- a/src/html/template/js.go +++ b/src/html/template/js.go @@ -172,7 +172,7 @@ func jsValEscaper(args ...interface{}) string { // turning into // x//* error marshaling y: // second line of error message */null - return fmt.Sprintf(" /* %s */null ", strings.Replace(err.Error(), "*/", "* /", -1)) + return fmt.Sprintf(" /* %s */null ", strings.ReplaceAll(err.Error(), "*/", "* /")) } // TODO: maybe post-process output to prevent it from containing diff --git a/src/html/template/url.go b/src/html/template/url.go index f0516300de..8a4f727e50 100644 --- a/src/html/template/url.go +++ b/src/html/template/url.go @@ -156,7 +156,7 @@ func srcsetFilterAndEscaper(args ...interface{}) string { s = b.String() } // Additionally, commas separate one source from another. - return strings.Replace(s, ",", "%2c", -1) + return strings.ReplaceAll(s, ",", "%2c") } var b bytes.Buffer diff --git a/src/image/draw/draw.go b/src/image/draw/draw.go index 977d7c5221..3ff1828dc0 100644 --- a/src/image/draw/draw.go +++ b/src/image/draw/draw.go @@ -309,23 +309,20 @@ func drawCopyOver(dst *image.RGBA, r image.Rectangle, src *image.RGBA, sp image. dpix := dst.Pix[d0:] spix := src.Pix[s0:] for i := i0; i != i1; i += idelta { - sr := uint32(spix[i+0]) * 0x101 - sg := uint32(spix[i+1]) * 0x101 - sb := uint32(spix[i+2]) * 0x101 - sa := uint32(spix[i+3]) * 0x101 - - dr := &dpix[i+0] - dg := &dpix[i+1] - db := &dpix[i+2] - da := &dpix[i+3] + s := spix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + sr := uint32(s[0]) * 0x101 + sg := uint32(s[1]) * 0x101 + sb := uint32(s[2]) * 0x101 + sa := uint32(s[3]) * 0x101 // The 0x101 is here for the same reason as in drawRGBA. a := (m - sa) * 0x101 - *dr = uint8((uint32(*dr)*a/m + sr) >> 8) - *dg = uint8((uint32(*dg)*a/m + sg) >> 8) - *db = uint8((uint32(*db)*a/m + sb) >> 8) - *da = uint8((uint32(*da)*a/m + sa) >> 8) + d := dpix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + d[0] = uint8((uint32(d[0])*a/m + sr) >> 8) + d[1] = uint8((uint32(d[1])*a/m + sg) >> 8) + d[2] = uint8((uint32(d[2])*a/m + sb) >> 8) + d[3] = uint8((uint32(d[3])*a/m + sa) >> 8) } d0 += ddelta s0 += sdelta @@ -372,23 +369,25 @@ func drawNRGBAOver(dst *image.RGBA, r image.Rectangle, src *image.NRGBA, sp imag for i, si := i0, si0; i < i1; i, si = i+4, si+4 { // Convert from non-premultiplied color to pre-multiplied color. - sa := uint32(spix[si+3]) * 0x101 - sr := uint32(spix[si+0]) * sa / 0xff - sg := uint32(spix[si+1]) * sa / 0xff - sb := uint32(spix[si+2]) * sa / 0xff + s := spix[si : si+4 : si+4] // Small cap improves performance, see https://golang.org/issue/27857 + sa := uint32(s[3]) * 0x101 + sr := uint32(s[0]) * sa / 0xff + sg := uint32(s[1]) * sa / 0xff + sb := uint32(s[2]) * sa / 0xff - dr := uint32(dpix[i+0]) - dg := uint32(dpix[i+1]) - db := uint32(dpix[i+2]) - da := uint32(dpix[i+3]) + d := dpix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + dr := uint32(d[0]) + dg := uint32(d[1]) + db := uint32(d[2]) + da := uint32(d[3]) // The 0x101 is here for the same reason as in drawRGBA. a := (m - sa) * 0x101 - dpix[i+0] = uint8((dr*a/m + sr) >> 8) - dpix[i+1] = uint8((dg*a/m + sg) >> 8) - dpix[i+2] = uint8((db*a/m + sb) >> 8) - dpix[i+3] = uint8((da*a/m + sa) >> 8) + d[0] = uint8((dr*a/m + sr) >> 8) + d[1] = uint8((dg*a/m + sg) >> 8) + d[2] = uint8((db*a/m + sb) >> 8) + d[3] = uint8((da*a/m + sa) >> 8) } } } @@ -407,15 +406,17 @@ func drawNRGBASrc(dst *image.RGBA, r image.Rectangle, src *image.NRGBA, sp image for i, si := i0, si0; i < i1; i, si = i+4, si+4 { // Convert from non-premultiplied color to pre-multiplied color. - sa := uint32(spix[si+3]) * 0x101 - sr := uint32(spix[si+0]) * sa / 0xff - sg := uint32(spix[si+1]) * sa / 0xff - sb := uint32(spix[si+2]) * sa / 0xff + s := spix[si : si+4 : si+4] // Small cap improves performance, see https://golang.org/issue/27857 + sa := uint32(s[3]) * 0x101 + sr := uint32(s[0]) * sa / 0xff + sg := uint32(s[1]) * sa / 0xff + sb := uint32(s[2]) * sa / 0xff - dpix[i+0] = uint8(sr >> 8) - dpix[i+1] = uint8(sg >> 8) - dpix[i+2] = uint8(sb >> 8) - dpix[i+3] = uint8(sa >> 8) + d := dpix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + d[0] = uint8(sr >> 8) + d[1] = uint8(sg >> 8) + d[2] = uint8(sb >> 8) + d[3] = uint8(sa >> 8) } } } @@ -434,10 +435,11 @@ func drawGray(dst *image.RGBA, r image.Rectangle, src *image.Gray, sp image.Poin for i, si := i0, si0; i < i1; i, si = i+4, si+1 { p := spix[si] - dpix[i+0] = p - dpix[i+1] = p - dpix[i+2] = p - dpix[i+3] = 255 + d := dpix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + d[0] = p + d[1] = p + d[2] = p + d[3] = 255 } } } @@ -455,9 +457,10 @@ func drawCMYK(dst *image.RGBA, r image.Rectangle, src *image.CMYK, sp image.Poin spix := src.Pix[sy*src.Stride:] for i, si := i0, si0; i < i1; i, si = i+4, si+4 { - dpix[i+0], dpix[i+1], dpix[i+2] = - color.CMYKToRGB(spix[si+0], spix[si+1], spix[si+2], spix[si+3]) - dpix[i+3] = 255 + s := spix[si : si+4 : si+4] // Small cap improves performance, see https://golang.org/issue/27857 + d := dpix[i : i+4 : i+4] + d[0], d[1], d[2] = color.CMYKToRGB(s[0], s[1], s[2], s[3]) + d[3] = 255 } } } @@ -475,18 +478,14 @@ func drawGlyphOver(dst *image.RGBA, r image.Rectangle, src *image.Uniform, mask } ma |= ma << 8 - dr := &dst.Pix[i+0] - dg := &dst.Pix[i+1] - db := &dst.Pix[i+2] - da := &dst.Pix[i+3] - // The 0x101 is here for the same reason as in drawRGBA. a := (m - (sa * ma / m)) * 0x101 - *dr = uint8((uint32(*dr)*a + sr*ma) / m >> 8) - *dg = uint8((uint32(*dg)*a + sg*ma) / m >> 8) - *db = uint8((uint32(*db)*a + sb*ma) / m >> 8) - *da = uint8((uint32(*da)*a + sa*ma) / m >> 8) + d := dst.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + d[0] = uint8((uint32(d[0])*a + sr*ma) / m >> 8) + d[1] = uint8((uint32(d[1])*a + sg*ma) / m >> 8) + d[2] = uint8((uint32(d[2])*a + sb*ma) / m >> 8) + d[3] = uint8((uint32(d[3])*a + sa*ma) / m >> 8) } i0 += dst.Stride i1 += dst.Stride @@ -518,11 +517,12 @@ func drawRGBA(dst *image.RGBA, r image.Rectangle, src image.Image, sp image.Poin _, _, _, ma = mask.At(mx, my).RGBA() } sr, sg, sb, sa := src.At(sx, sy).RGBA() + d := dst.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 if op == Over { - dr := uint32(dst.Pix[i+0]) - dg := uint32(dst.Pix[i+1]) - db := uint32(dst.Pix[i+2]) - da := uint32(dst.Pix[i+3]) + dr := uint32(d[0]) + dg := uint32(d[1]) + db := uint32(d[2]) + da := uint32(d[3]) // dr, dg, db and da are all 8-bit color at the moment, ranging in [0,255]. // We work in 16-bit color, and so would normally do: @@ -532,16 +532,16 @@ func drawRGBA(dst *image.RGBA, r image.Rectangle, src image.Image, sp image.Poin // This yields the same result, but is fewer arithmetic operations. a := (m - (sa * ma / m)) * 0x101 - dst.Pix[i+0] = uint8((dr*a + sr*ma) / m >> 8) - dst.Pix[i+1] = uint8((dg*a + sg*ma) / m >> 8) - dst.Pix[i+2] = uint8((db*a + sb*ma) / m >> 8) - dst.Pix[i+3] = uint8((da*a + sa*ma) / m >> 8) + d[0] = uint8((dr*a + sr*ma) / m >> 8) + d[1] = uint8((dg*a + sg*ma) / m >> 8) + d[2] = uint8((db*a + sb*ma) / m >> 8) + d[3] = uint8((da*a + sa*ma) / m >> 8) } else { - dst.Pix[i+0] = uint8(sr * ma / m >> 8) - dst.Pix[i+1] = uint8(sg * ma / m >> 8) - dst.Pix[i+2] = uint8(sb * ma / m >> 8) - dst.Pix[i+3] = uint8(sa * ma / m >> 8) + d[0] = uint8(sr * ma / m >> 8) + d[1] = uint8(sg * ma / m >> 8) + d[2] = uint8(sb * ma / m >> 8) + d[3] = uint8(sa * ma / m >> 8) } } i0 += dy * dst.Stride diff --git a/src/image/format.go b/src/image/format.go index 3668de4e68..a53b8f9b55 100644 --- a/src/image/format.go +++ b/src/image/format.go @@ -8,6 +8,8 @@ import ( "bufio" "errors" "io" + "sync" + "sync/atomic" ) // ErrFormat indicates that decoding encountered an unknown format. @@ -21,7 +23,10 @@ type format struct { } // Formats is the list of registered formats. -var formats []format +var ( + formatsMu sync.Mutex + atomicFormats atomic.Value +) // RegisterFormat registers an image format for use by Decode. // Name is the name of the format, like "jpeg" or "png". @@ -30,7 +35,10 @@ var formats []format // Decode is the function that decodes the encoded image. // DecodeConfig is the function that decodes just its configuration. func RegisterFormat(name, magic string, decode func(io.Reader) (Image, error), decodeConfig func(io.Reader) (Config, error)) { - formats = append(formats, format{name, magic, decode, decodeConfig}) + formatsMu.Lock() + formats, _ := atomicFormats.Load().([]format) + atomicFormats.Store(append(formats, format{name, magic, decode, decodeConfig})) + formatsMu.Unlock() } // A reader is an io.Reader that can also peek ahead. @@ -62,6 +70,7 @@ func match(magic string, b []byte) bool { // Sniff determines the format of r's data. func sniff(r reader) format { + formats, _ := atomicFormats.Load().([]format) for _, f := range formats { b, err := r.Peek(len(f.magic)) if err == nil && match(f.magic, b) { diff --git a/src/image/image.go b/src/image/image.go index bebb9f70fa..ffd6de7383 100644 --- a/src/image/image.go +++ b/src/image/image.go @@ -80,7 +80,8 @@ func (p *RGBA) RGBAAt(x, y int) color.RGBA { return color.RGBA{} } i := p.PixOffset(x, y) - return color.RGBA{p.Pix[i+0], p.Pix[i+1], p.Pix[i+2], p.Pix[i+3]} + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + return color.RGBA{s[0], s[1], s[2], s[3]} } // PixOffset returns the index of the first element of Pix that corresponds to @@ -95,10 +96,11 @@ func (p *RGBA) Set(x, y int, c color.Color) { } i := p.PixOffset(x, y) c1 := color.RGBAModel.Convert(c).(color.RGBA) - p.Pix[i+0] = c1.R - p.Pix[i+1] = c1.G - p.Pix[i+2] = c1.B - p.Pix[i+3] = c1.A + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = c1.R + s[1] = c1.G + s[2] = c1.B + s[3] = c1.A } func (p *RGBA) SetRGBA(x, y int, c color.RGBA) { @@ -106,10 +108,11 @@ func (p *RGBA) SetRGBA(x, y int, c color.RGBA) { return } i := p.PixOffset(x, y) - p.Pix[i+0] = c.R - p.Pix[i+1] = c.G - p.Pix[i+2] = c.B - p.Pix[i+3] = c.A + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = c.R + s[1] = c.G + s[2] = c.B + s[3] = c.A } // SubImage returns an image representing the portion of the image p visible @@ -179,11 +182,12 @@ func (p *RGBA64) RGBA64At(x, y int) color.RGBA64 { return color.RGBA64{} } i := p.PixOffset(x, y) + s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857 return color.RGBA64{ - uint16(p.Pix[i+0])<<8 | uint16(p.Pix[i+1]), - uint16(p.Pix[i+2])<<8 | uint16(p.Pix[i+3]), - uint16(p.Pix[i+4])<<8 | uint16(p.Pix[i+5]), - uint16(p.Pix[i+6])<<8 | uint16(p.Pix[i+7]), + uint16(s[0])<<8 | uint16(s[1]), + uint16(s[2])<<8 | uint16(s[3]), + uint16(s[4])<<8 | uint16(s[5]), + uint16(s[6])<<8 | uint16(s[7]), } } @@ -199,14 +203,15 @@ func (p *RGBA64) Set(x, y int, c color.Color) { } i := p.PixOffset(x, y) c1 := color.RGBA64Model.Convert(c).(color.RGBA64) - p.Pix[i+0] = uint8(c1.R >> 8) - p.Pix[i+1] = uint8(c1.R) - p.Pix[i+2] = uint8(c1.G >> 8) - p.Pix[i+3] = uint8(c1.G) - p.Pix[i+4] = uint8(c1.B >> 8) - p.Pix[i+5] = uint8(c1.B) - p.Pix[i+6] = uint8(c1.A >> 8) - p.Pix[i+7] = uint8(c1.A) + s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = uint8(c1.R >> 8) + s[1] = uint8(c1.R) + s[2] = uint8(c1.G >> 8) + s[3] = uint8(c1.G) + s[4] = uint8(c1.B >> 8) + s[5] = uint8(c1.B) + s[6] = uint8(c1.A >> 8) + s[7] = uint8(c1.A) } func (p *RGBA64) SetRGBA64(x, y int, c color.RGBA64) { @@ -214,14 +219,15 @@ func (p *RGBA64) SetRGBA64(x, y int, c color.RGBA64) { return } i := p.PixOffset(x, y) - p.Pix[i+0] = uint8(c.R >> 8) - p.Pix[i+1] = uint8(c.R) - p.Pix[i+2] = uint8(c.G >> 8) - p.Pix[i+3] = uint8(c.G) - p.Pix[i+4] = uint8(c.B >> 8) - p.Pix[i+5] = uint8(c.B) - p.Pix[i+6] = uint8(c.A >> 8) - p.Pix[i+7] = uint8(c.A) + s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = uint8(c.R >> 8) + s[1] = uint8(c.R) + s[2] = uint8(c.G >> 8) + s[3] = uint8(c.G) + s[4] = uint8(c.B >> 8) + s[5] = uint8(c.B) + s[6] = uint8(c.A >> 8) + s[7] = uint8(c.A) } // SubImage returns an image representing the portion of the image p visible @@ -291,7 +297,8 @@ func (p *NRGBA) NRGBAAt(x, y int) color.NRGBA { return color.NRGBA{} } i := p.PixOffset(x, y) - return color.NRGBA{p.Pix[i+0], p.Pix[i+1], p.Pix[i+2], p.Pix[i+3]} + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + return color.NRGBA{s[0], s[1], s[2], s[3]} } // PixOffset returns the index of the first element of Pix that corresponds to @@ -306,10 +313,11 @@ func (p *NRGBA) Set(x, y int, c color.Color) { } i := p.PixOffset(x, y) c1 := color.NRGBAModel.Convert(c).(color.NRGBA) - p.Pix[i+0] = c1.R - p.Pix[i+1] = c1.G - p.Pix[i+2] = c1.B - p.Pix[i+3] = c1.A + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = c1.R + s[1] = c1.G + s[2] = c1.B + s[3] = c1.A } func (p *NRGBA) SetNRGBA(x, y int, c color.NRGBA) { @@ -317,10 +325,11 @@ func (p *NRGBA) SetNRGBA(x, y int, c color.NRGBA) { return } i := p.PixOffset(x, y) - p.Pix[i+0] = c.R - p.Pix[i+1] = c.G - p.Pix[i+2] = c.B - p.Pix[i+3] = c.A + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = c.R + s[1] = c.G + s[2] = c.B + s[3] = c.A } // SubImage returns an image representing the portion of the image p visible @@ -390,11 +399,12 @@ func (p *NRGBA64) NRGBA64At(x, y int) color.NRGBA64 { return color.NRGBA64{} } i := p.PixOffset(x, y) + s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857 return color.NRGBA64{ - uint16(p.Pix[i+0])<<8 | uint16(p.Pix[i+1]), - uint16(p.Pix[i+2])<<8 | uint16(p.Pix[i+3]), - uint16(p.Pix[i+4])<<8 | uint16(p.Pix[i+5]), - uint16(p.Pix[i+6])<<8 | uint16(p.Pix[i+7]), + uint16(s[0])<<8 | uint16(s[1]), + uint16(s[2])<<8 | uint16(s[3]), + uint16(s[4])<<8 | uint16(s[5]), + uint16(s[6])<<8 | uint16(s[7]), } } @@ -410,14 +420,15 @@ func (p *NRGBA64) Set(x, y int, c color.Color) { } i := p.PixOffset(x, y) c1 := color.NRGBA64Model.Convert(c).(color.NRGBA64) - p.Pix[i+0] = uint8(c1.R >> 8) - p.Pix[i+1] = uint8(c1.R) - p.Pix[i+2] = uint8(c1.G >> 8) - p.Pix[i+3] = uint8(c1.G) - p.Pix[i+4] = uint8(c1.B >> 8) - p.Pix[i+5] = uint8(c1.B) - p.Pix[i+6] = uint8(c1.A >> 8) - p.Pix[i+7] = uint8(c1.A) + s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = uint8(c1.R >> 8) + s[1] = uint8(c1.R) + s[2] = uint8(c1.G >> 8) + s[3] = uint8(c1.G) + s[4] = uint8(c1.B >> 8) + s[5] = uint8(c1.B) + s[6] = uint8(c1.A >> 8) + s[7] = uint8(c1.A) } func (p *NRGBA64) SetNRGBA64(x, y int, c color.NRGBA64) { @@ -425,14 +436,15 @@ func (p *NRGBA64) SetNRGBA64(x, y int, c color.NRGBA64) { return } i := p.PixOffset(x, y) - p.Pix[i+0] = uint8(c.R >> 8) - p.Pix[i+1] = uint8(c.R) - p.Pix[i+2] = uint8(c.G >> 8) - p.Pix[i+3] = uint8(c.G) - p.Pix[i+4] = uint8(c.B >> 8) - p.Pix[i+5] = uint8(c.B) - p.Pix[i+6] = uint8(c.A >> 8) - p.Pix[i+7] = uint8(c.A) + s := p.Pix[i : i+8 : i+8] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = uint8(c.R >> 8) + s[1] = uint8(c.R) + s[2] = uint8(c.G >> 8) + s[3] = uint8(c.G) + s[4] = uint8(c.B >> 8) + s[5] = uint8(c.B) + s[6] = uint8(c.A >> 8) + s[7] = uint8(c.A) } // SubImage returns an image representing the portion of the image p visible @@ -850,7 +862,8 @@ func (p *CMYK) CMYKAt(x, y int) color.CMYK { return color.CMYK{} } i := p.PixOffset(x, y) - return color.CMYK{p.Pix[i+0], p.Pix[i+1], p.Pix[i+2], p.Pix[i+3]} + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + return color.CMYK{s[0], s[1], s[2], s[3]} } // PixOffset returns the index of the first element of Pix that corresponds to @@ -865,10 +878,11 @@ func (p *CMYK) Set(x, y int, c color.Color) { } i := p.PixOffset(x, y) c1 := color.CMYKModel.Convert(c).(color.CMYK) - p.Pix[i+0] = c1.C - p.Pix[i+1] = c1.M - p.Pix[i+2] = c1.Y - p.Pix[i+3] = c1.K + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = c1.C + s[1] = c1.M + s[2] = c1.Y + s[3] = c1.K } func (p *CMYK) SetCMYK(x, y int, c color.CMYK) { @@ -876,10 +890,11 @@ func (p *CMYK) SetCMYK(x, y int, c color.CMYK) { return } i := p.PixOffset(x, y) - p.Pix[i+0] = c.C - p.Pix[i+1] = c.M - p.Pix[i+2] = c.Y - p.Pix[i+3] = c.K + s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857 + s[0] = c.C + s[1] = c.M + s[2] = c.Y + s[3] = c.K } // SubImage returns an image representing the portion of the image p visible diff --git a/src/image/image_test.go b/src/image/image_test.go index 08ba61ea0c..dfd8eb35a8 100644 --- a/src/image/image_test.go +++ b/src/image/image_test.go @@ -22,22 +22,29 @@ func cmp(cm color.Model, c0, c1 color.Color) bool { return r0 == r1 && g0 == g1 && b0 == b1 && a0 == a1 } -func TestImage(t *testing.T) { - testImage := []image{ - NewRGBA(Rect(0, 0, 10, 10)), - NewRGBA64(Rect(0, 0, 10, 10)), - NewNRGBA(Rect(0, 0, 10, 10)), - NewNRGBA64(Rect(0, 0, 10, 10)), - NewAlpha(Rect(0, 0, 10, 10)), - NewAlpha16(Rect(0, 0, 10, 10)), - NewGray(Rect(0, 0, 10, 10)), - NewGray16(Rect(0, 0, 10, 10)), - NewPaletted(Rect(0, 0, 10, 10), color.Palette{ +var testImages = []struct { + name string + image func() image +}{ + {"rgba", func() image { return NewRGBA(Rect(0, 0, 10, 10)) }}, + {"rgba64", func() image { return NewRGBA64(Rect(0, 0, 10, 10)) }}, + {"nrgba", func() image { return NewNRGBA(Rect(0, 0, 10, 10)) }}, + {"nrgba64", func() image { return NewNRGBA64(Rect(0, 0, 10, 10)) }}, + {"alpha", func() image { return NewAlpha(Rect(0, 0, 10, 10)) }}, + {"alpha16", func() image { return NewAlpha16(Rect(0, 0, 10, 10)) }}, + {"gray", func() image { return NewGray(Rect(0, 0, 10, 10)) }}, + {"gray16", func() image { return NewGray16(Rect(0, 0, 10, 10)) }}, + {"paletted", func() image { + return NewPaletted(Rect(0, 0, 10, 10), color.Palette{ Transparent, Opaque, - }), - } - for _, m := range testImage { + }) + }}, +} + +func TestImage(t *testing.T) { + for _, tc := range testImages { + m := tc.image() if !Rect(0, 0, 10, 10).Eq(m.Bounds()) { t.Errorf("%T: want bounds %v, got %v", m, Rect(0, 0, 10, 10), m.Bounds()) continue @@ -111,3 +118,182 @@ func Test16BitsPerColorChannel(t *testing.T) { } } } + +func BenchmarkAt(b *testing.B) { + for _, tc := range testImages { + b.Run(tc.name, func(b *testing.B) { + m := tc.image() + b.ReportAllocs() + b.ResetTimer() + for i := 0; i < b.N; i++ { + m.At(4, 5) + } + }) + } +} + +func BenchmarkSet(b *testing.B) { + c := color.Gray{0xff} + for _, tc := range testImages { + b.Run(tc.name, func(b *testing.B) { + m := tc.image() + b.ReportAllocs() + b.ResetTimer() + for i := 0; i < b.N; i++ { + m.Set(4, 5, c) + } + }) + } +} + +func BenchmarkRGBAAt(b *testing.B) { + m := NewRGBA(Rect(0, 0, 10, 10)) + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.RGBAAt(4, 5) + } +} + +func BenchmarkRGBASetRGBA(b *testing.B) { + m := NewRGBA(Rect(0, 0, 10, 10)) + c := color.RGBA{0xff, 0xff, 0xff, 0x13} + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.SetRGBA(4, 5, c) + } +} + +func BenchmarkRGBA64At(b *testing.B) { + m := NewRGBA64(Rect(0, 0, 10, 10)) + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.RGBA64At(4, 5) + } +} + +func BenchmarkRGBA64SetRGBA64(b *testing.B) { + m := NewRGBA64(Rect(0, 0, 10, 10)) + c := color.RGBA64{0xffff, 0xffff, 0xffff, 0x1357} + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.SetRGBA64(4, 5, c) + } +} + +func BenchmarkNRGBAAt(b *testing.B) { + m := NewNRGBA(Rect(0, 0, 10, 10)) + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.NRGBAAt(4, 5) + } +} + +func BenchmarkNRGBASetNRGBA(b *testing.B) { + m := NewNRGBA(Rect(0, 0, 10, 10)) + c := color.NRGBA{0xff, 0xff, 0xff, 0x13} + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.SetNRGBA(4, 5, c) + } +} + +func BenchmarkNRGBA64At(b *testing.B) { + m := NewNRGBA64(Rect(0, 0, 10, 10)) + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.NRGBA64At(4, 5) + } +} + +func BenchmarkNRGBA64SetNRGBA64(b *testing.B) { + m := NewNRGBA64(Rect(0, 0, 10, 10)) + c := color.NRGBA64{0xffff, 0xffff, 0xffff, 0x1357} + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.SetNRGBA64(4, 5, c) + } +} + +func BenchmarkAlphaAt(b *testing.B) { + m := NewAlpha(Rect(0, 0, 10, 10)) + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.AlphaAt(4, 5) + } +} + +func BenchmarkAlphaSetAlpha(b *testing.B) { + m := NewAlpha(Rect(0, 0, 10, 10)) + c := color.Alpha{0x13} + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.SetAlpha(4, 5, c) + } +} + +func BenchmarkAlpha16At(b *testing.B) { + m := NewAlpha16(Rect(0, 0, 10, 10)) + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.Alpha16At(4, 5) + } +} + +func BenchmarkAlphaSetAlpha16(b *testing.B) { + m := NewAlpha16(Rect(0, 0, 10, 10)) + c := color.Alpha16{0x13} + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.SetAlpha16(4, 5, c) + } +} + +func BenchmarkGrayAt(b *testing.B) { + m := NewGray(Rect(0, 0, 10, 10)) + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.GrayAt(4, 5) + } +} + +func BenchmarkGraySetGray(b *testing.B) { + m := NewGray(Rect(0, 0, 10, 10)) + c := color.Gray{0x13} + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.SetGray(4, 5, c) + } +} + +func BenchmarkGray16At(b *testing.B) { + m := NewGray16(Rect(0, 0, 10, 10)) + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.Gray16At(4, 5) + } +} + +func BenchmarkGraySetGray16(b *testing.B) { + m := NewGray16(Rect(0, 0, 10, 10)) + c := color.Gray16{0x13} + b.ResetTimer() + + for i := 0; i < b.N; i++ { + m.SetGray16(4, 5, c) + } +} diff --git a/src/image/png/reader_test.go b/src/image/png/reader_test.go index 66bcfcb437..33dcd3debc 100644 --- a/src/image/png/reader_test.go +++ b/src/image/png/reader_test.go @@ -364,10 +364,6 @@ func TestReader(t *testing.T) { } defer sf.Close() sb := bufio.NewScanner(sf) - if err != nil { - t.Error(fn, err) - continue - } // Compare the two, in SNG format, line by line. for { diff --git a/src/image/png/writer.go b/src/image/png/writer.go index 49f1ad2e7f..c03335120e 100644 --- a/src/image/png/writer.go +++ b/src/image/png/writer.go @@ -7,6 +7,7 @@ package png import ( "bufio" "compress/zlib" + "encoding/binary" "hash/crc32" "image" "image/color" @@ -62,14 +63,6 @@ const ( // compression level, although that is not implemented yet. ) -// Big-endian. -func writeUint32(b []uint8, u uint32) { - b[0] = uint8(u >> 24) - b[1] = uint8(u >> 16) - b[2] = uint8(u >> 8) - b[3] = uint8(u >> 0) -} - type opaquer interface { Opaque() bool } @@ -108,7 +101,7 @@ func (e *encoder) writeChunk(b []byte, name string) { e.err = UnsupportedError(name + " chunk is too large: " + strconv.Itoa(len(b))) return } - writeUint32(e.header[:4], n) + binary.BigEndian.PutUint32(e.header[:4], n) e.header[4] = name[0] e.header[5] = name[1] e.header[6] = name[2] @@ -116,7 +109,7 @@ func (e *encoder) writeChunk(b []byte, name string) { crc := crc32.NewIEEE() crc.Write(e.header[4:8]) crc.Write(b) - writeUint32(e.footer[:4], crc.Sum32()) + binary.BigEndian.PutUint32(e.footer[:4], crc.Sum32()) _, e.err = e.w.Write(e.header[:8]) if e.err != nil { @@ -131,8 +124,8 @@ func (e *encoder) writeChunk(b []byte, name string) { func (e *encoder) writeIHDR() { b := e.m.Bounds() - writeUint32(e.tmp[0:4], uint32(b.Dx())) - writeUint32(e.tmp[4:8], uint32(b.Dy())) + binary.BigEndian.PutUint32(e.tmp[0:4], uint32(b.Dx())) + binary.BigEndian.PutUint32(e.tmp[4:8], uint32(b.Dy())) // Set bit depth and color type. switch e.cb { case cbG8: @@ -144,6 +137,15 @@ func (e *encoder) writeIHDR() { case cbP8: e.tmp[8] = 8 e.tmp[9] = ctPaletted + case cbP4: + e.tmp[8] = 4 + e.tmp[9] = ctPaletted + case cbP2: + e.tmp[8] = 2 + e.tmp[9] = ctPaletted + case cbP1: + e.tmp[8] = 1 + e.tmp[9] = ctPaletted case cbTCA8: e.tmp[8] = 8 e.tmp[9] = ctTrueColorAlpha @@ -312,31 +314,38 @@ func (e *encoder) writeImage(w io.Writer, m image.Image, cb int, level int) erro } defer e.zw.Close() - bpp := 0 // Bytes per pixel. + bitsPerPixel := 0 switch cb { case cbG8: - bpp = 1 + bitsPerPixel = 8 case cbTC8: - bpp = 3 + bitsPerPixel = 24 case cbP8: - bpp = 1 + bitsPerPixel = 8 + case cbP4: + bitsPerPixel = 4 + case cbP2: + bitsPerPixel = 2 + case cbP1: + bitsPerPixel = 1 case cbTCA8: - bpp = 4 + bitsPerPixel = 32 case cbTC16: - bpp = 6 + bitsPerPixel = 48 case cbTCA16: - bpp = 8 + bitsPerPixel = 64 case cbG16: - bpp = 2 + bitsPerPixel = 16 } + // cr[*] and pr are the bytes for the current and previous row. // cr[0] is unfiltered (or equivalently, filtered with the ftNone filter). // cr[ft], for non-zero filter types ft, are buffers for transforming cr[0] under the // other PNG filter types. These buffers are allocated once and re-used for each row. // The +1 is for the per-row filter type, which is at cr[*][0]. b := m.Bounds() - sz := 1 + bpp*b.Dx() + sz := 1 + (bitsPerPixel*b.Dx()+7)/8 for i := range e.cr { if cap(e.cr[i]) < sz { e.cr[i] = make([]uint8, sz) @@ -412,6 +421,30 @@ func (e *encoder) writeImage(w io.Writer, m image.Image, cb int, level int) erro i += 1 } } + + case cbP4, cbP2, cbP1: + pi := m.(image.PalettedImage) + + var a uint8 + var c int + for x := b.Min.X; x < b.Max.X; x++ { + a = a<<uint(bitsPerPixel) | pi.ColorIndexAt(x, y) + c++ + if c == 8/bitsPerPixel { + cr[0][i] = a + i += 1 + a = 0 + c = 0 + } + } + if c != 0 { + for c != 8/bitsPerPixel { + a = a << uint(bitsPerPixel) + c++ + } + cr[0][i] = a + } + case cbTCA8: if nrgba != nil { offset := (y - b.Min.Y) * nrgba.Stride @@ -467,7 +500,10 @@ func (e *encoder) writeImage(w io.Writer, m image.Image, cb int, level int) erro // "filters are rarely useful on palette images" and will result // in larger files (see http://www.libpng.org/pub/png/book/chapter09.html). f := ftNone - if level != zlib.NoCompression && cb != cbP8 { + if level != zlib.NoCompression && cb != cbP8 && cb != cbP4 && cb != cbP2 && cb != cbP1 { + // Since we skip paletted images we don't have to worry about + // bitsPerPixel not being a multiple of 8 + bpp := bitsPerPixel / 8 f = filter(&cr, pr, bpp) } @@ -558,7 +594,15 @@ func (enc *Encoder) Encode(w io.Writer, m image.Image) error { pal, _ = m.ColorModel().(color.Palette) } if pal != nil { - e.cb = cbP8 + if len(pal) <= 2 { + e.cb = cbP1 + } else if len(pal) <= 4 { + e.cb = cbP2 + } else if len(pal) <= 16 { + e.cb = cbP4 + } else { + e.cb = cbP8 + } } else { switch m.ColorModel() { case color.GrayModel: diff --git a/src/image/png/writer_test.go b/src/image/png/writer_test.go index 1107ea0e7f..5d131ff823 100644 --- a/src/image/png/writer_test.go +++ b/src/image/png/writer_test.go @@ -6,9 +6,12 @@ package png import ( "bytes" + "compress/zlib" + "encoding/binary" "fmt" "image" "image/color" + "io" "io/ioutil" "testing" ) @@ -61,12 +64,12 @@ func TestWriter(t *testing.T) { m1, err := readPNG(qfn) if err != nil { t.Error(fn, err) - return + continue } m2, err := encodeDecode(m1) if err != nil { t.Error(fn, err) - return + continue } // Compare the two. err = diff(m0, m2) @@ -77,6 +80,111 @@ func TestWriter(t *testing.T) { } } +func TestWriterPaletted(t *testing.T) { + const width, height = 32, 16 + + testCases := []struct { + plen int + bitdepth uint8 + datalen int + }{ + + { + plen: 256, + bitdepth: 8, + datalen: (1 + width) * height, + }, + + { + plen: 128, + bitdepth: 8, + datalen: (1 + width) * height, + }, + + { + plen: 16, + bitdepth: 4, + datalen: (1 + width/2) * height, + }, + + { + plen: 4, + bitdepth: 2, + datalen: (1 + width/4) * height, + }, + + { + plen: 2, + bitdepth: 1, + datalen: (1 + width/8) * height, + }, + } + + for _, tc := range testCases { + t.Run(fmt.Sprintf("plen-%d", tc.plen), func(t *testing.T) { + // Create a paletted image with the correct palette length + palette := make(color.Palette, tc.plen) + for i := range palette { + palette[i] = color.NRGBA{ + R: uint8(i), + G: uint8(i), + B: uint8(i), + A: 255, + } + } + m0 := image.NewPaletted(image.Rect(0, 0, width, height), palette) + + i := 0 + for y := 0; y < height; y++ { + for x := 0; x < width; x++ { + m0.SetColorIndex(x, y, uint8(i%tc.plen)) + i++ + } + } + + // Encode the image + var b bytes.Buffer + if err := Encode(&b, m0); err != nil { + t.Error(err) + return + } + const chunkFieldsLength = 12 // 4 bytes for length, name and crc + data := b.Bytes() + i = len(pngHeader) + + for i < len(data)-chunkFieldsLength { + length := binary.BigEndian.Uint32(data[i : i+4]) + name := string(data[i+4 : i+8]) + + switch name { + case "IHDR": + bitdepth := data[i+8+8] + if bitdepth != tc.bitdepth { + t.Errorf("got bitdepth %d, want %d", bitdepth, tc.bitdepth) + } + case "IDAT": + // Uncompress the image data + r, err := zlib.NewReader(bytes.NewReader(data[i+8 : i+8+int(length)])) + if err != nil { + t.Error(err) + return + } + n, err := io.Copy(ioutil.Discard, r) + if err != nil { + t.Errorf("got error while reading image data: %v", err) + } + if n != int64(tc.datalen) { + t.Errorf("got uncompressed data length %d, want %d", n, tc.datalen) + } + } + + i += chunkFieldsLength + int(length) + } + }) + + } +} + func TestWriterLevels(t *testing.T) { m := image.NewNRGBA(image.Rect(0, 0, 100, 100)) diff --git a/src/internal/bytealg/compare_amd64.s b/src/internal/bytealg/compare_amd64.s index 05bef4aad9..25effbc56f 100644 --- a/src/internal/bytealg/compare_amd64.s +++ b/src/internal/bytealg/compare_amd64.s @@ -63,7 +63,7 @@ loop: ADDQ $16, DI SUBQ $16, R8 JMP loop - + diff64: ADDQ $48, SI ADDQ $48, DI diff --git a/src/internal/bytealg/compare_amd64p32.s b/src/internal/bytealg/compare_amd64p32.s index 85ba6fa9ac..4687fd8a04 100644 --- a/src/internal/bytealg/compare_amd64p32.s +++ b/src/internal/bytealg/compare_amd64p32.s @@ -62,7 +62,7 @@ loop: ADDQ $16, DI SUBQ $16, R8 JMP loop - + // AX = bit mask of differences diff16: BSFQ AX, BX // index of first byte that differs diff --git a/src/internal/bytealg/count_generic.go b/src/internal/bytealg/count_generic.go index a763b3bc61..e24b2b7fa0 100644 --- a/src/internal/bytealg/count_generic.go +++ b/src/internal/bytealg/count_generic.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build !amd64,!arm64 +// +build !amd64,!arm64,!ppc64le,!ppc64 package bytealg diff --git a/src/internal/bytealg/count_native.go b/src/internal/bytealg/count_native.go index a62c4cb5c0..e6a91b3c0e 100644 --- a/src/internal/bytealg/count_native.go +++ b/src/internal/bytealg/count_native.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build amd64 arm64 +// +build amd64 arm64 ppc64le ppc64 package bytealg diff --git a/src/internal/bytealg/count_ppc64x.s b/src/internal/bytealg/count_ppc64x.s new file mode 100644 index 0000000000..7abdce1954 --- /dev/null +++ b/src/internal/bytealg/count_ppc64x.s @@ -0,0 +1,97 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build ppc64le ppc64 + +#include "go_asm.h" +#include "textflag.h" + +TEXT ·Count(SB), NOSPLIT|NOFRAME, $0-40 + MOVD b_base+0(FP), R3 // R3 = byte array pointer + MOVD b_len+8(FP), R4 // R4 = length + MOVBZ c+24(FP), R5 // R5 = byte + MOVD $ret+32(FP), R14 // R14 = &ret + BR countbytebody<>(SB) + +TEXT ·CountString(SB), NOSPLIT|NOFRAME, $0-32 + MOVD s_base+0(FP), R3 // R3 = string + MOVD s_len+8(FP), R4 // R4 = length + MOVBZ c+16(FP), R5 // R5 = byte + MOVD $ret+24(FP), R14 // R14 = &ret + BR countbytebody<>(SB) + +// R3: addr of string +// R4: len of string +// R5: byte to count +// R14: addr for return value +// endianness shouldn't matter since we are just counting and order +// is irrelevant +TEXT countbytebody<>(SB), NOSPLIT|NOFRAME, $0-0 + DCBT (R3) // Prepare cache line. + MOVD R0, R18 // byte count + MOVD R3, R19 // Save base address for calculating the index later. + MOVD R4, R16 + + MOVD R5, R6 + RLDIMI $8, R6, $48, R6 + RLDIMI $16, R6, $32, R6 + RLDIMI $32, R6, $0, R6 // fill reg with the byte to count + + VSPLTISW $3, V4 // used for shift + MTVRD R6, V1 // move compare byte + VSPLTB $7, V1, V1 // replicate byte across V1 + + CMPU R4, $32 // Check if it's a small string (<32 bytes) + BLT tail // Jump to the small string case + XXLXOR VS37, VS37, VS37 // clear V5 (aka VS37) to use as accumulator + +cmploop: + LXVW4X (R3), VS32 // load bytes from string + + // when the bytes match, the corresonding byte contains all 1s + VCMPEQUB V1, V0, V2 // compare bytes + VPOPCNTD V2, V3 // each double word contains its count + VADDUDM V3, V5, V5 // accumulate bit count in each double word + ADD $16, R3, R3 // increment pointer + SUB $16, R16, R16 // remaining bytes + CMP R16, $16 // at least 16 remaining? + BGE cmploop + VSRD V5, V4, V5 // shift by 3 to convert bits to bytes + VSLDOI $8, V5, V5, V6 // get the double word values from vector + MFVSRD V5, R9 + MFVSRD V6, R10 + ADD R9, R10, R9 + ADD R9, R18, R18 + +tail: + CMP R16, $8 // 8 bytes left? + BLT small + + MOVD (R3), R12 // load 8 bytes + CMPB R12, R6, R17 // compare bytes + POPCNTD R17, R15 // bit count + SRD $3, R15, R15 // byte count + ADD R15, R18, R18 // add to byte count + +next1: + ADD $8, R3, R3 + SUB $8, R16, R16 // remaining bytes + BR tail + +small: + CMP $0, R16 // any remaining + BEQ done + MOVBZ (R3), R12 // check each remaining byte + CMP R12, R5 + BNE next2 + ADD $1, R18 + +next2: + SUB $1, R16 + ADD $1, R3 // inc address + BR small + +done: + MOVD R18, (R14) // return count + RET diff --git a/src/internal/bytealg/equal_amd64.s b/src/internal/bytealg/equal_amd64.s index 5263d3040d..b695d9cf42 100644 --- a/src/internal/bytealg/equal_amd64.s +++ b/src/internal/bytealg/equal_amd64.s @@ -79,7 +79,7 @@ TEXT memeqbody<>(SB),NOSPLIT,$0-0 JB bigloop CMPB internal∕cpu·X86+const_offsetX86HasAVX2(SB), $1 JE hugeloop_avx2 - + // 64 bytes at a time using xmm registers hugeloop: CMPQ BX, $64 diff --git a/src/internal/bytealg/equal_amd64p32.s b/src/internal/bytealg/equal_amd64p32.s index c841f98b2f..9be4274c11 100644 --- a/src/internal/bytealg/equal_amd64p32.s +++ b/src/internal/bytealg/equal_amd64p32.s @@ -80,7 +80,7 @@ TEXT memeqbody<>(SB),NOSPLIT,$0-0 CMPQ BX, $8 JB small - + // 64 bytes at a time using xmm registers hugeloop: CMPQ BX, $64 diff --git a/src/internal/bytealg/equal_arm.s b/src/internal/bytealg/equal_arm.s index 6b0d7deed9..e8a92b3cf2 100644 --- a/src/internal/bytealg/equal_arm.s +++ b/src/internal/bytealg/equal_arm.s @@ -9,7 +9,7 @@ TEXT ·Equal(SB),NOSPLIT,$0-25 MOVW a_len+4(FP), R1 MOVW b_len+16(FP), R3 - + CMP R1, R3 // unequal lengths are not equal B.NE notequal diff --git a/src/internal/bytealg/equal_arm64.s b/src/internal/bytealg/equal_arm64.s index 30abd980c5..dd4840dae1 100644 --- a/src/internal/bytealg/equal_arm64.s +++ b/src/internal/bytealg/equal_arm64.s @@ -67,6 +67,7 @@ TEXT runtime·memequal_varlen(SB),NOSPLIT,$40-17 CMP R3, R4 BEQ eq MOVD 8(R26), R5 // compiler stores size at offset 8 in the closure + CBZ R5, eq MOVD R3, 8(RSP) MOVD R4, 16(RSP) MOVD R5, 24(RSP) @@ -119,30 +120,41 @@ chunk16: CBZ R3, tail ADD R3, R0, R6 // end of chunks chunk16_loop: - VLD1.P (R0), [V0.D2] - VLD1.P (R2), [V1.D2] - VCMEQ V0.D2, V1.D2, V2.D2 + LDP.P 16(R0), (R4, R5) + LDP.P 16(R2), (R7, R9) + EOR R4, R7 + CBNZ R7, not_equal + EOR R5, R9 + CBNZ R9, not_equal CMP R0, R6 - VMOV V2.D[0], R4 - VMOV V2.D[1], R5 - CBZ R4, not_equal - CBZ R5, not_equal BNE chunk16_loop AND $0xf, R1, R1 CBZ R1, equal tail: // special compare of tail with length < 16 TBZ $3, R1, lt_8 - MOVD.P 8(R0), R4 - MOVD.P 8(R2), R5 - CMP R4, R5 - BNE not_equal + MOVD (R0), R4 + MOVD (R2), R5 + EOR R4, R5 + CBNZ R5, not_equal + SUB $8, R1, R6 // offset of the last 8 bytes + MOVD (R0)(R6), R4 + MOVD (R2)(R6), R5 + EOR R4, R5 + CBNZ R5, not_equal + B equal lt_8: TBZ $2, R1, lt_4 - MOVWU.P 4(R0), R4 - MOVWU.P 4(R2), R5 - CMP R4, R5 - BNE not_equal + MOVWU (R0), R4 + MOVWU (R2), R5 + EOR R4, R5 + CBNZ R5, not_equal + SUB $4, R1, R6 // offset of the last 4 bytes + MOVWU (R0)(R6), R4 + MOVWU (R2)(R6), R5 + EOR R4, R5 + CBNZ R5, not_equal + B equal lt_4: TBZ $1, R1, lt_2 MOVHU.P 2(R0), R4 @@ -150,7 +162,7 @@ lt_4: CMP R4, R5 BNE not_equal lt_2: - TBZ $0, R1, equal + TBZ $0, R1, equal one: MOVBU (R0), R4 MOVBU (R2), R5 diff --git a/src/internal/bytealg/indexbyte_ppc64x.s b/src/internal/bytealg/indexbyte_ppc64x.s index ccf897d99c..61b33bc9cb 100644 --- a/src/internal/bytealg/indexbyte_ppc64x.s +++ b/src/internal/bytealg/indexbyte_ppc64x.s @@ -38,14 +38,14 @@ TEXT strings·IndexByte(SB),NOSPLIT|NOFRAME,$0-32 BR indexbytebody<>(SB) TEXT indexbytebody<>(SB),NOSPLIT|NOFRAME,$0-0 - DCBT (R3) // Prepare cache line. MOVD R3,R17 // Save base address for calculating the index later. RLDICR $0,R3,$60,R8 // Align address to doubleword boundary in R8. RLDIMI $8,R5,$48,R5 // Replicating the byte across the register. ADD R4,R3,R7 // Last acceptable address in R7. + DCBT (R8) // Prepare cache line. RLDIMI $16,R5,$32,R5 - CMPU R4,$32 // Check if it's a small string (<32 bytes). Those will be processed differently. + CMPU R4,$32 // Check if it's a small string (≤32 bytes). Those will be processed differently. MOVD $-1,R9 WORD $0x54661EB8 // Calculate padding in R6 (rlwinm r6,r3,3,26,28). RLDIMI $32,R5,$0,R5 @@ -56,7 +56,7 @@ TEXT indexbytebody<>(SB),NOSPLIT|NOFRAME,$0-0 #else SRD R6,R9,R9 // Same for Big Endian #endif - BLE small_string // Jump to the small string case if it's <32 bytes. + BLE small_string // Jump to the small string case if it's ≤32 bytes. // If we are 64-byte aligned, branch to qw_align just to get the auxiliary values // in V0, V1 and V10, then branch to the preloop. @@ -97,7 +97,7 @@ qw_align: LVSL (R0+R0),V11 VSLB V11,V10,V10 VSPLTB $7,V1,V1 // Replicate byte across V1 - CMPU R4, $64 // If len <= 64, don't use the vectorized loop + CMPU R4, $64 // If len ≤ 64, don't use the vectorized loop BLE tail // We will load 4 quardwords per iteration in the loop, so check for @@ -131,7 +131,7 @@ qw_align: // 64-byte aligned. Prepare for the main loop. preloop: CMPU R4,$64 - BLE tail // If len <= 64, don't use the vectorized loop + BLE tail // If len ≤ 64, don't use the vectorized loop // We are now aligned to a 64-byte boundary. We will load 4 quadwords // per loop iteration. The last doubleword is in R10, so our loop counter @@ -140,30 +140,34 @@ preloop: SRD $6,R6,R9 // Loop counter in R9 MOVD R9,CTR + ADD $-64,R8,R8 // Adjust index for loop entry MOVD $16,R11 // Load offsets for the vector loads MOVD $32,R9 MOVD $48,R7 // Main loop we will load 64 bytes per iteration loop: + ADD $64,R8,R8 // Fuse addi+lvx for performance LVX (R8+R0),V2 // Load 4 16-byte vectors - LVX (R11+R8),V3 - LVX (R9+R8),V4 - LVX (R7+R8),V5 + LVX (R8+R11),V3 VCMPEQUB V1,V2,V6 // Look for byte in each vector VCMPEQUB V1,V3,V7 + + LVX (R8+R9),V4 + LVX (R8+R7),V5 VCMPEQUB V1,V4,V8 VCMPEQUB V1,V5,V9 + VOR V6,V7,V11 // Compress the result in a single vector VOR V8,V9,V12 - VOR V11,V12,V11 - VCMPEQUBCC V0,V11,V11 // Check for byte + VOR V11,V12,V13 + VCMPEQUBCC V0,V13,V14 // Check for byte BGE CR6,found - ADD $64,R8,R8 BC 16,0,loop // bdnz loop - // Handle the tailing bytes or R4 <= 64 + // Handle the tailing bytes or R4 ≤ 64 RLDICL $0,R6,$58,R4 + ADD $64,R8,R8 tail: CMPU R4,$0 BEQ notfound diff --git a/src/internal/goroot/gc.go b/src/internal/goroot/gc.go new file mode 100644 index 0000000000..b9da9a5301 --- /dev/null +++ b/src/internal/goroot/gc.go @@ -0,0 +1,140 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build gc + +package goroot + +import ( + "os" + "os/exec" + "path/filepath" + "strings" + "sync" +) + +// IsStandardPackage returns whether path is a standard package, +// given goroot and compiler. +func IsStandardPackage(goroot, compiler, path string) bool { + switch compiler { + case "gc": + dir := filepath.Join(goroot, "src", path) + _, err := os.Stat(dir) + return err == nil + case "gccgo": + return gccgoSearch.isStandard(path) + default: + panic("unknown compiler " + compiler) + } +} + +// gccgoSearch holds the gccgo search directories. +type gccgoDirs struct { + once sync.Once + dirs []string +} + +// gccgoSearch is used to check whether a gccgo package exists in the +// standard library. +var gccgoSearch gccgoDirs + +// init finds the gccgo search directories. If this fails it leaves dirs == nil. +func (gd *gccgoDirs) init() { + gccgo := os.Getenv("GCCGO") + if gccgo == "" { + gccgo = "gccgo" + } + bin, err := exec.LookPath(gccgo) + if err != nil { + return + } + + allDirs, err := exec.Command(bin, "-print-search-dirs").Output() + if err != nil { + return + } + versionB, err := exec.Command(bin, "-dumpversion").Output() + if err != nil { + return + } + version := strings.TrimSpace(string(versionB)) + machineB, err := exec.Command(bin, "-dumpmachine").Output() + if err != nil { + return + } + machine := strings.TrimSpace(string(machineB)) + + dirsEntries := strings.Split(string(allDirs), "\n") + const prefix = "libraries: =" + var dirs []string + for _, dirEntry := range dirsEntries { + if strings.HasPrefix(dirEntry, prefix) { + dirs = filepath.SplitList(strings.TrimPrefix(dirEntry, prefix)) + break + } + } + if len(dirs) == 0 { + return + } + + var lastDirs []string + for _, dir := range dirs { + goDir := filepath.Join(dir, "go", version) + if fi, err := os.Stat(goDir); err == nil && fi.IsDir() { + gd.dirs = append(gd.dirs, goDir) + goDir = filepath.Join(goDir, machine) + if fi, err = os.Stat(goDir); err == nil && fi.IsDir() { + gd.dirs = append(gd.dirs, goDir) + } + } + if fi, err := os.Stat(dir); err == nil && fi.IsDir() { + lastDirs = append(lastDirs, dir) + } + } + gd.dirs = append(gd.dirs, lastDirs...) +} + +// isStandard returns whether path is a standard library for gccgo. +func (gd *gccgoDirs) isStandard(path string) bool { + // Quick check: if the first path component has a '.', it's not + // in the standard library. This skips most GOPATH directories. + i := strings.Index(path, "/") + if i < 0 { + i = len(path) + } + if strings.Contains(path[:i], ".") { + return false + } + + if path == "unsafe" { + // Special case. + return true + } + + gd.once.Do(gd.init) + if gd.dirs == nil { + // We couldn't find the gccgo search directories. + // Best guess, since the first component did not contain + // '.', is that this is a standard library package. + return true + } + + for _, dir := range gd.dirs { + full := filepath.Join(dir, path) + pkgdir, pkg := filepath.Split(full) + for _, p := range [...]string{ + full, + full + ".gox", + pkgdir + "lib" + pkg + ".so", + pkgdir + "lib" + pkg + ".a", + full + ".o", + } { + if fi, err := os.Stat(p); err == nil && !fi.IsDir() { + return true + } + } + } + + return false +} diff --git a/src/internal/goroot/gccgo.go b/src/internal/goroot/gccgo.go new file mode 100644 index 0000000000..098e77d893 --- /dev/null +++ b/src/internal/goroot/gccgo.go @@ -0,0 +1,27 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build gccgo + +package goroot + +import ( + "os" + "path/filepath" +) + +// IsStandardPackage returns whether path is a standard package, +// given goroot and compiler. +func IsStandardPackage(goroot, compiler, path string) bool { + switch compiler { + case "gc": + dir := filepath.Join(goroot, "src", path) + _, err := os.Stat(dir) + return err == nil + case "gccgo": + return stdpkg[path] + default: + panic("unknown compiler " + compiler) + } +} diff --git a/src/internal/poll/export_posix_test.go b/src/internal/poll/export_posix_test.go index 73b2c11e1e..6b9bb8b7d0 100644 --- a/src/internal/poll/export_posix_test.go +++ b/src/internal/poll/export_posix_test.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows +// +build aix darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows // Export guts for testing on posix. // Since testing imports os and os imports internal/poll, diff --git a/src/internal/poll/fd_poll_runtime.go b/src/internal/poll/fd_poll_runtime.go index 87a01a8b69..b91cbe40e4 100644 --- a/src/internal/poll/fd_poll_runtime.go +++ b/src/internal/poll/fd_poll_runtime.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux netbsd openbsd windows solaris +// +build aix darwin dragonfly freebsd linux netbsd openbsd windows solaris package poll diff --git a/src/internal/poll/fd_posix.go b/src/internal/poll/fd_posix.go index f899a74876..b43ad51799 100644 --- a/src/internal/poll/fd_posix.go +++ b/src/internal/poll/fd_posix.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris windows +// +build aix darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris windows package poll diff --git a/src/internal/poll/fd_posix_test.go b/src/internal/poll/fd_posix_test.go index cbe015edbd..246d4989e1 100644 --- a/src/internal/poll/fd_posix_test.go +++ b/src/internal/poll/fd_posix_test.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows +// +build aix darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows package poll_test diff --git a/src/internal/poll/fd_unix.go b/src/internal/poll/fd_unix.go index b311049ad7..21966ad466 100644 --- a/src/internal/poll/fd_unix.go +++ b/src/internal/poll/fd_unix.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris +// +build aix darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris package poll diff --git a/src/internal/poll/fd_windows.go b/src/internal/poll/fd_windows.go index b08cec2625..19d9a12dad 100644 --- a/src/internal/poll/fd_windows.go +++ b/src/internal/poll/fd_windows.go @@ -116,11 +116,17 @@ func (o *operation) InitBufs(buf *[][]byte) { o.bufs = o.bufs[:0] } for _, b := range *buf { - var p *byte + if len(b) == 0 { + o.bufs = append(o.bufs, syscall.WSABuf{}) + continue + } + for len(b) > maxRW { + o.bufs = append(o.bufs, syscall.WSABuf{Len: maxRW, Buf: &b[0]}) + b = b[maxRW:] + } if len(b) > 0 { - p = &b[0] + o.bufs = append(o.bufs, syscall.WSABuf{Len: uint32(len(b)), Buf: &b[0]}) } - o.bufs = append(o.bufs, syscall.WSABuf{Len: uint32(len(b)), Buf: p}) } } @@ -461,6 +467,11 @@ func (fd *FD) Shutdown(how int) error { return syscall.Shutdown(fd.Sysfd, how) } +// Windows ReadFile and WSARecv use DWORD (uint32) parameter to pass buffer length. +// This prevents us reading blocks larger than 4GB. +// See golang.org/issue/26923. +const maxRW = 1 << 30 // 1GB is large enough and keeps subsequent reads aligned + // Read implements io.Reader. func (fd *FD) Read(buf []byte) (int, error) { if err := fd.readLock(); err != nil { @@ -468,6 +479,10 @@ func (fd *FD) Read(buf []byte) (int, error) { } defer fd.readUnlock() + if len(buf) > maxRW { + buf = buf[:maxRW] + } + var n int var err error if fd.isFile || fd.isDir || fd.isConsole { @@ -581,6 +596,10 @@ func (fd *FD) Pread(b []byte, off int64) (int, error) { } defer fd.decref() + if len(b) > maxRW { + b = b[:maxRW] + } + fd.l.Lock() defer fd.l.Unlock() curoffset, e := syscall.Seek(fd.Sysfd, 0, io.SeekCurrent) @@ -611,6 +630,9 @@ func (fd *FD) ReadFrom(buf []byte) (int, syscall.Sockaddr, error) { if len(buf) == 0 { return 0, nil, nil } + if len(buf) > maxRW { + buf = buf[:maxRW] + } if err := fd.readLock(); err != nil { return 0, nil, err } @@ -639,30 +661,42 @@ func (fd *FD) Write(buf []byte) (int, error) { } defer fd.writeUnlock() - var n int - var err error - if fd.isFile || fd.isDir || fd.isConsole { - fd.l.Lock() - defer fd.l.Unlock() - if fd.isConsole { - n, err = fd.writeConsole(buf) + ntotal := 0 + for len(buf) > 0 { + b := buf + if len(b) > maxRW { + b = b[:maxRW] + } + var n int + var err error + if fd.isFile || fd.isDir || fd.isConsole { + fd.l.Lock() + defer fd.l.Unlock() + if fd.isConsole { + n, err = fd.writeConsole(b) + } else { + n, err = syscall.Write(fd.Sysfd, b) + } + if err != nil { + n = 0 + } } else { - n, err = syscall.Write(fd.Sysfd, buf) + if race.Enabled { + race.ReleaseMerge(unsafe.Pointer(&ioSync)) + } + o := &fd.wop + o.InitBuf(b) + n, err = wsrv.ExecIO(o, func(o *operation) error { + return syscall.WSASend(o.fd.Sysfd, &o.buf, 1, &o.qty, 0, &o.o, nil) + }) } + ntotal += n if err != nil { - n = 0 - } - } else { - if race.Enabled { - race.ReleaseMerge(unsafe.Pointer(&ioSync)) + return ntotal, err } - o := &fd.wop - o.InitBuf(buf) - n, err = wsrv.ExecIO(o, func(o *operation) error { - return syscall.WSASend(o.fd.Sysfd, &o.buf, 1, &o.qty, 0, &o.o, nil) - }) + buf = buf[n:] } - return n, err + return ntotal, nil } // writeConsole writes len(b) bytes to the console File. @@ -709,7 +743,7 @@ func (fd *FD) writeConsole(b []byte) (int, error) { } // Pwrite emulates the Unix pwrite system call. -func (fd *FD) Pwrite(b []byte, off int64) (int, error) { +func (fd *FD) Pwrite(buf []byte, off int64) (int, error) { // Call incref, not writeLock, because since pwrite specifies the // offset it is independent from other writes. if err := fd.incref(); err != nil { @@ -724,16 +758,27 @@ func (fd *FD) Pwrite(b []byte, off int64) (int, error) { return 0, e } defer syscall.Seek(fd.Sysfd, curoffset, io.SeekStart) - o := syscall.Overlapped{ - OffsetHigh: uint32(off >> 32), - Offset: uint32(off), - } - var done uint32 - e = syscall.WriteFile(fd.Sysfd, b, &done, &o) - if e != nil { - return 0, e + + ntotal := 0 + for len(buf) > 0 { + b := buf + if len(b) > maxRW { + b = b[:maxRW] + } + var n uint32 + o := syscall.Overlapped{ + OffsetHigh: uint32(off >> 32), + Offset: uint32(off), + } + e = syscall.WriteFile(fd.Sysfd, b, &n, &o) + ntotal += int(n) + if e != nil { + return ntotal, e + } + buf = buf[n:] + off += int64(n) } - return int(done), nil + return ntotal, nil } // Writev emulates the Unix writev system call. @@ -765,13 +810,37 @@ func (fd *FD) WriteTo(buf []byte, sa syscall.Sockaddr) (int, error) { return 0, err } defer fd.writeUnlock() - o := &fd.wop - o.InitBuf(buf) - o.sa = sa - n, err := wsrv.ExecIO(o, func(o *operation) error { - return syscall.WSASendto(o.fd.Sysfd, &o.buf, 1, &o.qty, 0, o.sa, &o.o, nil) - }) - return n, err + + if len(buf) == 0 { + // handle zero-byte payload + o := &fd.wop + o.InitBuf(buf) + o.sa = sa + n, err := wsrv.ExecIO(o, func(o *operation) error { + return syscall.WSASendto(o.fd.Sysfd, &o.buf, 1, &o.qty, 0, o.sa, &o.o, nil) + }) + return n, err + } + + ntotal := 0 + for len(buf) > 0 { + b := buf + if len(b) > maxRW { + b = b[:maxRW] + } + o := &fd.wop + o.InitBuf(b) + o.sa = sa + n, err := wsrv.ExecIO(o, func(o *operation) error { + return syscall.WSASendto(o.fd.Sysfd, &o.buf, 1, &o.qty, 0, o.sa, &o.o, nil) + }) + ntotal += int(n) + if err != nil { + return ntotal, err + } + buf = buf[n:] + } + return ntotal, nil } // Call ConnectEx. This doesn't need any locking, since it is only @@ -986,6 +1055,10 @@ func (fd *FD) ReadMsg(p []byte, oob []byte) (int, int, int, syscall.Sockaddr, er } defer fd.readUnlock() + if len(p) > maxRW { + p = p[:maxRW] + } + o := &fd.rop o.InitMsg(p, oob) o.rsa = new(syscall.RawSockaddrAny) @@ -1004,6 +1077,10 @@ func (fd *FD) ReadMsg(p []byte, oob []byte) (int, int, int, syscall.Sockaddr, er // WriteMsg wraps the WSASendMsg network call. func (fd *FD) WriteMsg(p []byte, oob []byte, sa syscall.Sockaddr) (int, int, error) { + if len(p) > maxRW { + return 0, 0, errors.New("packet is too large (only 1GB is allowed)") + } + if err := fd.writeLock(); err != nil { return 0, 0, err } diff --git a/src/internal/poll/hook_unix.go b/src/internal/poll/hook_unix.go index c2ad17eb1a..a7512b1255 100644 --- a/src/internal/poll/hook_unix.go +++ b/src/internal/poll/hook_unix.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris +// +build aix darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris package poll diff --git a/src/internal/poll/sockopt.go b/src/internal/poll/sockopt.go index f86ce707a1..bb5ea02c0a 100644 --- a/src/internal/poll/sockopt.go +++ b/src/internal/poll/sockopt.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux netbsd openbsd solaris windows +// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris windows package poll diff --git a/src/internal/poll/sockopt_unix.go b/src/internal/poll/sockopt_unix.go index b33644db76..bd942c2934 100644 --- a/src/internal/poll/sockopt_unix.go +++ b/src/internal/poll/sockopt_unix.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux netbsd openbsd solaris +// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris package poll diff --git a/src/internal/poll/sockoptip.go b/src/internal/poll/sockoptip.go index 1ee490c257..c55a1e3c5b 100644 --- a/src/internal/poll/sockoptip.go +++ b/src/internal/poll/sockoptip.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux netbsd openbsd solaris windows +// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris windows package poll diff --git a/src/internal/poll/splice_linux.go b/src/internal/poll/splice_linux.go index aa237e587a..4f97298417 100644 --- a/src/internal/poll/splice_linux.go +++ b/src/internal/poll/splice_linux.go @@ -32,8 +32,6 @@ func Splice(dst, src *FD, remain int64) (written int64, handled bool, sc string, return 0, false, sc, err } defer destroyTempPipe(prfd, pwfd) - // From here on, the operation should be considered handled, - // even if Splice doesn't transfer any data. var inPipe, n int for err == nil && remain > 0 { max := maxSpliceSize @@ -41,9 +39,18 @@ func Splice(dst, src *FD, remain int64) (written int64, handled bool, sc string, max = int(remain) } inPipe, err = spliceDrain(pwfd, src, max) + // The operation is considered handled if splice returns no + // error, or an error other than EINVAL. An EINVAL means the + // kernel does not support splice for the socket type of src. + // The failed syscall does not consume any data so it is safe + // to fall back to a generic copy. + // // spliceDrain should never return EAGAIN, so if err != nil, - // Splice cannot continue. If inPipe == 0 && err == nil, - // src is at EOF, and the transfer is complete. + // Splice cannot continue. + // + // If inPipe == 0 && err == nil, src is at EOF, and the + // transfer is complete. + handled = handled || (err != syscall.EINVAL) if err != nil || (inPipe == 0 && err == nil) { break } @@ -54,7 +61,7 @@ func Splice(dst, src *FD, remain int64) (written int64, handled bool, sc string, } } if err != nil { - return written, true, "splice", err + return written, handled, "splice", err } return written, true, "", nil } diff --git a/src/internal/poll/sys_cloexec.go b/src/internal/poll/sys_cloexec.go index 7bafa0d81a..64e46127d4 100644 --- a/src/internal/poll/sys_cloexec.go +++ b/src/internal/poll/sys_cloexec.go @@ -5,7 +5,7 @@ // This file implements sysSocket and accept for platforms that do not // provide a fast path for setting SetNonblock and CloseOnExec. -// +build darwin js,wasm nacl solaris +// +build aix darwin js,wasm nacl solaris package poll diff --git a/src/internal/syscall/unix/nonblocking.go b/src/internal/syscall/unix/nonblocking.go index 1db3394432..233b6689d1 100644 --- a/src/internal/syscall/unix/nonblocking.go +++ b/src/internal/syscall/unix/nonblocking.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux netbsd openbsd solaris +// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris package unix diff --git a/src/io/io.go b/src/io/io.go index 72b75813a5..2010770e6a 100644 --- a/src/io/io.go +++ b/src/io/io.go @@ -278,16 +278,16 @@ type RuneScanner interface { UnreadRune() error } -// stringWriter is the interface that wraps the WriteString method. -type stringWriter interface { +// StringWriter is the interface that wraps the WriteString method. +type StringWriter interface { WriteString(s string) (n int, err error) } // WriteString writes the contents of the string s to w, which accepts a slice of bytes. -// If w implements a WriteString method, it is invoked directly. +// If w implements StringWriter, its WriteString method is invoked directly. // Otherwise, w.Write is called exactly once. func WriteString(w Writer, s string) (n int, err error) { - if sw, ok := w.(stringWriter); ok { + if sw, ok := w.(StringWriter); ok { return sw.WriteString(s) } return w.Write([]byte(s)) diff --git a/src/io/multi.go b/src/io/multi.go index 65f99099ca..24ee71e4ca 100644 --- a/src/io/multi.go +++ b/src/io/multi.go @@ -69,12 +69,12 @@ func (t *multiWriter) Write(p []byte) (n int, err error) { return len(p), nil } -var _ stringWriter = (*multiWriter)(nil) +var _ StringWriter = (*multiWriter)(nil) func (t *multiWriter) WriteString(s string) (n int, err error) { var p []byte // lazily initialized if/when needed for _, w := range t.writers { - if sw, ok := w.(stringWriter); ok { + if sw, ok := w.(StringWriter); ok { n, err = sw.WriteString(s) } else { if p == nil { diff --git a/src/math/all_test.go b/src/math/all_test.go index 00f2058ea6..6a6d8bf6d0 100644 --- a/src/math/all_test.go +++ b/src/math/all_test.go @@ -3635,3 +3635,41 @@ func BenchmarkYn(b *testing.B) { } GlobalF = x } + +func BenchmarkFloat64bits(b *testing.B) { + y := uint64(0) + for i := 0; i < b.N; i++ { + y = Float64bits(roundNeg) + } + GlobalI = int(y) +} + +var roundUint64 = uint64(5) + +func BenchmarkFloat64frombits(b *testing.B) { + x := 0.0 + for i := 0; i < b.N; i++ { + x = Float64frombits(roundUint64) + } + GlobalF = x +} + +var roundFloat32 = float32(-2.5) + +func BenchmarkFloat32bits(b *testing.B) { + y := uint32(0) + for i := 0; i < b.N; i++ { + y = Float32bits(roundFloat32) + } + GlobalI = int(y) +} + +var roundUint32 = uint32(5) + +func BenchmarkFloat32frombits(b *testing.B) { + x := float32(0.0) + for i := 0; i < b.N; i++ { + x = Float32frombits(roundUint32) + } + GlobalF = float64(x) +} diff --git a/src/math/big/arith_386.s b/src/math/big/arith_386.s index 6c080f074a..864fbc554e 100644 --- a/src/math/big/arith_386.s +++ b/src/math/big/arith_386.s @@ -183,7 +183,7 @@ L9: MOVL AX, DX // w = w1 SHRL CX, DX:AX // w>>s | w1<<ŝ MOVL DX, (DI)(BX*4) // z[i] = w>>s | w1<<ŝ ADDL $1, BX // i++ - + E9: CMPL BX, BP JL L9 // i < n-1 diff --git a/src/math/big/arith_amd64.s b/src/math/big/arith_amd64.s index 1b950a4a25..e9c8887523 100644 --- a/src/math/big/arith_amd64.s +++ b/src/math/big/arith_amd64.s @@ -324,10 +324,10 @@ TEXT ·mulAddVWW(SB),NOSPLIT,$0 MOVQ r+56(FP), CX // c = r MOVQ z_len+8(FP), R11 MOVQ $0, BX // i = 0 - + CMPQ R11, $4 JL E5 - + U5: // i+4 <= n // regular loop body unrolled 4x MOVQ (0*8)(R8)(BX*8), AX @@ -355,7 +355,7 @@ U5: // i+4 <= n MOVQ AX, (3*8)(R10)(BX*8) MOVQ DX, CX ADDQ $4, BX // i += 4 - + LEAQ 4(BX), DX CMPQ DX, R11 JLE U5 diff --git a/src/math/big/arith_arm.s b/src/math/big/arith_arm.s index ba65fd2b1f..33aa36f709 100644 --- a/src/math/big/arith_arm.s +++ b/src/math/big/arith_arm.s @@ -123,7 +123,7 @@ TEXT ·shlVU(SB),NOSPLIT,$0 MOVW z_len+4(FP), R5 TEQ $0, R5 BEQ X7 - + MOVW z+0(FP), R1 MOVW x+12(FP), R2 ADD R5<<2, R2, R2 @@ -135,7 +135,7 @@ TEXT ·shlVU(SB),NOSPLIT,$0 MOVW $32, R4 SUB R3, R4 MOVW $0, R7 - + MOVW.W -4(R2), R6 MOVW R6<<R3, R7 MOVW R6>>R4, R6 diff --git a/src/math/big/arith_s390x.s b/src/math/big/arith_s390x.s index 4520d161d7..9156d9debe 100644 --- a/src/math/big/arith_s390x.s +++ b/src/math/big/arith_s390x.s @@ -54,7 +54,7 @@ TEXT ·divWW(SB),NOSPLIT,$0 TEXT ·addVV(SB),NOSPLIT,$0 MOVD addvectorfacility+0x00(SB),R1 BR (R1) - + TEXT ·addVV_check(SB),NOSPLIT, $0 MOVB ·hasVX(SB), R1 CMPBEQ R1, $1, vectorimpl // vectorfacility = 1, vector supported @@ -89,7 +89,7 @@ TEXT ·addVV_vec(SB),NOSPLIT,$0 BLT v1 SUB $12, R3 // n -= 16 BLT A1 // if n < 0 goto A1 - + MOVD R8, R5 MOVD R9, R6 MOVD R2, R7 @@ -291,7 +291,7 @@ E1n: NEG R4, R4 TEXT ·subVV(SB),NOSPLIT,$0 MOVD subvectorfacility+0x00(SB),R1 BR (R1) - + TEXT ·subVV_check(SB),NOSPLIT,$0 MOVB ·hasVX(SB), R1 CMPBEQ R1, $1, vectorimpl // vectorfacility = 1, vector supported @@ -321,7 +321,7 @@ TEXT ·subVV_vec(SB),NOSPLIT,$0 MOVD $0, R4 // c = 0 MOVD $0, R0 // make sure it's zero MOVD $0, R10 // i = 0 - + // s/JL/JMP/ below to disable the unrolled loop SUB $4, R3 // n -= 4 BLT v1 // if n < 0 goto v1 @@ -413,7 +413,7 @@ UU1: VLM 0(R5), V1, V4 // 64-bytes into V1..V8 A1: ADD $12, R3 // n += 16 BLT v1 // if n < 0 goto v1 - + U1: // n >= 0 // regular loop body unrolled 4x MOVD 0(R8)(R10*1), R5 @@ -532,7 +532,7 @@ E1: NEG R4, R4 TEXT ·addVW(SB),NOSPLIT,$0 MOVD addwvectorfacility+0x00(SB),R1 BR (R1) - + TEXT ·addVW_check(SB),NOSPLIT,$0 MOVB ·hasVX(SB), R1 CMPBEQ R1, $1, vectorimpl // vectorfacility = 1, vector supported @@ -742,7 +742,7 @@ E4: MOVD R4, c+56(FP) // return c TEXT ·subVW(SB),NOSPLIT,$0 MOVD subwvectorfacility+0x00(SB),R1 BR (R1) - + TEXT ·subVW_check(SB),NOSPLIT,$0 MOVB ·hasVX(SB), R1 CMPBEQ R1, $1, vectorimpl // vectorfacility = 1, vector supported diff --git a/src/math/bits/bits.go b/src/math/bits/bits.go index 989baacc13..58cf52d2a7 100644 --- a/src/math/bits/bits.go +++ b/src/math/bits/bits.go @@ -328,3 +328,197 @@ func Len64(x uint64) (n int) { } return n + int(len8tab[x]) } + +// --- Add with carry --- + +// Add returns the sum with carry of x, y and carry: sum = x + y + carry. +// The carry input must be 0 or 1; otherwise the behavior is undefined. +// The carryOut output is guaranteed to be 0 or 1. +func Add(x, y, carry uint) (sum, carryOut uint) { + yc := y + carry + sum = x + yc + if sum < x || yc < y { + carryOut = 1 + } + return +} + +// Add32 returns the sum with carry of x, y and carry: sum = x + y + carry. +// The carry input must be 0 or 1; otherwise the behavior is undefined. +// The carryOut output is guaranteed to be 0 or 1. +func Add32(x, y, carry uint32) (sum, carryOut uint32) { + yc := y + carry + sum = x + yc + if sum < x || yc < y { + carryOut = 1 + } + return +} + +// Add64 returns the sum with carry of x, y and carry: sum = x + y + carry. +// The carry input must be 0 or 1; otherwise the behavior is undefined. +// The carryOut output is guaranteed to be 0 or 1. +func Add64(x, y, carry uint64) (sum, carryOut uint64) { + yc := y + carry + sum = x + yc + if sum < x || yc < y { + carryOut = 1 + } + return +} + +// --- Subtract with borrow --- + +// Sub returns the difference of x, y and borrow: diff = x - y - borrow. +// The borrow input must be 0 or 1; otherwise the behavior is undefined. +// The borrowOut output is guaranteed to be 0 or 1. +func Sub(x, y, borrow uint) (diff, borrowOut uint) { + yb := y + borrow + diff = x - yb + if diff > x || yb < y { + borrowOut = 1 + } + return +} + +// Sub32 returns the difference of x, y and borrow, diff = x - y - borrow. +// The borrow input must be 0 or 1; otherwise the behavior is undefined. +// The borrowOut output is guaranteed to be 0 or 1. +func Sub32(x, y, borrow uint32) (diff, borrowOut uint32) { + yb := y + borrow + diff = x - yb + if diff > x || yb < y { + borrowOut = 1 + } + return +} + +// Sub64 returns the difference of x, y and borrow: diff = x - y - borrow. +// The borrow input must be 0 or 1; otherwise the behavior is undefined. +// The borrowOut output is guaranteed to be 0 or 1. +func Sub64(x, y, borrow uint64) (diff, borrowOut uint64) { + yb := y + borrow + diff = x - yb + if diff > x || yb < y { + borrowOut = 1 + } + return +} + +// --- Full-width multiply --- + +// Mul returns the full-width product of x and y: (hi, lo) = x * y +// with the product bits' upper half returned in hi and the lower +// half returned in lo. +func Mul(x, y uint) (hi, lo uint) { + if UintSize == 32 { + h, l := Mul32(uint32(x), uint32(y)) + return uint(h), uint(l) + } + h, l := Mul64(uint64(x), uint64(y)) + return uint(h), uint(l) +} + +// Mul32 returns the 64-bit product of x and y: (hi, lo) = x * y +// with the product bits' upper half returned in hi and the lower +// half returned in lo. +func Mul32(x, y uint32) (hi, lo uint32) { + tmp := uint64(x) * uint64(y) + hi, lo = uint32(tmp>>32), uint32(tmp) + return +} + +// Mul64 returns the 128-bit product of x and y: (hi, lo) = x * y +// with the product bits' upper half returned in hi and the lower +// half returned in lo. +func Mul64(x, y uint64) (hi, lo uint64) { + const mask32 = 1<<32 - 1 + x0 := x & mask32 + x1 := x >> 32 + y0 := y & mask32 + y1 := y >> 32 + w0 := x0 * y0 + t := x1*y0 + w0>>32 + w1 := t & mask32 + w2 := t >> 32 + w1 += x0 * y1 + hi = x1*y1 + w2 + w1>>32 + lo = x * y + return +} + +// --- Full-width divide --- + +// Div returns the quotient and remainder of (hi, lo) divided by y: +// quo = (hi, lo)/y, rem = (hi, lo)%y with the dividend bits' upper +// half in parameter hi and the lower half in parameter lo. +// hi must be < y otherwise the behavior is undefined (the quotient +// won't fit into quo). +func Div(hi, lo, y uint) (quo, rem uint) { + if UintSize == 32 { + q, r := Div32(uint32(hi), uint32(lo), uint32(y)) + return uint(q), uint(r) + } + q, r := Div64(uint64(hi), uint64(lo), uint64(y)) + return uint(q), uint(r) +} + +// Div32 returns the quotient and remainder of (hi, lo) divided by y: +// quo = (hi, lo)/y, rem = (hi, lo)%y with the dividend bits' upper +// half in parameter hi and the lower half in parameter lo. +// hi must be < y otherwise the behavior is undefined (the quotient +// won't fit into quo). +func Div32(hi, lo, y uint32) (quo, rem uint32) { + z := uint64(hi)<<32 | uint64(lo) + quo, rem = uint32(z/uint64(y)), uint32(z%uint64(y)) + return +} + +// Div64 returns the quotient and remainder of (hi, lo) divided by y: +// quo = (hi, lo)/y, rem = (hi, lo)%y with the dividend bits' upper +// half in parameter hi and the lower half in parameter lo. +// hi must be < y otherwise the behavior is undefined (the quotient +// won't fit into quo). +func Div64(hi, lo, y uint64) (quo, rem uint64) { + const ( + two32 = 1 << 32 + mask32 = two32 - 1 + ) + if hi >= y { + return 1<<64 - 1, 1<<64 - 1 + } + + s := uint(LeadingZeros64(y)) + y <<= s + + yn1 := y >> 32 + yn0 := y & mask32 + un32 := hi<<s | lo>>(64-s) + un10 := lo << s + un1 := un10 >> 32 + un0 := un10 & mask32 + q1 := un32 / yn1 + rhat := un32 - q1*yn1 + + for q1 >= two32 || q1*yn0 > two32*rhat+un1 { + q1-- + rhat += yn1 + if rhat >= two32 { + break + } + } + + un21 := un32*two32 + un1 - q1*y + q0 := un21 / yn1 + rhat = un21 - q0*yn1 + + for q0 >= two32 || q0*yn0 > two32*rhat+un0 { + q0-- + rhat += yn1 + if rhat >= two32 { + break + } + } + + return q1*two32 + q0, (un21*two32 + un0 - q0*y) >> s +} diff --git a/src/math/bits/bits_test.go b/src/math/bits/bits_test.go index 5c34f6dbf7..bd6b618f35 100644 --- a/src/math/bits/bits_test.go +++ b/src/math/bits/bits_test.go @@ -705,6 +705,272 @@ func TestLen(t *testing.T) { } } +const ( + _M = 1<<UintSize - 1 + _M32 = 1<<32 - 1 + _M64 = 1<<64 - 1 +) + +func TestAddSubUint(t *testing.T) { + test := func(msg string, f func(x, y, c uint) (z, cout uint), x, y, c, z, cout uint) { + z1, cout1 := f(x, y, c) + if z1 != z || cout1 != cout { + t.Errorf("%s: got z:cout = %#x:%#x; want %#x:%#x", msg, z1, cout1, z, cout) + } + } + for _, a := range []struct{ x, y, c, z, cout uint }{ + {0, 0, 0, 0, 0}, + {0, 1, 0, 1, 0}, + {0, 0, 1, 1, 0}, + {0, 1, 1, 2, 0}, + {12345, 67890, 0, 80235, 0}, + {12345, 67890, 1, 80236, 0}, + {_M, 1, 0, 0, 1}, + {_M, 0, 1, 0, 1}, + {_M, 1, 1, 1, 1}, + {_M, _M, 0, _M - 1, 1}, + {_M, _M, 1, _M, 1}, + } { + test("Add", Add, a.x, a.y, a.c, a.z, a.cout) + test("Add symmetric", Add, a.y, a.x, a.c, a.z, a.cout) + test("Sub", Sub, a.z, a.x, a.c, a.y, a.cout) + test("Sub symmetric", Sub, a.z, a.y, a.c, a.x, a.cout) + } +} + +func TestAddSubUint32(t *testing.T) { + test := func(msg string, f func(x, y, c uint32) (z, cout uint32), x, y, c, z, cout uint32) { + z1, cout1 := f(x, y, c) + if z1 != z || cout1 != cout { + t.Errorf("%s: got z:cout = %#x:%#x; want %#x:%#x", msg, z1, cout1, z, cout) + } + } + for _, a := range []struct{ x, y, c, z, cout uint32 }{ + {0, 0, 0, 0, 0}, + {0, 1, 0, 1, 0}, + {0, 0, 1, 1, 0}, + {0, 1, 1, 2, 0}, + {12345, 67890, 0, 80235, 0}, + {12345, 67890, 1, 80236, 0}, + {_M32, 1, 0, 0, 1}, + {_M32, 0, 1, 0, 1}, + {_M32, 1, 1, 1, 1}, + {_M32, _M32, 0, _M32 - 1, 1}, + {_M32, _M32, 1, _M32, 1}, + } { + test("Add32", Add32, a.x, a.y, a.c, a.z, a.cout) + test("Add32 symmetric", Add32, a.y, a.x, a.c, a.z, a.cout) + test("Sub32", Sub32, a.z, a.x, a.c, a.y, a.cout) + test("Sub32 symmetric", Sub32, a.z, a.y, a.c, a.x, a.cout) + } +} + +func TestAddSubUint64(t *testing.T) { + test := func(msg string, f func(x, y, c uint64) (z, cout uint64), x, y, c, z, cout uint64) { + z1, cout1 := f(x, y, c) + if z1 != z || cout1 != cout { + t.Errorf("%s: got z:cout = %#x:%#x; want %#x:%#x", msg, z1, cout1, z, cout) + } + } + for _, a := range []struct{ x, y, c, z, cout uint64 }{ + {0, 0, 0, 0, 0}, + {0, 1, 0, 1, 0}, + {0, 0, 1, 1, 0}, + {0, 1, 1, 2, 0}, + {12345, 67890, 0, 80235, 0}, + {12345, 67890, 1, 80236, 0}, + {_M64, 1, 0, 0, 1}, + {_M64, 0, 1, 0, 1}, + {_M64, 1, 1, 1, 1}, + {_M64, _M64, 0, _M64 - 1, 1}, + {_M64, _M64, 1, _M64, 1}, + } { + test("Add64", Add64, a.x, a.y, a.c, a.z, a.cout) + test("Add64 symmetric", Add64, a.y, a.x, a.c, a.z, a.cout) + test("Sub64", Sub64, a.z, a.x, a.c, a.y, a.cout) + test("Sub64 symmetric", Sub64, a.z, a.y, a.c, a.x, a.cout) + } +} + +func TestMulDiv(t *testing.T) { + testMul := func(msg string, f func(x, y uint) (hi, lo uint), x, y, hi, lo uint) { + hi1, lo1 := f(x, y) + if hi1 != hi || lo1 != lo { + t.Errorf("%s: got hi:lo = %#x:%#x; want %#x:%#x", msg, hi1, lo1, hi, lo) + } + } + testDiv := func(msg string, f func(hi, lo, y uint) (q, r uint), hi, lo, y, q, r uint) { + q1, r1 := f(hi, lo, y) + if q1 != q || r1 != r { + t.Errorf("%s: got q:r = %#x:%#x; want %#x:%#x", msg, q1, r1, q, r) + } + } + for _, a := range []struct { + x, y uint + hi, lo, r uint + }{ + {1 << (UintSize - 1), 2, 1, 0, 1}, + {_M, _M, _M - 1, 1, 42}, + } { + testMul("Mul", Mul, a.x, a.y, a.hi, a.lo) + testMul("Mul symmetric", Mul, a.y, a.x, a.hi, a.lo) + testDiv("Div", Div, a.hi, a.lo+a.r, a.y, a.x, a.r) + testDiv("Div symmetric", Div, a.hi, a.lo+a.r, a.x, a.y, a.r) + } +} + +func TestMulDiv32(t *testing.T) { + testMul := func(msg string, f func(x, y uint32) (hi, lo uint32), x, y, hi, lo uint32) { + hi1, lo1 := f(x, y) + if hi1 != hi || lo1 != lo { + t.Errorf("%s: got hi:lo = %#x:%#x; want %#x:%#x", msg, hi1, lo1, hi, lo) + } + } + testDiv := func(msg string, f func(hi, lo, y uint32) (q, r uint32), hi, lo, y, q, r uint32) { + q1, r1 := f(hi, lo, y) + if q1 != q || r1 != r { + t.Errorf("%s: got q:r = %#x:%#x; want %#x:%#x", msg, q1, r1, q, r) + } + } + for _, a := range []struct { + x, y uint32 + hi, lo, r uint32 + }{ + {1 << 31, 2, 1, 0, 1}, + {0xc47dfa8c, 50911, 0x98a4, 0x998587f4, 13}, + {_M32, _M32, _M32 - 1, 1, 42}, + } { + testMul("Mul32", Mul32, a.x, a.y, a.hi, a.lo) + testMul("Mul32 symmetric", Mul32, a.y, a.x, a.hi, a.lo) + testDiv("Div32", Div32, a.hi, a.lo+a.r, a.y, a.x, a.r) + testDiv("Div32 symmetric", Div32, a.hi, a.lo+a.r, a.x, a.y, a.r) + } +} + +func TestMulDiv64(t *testing.T) { + testMul := func(msg string, f func(x, y uint64) (hi, lo uint64), x, y, hi, lo uint64) { + hi1, lo1 := f(x, y) + if hi1 != hi || lo1 != lo { + t.Errorf("%s: got hi:lo = %#x:%#x; want %#x:%#x", msg, hi1, lo1, hi, lo) + } + } + testDiv := func(msg string, f func(hi, lo, y uint64) (q, r uint64), hi, lo, y, q, r uint64) { + q1, r1 := f(hi, lo, y) + if q1 != q || r1 != r { + t.Errorf("%s: got q:r = %#x:%#x; want %#x:%#x", msg, q1, r1, q, r) + } + } + for _, a := range []struct { + x, y uint64 + hi, lo, r uint64 + }{ + {1 << 63, 2, 1, 0, 1}, + {0x3626229738a3b9, 0xd8988a9f1cc4a61, 0x2dd0712657fe8, 0x9dd6a3364c358319, 13}, + {_M64, _M64, _M64 - 1, 1, 42}, + } { + testMul("Mul64", Mul64, a.x, a.y, a.hi, a.lo) + testMul("Mul64 symmetric", Mul64, a.y, a.x, a.hi, a.lo) + testDiv("Div64", Div64, a.hi, a.lo+a.r, a.y, a.x, a.r) + testDiv("Div64 symmetric", Div64, a.hi, a.lo+a.r, a.x, a.y, a.r) + } +} + +func BenchmarkAdd(b *testing.B) { + var z, c uint + for i := 0; i < b.N; i++ { + z, c = Add(uint(Input), uint(i), c) + } + Output = int(z + c) +} + +func BenchmarkAdd32(b *testing.B) { + var z, c uint32 + for i := 0; i < b.N; i++ { + z, c = Add32(uint32(Input), uint32(i), c) + } + Output = int(z + c) +} + +func BenchmarkAdd64(b *testing.B) { + var z, c uint64 + for i := 0; i < b.N; i++ { + z, c = Add64(uint64(Input), uint64(i), c) + } + Output = int(z + c) +} + +func BenchmarkSub(b *testing.B) { + var z, c uint + for i := 0; i < b.N; i++ { + z, c = Sub(uint(Input), uint(i), c) + } + Output = int(z + c) +} + +func BenchmarkSub32(b *testing.B) { + var z, c uint32 + for i := 0; i < b.N; i++ { + z, c = Sub32(uint32(Input), uint32(i), c) + } + Output = int(z + c) +} + +func BenchmarkSub64(b *testing.B) { + var z, c uint64 + for i := 0; i < b.N; i++ { + z, c = Add64(uint64(Input), uint64(i), c) + } + Output = int(z + c) +} + +func BenchmarkMul(b *testing.B) { + var hi, lo uint + for i := 0; i < b.N; i++ { + hi, lo = Mul(uint(Input), uint(i)) + } + Output = int(hi + lo) +} + +func BenchmarkMul32(b *testing.B) { + var hi, lo uint32 + for i := 0; i < b.N; i++ { + hi, lo = Mul32(uint32(Input), uint32(i)) + } + Output = int(hi + lo) +} + +func BenchmarkMul64(b *testing.B) { + var hi, lo uint64 + for i := 0; i < b.N; i++ { + hi, lo = Mul64(uint64(Input), uint64(i)) + } + Output = int(hi + lo) +} + +func BenchmarkDiv(b *testing.B) { + var q, r uint + for i := 0; i < b.N; i++ { + q, r = Div(1, uint(i), uint(Input)) + } + Output = int(q + r) +} + +func BenchmarkDiv32(b *testing.B) { + var q, r uint32 + for i := 0; i < b.N; i++ { + q, r = Div32(1, uint32(i), uint32(Input)) + } + Output = int(q + r) +} + +func BenchmarkDiv64(b *testing.B) { + var q, r uint64 + for i := 0; i < b.N; i++ { + q, r = Div64(1, uint64(i), uint64(Input)) + } + Output = int(q + r) +} + // ---------------------------------------------------------------------------- // Testing support diff --git a/src/math/expm1_386.s b/src/math/expm1_386.s index c1392cd52b..d020296ca7 100644 --- a/src/math/expm1_386.s +++ b/src/math/expm1_386.s @@ -8,7 +8,7 @@ TEXT ·Expm1(SB),NOSPLIT,$0 FLDLN2 // F0=log(2) = 1/log2(e) ~ 0.693147 FMOVD x+0(FP), F0 // F0=x, F1=1/log2(e) - FABS // F0=|x|, F1=1/log2(e) + FABS // F0=|x|, F1=1/log2(e) FUCOMPP F0, F1 // compare F0 to F1 FSTSW AX SAHF @@ -36,7 +36,7 @@ use_exp: FSCALE // F0=e**x, F1=int(x*log2(e)) FMOVDP F0, F1 // F0=e**x FLD1 // F0=1, F1=e**x - FSUBDP F0, F1 // F0=e**x-1 + FSUBDP F0, F1 // F0=e**x-1 FMOVDP F0, ret+8(FP) RET not_finite: diff --git a/src/math/sin_386.s b/src/math/sin_386.s index 9d605a1e38..45d12e00c8 100644 --- a/src/math/sin_386.s +++ b/src/math/sin_386.s @@ -24,7 +24,7 @@ TEXT ·Cos(SB),NOSPLIT,$0 FCOS // F0=cos(reduced_x) FMOVDP F0, ret+8(FP) RET - + // func Sin(x float64) float64 TEXT ·Sin(SB),NOSPLIT,$0 FMOVD x+0(FP), F0 // F0=x diff --git a/src/math/sqrt_386.s b/src/math/sqrt_386.s index 402d152785..5a5c33a79a 100644 --- a/src/math/sqrt_386.s +++ b/src/math/sqrt_386.s @@ -4,7 +4,7 @@ #include "textflag.h" -// func Sqrt(x float64) float64 +// func Sqrt(x float64) float64 TEXT ·Sqrt(SB),NOSPLIT,$0 FMOVD x+0(FP),F0 FSQRT diff --git a/src/math/sqrt_arm.s b/src/math/sqrt_arm.s index deb6712553..ffc7d1026d 100644 --- a/src/math/sqrt_arm.s +++ b/src/math/sqrt_arm.s @@ -4,7 +4,7 @@ #include "textflag.h" -// func Sqrt(x float64) float64 +// func Sqrt(x float64) float64 TEXT ·Sqrt(SB),NOSPLIT,$0 MOVB runtime·goarm(SB), R11 CMP $5, R11 diff --git a/src/mime/mediatype.go b/src/mime/mediatype.go index ea2bbac189..3d480a9d7e 100644 --- a/src/mime/mediatype.go +++ b/src/mime/mediatype.go @@ -280,7 +280,7 @@ func consumeValue(v string) (value, rest string) { // and intended as a literal backslash. This makes Go servers deal better // with MSIE without affecting the way they handle conforming MIME // generators. - if r == '\\' && i+1 < len(v) && !isTokenChar(rune(v[i+1])) { + if r == '\\' && i+1 < len(v) && isTSpecial(rune(v[i+1])) { buffer.WriteByte(v[i+1]) i++ continue diff --git a/src/mime/mediatype_test.go b/src/mime/mediatype_test.go index 88d742f0aa..35b311a4a5 100644 --- a/src/mime/mediatype_test.go +++ b/src/mime/mediatype_test.go @@ -40,6 +40,8 @@ func TestConsumeValue(t *testing.T) { {`"\\" rest`, "\\", " rest"}, {`"My \" value"end`, "My \" value", "end"}, {`"\" rest`, "", `"\" rest`}, + {`"C:\dev\go\robots.txt"`, `C:\dev\go\robots.txt`, ""}, + {`"C:\新建文件件\中文第二次测试.mp4"`, `C:\新建文件件\中文第二次测试.mp4`, ""}, } for _, test := range tests { value, rest := consumeValue(test[0]) @@ -393,6 +395,7 @@ func TestParseMediaType(t *testing.T) { // Microsoft browers in intranet mode do not think they need to escape \ in file name. {`form-data; name="file"; filename="C:\dev\go\robots.txt"`, "form-data", m("name", "file", "filename", `C:\dev\go\robots.txt`)}, + {`form-data; name="file"; filename="C:\新建文件件\中文第二次测试.mp4"`, "form-data", m("name", "file", "filename", `C:\新建文件件\中文第二次测试.mp4`)}, } for _, test := range tests { mt, params, err := ParseMediaType(test.in) diff --git a/src/mime/multipart/formdata_test.go b/src/mime/multipart/formdata_test.go index 2d6a830cb6..105a82c417 100644 --- a/src/mime/multipart/formdata_test.go +++ b/src/mime/multipart/formdata_test.go @@ -13,7 +13,7 @@ import ( ) func TestReadForm(t *testing.T) { - b := strings.NewReader(strings.Replace(message, "\n", "\r\n", -1)) + b := strings.NewReader(strings.ReplaceAll(message, "\n", "\r\n")) r := NewReader(b, boundary) f, err := r.ReadForm(25) if err != nil { @@ -39,7 +39,7 @@ func TestReadForm(t *testing.T) { } func TestReadFormWithNamelessFile(t *testing.T) { - b := strings.NewReader(strings.Replace(messageWithFileWithoutName, "\n", "\r\n", -1)) + b := strings.NewReader(strings.ReplaceAll(messageWithFileWithoutName, "\n", "\r\n")) r := NewReader(b, boundary) f, err := r.ReadForm(25) if err != nil { @@ -54,7 +54,7 @@ func TestReadFormWithNamelessFile(t *testing.T) { func TestReadFormWithTextContentType(t *testing.T) { // From https://github.com/golang/go/issues/24041 - b := strings.NewReader(strings.Replace(messageWithTextContentType, "\n", "\r\n", -1)) + b := strings.NewReader(strings.ReplaceAll(messageWithTextContentType, "\n", "\r\n")) r := NewReader(b, boundary) f, err := r.ReadForm(25) if err != nil { @@ -184,7 +184,7 @@ Content-Disposition: form-data; name="largetext" --MyBoundary-- ` - testBody := strings.Replace(message, "\n", "\r\n", -1) + testBody := strings.ReplaceAll(message, "\n", "\r\n") testCases := []struct { name string maxMemory int64 diff --git a/src/mime/multipart/multipart_test.go b/src/mime/multipart/multipart_test.go index abe1cc8e77..7bf606765c 100644 --- a/src/mime/multipart/multipart_test.go +++ b/src/mime/multipart/multipart_test.go @@ -105,7 +105,7 @@ never read data useless trailer ` - testBody = strings.Replace(testBody, "\n", sep, -1) + testBody = strings.ReplaceAll(testBody, "\n", sep) return strings.Replace(testBody, "[longline]", longLine, 1) } @@ -151,7 +151,7 @@ func testMultipart(t *testing.T, r io.Reader, onlyNewlines bool) { adjustNewlines := func(s string) string { if onlyNewlines { - return strings.Replace(s, "\r\n", "\n", -1) + return strings.ReplaceAll(s, "\r\n", "\n") } return s } @@ -299,7 +299,7 @@ foo-bar: baz Oh no, premature EOF! ` - body := strings.Replace(testBody, "\n", "\r\n", -1) + body := strings.ReplaceAll(testBody, "\n", "\r\n") bodyReader := strings.NewReader(body) r := NewReader(bodyReader, "MyBoundary") diff --git a/src/net/dnsclient.go b/src/net/dnsclient.go index e3524280b6..2c47bc4130 100644 --- a/src/net/dnsclient.go +++ b/src/net/dnsclient.go @@ -75,7 +75,7 @@ func isDomainName(s string) bool { } last := byte('.') - ok := false // Ok once we've seen a letter. + nonNumeric := false // true once we've seen a letter or hyphen partlen := 0 for i := 0; i < len(s); i++ { c := s[i] @@ -83,7 +83,7 @@ func isDomainName(s string) bool { default: return false case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z' || c == '_': - ok = true + nonNumeric = true partlen++ case '0' <= c && c <= '9': // fine @@ -94,6 +94,7 @@ func isDomainName(s string) bool { return false } partlen++ + nonNumeric = true case c == '.': // Byte before dot cannot be dot, dash. if last == '.' || last == '-' { @@ -110,7 +111,7 @@ func isDomainName(s string) bool { return false } - return ok + return nonNumeric } // absDomainName returns an absolute domain name which ends with a diff --git a/src/net/dnsclient_unix.go b/src/net/dnsclient_unix.go index 2fee3346e9..9a0b1d69a8 100644 --- a/src/net/dnsclient_unix.go +++ b/src/net/dnsclient_unix.go @@ -27,6 +27,20 @@ import ( "golang_org/x/net/dns/dnsmessage" ) +var ( + errLameReferral = errors.New("lame referral") + errCannotUnmarshalDNSMessage = errors.New("cannot unmarshal DNS message") + errCannotMarshalDNSMessage = errors.New("cannot marshal DNS message") + errServerMisbehaving = errors.New("server misbehaving") + errInvalidDNSResponse = errors.New("invalid DNS response") + errNoAnswerFromDNSServer = errors.New("no answer from DNS server") + + // errServerTemporarlyMisbehaving is like errServerMisbehaving, except + // that when it gets translated to a DNSError, the IsTemporary field + // gets set to true. + errServerTemporarlyMisbehaving = errors.New("server misbehaving") +) + func newRequest(q dnsmessage.Question) (id uint16, udpReq, tcpReq []byte, err error) { id = uint16(rand.Int()) ^ uint16(time.Now().UnixNano()) b := dnsmessage.NewBuilder(make([]byte, 2, 514), dnsmessage.Header{ID: id, RecursionDesired: true}) @@ -105,14 +119,14 @@ func dnsStreamRoundTrip(c Conn, id uint16, query dnsmessage.Question, b []byte) var p dnsmessage.Parser h, err := p.Start(b[:n]) if err != nil { - return dnsmessage.Parser{}, dnsmessage.Header{}, errors.New("cannot unmarshal DNS message") + return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotUnmarshalDNSMessage } q, err := p.Question() if err != nil { - return dnsmessage.Parser{}, dnsmessage.Header{}, errors.New("cannot unmarshal DNS message") + return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotUnmarshalDNSMessage } if !checkResponse(id, query, h, q) { - return dnsmessage.Parser{}, dnsmessage.Header{}, errors.New("invalid DNS response") + return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse } return p, h, nil } @@ -122,7 +136,7 @@ func (r *Resolver) exchange(ctx context.Context, server string, q dnsmessage.Que q.Class = dnsmessage.ClassINET id, udpReq, tcpReq, err := newRequest(q) if err != nil { - return dnsmessage.Parser{}, dnsmessage.Header{}, errors.New("cannot marshal DNS message") + return dnsmessage.Parser{}, dnsmessage.Header{}, errCannotMarshalDNSMessage } for _, network := range []string{"udp", "tcp"} { ctx, cancel := context.WithDeadline(ctx, time.Now().Add(timeout)) @@ -147,31 +161,31 @@ func (r *Resolver) exchange(ctx context.Context, server string, q dnsmessage.Que return dnsmessage.Parser{}, dnsmessage.Header{}, mapErr(err) } if err := p.SkipQuestion(); err != dnsmessage.ErrSectionDone { - return dnsmessage.Parser{}, dnsmessage.Header{}, errors.New("invalid DNS response") + return dnsmessage.Parser{}, dnsmessage.Header{}, errInvalidDNSResponse } if h.Truncated { // see RFC 5966 continue } return p, h, nil } - return dnsmessage.Parser{}, dnsmessage.Header{}, errors.New("no answer from DNS server") + return dnsmessage.Parser{}, dnsmessage.Header{}, errNoAnswerFromDNSServer } // checkHeader performs basic sanity checks on the header. func checkHeader(p *dnsmessage.Parser, h dnsmessage.Header, name, server string) error { + if h.RCode == dnsmessage.RCodeNameError { + return errNoSuchHost + } + _, err := p.AnswerHeader() if err != nil && err != dnsmessage.ErrSectionDone { - return &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } + return errCannotUnmarshalDNSMessage } // libresolv continues to the next server when it receives // an invalid referral response. See golang.org/issue/15434. if h.RCode == dnsmessage.RCodeSuccess && !h.Authoritative && !h.RecursionAvailable && err == dnsmessage.ErrSectionDone { - return &DNSError{Err: "lame referral", Name: name, Server: server} + return errLameReferral } if h.RCode != dnsmessage.RCodeSuccess && h.RCode != dnsmessage.RCodeNameError { @@ -180,11 +194,10 @@ func checkHeader(p *dnsmessage.Parser, h dnsmessage.Header, name, server string) // a name error and we didn't get success, // the server is behaving incorrectly or // having temporary trouble. - err := &DNSError{Err: "server misbehaving", Name: name, Server: server} if h.RCode == dnsmessage.RCodeServerFailure { - err.IsTemporary = true + return errServerTemporarlyMisbehaving } - return err + return errServerMisbehaving } return nil @@ -194,28 +207,16 @@ func skipToAnswer(p *dnsmessage.Parser, qtype dnsmessage.Type, name, server stri for { h, err := p.AnswerHeader() if err == dnsmessage.ErrSectionDone { - return &DNSError{ - Err: errNoSuchHost.Error(), - Name: name, - Server: server, - } + return errNoSuchHost } if err != nil { - return &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } + return errCannotUnmarshalDNSMessage } if h.Type == qtype { return nil } if err := p.SkipAnswer(); err != nil { - return &DNSError{ - Err: "cannot unmarshal DNS message", - Name: name, - Server: server, - } + return errCannotUnmarshalDNSMessage } } } @@ -229,7 +230,7 @@ func (r *Resolver) tryOneName(ctx context.Context, cfg *dnsConfig, name string, n, err := dnsmessage.NewName(name) if err != nil { - return dnsmessage.Parser{}, "", errors.New("cannot marshal DNS message") + return dnsmessage.Parser{}, "", errCannotMarshalDNSMessage } q := dnsmessage.Question{ Name: n, @@ -243,38 +244,62 @@ func (r *Resolver) tryOneName(ctx context.Context, cfg *dnsConfig, name string, p, h, err := r.exchange(ctx, server, q, cfg.timeout) if err != nil { - lastErr = &DNSError{ + dnsErr := &DNSError{ Err: err.Error(), Name: name, Server: server, } if nerr, ok := err.(Error); ok && nerr.Timeout() { - lastErr.(*DNSError).IsTimeout = true + dnsErr.IsTimeout = true } // Set IsTemporary for socket-level errors. Note that this flag // may also be used to indicate a SERVFAIL response. if _, ok := err.(*OpError); ok { - lastErr.(*DNSError).IsTemporary = true + dnsErr.IsTemporary = true } + lastErr = dnsErr continue } - // The name does not exist, so trying another server won't help. - // - // TODO: indicate this in a more obvious way, such as a field on DNSError? - if h.RCode == dnsmessage.RCodeNameError { - return dnsmessage.Parser{}, "", &DNSError{Err: errNoSuchHost.Error(), Name: name, Server: server} - } - - lastErr = checkHeader(&p, h, name, server) - if lastErr != nil { + if err := checkHeader(&p, h, name, server); err != nil { + dnsErr := &DNSError{ + Err: err.Error(), + Name: name, + Server: server, + } + if err == errServerTemporarlyMisbehaving { + dnsErr.IsTemporary = true + } + if err == errNoSuchHost { + // The name does not exist, so trying + // another server won't help. + // + // TODO: indicate this in a more + // obvious way, such as a field on + // DNSError? + return p, server, dnsErr + } + lastErr = dnsErr continue } - lastErr = skipToAnswer(&p, qtype, name, server) - if lastErr == nil { + err = skipToAnswer(&p, qtype, name, server) + if err == nil { return p, server, nil } + lastErr = &DNSError{ + Err: err.Error(), + Name: name, + Server: server, + } + if err == errNoSuchHost { + // The name does not exist, so trying another + // server won't help. + // + // TODO: indicate this in a more obvious way, + // such as a field on DNSError? + return p, server, lastErr + } } } return dnsmessage.Parser{}, "", lastErr diff --git a/src/net/dnsclient_unix_test.go b/src/net/dnsclient_unix_test.go index bb014b903a..9482fc466f 100644 --- a/src/net/dnsclient_unix_test.go +++ b/src/net/dnsclient_unix_test.go @@ -1427,28 +1427,35 @@ func TestDNSGoroutineRace(t *testing.T) { } } +func lookupWithFake(fake fakeDNSServer, name string, typ dnsmessage.Type) error { + r := Resolver{PreferGo: true, Dial: fake.DialContext} + + resolvConf.mu.RLock() + conf := resolvConf.dnsConfig + resolvConf.mu.RUnlock() + + ctx, cancel := context.WithCancel(context.Background()) + defer cancel() + + _, _, err := r.tryOneName(ctx, conf, name, typ) + return err +} + // Issue 8434: verify that Temporary returns true on an error when rcode // is SERVFAIL func TestIssue8434(t *testing.T) { - msg := dnsmessage.Message{ - Header: dnsmessage.Header{ - RCode: dnsmessage.RCodeServerFailure, + err := lookupWithFake(fakeDNSServer{ + rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) { + return dnsmessage.Message{ + Header: dnsmessage.Header{ + ID: q.ID, + Response: true, + RCode: dnsmessage.RCodeServerFailure, + }, + Questions: q.Questions, + }, nil }, - } - b, err := msg.Pack() - if err != nil { - t.Fatal("Pack failed:", err) - } - var p dnsmessage.Parser - h, err := p.Start(b) - if err != nil { - t.Fatal("Start failed:", err) - } - if err := p.SkipAllQuestions(); err != nil { - t.Fatal("SkipAllQuestions failed:", err) - } - - err = checkHeader(&p, h, "golang.org", "foo:53") + }, "golang.org.", dnsmessage.TypeALL) if err == nil { t.Fatal("expected an error") } @@ -1464,50 +1471,76 @@ func TestIssue8434(t *testing.T) { } } -// Issue 12778: verify that NXDOMAIN without RA bit errors as -// "no such host" and not "server misbehaving" +// TestNoSuchHost verifies that tryOneName works correctly when the domain does +// not exist. +// +// Issue 12778: verify that NXDOMAIN without RA bit errors as "no such host" +// and not "server misbehaving" // // Issue 25336: verify that NXDOMAIN errors fail fast. -func TestIssue12778(t *testing.T) { - lookups := 0 - fake := fakeDNSServer{ - rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) { - lookups++ - return dnsmessage.Message{ - Header: dnsmessage.Header{ - ID: q.ID, - Response: true, - RCode: dnsmessage.RCodeNameError, - RecursionAvailable: false, - }, - Questions: q.Questions, - }, nil +// +// Issue 27525: verify that empty answers fail fast. +func TestNoSuchHost(t *testing.T) { + tests := []struct { + name string + f func(string, string, dnsmessage.Message, time.Time) (dnsmessage.Message, error) + }{ + { + "NXDOMAIN", + func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) { + return dnsmessage.Message{ + Header: dnsmessage.Header{ + ID: q.ID, + Response: true, + RCode: dnsmessage.RCodeNameError, + RecursionAvailable: false, + }, + Questions: q.Questions, + }, nil + }, + }, + { + "no answers", + func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) { + return dnsmessage.Message{ + Header: dnsmessage.Header{ + ID: q.ID, + Response: true, + RCode: dnsmessage.RCodeSuccess, + RecursionAvailable: false, + Authoritative: true, + }, + Questions: q.Questions, + }, nil + }, }, } - r := Resolver{PreferGo: true, Dial: fake.DialContext} - - resolvConf.mu.RLock() - conf := resolvConf.dnsConfig - resolvConf.mu.RUnlock() - - ctx, cancel := context.WithCancel(context.Background()) - defer cancel() - _, _, err := r.tryOneName(ctx, conf, ".", dnsmessage.TypeALL) + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + lookups := 0 + err := lookupWithFake(fakeDNSServer{ + rh: func(n, s string, q dnsmessage.Message, d time.Time) (dnsmessage.Message, error) { + lookups++ + return test.f(n, s, q, d) + }, + }, ".", dnsmessage.TypeALL) - if lookups != 1 { - t.Errorf("got %d lookups, wanted 1", lookups) - } + if lookups != 1 { + t.Errorf("got %d lookups, wanted 1", lookups) + } - if err == nil { - t.Fatal("expected an error") - } - de, ok := err.(*DNSError) - if !ok { - t.Fatalf("err = %#v; wanted a *net.DNSError", err) - } - if de.Err != errNoSuchHost.Error() { - t.Fatalf("Err = %#v; wanted %q", de.Err, errNoSuchHost.Error()) + if err == nil { + t.Fatal("expected an error") + } + de, ok := err.(*DNSError) + if !ok { + t.Fatalf("err = %#v; wanted a *net.DNSError", err) + } + if de.Err != errNoSuchHost.Error() { + t.Fatalf("Err = %#v; wanted %q", de.Err, errNoSuchHost.Error()) + } + }) } } @@ -1535,3 +1568,56 @@ func TestDNSDialTCP(t *testing.T) { t.Fatal("exhange failed:", err) } } + +// Issue 27763: verify that two strings in one TXT record are concatenated. +func TestTXTRecordTwoStrings(t *testing.T) { + fake := fakeDNSServer{ + rh: func(n, _ string, q dnsmessage.Message, _ time.Time) (dnsmessage.Message, error) { + r := dnsmessage.Message{ + Header: dnsmessage.Header{ + ID: q.Header.ID, + Response: true, + RCode: dnsmessage.RCodeSuccess, + }, + Questions: q.Questions, + Answers: []dnsmessage.Resource{ + { + Header: dnsmessage.ResourceHeader{ + Name: q.Questions[0].Name, + Type: dnsmessage.TypeA, + Class: dnsmessage.ClassINET, + }, + Body: &dnsmessage.TXTResource{ + TXT: []string{"string1 ", "string2"}, + }, + }, + { + Header: dnsmessage.ResourceHeader{ + Name: q.Questions[0].Name, + Type: dnsmessage.TypeA, + Class: dnsmessage.ClassINET, + }, + Body: &dnsmessage.TXTResource{ + TXT: []string{"onestring"}, + }, + }, + }, + } + return r, nil + }, + } + r := Resolver{PreferGo: true, Dial: fake.DialContext} + txt, err := r.lookupTXT(context.Background(), "golang.org") + if err != nil { + t.Fatal("LookupTXT failed:", err) + } + if want := 2; len(txt) != want { + t.Fatalf("len(txt), got %d, want %d", len(txt), want) + } + if want := "string1 string2"; txt[0] != want { + t.Errorf("txt[0], got %q, want %q", txt[0], want) + } + if want := "onestring"; txt[1] != want { + t.Errorf("txt[1], got %q, want %q", txt[1], want) + } +} diff --git a/src/net/dnsname_test.go b/src/net/dnsname_test.go index 806d8756cb..2964982311 100644 --- a/src/net/dnsname_test.go +++ b/src/net/dnsname_test.go @@ -22,6 +22,7 @@ var dnsNameTests = []dnsNameTest{ {"foo.com", true}, {"1foo.com", true}, {"26.0.0.73.com", true}, + {"10-0-0-1", true}, {"fo-o.com", true}, {"fo1o.com", true}, {"foo1.com", true}, diff --git a/src/net/http/cgi/child.go b/src/net/http/cgi/child.go index da12ac3498..10325c2eb5 100644 --- a/src/net/http/cgi/child.go +++ b/src/net/http/cgi/child.go @@ -86,7 +86,7 @@ func RequestFromMap(params map[string]string) (*http.Request, error) { if !strings.HasPrefix(k, "HTTP_") || k == "HTTP_HOST" { continue } - r.Header.Add(strings.Replace(k[5:], "_", "-", -1), v) + r.Header.Add(strings.ReplaceAll(k[5:], "_", "-"), v) } // TODO: cookies. parsing them isn't exported, though. diff --git a/src/net/http/client.go b/src/net/http/client.go index a15b3ba276..ea6c071911 100644 --- a/src/net/http/client.go +++ b/src/net/http/client.go @@ -238,7 +238,7 @@ func send(ireq *Request, rt RoundTripper, deadline time.Time) (resp *Response, d username := u.Username() password, _ := u.Password() forkReq() - req.Header = cloneHeader(ireq.Header) + req.Header = ireq.Header.clone() req.Header.Set("Authorization", "Basic "+basicAuth(username, password)) } diff --git a/src/net/http/clientserver_test.go b/src/net/http/clientserver_test.go index 9a05b648e3..465bae1478 100644 --- a/src/net/http/clientserver_test.go +++ b/src/net/http/clientserver_test.go @@ -252,7 +252,7 @@ type slurpResult struct { func (sr slurpResult) String() string { return fmt.Sprintf("body %q; err %v", sr.body, sr.err) } func (tt h12Compare) normalizeRes(t *testing.T, res *Response, wantProto string) { - if res.Proto == wantProto { + if res.Proto == wantProto || res.Proto == "HTTP/IGNORE" { res.Proto, res.ProtoMajor, res.ProtoMinor = "", 0, 0 } else { t.Errorf("got %q response; want %q", res.Proto, wantProto) @@ -1474,11 +1474,11 @@ func testWriteHeaderAfterWrite(t *testing.T, h2, hijack bool) { return } gotLog := strings.TrimSpace(errorLog.String()) - wantLog := "http: multiple response.WriteHeader calls" + wantLog := "http: superfluous response.WriteHeader call from net/http_test.testWriteHeaderAfterWrite.func1 (clientserver_test.go:" if hijack { - wantLog = "http: response.WriteHeader on hijacked connection" + wantLog = "http: response.WriteHeader on hijacked connection from net/http_test.testWriteHeaderAfterWrite.func1 (clientserver_test.go:" } - if gotLog != wantLog { + if !strings.HasPrefix(gotLog, wantLog) { t.Errorf("stderr output = %q; want %q", gotLog, wantLog) } } @@ -1546,3 +1546,25 @@ func TestBidiStreamReverseProxy(t *testing.T) { } } + +// Always use HTTP/1.1 for WebSocket upgrades. +func TestH12_WebSocketUpgrade(t *testing.T) { + h12Compare{ + Handler: func(w ResponseWriter, r *Request) { + h := w.Header() + h.Set("Foo", "bar") + }, + ReqFunc: func(c *Client, url string) (*Response, error) { + req, _ := NewRequest("GET", url, nil) + req.Header.Set("Connection", "Upgrade") + req.Header.Set("Upgrade", "WebSocket") + return c.Do(req) + }, + EarlyCheckResponse: func(proto string, res *Response) { + if res.Proto != "HTTP/1.1" { + t.Errorf("%s: expected HTTP/1.1, got %q", proto, res.Proto) + } + res.Proto = "HTTP/IGNORE" // skip later checks that Proto must be 1.1 vs 2.0 + }, + }.run(t) +} diff --git a/src/net/http/cookie.go b/src/net/http/cookie.go index 382398756b..289c3c37b1 100644 --- a/src/net/http/cookie.go +++ b/src/net/http/cookie.go @@ -36,9 +36,9 @@ type Cookie struct { Unparsed []string // Raw text of unparsed attribute-value pairs } -// SameSite allows a server define a cookie attribute making it impossible for +// SameSite allows a server to define a cookie attribute making it impossible for // the browser to send this cookie along with cross-site requests. The main -// goal is mitigate the risk of cross-origin information leakage, and provides +// goal is to mitigate the risk of cross-origin information leakage, and provides // some protection against cross-site request forgery attacks. // // See https://tools.ietf.org/html/draft-ietf-httpbis-cookie-same-site-00 for details. diff --git a/src/net/http/example_handle_test.go b/src/net/http/example_handle_test.go new file mode 100644 index 0000000000..10a62f64c2 --- /dev/null +++ b/src/net/http/example_handle_test.go @@ -0,0 +1,29 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package http_test + +import ( + "fmt" + "log" + "net/http" + "sync" +) + +type countHandler struct { + mu sync.Mutex // guards n + n int +} + +func (h *countHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) { + h.mu.Lock() + defer h.mu.Unlock() + h.n++ + fmt.Fprintf(w, "count is %d\n", h.n) +} + +func ExampleHandle() { + http.Handle("/count", new(countHandler)) + log.Fatal(http.ListenAndServe(":8080", nil)) +} diff --git a/src/net/http/example_test.go b/src/net/http/example_test.go index f5c47d0bd4..2a09f5f6c6 100644 --- a/src/net/http/example_test.go +++ b/src/net/http/example_test.go @@ -173,3 +173,21 @@ func ExampleHandleFunc() { log.Fatal(http.ListenAndServe(":8080", nil)) } + +func newPeopleHandler() http.Handler { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + fmt.Fprintln(w, "This is the people handler.") + }) +} + +func ExampleNotFoundHandler() { + mux := http.NewServeMux() + + // Create sample handler to returns 404 + mux.Handle("/resources", http.NotFoundHandler()) + + // Create sample handler that returns 200 + mux.Handle("/resources/people/", newPeopleHandler()) + + log.Fatal(http.ListenAndServe(":8080", mux)) +} diff --git a/src/net/http/export_test.go b/src/net/http/export_test.go index bc0db53a2c..716e8ecac7 100644 --- a/src/net/http/export_test.go +++ b/src/net/http/export_test.go @@ -155,7 +155,7 @@ func (t *Transport) IdleConnStrsForTesting_h2() []string { func (t *Transport) IdleConnCountForTesting(scheme, addr string) int { t.idleMu.Lock() defer t.idleMu.Unlock() - key := connectMethodKey{"", scheme, addr} + key := connectMethodKey{"", scheme, addr, false} cacheKey := key.String() for k, conns := range t.idleConn { if k.String() == cacheKey { @@ -178,12 +178,12 @@ func (t *Transport) IsIdleForTesting() bool { } func (t *Transport) RequestIdleConnChForTesting() { - t.getIdleConnCh(connectMethod{nil, "http", "example.com"}) + t.getIdleConnCh(connectMethod{nil, "http", "example.com", false}) } func (t *Transport) PutIdleTestConn(scheme, addr string) bool { c, _ := net.Pipe() - key := connectMethodKey{"", scheme, addr} + key := connectMethodKey{"", scheme, addr, false} select { case <-t.incHostConnCount(key): default: diff --git a/src/net/http/header.go b/src/net/http/header.go index b28144d8c1..611ee04705 100644 --- a/src/net/http/header.go +++ b/src/net/http/header.go @@ -19,23 +19,27 @@ type Header map[string][]string // Add adds the key, value pair to the header. // It appends to any existing values associated with key. +// The key is case insensitive; it is canonicalized by +// textproto.CanonicalMIMEHeaderKey. func (h Header) Add(key, value string) { textproto.MIMEHeader(h).Add(key, value) } -// Set sets the header entries associated with key to -// the single element value. It replaces any existing -// values associated with key. +// Set sets the header entries associated with key to the +// single element value. It replaces any existing values +// associated with key. The key is case insensitive; it is +// canonicalized by textproto.CanonicalMIMEHeaderKey. +// To use non-canonical keys, assign to the map directly. func (h Header) Set(key, value string) { textproto.MIMEHeader(h).Set(key, value) } -// Get gets the first value associated with the given key. -// It is case insensitive; textproto.CanonicalMIMEHeaderKey is used -// to canonicalize the provided key. -// If there are no values associated with the key, Get returns "". -// To access multiple values of a key, or to use non-canonical keys, -// access the map directly. +// Get gets the first value associated with the given key. If +// there are no values associated with the key, Get returns "". +// It is case insensitive; textproto.CanonicalMIMEHeaderKey is +// used to canonicalize the provided key. To access multiple +// values of a key, or to use non-canonical keys, access the +// map directly. func (h Header) Get(key string) string { return textproto.MIMEHeader(h).Get(key) } @@ -49,6 +53,8 @@ func (h Header) get(key string) string { } // Del deletes the values associated with key. +// The key is case insensitive; it is canonicalized by +// textproto.CanonicalMIMEHeaderKey. func (h Header) Del(key string) { textproto.MIMEHeader(h).Del(key) } @@ -93,10 +99,6 @@ func ParseTime(text string) (t time.Time, err error) { var headerNewlineToSpace = strings.NewReplacer("\n", " ", "\r", " ") -type writeStringer interface { - WriteString(string) (int, error) -} - // stringWriter implements WriteString on a Writer. type stringWriter struct { w io.Writer @@ -152,7 +154,7 @@ func (h Header) WriteSubset(w io.Writer, exclude map[string]bool) error { } func (h Header) writeSubset(w io.Writer, exclude map[string]bool, trace *httptrace.ClientTrace) error { - ws, ok := w.(writeStringer) + ws, ok := w.(io.StringWriter) if !ok { ws = stringWriter{w} } @@ -229,13 +231,3 @@ func hasToken(v, token string) bool { func isTokenBoundary(b byte) bool { return b == ' ' || b == ',' || b == '\t' } - -func cloneHeader(h Header) Header { - h2 := make(Header, len(h)) - for k, vv := range h { - vv2 := make([]string, len(vv)) - copy(vv2, vv) - h2[k] = vv2 - } - return h2 -} diff --git a/src/net/http/http.go b/src/net/http/http.go index ce0eceb1de..30d1a52b63 100644 --- a/src/net/http/http.go +++ b/src/net/http/http.go @@ -135,6 +135,10 @@ type Pusher interface { // data that may trigger a request for URL X. This avoids a race where the // client issues requests for X before receiving the PUSH_PROMISE for X. // + // Push will run in a separate goroutine making the order of arrival + // non-deterministic. Any required synchronization needs to be implemented + // by the caller. + // // Push returns ErrNotSupported if the client has disabled push or if push // is not supported on the underlying connection. Push(target string, opts *PushOptions) error diff --git a/src/net/http/httputil/dump_test.go b/src/net/http/httputil/dump_test.go index 5703a7fb86..63312dd885 100644 --- a/src/net/http/httputil/dump_test.go +++ b/src/net/http/httputil/dump_test.go @@ -370,7 +370,7 @@ func TestDumpResponse(t *testing.T) { } got := string(gotb) got = strings.TrimSpace(got) - got = strings.Replace(got, "\r", "", -1) + got = strings.ReplaceAll(got, "\r", "") if got != tt.want { t.Errorf("%d.\nDumpResponse got:\n%s\n\nWant:\n%s\n", i, got, tt.want) diff --git a/src/net/http/proxy_test.go b/src/net/http/proxy_test.go index eef0ca82f8..feb7047a58 100644 --- a/src/net/http/proxy_test.go +++ b/src/net/http/proxy_test.go @@ -35,7 +35,7 @@ func TestCacheKeys(t *testing.T) { } proxy = u } - cm := connectMethod{proxy, tt.scheme, tt.addr} + cm := connectMethod{proxy, tt.scheme, tt.addr, false} if got := cm.key().String(); got != tt.key { t.Fatalf("{%q, %q, %q} cache key = %q; want %q", tt.proxy, tt.scheme, tt.addr, got, tt.key) } diff --git a/src/net/http/readrequest_test.go b/src/net/http/readrequest_test.go index 18eed345a8..517a8189e1 100644 --- a/src/net/http/readrequest_test.go +++ b/src/net/http/readrequest_test.go @@ -438,7 +438,7 @@ func TestReadRequest(t *testing.T) { // reqBytes treats req as a request (with \n delimiters) and returns it with \r\n delimiters, // ending in \r\n\r\n func reqBytes(req string) []byte { - return []byte(strings.Replace(strings.TrimSpace(req), "\n", "\r\n", -1) + "\r\n\r\n") + return []byte(strings.ReplaceAll(strings.TrimSpace(req), "\n", "\r\n") + "\r\n\r\n") } var badRequestTests = []struct { diff --git a/src/net/http/request.go b/src/net/http/request.go index a40b0a3cb8..967de7917f 100644 --- a/src/net/http/request.go +++ b/src/net/http/request.go @@ -105,7 +105,7 @@ var reqWriteExcludeHeader = map[string]bool{ // documentation for Request.Write and RoundTripper. type Request struct { // Method specifies the HTTP method (GET, POST, PUT, etc.). - // For client requests an empty string means GET. + // For client requests, an empty string means GET. // // Go's HTTP client does not support sending a request with // the CONNECT method. See the documentation on Transport for @@ -115,7 +115,7 @@ type Request struct { // URL specifies either the URI being requested (for server // requests) or the URL to access (for client requests). // - // For server requests the URL is parsed from the URI + // For server requests, the URL is parsed from the URI // supplied on the Request-Line as stored in RequestURI. For // most requests, fields other than Path and RawQuery will be // empty. (See RFC 7230, Section 5.3) @@ -128,7 +128,7 @@ type Request struct { // The protocol version for incoming server requests. // - // For client requests these fields are ignored. The HTTP + // For client requests, these fields are ignored. The HTTP // client code always uses either HTTP/1.1 or HTTP/2. // See the docs on Transport for details. Proto string // "HTTP/1.0" @@ -170,11 +170,11 @@ type Request struct { // Body is the request's body. // - // For client requests a nil body means the request has no + // For client requests, a nil body means the request has no // body, such as a GET request. The HTTP Client's Transport // is responsible for calling the Close method. // - // For server requests the Request Body is always non-nil + // For server requests, the Request Body is always non-nil // but will return EOF immediately when no body is present. // The Server will close the request body. The ServeHTTP // Handler does not need to. @@ -185,13 +185,14 @@ type Request struct { // reading the body more than once. Use of GetBody still // requires setting Body. // - // For server requests it is unused. + // For server requests, it is unused. GetBody func() (io.ReadCloser, error) // ContentLength records the length of the associated content. // The value -1 indicates that the length is unknown. // Values >= 0 indicate that the given number of bytes may // be read from Body. + // // For client requests, a value of 0 with a non-nil Body is // also treated as unknown. ContentLength int64 @@ -215,7 +216,7 @@ type Request struct { // Transport.DisableKeepAlives were set. Close bool - // For server requests Host specifies the host on which the URL + // For server requests, Host specifies the host on which the URL // is sought. Per RFC 7230, section 5.4, this is either the value // of the "Host" header or the host name given in the URL itself. // It may be of the form "host:port". For international domain @@ -228,7 +229,7 @@ type Request struct { // ServeMux supports patterns registered to particular host // names and thus protects its registered Handlers. // - // For client requests Host optionally overrides the Host + // For client requests, Host optionally overrides the Host // header to send. If empty, the Request.Write method uses // the value of URL.Host. Host may contain an international // domain name. @@ -255,14 +256,14 @@ type Request struct { // Trailer specifies additional headers that are sent after the request // body. // - // For server requests the Trailer map initially contains only the + // For server requests, the Trailer map initially contains only the // trailer keys, with nil values. (The client declares which trailers it // will later send.) While the handler is reading from Body, it must // not reference Trailer. After reading from Body returns EOF, Trailer // can be read again and will contain non-nil values, if they were sent // by the client. // - // For client requests Trailer must be initialized to a map containing + // For client requests, Trailer must be initialized to a map containing // the trailer keys to later send. The values may be nil or their final // values. The ContentLength must be 0 or -1, to send a chunked request. // After the HTTP request is sent the map values can be updated while @@ -1370,3 +1371,10 @@ func requestMethodUsuallyLacksBody(method string) bool { } return false } + +// requiresHTTP1 reports whether this request requires being sent on +// an HTTP/1 connection. +func (r *Request) requiresHTTP1() bool { + return hasToken(r.Header.Get("Connection"), "upgrade") && + strings.EqualFold(r.Header.Get("Upgrade"), "websocket") +} diff --git a/src/net/http/request_test.go b/src/net/http/request_test.go index 7a83ae5b1c..e8005571df 100644 --- a/src/net/http/request_test.go +++ b/src/net/http/request_test.go @@ -878,7 +878,7 @@ func testMissingFile(t *testing.T, req *Request) { } func newTestMultipartRequest(t *testing.T) *Request { - b := strings.NewReader(strings.Replace(message, "\n", "\r\n", -1)) + b := strings.NewReader(strings.ReplaceAll(message, "\n", "\r\n")) req, err := NewRequest("POST", "/", b) if err != nil { t.Fatal("NewRequest:", err) @@ -970,8 +970,8 @@ Content-Disposition: form-data; name="textb" ` func benchmarkReadRequest(b *testing.B, request string) { - request = request + "\n" // final \n - request = strings.Replace(request, "\n", "\r\n", -1) // expand \n to \r\n + request = request + "\n" // final \n + request = strings.ReplaceAll(request, "\n", "\r\n") // expand \n to \r\n b.SetBytes(int64(len(request))) r := bufio.NewReader(&infiniteReader{buf: []byte(request)}) b.ReportAllocs() diff --git a/src/net/http/roundtrip_js.go b/src/net/http/roundtrip_js.go index 16b7b891c8..38e4f5573e 100644 --- a/src/net/http/roundtrip_js.go +++ b/src/net/http/roundtrip_js.go @@ -116,7 +116,9 @@ func (t *Transport) RoundTrip(req *Request) (*Response, error) { b := result.Get("body") var body io.ReadCloser - if b != js.Undefined() { + // The body is undefined when the browser does not support streaming response bodies (Firefox), + // and null in certain error cases, i.e. when the request is blocked because of CORS settings. + if b != js.Undefined() && b != js.Null() { body = &streamReader{stream: b.Call("getReader")} } else { // Fall back to using ArrayBuffer diff --git a/src/net/http/serve_test.go b/src/net/http/serve_test.go index 8dae95678d..a282c4bc17 100644 --- a/src/net/http/serve_test.go +++ b/src/net/http/serve_test.go @@ -130,7 +130,7 @@ func (c *testConn) Close() error { // reqBytes treats req as a request (with \n delimiters) and returns it with \r\n delimiters, // ending in \r\n\r\n func reqBytes(req string) []byte { - return []byte(strings.Replace(strings.TrimSpace(req), "\n", "\r\n", -1) + "\r\n\r\n") + return []byte(strings.ReplaceAll(strings.TrimSpace(req), "\n", "\r\n") + "\r\n\r\n") } type handlerTest struct { @@ -4028,21 +4028,18 @@ func TestRequestBodyCloseDoesntBlock(t *testing.T) { } } -// test that ResponseWriter implements io.stringWriter. +// test that ResponseWriter implements io.StringWriter. func TestResponseWriterWriteString(t *testing.T) { okc := make(chan bool, 1) ht := newHandlerTest(HandlerFunc(func(w ResponseWriter, r *Request) { - type stringWriter interface { - WriteString(s string) (n int, err error) - } - _, ok := w.(stringWriter) + _, ok := w.(io.StringWriter) okc <- ok })) ht.rawResponse("GET / HTTP/1.0") select { case ok := <-okc: if !ok { - t.Error("ResponseWriter did not implement io.stringWriter") + t.Error("ResponseWriter did not implement io.StringWriter") } default: t.Error("handler was never called") diff --git a/src/net/http/server.go b/src/net/http/server.go index 449cfe5121..4227343fbe 100644 --- a/src/net/http/server.go +++ b/src/net/http/server.go @@ -1093,13 +1093,34 @@ func checkWriteHeaderCode(code int) { } } +// relevantCaller searches the call stack for the first function outside of net/http. +// The purpose of this function is to provide more helpful error messages. +func relevantCaller() runtime.Frame { + pc := make([]uintptr, 16) + n := runtime.Callers(1, pc) + frames := runtime.CallersFrames(pc[:n]) + var frame runtime.Frame + for { + frame, more := frames.Next() + if !strings.HasPrefix(frame.Function, "net/http.") { + return frame + } + if !more { + break + } + } + return frame +} + func (w *response) WriteHeader(code int) { if w.conn.hijacked() { - w.conn.server.logf("http: response.WriteHeader on hijacked connection") + caller := relevantCaller() + w.conn.server.logf("http: response.WriteHeader on hijacked connection from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line) return } if w.wroteHeader { - w.conn.server.logf("http: multiple response.WriteHeader calls") + caller := relevantCaller() + w.conn.server.logf("http: superfluous response.WriteHeader call from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line) return } checkWriteHeaderCode(code) @@ -1529,7 +1550,8 @@ func (w *response) WriteString(data string) (n int, err error) { func (w *response) write(lenData int, dataB []byte, dataS string) (n int, err error) { if w.conn.hijacked() { if lenData > 0 { - w.conn.server.logf("http: response.Write on hijacked connection") + caller := relevantCaller() + w.conn.server.logf("http: response.Write on hijacked connection from %s (%s:%d)", caller.Function, path.Base(caller.File), caller.Line) } return 0, ErrHijacked } diff --git a/src/net/http/transport.go b/src/net/http/transport.go index ffe4cdc0d6..b298ec6d7d 100644 --- a/src/net/http/transport.go +++ b/src/net/http/transport.go @@ -278,7 +278,7 @@ func (t *Transport) onceSetNextProtoDefaults() { // If they've already configured http2 with // golang.org/x/net/http2 instead of the bundled copy, try to - // get at its http2.Transport value (via the the "https" + // get at its http2.Transport value (via the "https" // altproto map) so we can call CloseIdleConnections on it if // requested. (Issue 22891) altProto, _ := t.altProto.Load().(map[string]RoundTripper) @@ -286,6 +286,7 @@ func (t *Transport) onceSetNextProtoDefaults() { if v := rv.Field(0); v.CanInterface() { if h2i, ok := v.Interface().(h2Transport); ok { t.h2transport = h2i + return } } } @@ -381,6 +382,19 @@ func (tr *transportRequest) setError(err error) { tr.mu.Unlock() } +// useRegisteredProtocol reports whether an alternate protocol (as reqistered +// with Transport.RegisterProtocol) should be respected for this request. +func (t *Transport) useRegisteredProtocol(req *Request) bool { + if req.URL.Scheme == "https" && req.requiresHTTP1() { + // If this request requires HTTP/1, don't use the + // "https" alternate protocol, which is used by the + // HTTP/2 code to take over requests if there's an + // existing cached HTTP/2 connection. + return false + } + return true +} + // roundTrip implements a RoundTripper over HTTP. func (t *Transport) roundTrip(req *Request) (*Response, error) { t.nextProtoOnce.Do(t.onceSetNextProtoDefaults) @@ -410,10 +424,12 @@ func (t *Transport) roundTrip(req *Request) (*Response, error) { } } - altProto, _ := t.altProto.Load().(map[string]RoundTripper) - if altRT := altProto[scheme]; altRT != nil { - if resp, err := altRT.RoundTrip(req); err != ErrSkipAltProtocol { - return resp, err + if t.useRegisteredProtocol(req) { + altProto, _ := t.altProto.Load().(map[string]RoundTripper) + if altRT := altProto[scheme]; altRT != nil { + if resp, err := altRT.RoundTrip(req); err != ErrSkipAltProtocol { + return resp, err + } } } if !isHTTP { @@ -477,9 +493,8 @@ func (t *Transport) roundTrip(req *Request) (*Response, error) { } testHookRoundTripRetried() - // Rewind the body if we're able to. (HTTP/2 does this itself so we only - // need to do it for HTTP/1.1 connections.) - if req.GetBody != nil && pconn.alt == nil { + // Rewind the body if we're able to. + if req.GetBody != nil { newReq := *req var err error newReq.Body, err = req.GetBody() @@ -653,6 +668,7 @@ func (t *Transport) connectMethodForRequest(treq *transportRequest) (cm connectM } } } + cm.onlyH1 = treq.requiresHTTP1() return cm, err } @@ -1155,6 +1171,9 @@ func (pconn *persistConn) addTLS(name string, trace *httptrace.ClientTrace) erro if cfg.ServerName == "" { cfg.ServerName = name } + if pconn.cacheKey.onlyH1 { + cfg.NextProtos = nil + } plainConn := pconn.conn tlsConn := tls.Client(plainConn, cfg) errc := make(chan error, 2) @@ -1361,10 +1380,11 @@ func (w persistConnWriter) Write(p []byte) (n int, err error) { // // A connect method may be of the following types: // -// Cache key form Description -// ----------------- ------------------------- +// connectMethod.key().String() Description +// ------------------------------ ------------------------- // |http|foo.com http directly to server, no proxy // |https|foo.com https directly to server, no proxy +// |https,h1|foo.com https directly to server w/o HTTP/2, no proxy // http://proxy.com|https|foo.com http to proxy, then CONNECT to foo.com // http://proxy.com|http http to proxy, http to anywhere after that // socks5://proxy.com|http|foo.com socks5 to proxy, then http to foo.com @@ -1379,6 +1399,7 @@ type connectMethod struct { // then targetAddr is not included in the connect method key, because the socket can // be reused for different targetAddr values. targetAddr string + onlyH1 bool // whether to disable HTTP/2 and force HTTP/1 } func (cm *connectMethod) key() connectMethodKey { @@ -1394,6 +1415,7 @@ func (cm *connectMethod) key() connectMethodKey { proxy: proxyStr, scheme: cm.targetScheme, addr: targetAddr, + onlyH1: cm.onlyH1, } } @@ -1428,11 +1450,16 @@ func (cm *connectMethod) tlsHost() string { // a URL. type connectMethodKey struct { proxy, scheme, addr string + onlyH1 bool } func (k connectMethodKey) String() string { // Only used by tests. - return fmt.Sprintf("%s|%s|%s", k.proxy, k.scheme, k.addr) + var h1 string + if k.onlyH1 { + h1 = ",h1" + } + return fmt.Sprintf("%s|%s%s|%s", k.proxy, k.scheme, h1, k.addr) } // persistConn wraps a connection, usually a persistent one diff --git a/src/net/http/transport_internal_test.go b/src/net/http/transport_internal_test.go index a5f29c97a9..92729e65b2 100644 --- a/src/net/http/transport_internal_test.go +++ b/src/net/http/transport_internal_test.go @@ -7,8 +7,13 @@ package http import ( + "bytes" + "crypto/tls" "errors" + "io" + "io/ioutil" "net" + "net/http/internal" "strings" "testing" ) @@ -178,3 +183,81 @@ func TestTransportShouldRetryRequest(t *testing.T) { } } } + +type roundTripFunc func(r *Request) (*Response, error) + +func (f roundTripFunc) RoundTrip(r *Request) (*Response, error) { + return f(r) +} + +// Issue 25009 +func TestTransportBodyAltRewind(t *testing.T) { + cert, err := tls.X509KeyPair(internal.LocalhostCert, internal.LocalhostKey) + if err != nil { + t.Fatal(err) + } + ln := newLocalListener(t) + defer ln.Close() + + go func() { + tln := tls.NewListener(ln, &tls.Config{ + NextProtos: []string{"foo"}, + Certificates: []tls.Certificate{cert}, + }) + for i := 0; i < 2; i++ { + sc, err := tln.Accept() + if err != nil { + t.Error(err) + return + } + if err := sc.(*tls.Conn).Handshake(); err != nil { + t.Error(err) + return + } + sc.Close() + } + }() + + addr := ln.Addr().String() + req, _ := NewRequest("POST", "https://example.org/", bytes.NewBufferString("request")) + roundTripped := false + tr := &Transport{ + DisableKeepAlives: true, + TLSNextProto: map[string]func(string, *tls.Conn) RoundTripper{ + "foo": func(authority string, c *tls.Conn) RoundTripper { + return roundTripFunc(func(r *Request) (*Response, error) { + n, _ := io.Copy(ioutil.Discard, r.Body) + if n == 0 { + t.Error("body length is zero") + } + if roundTripped { + return &Response{ + Body: NoBody, + StatusCode: 200, + }, nil + } + roundTripped = true + return nil, http2noCachedConnError{} + }) + }, + }, + DialTLS: func(_, _ string) (net.Conn, error) { + tc, err := tls.Dial("tcp", addr, &tls.Config{ + InsecureSkipVerify: true, + NextProtos: []string{"foo"}, + }) + if err != nil { + return nil, err + } + if err := tc.Handshake(); err != nil { + return nil, err + } + return tc, nil + }, + } + c := &Client{Transport: tr} + _, err = c.Do(req) + if err != nil { + t.Error(err) + } +} diff --git a/src/net/http/transport_test.go b/src/net/http/transport_test.go index 327b3b4996..739fe5f597 100644 --- a/src/net/http/transport_test.go +++ b/src/net/http/transport_test.go @@ -4753,7 +4753,7 @@ func TestClientTimeoutKillsConn_BeforeHeaders(t *testing.T) { } case <-time.After(timeout * 10): // If we didn't get into the Handler in 50ms, that probably means - // the builder was just slow and the the Get failed in that time + // the builder was just slow and the Get failed in that time // but never made it to the server. That's fine. We'll usually // test the part above on faster machines. t.Skip("skipping test on slow builder") @@ -4764,7 +4764,7 @@ func TestClientTimeoutKillsConn_BeforeHeaders(t *testing.T) { // conn is closed so that it's not reused. // // This is the test variant that has the server send response headers -// first, and time out during the the write of the response body. +// first, and time out during the write of the response body. func TestClientTimeoutKillsConn_AfterHeaders(t *testing.T) { setParallel(t) defer afterTest(t) diff --git a/src/net/lookup_unix.go b/src/net/lookup_unix.go index 04f443bb1a..1266680706 100644 --- a/src/net/lookup_unix.go +++ b/src/net/lookup_unix.go @@ -300,11 +300,21 @@ func (r *Resolver) lookupTXT(ctx context.Context, name string) ([]string, error) Server: server, } } + // Multiple strings in one TXT record need to be + // concatenated without separator to be consistent + // with previous Go resolver. + n := 0 + for _, s := range txt.TXT { + n += len(s) + } + txtJoin := make([]byte, 0, n) + for _, s := range txt.TXT { + txtJoin = append(txtJoin, s...) + } if len(txts) == 0 { - txts = txt.TXT - } else { - txts = append(txts, txt.TXT...) + txts = make([]string, 0, 1) } + txts = append(txts, string(txtJoin)) } return txts, nil } diff --git a/src/net/lookup_windows_test.go b/src/net/lookup_windows_test.go index cebb2d0558..d3748f28c3 100644 --- a/src/net/lookup_windows_test.go +++ b/src/net/lookup_windows_test.go @@ -150,7 +150,7 @@ func nslookup(qtype, name string) (string, error) { if err := cmd.Run(); err != nil { return "", err } - r := strings.Replace(out.String(), "\r\n", "\n", -1) + r := strings.ReplaceAll(out.String(), "\r\n", "\n") // nslookup stderr output contains also debug information such as // "Non-authoritative answer" and it doesn't return the correct errcode if strings.Contains(err.String(), "can't find") { diff --git a/src/net/mail/message_test.go b/src/net/mail/message_test.go index b19da52c42..14ac9192a4 100644 --- a/src/net/mail/message_test.go +++ b/src/net/mail/message_test.go @@ -668,9 +668,9 @@ func TestAddressParser(t *testing.T) { switch charset { case "iso-8859-15": - in = bytes.Replace(in, []byte("\xf6"), []byte("ö"), -1) + in = bytes.ReplaceAll(in, []byte("\xf6"), []byte("ö")) case "windows-1252": - in = bytes.Replace(in, []byte("\xe9"), []byte("é"), -1) + in = bytes.ReplaceAll(in, []byte("\xe9"), []byte("é")) } return bytes.NewReader(in), nil diff --git a/src/net/net_windows_test.go b/src/net/net_windows_test.go index 8dfd312980..8aa719f433 100644 --- a/src/net/net_windows_test.go +++ b/src/net/net_windows_test.go @@ -571,7 +571,7 @@ func TestInterfaceHardwareAddrWithGetmac(t *testing.T) { // skip these return } - addr = strings.Replace(addr, "-", ":", -1) + addr = strings.ReplaceAll(addr, "-", ":") cname := getValue("Connection Name") want[cname] = addr group = make(map[string]string) diff --git a/src/net/sendfile_test.go b/src/net/sendfile_test.go index 3b982774b0..f133744a66 100644 --- a/src/net/sendfile_test.go +++ b/src/net/sendfile_test.go @@ -17,9 +17,9 @@ import ( ) const ( - twain = "testdata/Mark.Twain-Tom.Sawyer.txt" - twainLen = 387851 - twainSHA256 = "461eb7cb2d57d293fc680c836464c9125e4382be3596f7d415093ae9db8fcb0e" + newton = "../testdata/Isaac.Newton-Opticks.txt" + newtonLen = 567198 + newtonSHA256 = "d4a9ac22462b35e7821a4f2706c211093da678620a8f9997989ee7cf8d507bbd" ) func TestSendfile(t *testing.T) { @@ -43,7 +43,7 @@ func TestSendfile(t *testing.T) { defer close(errc) defer conn.Close() - f, err := os.Open(twain) + f, err := os.Open(newton) if err != nil { errc <- err return @@ -58,8 +58,8 @@ func TestSendfile(t *testing.T) { return } - if sbytes != twainLen { - errc <- fmt.Errorf("sent %d bytes; expected %d", sbytes, twainLen) + if sbytes != newtonLen { + errc <- fmt.Errorf("sent %d bytes; expected %d", sbytes, newtonLen) return } }() @@ -79,11 +79,11 @@ func TestSendfile(t *testing.T) { t.Error(err) } - if rbytes != twainLen { - t.Errorf("received %d bytes; expected %d", rbytes, twainLen) + if rbytes != newtonLen { + t.Errorf("received %d bytes; expected %d", rbytes, newtonLen) } - if res := hex.EncodeToString(h.Sum(nil)); res != twainSHA256 { + if res := hex.EncodeToString(h.Sum(nil)); res != newtonSHA256 { t.Error("retrieved data hash did not match") } @@ -113,7 +113,7 @@ func TestSendfileParts(t *testing.T) { defer close(errc) defer conn.Close() - f, err := os.Open(twain) + f, err := os.Open(newton) if err != nil { errc <- err return @@ -174,7 +174,7 @@ func TestSendfileSeeked(t *testing.T) { defer close(errc) defer conn.Close() - f, err := os.Open(twain) + f, err := os.Open(newton) if err != nil { errc <- err return diff --git a/src/net/splice_linux.go b/src/net/splice_linux.go index 8a4d55af62..69c3f65770 100644 --- a/src/net/splice_linux.go +++ b/src/net/splice_linux.go @@ -11,7 +11,7 @@ import ( // splice transfers data from r to c using the splice system call to minimize // copies from and to userspace. c must be a TCP connection. Currently, splice -// is only enabled if r is a TCP or Unix connection. +// is only enabled if r is a TCP or a stream-oriented Unix connection. // // If splice returns handled == false, it has performed no work. func splice(c *netFD, r io.Reader) (written int64, err error, handled bool) { @@ -28,6 +28,9 @@ func splice(c *netFD, r io.Reader) (written int64, err error, handled bool) { if tc, ok := r.(*TCPConn); ok { s = tc.fd } else if uc, ok := r.(*UnixConn); ok { + if uc.fd.net != "unix" { + return 0, nil, false + } s = uc.fd } else { return 0, nil, false diff --git a/src/net/splice_test.go b/src/net/splice_test.go index 93e8b1f8cc..4c300172c5 100644 --- a/src/net/splice_test.go +++ b/src/net/splice_test.go @@ -24,6 +24,8 @@ func TestSplice(t *testing.T) { t.Skip("skipping unix-to-tcp tests") } t.Run("unix-to-tcp", func(t *testing.T) { testSplice(t, "unix", "tcp") }) + t.Run("no-unixpacket", testSpliceNoUnixpacket) + t.Run("no-unixgram", testSpliceNoUnixgram) } func testSplice(t *testing.T, upNet, downNet string) { @@ -208,6 +210,56 @@ func testSpliceIssue25985(t *testing.T, upNet, downNet string) { wg.Wait() } +func testSpliceNoUnixpacket(t *testing.T) { + clientUp, serverUp, err := spliceTestSocketPair("unixpacket") + if err != nil { + t.Fatal(err) + } + defer clientUp.Close() + defer serverUp.Close() + clientDown, serverDown, err := spliceTestSocketPair("tcp") + if err != nil { + t.Fatal(err) + } + defer clientDown.Close() + defer serverDown.Close() + // If splice called poll.Splice here, we'd get err == syscall.EINVAL + // and handled == false. If poll.Splice gets an EINVAL on the first + // try, it assumes the kernel it's running on doesn't support splice + // for unix sockets and returns handled == false. This works for our + // purposes by somewhat of an accident, but is not entirely correct. + // + // What we want is err == nil and handled == false, i.e. we never + // called poll.Splice, because we know the unix socket's network. + _, err, handled := splice(serverDown.(*TCPConn).fd, serverUp) + if err != nil || handled != false { + t.Fatalf("got err = %v, handled = %t, want nil error, handled == false", err, handled) + } +} + +func testSpliceNoUnixgram(t *testing.T) { + addr, err := ResolveUnixAddr("unixgram", testUnixAddr()) + if err != nil { + t.Fatal(err) + } + up, err := ListenUnixgram("unixgram", addr) + if err != nil { + t.Fatal(err) + } + defer up.Close() + clientDown, serverDown, err := spliceTestSocketPair("tcp") + if err != nil { + t.Fatal(err) + } + defer clientDown.Close() + defer serverDown.Close() + // Analogous to testSpliceNoUnixpacket. + _, err, handled := splice(serverDown.(*TCPConn).fd, up) + if err != nil || handled != false { + t.Fatalf("got err = %v, handled = %t, want nil error, handled == false", err, handled) + } +} + func BenchmarkSplice(b *testing.B) { testHookUninstaller.Do(uninstallTestHooks) diff --git a/src/net/testdata/Mark.Twain-Tom.Sawyer.txt b/src/net/testdata/Mark.Twain-Tom.Sawyer.txt deleted file mode 100644 index c9106fd522..0000000000 --- a/src/net/testdata/Mark.Twain-Tom.Sawyer.txt +++ /dev/null @@ -1,8465 +0,0 @@ -Produced by David Widger. The previous edition was updated by Jose -Menendez. - - - - - - THE ADVENTURES OF TOM SAWYER - BY - MARK TWAIN - (Samuel Langhorne Clemens) - - - - - P R E F A C E - -MOST of the adventures recorded in this book really occurred; one or -two were experiences of my own, the rest those of boys who were -schoolmates of mine. Huck Finn is drawn from life; Tom Sawyer also, but -not from an individual--he is a combination of the characteristics of -three boys whom I knew, and therefore belongs to the composite order of -architecture. - -The odd superstitions touched upon were all prevalent among children -and slaves in the West at the period of this story--that is to say, -thirty or forty years ago. - -Although my book is intended mainly for the entertainment of boys and -girls, I hope it will not be shunned by men and women on that account, -for part of my plan has been to try to pleasantly remind adults of what -they once were themselves, and of how they felt and thought and talked, -and what queer enterprises they sometimes engaged in. - - THE AUTHOR. - -HARTFORD, 1876. - - - - T O M S A W Y E R - - - -CHAPTER I - -"TOM!" - -No answer. - -"TOM!" - -No answer. - -"What's gone with that boy, I wonder? You TOM!" - -No answer. - -The old lady pulled her spectacles down and looked over them about the -room; then she put them up and looked out under them. She seldom or -never looked THROUGH them for so small a thing as a boy; they were her -state pair, the pride of her heart, and were built for "style," not -service--she could have seen through a pair of stove-lids just as well. -She looked perplexed for a moment, and then said, not fiercely, but -still loud enough for the furniture to hear: - -"Well, I lay if I get hold of you I'll--" - -She did not finish, for by this time she was bending down and punching -under the bed with the broom, and so she needed breath to punctuate the -punches with. She resurrected nothing but the cat. - -"I never did see the beat of that boy!" - -She went to the open door and stood in it and looked out among the -tomato vines and "jimpson" weeds that constituted the garden. No Tom. -So she lifted up her voice at an angle calculated for distance and -shouted: - -"Y-o-u-u TOM!" - -There was a slight noise behind her and she turned just in time to -seize a small boy by the slack of his roundabout and arrest his flight. - -"There! I might 'a' thought of that closet. What you been doing in -there?" - -"Nothing." - -"Nothing! Look at your hands. And look at your mouth. What IS that -truck?" - -"I don't know, aunt." - -"Well, I know. It's jam--that's what it is. Forty times I've said if -you didn't let that jam alone I'd skin you. Hand me that switch." - -The switch hovered in the air--the peril was desperate-- - -"My! Look behind you, aunt!" - -The old lady whirled round, and snatched her skirts out of danger. The -lad fled on the instant, scrambled up the high board-fence, and -disappeared over it. - -His aunt Polly stood surprised a moment, and then broke into a gentle -laugh. - -"Hang the boy, can't I never learn anything? Ain't he played me tricks -enough like that for me to be looking out for him by this time? But old -fools is the biggest fools there is. Can't learn an old dog new tricks, -as the saying is. But my goodness, he never plays them alike, two days, -and how is a body to know what's coming? He 'pears to know just how -long he can torment me before I get my dander up, and he knows if he -can make out to put me off for a minute or make me laugh, it's all down -again and I can't hit him a lick. I ain't doing my duty by that boy, -and that's the Lord's truth, goodness knows. Spare the rod and spile -the child, as the Good Book says. I'm a laying up sin and suffering for -us both, I know. He's full of the Old Scratch, but laws-a-me! he's my -own dead sister's boy, poor thing, and I ain't got the heart to lash -him, somehow. Every time I let him off, my conscience does hurt me so, -and every time I hit him my old heart most breaks. Well-a-well, man -that is born of woman is of few days and full of trouble, as the -Scripture says, and I reckon it's so. He'll play hookey this evening, * -and [* Southwestern for "afternoon"] I'll just be obleeged to make him -work, to-morrow, to punish him. It's mighty hard to make him work -Saturdays, when all the boys is having holiday, but he hates work more -than he hates anything else, and I've GOT to do some of my duty by him, -or I'll be the ruination of the child." - -Tom did play hookey, and he had a very good time. He got back home -barely in season to help Jim, the small colored boy, saw next-day's -wood and split the kindlings before supper--at least he was there in -time to tell his adventures to Jim while Jim did three-fourths of the -work. Tom's younger brother (or rather half-brother) Sid was already -through with his part of the work (picking up chips), for he was a -quiet boy, and had no adventurous, troublesome ways. - -While Tom was eating his supper, and stealing sugar as opportunity -offered, Aunt Polly asked him questions that were full of guile, and -very deep--for she wanted to trap him into damaging revealments. Like -many other simple-hearted souls, it was her pet vanity to believe she -was endowed with a talent for dark and mysterious diplomacy, and she -loved to contemplate her most transparent devices as marvels of low -cunning. Said she: - -"Tom, it was middling warm in school, warn't it?" - -"Yes'm." - -"Powerful warm, warn't it?" - -"Yes'm." - -"Didn't you want to go in a-swimming, Tom?" - -A bit of a scare shot through Tom--a touch of uncomfortable suspicion. -He searched Aunt Polly's face, but it told him nothing. So he said: - -"No'm--well, not very much." - -The old lady reached out her hand and felt Tom's shirt, and said: - -"But you ain't too warm now, though." And it flattered her to reflect -that she had discovered that the shirt was dry without anybody knowing -that that was what she had in her mind. But in spite of her, Tom knew -where the wind lay, now. So he forestalled what might be the next move: - -"Some of us pumped on our heads--mine's damp yet. See?" - -Aunt Polly was vexed to think she had overlooked that bit of -circumstantial evidence, and missed a trick. Then she had a new -inspiration: - -"Tom, you didn't have to undo your shirt collar where I sewed it, to -pump on your head, did you? Unbutton your jacket!" - -The trouble vanished out of Tom's face. He opened his jacket. His -shirt collar was securely sewed. - -"Bother! Well, go 'long with you. I'd made sure you'd played hookey -and been a-swimming. But I forgive ye, Tom. I reckon you're a kind of a -singed cat, as the saying is--better'n you look. THIS time." - -She was half sorry her sagacity had miscarried, and half glad that Tom -had stumbled into obedient conduct for once. - -But Sidney said: - -"Well, now, if I didn't think you sewed his collar with white thread, -but it's black." - -"Why, I did sew it with white! Tom!" - -But Tom did not wait for the rest. As he went out at the door he said: - -"Siddy, I'll lick you for that." - -In a safe place Tom examined two large needles which were thrust into -the lapels of his jacket, and had thread bound about them--one needle -carried white thread and the other black. He said: - -"She'd never noticed if it hadn't been for Sid. Confound it! sometimes -she sews it with white, and sometimes she sews it with black. I wish to -geeminy she'd stick to one or t'other--I can't keep the run of 'em. But -I bet you I'll lam Sid for that. I'll learn him!" - -He was not the Model Boy of the village. He knew the model boy very -well though--and loathed him. - -Within two minutes, or even less, he had forgotten all his troubles. -Not because his troubles were one whit less heavy and bitter to him -than a man's are to a man, but because a new and powerful interest bore -them down and drove them out of his mind for the time--just as men's -misfortunes are forgotten in the excitement of new enterprises. This -new interest was a valued novelty in whistling, which he had just -acquired from a negro, and he was suffering to practise it undisturbed. -It consisted in a peculiar bird-like turn, a sort of liquid warble, -produced by touching the tongue to the roof of the mouth at short -intervals in the midst of the music--the reader probably remembers how -to do it, if he has ever been a boy. Diligence and attention soon gave -him the knack of it, and he strode down the street with his mouth full -of harmony and his soul full of gratitude. He felt much as an -astronomer feels who has discovered a new planet--no doubt, as far as -strong, deep, unalloyed pleasure is concerned, the advantage was with -the boy, not the astronomer. - -The summer evenings were long. It was not dark, yet. Presently Tom -checked his whistle. A stranger was before him--a boy a shade larger -than himself. A new-comer of any age or either sex was an impressive -curiosity in the poor little shabby village of St. Petersburg. This boy -was well dressed, too--well dressed on a week-day. This was simply -astounding. His cap was a dainty thing, his close-buttoned blue cloth -roundabout was new and natty, and so were his pantaloons. He had shoes -on--and it was only Friday. He even wore a necktie, a bright bit of -ribbon. He had a citified air about him that ate into Tom's vitals. The -more Tom stared at the splendid marvel, the higher he turned up his -nose at his finery and the shabbier and shabbier his own outfit seemed -to him to grow. Neither boy spoke. If one moved, the other moved--but -only sidewise, in a circle; they kept face to face and eye to eye all -the time. Finally Tom said: - -"I can lick you!" - -"I'd like to see you try it." - -"Well, I can do it." - -"No you can't, either." - -"Yes I can." - -"No you can't." - -"I can." - -"You can't." - -"Can!" - -"Can't!" - -An uncomfortable pause. Then Tom said: - -"What's your name?" - -"'Tisn't any of your business, maybe." - -"Well I 'low I'll MAKE it my business." - -"Well why don't you?" - -"If you say much, I will." - -"Much--much--MUCH. There now." - -"Oh, you think you're mighty smart, DON'T you? I could lick you with -one hand tied behind me, if I wanted to." - -"Well why don't you DO it? You SAY you can do it." - -"Well I WILL, if you fool with me." - -"Oh yes--I've seen whole families in the same fix." - -"Smarty! You think you're SOME, now, DON'T you? Oh, what a hat!" - -"You can lump that hat if you don't like it. I dare you to knock it -off--and anybody that'll take a dare will suck eggs." - -"You're a liar!" - -"You're another." - -"You're a fighting liar and dasn't take it up." - -"Aw--take a walk!" - -"Say--if you give me much more of your sass I'll take and bounce a -rock off'n your head." - -"Oh, of COURSE you will." - -"Well I WILL." - -"Well why don't you DO it then? What do you keep SAYING you will for? -Why don't you DO it? It's because you're afraid." - -"I AIN'T afraid." - -"You are." - -"I ain't." - -"You are." - -Another pause, and more eying and sidling around each other. Presently -they were shoulder to shoulder. Tom said: - -"Get away from here!" - -"Go away yourself!" - -"I won't." - -"I won't either." - -So they stood, each with a foot placed at an angle as a brace, and -both shoving with might and main, and glowering at each other with -hate. But neither could get an advantage. After struggling till both -were hot and flushed, each relaxed his strain with watchful caution, -and Tom said: - -"You're a coward and a pup. I'll tell my big brother on you, and he -can thrash you with his little finger, and I'll make him do it, too." - -"What do I care for your big brother? I've got a brother that's bigger -than he is--and what's more, he can throw him over that fence, too." -[Both brothers were imaginary.] - -"That's a lie." - -"YOUR saying so don't make it so." - -Tom drew a line in the dust with his big toe, and said: - -"I dare you to step over that, and I'll lick you till you can't stand -up. Anybody that'll take a dare will steal sheep." - -The new boy stepped over promptly, and said: - -"Now you said you'd do it, now let's see you do it." - -"Don't you crowd me now; you better look out." - -"Well, you SAID you'd do it--why don't you do it?" - -"By jingo! for two cents I WILL do it." - -The new boy took two broad coppers out of his pocket and held them out -with derision. Tom struck them to the ground. In an instant both boys -were rolling and tumbling in the dirt, gripped together like cats; and -for the space of a minute they tugged and tore at each other's hair and -clothes, punched and scratched each other's nose, and covered -themselves with dust and glory. Presently the confusion took form, and -through the fog of battle Tom appeared, seated astride the new boy, and -pounding him with his fists. "Holler 'nuff!" said he. - -The boy only struggled to free himself. He was crying--mainly from rage. - -"Holler 'nuff!"--and the pounding went on. - -At last the stranger got out a smothered "'Nuff!" and Tom let him up -and said: - -"Now that'll learn you. Better look out who you're fooling with next -time." - -The new boy went off brushing the dust from his clothes, sobbing, -snuffling, and occasionally looking back and shaking his head and -threatening what he would do to Tom the "next time he caught him out." -To which Tom responded with jeers, and started off in high feather, and -as soon as his back was turned the new boy snatched up a stone, threw -it and hit him between the shoulders and then turned tail and ran like -an antelope. Tom chased the traitor home, and thus found out where he -lived. He then held a position at the gate for some time, daring the -enemy to come outside, but the enemy only made faces at him through the -window and declined. At last the enemy's mother appeared, and called -Tom a bad, vicious, vulgar child, and ordered him away. So he went -away; but he said he "'lowed" to "lay" for that boy. - -He got home pretty late that night, and when he climbed cautiously in -at the window, he uncovered an ambuscade, in the person of his aunt; -and when she saw the state his clothes were in her resolution to turn -his Saturday holiday into captivity at hard labor became adamantine in -its firmness. - - - -CHAPTER II - -SATURDAY morning was come, and all the summer world was bright and -fresh, and brimming with life. There was a song in every heart; and if -the heart was young the music issued at the lips. There was cheer in -every face and a spring in every step. The locust-trees were in bloom -and the fragrance of the blossoms filled the air. Cardiff Hill, beyond -the village and above it, was green with vegetation and it lay just far -enough away to seem a Delectable Land, dreamy, reposeful, and inviting. - -Tom appeared on the sidewalk with a bucket of whitewash and a -long-handled brush. He surveyed the fence, and all gladness left him and -a deep melancholy settled down upon his spirit. Thirty yards of board -fence nine feet high. Life to him seemed hollow, and existence but a -burden. Sighing, he dipped his brush and passed it along the topmost -plank; repeated the operation; did it again; compared the insignificant -whitewashed streak with the far-reaching continent of unwhitewashed -fence, and sat down on a tree-box discouraged. Jim came skipping out at -the gate with a tin pail, and singing Buffalo Gals. Bringing water from -the town pump had always been hateful work in Tom's eyes, before, but -now it did not strike him so. He remembered that there was company at -the pump. White, mulatto, and negro boys and girls were always there -waiting their turns, resting, trading playthings, quarrelling, -fighting, skylarking. And he remembered that although the pump was only -a hundred and fifty yards off, Jim never got back with a bucket of -water under an hour--and even then somebody generally had to go after -him. Tom said: - -"Say, Jim, I'll fetch the water if you'll whitewash some." - -Jim shook his head and said: - -"Can't, Mars Tom. Ole missis, she tole me I got to go an' git dis -water an' not stop foolin' roun' wid anybody. She say she spec' Mars -Tom gwine to ax me to whitewash, an' so she tole me go 'long an' 'tend -to my own business--she 'lowed SHE'D 'tend to de whitewashin'." - -"Oh, never you mind what she said, Jim. That's the way she always -talks. Gimme the bucket--I won't be gone only a a minute. SHE won't -ever know." - -"Oh, I dasn't, Mars Tom. Ole missis she'd take an' tar de head off'n -me. 'Deed she would." - -"SHE! She never licks anybody--whacks 'em over the head with her -thimble--and who cares for that, I'd like to know. She talks awful, but -talk don't hurt--anyways it don't if she don't cry. Jim, I'll give you -a marvel. I'll give you a white alley!" - -Jim began to waver. - -"White alley, Jim! And it's a bully taw." - -"My! Dat's a mighty gay marvel, I tell you! But Mars Tom I's powerful -'fraid ole missis--" - -"And besides, if you will I'll show you my sore toe." - -Jim was only human--this attraction was too much for him. He put down -his pail, took the white alley, and bent over the toe with absorbing -interest while the bandage was being unwound. In another moment he was -flying down the street with his pail and a tingling rear, Tom was -whitewashing with vigor, and Aunt Polly was retiring from the field -with a slipper in her hand and triumph in her eye. - -But Tom's energy did not last. He began to think of the fun he had -planned for this day, and his sorrows multiplied. Soon the free boys -would come tripping along on all sorts of delicious expeditions, and -they would make a world of fun of him for having to work--the very -thought of it burnt him like fire. He got out his worldly wealth and -examined it--bits of toys, marbles, and trash; enough to buy an -exchange of WORK, maybe, but not half enough to buy so much as half an -hour of pure freedom. So he returned his straitened means to his -pocket, and gave up the idea of trying to buy the boys. At this dark -and hopeless moment an inspiration burst upon him! Nothing less than a -great, magnificent inspiration. - -He took up his brush and went tranquilly to work. Ben Rogers hove in -sight presently--the very boy, of all boys, whose ridicule he had been -dreading. Ben's gait was the hop-skip-and-jump--proof enough that his -heart was light and his anticipations high. He was eating an apple, and -giving a long, melodious whoop, at intervals, followed by a deep-toned -ding-dong-dong, ding-dong-dong, for he was personating a steamboat. As -he drew near, he slackened speed, took the middle of the street, leaned -far over to starboard and rounded to ponderously and with laborious -pomp and circumstance--for he was personating the Big Missouri, and -considered himself to be drawing nine feet of water. He was boat and -captain and engine-bells combined, so he had to imagine himself -standing on his own hurricane-deck giving the orders and executing them: - -"Stop her, sir! Ting-a-ling-ling!" The headway ran almost out, and he -drew up slowly toward the sidewalk. - -"Ship up to back! Ting-a-ling-ling!" His arms straightened and -stiffened down his sides. - -"Set her back on the stabboard! Ting-a-ling-ling! Chow! ch-chow-wow! -Chow!" His right hand, meantime, describing stately circles--for it was -representing a forty-foot wheel. - -"Let her go back on the labboard! Ting-a-lingling! Chow-ch-chow-chow!" -The left hand began to describe circles. - -"Stop the stabboard! Ting-a-ling-ling! Stop the labboard! Come ahead -on the stabboard! Stop her! Let your outside turn over slow! -Ting-a-ling-ling! Chow-ow-ow! Get out that head-line! LIVELY now! -Come--out with your spring-line--what're you about there! Take a turn -round that stump with the bight of it! Stand by that stage, now--let her -go! Done with the engines, sir! Ting-a-ling-ling! SH'T! S'H'T! SH'T!" -(trying the gauge-cocks). - -Tom went on whitewashing--paid no attention to the steamboat. Ben -stared a moment and then said: "Hi-YI! YOU'RE up a stump, ain't you!" - -No answer. Tom surveyed his last touch with the eye of an artist, then -he gave his brush another gentle sweep and surveyed the result, as -before. Ben ranged up alongside of him. Tom's mouth watered for the -apple, but he stuck to his work. Ben said: - -"Hello, old chap, you got to work, hey?" - -Tom wheeled suddenly and said: - -"Why, it's you, Ben! I warn't noticing." - -"Say--I'm going in a-swimming, I am. Don't you wish you could? But of -course you'd druther WORK--wouldn't you? Course you would!" - -Tom contemplated the boy a bit, and said: - -"What do you call work?" - -"Why, ain't THAT work?" - -Tom resumed his whitewashing, and answered carelessly: - -"Well, maybe it is, and maybe it ain't. All I know, is, it suits Tom -Sawyer." - -"Oh come, now, you don't mean to let on that you LIKE it?" - -The brush continued to move. - -"Like it? Well, I don't see why I oughtn't to like it. Does a boy get -a chance to whitewash a fence every day?" - -That put the thing in a new light. Ben stopped nibbling his apple. Tom -swept his brush daintily back and forth--stepped back to note the -effect--added a touch here and there--criticised the effect again--Ben -watching every move and getting more and more interested, more and more -absorbed. Presently he said: - -"Say, Tom, let ME whitewash a little." - -Tom considered, was about to consent; but he altered his mind: - -"No--no--I reckon it wouldn't hardly do, Ben. You see, Aunt Polly's -awful particular about this fence--right here on the street, you know ---but if it was the back fence I wouldn't mind and SHE wouldn't. Yes, -she's awful particular about this fence; it's got to be done very -careful; I reckon there ain't one boy in a thousand, maybe two -thousand, that can do it the way it's got to be done." - -"No--is that so? Oh come, now--lemme just try. Only just a little--I'd -let YOU, if you was me, Tom." - -"Ben, I'd like to, honest injun; but Aunt Polly--well, Jim wanted to -do it, but she wouldn't let him; Sid wanted to do it, and she wouldn't -let Sid. Now don't you see how I'm fixed? If you was to tackle this -fence and anything was to happen to it--" - -"Oh, shucks, I'll be just as careful. Now lemme try. Say--I'll give -you the core of my apple." - -"Well, here--No, Ben, now don't. I'm afeard--" - -"I'll give you ALL of it!" - -Tom gave up the brush with reluctance in his face, but alacrity in his -heart. And while the late steamer Big Missouri worked and sweated in -the sun, the retired artist sat on a barrel in the shade close by, -dangled his legs, munched his apple, and planned the slaughter of more -innocents. There was no lack of material; boys happened along every -little while; they came to jeer, but remained to whitewash. By the time -Ben was fagged out, Tom had traded the next chance to Billy Fisher for -a kite, in good repair; and when he played out, Johnny Miller bought in -for a dead rat and a string to swing it with--and so on, and so on, -hour after hour. And when the middle of the afternoon came, from being -a poor poverty-stricken boy in the morning, Tom was literally rolling -in wealth. He had besides the things before mentioned, twelve marbles, -part of a jews-harp, a piece of blue bottle-glass to look through, a -spool cannon, a key that wouldn't unlock anything, a fragment of chalk, -a glass stopper of a decanter, a tin soldier, a couple of tadpoles, six -fire-crackers, a kitten with only one eye, a brass doorknob, a -dog-collar--but no dog--the handle of a knife, four pieces of -orange-peel, and a dilapidated old window sash. - -He had had a nice, good, idle time all the while--plenty of company ---and the fence had three coats of whitewash on it! If he hadn't run out -of whitewash he would have bankrupted every boy in the village. - -Tom said to himself that it was not such a hollow world, after all. He -had discovered a great law of human action, without knowing it--namely, -that in order to make a man or a boy covet a thing, it is only -necessary to make the thing difficult to attain. If he had been a great -and wise philosopher, like the writer of this book, he would now have -comprehended that Work consists of whatever a body is OBLIGED to do, -and that Play consists of whatever a body is not obliged to do. And -this would help him to understand why constructing artificial flowers -or performing on a tread-mill is work, while rolling ten-pins or -climbing Mont Blanc is only amusement. There are wealthy gentlemen in -England who drive four-horse passenger-coaches twenty or thirty miles -on a daily line, in the summer, because the privilege costs them -considerable money; but if they were offered wages for the service, -that would turn it into work and then they would resign. - -The boy mused awhile over the substantial change which had taken place -in his worldly circumstances, and then wended toward headquarters to -report. - - - -CHAPTER III - -TOM presented himself before Aunt Polly, who was sitting by an open -window in a pleasant rearward apartment, which was bedroom, -breakfast-room, dining-room, and library, combined. The balmy summer -air, the restful quiet, the odor of the flowers, and the drowsing murmur -of the bees had had their effect, and she was nodding over her knitting ---for she had no company but the cat, and it was asleep in her lap. Her -spectacles were propped up on her gray head for safety. She had thought -that of course Tom had deserted long ago, and she wondered at seeing him -place himself in her power again in this intrepid way. He said: "Mayn't -I go and play now, aunt?" - -"What, a'ready? How much have you done?" - -"It's all done, aunt." - -"Tom, don't lie to me--I can't bear it." - -"I ain't, aunt; it IS all done." - -Aunt Polly placed small trust in such evidence. She went out to see -for herself; and she would have been content to find twenty per cent. -of Tom's statement true. When she found the entire fence whitewashed, -and not only whitewashed but elaborately coated and recoated, and even -a streak added to the ground, her astonishment was almost unspeakable. -She said: - -"Well, I never! There's no getting round it, you can work when you're -a mind to, Tom." And then she diluted the compliment by adding, "But -it's powerful seldom you're a mind to, I'm bound to say. Well, go 'long -and play; but mind you get back some time in a week, or I'll tan you." - -She was so overcome by the splendor of his achievement that she took -him into the closet and selected a choice apple and delivered it to -him, along with an improving lecture upon the added value and flavor a -treat took to itself when it came without sin through virtuous effort. -And while she closed with a happy Scriptural flourish, he "hooked" a -doughnut. - -Then he skipped out, and saw Sid just starting up the outside stairway -that led to the back rooms on the second floor. Clods were handy and -the air was full of them in a twinkling. They raged around Sid like a -hail-storm; and before Aunt Polly could collect her surprised faculties -and sally to the rescue, six or seven clods had taken personal effect, -and Tom was over the fence and gone. There was a gate, but as a general -thing he was too crowded for time to make use of it. His soul was at -peace, now that he had settled with Sid for calling attention to his -black thread and getting him into trouble. - -Tom skirted the block, and came round into a muddy alley that led by -the back of his aunt's cow-stable. He presently got safely beyond the -reach of capture and punishment, and hastened toward the public square -of the village, where two "military" companies of boys had met for -conflict, according to previous appointment. Tom was General of one of -these armies, Joe Harper (a bosom friend) General of the other. These -two great commanders did not condescend to fight in person--that being -better suited to the still smaller fry--but sat together on an eminence -and conducted the field operations by orders delivered through -aides-de-camp. Tom's army won a great victory, after a long and -hard-fought battle. Then the dead were counted, prisoners exchanged, -the terms of the next disagreement agreed upon, and the day for the -necessary battle appointed; after which the armies fell into line and -marched away, and Tom turned homeward alone. - -As he was passing by the house where Jeff Thatcher lived, he saw a new -girl in the garden--a lovely little blue-eyed creature with yellow hair -plaited into two long-tails, white summer frock and embroidered -pantalettes. The fresh-crowned hero fell without firing a shot. A -certain Amy Lawrence vanished out of his heart and left not even a -memory of herself behind. He had thought he loved her to distraction; -he had regarded his passion as adoration; and behold it was only a poor -little evanescent partiality. He had been months winning her; she had -confessed hardly a week ago; he had been the happiest and the proudest -boy in the world only seven short days, and here in one instant of time -she had gone out of his heart like a casual stranger whose visit is -done. - -He worshipped this new angel with furtive eye, till he saw that she -had discovered him; then he pretended he did not know she was present, -and began to "show off" in all sorts of absurd boyish ways, in order to -win her admiration. He kept up this grotesque foolishness for some -time; but by-and-by, while he was in the midst of some dangerous -gymnastic performances, he glanced aside and saw that the little girl -was wending her way toward the house. Tom came up to the fence and -leaned on it, grieving, and hoping she would tarry yet awhile longer. -She halted a moment on the steps and then moved toward the door. Tom -heaved a great sigh as she put her foot on the threshold. But his face -lit up, right away, for she tossed a pansy over the fence a moment -before she disappeared. - -The boy ran around and stopped within a foot or two of the flower, and -then shaded his eyes with his hand and began to look down street as if -he had discovered something of interest going on in that direction. -Presently he picked up a straw and began trying to balance it on his -nose, with his head tilted far back; and as he moved from side to side, -in his efforts, he edged nearer and nearer toward the pansy; finally -his bare foot rested upon it, his pliant toes closed upon it, and he -hopped away with the treasure and disappeared round the corner. But -only for a minute--only while he could button the flower inside his -jacket, next his heart--or next his stomach, possibly, for he was not -much posted in anatomy, and not hypercritical, anyway. - -He returned, now, and hung about the fence till nightfall, "showing -off," as before; but the girl never exhibited herself again, though Tom -comforted himself a little with the hope that she had been near some -window, meantime, and been aware of his attentions. Finally he strode -home reluctantly, with his poor head full of visions. - -All through supper his spirits were so high that his aunt wondered -"what had got into the child." He took a good scolding about clodding -Sid, and did not seem to mind it in the least. He tried to steal sugar -under his aunt's very nose, and got his knuckles rapped for it. He said: - -"Aunt, you don't whack Sid when he takes it." - -"Well, Sid don't torment a body the way you do. You'd be always into -that sugar if I warn't watching you." - -Presently she stepped into the kitchen, and Sid, happy in his -immunity, reached for the sugar-bowl--a sort of glorying over Tom which -was wellnigh unbearable. But Sid's fingers slipped and the bowl dropped -and broke. Tom was in ecstasies. In such ecstasies that he even -controlled his tongue and was silent. He said to himself that he would -not speak a word, even when his aunt came in, but would sit perfectly -still till she asked who did the mischief; and then he would tell, and -there would be nothing so good in the world as to see that pet model -"catch it." He was so brimful of exultation that he could hardly hold -himself when the old lady came back and stood above the wreck -discharging lightnings of wrath from over her spectacles. He said to -himself, "Now it's coming!" And the next instant he was sprawling on -the floor! The potent palm was uplifted to strike again when Tom cried -out: - -"Hold on, now, what 'er you belting ME for?--Sid broke it!" - -Aunt Polly paused, perplexed, and Tom looked for healing pity. But -when she got her tongue again, she only said: - -"Umf! Well, you didn't get a lick amiss, I reckon. You been into some -other audacious mischief when I wasn't around, like enough." - -Then her conscience reproached her, and she yearned to say something -kind and loving; but she judged that this would be construed into a -confession that she had been in the wrong, and discipline forbade that. -So she kept silence, and went about her affairs with a troubled heart. -Tom sulked in a corner and exalted his woes. He knew that in her heart -his aunt was on her knees to him, and he was morosely gratified by the -consciousness of it. He would hang out no signals, he would take notice -of none. He knew that a yearning glance fell upon him, now and then, -through a film of tears, but he refused recognition of it. He pictured -himself lying sick unto death and his aunt bending over him beseeching -one little forgiving word, but he would turn his face to the wall, and -die with that word unsaid. Ah, how would she feel then? And he pictured -himself brought home from the river, dead, with his curls all wet, and -his sore heart at rest. How she would throw herself upon him, and how -her tears would fall like rain, and her lips pray God to give her back -her boy and she would never, never abuse him any more! But he would lie -there cold and white and make no sign--a poor little sufferer, whose -griefs were at an end. He so worked upon his feelings with the pathos -of these dreams, that he had to keep swallowing, he was so like to -choke; and his eyes swam in a blur of water, which overflowed when he -winked, and ran down and trickled from the end of his nose. And such a -luxury to him was this petting of his sorrows, that he could not bear -to have any worldly cheeriness or any grating delight intrude upon it; -it was too sacred for such contact; and so, presently, when his cousin -Mary danced in, all alive with the joy of seeing home again after an -age-long visit of one week to the country, he got up and moved in -clouds and darkness out at one door as she brought song and sunshine in -at the other. - -He wandered far from the accustomed haunts of boys, and sought -desolate places that were in harmony with his spirit. A log raft in the -river invited him, and he seated himself on its outer edge and -contemplated the dreary vastness of the stream, wishing, the while, -that he could only be drowned, all at once and unconsciously, without -undergoing the uncomfortable routine devised by nature. Then he thought -of his flower. He got it out, rumpled and wilted, and it mightily -increased his dismal felicity. He wondered if she would pity him if she -knew? Would she cry, and wish that she had a right to put her arms -around his neck and comfort him? Or would she turn coldly away like all -the hollow world? This picture brought such an agony of pleasurable -suffering that he worked it over and over again in his mind and set it -up in new and varied lights, till he wore it threadbare. At last he -rose up sighing and departed in the darkness. - -About half-past nine or ten o'clock he came along the deserted street -to where the Adored Unknown lived; he paused a moment; no sound fell -upon his listening ear; a candle was casting a dull glow upon the -curtain of a second-story window. Was the sacred presence there? He -climbed the fence, threaded his stealthy way through the plants, till -he stood under that window; he looked up at it long, and with emotion; -then he laid him down on the ground under it, disposing himself upon -his back, with his hands clasped upon his breast and holding his poor -wilted flower. And thus he would die--out in the cold world, with no -shelter over his homeless head, no friendly hand to wipe the -death-damps from his brow, no loving face to bend pityingly over him -when the great agony came. And thus SHE would see him when she looked -out upon the glad morning, and oh! would she drop one little tear upon -his poor, lifeless form, would she heave one little sigh to see a bright -young life so rudely blighted, so untimely cut down? - -The window went up, a maid-servant's discordant voice profaned the -holy calm, and a deluge of water drenched the prone martyr's remains! - -The strangling hero sprang up with a relieving snort. There was a whiz -as of a missile in the air, mingled with the murmur of a curse, a sound -as of shivering glass followed, and a small, vague form went over the -fence and shot away in the gloom. - -Not long after, as Tom, all undressed for bed, was surveying his -drenched garments by the light of a tallow dip, Sid woke up; but if he -had any dim idea of making any "references to allusions," he thought -better of it and held his peace, for there was danger in Tom's eye. - -Tom turned in without the added vexation of prayers, and Sid made -mental note of the omission. - - - -CHAPTER IV - -THE sun rose upon a tranquil world, and beamed down upon the peaceful -village like a benediction. Breakfast over, Aunt Polly had family -worship: it began with a prayer built from the ground up of solid -courses of Scriptural quotations, welded together with a thin mortar of -originality; and from the summit of this she delivered a grim chapter -of the Mosaic Law, as from Sinai. - -Then Tom girded up his loins, so to speak, and went to work to "get -his verses." Sid had learned his lesson days before. Tom bent all his -energies to the memorizing of five verses, and he chose part of the -Sermon on the Mount, because he could find no verses that were shorter. -At the end of half an hour Tom had a vague general idea of his lesson, -but no more, for his mind was traversing the whole field of human -thought, and his hands were busy with distracting recreations. Mary -took his book to hear him recite, and he tried to find his way through -the fog: - -"Blessed are the--a--a--" - -"Poor"-- - -"Yes--poor; blessed are the poor--a--a--" - -"In spirit--" - -"In spirit; blessed are the poor in spirit, for they--they--" - -"THEIRS--" - -"For THEIRS. Blessed are the poor in spirit, for theirs is the kingdom -of heaven. Blessed are they that mourn, for they--they--" - -"Sh--" - -"For they--a--" - -"S, H, A--" - -"For they S, H--Oh, I don't know what it is!" - -"SHALL!" - -"Oh, SHALL! for they shall--for they shall--a--a--shall mourn--a--a-- -blessed are they that shall--they that--a--they that shall mourn, for -they shall--a--shall WHAT? Why don't you tell me, Mary?--what do you -want to be so mean for?" - -"Oh, Tom, you poor thick-headed thing, I'm not teasing you. I wouldn't -do that. You must go and learn it again. Don't you be discouraged, Tom, -you'll manage it--and if you do, I'll give you something ever so nice. -There, now, that's a good boy." - -"All right! What is it, Mary, tell me what it is." - -"Never you mind, Tom. You know if I say it's nice, it is nice." - -"You bet you that's so, Mary. All right, I'll tackle it again." - -And he did "tackle it again"--and under the double pressure of -curiosity and prospective gain he did it with such spirit that he -accomplished a shining success. Mary gave him a brand-new "Barlow" -knife worth twelve and a half cents; and the convulsion of delight that -swept his system shook him to his foundations. True, the knife would -not cut anything, but it was a "sure-enough" Barlow, and there was -inconceivable grandeur in that--though where the Western boys ever got -the idea that such a weapon could possibly be counterfeited to its -injury is an imposing mystery and will always remain so, perhaps. Tom -contrived to scarify the cupboard with it, and was arranging to begin -on the bureau, when he was called off to dress for Sunday-school. - -Mary gave him a tin basin of water and a piece of soap, and he went -outside the door and set the basin on a little bench there; then he -dipped the soap in the water and laid it down; turned up his sleeves; -poured out the water on the ground, gently, and then entered the -kitchen and began to wipe his face diligently on the towel behind the -door. But Mary removed the towel and said: - -"Now ain't you ashamed, Tom. You mustn't be so bad. Water won't hurt -you." - -Tom was a trifle disconcerted. The basin was refilled, and this time -he stood over it a little while, gathering resolution; took in a big -breath and began. When he entered the kitchen presently, with both eyes -shut and groping for the towel with his hands, an honorable testimony -of suds and water was dripping from his face. But when he emerged from -the towel, he was not yet satisfactory, for the clean territory stopped -short at his chin and his jaws, like a mask; below and beyond this line -there was a dark expanse of unirrigated soil that spread downward in -front and backward around his neck. Mary took him in hand, and when she -was done with him he was a man and a brother, without distinction of -color, and his saturated hair was neatly brushed, and its short curls -wrought into a dainty and symmetrical general effect. [He privately -smoothed out the curls, with labor and difficulty, and plastered his -hair close down to his head; for he held curls to be effeminate, and -his own filled his life with bitterness.] Then Mary got out a suit of -his clothing that had been used only on Sundays during two years--they -were simply called his "other clothes"--and so by that we know the -size of his wardrobe. The girl "put him to rights" after he had dressed -himself; she buttoned his neat roundabout up to his chin, turned his -vast shirt collar down over his shoulders, brushed him off and crowned -him with his speckled straw hat. He now looked exceedingly improved and -uncomfortable. He was fully as uncomfortable as he looked; for there -was a restraint about whole clothes and cleanliness that galled him. He -hoped that Mary would forget his shoes, but the hope was blighted; she -coated them thoroughly with tallow, as was the custom, and brought them -out. He lost his temper and said he was always being made to do -everything he didn't want to do. But Mary said, persuasively: - -"Please, Tom--that's a good boy." - -So he got into the shoes snarling. Mary was soon ready, and the three -children set out for Sunday-school--a place that Tom hated with his -whole heart; but Sid and Mary were fond of it. - -Sabbath-school hours were from nine to half-past ten; and then church -service. Two of the children always remained for the sermon -voluntarily, and the other always remained too--for stronger reasons. -The church's high-backed, uncushioned pews would seat about three -hundred persons; the edifice was but a small, plain affair, with a sort -of pine board tree-box on top of it for a steeple. At the door Tom -dropped back a step and accosted a Sunday-dressed comrade: - -"Say, Billy, got a yaller ticket?" - -"Yes." - -"What'll you take for her?" - -"What'll you give?" - -"Piece of lickrish and a fish-hook." - -"Less see 'em." - -Tom exhibited. They were satisfactory, and the property changed hands. -Then Tom traded a couple of white alleys for three red tickets, and -some small trifle or other for a couple of blue ones. He waylaid other -boys as they came, and went on buying tickets of various colors ten or -fifteen minutes longer. He entered the church, now, with a swarm of -clean and noisy boys and girls, proceeded to his seat and started a -quarrel with the first boy that came handy. The teacher, a grave, -elderly man, interfered; then turned his back a moment and Tom pulled a -boy's hair in the next bench, and was absorbed in his book when the boy -turned around; stuck a pin in another boy, presently, in order to hear -him say "Ouch!" and got a new reprimand from his teacher. Tom's whole -class were of a pattern--restless, noisy, and troublesome. When they -came to recite their lessons, not one of them knew his verses -perfectly, but had to be prompted all along. However, they worried -through, and each got his reward--in small blue tickets, each with a -passage of Scripture on it; each blue ticket was pay for two verses of -the recitation. Ten blue tickets equalled a red one, and could be -exchanged for it; ten red tickets equalled a yellow one; for ten yellow -tickets the superintendent gave a very plainly bound Bible (worth forty -cents in those easy times) to the pupil. How many of my readers would -have the industry and application to memorize two thousand verses, even -for a Dore Bible? And yet Mary had acquired two Bibles in this way--it -was the patient work of two years--and a boy of German parentage had -won four or five. He once recited three thousand verses without -stopping; but the strain upon his mental faculties was too great, and -he was little better than an idiot from that day forth--a grievous -misfortune for the school, for on great occasions, before company, the -superintendent (as Tom expressed it) had always made this boy come out -and "spread himself." Only the older pupils managed to keep their -tickets and stick to their tedious work long enough to get a Bible, and -so the delivery of one of these prizes was a rare and noteworthy -circumstance; the successful pupil was so great and conspicuous for -that day that on the spot every scholar's heart was fired with a fresh -ambition that often lasted a couple of weeks. It is possible that Tom's -mental stomach had never really hungered for one of those prizes, but -unquestionably his entire being had for many a day longed for the glory -and the eclat that came with it. - -In due course the superintendent stood up in front of the pulpit, with -a closed hymn-book in his hand and his forefinger inserted between its -leaves, and commanded attention. When a Sunday-school superintendent -makes his customary little speech, a hymn-book in the hand is as -necessary as is the inevitable sheet of music in the hand of a singer -who stands forward on the platform and sings a solo at a concert ---though why, is a mystery: for neither the hymn-book nor the sheet of -music is ever referred to by the sufferer. This superintendent was a -slim creature of thirty-five, with a sandy goatee and short sandy hair; -he wore a stiff standing-collar whose upper edge almost reached his -ears and whose sharp points curved forward abreast the corners of his -mouth--a fence that compelled a straight lookout ahead, and a turning -of the whole body when a side view was required; his chin was propped -on a spreading cravat which was as broad and as long as a bank-note, -and had fringed ends; his boot toes were turned sharply up, in the -fashion of the day, like sleigh-runners--an effect patiently and -laboriously produced by the young men by sitting with their toes -pressed against a wall for hours together. Mr. Walters was very earnest -of mien, and very sincere and honest at heart; and he held sacred -things and places in such reverence, and so separated them from worldly -matters, that unconsciously to himself his Sunday-school voice had -acquired a peculiar intonation which was wholly absent on week-days. He -began after this fashion: - -"Now, children, I want you all to sit up just as straight and pretty -as you can and give me all your attention for a minute or two. There ---that is it. That is the way good little boys and girls should do. I see -one little girl who is looking out of the window--I am afraid she -thinks I am out there somewhere--perhaps up in one of the trees making -a speech to the little birds. [Applausive titter.] I want to tell you -how good it makes me feel to see so many bright, clean little faces -assembled in a place like this, learning to do right and be good." And -so forth and so on. It is not necessary to set down the rest of the -oration. It was of a pattern which does not vary, and so it is familiar -to us all. - -The latter third of the speech was marred by the resumption of fights -and other recreations among certain of the bad boys, and by fidgetings -and whisperings that extended far and wide, washing even to the bases -of isolated and incorruptible rocks like Sid and Mary. But now every -sound ceased suddenly, with the subsidence of Mr. Walters' voice, and -the conclusion of the speech was received with a burst of silent -gratitude. - -A good part of the whispering had been occasioned by an event which -was more or less rare--the entrance of visitors: lawyer Thatcher, -accompanied by a very feeble and aged man; a fine, portly, middle-aged -gentleman with iron-gray hair; and a dignified lady who was doubtless -the latter's wife. The lady was leading a child. Tom had been restless -and full of chafings and repinings; conscience-smitten, too--he could -not meet Amy Lawrence's eye, he could not brook her loving gaze. But -when he saw this small new-comer his soul was all ablaze with bliss in -a moment. The next moment he was "showing off" with all his might ---cuffing boys, pulling hair, making faces--in a word, using every art -that seemed likely to fascinate a girl and win her applause. His -exaltation had but one alloy--the memory of his humiliation in this -angel's garden--and that record in sand was fast washing out, under -the waves of happiness that were sweeping over it now. - -The visitors were given the highest seat of honor, and as soon as Mr. -Walters' speech was finished, he introduced them to the school. The -middle-aged man turned out to be a prodigious personage--no less a one -than the county judge--altogether the most august creation these -children had ever looked upon--and they wondered what kind of material -he was made of--and they half wanted to hear him roar, and were half -afraid he might, too. He was from Constantinople, twelve miles away--so -he had travelled, and seen the world--these very eyes had looked upon -the county court-house--which was said to have a tin roof. The awe -which these reflections inspired was attested by the impressive silence -and the ranks of staring eyes. This was the great Judge Thatcher, -brother of their own lawyer. Jeff Thatcher immediately went forward, to -be familiar with the great man and be envied by the school. It would -have been music to his soul to hear the whisperings: - -"Look at him, Jim! He's a going up there. Say--look! he's a going to -shake hands with him--he IS shaking hands with him! By jings, don't you -wish you was Jeff?" - -Mr. Walters fell to "showing off," with all sorts of official -bustlings and activities, giving orders, delivering judgments, -discharging directions here, there, everywhere that he could find a -target. The librarian "showed off"--running hither and thither with his -arms full of books and making a deal of the splutter and fuss that -insect authority delights in. The young lady teachers "showed off" ---bending sweetly over pupils that were lately being boxed, lifting -pretty warning fingers at bad little boys and patting good ones -lovingly. The young gentlemen teachers "showed off" with small -scoldings and other little displays of authority and fine attention to -discipline--and most of the teachers, of both sexes, found business up -at the library, by the pulpit; and it was business that frequently had -to be done over again two or three times (with much seeming vexation). -The little girls "showed off" in various ways, and the little boys -"showed off" with such diligence that the air was thick with paper wads -and the murmur of scufflings. And above it all the great man sat and -beamed a majestic judicial smile upon all the house, and warmed himself -in the sun of his own grandeur--for he was "showing off," too. - -There was only one thing wanting to make Mr. Walters' ecstasy -complete, and that was a chance to deliver a Bible-prize and exhibit a -prodigy. Several pupils had a few yellow tickets, but none had enough ---he had been around among the star pupils inquiring. He would have given -worlds, now, to have that German lad back again with a sound mind. - -And now at this moment, when hope was dead, Tom Sawyer came forward -with nine yellow tickets, nine red tickets, and ten blue ones, and -demanded a Bible. This was a thunderbolt out of a clear sky. Walters -was not expecting an application from this source for the next ten -years. But there was no getting around it--here were the certified -checks, and they were good for their face. Tom was therefore elevated -to a place with the Judge and the other elect, and the great news was -announced from headquarters. It was the most stunning surprise of the -decade, and so profound was the sensation that it lifted the new hero -up to the judicial one's altitude, and the school had two marvels to -gaze upon in place of one. The boys were all eaten up with envy--but -those that suffered the bitterest pangs were those who perceived too -late that they themselves had contributed to this hated splendor by -trading tickets to Tom for the wealth he had amassed in selling -whitewashing privileges. These despised themselves, as being the dupes -of a wily fraud, a guileful snake in the grass. - -The prize was delivered to Tom with as much effusion as the -superintendent could pump up under the circumstances; but it lacked -somewhat of the true gush, for the poor fellow's instinct taught him -that there was a mystery here that could not well bear the light, -perhaps; it was simply preposterous that this boy had warehoused two -thousand sheaves of Scriptural wisdom on his premises--a dozen would -strain his capacity, without a doubt. - -Amy Lawrence was proud and glad, and she tried to make Tom see it in -her face--but he wouldn't look. She wondered; then she was just a grain -troubled; next a dim suspicion came and went--came again; she watched; -a furtive glance told her worlds--and then her heart broke, and she was -jealous, and angry, and the tears came and she hated everybody. Tom -most of all (she thought). - -Tom was introduced to the Judge; but his tongue was tied, his breath -would hardly come, his heart quaked--partly because of the awful -greatness of the man, but mainly because he was her parent. He would -have liked to fall down and worship him, if it were in the dark. The -Judge put his hand on Tom's head and called him a fine little man, and -asked him what his name was. The boy stammered, gasped, and got it out: - -"Tom." - -"Oh, no, not Tom--it is--" - -"Thomas." - -"Ah, that's it. I thought there was more to it, maybe. That's very -well. But you've another one I daresay, and you'll tell it to me, won't -you?" - -"Tell the gentleman your other name, Thomas," said Walters, "and say -sir. You mustn't forget your manners." - -"Thomas Sawyer--sir." - -"That's it! That's a good boy. Fine boy. Fine, manly little fellow. -Two thousand verses is a great many--very, very great many. And you -never can be sorry for the trouble you took to learn them; for -knowledge is worth more than anything there is in the world; it's what -makes great men and good men; you'll be a great man and a good man -yourself, some day, Thomas, and then you'll look back and say, It's all -owing to the precious Sunday-school privileges of my boyhood--it's all -owing to my dear teachers that taught me to learn--it's all owing to -the good superintendent, who encouraged me, and watched over me, and -gave me a beautiful Bible--a splendid elegant Bible--to keep and have -it all for my own, always--it's all owing to right bringing up! That is -what you will say, Thomas--and you wouldn't take any money for those -two thousand verses--no indeed you wouldn't. And now you wouldn't mind -telling me and this lady some of the things you've learned--no, I know -you wouldn't--for we are proud of little boys that learn. Now, no -doubt you know the names of all the twelve disciples. Won't you tell us -the names of the first two that were appointed?" - -Tom was tugging at a button-hole and looking sheepish. He blushed, -now, and his eyes fell. Mr. Walters' heart sank within him. He said to -himself, it is not possible that the boy can answer the simplest -question--why DID the Judge ask him? Yet he felt obliged to speak up -and say: - -"Answer the gentleman, Thomas--don't be afraid." - -Tom still hung fire. - -"Now I know you'll tell me," said the lady. "The names of the first -two disciples were--" - -"DAVID AND GOLIAH!" - -Let us draw the curtain of charity over the rest of the scene. - - - -CHAPTER V - -ABOUT half-past ten the cracked bell of the small church began to -ring, and presently the people began to gather for the morning sermon. -The Sunday-school children distributed themselves about the house and -occupied pews with their parents, so as to be under supervision. Aunt -Polly came, and Tom and Sid and Mary sat with her--Tom being placed -next the aisle, in order that he might be as far away from the open -window and the seductive outside summer scenes as possible. The crowd -filed up the aisles: the aged and needy postmaster, who had seen better -days; the mayor and his wife--for they had a mayor there, among other -unnecessaries; the justice of the peace; the widow Douglass, fair, -smart, and forty, a generous, good-hearted soul and well-to-do, her -hill mansion the only palace in the town, and the most hospitable and -much the most lavish in the matter of festivities that St. Petersburg -could boast; the bent and venerable Major and Mrs. Ward; lawyer -Riverson, the new notable from a distance; next the belle of the -village, followed by a troop of lawn-clad and ribbon-decked young -heart-breakers; then all the young clerks in town in a body--for they -had stood in the vestibule sucking their cane-heads, a circling wall of -oiled and simpering admirers, till the last girl had run their gantlet; -and last of all came the Model Boy, Willie Mufferson, taking as heedful -care of his mother as if she were cut glass. He always brought his -mother to church, and was the pride of all the matrons. The boys all -hated him, he was so good. And besides, he had been "thrown up to them" -so much. His white handkerchief was hanging out of his pocket behind, as -usual on Sundays--accidentally. Tom had no handkerchief, and he looked -upon boys who had as snobs. - -The congregation being fully assembled, now, the bell rang once more, -to warn laggards and stragglers, and then a solemn hush fell upon the -church which was only broken by the tittering and whispering of the -choir in the gallery. The choir always tittered and whispered all -through service. There was once a church choir that was not ill-bred, -but I have forgotten where it was, now. It was a great many years ago, -and I can scarcely remember anything about it, but I think it was in -some foreign country. - -The minister gave out the hymn, and read it through with a relish, in -a peculiar style which was much admired in that part of the country. -His voice began on a medium key and climbed steadily up till it reached -a certain point, where it bore with strong emphasis upon the topmost -word and then plunged down as if from a spring-board: - - Shall I be car-ri-ed toe the skies, on flow'ry BEDS of ease, - - Whilst others fight to win the prize, and sail thro' BLOODY seas? - -He was regarded as a wonderful reader. At church "sociables" he was -always called upon to read poetry; and when he was through, the ladies -would lift up their hands and let them fall helplessly in their laps, -and "wall" their eyes, and shake their heads, as much as to say, "Words -cannot express it; it is too beautiful, TOO beautiful for this mortal -earth." - -After the hymn had been sung, the Rev. Mr. Sprague turned himself into -a bulletin-board, and read off "notices" of meetings and societies and -things till it seemed that the list would stretch out to the crack of -doom--a queer custom which is still kept up in America, even in cities, -away here in this age of abundant newspapers. Often, the less there is -to justify a traditional custom, the harder it is to get rid of it. - -And now the minister prayed. A good, generous prayer it was, and went -into details: it pleaded for the church, and the little children of the -church; for the other churches of the village; for the village itself; -for the county; for the State; for the State officers; for the United -States; for the churches of the United States; for Congress; for the -President; for the officers of the Government; for poor sailors, tossed -by stormy seas; for the oppressed millions groaning under the heel of -European monarchies and Oriental despotisms; for such as have the light -and the good tidings, and yet have not eyes to see nor ears to hear -withal; for the heathen in the far islands of the sea; and closed with -a supplication that the words he was about to speak might find grace -and favor, and be as seed sown in fertile ground, yielding in time a -grateful harvest of good. Amen. - -There was a rustling of dresses, and the standing congregation sat -down. The boy whose history this book relates did not enjoy the prayer, -he only endured it--if he even did that much. He was restive all -through it; he kept tally of the details of the prayer, unconsciously ---for he was not listening, but he knew the ground of old, and the -clergyman's regular route over it--and when a little trifle of new -matter was interlarded, his ear detected it and his whole nature -resented it; he considered additions unfair, and scoundrelly. In the -midst of the prayer a fly had lit on the back of the pew in front of -him and tortured his spirit by calmly rubbing its hands together, -embracing its head with its arms, and polishing it so vigorously that -it seemed to almost part company with the body, and the slender thread -of a neck was exposed to view; scraping its wings with its hind legs -and smoothing them to its body as if they had been coat-tails; going -through its whole toilet as tranquilly as if it knew it was perfectly -safe. As indeed it was; for as sorely as Tom's hands itched to grab for -it they did not dare--he believed his soul would be instantly destroyed -if he did such a thing while the prayer was going on. But with the -closing sentence his hand began to curve and steal forward; and the -instant the "Amen" was out the fly was a prisoner of war. His aunt -detected the act and made him let it go. - -The minister gave out his text and droned along monotonously through -an argument that was so prosy that many a head by and by began to nod ---and yet it was an argument that dealt in limitless fire and brimstone -and thinned the predestined elect down to a company so small as to be -hardly worth the saving. Tom counted the pages of the sermon; after -church he always knew how many pages there had been, but he seldom knew -anything else about the discourse. However, this time he was really -interested for a little while. The minister made a grand and moving -picture of the assembling together of the world's hosts at the -millennium when the lion and the lamb should lie down together and a -little child should lead them. But the pathos, the lesson, the moral of -the great spectacle were lost upon the boy; he only thought of the -conspicuousness of the principal character before the on-looking -nations; his face lit with the thought, and he said to himself that he -wished he could be that child, if it was a tame lion. - -Now he lapsed into suffering again, as the dry argument was resumed. -Presently he bethought him of a treasure he had and got it out. It was -a large black beetle with formidable jaws--a "pinchbug," he called it. -It was in a percussion-cap box. The first thing the beetle did was to -take him by the finger. A natural fillip followed, the beetle went -floundering into the aisle and lit on its back, and the hurt finger -went into the boy's mouth. The beetle lay there working its helpless -legs, unable to turn over. Tom eyed it, and longed for it; but it was -safe out of his reach. Other people uninterested in the sermon found -relief in the beetle, and they eyed it too. Presently a vagrant poodle -dog came idling along, sad at heart, lazy with the summer softness and -the quiet, weary of captivity, sighing for change. He spied the beetle; -the drooping tail lifted and wagged. He surveyed the prize; walked -around it; smelt at it from a safe distance; walked around it again; -grew bolder, and took a closer smell; then lifted his lip and made a -gingerly snatch at it, just missing it; made another, and another; -began to enjoy the diversion; subsided to his stomach with the beetle -between his paws, and continued his experiments; grew weary at last, -and then indifferent and absent-minded. His head nodded, and little by -little his chin descended and touched the enemy, who seized it. There -was a sharp yelp, a flirt of the poodle's head, and the beetle fell a -couple of yards away, and lit on its back once more. The neighboring -spectators shook with a gentle inward joy, several faces went behind -fans and handkerchiefs, and Tom was entirely happy. The dog looked -foolish, and probably felt so; but there was resentment in his heart, -too, and a craving for revenge. So he went to the beetle and began a -wary attack on it again; jumping at it from every point of a circle, -lighting with his fore-paws within an inch of the creature, making even -closer snatches at it with his teeth, and jerking his head till his -ears flapped again. But he grew tired once more, after a while; tried -to amuse himself with a fly but found no relief; followed an ant -around, with his nose close to the floor, and quickly wearied of that; -yawned, sighed, forgot the beetle entirely, and sat down on it. Then -there was a wild yelp of agony and the poodle went sailing up the -aisle; the yelps continued, and so did the dog; he crossed the house in -front of the altar; he flew down the other aisle; he crossed before the -doors; he clamored up the home-stretch; his anguish grew with his -progress, till presently he was but a woolly comet moving in its orbit -with the gleam and the speed of light. At last the frantic sufferer -sheered from its course, and sprang into its master's lap; he flung it -out of the window, and the voice of distress quickly thinned away and -died in the distance. - -By this time the whole church was red-faced and suffocating with -suppressed laughter, and the sermon had come to a dead standstill. The -discourse was resumed presently, but it went lame and halting, all -possibility of impressiveness being at an end; for even the gravest -sentiments were constantly being received with a smothered burst of -unholy mirth, under cover of some remote pew-back, as if the poor -parson had said a rarely facetious thing. It was a genuine relief to -the whole congregation when the ordeal was over and the benediction -pronounced. - -Tom Sawyer went home quite cheerful, thinking to himself that there -was some satisfaction about divine service when there was a bit of -variety in it. He had but one marring thought; he was willing that the -dog should play with his pinchbug, but he did not think it was upright -in him to carry it off. - - - -CHAPTER VI - -MONDAY morning found Tom Sawyer miserable. Monday morning always found -him so--because it began another week's slow suffering in school. He -generally began that day with wishing he had had no intervening -holiday, it made the going into captivity and fetters again so much -more odious. - -Tom lay thinking. Presently it occurred to him that he wished he was -sick; then he could stay home from school. Here was a vague -possibility. He canvassed his system. No ailment was found, and he -investigated again. This time he thought he could detect colicky -symptoms, and he began to encourage them with considerable hope. But -they soon grew feeble, and presently died wholly away. He reflected -further. Suddenly he discovered something. One of his upper front teeth -was loose. This was lucky; he was about to begin to groan, as a -"starter," as he called it, when it occurred to him that if he came -into court with that argument, his aunt would pull it out, and that -would hurt. So he thought he would hold the tooth in reserve for the -present, and seek further. Nothing offered for some little time, and -then he remembered hearing the doctor tell about a certain thing that -laid up a patient for two or three weeks and threatened to make him -lose a finger. So the boy eagerly drew his sore toe from under the -sheet and held it up for inspection. But now he did not know the -necessary symptoms. However, it seemed well worth while to chance it, -so he fell to groaning with considerable spirit. - -But Sid slept on unconscious. - -Tom groaned louder, and fancied that he began to feel pain in the toe. - -No result from Sid. - -Tom was panting with his exertions by this time. He took a rest and -then swelled himself up and fetched a succession of admirable groans. - -Sid snored on. - -Tom was aggravated. He said, "Sid, Sid!" and shook him. This course -worked well, and Tom began to groan again. Sid yawned, stretched, then -brought himself up on his elbow with a snort, and began to stare at -Tom. Tom went on groaning. Sid said: - -"Tom! Say, Tom!" [No response.] "Here, Tom! TOM! What is the matter, -Tom?" And he shook him and looked in his face anxiously. - -Tom moaned out: - -"Oh, don't, Sid. Don't joggle me." - -"Why, what's the matter, Tom? I must call auntie." - -"No--never mind. It'll be over by and by, maybe. Don't call anybody." - -"But I must! DON'T groan so, Tom, it's awful. How long you been this -way?" - -"Hours. Ouch! Oh, don't stir so, Sid, you'll kill me." - -"Tom, why didn't you wake me sooner? Oh, Tom, DON'T! It makes my -flesh crawl to hear you. Tom, what is the matter?" - -"I forgive you everything, Sid. [Groan.] Everything you've ever done -to me. When I'm gone--" - -"Oh, Tom, you ain't dying, are you? Don't, Tom--oh, don't. Maybe--" - -"I forgive everybody, Sid. [Groan.] Tell 'em so, Sid. And Sid, you -give my window-sash and my cat with one eye to that new girl that's -come to town, and tell her--" - -But Sid had snatched his clothes and gone. Tom was suffering in -reality, now, so handsomely was his imagination working, and so his -groans had gathered quite a genuine tone. - -Sid flew down-stairs and said: - -"Oh, Aunt Polly, come! Tom's dying!" - -"Dying!" - -"Yes'm. Don't wait--come quick!" - -"Rubbage! I don't believe it!" - -But she fled up-stairs, nevertheless, with Sid and Mary at her heels. -And her face grew white, too, and her lip trembled. When she reached -the bedside she gasped out: - -"You, Tom! Tom, what's the matter with you?" - -"Oh, auntie, I'm--" - -"What's the matter with you--what is the matter with you, child?" - -"Oh, auntie, my sore toe's mortified!" - -The old lady sank down into a chair and laughed a little, then cried a -little, then did both together. This restored her and she said: - -"Tom, what a turn you did give me. Now you shut up that nonsense and -climb out of this." - -The groans ceased and the pain vanished from the toe. The boy felt a -little foolish, and he said: - -"Aunt Polly, it SEEMED mortified, and it hurt so I never minded my -tooth at all." - -"Your tooth, indeed! What's the matter with your tooth?" - -"One of them's loose, and it aches perfectly awful." - -"There, there, now, don't begin that groaning again. Open your mouth. -Well--your tooth IS loose, but you're not going to die about that. -Mary, get me a silk thread, and a chunk of fire out of the kitchen." - -Tom said: - -"Oh, please, auntie, don't pull it out. It don't hurt any more. I wish -I may never stir if it does. Please don't, auntie. I don't want to stay -home from school." - -"Oh, you don't, don't you? So all this row was because you thought -you'd get to stay home from school and go a-fishing? Tom, Tom, I love -you so, and you seem to try every way you can to break my old heart -with your outrageousness." By this time the dental instruments were -ready. The old lady made one end of the silk thread fast to Tom's tooth -with a loop and tied the other to the bedpost. Then she seized the -chunk of fire and suddenly thrust it almost into the boy's face. The -tooth hung dangling by the bedpost, now. - -But all trials bring their compensations. As Tom wended to school -after breakfast, he was the envy of every boy he met because the gap in -his upper row of teeth enabled him to expectorate in a new and -admirable way. He gathered quite a following of lads interested in the -exhibition; and one that had cut his finger and had been a centre of -fascination and homage up to this time, now found himself suddenly -without an adherent, and shorn of his glory. His heart was heavy, and -he said with a disdain which he did not feel that it wasn't anything to -spit like Tom Sawyer; but another boy said, "Sour grapes!" and he -wandered away a dismantled hero. - -Shortly Tom came upon the juvenile pariah of the village, Huckleberry -Finn, son of the town drunkard. Huckleberry was cordially hated and -dreaded by all the mothers of the town, because he was idle and lawless -and vulgar and bad--and because all their children admired him so, and -delighted in his forbidden society, and wished they dared to be like -him. Tom was like the rest of the respectable boys, in that he envied -Huckleberry his gaudy outcast condition, and was under strict orders -not to play with him. So he played with him every time he got a chance. -Huckleberry was always dressed in the cast-off clothes of full-grown -men, and they were in perennial bloom and fluttering with rags. His hat -was a vast ruin with a wide crescent lopped out of its brim; his coat, -when he wore one, hung nearly to his heels and had the rearward buttons -far down the back; but one suspender supported his trousers; the seat -of the trousers bagged low and contained nothing, the fringed legs -dragged in the dirt when not rolled up. - -Huckleberry came and went, at his own free will. He slept on doorsteps -in fine weather and in empty hogsheads in wet; he did not have to go to -school or to church, or call any being master or obey anybody; he could -go fishing or swimming when and where he chose, and stay as long as it -suited him; nobody forbade him to fight; he could sit up as late as he -pleased; he was always the first boy that went barefoot in the spring -and the last to resume leather in the fall; he never had to wash, nor -put on clean clothes; he could swear wonderfully. In a word, everything -that goes to make life precious that boy had. So thought every -harassed, hampered, respectable boy in St. Petersburg. - -Tom hailed the romantic outcast: - -"Hello, Huckleberry!" - -"Hello yourself, and see how you like it." - -"What's that you got?" - -"Dead cat." - -"Lemme see him, Huck. My, he's pretty stiff. Where'd you get him?" - -"Bought him off'n a boy." - -"What did you give?" - -"I give a blue ticket and a bladder that I got at the slaughter-house." - -"Where'd you get the blue ticket?" - -"Bought it off'n Ben Rogers two weeks ago for a hoop-stick." - -"Say--what is dead cats good for, Huck?" - -"Good for? Cure warts with." - -"No! Is that so? I know something that's better." - -"I bet you don't. What is it?" - -"Why, spunk-water." - -"Spunk-water! I wouldn't give a dern for spunk-water." - -"You wouldn't, wouldn't you? D'you ever try it?" - -"No, I hain't. But Bob Tanner did." - -"Who told you so!" - -"Why, he told Jeff Thatcher, and Jeff told Johnny Baker, and Johnny -told Jim Hollis, and Jim told Ben Rogers, and Ben told a nigger, and -the nigger told me. There now!" - -"Well, what of it? They'll all lie. Leastways all but the nigger. I -don't know HIM. But I never see a nigger that WOULDN'T lie. Shucks! Now -you tell me how Bob Tanner done it, Huck." - -"Why, he took and dipped his hand in a rotten stump where the -rain-water was." - -"In the daytime?" - -"Certainly." - -"With his face to the stump?" - -"Yes. Least I reckon so." - -"Did he say anything?" - -"I don't reckon he did. I don't know." - -"Aha! Talk about trying to cure warts with spunk-water such a blame -fool way as that! Why, that ain't a-going to do any good. You got to go -all by yourself, to the middle of the woods, where you know there's a -spunk-water stump, and just as it's midnight you back up against the -stump and jam your hand in and say: - - 'Barley-corn, barley-corn, injun-meal shorts, - Spunk-water, spunk-water, swaller these warts,' - -and then walk away quick, eleven steps, with your eyes shut, and then -turn around three times and walk home without speaking to anybody. -Because if you speak the charm's busted." - -"Well, that sounds like a good way; but that ain't the way Bob Tanner -done." - -"No, sir, you can bet he didn't, becuz he's the wartiest boy in this -town; and he wouldn't have a wart on him if he'd knowed how to work -spunk-water. I've took off thousands of warts off of my hands that way, -Huck. I play with frogs so much that I've always got considerable many -warts. Sometimes I take 'em off with a bean." - -"Yes, bean's good. I've done that." - -"Have you? What's your way?" - -"You take and split the bean, and cut the wart so as to get some -blood, and then you put the blood on one piece of the bean and take and -dig a hole and bury it 'bout midnight at the crossroads in the dark of -the moon, and then you burn up the rest of the bean. You see that piece -that's got the blood on it will keep drawing and drawing, trying to -fetch the other piece to it, and so that helps the blood to draw the -wart, and pretty soon off she comes." - -"Yes, that's it, Huck--that's it; though when you're burying it if you -say 'Down bean; off wart; come no more to bother me!' it's better. -That's the way Joe Harper does, and he's been nearly to Coonville and -most everywheres. But say--how do you cure 'em with dead cats?" - -"Why, you take your cat and go and get in the graveyard 'long about -midnight when somebody that was wicked has been buried; and when it's -midnight a devil will come, or maybe two or three, but you can't see -'em, you can only hear something like the wind, or maybe hear 'em talk; -and when they're taking that feller away, you heave your cat after 'em -and say, 'Devil follow corpse, cat follow devil, warts follow cat, I'm -done with ye!' That'll fetch ANY wart." - -"Sounds right. D'you ever try it, Huck?" - -"No, but old Mother Hopkins told me." - -"Well, I reckon it's so, then. Becuz they say she's a witch." - -"Say! Why, Tom, I KNOW she is. She witched pap. Pap says so his own -self. He come along one day, and he see she was a-witching him, so he -took up a rock, and if she hadn't dodged, he'd a got her. Well, that -very night he rolled off'n a shed wher' he was a layin drunk, and broke -his arm." - -"Why, that's awful. How did he know she was a-witching him?" - -"Lord, pap can tell, easy. Pap says when they keep looking at you -right stiddy, they're a-witching you. Specially if they mumble. Becuz -when they mumble they're saying the Lord's Prayer backards." - -"Say, Hucky, when you going to try the cat?" - -"To-night. I reckon they'll come after old Hoss Williams to-night." - -"But they buried him Saturday. Didn't they get him Saturday night?" - -"Why, how you talk! How could their charms work till midnight?--and -THEN it's Sunday. Devils don't slosh around much of a Sunday, I don't -reckon." - -"I never thought of that. That's so. Lemme go with you?" - -"Of course--if you ain't afeard." - -"Afeard! 'Tain't likely. Will you meow?" - -"Yes--and you meow back, if you get a chance. Last time, you kep' me -a-meowing around till old Hays went to throwing rocks at me and says -'Dern that cat!' and so I hove a brick through his window--but don't -you tell." - -"I won't. I couldn't meow that night, becuz auntie was watching me, -but I'll meow this time. Say--what's that?" - -"Nothing but a tick." - -"Where'd you get him?" - -"Out in the woods." - -"What'll you take for him?" - -"I don't know. I don't want to sell him." - -"All right. It's a mighty small tick, anyway." - -"Oh, anybody can run a tick down that don't belong to them. I'm -satisfied with it. It's a good enough tick for me." - -"Sho, there's ticks a plenty. I could have a thousand of 'em if I -wanted to." - -"Well, why don't you? Becuz you know mighty well you can't. This is a -pretty early tick, I reckon. It's the first one I've seen this year." - -"Say, Huck--I'll give you my tooth for him." - -"Less see it." - -Tom got out a bit of paper and carefully unrolled it. Huckleberry -viewed it wistfully. The temptation was very strong. At last he said: - -"Is it genuwyne?" - -Tom lifted his lip and showed the vacancy. - -"Well, all right," said Huckleberry, "it's a trade." - -Tom enclosed the tick in the percussion-cap box that had lately been -the pinchbug's prison, and the boys separated, each feeling wealthier -than before. - -When Tom reached the little isolated frame schoolhouse, he strode in -briskly, with the manner of one who had come with all honest speed. -He hung his hat on a peg and flung himself into his seat with -business-like alacrity. The master, throned on high in his great -splint-bottom arm-chair, was dozing, lulled by the drowsy hum of study. -The interruption roused him. - -"Thomas Sawyer!" - -Tom knew that when his name was pronounced in full, it meant trouble. - -"Sir!" - -"Come up here. Now, sir, why are you late again, as usual?" - -Tom was about to take refuge in a lie, when he saw two long tails of -yellow hair hanging down a back that he recognized by the electric -sympathy of love; and by that form was THE ONLY VACANT PLACE on the -girls' side of the schoolhouse. He instantly said: - -"I STOPPED TO TALK WITH HUCKLEBERRY FINN!" - -The master's pulse stood still, and he stared helplessly. The buzz of -study ceased. The pupils wondered if this foolhardy boy had lost his -mind. The master said: - -"You--you did what?" - -"Stopped to talk with Huckleberry Finn." - -There was no mistaking the words. - -"Thomas Sawyer, this is the most astounding confession I have ever -listened to. No mere ferule will answer for this offence. Take off your -jacket." - -The master's arm performed until it was tired and the stock of -switches notably diminished. Then the order followed: - -"Now, sir, go and sit with the girls! And let this be a warning to you." - -The titter that rippled around the room appeared to abash the boy, but -in reality that result was caused rather more by his worshipful awe of -his unknown idol and the dread pleasure that lay in his high good -fortune. He sat down upon the end of the pine bench and the girl -hitched herself away from him with a toss of her head. Nudges and winks -and whispers traversed the room, but Tom sat still, with his arms upon -the long, low desk before him, and seemed to study his book. - -By and by attention ceased from him, and the accustomed school murmur -rose upon the dull air once more. Presently the boy began to steal -furtive glances at the girl. She observed it, "made a mouth" at him and -gave him the back of her head for the space of a minute. When she -cautiously faced around again, a peach lay before her. She thrust it -away. Tom gently put it back. She thrust it away again, but with less -animosity. Tom patiently returned it to its place. Then she let it -remain. Tom scrawled on his slate, "Please take it--I got more." The -girl glanced at the words, but made no sign. Now the boy began to draw -something on the slate, hiding his work with his left hand. For a time -the girl refused to notice; but her human curiosity presently began to -manifest itself by hardly perceptible signs. The boy worked on, -apparently unconscious. The girl made a sort of noncommittal attempt to -see, but the boy did not betray that he was aware of it. At last she -gave in and hesitatingly whispered: - -"Let me see it." - -Tom partly uncovered a dismal caricature of a house with two gable -ends to it and a corkscrew of smoke issuing from the chimney. Then the -girl's interest began to fasten itself upon the work and she forgot -everything else. When it was finished, she gazed a moment, then -whispered: - -"It's nice--make a man." - -The artist erected a man in the front yard, that resembled a derrick. -He could have stepped over the house; but the girl was not -hypercritical; she was satisfied with the monster, and whispered: - -"It's a beautiful man--now make me coming along." - -Tom drew an hour-glass with a full moon and straw limbs to it and -armed the spreading fingers with a portentous fan. The girl said: - -"It's ever so nice--I wish I could draw." - -"It's easy," whispered Tom, "I'll learn you." - -"Oh, will you? When?" - -"At noon. Do you go home to dinner?" - -"I'll stay if you will." - -"Good--that's a whack. What's your name?" - -"Becky Thatcher. What's yours? Oh, I know. It's Thomas Sawyer." - -"That's the name they lick me by. I'm Tom when I'm good. You call me -Tom, will you?" - -"Yes." - -Now Tom began to scrawl something on the slate, hiding the words from -the girl. But she was not backward this time. She begged to see. Tom -said: - -"Oh, it ain't anything." - -"Yes it is." - -"No it ain't. You don't want to see." - -"Yes I do, indeed I do. Please let me." - -"You'll tell." - -"No I won't--deed and deed and double deed won't." - -"You won't tell anybody at all? Ever, as long as you live?" - -"No, I won't ever tell ANYbody. Now let me." - -"Oh, YOU don't want to see!" - -"Now that you treat me so, I WILL see." And she put her small hand -upon his and a little scuffle ensued, Tom pretending to resist in -earnest but letting his hand slip by degrees till these words were -revealed: "I LOVE YOU." - -"Oh, you bad thing!" And she hit his hand a smart rap, but reddened -and looked pleased, nevertheless. - -Just at this juncture the boy felt a slow, fateful grip closing on his -ear, and a steady lifting impulse. In that wise he was borne across the -house and deposited in his own seat, under a peppering fire of giggles -from the whole school. Then the master stood over him during a few -awful moments, and finally moved away to his throne without saying a -word. But although Tom's ear tingled, his heart was jubilant. - -As the school quieted down Tom made an honest effort to study, but the -turmoil within him was too great. In turn he took his place in the -reading class and made a botch of it; then in the geography class and -turned lakes into mountains, mountains into rivers, and rivers into -continents, till chaos was come again; then in the spelling class, and -got "turned down," by a succession of mere baby words, till he brought -up at the foot and yielded up the pewter medal which he had worn with -ostentation for months. - - - -CHAPTER VII - -THE harder Tom tried to fasten his mind on his book, the more his -ideas wandered. So at last, with a sigh and a yawn, he gave it up. It -seemed to him that the noon recess would never come. The air was -utterly dead. There was not a breath stirring. It was the sleepiest of -sleepy days. The drowsing murmur of the five and twenty studying -scholars soothed the soul like the spell that is in the murmur of bees. -Away off in the flaming sunshine, Cardiff Hill lifted its soft green -sides through a shimmering veil of heat, tinted with the purple of -distance; a few birds floated on lazy wing high in the air; no other -living thing was visible but some cows, and they were asleep. Tom's -heart ached to be free, or else to have something of interest to do to -pass the dreary time. His hand wandered into his pocket and his face -lit up with a glow of gratitude that was prayer, though he did not know -it. Then furtively the percussion-cap box came out. He released the -tick and put him on the long flat desk. The creature probably glowed -with a gratitude that amounted to prayer, too, at this moment, but it -was premature: for when he started thankfully to travel off, Tom turned -him aside with a pin and made him take a new direction. - -Tom's bosom friend sat next him, suffering just as Tom had been, and -now he was deeply and gratefully interested in this entertainment in an -instant. This bosom friend was Joe Harper. The two boys were sworn -friends all the week, and embattled enemies on Saturdays. Joe took a -pin out of his lapel and began to assist in exercising the prisoner. -The sport grew in interest momently. Soon Tom said that they were -interfering with each other, and neither getting the fullest benefit of -the tick. So he put Joe's slate on the desk and drew a line down the -middle of it from top to bottom. - -"Now," said he, "as long as he is on your side you can stir him up and -I'll let him alone; but if you let him get away and get on my side, -you're to leave him alone as long as I can keep him from crossing over." - -"All right, go ahead; start him up." - -The tick escaped from Tom, presently, and crossed the equator. Joe -harassed him awhile, and then he got away and crossed back again. This -change of base occurred often. While one boy was worrying the tick with -absorbing interest, the other would look on with interest as strong, -the two heads bowed together over the slate, and the two souls dead to -all things else. At last luck seemed to settle and abide with Joe. The -tick tried this, that, and the other course, and got as excited and as -anxious as the boys themselves, but time and again just as he would -have victory in his very grasp, so to speak, and Tom's fingers would be -twitching to begin, Joe's pin would deftly head him off, and keep -possession. At last Tom could stand it no longer. The temptation was -too strong. So he reached out and lent a hand with his pin. Joe was -angry in a moment. Said he: - -"Tom, you let him alone." - -"I only just want to stir him up a little, Joe." - -"No, sir, it ain't fair; you just let him alone." - -"Blame it, I ain't going to stir him much." - -"Let him alone, I tell you." - -"I won't!" - -"You shall--he's on my side of the line." - -"Look here, Joe Harper, whose is that tick?" - -"I don't care whose tick he is--he's on my side of the line, and you -sha'n't touch him." - -"Well, I'll just bet I will, though. He's my tick and I'll do what I -blame please with him, or die!" - -A tremendous whack came down on Tom's shoulders, and its duplicate on -Joe's; and for the space of two minutes the dust continued to fly from -the two jackets and the whole school to enjoy it. The boys had been too -absorbed to notice the hush that had stolen upon the school awhile -before when the master came tiptoeing down the room and stood over -them. He had contemplated a good part of the performance before he -contributed his bit of variety to it. - -When school broke up at noon, Tom flew to Becky Thatcher, and -whispered in her ear: - -"Put on your bonnet and let on you're going home; and when you get to -the corner, give the rest of 'em the slip, and turn down through the -lane and come back. I'll go the other way and come it over 'em the same -way." - -So the one went off with one group of scholars, and the other with -another. In a little while the two met at the bottom of the lane, and -when they reached the school they had it all to themselves. Then they -sat together, with a slate before them, and Tom gave Becky the pencil -and held her hand in his, guiding it, and so created another surprising -house. When the interest in art began to wane, the two fell to talking. -Tom was swimming in bliss. He said: - -"Do you love rats?" - -"No! I hate them!" - -"Well, I do, too--LIVE ones. But I mean dead ones, to swing round your -head with a string." - -"No, I don't care for rats much, anyway. What I like is chewing-gum." - -"Oh, I should say so! I wish I had some now." - -"Do you? I've got some. I'll let you chew it awhile, but you must give -it back to me." - -That was agreeable, so they chewed it turn about, and dangled their -legs against the bench in excess of contentment. - -"Was you ever at a circus?" said Tom. - -"Yes, and my pa's going to take me again some time, if I'm good." - -"I been to the circus three or four times--lots of times. Church ain't -shucks to a circus. There's things going on at a circus all the time. -I'm going to be a clown in a circus when I grow up." - -"Oh, are you! That will be nice. They're so lovely, all spotted up." - -"Yes, that's so. And they get slathers of money--most a dollar a day, -Ben Rogers says. Say, Becky, was you ever engaged?" - -"What's that?" - -"Why, engaged to be married." - -"No." - -"Would you like to?" - -"I reckon so. I don't know. What is it like?" - -"Like? Why it ain't like anything. You only just tell a boy you won't -ever have anybody but him, ever ever ever, and then you kiss and that's -all. Anybody can do it." - -"Kiss? What do you kiss for?" - -"Why, that, you know, is to--well, they always do that." - -"Everybody?" - -"Why, yes, everybody that's in love with each other. Do you remember -what I wrote on the slate?" - -"Ye--yes." - -"What was it?" - -"I sha'n't tell you." - -"Shall I tell YOU?" - -"Ye--yes--but some other time." - -"No, now." - -"No, not now--to-morrow." - -"Oh, no, NOW. Please, Becky--I'll whisper it, I'll whisper it ever so -easy." - -Becky hesitating, Tom took silence for consent, and passed his arm -about her waist and whispered the tale ever so softly, with his mouth -close to her ear. And then he added: - -"Now you whisper it to me--just the same." - -She resisted, for a while, and then said: - -"You turn your face away so you can't see, and then I will. But you -mustn't ever tell anybody--WILL you, Tom? Now you won't, WILL you?" - -"No, indeed, indeed I won't. Now, Becky." - -He turned his face away. She bent timidly around till her breath -stirred his curls and whispered, "I--love--you!" - -Then she sprang away and ran around and around the desks and benches, -with Tom after her, and took refuge in a corner at last, with her -little white apron to her face. Tom clasped her about her neck and -pleaded: - -"Now, Becky, it's all done--all over but the kiss. Don't you be afraid -of that--it ain't anything at all. Please, Becky." And he tugged at her -apron and the hands. - -By and by she gave up, and let her hands drop; her face, all glowing -with the struggle, came up and submitted. Tom kissed the red lips and -said: - -"Now it's all done, Becky. And always after this, you know, you ain't -ever to love anybody but me, and you ain't ever to marry anybody but -me, ever never and forever. Will you?" - -"No, I'll never love anybody but you, Tom, and I'll never marry -anybody but you--and you ain't to ever marry anybody but me, either." - -"Certainly. Of course. That's PART of it. And always coming to school -or when we're going home, you're to walk with me, when there ain't -anybody looking--and you choose me and I choose you at parties, because -that's the way you do when you're engaged." - -"It's so nice. I never heard of it before." - -"Oh, it's ever so gay! Why, me and Amy Lawrence--" - -The big eyes told Tom his blunder and he stopped, confused. - -"Oh, Tom! Then I ain't the first you've ever been engaged to!" - -The child began to cry. Tom said: - -"Oh, don't cry, Becky, I don't care for her any more." - -"Yes, you do, Tom--you know you do." - -Tom tried to put his arm about her neck, but she pushed him away and -turned her face to the wall, and went on crying. Tom tried again, with -soothing words in his mouth, and was repulsed again. Then his pride was -up, and he strode away and went outside. He stood about, restless and -uneasy, for a while, glancing at the door, every now and then, hoping -she would repent and come to find him. But she did not. Then he began -to feel badly and fear that he was in the wrong. It was a hard struggle -with him to make new advances, now, but he nerved himself to it and -entered. She was still standing back there in the corner, sobbing, with -her face to the wall. Tom's heart smote him. He went to her and stood a -moment, not knowing exactly how to proceed. Then he said hesitatingly: - -"Becky, I--I don't care for anybody but you." - -No reply--but sobs. - -"Becky"--pleadingly. "Becky, won't you say something?" - -More sobs. - -Tom got out his chiefest jewel, a brass knob from the top of an -andiron, and passed it around her so that she could see it, and said: - -"Please, Becky, won't you take it?" - -She struck it to the floor. Then Tom marched out of the house and over -the hills and far away, to return to school no more that day. Presently -Becky began to suspect. She ran to the door; he was not in sight; she -flew around to the play-yard; he was not there. Then she called: - -"Tom! Come back, Tom!" - -She listened intently, but there was no answer. She had no companions -but silence and loneliness. So she sat down to cry again and upbraid -herself; and by this time the scholars began to gather again, and she -had to hide her griefs and still her broken heart and take up the cross -of a long, dreary, aching afternoon, with none among the strangers -about her to exchange sorrows with. - - - -CHAPTER VIII - -TOM dodged hither and thither through lanes until he was well out of -the track of returning scholars, and then fell into a moody jog. He -crossed a small "branch" two or three times, because of a prevailing -juvenile superstition that to cross water baffled pursuit. Half an hour -later he was disappearing behind the Douglas mansion on the summit of -Cardiff Hill, and the schoolhouse was hardly distinguishable away off -in the valley behind him. He entered a dense wood, picked his pathless -way to the centre of it, and sat down on a mossy spot under a spreading -oak. There was not even a zephyr stirring; the dead noonday heat had -even stilled the songs of the birds; nature lay in a trance that was -broken by no sound but the occasional far-off hammering of a -woodpecker, and this seemed to render the pervading silence and sense -of loneliness the more profound. The boy's soul was steeped in -melancholy; his feelings were in happy accord with his surroundings. He -sat long with his elbows on his knees and his chin in his hands, -meditating. It seemed to him that life was but a trouble, at best, and -he more than half envied Jimmy Hodges, so lately released; it must be -very peaceful, he thought, to lie and slumber and dream forever and -ever, with the wind whispering through the trees and caressing the -grass and the flowers over the grave, and nothing to bother and grieve -about, ever any more. If he only had a clean Sunday-school record he -could be willing to go, and be done with it all. Now as to this girl. -What had he done? Nothing. He had meant the best in the world, and been -treated like a dog--like a very dog. She would be sorry some day--maybe -when it was too late. Ah, if he could only die TEMPORARILY! - -But the elastic heart of youth cannot be compressed into one -constrained shape long at a time. Tom presently began to drift -insensibly back into the concerns of this life again. What if he turned -his back, now, and disappeared mysteriously? What if he went away--ever -so far away, into unknown countries beyond the seas--and never came -back any more! How would she feel then! The idea of being a clown -recurred to him now, only to fill him with disgust. For frivolity and -jokes and spotted tights were an offense, when they intruded themselves -upon a spirit that was exalted into the vague august realm of the -romantic. No, he would be a soldier, and return after long years, all -war-worn and illustrious. No--better still, he would join the Indians, -and hunt buffaloes and go on the warpath in the mountain ranges and the -trackless great plains of the Far West, and away in the future come -back a great chief, bristling with feathers, hideous with paint, and -prance into Sunday-school, some drowsy summer morning, with a -bloodcurdling war-whoop, and sear the eyeballs of all his companions -with unappeasable envy. But no, there was something gaudier even than -this. He would be a pirate! That was it! NOW his future lay plain -before him, and glowing with unimaginable splendor. How his name would -fill the world, and make people shudder! How gloriously he would go -plowing the dancing seas, in his long, low, black-hulled racer, the -Spirit of the Storm, with his grisly flag flying at the fore! And at -the zenith of his fame, how he would suddenly appear at the old village -and stalk into church, brown and weather-beaten, in his black velvet -doublet and trunks, his great jack-boots, his crimson sash, his belt -bristling with horse-pistols, his crime-rusted cutlass at his side, his -slouch hat with waving plumes, his black flag unfurled, with the skull -and crossbones on it, and hear with swelling ecstasy the whisperings, -"It's Tom Sawyer the Pirate!--the Black Avenger of the Spanish Main!" - -Yes, it was settled; his career was determined. He would run away from -home and enter upon it. He would start the very next morning. Therefore -he must now begin to get ready. He would collect his resources -together. He went to a rotten log near at hand and began to dig under -one end of it with his Barlow knife. He soon struck wood that sounded -hollow. He put his hand there and uttered this incantation impressively: - -"What hasn't come here, come! What's here, stay here!" - -Then he scraped away the dirt, and exposed a pine shingle. He took it -up and disclosed a shapely little treasure-house whose bottom and sides -were of shingles. In it lay a marble. Tom's astonishment was boundless! -He scratched his head with a perplexed air, and said: - -"Well, that beats anything!" - -Then he tossed the marble away pettishly, and stood cogitating. The -truth was, that a superstition of his had failed, here, which he and -all his comrades had always looked upon as infallible. If you buried a -marble with certain necessary incantations, and left it alone a -fortnight, and then opened the place with the incantation he had just -used, you would find that all the marbles you had ever lost had -gathered themselves together there, meantime, no matter how widely they -had been separated. But now, this thing had actually and unquestionably -failed. Tom's whole structure of faith was shaken to its foundations. -He had many a time heard of this thing succeeding but never of its -failing before. It did not occur to him that he had tried it several -times before, himself, but could never find the hiding-places -afterward. He puzzled over the matter some time, and finally decided -that some witch had interfered and broken the charm. He thought he -would satisfy himself on that point; so he searched around till he -found a small sandy spot with a little funnel-shaped depression in it. -He laid himself down and put his mouth close to this depression and -called-- - -"Doodle-bug, doodle-bug, tell me what I want to know! Doodle-bug, -doodle-bug, tell me what I want to know!" - -The sand began to work, and presently a small black bug appeared for a -second and then darted under again in a fright. - -"He dasn't tell! So it WAS a witch that done it. I just knowed it." - -He well knew the futility of trying to contend against witches, so he -gave up discouraged. But it occurred to him that he might as well have -the marble he had just thrown away, and therefore he went and made a -patient search for it. But he could not find it. Now he went back to -his treasure-house and carefully placed himself just as he had been -standing when he tossed the marble away; then he took another marble -from his pocket and tossed it in the same way, saying: - -"Brother, go find your brother!" - -He watched where it stopped, and went there and looked. But it must -have fallen short or gone too far; so he tried twice more. The last -repetition was successful. The two marbles lay within a foot of each -other. - -Just here the blast of a toy tin trumpet came faintly down the green -aisles of the forest. Tom flung off his jacket and trousers, turned a -suspender into a belt, raked away some brush behind the rotten log, -disclosing a rude bow and arrow, a lath sword and a tin trumpet, and in -a moment had seized these things and bounded away, barelegged, with -fluttering shirt. He presently halted under a great elm, blew an -answering blast, and then began to tiptoe and look warily out, this way -and that. He said cautiously--to an imaginary company: - -"Hold, my merry men! Keep hid till I blow." - -Now appeared Joe Harper, as airily clad and elaborately armed as Tom. -Tom called: - -"Hold! Who comes here into Sherwood Forest without my pass?" - -"Guy of Guisborne wants no man's pass. Who art thou that--that--" - -"Dares to hold such language," said Tom, prompting--for they talked -"by the book," from memory. - -"Who art thou that dares to hold such language?" - -"I, indeed! I am Robin Hood, as thy caitiff carcase soon shall know." - -"Then art thou indeed that famous outlaw? Right gladly will I dispute -with thee the passes of the merry wood. Have at thee!" - -They took their lath swords, dumped their other traps on the ground, -struck a fencing attitude, foot to foot, and began a grave, careful -combat, "two up and two down." Presently Tom said: - -"Now, if you've got the hang, go it lively!" - -So they "went it lively," panting and perspiring with the work. By and -by Tom shouted: - -"Fall! fall! Why don't you fall?" - -"I sha'n't! Why don't you fall yourself? You're getting the worst of -it." - -"Why, that ain't anything. I can't fall; that ain't the way it is in -the book. The book says, 'Then with one back-handed stroke he slew poor -Guy of Guisborne.' You're to turn around and let me hit you in the -back." - -There was no getting around the authorities, so Joe turned, received -the whack and fell. - -"Now," said Joe, getting up, "you got to let me kill YOU. That's fair." - -"Why, I can't do that, it ain't in the book." - -"Well, it's blamed mean--that's all." - -"Well, say, Joe, you can be Friar Tuck or Much the miller's son, and -lam me with a quarter-staff; or I'll be the Sheriff of Nottingham and -you be Robin Hood a little while and kill me." - -This was satisfactory, and so these adventures were carried out. Then -Tom became Robin Hood again, and was allowed by the treacherous nun to -bleed his strength away through his neglected wound. And at last Joe, -representing a whole tribe of weeping outlaws, dragged him sadly forth, -gave his bow into his feeble hands, and Tom said, "Where this arrow -falls, there bury poor Robin Hood under the greenwood tree." Then he -shot the arrow and fell back and would have died, but he lit on a -nettle and sprang up too gaily for a corpse. - -The boys dressed themselves, hid their accoutrements, and went off -grieving that there were no outlaws any more, and wondering what modern -civilization could claim to have done to compensate for their loss. -They said they would rather be outlaws a year in Sherwood Forest than -President of the United States forever. - - - -CHAPTER IX - -AT half-past nine, that night, Tom and Sid were sent to bed, as usual. -They said their prayers, and Sid was soon asleep. Tom lay awake and -waited, in restless impatience. When it seemed to him that it must be -nearly daylight, he heard the clock strike ten! This was despair. He -would have tossed and fidgeted, as his nerves demanded, but he was -afraid he might wake Sid. So he lay still, and stared up into the dark. -Everything was dismally still. By and by, out of the stillness, little, -scarcely perceptible noises began to emphasize themselves. The ticking -of the clock began to bring itself into notice. Old beams began to -crack mysteriously. The stairs creaked faintly. Evidently spirits were -abroad. A measured, muffled snore issued from Aunt Polly's chamber. And -now the tiresome chirping of a cricket that no human ingenuity could -locate, began. Next the ghastly ticking of a deathwatch in the wall at -the bed's head made Tom shudder--it meant that somebody's days were -numbered. Then the howl of a far-off dog rose on the night air, and was -answered by a fainter howl from a remoter distance. Tom was in an -agony. At last he was satisfied that time had ceased and eternity -begun; he began to doze, in spite of himself; the clock chimed eleven, -but he did not hear it. And then there came, mingling with his -half-formed dreams, a most melancholy caterwauling. The raising of a -neighboring window disturbed him. A cry of "Scat! you devil!" and the -crash of an empty bottle against the back of his aunt's woodshed -brought him wide awake, and a single minute later he was dressed and -out of the window and creeping along the roof of the "ell" on all -fours. He "meow'd" with caution once or twice, as he went; then jumped -to the roof of the woodshed and thence to the ground. Huckleberry Finn -was there, with his dead cat. The boys moved off and disappeared in the -gloom. At the end of half an hour they were wading through the tall -grass of the graveyard. - -It was a graveyard of the old-fashioned Western kind. It was on a -hill, about a mile and a half from the village. It had a crazy board -fence around it, which leaned inward in places, and outward the rest of -the time, but stood upright nowhere. Grass and weeds grew rank over the -whole cemetery. All the old graves were sunken in, there was not a -tombstone on the place; round-topped, worm-eaten boards staggered over -the graves, leaning for support and finding none. "Sacred to the memory -of" So-and-So had been painted on them once, but it could no longer -have been read, on the most of them, now, even if there had been light. - -A faint wind moaned through the trees, and Tom feared it might be the -spirits of the dead, complaining at being disturbed. The boys talked -little, and only under their breath, for the time and the place and the -pervading solemnity and silence oppressed their spirits. They found the -sharp new heap they were seeking, and ensconced themselves within the -protection of three great elms that grew in a bunch within a few feet -of the grave. - -Then they waited in silence for what seemed a long time. The hooting -of a distant owl was all the sound that troubled the dead stillness. -Tom's reflections grew oppressive. He must force some talk. So he said -in a whisper: - -"Hucky, do you believe the dead people like it for us to be here?" - -Huckleberry whispered: - -"I wisht I knowed. It's awful solemn like, AIN'T it?" - -"I bet it is." - -There was a considerable pause, while the boys canvassed this matter -inwardly. Then Tom whispered: - -"Say, Hucky--do you reckon Hoss Williams hears us talking?" - -"O' course he does. Least his sperrit does." - -Tom, after a pause: - -"I wish I'd said Mister Williams. But I never meant any harm. -Everybody calls him Hoss." - -"A body can't be too partic'lar how they talk 'bout these-yer dead -people, Tom." - -This was a damper, and conversation died again. - -Presently Tom seized his comrade's arm and said: - -"Sh!" - -"What is it, Tom?" And the two clung together with beating hearts. - -"Sh! There 'tis again! Didn't you hear it?" - -"I--" - -"There! Now you hear it." - -"Lord, Tom, they're coming! They're coming, sure. What'll we do?" - -"I dono. Think they'll see us?" - -"Oh, Tom, they can see in the dark, same as cats. I wisht I hadn't -come." - -"Oh, don't be afeard. I don't believe they'll bother us. We ain't -doing any harm. If we keep perfectly still, maybe they won't notice us -at all." - -"I'll try to, Tom, but, Lord, I'm all of a shiver." - -"Listen!" - -The boys bent their heads together and scarcely breathed. A muffled -sound of voices floated up from the far end of the graveyard. - -"Look! See there!" whispered Tom. "What is it?" - -"It's devil-fire. Oh, Tom, this is awful." - -Some vague figures approached through the gloom, swinging an -old-fashioned tin lantern that freckled the ground with innumerable -little spangles of light. Presently Huckleberry whispered with a -shudder: - -"It's the devils sure enough. Three of 'em! Lordy, Tom, we're goners! -Can you pray?" - -"I'll try, but don't you be afeard. They ain't going to hurt us. 'Now -I lay me down to sleep, I--'" - -"Sh!" - -"What is it, Huck?" - -"They're HUMANS! One of 'em is, anyway. One of 'em's old Muff Potter's -voice." - -"No--'tain't so, is it?" - -"I bet I know it. Don't you stir nor budge. He ain't sharp enough to -notice us. Drunk, the same as usual, likely--blamed old rip!" - -"All right, I'll keep still. Now they're stuck. Can't find it. Here -they come again. Now they're hot. Cold again. Hot again. Red hot! -They're p'inted right, this time. Say, Huck, I know another o' them -voices; it's Injun Joe." - -"That's so--that murderin' half-breed! I'd druther they was devils a -dern sight. What kin they be up to?" - -The whisper died wholly out, now, for the three men had reached the -grave and stood within a few feet of the boys' hiding-place. - -"Here it is," said the third voice; and the owner of it held the -lantern up and revealed the face of young Doctor Robinson. - -Potter and Injun Joe were carrying a handbarrow with a rope and a -couple of shovels on it. They cast down their load and began to open -the grave. The doctor put the lantern at the head of the grave and came -and sat down with his back against one of the elm trees. He was so -close the boys could have touched him. - -"Hurry, men!" he said, in a low voice; "the moon might come out at any -moment." - -They growled a response and went on digging. For some time there was -no noise but the grating sound of the spades discharging their freight -of mould and gravel. It was very monotonous. Finally a spade struck -upon the coffin with a dull woody accent, and within another minute or -two the men had hoisted it out on the ground. They pried off the lid -with their shovels, got out the body and dumped it rudely on the -ground. The moon drifted from behind the clouds and exposed the pallid -face. The barrow was got ready and the corpse placed on it, covered -with a blanket, and bound to its place with the rope. Potter took out a -large spring-knife and cut off the dangling end of the rope and then -said: - -"Now the cussed thing's ready, Sawbones, and you'll just out with -another five, or here she stays." - -"That's the talk!" said Injun Joe. - -"Look here, what does this mean?" said the doctor. "You required your -pay in advance, and I've paid you." - -"Yes, and you done more than that," said Injun Joe, approaching the -doctor, who was now standing. "Five years ago you drove me away from -your father's kitchen one night, when I come to ask for something to -eat, and you said I warn't there for any good; and when I swore I'd get -even with you if it took a hundred years, your father had me jailed for -a vagrant. Did you think I'd forget? The Injun blood ain't in me for -nothing. And now I've GOT you, and you got to SETTLE, you know!" - -He was threatening the doctor, with his fist in his face, by this -time. The doctor struck out suddenly and stretched the ruffian on the -ground. Potter dropped his knife, and exclaimed: - -"Here, now, don't you hit my pard!" and the next moment he had -grappled with the doctor and the two were struggling with might and -main, trampling the grass and tearing the ground with their heels. -Injun Joe sprang to his feet, his eyes flaming with passion, snatched -up Potter's knife, and went creeping, catlike and stooping, round and -round about the combatants, seeking an opportunity. All at once the -doctor flung himself free, seized the heavy headboard of Williams' -grave and felled Potter to the earth with it--and in the same instant -the half-breed saw his chance and drove the knife to the hilt in the -young man's breast. He reeled and fell partly upon Potter, flooding him -with his blood, and in the same moment the clouds blotted out the -dreadful spectacle and the two frightened boys went speeding away in -the dark. - -Presently, when the moon emerged again, Injun Joe was standing over -the two forms, contemplating them. The doctor murmured inarticulately, -gave a long gasp or two and was still. The half-breed muttered: - -"THAT score is settled--damn you." - -Then he robbed the body. After which he put the fatal knife in -Potter's open right hand, and sat down on the dismantled coffin. Three ---four--five minutes passed, and then Potter began to stir and moan. His -hand closed upon the knife; he raised it, glanced at it, and let it -fall, with a shudder. Then he sat up, pushing the body from him, and -gazed at it, and then around him, confusedly. His eyes met Joe's. - -"Lord, how is this, Joe?" he said. - -"It's a dirty business," said Joe, without moving. - -"What did you do it for?" - -"I! I never done it!" - -"Look here! That kind of talk won't wash." - -Potter trembled and grew white. - -"I thought I'd got sober. I'd no business to drink to-night. But it's -in my head yet--worse'n when we started here. I'm all in a muddle; -can't recollect anything of it, hardly. Tell me, Joe--HONEST, now, old -feller--did I do it? Joe, I never meant to--'pon my soul and honor, I -never meant to, Joe. Tell me how it was, Joe. Oh, it's awful--and him -so young and promising." - -"Why, you two was scuffling, and he fetched you one with the headboard -and you fell flat; and then up you come, all reeling and staggering -like, and snatched the knife and jammed it into him, just as he fetched -you another awful clip--and here you've laid, as dead as a wedge til -now." - -"Oh, I didn't know what I was a-doing. I wish I may die this minute if -I did. It was all on account of the whiskey and the excitement, I -reckon. I never used a weepon in my life before, Joe. I've fought, but -never with weepons. They'll all say that. Joe, don't tell! Say you -won't tell, Joe--that's a good feller. I always liked you, Joe, and -stood up for you, too. Don't you remember? You WON'T tell, WILL you, -Joe?" And the poor creature dropped on his knees before the stolid -murderer, and clasped his appealing hands. - -"No, you've always been fair and square with me, Muff Potter, and I -won't go back on you. There, now, that's as fair as a man can say." - -"Oh, Joe, you're an angel. I'll bless you for this the longest day I -live." And Potter began to cry. - -"Come, now, that's enough of that. This ain't any time for blubbering. -You be off yonder way and I'll go this. Move, now, and don't leave any -tracks behind you." - -Potter started on a trot that quickly increased to a run. The -half-breed stood looking after him. He muttered: - -"If he's as much stunned with the lick and fuddled with the rum as he -had the look of being, he won't think of the knife till he's gone so -far he'll be afraid to come back after it to such a place by himself ---chicken-heart!" - -Two or three minutes later the murdered man, the blanketed corpse, the -lidless coffin, and the open grave were under no inspection but the -moon's. The stillness was complete again, too. - - - -CHAPTER X - -THE two boys flew on and on, toward the village, speechless with -horror. They glanced backward over their shoulders from time to time, -apprehensively, as if they feared they might be followed. Every stump -that started up in their path seemed a man and an enemy, and made them -catch their breath; and as they sped by some outlying cottages that lay -near the village, the barking of the aroused watch-dogs seemed to give -wings to their feet. - -"If we can only get to the old tannery before we break down!" -whispered Tom, in short catches between breaths. "I can't stand it much -longer." - -Huckleberry's hard pantings were his only reply, and the boys fixed -their eyes on the goal of their hopes and bent to their work to win it. -They gained steadily on it, and at last, breast to breast, they burst -through the open door and fell grateful and exhausted in the sheltering -shadows beyond. By and by their pulses slowed down, and Tom whispered: - -"Huckleberry, what do you reckon'll come of this?" - -"If Doctor Robinson dies, I reckon hanging'll come of it." - -"Do you though?" - -"Why, I KNOW it, Tom." - -Tom thought a while, then he said: - -"Who'll tell? We?" - -"What are you talking about? S'pose something happened and Injun Joe -DIDN'T hang? Why, he'd kill us some time or other, just as dead sure as -we're a laying here." - -"That's just what I was thinking to myself, Huck." - -"If anybody tells, let Muff Potter do it, if he's fool enough. He's -generally drunk enough." - -Tom said nothing--went on thinking. Presently he whispered: - -"Huck, Muff Potter don't know it. How can he tell?" - -"What's the reason he don't know it?" - -"Because he'd just got that whack when Injun Joe done it. D'you reckon -he could see anything? D'you reckon he knowed anything?" - -"By hokey, that's so, Tom!" - -"And besides, look-a-here--maybe that whack done for HIM!" - -"No, 'taint likely, Tom. He had liquor in him; I could see that; and -besides, he always has. Well, when pap's full, you might take and belt -him over the head with a church and you couldn't phase him. He says so, -his own self. So it's the same with Muff Potter, of course. But if a -man was dead sober, I reckon maybe that whack might fetch him; I dono." - -After another reflective silence, Tom said: - -"Hucky, you sure you can keep mum?" - -"Tom, we GOT to keep mum. You know that. That Injun devil wouldn't -make any more of drownding us than a couple of cats, if we was to -squeak 'bout this and they didn't hang him. Now, look-a-here, Tom, less -take and swear to one another--that's what we got to do--swear to keep -mum." - -"I'm agreed. It's the best thing. Would you just hold hands and swear -that we--" - -"Oh no, that wouldn't do for this. That's good enough for little -rubbishy common things--specially with gals, cuz THEY go back on you -anyway, and blab if they get in a huff--but there orter be writing -'bout a big thing like this. And blood." - -Tom's whole being applauded this idea. It was deep, and dark, and -awful; the hour, the circumstances, the surroundings, were in keeping -with it. He picked up a clean pine shingle that lay in the moonlight, -took a little fragment of "red keel" out of his pocket, got the moon on -his work, and painfully scrawled these lines, emphasizing each slow -down-stroke by clamping his tongue between his teeth, and letting up -the pressure on the up-strokes. [See next page.] - - "Huck Finn and - Tom Sawyer swears - they will keep mum - about This and They - wish They may Drop - down dead in Their - Tracks if They ever - Tell and Rot." - -Huckleberry was filled with admiration of Tom's facility in writing, -and the sublimity of his language. He at once took a pin from his lapel -and was going to prick his flesh, but Tom said: - -"Hold on! Don't do that. A pin's brass. It might have verdigrease on -it." - -"What's verdigrease?" - -"It's p'ison. That's what it is. You just swaller some of it once ---you'll see." - -So Tom unwound the thread from one of his needles, and each boy -pricked the ball of his thumb and squeezed out a drop of blood. In -time, after many squeezes, Tom managed to sign his initials, using the -ball of his little finger for a pen. Then he showed Huckleberry how to -make an H and an F, and the oath was complete. They buried the shingle -close to the wall, with some dismal ceremonies and incantations, and -the fetters that bound their tongues were considered to be locked and -the key thrown away. - -A figure crept stealthily through a break in the other end of the -ruined building, now, but they did not notice it. - -"Tom," whispered Huckleberry, "does this keep us from EVER telling ---ALWAYS?" - -"Of course it does. It don't make any difference WHAT happens, we got -to keep mum. We'd drop down dead--don't YOU know that?" - -"Yes, I reckon that's so." - -They continued to whisper for some little time. Presently a dog set up -a long, lugubrious howl just outside--within ten feet of them. The boys -clasped each other suddenly, in an agony of fright. - -"Which of us does he mean?" gasped Huckleberry. - -"I dono--peep through the crack. Quick!" - -"No, YOU, Tom!" - -"I can't--I can't DO it, Huck!" - -"Please, Tom. There 'tis again!" - -"Oh, lordy, I'm thankful!" whispered Tom. "I know his voice. It's Bull -Harbison." * - -[* If Mr. Harbison owned a slave named Bull, Tom would have spoken of -him as "Harbison's Bull," but a son or a dog of that name was "Bull -Harbison."] - -"Oh, that's good--I tell you, Tom, I was most scared to death; I'd a -bet anything it was a STRAY dog." - -The dog howled again. The boys' hearts sank once more. - -"Oh, my! that ain't no Bull Harbison!" whispered Huckleberry. "DO, Tom!" - -Tom, quaking with fear, yielded, and put his eye to the crack. His -whisper was hardly audible when he said: - -"Oh, Huck, IT S A STRAY DOG!" - -"Quick, Tom, quick! Who does he mean?" - -"Huck, he must mean us both--we're right together." - -"Oh, Tom, I reckon we're goners. I reckon there ain't no mistake 'bout -where I'LL go to. I been so wicked." - -"Dad fetch it! This comes of playing hookey and doing everything a -feller's told NOT to do. I might a been good, like Sid, if I'd a tried ---but no, I wouldn't, of course. But if ever I get off this time, I lay -I'll just WALLER in Sunday-schools!" And Tom began to snuffle a little. - -"YOU bad!" and Huckleberry began to snuffle too. "Consound it, Tom -Sawyer, you're just old pie, 'longside o' what I am. Oh, LORDY, lordy, -lordy, I wisht I only had half your chance." - -Tom choked off and whispered: - -"Look, Hucky, look! He's got his BACK to us!" - -Hucky looked, with joy in his heart. - -"Well, he has, by jingoes! Did he before?" - -"Yes, he did. But I, like a fool, never thought. Oh, this is bully, -you know. NOW who can he mean?" - -The howling stopped. Tom pricked up his ears. - -"Sh! What's that?" he whispered. - -"Sounds like--like hogs grunting. No--it's somebody snoring, Tom." - -"That IS it! Where 'bouts is it, Huck?" - -"I bleeve it's down at 'tother end. Sounds so, anyway. Pap used to -sleep there, sometimes, 'long with the hogs, but laws bless you, he -just lifts things when HE snores. Besides, I reckon he ain't ever -coming back to this town any more." - -The spirit of adventure rose in the boys' souls once more. - -"Hucky, do you das't to go if I lead?" - -"I don't like to, much. Tom, s'pose it's Injun Joe!" - -Tom quailed. But presently the temptation rose up strong again and the -boys agreed to try, with the understanding that they would take to -their heels if the snoring stopped. So they went tiptoeing stealthily -down, the one behind the other. When they had got to within five steps -of the snorer, Tom stepped on a stick, and it broke with a sharp snap. -The man moaned, writhed a little, and his face came into the moonlight. -It was Muff Potter. The boys' hearts had stood still, and their hopes -too, when the man moved, but their fears passed away now. They tiptoed -out, through the broken weather-boarding, and stopped at a little -distance to exchange a parting word. That long, lugubrious howl rose on -the night air again! They turned and saw the strange dog standing -within a few feet of where Potter was lying, and FACING Potter, with -his nose pointing heavenward. - -"Oh, geeminy, it's HIM!" exclaimed both boys, in a breath. - -"Say, Tom--they say a stray dog come howling around Johnny Miller's -house, 'bout midnight, as much as two weeks ago; and a whippoorwill -come in and lit on the banisters and sung, the very same evening; and -there ain't anybody dead there yet." - -"Well, I know that. And suppose there ain't. Didn't Gracie Miller fall -in the kitchen fire and burn herself terrible the very next Saturday?" - -"Yes, but she ain't DEAD. And what's more, she's getting better, too." - -"All right, you wait and see. She's a goner, just as dead sure as Muff -Potter's a goner. That's what the niggers say, and they know all about -these kind of things, Huck." - -Then they separated, cogitating. When Tom crept in at his bedroom -window the night was almost spent. He undressed with excessive caution, -and fell asleep congratulating himself that nobody knew of his -escapade. He was not aware that the gently-snoring Sid was awake, and -had been so for an hour. - -When Tom awoke, Sid was dressed and gone. There was a late look in the -light, a late sense in the atmosphere. He was startled. Why had he not -been called--persecuted till he was up, as usual? The thought filled -him with bodings. Within five minutes he was dressed and down-stairs, -feeling sore and drowsy. The family were still at table, but they had -finished breakfast. There was no voice of rebuke; but there were -averted eyes; there was a silence and an air of solemnity that struck a -chill to the culprit's heart. He sat down and tried to seem gay, but it -was up-hill work; it roused no smile, no response, and he lapsed into -silence and let his heart sink down to the depths. - -After breakfast his aunt took him aside, and Tom almost brightened in -the hope that he was going to be flogged; but it was not so. His aunt -wept over him and asked him how he could go and break her old heart so; -and finally told him to go on, and ruin himself and bring her gray -hairs with sorrow to the grave, for it was no use for her to try any -more. This was worse than a thousand whippings, and Tom's heart was -sorer now than his body. He cried, he pleaded for forgiveness, promised -to reform over and over again, and then received his dismissal, feeling -that he had won but an imperfect forgiveness and established but a -feeble confidence. - -He left the presence too miserable to even feel revengeful toward Sid; -and so the latter's prompt retreat through the back gate was -unnecessary. He moped to school gloomy and sad, and took his flogging, -along with Joe Harper, for playing hookey the day before, with the air -of one whose heart was busy with heavier woes and wholly dead to -trifles. Then he betook himself to his seat, rested his elbows on his -desk and his jaws in his hands, and stared at the wall with the stony -stare of suffering that has reached the limit and can no further go. -His elbow was pressing against some hard substance. After a long time -he slowly and sadly changed his position, and took up this object with -a sigh. It was in a paper. He unrolled it. A long, lingering, colossal -sigh followed, and his heart broke. It was his brass andiron knob! - -This final feather broke the camel's back. - - - -CHAPTER XI - -CLOSE upon the hour of noon the whole village was suddenly electrified -with the ghastly news. No need of the as yet undreamed-of telegraph; -the tale flew from man to man, from group to group, from house to -house, with little less than telegraphic speed. Of course the -schoolmaster gave holiday for that afternoon; the town would have -thought strangely of him if he had not. - -A gory knife had been found close to the murdered man, and it had been -recognized by somebody as belonging to Muff Potter--so the story ran. -And it was said that a belated citizen had come upon Potter washing -himself in the "branch" about one or two o'clock in the morning, and -that Potter had at once sneaked off--suspicious circumstances, -especially the washing which was not a habit with Potter. It was also -said that the town had been ransacked for this "murderer" (the public -are not slow in the matter of sifting evidence and arriving at a -verdict), but that he could not be found. Horsemen had departed down -all the roads in every direction, and the Sheriff "was confident" that -he would be captured before night. - -All the town was drifting toward the graveyard. Tom's heartbreak -vanished and he joined the procession, not because he would not a -thousand times rather go anywhere else, but because an awful, -unaccountable fascination drew him on. Arrived at the dreadful place, -he wormed his small body through the crowd and saw the dismal -spectacle. It seemed to him an age since he was there before. Somebody -pinched his arm. He turned, and his eyes met Huckleberry's. Then both -looked elsewhere at once, and wondered if anybody had noticed anything -in their mutual glance. But everybody was talking, and intent upon the -grisly spectacle before them. - -"Poor fellow!" "Poor young fellow!" "This ought to be a lesson to -grave robbers!" "Muff Potter'll hang for this if they catch him!" This -was the drift of remark; and the minister said, "It was a judgment; His -hand is here." - -Now Tom shivered from head to heel; for his eye fell upon the stolid -face of Injun Joe. At this moment the crowd began to sway and struggle, -and voices shouted, "It's him! it's him! he's coming himself!" - -"Who? Who?" from twenty voices. - -"Muff Potter!" - -"Hallo, he's stopped!--Look out, he's turning! Don't let him get away!" - -People in the branches of the trees over Tom's head said he wasn't -trying to get away--he only looked doubtful and perplexed. - -"Infernal impudence!" said a bystander; "wanted to come and take a -quiet look at his work, I reckon--didn't expect any company." - -The crowd fell apart, now, and the Sheriff came through, -ostentatiously leading Potter by the arm. The poor fellow's face was -haggard, and his eyes showed the fear that was upon him. When he stood -before the murdered man, he shook as with a palsy, and he put his face -in his hands and burst into tears. - -"I didn't do it, friends," he sobbed; "'pon my word and honor I never -done it." - -"Who's accused you?" shouted a voice. - -This shot seemed to carry home. Potter lifted his face and looked -around him with a pathetic hopelessness in his eyes. He saw Injun Joe, -and exclaimed: - -"Oh, Injun Joe, you promised me you'd never--" - -"Is that your knife?" and it was thrust before him by the Sheriff. - -Potter would have fallen if they had not caught him and eased him to -the ground. Then he said: - -"Something told me 't if I didn't come back and get--" He shuddered; -then waved his nerveless hand with a vanquished gesture and said, "Tell -'em, Joe, tell 'em--it ain't any use any more." - -Then Huckleberry and Tom stood dumb and staring, and heard the -stony-hearted liar reel off his serene statement, they expecting every -moment that the clear sky would deliver God's lightnings upon his head, -and wondering to see how long the stroke was delayed. And when he had -finished and still stood alive and whole, their wavering impulse to -break their oath and save the poor betrayed prisoner's life faded and -vanished away, for plainly this miscreant had sold himself to Satan and -it would be fatal to meddle with the property of such a power as that. - -"Why didn't you leave? What did you want to come here for?" somebody -said. - -"I couldn't help it--I couldn't help it," Potter moaned. "I wanted to -run away, but I couldn't seem to come anywhere but here." And he fell -to sobbing again. - -Injun Joe repeated his statement, just as calmly, a few minutes -afterward on the inquest, under oath; and the boys, seeing that the -lightnings were still withheld, were confirmed in their belief that Joe -had sold himself to the devil. He was now become, to them, the most -balefully interesting object they had ever looked upon, and they could -not take their fascinated eyes from his face. - -They inwardly resolved to watch him nights, when opportunity should -offer, in the hope of getting a glimpse of his dread master. - -Injun Joe helped to raise the body of the murdered man and put it in a -wagon for removal; and it was whispered through the shuddering crowd -that the wound bled a little! The boys thought that this happy -circumstance would turn suspicion in the right direction; but they were -disappointed, for more than one villager remarked: - -"It was within three feet of Muff Potter when it done it." - -Tom's fearful secret and gnawing conscience disturbed his sleep for as -much as a week after this; and at breakfast one morning Sid said: - -"Tom, you pitch around and talk in your sleep so much that you keep me -awake half the time." - -Tom blanched and dropped his eyes. - -"It's a bad sign," said Aunt Polly, gravely. "What you got on your -mind, Tom?" - -"Nothing. Nothing 't I know of." But the boy's hand shook so that he -spilled his coffee. - -"And you do talk such stuff," Sid said. "Last night you said, 'It's -blood, it's blood, that's what it is!' You said that over and over. And -you said, 'Don't torment me so--I'll tell!' Tell WHAT? What is it -you'll tell?" - -Everything was swimming before Tom. There is no telling what might -have happened, now, but luckily the concern passed out of Aunt Polly's -face and she came to Tom's relief without knowing it. She said: - -"Sho! It's that dreadful murder. I dream about it most every night -myself. Sometimes I dream it's me that done it." - -Mary said she had been affected much the same way. Sid seemed -satisfied. Tom got out of the presence as quick as he plausibly could, -and after that he complained of toothache for a week, and tied up his -jaws every night. He never knew that Sid lay nightly watching, and -frequently slipped the bandage free and then leaned on his elbow -listening a good while at a time, and afterward slipped the bandage -back to its place again. Tom's distress of mind wore off gradually and -the toothache grew irksome and was discarded. If Sid really managed to -make anything out of Tom's disjointed mutterings, he kept it to himself. - -It seemed to Tom that his schoolmates never would get done holding -inquests on dead cats, and thus keeping his trouble present to his -mind. Sid noticed that Tom never was coroner at one of these inquiries, -though it had been his habit to take the lead in all new enterprises; -he noticed, too, that Tom never acted as a witness--and that was -strange; and Sid did not overlook the fact that Tom even showed a -marked aversion to these inquests, and always avoided them when he -could. Sid marvelled, but said nothing. However, even inquests went out -of vogue at last, and ceased to torture Tom's conscience. - -Every day or two, during this time of sorrow, Tom watched his -opportunity and went to the little grated jail-window and smuggled such -small comforts through to the "murderer" as he could get hold of. The -jail was a trifling little brick den that stood in a marsh at the edge -of the village, and no guards were afforded for it; indeed, it was -seldom occupied. These offerings greatly helped to ease Tom's -conscience. - -The villagers had a strong desire to tar-and-feather Injun Joe and -ride him on a rail, for body-snatching, but so formidable was his -character that nobody could be found who was willing to take the lead -in the matter, so it was dropped. He had been careful to begin both of -his inquest-statements with the fight, without confessing the -grave-robbery that preceded it; therefore it was deemed wisest not -to try the case in the courts at present. - - - -CHAPTER XII - -ONE of the reasons why Tom's mind had drifted away from its secret -troubles was, that it had found a new and weighty matter to interest -itself about. Becky Thatcher had stopped coming to school. Tom had -struggled with his pride a few days, and tried to "whistle her down the -wind," but failed. He began to find himself hanging around her father's -house, nights, and feeling very miserable. She was ill. What if she -should die! There was distraction in the thought. He no longer took an -interest in war, nor even in piracy. The charm of life was gone; there -was nothing but dreariness left. He put his hoop away, and his bat; -there was no joy in them any more. His aunt was concerned. She began to -try all manner of remedies on him. She was one of those people who are -infatuated with patent medicines and all new-fangled methods of -producing health or mending it. She was an inveterate experimenter in -these things. When something fresh in this line came out she was in a -fever, right away, to try it; not on herself, for she was never ailing, -but on anybody else that came handy. She was a subscriber for all the -"Health" periodicals and phrenological frauds; and the solemn ignorance -they were inflated with was breath to her nostrils. All the "rot" they -contained about ventilation, and how to go to bed, and how to get up, -and what to eat, and what to drink, and how much exercise to take, and -what frame of mind to keep one's self in, and what sort of clothing to -wear, was all gospel to her, and she never observed that her -health-journals of the current month customarily upset everything they -had recommended the month before. She was as simple-hearted and honest -as the day was long, and so she was an easy victim. She gathered -together her quack periodicals and her quack medicines, and thus armed -with death, went about on her pale horse, metaphorically speaking, with -"hell following after." But she never suspected that she was not an -angel of healing and the balm of Gilead in disguise, to the suffering -neighbors. - -The water treatment was new, now, and Tom's low condition was a -windfall to her. She had him out at daylight every morning, stood him -up in the woodshed and drowned him with a deluge of cold water; then -she scrubbed him down with a towel like a file, and so brought him to; -then she rolled him up in a wet sheet and put him away under blankets -till she sweated his soul clean and "the yellow stains of it came -through his pores"--as Tom said. - -Yet notwithstanding all this, the boy grew more and more melancholy -and pale and dejected. She added hot baths, sitz baths, shower baths, -and plunges. The boy remained as dismal as a hearse. She began to -assist the water with a slim oatmeal diet and blister-plasters. She -calculated his capacity as she would a jug's, and filled him up every -day with quack cure-alls. - -Tom had become indifferent to persecution by this time. This phase -filled the old lady's heart with consternation. This indifference must -be broken up at any cost. Now she heard of Pain-killer for the first -time. She ordered a lot at once. She tasted it and was filled with -gratitude. It was simply fire in a liquid form. She dropped the water -treatment and everything else, and pinned her faith to Pain-killer. She -gave Tom a teaspoonful and watched with the deepest anxiety for the -result. Her troubles were instantly at rest, her soul at peace again; -for the "indifference" was broken up. The boy could not have shown a -wilder, heartier interest, if she had built a fire under him. - -Tom felt that it was time to wake up; this sort of life might be -romantic enough, in his blighted condition, but it was getting to have -too little sentiment and too much distracting variety about it. So he -thought over various plans for relief, and finally hit pon that of -professing to be fond of Pain-killer. He asked for it so often that he -became a nuisance, and his aunt ended by telling him to help himself -and quit bothering her. If it had been Sid, she would have had no -misgivings to alloy her delight; but since it was Tom, she watched the -bottle clandestinely. She found that the medicine did really diminish, -but it did not occur to her that the boy was mending the health of a -crack in the sitting-room floor with it. - -One day Tom was in the act of dosing the crack when his aunt's yellow -cat came along, purring, eying the teaspoon avariciously, and begging -for a taste. Tom said: - -"Don't ask for it unless you want it, Peter." - -But Peter signified that he did want it. - -"You better make sure." - -Peter was sure. - -"Now you've asked for it, and I'll give it to you, because there ain't -anything mean about me; but if you find you don't like it, you mustn't -blame anybody but your own self." - -Peter was agreeable. So Tom pried his mouth open and poured down the -Pain-killer. Peter sprang a couple of yards in the air, and then -delivered a war-whoop and set off round and round the room, banging -against furniture, upsetting flower-pots, and making general havoc. -Next he rose on his hind feet and pranced around, in a frenzy of -enjoyment, with his head over his shoulder and his voice proclaiming -his unappeasable happiness. Then he went tearing around the house again -spreading chaos and destruction in his path. Aunt Polly entered in time -to see him throw a few double summersets, deliver a final mighty -hurrah, and sail through the open window, carrying the rest of the -flower-pots with him. The old lady stood petrified with astonishment, -peering over her glasses; Tom lay on the floor expiring with laughter. - -"Tom, what on earth ails that cat?" - -"I don't know, aunt," gasped the boy. - -"Why, I never see anything like it. What did make him act so?" - -"Deed I don't know, Aunt Polly; cats always act so when they're having -a good time." - -"They do, do they?" There was something in the tone that made Tom -apprehensive. - -"Yes'm. That is, I believe they do." - -"You DO?" - -"Yes'm." - -The old lady was bending down, Tom watching, with interest emphasized -by anxiety. Too late he divined her "drift." The handle of the telltale -teaspoon was visible under the bed-valance. Aunt Polly took it, held it -up. Tom winced, and dropped his eyes. Aunt Polly raised him by the -usual handle--his ear--and cracked his head soundly with her thimble. - -"Now, sir, what did you want to treat that poor dumb beast so, for?" - -"I done it out of pity for him--because he hadn't any aunt." - -"Hadn't any aunt!--you numskull. What has that got to do with it?" - -"Heaps. Because if he'd had one she'd a burnt him out herself! She'd a -roasted his bowels out of him 'thout any more feeling than if he was a -human!" - -Aunt Polly felt a sudden pang of remorse. This was putting the thing -in a new light; what was cruelty to a cat MIGHT be cruelty to a boy, -too. She began to soften; she felt sorry. Her eyes watered a little, -and she put her hand on Tom's head and said gently: - -"I was meaning for the best, Tom. And, Tom, it DID do you good." - -Tom looked up in her face with just a perceptible twinkle peeping -through his gravity. - -"I know you was meaning for the best, aunty, and so was I with Peter. -It done HIM good, too. I never see him get around so since--" - -"Oh, go 'long with you, Tom, before you aggravate me again. And you -try and see if you can't be a good boy, for once, and you needn't take -any more medicine." - -Tom reached school ahead of time. It was noticed that this strange -thing had been occurring every day latterly. And now, as usual of late, -he hung about the gate of the schoolyard instead of playing with his -comrades. He was sick, he said, and he looked it. He tried to seem to -be looking everywhere but whither he really was looking--down the road. -Presently Jeff Thatcher hove in sight, and Tom's face lighted; he gazed -a moment, and then turned sorrowfully away. When Jeff arrived, Tom -accosted him; and "led up" warily to opportunities for remark about -Becky, but the giddy lad never could see the bait. Tom watched and -watched, hoping whenever a frisking frock came in sight, and hating the -owner of it as soon as he saw she was not the right one. At last frocks -ceased to appear, and he dropped hopelessly into the dumps; he entered -the empty schoolhouse and sat down to suffer. Then one more frock -passed in at the gate, and Tom's heart gave a great bound. The next -instant he was out, and "going on" like an Indian; yelling, laughing, -chasing boys, jumping over the fence at risk of life and limb, throwing -handsprings, standing on his head--doing all the heroic things he could -conceive of, and keeping a furtive eye out, all the while, to see if -Becky Thatcher was noticing. But she seemed to be unconscious of it -all; she never looked. Could it be possible that she was not aware that -he was there? He carried his exploits to her immediate vicinity; came -war-whooping around, snatched a boy's cap, hurled it to the roof of the -schoolhouse, broke through a group of boys, tumbling them in every -direction, and fell sprawling, himself, under Becky's nose, almost -upsetting her--and she turned, with her nose in the air, and he heard -her say: "Mf! some people think they're mighty smart--always showing -off!" - -Tom's cheeks burned. He gathered himself up and sneaked off, crushed -and crestfallen. - - - -CHAPTER XIII - -TOM'S mind was made up now. He was gloomy and desperate. He was a -forsaken, friendless boy, he said; nobody loved him; when they found -out what they had driven him to, perhaps they would be sorry; he had -tried to do right and get along, but they would not let him; since -nothing would do them but to be rid of him, let it be so; and let them -blame HIM for the consequences--why shouldn't they? What right had the -friendless to complain? Yes, they had forced him to it at last: he -would lead a life of crime. There was no choice. - -By this time he was far down Meadow Lane, and the bell for school to -"take up" tinkled faintly upon his ear. He sobbed, now, to think he -should never, never hear that old familiar sound any more--it was very -hard, but it was forced on him; since he was driven out into the cold -world, he must submit--but he forgave them. Then the sobs came thick -and fast. - -Just at this point he met his soul's sworn comrade, Joe Harper ---hard-eyed, and with evidently a great and dismal purpose in his heart. -Plainly here were "two souls with but a single thought." Tom, wiping -his eyes with his sleeve, began to blubber out something about a -resolution to escape from hard usage and lack of sympathy at home by -roaming abroad into the great world never to return; and ended by -hoping that Joe would not forget him. - -But it transpired that this was a request which Joe had just been -going to make of Tom, and had come to hunt him up for that purpose. His -mother had whipped him for drinking some cream which he had never -tasted and knew nothing about; it was plain that she was tired of him -and wished him to go; if she felt that way, there was nothing for him -to do but succumb; he hoped she would be happy, and never regret having -driven her poor boy out into the unfeeling world to suffer and die. - -As the two boys walked sorrowing along, they made a new compact to -stand by each other and be brothers and never separate till death -relieved them of their troubles. Then they began to lay their plans. -Joe was for being a hermit, and living on crusts in a remote cave, and -dying, some time, of cold and want and grief; but after listening to -Tom, he conceded that there were some conspicuous advantages about a -life of crime, and so he consented to be a pirate. - -Three miles below St. Petersburg, at a point where the Mississippi -River was a trifle over a mile wide, there was a long, narrow, wooded -island, with a shallow bar at the head of it, and this offered well as -a rendezvous. It was not inhabited; it lay far over toward the further -shore, abreast a dense and almost wholly unpeopled forest. So Jackson's -Island was chosen. Who were to be the subjects of their piracies was a -matter that did not occur to them. Then they hunted up Huckleberry -Finn, and he joined them promptly, for all careers were one to him; he -was indifferent. They presently separated to meet at a lonely spot on -the river-bank two miles above the village at the favorite hour--which -was midnight. There was a small log raft there which they meant to -capture. Each would bring hooks and lines, and such provision as he -could steal in the most dark and mysterious way--as became outlaws. And -before the afternoon was done, they had all managed to enjoy the sweet -glory of spreading the fact that pretty soon the town would "hear -something." All who got this vague hint were cautioned to "be mum and -wait." - -About midnight Tom arrived with a boiled ham and a few trifles, -and stopped in a dense undergrowth on a small bluff overlooking the -meeting-place. It was starlight, and very still. The mighty river lay -like an ocean at rest. Tom listened a moment, but no sound disturbed the -quiet. Then he gave a low, distinct whistle. It was answered from under -the bluff. Tom whistled twice more; these signals were answered in the -same way. Then a guarded voice said: - -"Who goes there?" - -"Tom Sawyer, the Black Avenger of the Spanish Main. Name your names." - -"Huck Finn the Red-Handed, and Joe Harper the Terror of the Seas." Tom -had furnished these titles, from his favorite literature. - -"'Tis well. Give the countersign." - -Two hoarse whispers delivered the same awful word simultaneously to -the brooding night: - -"BLOOD!" - -Then Tom tumbled his ham over the bluff and let himself down after it, -tearing both skin and clothes to some extent in the effort. There was -an easy, comfortable path along the shore under the bluff, but it -lacked the advantages of difficulty and danger so valued by a pirate. - -The Terror of the Seas had brought a side of bacon, and had about worn -himself out with getting it there. Finn the Red-Handed had stolen a -skillet and a quantity of half-cured leaf tobacco, and had also brought -a few corn-cobs to make pipes with. But none of the pirates smoked or -"chewed" but himself. The Black Avenger of the Spanish Main said it -would never do to start without some fire. That was a wise thought; -matches were hardly known there in that day. They saw a fire -smouldering upon a great raft a hundred yards above, and they went -stealthily thither and helped themselves to a chunk. They made an -imposing adventure of it, saying, "Hist!" every now and then, and -suddenly halting with finger on lip; moving with hands on imaginary -dagger-hilts; and giving orders in dismal whispers that if "the foe" -stirred, to "let him have it to the hilt," because "dead men tell no -tales." They knew well enough that the raftsmen were all down at the -village laying in stores or having a spree, but still that was no -excuse for their conducting this thing in an unpiratical way. - -They shoved off, presently, Tom in command, Huck at the after oar and -Joe at the forward. Tom stood amidships, gloomy-browed, and with folded -arms, and gave his orders in a low, stern whisper: - -"Luff, and bring her to the wind!" - -"Aye-aye, sir!" - -"Steady, steady-y-y-y!" - -"Steady it is, sir!" - -"Let her go off a point!" - -"Point it is, sir!" - -As the boys steadily and monotonously drove the raft toward mid-stream -it was no doubt understood that these orders were given only for -"style," and were not intended to mean anything in particular. - -"What sail's she carrying?" - -"Courses, tops'ls, and flying-jib, sir." - -"Send the r'yals up! Lay out aloft, there, half a dozen of ye ---foretopmaststuns'l! Lively, now!" - -"Aye-aye, sir!" - -"Shake out that maintogalans'l! Sheets and braces! NOW my hearties!" - -"Aye-aye, sir!" - -"Hellum-a-lee--hard a port! Stand by to meet her when she comes! Port, -port! NOW, men! With a will! Stead-y-y-y!" - -"Steady it is, sir!" - -The raft drew beyond the middle of the river; the boys pointed her -head right, and then lay on their oars. The river was not high, so -there was not more than a two or three mile current. Hardly a word was -said during the next three-quarters of an hour. Now the raft was -passing before the distant town. Two or three glimmering lights showed -where it lay, peacefully sleeping, beyond the vague vast sweep of -star-gemmed water, unconscious of the tremendous event that was happening. -The Black Avenger stood still with folded arms, "looking his last" upon -the scene of his former joys and his later sufferings, and wishing -"she" could see him now, abroad on the wild sea, facing peril and death -with dauntless heart, going to his doom with a grim smile on his lips. -It was but a small strain on his imagination to remove Jackson's Island -beyond eyeshot of the village, and so he "looked his last" with a -broken and satisfied heart. The other pirates were looking their last, -too; and they all looked so long that they came near letting the -current drift them out of the range of the island. But they discovered -the danger in time, and made shift to avert it. About two o'clock in -the morning the raft grounded on the bar two hundred yards above the -head of the island, and they waded back and forth until they had landed -their freight. Part of the little raft's belongings consisted of an old -sail, and this they spread over a nook in the bushes for a tent to -shelter their provisions; but they themselves would sleep in the open -air in good weather, as became outlaws. - -They built a fire against the side of a great log twenty or thirty -steps within the sombre depths of the forest, and then cooked some -bacon in the frying-pan for supper, and used up half of the corn "pone" -stock they had brought. It seemed glorious sport to be feasting in that -wild, free way in the virgin forest of an unexplored and uninhabited -island, far from the haunts of men, and they said they never would -return to civilization. The climbing fire lit up their faces and threw -its ruddy glare upon the pillared tree-trunks of their forest temple, -and upon the varnished foliage and festooning vines. - -When the last crisp slice of bacon was gone, and the last allowance of -corn pone devoured, the boys stretched themselves out on the grass, -filled with contentment. They could have found a cooler place, but they -would not deny themselves such a romantic feature as the roasting -camp-fire. - -"AIN'T it gay?" said Joe. - -"It's NUTS!" said Tom. "What would the boys say if they could see us?" - -"Say? Well, they'd just die to be here--hey, Hucky!" - -"I reckon so," said Huckleberry; "anyways, I'm suited. I don't want -nothing better'n this. I don't ever get enough to eat, gen'ally--and -here they can't come and pick at a feller and bullyrag him so." - -"It's just the life for me," said Tom. "You don't have to get up, -mornings, and you don't have to go to school, and wash, and all that -blame foolishness. You see a pirate don't have to do ANYTHING, Joe, -when he's ashore, but a hermit HE has to be praying considerable, and -then he don't have any fun, anyway, all by himself that way." - -"Oh yes, that's so," said Joe, "but I hadn't thought much about it, -you know. I'd a good deal rather be a pirate, now that I've tried it." - -"You see," said Tom, "people don't go much on hermits, nowadays, like -they used to in old times, but a pirate's always respected. And a -hermit's got to sleep on the hardest place he can find, and put -sackcloth and ashes on his head, and stand out in the rain, and--" - -"What does he put sackcloth and ashes on his head for?" inquired Huck. - -"I dono. But they've GOT to do it. Hermits always do. You'd have to do -that if you was a hermit." - -"Dern'd if I would," said Huck. - -"Well, what would you do?" - -"I dono. But I wouldn't do that." - -"Why, Huck, you'd HAVE to. How'd you get around it?" - -"Why, I just wouldn't stand it. I'd run away." - -"Run away! Well, you WOULD be a nice old slouch of a hermit. You'd be -a disgrace." - -The Red-Handed made no response, being better employed. He had -finished gouging out a cob, and now he fitted a weed stem to it, loaded -it with tobacco, and was pressing a coal to the charge and blowing a -cloud of fragrant smoke--he was in the full bloom of luxurious -contentment. The other pirates envied him this majestic vice, and -secretly resolved to acquire it shortly. Presently Huck said: - -"What does pirates have to do?" - -Tom said: - -"Oh, they have just a bully time--take ships and burn them, and get -the money and bury it in awful places in their island where there's -ghosts and things to watch it, and kill everybody in the ships--make -'em walk a plank." - -"And they carry the women to the island," said Joe; "they don't kill -the women." - -"No," assented Tom, "they don't kill the women--they're too noble. And -the women's always beautiful, too. - -"And don't they wear the bulliest clothes! Oh no! All gold and silver -and di'monds," said Joe, with enthusiasm. - -"Who?" said Huck. - -"Why, the pirates." - -Huck scanned his own clothing forlornly. - -"I reckon I ain't dressed fitten for a pirate," said he, with a -regretful pathos in his voice; "but I ain't got none but these." - -But the other boys told him the fine clothes would come fast enough, -after they should have begun their adventures. They made him understand -that his poor rags would do to begin with, though it was customary for -wealthy pirates to start with a proper wardrobe. - -Gradually their talk died out and drowsiness began to steal upon the -eyelids of the little waifs. The pipe dropped from the fingers of the -Red-Handed, and he slept the sleep of the conscience-free and the -weary. The Terror of the Seas and the Black Avenger of the Spanish Main -had more difficulty in getting to sleep. They said their prayers -inwardly, and lying down, since there was nobody there with authority -to make them kneel and recite aloud; in truth, they had a mind not to -say them at all, but they were afraid to proceed to such lengths as -that, lest they might call down a sudden and special thunderbolt from -heaven. Then at once they reached and hovered upon the imminent verge -of sleep--but an intruder came, now, that would not "down." It was -conscience. They began to feel a vague fear that they had been doing -wrong to run away; and next they thought of the stolen meat, and then -the real torture came. They tried to argue it away by reminding -conscience that they had purloined sweetmeats and apples scores of -times; but conscience was not to be appeased by such thin -plausibilities; it seemed to them, in the end, that there was no -getting around the stubborn fact that taking sweetmeats was only -"hooking," while taking bacon and hams and such valuables was plain -simple stealing--and there was a command against that in the Bible. So -they inwardly resolved that so long as they remained in the business, -their piracies should not again be sullied with the crime of stealing. -Then conscience granted a truce, and these curiously inconsistent -pirates fell peacefully to sleep. - - - -CHAPTER XIV - -WHEN Tom awoke in the morning, he wondered where he was. He sat up and -rubbed his eyes and looked around. Then he comprehended. It was the -cool gray dawn, and there was a delicious sense of repose and peace in -the deep pervading calm and silence of the woods. Not a leaf stirred; -not a sound obtruded upon great Nature's meditation. Beaded dewdrops -stood upon the leaves and grasses. A white layer of ashes covered the -fire, and a thin blue breath of smoke rose straight into the air. Joe -and Huck still slept. - -Now, far away in the woods a bird called; another answered; presently -the hammering of a woodpecker was heard. Gradually the cool dim gray of -the morning whitened, and as gradually sounds multiplied and life -manifested itself. The marvel of Nature shaking off sleep and going to -work unfolded itself to the musing boy. A little green worm came -crawling over a dewy leaf, lifting two-thirds of his body into the air -from time to time and "sniffing around," then proceeding again--for he -was measuring, Tom said; and when the worm approached him, of its own -accord, he sat as still as a stone, with his hopes rising and falling, -by turns, as the creature still came toward him or seemed inclined to -go elsewhere; and when at last it considered a painful moment with its -curved body in the air and then came decisively down upon Tom's leg and -began a journey over him, his whole heart was glad--for that meant that -he was going to have a new suit of clothes--without the shadow of a -doubt a gaudy piratical uniform. Now a procession of ants appeared, -from nowhere in particular, and went about their labors; one struggled -manfully by with a dead spider five times as big as itself in its arms, -and lugged it straight up a tree-trunk. A brown spotted lady-bug -climbed the dizzy height of a grass blade, and Tom bent down close to -it and said, "Lady-bug, lady-bug, fly away home, your house is on fire, -your children's alone," and she took wing and went off to see about it ---which did not surprise the boy, for he knew of old that this insect was -credulous about conflagrations, and he had practised upon its -simplicity more than once. A tumblebug came next, heaving sturdily at -its ball, and Tom touched the creature, to see it shut its legs against -its body and pretend to be dead. The birds were fairly rioting by this -time. A catbird, the Northern mocker, lit in a tree over Tom's head, -and trilled out her imitations of her neighbors in a rapture of -enjoyment; then a shrill jay swept down, a flash of blue flame, and -stopped on a twig almost within the boy's reach, cocked his head to one -side and eyed the strangers with a consuming curiosity; a gray squirrel -and a big fellow of the "fox" kind came skurrying along, sitting up at -intervals to inspect and chatter at the boys, for the wild things had -probably never seen a human being before and scarcely knew whether to -be afraid or not. All Nature was wide awake and stirring, now; long -lances of sunlight pierced down through the dense foliage far and near, -and a few butterflies came fluttering upon the scene. - -Tom stirred up the other pirates and they all clattered away with a -shout, and in a minute or two were stripped and chasing after and -tumbling over each other in the shallow limpid water of the white -sandbar. They felt no longing for the little village sleeping in the -distance beyond the majestic waste of water. A vagrant current or a -slight rise in the river had carried off their raft, but this only -gratified them, since its going was something like burning the bridge -between them and civilization. - -They came back to camp wonderfully refreshed, glad-hearted, and -ravenous; and they soon had the camp-fire blazing up again. Huck found -a spring of clear cold water close by, and the boys made cups of broad -oak or hickory leaves, and felt that water, sweetened with such a -wildwood charm as that, would be a good enough substitute for coffee. -While Joe was slicing bacon for breakfast, Tom and Huck asked him to -hold on a minute; they stepped to a promising nook in the river-bank -and threw in their lines; almost immediately they had reward. Joe had -not had time to get impatient before they were back again with some -handsome bass, a couple of sun-perch and a small catfish--provisions -enough for quite a family. They fried the fish with the bacon, and were -astonished; for no fish had ever seemed so delicious before. They did -not know that the quicker a fresh-water fish is on the fire after he is -caught the better he is; and they reflected little upon what a sauce -open-air sleeping, open-air exercise, bathing, and a large ingredient -of hunger make, too. - -They lay around in the shade, after breakfast, while Huck had a smoke, -and then went off through the woods on an exploring expedition. They -tramped gayly along, over decaying logs, through tangled underbrush, -among solemn monarchs of the forest, hung from their crowns to the -ground with a drooping regalia of grape-vines. Now and then they came -upon snug nooks carpeted with grass and jeweled with flowers. - -They found plenty of things to be delighted with, but nothing to be -astonished at. They discovered that the island was about three miles -long and a quarter of a mile wide, and that the shore it lay closest to -was only separated from it by a narrow channel hardly two hundred yards -wide. They took a swim about every hour, so it was close upon the -middle of the afternoon when they got back to camp. They were too -hungry to stop to fish, but they fared sumptuously upon cold ham, and -then threw themselves down in the shade to talk. But the talk soon -began to drag, and then died. The stillness, the solemnity that brooded -in the woods, and the sense of loneliness, began to tell upon the -spirits of the boys. They fell to thinking. A sort of undefined longing -crept upon them. This took dim shape, presently--it was budding -homesickness. Even Finn the Red-Handed was dreaming of his doorsteps -and empty hogsheads. But they were all ashamed of their weakness, and -none was brave enough to speak his thought. - -For some time, now, the boys had been dully conscious of a peculiar -sound in the distance, just as one sometimes is of the ticking of a -clock which he takes no distinct note of. But now this mysterious sound -became more pronounced, and forced a recognition. The boys started, -glanced at each other, and then each assumed a listening attitude. -There was a long silence, profound and unbroken; then a deep, sullen -boom came floating down out of the distance. - -"What is it!" exclaimed Joe, under his breath. - -"I wonder," said Tom in a whisper. - -"'Tain't thunder," said Huckleberry, in an awed tone, "becuz thunder--" - -"Hark!" said Tom. "Listen--don't talk." - -They waited a time that seemed an age, and then the same muffled boom -troubled the solemn hush. - -"Let's go and see." - -They sprang to their feet and hurried to the shore toward the town. -They parted the bushes on the bank and peered out over the water. The -little steam ferryboat was about a mile below the village, drifting -with the current. Her broad deck seemed crowded with people. There were -a great many skiffs rowing about or floating with the stream in the -neighborhood of the ferryboat, but the boys could not determine what -the men in them were doing. Presently a great jet of white smoke burst -from the ferryboat's side, and as it expanded and rose in a lazy cloud, -that same dull throb of sound was borne to the listeners again. - -"I know now!" exclaimed Tom; "somebody's drownded!" - -"That's it!" said Huck; "they done that last summer, when Bill Turner -got drownded; they shoot a cannon over the water, and that makes him -come up to the top. Yes, and they take loaves of bread and put -quicksilver in 'em and set 'em afloat, and wherever there's anybody -that's drownded, they'll float right there and stop." - -"Yes, I've heard about that," said Joe. "I wonder what makes the bread -do that." - -"Oh, it ain't the bread, so much," said Tom; "I reckon it's mostly -what they SAY over it before they start it out." - -"But they don't say anything over it," said Huck. "I've seen 'em and -they don't." - -"Well, that's funny," said Tom. "But maybe they say it to themselves. -Of COURSE they do. Anybody might know that." - -The other boys agreed that there was reason in what Tom said, because -an ignorant lump of bread, uninstructed by an incantation, could not be -expected to act very intelligently when set upon an errand of such -gravity. - -"By jings, I wish I was over there, now," said Joe. - -"I do too" said Huck "I'd give heaps to know who it is." - -The boys still listened and watched. Presently a revealing thought -flashed through Tom's mind, and he exclaimed: - -"Boys, I know who's drownded--it's us!" - -They felt like heroes in an instant. Here was a gorgeous triumph; they -were missed; they were mourned; hearts were breaking on their account; -tears were being shed; accusing memories of unkindness to these poor -lost lads were rising up, and unavailing regrets and remorse were being -indulged; and best of all, the departed were the talk of the whole -town, and the envy of all the boys, as far as this dazzling notoriety -was concerned. This was fine. It was worth while to be a pirate, after -all. - -As twilight drew on, the ferryboat went back to her accustomed -business and the skiffs disappeared. The pirates returned to camp. They -were jubilant with vanity over their new grandeur and the illustrious -trouble they were making. They caught fish, cooked supper and ate it, -and then fell to guessing at what the village was thinking and saying -about them; and the pictures they drew of the public distress on their -account were gratifying to look upon--from their point of view. But -when the shadows of night closed them in, they gradually ceased to -talk, and sat gazing into the fire, with their minds evidently -wandering elsewhere. The excitement was gone, now, and Tom and Joe -could not keep back thoughts of certain persons at home who were not -enjoying this fine frolic as much as they were. Misgivings came; they -grew troubled and unhappy; a sigh or two escaped, unawares. By and by -Joe timidly ventured upon a roundabout "feeler" as to how the others -might look upon a return to civilization--not right now, but-- - -Tom withered him with derision! Huck, being uncommitted as yet, joined -in with Tom, and the waverer quickly "explained," and was glad to get -out of the scrape with as little taint of chicken-hearted homesickness -clinging to his garments as he could. Mutiny was effectually laid to -rest for the moment. - -As the night deepened, Huck began to nod, and presently to snore. Joe -followed next. Tom lay upon his elbow motionless, for some time, -watching the two intently. At last he got up cautiously, on his knees, -and went searching among the grass and the flickering reflections flung -by the camp-fire. He picked up and inspected several large -semi-cylinders of the thin white bark of a sycamore, and finally chose -two which seemed to suit him. Then he knelt by the fire and painfully -wrote something upon each of these with his "red keel"; one he rolled up -and put in his jacket pocket, and the other he put in Joe's hat and -removed it to a little distance from the owner. And he also put into the -hat certain schoolboy treasures of almost inestimable value--among them -a lump of chalk, an India-rubber ball, three fishhooks, and one of that -kind of marbles known as a "sure 'nough crystal." Then he tiptoed his -way cautiously among the trees till he felt that he was out of hearing, -and straightway broke into a keen run in the direction of the sandbar. - - - -CHAPTER XV - -A FEW minutes later Tom was in the shoal water of the bar, wading -toward the Illinois shore. Before the depth reached his middle he was -half-way over; the current would permit no more wading, now, so he -struck out confidently to swim the remaining hundred yards. He swam -quartering upstream, but still was swept downward rather faster than he -had expected. However, he reached the shore finally, and drifted along -till he found a low place and drew himself out. He put his hand on his -jacket pocket, found his piece of bark safe, and then struck through -the woods, following the shore, with streaming garments. Shortly before -ten o'clock he came out into an open place opposite the village, and -saw the ferryboat lying in the shadow of the trees and the high bank. -Everything was quiet under the blinking stars. He crept down the bank, -watching with all his eyes, slipped into the water, swam three or four -strokes and climbed into the skiff that did "yawl" duty at the boat's -stern. He laid himself down under the thwarts and waited, panting. - -Presently the cracked bell tapped and a voice gave the order to "cast -off." A minute or two later the skiff's head was standing high up, -against the boat's swell, and the voyage was begun. Tom felt happy in -his success, for he knew it was the boat's last trip for the night. At -the end of a long twelve or fifteen minutes the wheels stopped, and Tom -slipped overboard and swam ashore in the dusk, landing fifty yards -downstream, out of danger of possible stragglers. - -He flew along unfrequented alleys, and shortly found himself at his -aunt's back fence. He climbed over, approached the "ell," and looked in -at the sitting-room window, for a light was burning there. There sat -Aunt Polly, Sid, Mary, and Joe Harper's mother, grouped together, -talking. They were by the bed, and the bed was between them and the -door. Tom went to the door and began to softly lift the latch; then he -pressed gently and the door yielded a crack; he continued pushing -cautiously, and quaking every time it creaked, till he judged he might -squeeze through on his knees; so he put his head through and began, -warily. - -"What makes the candle blow so?" said Aunt Polly. Tom hurried up. -"Why, that door's open, I believe. Why, of course it is. No end of -strange things now. Go 'long and shut it, Sid." - -Tom disappeared under the bed just in time. He lay and "breathed" -himself for a time, and then crept to where he could almost touch his -aunt's foot. - -"But as I was saying," said Aunt Polly, "he warn't BAD, so to say ---only mischEEvous. Only just giddy, and harum-scarum, you know. He -warn't any more responsible than a colt. HE never meant any harm, and -he was the best-hearted boy that ever was"--and she began to cry. - -"It was just so with my Joe--always full of his devilment, and up to -every kind of mischief, but he was just as unselfish and kind as he -could be--and laws bless me, to think I went and whipped him for taking -that cream, never once recollecting that I throwed it out myself -because it was sour, and I never to see him again in this world, never, -never, never, poor abused boy!" And Mrs. Harper sobbed as if her heart -would break. - -"I hope Tom's better off where he is," said Sid, "but if he'd been -better in some ways--" - -"SID!" Tom felt the glare of the old lady's eye, though he could not -see it. "Not a word against my Tom, now that he's gone! God'll take -care of HIM--never you trouble YOURself, sir! Oh, Mrs. Harper, I don't -know how to give him up! I don't know how to give him up! He was such a -comfort to me, although he tormented my old heart out of me, 'most." - -"The Lord giveth and the Lord hath taken away--Blessed be the name of -the Lord! But it's so hard--Oh, it's so hard! Only last Saturday my -Joe busted a firecracker right under my nose and I knocked him -sprawling. Little did I know then, how soon--Oh, if it was to do over -again I'd hug him and bless him for it." - -"Yes, yes, yes, I know just how you feel, Mrs. Harper, I know just -exactly how you feel. No longer ago than yesterday noon, my Tom took -and filled the cat full of Pain-killer, and I did think the cretur -would tear the house down. And God forgive me, I cracked Tom's head -with my thimble, poor boy, poor dead boy. But he's out of all his -troubles now. And the last words I ever heard him say was to reproach--" - -But this memory was too much for the old lady, and she broke entirely -down. Tom was snuffling, now, himself--and more in pity of himself than -anybody else. He could hear Mary crying, and putting in a kindly word -for him from time to time. He began to have a nobler opinion of himself -than ever before. Still, he was sufficiently touched by his aunt's -grief to long to rush out from under the bed and overwhelm her with -joy--and the theatrical gorgeousness of the thing appealed strongly to -his nature, too, but he resisted and lay still. - -He went on listening, and gathered by odds and ends that it was -conjectured at first that the boys had got drowned while taking a swim; -then the small raft had been missed; next, certain boys said the -missing lads had promised that the village should "hear something" -soon; the wise-heads had "put this and that together" and decided that -the lads had gone off on that raft and would turn up at the next town -below, presently; but toward noon the raft had been found, lodged -against the Missouri shore some five or six miles below the village ---and then hope perished; they must be drowned, else hunger would have -driven them home by nightfall if not sooner. It was believed that the -search for the bodies had been a fruitless effort merely because the -drowning must have occurred in mid-channel, since the boys, being good -swimmers, would otherwise have escaped to shore. This was Wednesday -night. If the bodies continued missing until Sunday, all hope would be -given over, and the funerals would be preached on that morning. Tom -shuddered. - -Mrs. Harper gave a sobbing good-night and turned to go. Then with a -mutual impulse the two bereaved women flung themselves into each -other's arms and had a good, consoling cry, and then parted. Aunt Polly -was tender far beyond her wont, in her good-night to Sid and Mary. Sid -snuffled a bit and Mary went off crying with all her heart. - -Aunt Polly knelt down and prayed for Tom so touchingly, so -appealingly, and with such measureless love in her words and her old -trembling voice, that he was weltering in tears again, long before she -was through. - -He had to keep still long after she went to bed, for she kept making -broken-hearted ejaculations from time to time, tossing unrestfully, and -turning over. But at last she was still, only moaning a little in her -sleep. Now the boy stole out, rose gradually by the bedside, shaded the -candle-light with his hand, and stood regarding her. His heart was full -of pity for her. He took out his sycamore scroll and placed it by the -candle. But something occurred to him, and he lingered considering. His -face lighted with a happy solution of his thought; he put the bark -hastily in his pocket. Then he bent over and kissed the faded lips, and -straightway made his stealthy exit, latching the door behind him. - -He threaded his way back to the ferry landing, found nobody at large -there, and walked boldly on board the boat, for he knew she was -tenantless except that there was a watchman, who always turned in and -slept like a graven image. He untied the skiff at the stern, slipped -into it, and was soon rowing cautiously upstream. When he had pulled a -mile above the village, he started quartering across and bent himself -stoutly to his work. He hit the landing on the other side neatly, for -this was a familiar bit of work to him. He was moved to capture the -skiff, arguing that it might be considered a ship and therefore -legitimate prey for a pirate, but he knew a thorough search would be -made for it and that might end in revelations. So he stepped ashore and -entered the woods. - -He sat down and took a long rest, torturing himself meanwhile to keep -awake, and then started warily down the home-stretch. The night was far -spent. It was broad daylight before he found himself fairly abreast the -island bar. He rested again until the sun was well up and gilding the -great river with its splendor, and then he plunged into the stream. A -little later he paused, dripping, upon the threshold of the camp, and -heard Joe say: - -"No, Tom's true-blue, Huck, and he'll come back. He won't desert. He -knows that would be a disgrace to a pirate, and Tom's too proud for -that sort of thing. He's up to something or other. Now I wonder what?" - -"Well, the things is ours, anyway, ain't they?" - -"Pretty near, but not yet, Huck. The writing says they are if he ain't -back here to breakfast." - -"Which he is!" exclaimed Tom, with fine dramatic effect, stepping -grandly into camp. - -A sumptuous breakfast of bacon and fish was shortly provided, and as -the boys set to work upon it, Tom recounted (and adorned) his -adventures. They were a vain and boastful company of heroes when the -tale was done. Then Tom hid himself away in a shady nook to sleep till -noon, and the other pirates got ready to fish and explore. - - - -CHAPTER XVI - -AFTER dinner all the gang turned out to hunt for turtle eggs on the -bar. They went about poking sticks into the sand, and when they found a -soft place they went down on their knees and dug with their hands. -Sometimes they would take fifty or sixty eggs out of one hole. They -were perfectly round white things a trifle smaller than an English -walnut. They had a famous fried-egg feast that night, and another on -Friday morning. - -After breakfast they went whooping and prancing out on the bar, and -chased each other round and round, shedding clothes as they went, until -they were naked, and then continued the frolic far away up the shoal -water of the bar, against the stiff current, which latter tripped their -legs from under them from time to time and greatly increased the fun. -And now and then they stooped in a group and splashed water in each -other's faces with their palms, gradually approaching each other, with -averted faces to avoid the strangling sprays, and finally gripping and -struggling till the best man ducked his neighbor, and then they all -went under in a tangle of white legs and arms and came up blowing, -sputtering, laughing, and gasping for breath at one and the same time. - -When they were well exhausted, they would run out and sprawl on the -dry, hot sand, and lie there and cover themselves up with it, and by -and by break for the water again and go through the original -performance once more. Finally it occurred to them that their naked -skin represented flesh-colored "tights" very fairly; so they drew a -ring in the sand and had a circus--with three clowns in it, for none -would yield this proudest post to his neighbor. - -Next they got their marbles and played "knucks" and "ring-taw" and -"keeps" till that amusement grew stale. Then Joe and Huck had another -swim, but Tom would not venture, because he found that in kicking off -his trousers he had kicked his string of rattlesnake rattles off his -ankle, and he wondered how he had escaped cramp so long without the -protection of this mysterious charm. He did not venture again until he -had found it, and by that time the other boys were tired and ready to -rest. They gradually wandered apart, dropped into the "dumps," and fell -to gazing longingly across the wide river to where the village lay -drowsing in the sun. Tom found himself writing "BECKY" in the sand with -his big toe; he scratched it out, and was angry with himself for his -weakness. But he wrote it again, nevertheless; he could not help it. He -erased it once more and then took himself out of temptation by driving -the other boys together and joining them. - -But Joe's spirits had gone down almost beyond resurrection. He was so -homesick that he could hardly endure the misery of it. The tears lay -very near the surface. Huck was melancholy, too. Tom was downhearted, -but tried hard not to show it. He had a secret which he was not ready -to tell, yet, but if this mutinous depression was not broken up soon, -he would have to bring it out. He said, with a great show of -cheerfulness: - -"I bet there's been pirates on this island before, boys. We'll explore -it again. They've hid treasures here somewhere. How'd you feel to light -on a rotten chest full of gold and silver--hey?" - -But it roused only faint enthusiasm, which faded out, with no reply. -Tom tried one or two other seductions; but they failed, too. It was -discouraging work. Joe sat poking up the sand with a stick and looking -very gloomy. Finally he said: - -"Oh, boys, let's give it up. I want to go home. It's so lonesome." - -"Oh no, Joe, you'll feel better by and by," said Tom. "Just think of -the fishing that's here." - -"I don't care for fishing. I want to go home." - -"But, Joe, there ain't such another swimming-place anywhere." - -"Swimming's no good. I don't seem to care for it, somehow, when there -ain't anybody to say I sha'n't go in. I mean to go home." - -"Oh, shucks! Baby! You want to see your mother, I reckon." - -"Yes, I DO want to see my mother--and you would, too, if you had one. -I ain't any more baby than you are." And Joe snuffled a little. - -"Well, we'll let the cry-baby go home to his mother, won't we, Huck? -Poor thing--does it want to see its mother? And so it shall. You like -it here, don't you, Huck? We'll stay, won't we?" - -Huck said, "Y-e-s"--without any heart in it. - -"I'll never speak to you again as long as I live," said Joe, rising. -"There now!" And he moved moodily away and began to dress himself. - -"Who cares!" said Tom. "Nobody wants you to. Go 'long home and get -laughed at. Oh, you're a nice pirate. Huck and me ain't cry-babies. -We'll stay, won't we, Huck? Let him go if he wants to. I reckon we can -get along without him, per'aps." - -But Tom was uneasy, nevertheless, and was alarmed to see Joe go -sullenly on with his dressing. And then it was discomforting to see -Huck eying Joe's preparations so wistfully, and keeping up such an -ominous silence. Presently, without a parting word, Joe began to wade -off toward the Illinois shore. Tom's heart began to sink. He glanced at -Huck. Huck could not bear the look, and dropped his eyes. Then he said: - -"I want to go, too, Tom. It was getting so lonesome anyway, and now -it'll be worse. Let's us go, too, Tom." - -"I won't! You can all go, if you want to. I mean to stay." - -"Tom, I better go." - -"Well, go 'long--who's hendering you." - -Huck began to pick up his scattered clothes. He said: - -"Tom, I wisht you'd come, too. Now you think it over. We'll wait for -you when we get to shore." - -"Well, you'll wait a blame long time, that's all." - -Huck started sorrowfully away, and Tom stood looking after him, with a -strong desire tugging at his heart to yield his pride and go along too. -He hoped the boys would stop, but they still waded slowly on. It -suddenly dawned on Tom that it was become very lonely and still. He -made one final struggle with his pride, and then darted after his -comrades, yelling: - -"Wait! Wait! I want to tell you something!" - -They presently stopped and turned around. When he got to where they -were, he began unfolding his secret, and they listened moodily till at -last they saw the "point" he was driving at, and then they set up a -war-whoop of applause and said it was "splendid!" and said if he had -told them at first, they wouldn't have started away. He made a plausible -excuse; but his real reason had been the fear that not even the secret -would keep them with him any very great length of time, and so he had -meant to hold it in reserve as a last seduction. - -The lads came gayly back and went at their sports again with a will, -chattering all the time about Tom's stupendous plan and admiring the -genius of it. After a dainty egg and fish dinner, Tom said he wanted to -learn to smoke, now. Joe caught at the idea and said he would like to -try, too. So Huck made pipes and filled them. These novices had never -smoked anything before but cigars made of grape-vine, and they "bit" -the tongue, and were not considered manly anyway. - -Now they stretched themselves out on their elbows and began to puff, -charily, and with slender confidence. The smoke had an unpleasant -taste, and they gagged a little, but Tom said: - -"Why, it's just as easy! If I'd a knowed this was all, I'd a learnt -long ago." - -"So would I," said Joe. "It's just nothing." - -"Why, many a time I've looked at people smoking, and thought well I -wish I could do that; but I never thought I could," said Tom. - -"That's just the way with me, hain't it, Huck? You've heard me talk -just that way--haven't you, Huck? I'll leave it to Huck if I haven't." - -"Yes--heaps of times," said Huck. - -"Well, I have too," said Tom; "oh, hundreds of times. Once down by the -slaughter-house. Don't you remember, Huck? Bob Tanner was there, and -Johnny Miller, and Jeff Thatcher, when I said it. Don't you remember, -Huck, 'bout me saying that?" - -"Yes, that's so," said Huck. "That was the day after I lost a white -alley. No, 'twas the day before." - -"There--I told you so," said Tom. "Huck recollects it." - -"I bleeve I could smoke this pipe all day," said Joe. "I don't feel -sick." - -"Neither do I," said Tom. "I could smoke it all day. But I bet you -Jeff Thatcher couldn't." - -"Jeff Thatcher! Why, he'd keel over just with two draws. Just let him -try it once. HE'D see!" - -"I bet he would. And Johnny Miller--I wish could see Johnny Miller -tackle it once." - -"Oh, don't I!" said Joe. "Why, I bet you Johnny Miller couldn't any -more do this than nothing. Just one little snifter would fetch HIM." - -"'Deed it would, Joe. Say--I wish the boys could see us now." - -"So do I." - -"Say--boys, don't say anything about it, and some time when they're -around, I'll come up to you and say, 'Joe, got a pipe? I want a smoke.' -And you'll say, kind of careless like, as if it warn't anything, you'll -say, 'Yes, I got my OLD pipe, and another one, but my tobacker ain't -very good.' And I'll say, 'Oh, that's all right, if it's STRONG -enough.' And then you'll out with the pipes, and we'll light up just as -ca'm, and then just see 'em look!" - -"By jings, that'll be gay, Tom! I wish it was NOW!" - -"So do I! And when we tell 'em we learned when we was off pirating, -won't they wish they'd been along?" - -"Oh, I reckon not! I'll just BET they will!" - -So the talk ran on. But presently it began to flag a trifle, and grow -disjointed. The silences widened; the expectoration marvellously -increased. Every pore inside the boys' cheeks became a spouting -fountain; they could scarcely bail out the cellars under their tongues -fast enough to prevent an inundation; little overflowings down their -throats occurred in spite of all they could do, and sudden retchings -followed every time. Both boys were looking very pale and miserable, -now. Joe's pipe dropped from his nerveless fingers. Tom's followed. -Both fountains were going furiously and both pumps bailing with might -and main. Joe said feebly: - -"I've lost my knife. I reckon I better go and find it." - -Tom said, with quivering lips and halting utterance: - -"I'll help you. You go over that way and I'll hunt around by the -spring. No, you needn't come, Huck--we can find it." - -So Huck sat down again, and waited an hour. Then he found it lonesome, -and went to find his comrades. They were wide apart in the woods, both -very pale, both fast asleep. But something informed him that if they -had had any trouble they had got rid of it. - -They were not talkative at supper that night. They had a humble look, -and when Huck prepared his pipe after the meal and was going to prepare -theirs, they said no, they were not feeling very well--something they -ate at dinner had disagreed with them. - -About midnight Joe awoke, and called the boys. There was a brooding -oppressiveness in the air that seemed to bode something. The boys -huddled themselves together and sought the friendly companionship of -the fire, though the dull dead heat of the breathless atmosphere was -stifling. They sat still, intent and waiting. The solemn hush -continued. Beyond the light of the fire everything was swallowed up in -the blackness of darkness. Presently there came a quivering glow that -vaguely revealed the foliage for a moment and then vanished. By and by -another came, a little stronger. Then another. Then a faint moan came -sighing through the branches of the forest and the boys felt a fleeting -breath upon their cheeks, and shuddered with the fancy that the Spirit -of the Night had gone by. There was a pause. Now a weird flash turned -night into day and showed every little grass-blade, separate and -distinct, that grew about their feet. And it showed three white, -startled faces, too. A deep peal of thunder went rolling and tumbling -down the heavens and lost itself in sullen rumblings in the distance. A -sweep of chilly air passed by, rustling all the leaves and snowing the -flaky ashes broadcast about the fire. Another fierce glare lit up the -forest and an instant crash followed that seemed to rend the tree-tops -right over the boys' heads. They clung together in terror, in the thick -gloom that followed. A few big rain-drops fell pattering upon the -leaves. - -"Quick! boys, go for the tent!" exclaimed Tom. - -They sprang away, stumbling over roots and among vines in the dark, no -two plunging in the same direction. A furious blast roared through the -trees, making everything sing as it went. One blinding flash after -another came, and peal on peal of deafening thunder. And now a -drenching rain poured down and the rising hurricane drove it in sheets -along the ground. The boys cried out to each other, but the roaring -wind and the booming thunder-blasts drowned their voices utterly. -However, one by one they straggled in at last and took shelter under -the tent, cold, scared, and streaming with water; but to have company -in misery seemed something to be grateful for. They could not talk, the -old sail flapped so furiously, even if the other noises would have -allowed them. The tempest rose higher and higher, and presently the -sail tore loose from its fastenings and went winging away on the blast. -The boys seized each others' hands and fled, with many tumblings and -bruises, to the shelter of a great oak that stood upon the river-bank. -Now the battle was at its highest. Under the ceaseless conflagration of -lightning that flamed in the skies, everything below stood out in -clean-cut and shadowless distinctness: the bending trees, the billowy -river, white with foam, the driving spray of spume-flakes, the dim -outlines of the high bluffs on the other side, glimpsed through the -drifting cloud-rack and the slanting veil of rain. Every little while -some giant tree yielded the fight and fell crashing through the younger -growth; and the unflagging thunder-peals came now in ear-splitting -explosive bursts, keen and sharp, and unspeakably appalling. The storm -culminated in one matchless effort that seemed likely to tear the island -to pieces, burn it up, drown it to the tree-tops, blow it away, and -deafen every creature in it, all at one and the same moment. It was a -wild night for homeless young heads to be out in. - -But at last the battle was done, and the forces retired with weaker -and weaker threatenings and grumblings, and peace resumed her sway. The -boys went back to camp, a good deal awed; but they found there was -still something to be thankful for, because the great sycamore, the -shelter of their beds, was a ruin, now, blasted by the lightnings, and -they were not under it when the catastrophe happened. - -Everything in camp was drenched, the camp-fire as well; for they were -but heedless lads, like their generation, and had made no provision -against rain. Here was matter for dismay, for they were soaked through -and chilled. They were eloquent in their distress; but they presently -discovered that the fire had eaten so far up under the great log it had -been built against (where it curved upward and separated itself from -the ground), that a handbreadth or so of it had escaped wetting; so -they patiently wrought until, with shreds and bark gathered from the -under sides of sheltered logs, they coaxed the fire to burn again. Then -they piled on great dead boughs till they had a roaring furnace, and -were glad-hearted once more. They dried their boiled ham and had a -feast, and after that they sat by the fire and expanded and glorified -their midnight adventure until morning, for there was not a dry spot to -sleep on, anywhere around. - -As the sun began to steal in upon the boys, drowsiness came over them, -and they went out on the sandbar and lay down to sleep. They got -scorched out by and by, and drearily set about getting breakfast. After -the meal they felt rusty, and stiff-jointed, and a little homesick once -more. Tom saw the signs, and fell to cheering up the pirates as well as -he could. But they cared nothing for marbles, or circus, or swimming, -or anything. He reminded them of the imposing secret, and raised a ray -of cheer. While it lasted, he got them interested in a new device. This -was to knock off being pirates, for a while, and be Indians for a -change. They were attracted by this idea; so it was not long before -they were stripped, and striped from head to heel with black mud, like -so many zebras--all of them chiefs, of course--and then they went -tearing through the woods to attack an English settlement. - -By and by they separated into three hostile tribes, and darted upon -each other from ambush with dreadful war-whoops, and killed and scalped -each other by thousands. It was a gory day. Consequently it was an -extremely satisfactory one. - -They assembled in camp toward supper-time, hungry and happy; but now a -difficulty arose--hostile Indians could not break the bread of -hospitality together without first making peace, and this was a simple -impossibility without smoking a pipe of peace. There was no other -process that ever they had heard of. Two of the savages almost wished -they had remained pirates. However, there was no other way; so with -such show of cheerfulness as they could muster they called for the pipe -and took their whiff as it passed, in due form. - -And behold, they were glad they had gone into savagery, for they had -gained something; they found that they could now smoke a little without -having to go and hunt for a lost knife; they did not get sick enough to -be seriously uncomfortable. They were not likely to fool away this high -promise for lack of effort. No, they practised cautiously, after -supper, with right fair success, and so they spent a jubilant evening. -They were prouder and happier in their new acquirement than they would -have been in the scalping and skinning of the Six Nations. We will -leave them to smoke and chatter and brag, since we have no further use -for them at present. - - - -CHAPTER XVII - -BUT there was no hilarity in the little town that same tranquil -Saturday afternoon. The Harpers, and Aunt Polly's family, were being -put into mourning, with great grief and many tears. An unusual quiet -possessed the village, although it was ordinarily quiet enough, in all -conscience. The villagers conducted their concerns with an absent air, -and talked little; but they sighed often. The Saturday holiday seemed a -burden to the children. They had no heart in their sports, and -gradually gave them up. - -In the afternoon Becky Thatcher found herself moping about the -deserted schoolhouse yard, and feeling very melancholy. But she found -nothing there to comfort her. She soliloquized: - -"Oh, if I only had a brass andiron-knob again! But I haven't got -anything now to remember him by." And she choked back a little sob. - -Presently she stopped, and said to herself: - -"It was right here. Oh, if it was to do over again, I wouldn't say -that--I wouldn't say it for the whole world. But he's gone now; I'll -never, never, never see him any more." - -This thought broke her down, and she wandered away, with tears rolling -down her cheeks. Then quite a group of boys and girls--playmates of -Tom's and Joe's--came by, and stood looking over the paling fence and -talking in reverent tones of how Tom did so-and-so the last time they -saw him, and how Joe said this and that small trifle (pregnant with -awful prophecy, as they could easily see now!)--and each speaker -pointed out the exact spot where the lost lads stood at the time, and -then added something like "and I was a-standing just so--just as I am -now, and as if you was him--I was as close as that--and he smiled, just -this way--and then something seemed to go all over me, like--awful, you -know--and I never thought what it meant, of course, but I can see now!" - -Then there was a dispute about who saw the dead boys last in life, and -many claimed that dismal distinction, and offered evidences, more or -less tampered with by the witness; and when it was ultimately decided -who DID see the departed last, and exchanged the last words with them, -the lucky parties took upon themselves a sort of sacred importance, and -were gaped at and envied by all the rest. One poor chap, who had no -other grandeur to offer, said with tolerably manifest pride in the -remembrance: - -"Well, Tom Sawyer he licked me once." - -But that bid for glory was a failure. Most of the boys could say that, -and so that cheapened the distinction too much. The group loitered -away, still recalling memories of the lost heroes, in awed voices. - -When the Sunday-school hour was finished, the next morning, the bell -began to toll, instead of ringing in the usual way. It was a very still -Sabbath, and the mournful sound seemed in keeping with the musing hush -that lay upon nature. The villagers began to gather, loitering a moment -in the vestibule to converse in whispers about the sad event. But there -was no whispering in the house; only the funereal rustling of dresses -as the women gathered to their seats disturbed the silence there. None -could remember when the little church had been so full before. There -was finally a waiting pause, an expectant dumbness, and then Aunt Polly -entered, followed by Sid and Mary, and they by the Harper family, all -in deep black, and the whole congregation, the old minister as well, -rose reverently and stood until the mourners were seated in the front -pew. There was another communing silence, broken at intervals by -muffled sobs, and then the minister spread his hands abroad and prayed. -A moving hymn was sung, and the text followed: "I am the Resurrection -and the Life." - -As the service proceeded, the clergyman drew such pictures of the -graces, the winning ways, and the rare promise of the lost lads that -every soul there, thinking he recognized these pictures, felt a pang in -remembering that he had persistently blinded himself to them always -before, and had as persistently seen only faults and flaws in the poor -boys. The minister related many a touching incident in the lives of the -departed, too, which illustrated their sweet, generous natures, and the -people could easily see, now, how noble and beautiful those episodes -were, and remembered with grief that at the time they occurred they had -seemed rank rascalities, well deserving of the cowhide. The -congregation became more and more moved, as the pathetic tale went on, -till at last the whole company broke down and joined the weeping -mourners in a chorus of anguished sobs, the preacher himself giving way -to his feelings, and crying in the pulpit. - -There was a rustle in the gallery, which nobody noticed; a moment -later the church door creaked; the minister raised his streaming eyes -above his handkerchief, and stood transfixed! First one and then -another pair of eyes followed the minister's, and then almost with one -impulse the congregation rose and stared while the three dead boys came -marching up the aisle, Tom in the lead, Joe next, and Huck, a ruin of -drooping rags, sneaking sheepishly in the rear! They had been hid in -the unused gallery listening to their own funeral sermon! - -Aunt Polly, Mary, and the Harpers threw themselves upon their restored -ones, smothered them with kisses and poured out thanksgivings, while -poor Huck stood abashed and uncomfortable, not knowing exactly what to -do or where to hide from so many unwelcoming eyes. He wavered, and -started to slink away, but Tom seized him and said: - -"Aunt Polly, it ain't fair. Somebody's got to be glad to see Huck." - -"And so they shall. I'm glad to see him, poor motherless thing!" And -the loving attentions Aunt Polly lavished upon him were the one thing -capable of making him more uncomfortable than he was before. - -Suddenly the minister shouted at the top of his voice: "Praise God -from whom all blessings flow--SING!--and put your hearts in it!" - -And they did. Old Hundred swelled up with a triumphant burst, and -while it shook the rafters Tom Sawyer the Pirate looked around upon the -envying juveniles about him and confessed in his heart that this was -the proudest moment of his life. - -As the "sold" congregation trooped out they said they would almost be -willing to be made ridiculous again to hear Old Hundred sung like that -once more. - -Tom got more cuffs and kisses that day--according to Aunt Polly's -varying moods--than he had earned before in a year; and he hardly knew -which expressed the most gratefulness to God and affection for himself. - - - -CHAPTER XVIII - -THAT was Tom's great secret--the scheme to return home with his -brother pirates and attend their own funerals. They had paddled over to -the Missouri shore on a log, at dusk on Saturday, landing five or six -miles below the village; they had slept in the woods at the edge of the -town till nearly daylight, and had then crept through back lanes and -alleys and finished their sleep in the gallery of the church among a -chaos of invalided benches. - -At breakfast, Monday morning, Aunt Polly and Mary were very loving to -Tom, and very attentive to his wants. There was an unusual amount of -talk. In the course of it Aunt Polly said: - -"Well, I don't say it wasn't a fine joke, Tom, to keep everybody -suffering 'most a week so you boys had a good time, but it is a pity -you could be so hard-hearted as to let me suffer so. If you could come -over on a log to go to your funeral, you could have come over and give -me a hint some way that you warn't dead, but only run off." - -"Yes, you could have done that, Tom," said Mary; "and I believe you -would if you had thought of it." - -"Would you, Tom?" said Aunt Polly, her face lighting wistfully. "Say, -now, would you, if you'd thought of it?" - -"I--well, I don't know. 'Twould 'a' spoiled everything." - -"Tom, I hoped you loved me that much," said Aunt Polly, with a grieved -tone that discomforted the boy. "It would have been something if you'd -cared enough to THINK of it, even if you didn't DO it." - -"Now, auntie, that ain't any harm," pleaded Mary; "it's only Tom's -giddy way--he is always in such a rush that he never thinks of -anything." - -"More's the pity. Sid would have thought. And Sid would have come and -DONE it, too. Tom, you'll look back, some day, when it's too late, and -wish you'd cared a little more for me when it would have cost you so -little." - -"Now, auntie, you know I do care for you," said Tom. - -"I'd know it better if you acted more like it." - -"I wish now I'd thought," said Tom, with a repentant tone; "but I -dreamt about you, anyway. That's something, ain't it?" - -"It ain't much--a cat does that much--but it's better than nothing. -What did you dream?" - -"Why, Wednesday night I dreamt that you was sitting over there by the -bed, and Sid was sitting by the woodbox, and Mary next to him." - -"Well, so we did. So we always do. I'm glad your dreams could take -even that much trouble about us." - -"And I dreamt that Joe Harper's mother was here." - -"Why, she was here! Did you dream any more?" - -"Oh, lots. But it's so dim, now." - -"Well, try to recollect--can't you?" - -"Somehow it seems to me that the wind--the wind blowed the--the--" - -"Try harder, Tom! The wind did blow something. Come!" - -Tom pressed his fingers on his forehead an anxious minute, and then -said: - -"I've got it now! I've got it now! It blowed the candle!" - -"Mercy on us! Go on, Tom--go on!" - -"And it seems to me that you said, 'Why, I believe that that door--'" - -"Go ON, Tom!" - -"Just let me study a moment--just a moment. Oh, yes--you said you -believed the door was open." - -"As I'm sitting here, I did! Didn't I, Mary! Go on!" - -"And then--and then--well I won't be certain, but it seems like as if -you made Sid go and--and--" - -"Well? Well? What did I make him do, Tom? What did I make him do?" - -"You made him--you--Oh, you made him shut it." - -"Well, for the land's sake! I never heard the beat of that in all my -days! Don't tell ME there ain't anything in dreams, any more. Sereny -Harper shall know of this before I'm an hour older. I'd like to see her -get around THIS with her rubbage 'bout superstition. Go on, Tom!" - -"Oh, it's all getting just as bright as day, now. Next you said I -warn't BAD, only mischeevous and harum-scarum, and not any more -responsible than--than--I think it was a colt, or something." - -"And so it was! Well, goodness gracious! Go on, Tom!" - -"And then you began to cry." - -"So I did. So I did. Not the first time, neither. And then--" - -"Then Mrs. Harper she began to cry, and said Joe was just the same, -and she wished she hadn't whipped him for taking cream when she'd -throwed it out her own self--" - -"Tom! The sperrit was upon you! You was a prophesying--that's what you -was doing! Land alive, go on, Tom!" - -"Then Sid he said--he said--" - -"I don't think I said anything," said Sid. - -"Yes you did, Sid," said Mary. - -"Shut your heads and let Tom go on! What did he say, Tom?" - -"He said--I THINK he said he hoped I was better off where I was gone -to, but if I'd been better sometimes--" - -"THERE, d'you hear that! It was his very words!" - -"And you shut him up sharp." - -"I lay I did! There must 'a' been an angel there. There WAS an angel -there, somewheres!" - -"And Mrs. Harper told about Joe scaring her with a firecracker, and -you told about Peter and the Painkiller--" - -"Just as true as I live!" - -"And then there was a whole lot of talk 'bout dragging the river for -us, and 'bout having the funeral Sunday, and then you and old Miss -Harper hugged and cried, and she went." - -"It happened just so! It happened just so, as sure as I'm a-sitting in -these very tracks. Tom, you couldn't told it more like if you'd 'a' -seen it! And then what? Go on, Tom!" - -"Then I thought you prayed for me--and I could see you and hear every -word you said. And you went to bed, and I was so sorry that I took and -wrote on a piece of sycamore bark, 'We ain't dead--we are only off -being pirates,' and put it on the table by the candle; and then you -looked so good, laying there asleep, that I thought I went and leaned -over and kissed you on the lips." - -"Did you, Tom, DID you! I just forgive you everything for that!" And -she seized the boy in a crushing embrace that made him feel like the -guiltiest of villains. - -"It was very kind, even though it was only a--dream," Sid soliloquized -just audibly. - -"Shut up, Sid! A body does just the same in a dream as he'd do if he -was awake. Here's a big Milum apple I've been saving for you, Tom, if -you was ever found again--now go 'long to school. I'm thankful to the -good God and Father of us all I've got you back, that's long-suffering -and merciful to them that believe on Him and keep His word, though -goodness knows I'm unworthy of it, but if only the worthy ones got His -blessings and had His hand to help them over the rough places, there's -few enough would smile here or ever enter into His rest when the long -night comes. Go 'long Sid, Mary, Tom--take yourselves off--you've -hendered me long enough." - -The children left for school, and the old lady to call on Mrs. Harper -and vanquish her realism with Tom's marvellous dream. Sid had better -judgment than to utter the thought that was in his mind as he left the -house. It was this: "Pretty thin--as long a dream as that, without any -mistakes in it!" - -What a hero Tom was become, now! He did not go skipping and prancing, -but moved with a dignified swagger as became a pirate who felt that the -public eye was on him. And indeed it was; he tried not to seem to see -the looks or hear the remarks as he passed along, but they were food -and drink to him. Smaller boys than himself flocked at his heels, as -proud to be seen with him, and tolerated by him, as if he had been the -drummer at the head of a procession or the elephant leading a menagerie -into town. Boys of his own size pretended not to know he had been away -at all; but they were consuming with envy, nevertheless. They would -have given anything to have that swarthy suntanned skin of his, and his -glittering notoriety; and Tom would not have parted with either for a -circus. - -At school the children made so much of him and of Joe, and delivered -such eloquent admiration from their eyes, that the two heroes were not -long in becoming insufferably "stuck-up." They began to tell their -adventures to hungry listeners--but they only began; it was not a thing -likely to have an end, with imaginations like theirs to furnish -material. And finally, when they got out their pipes and went serenely -puffing around, the very summit of glory was reached. - -Tom decided that he could be independent of Becky Thatcher now. Glory -was sufficient. He would live for glory. Now that he was distinguished, -maybe she would be wanting to "make up." Well, let her--she should see -that he could be as indifferent as some other people. Presently she -arrived. Tom pretended not to see her. He moved away and joined a group -of boys and girls and began to talk. Soon he observed that she was -tripping gayly back and forth with flushed face and dancing eyes, -pretending to be busy chasing schoolmates, and screaming with laughter -when she made a capture; but he noticed that she always made her -captures in his vicinity, and that she seemed to cast a conscious eye -in his direction at such times, too. It gratified all the vicious -vanity that was in him; and so, instead of winning him, it only "set -him up" the more and made him the more diligent to avoid betraying that -he knew she was about. Presently she gave over skylarking, and moved -irresolutely about, sighing once or twice and glancing furtively and -wistfully toward Tom. Then she observed that now Tom was talking more -particularly to Amy Lawrence than to any one else. She felt a sharp -pang and grew disturbed and uneasy at once. She tried to go away, but -her feet were treacherous, and carried her to the group instead. She -said to a girl almost at Tom's elbow--with sham vivacity: - -"Why, Mary Austin! you bad girl, why didn't you come to Sunday-school?" - -"I did come--didn't you see me?" - -"Why, no! Did you? Where did you sit?" - -"I was in Miss Peters' class, where I always go. I saw YOU." - -"Did you? Why, it's funny I didn't see you. I wanted to tell you about -the picnic." - -"Oh, that's jolly. Who's going to give it?" - -"My ma's going to let me have one." - -"Oh, goody; I hope she'll let ME come." - -"Well, she will. The picnic's for me. She'll let anybody come that I -want, and I want you." - -"That's ever so nice. When is it going to be?" - -"By and by. Maybe about vacation." - -"Oh, won't it be fun! You going to have all the girls and boys?" - -"Yes, every one that's friends to me--or wants to be"; and she glanced -ever so furtively at Tom, but he talked right along to Amy Lawrence -about the terrible storm on the island, and how the lightning tore the -great sycamore tree "all to flinders" while he was "standing within -three feet of it." - -"Oh, may I come?" said Grace Miller. - -"Yes." - -"And me?" said Sally Rogers. - -"Yes." - -"And me, too?" said Susy Harper. "And Joe?" - -"Yes." - -And so on, with clapping of joyful hands till all the group had begged -for invitations but Tom and Amy. Then Tom turned coolly away, still -talking, and took Amy with him. Becky's lips trembled and the tears -came to her eyes; she hid these signs with a forced gayety and went on -chattering, but the life had gone out of the picnic, now, and out of -everything else; she got away as soon as she could and hid herself and -had what her sex call "a good cry." Then she sat moody, with wounded -pride, till the bell rang. She roused up, now, with a vindictive cast -in her eye, and gave her plaited tails a shake and said she knew what -SHE'D do. - -At recess Tom continued his flirtation with Amy with jubilant -self-satisfaction. And he kept drifting about to find Becky and lacerate -her with the performance. At last he spied her, but there was a sudden -falling of his mercury. She was sitting cosily on a little bench behind -the schoolhouse looking at a picture-book with Alfred Temple--and so -absorbed were they, and their heads so close together over the book, -that they did not seem to be conscious of anything in the world besides. -Jealousy ran red-hot through Tom's veins. He began to hate himself for -throwing away the chance Becky had offered for a reconciliation. He -called himself a fool, and all the hard names he could think of. He -wanted to cry with vexation. Amy chatted happily along, as they walked, -for her heart was singing, but Tom's tongue had lost its function. He -did not hear what Amy was saying, and whenever she paused expectantly he -could only stammer an awkward assent, which was as often misplaced as -otherwise. He kept drifting to the rear of the schoolhouse, again and -again, to sear his eyeballs with the hateful spectacle there. He could -not help it. And it maddened him to see, as he thought he saw, that -Becky Thatcher never once suspected that he was even in the land of the -living. But she did see, nevertheless; and she knew she was winning her -fight, too, and was glad to see him suffer as she had suffered. - -Amy's happy prattle became intolerable. Tom hinted at things he had to -attend to; things that must be done; and time was fleeting. But in -vain--the girl chirped on. Tom thought, "Oh, hang her, ain't I ever -going to get rid of her?" At last he must be attending to those -things--and she said artlessly that she would be "around" when school -let out. And he hastened away, hating her for it. - -"Any other boy!" Tom thought, grating his teeth. "Any boy in the whole -town but that Saint Louis smarty that thinks he dresses so fine and is -aristocracy! Oh, all right, I licked you the first day you ever saw -this town, mister, and I'll lick you again! You just wait till I catch -you out! I'll just take and--" - -And he went through the motions of thrashing an imaginary boy ---pummelling the air, and kicking and gouging. "Oh, you do, do you? You -holler 'nough, do you? Now, then, let that learn you!" And so the -imaginary flogging was finished to his satisfaction. - -Tom fled home at noon. His conscience could not endure any more of -Amy's grateful happiness, and his jealousy could bear no more of the -other distress. Becky resumed her picture inspections with Alfred, but -as the minutes dragged along and no Tom came to suffer, her triumph -began to cloud and she lost interest; gravity and absent-mindedness -followed, and then melancholy; two or three times she pricked up her -ear at a footstep, but it was a false hope; no Tom came. At last she -grew entirely miserable and wished she hadn't carried it so far. When -poor Alfred, seeing that he was losing her, he did not know how, kept -exclaiming: "Oh, here's a jolly one! look at this!" she lost patience -at last, and said, "Oh, don't bother me! I don't care for them!" and -burst into tears, and got up and walked away. - -Alfred dropped alongside and was going to try to comfort her, but she -said: - -"Go away and leave me alone, can't you! I hate you!" - -So the boy halted, wondering what he could have done--for she had said -she would look at pictures all through the nooning--and she walked on, -crying. Then Alfred went musing into the deserted schoolhouse. He was -humiliated and angry. He easily guessed his way to the truth--the girl -had simply made a convenience of him to vent her spite upon Tom Sawyer. -He was far from hating Tom the less when this thought occurred to him. -He wished there was some way to get that boy into trouble without much -risk to himself. Tom's spelling-book fell under his eye. Here was his -opportunity. He gratefully opened to the lesson for the afternoon and -poured ink upon the page. - -Becky, glancing in at a window behind him at the moment, saw the act, -and moved on, without discovering herself. She started homeward, now, -intending to find Tom and tell him; Tom would be thankful and their -troubles would be healed. Before she was half way home, however, she -had changed her mind. The thought of Tom's treatment of her when she -was talking about her picnic came scorching back and filled her with -shame. She resolved to let him get whipped on the damaged -spelling-book's account, and to hate him forever, into the bargain. - - - -CHAPTER XIX - -TOM arrived at home in a dreary mood, and the first thing his aunt -said to him showed him that he had brought his sorrows to an -unpromising market: - -"Tom, I've a notion to skin you alive!" - -"Auntie, what have I done?" - -"Well, you've done enough. Here I go over to Sereny Harper, like an -old softy, expecting I'm going to make her believe all that rubbage -about that dream, when lo and behold you she'd found out from Joe that -you was over here and heard all the talk we had that night. Tom, I -don't know what is to become of a boy that will act like that. It makes -me feel so bad to think you could let me go to Sereny Harper and make -such a fool of myself and never say a word." - -This was a new aspect of the thing. His smartness of the morning had -seemed to Tom a good joke before, and very ingenious. It merely looked -mean and shabby now. He hung his head and could not think of anything -to say for a moment. Then he said: - -"Auntie, I wish I hadn't done it--but I didn't think." - -"Oh, child, you never think. You never think of anything but your own -selfishness. You could think to come all the way over here from -Jackson's Island in the night to laugh at our troubles, and you could -think to fool me with a lie about a dream; but you couldn't ever think -to pity us and save us from sorrow." - -"Auntie, I know now it was mean, but I didn't mean to be mean. I -didn't, honest. And besides, I didn't come over here to laugh at you -that night." - -"What did you come for, then?" - -"It was to tell you not to be uneasy about us, because we hadn't got -drownded." - -"Tom, Tom, I would be the thankfullest soul in this world if I could -believe you ever had as good a thought as that, but you know you never -did--and I know it, Tom." - -"Indeed and 'deed I did, auntie--I wish I may never stir if I didn't." - -"Oh, Tom, don't lie--don't do it. It only makes things a hundred times -worse." - -"It ain't a lie, auntie; it's the truth. I wanted to keep you from -grieving--that was all that made me come." - -"I'd give the whole world to believe that--it would cover up a power -of sins, Tom. I'd 'most be glad you'd run off and acted so bad. But it -ain't reasonable; because, why didn't you tell me, child?" - -"Why, you see, when you got to talking about the funeral, I just got -all full of the idea of our coming and hiding in the church, and I -couldn't somehow bear to spoil it. So I just put the bark back in my -pocket and kept mum." - -"What bark?" - -"The bark I had wrote on to tell you we'd gone pirating. I wish, now, -you'd waked up when I kissed you--I do, honest." - -The hard lines in his aunt's face relaxed and a sudden tenderness -dawned in her eyes. - -"DID you kiss me, Tom?" - -"Why, yes, I did." - -"Are you sure you did, Tom?" - -"Why, yes, I did, auntie--certain sure." - -"What did you kiss me for, Tom?" - -"Because I loved you so, and you laid there moaning and I was so sorry." - -The words sounded like truth. The old lady could not hide a tremor in -her voice when she said: - -"Kiss me again, Tom!--and be off with you to school, now, and don't -bother me any more." - -The moment he was gone, she ran to a closet and got out the ruin of a -jacket which Tom had gone pirating in. Then she stopped, with it in her -hand, and said to herself: - -"No, I don't dare. Poor boy, I reckon he's lied about it--but it's a -blessed, blessed lie, there's such a comfort come from it. I hope the -Lord--I KNOW the Lord will forgive him, because it was such -goodheartedness in him to tell it. But I don't want to find out it's a -lie. I won't look." - -She put the jacket away, and stood by musing a minute. Twice she put -out her hand to take the garment again, and twice she refrained. Once -more she ventured, and this time she fortified herself with the -thought: "It's a good lie--it's a good lie--I won't let it grieve me." -So she sought the jacket pocket. A moment later she was reading Tom's -piece of bark through flowing tears and saying: "I could forgive the -boy, now, if he'd committed a million sins!" - - - -CHAPTER XX - -THERE was something about Aunt Polly's manner, when she kissed Tom, -that swept away his low spirits and made him lighthearted and happy -again. He started to school and had the luck of coming upon Becky -Thatcher at the head of Meadow Lane. His mood always determined his -manner. Without a moment's hesitation he ran to her and said: - -"I acted mighty mean to-day, Becky, and I'm so sorry. I won't ever, -ever do that way again, as long as ever I live--please make up, won't -you?" - -The girl stopped and looked him scornfully in the face: - -"I'll thank you to keep yourself TO yourself, Mr. Thomas Sawyer. I'll -never speak to you again." - -She tossed her head and passed on. Tom was so stunned that he had not -even presence of mind enough to say "Who cares, Miss Smarty?" until the -right time to say it had gone by. So he said nothing. But he was in a -fine rage, nevertheless. He moped into the schoolyard wishing she were -a boy, and imagining how he would trounce her if she were. He presently -encountered her and delivered a stinging remark as he passed. She -hurled one in return, and the angry breach was complete. It seemed to -Becky, in her hot resentment, that she could hardly wait for school to -"take in," she was so impatient to see Tom flogged for the injured -spelling-book. If she had had any lingering notion of exposing Alfred -Temple, Tom's offensive fling had driven it entirely away. - -Poor girl, she did not know how fast she was nearing trouble herself. -The master, Mr. Dobbins, had reached middle age with an unsatisfied -ambition. The darling of his desires was, to be a doctor, but poverty -had decreed that he should be nothing higher than a village -schoolmaster. Every day he took a mysterious book out of his desk and -absorbed himself in it at times when no classes were reciting. He kept -that book under lock and key. There was not an urchin in school but was -perishing to have a glimpse of it, but the chance never came. Every boy -and girl had a theory about the nature of that book; but no two -theories were alike, and there was no way of getting at the facts in -the case. Now, as Becky was passing by the desk, which stood near the -door, she noticed that the key was in the lock! It was a precious -moment. She glanced around; found herself alone, and the next instant -she had the book in her hands. The title-page--Professor Somebody's -ANATOMY--carried no information to her mind; so she began to turn the -leaves. She came at once upon a handsomely engraved and colored -frontispiece--a human figure, stark naked. At that moment a shadow fell -on the page and Tom Sawyer stepped in at the door and caught a glimpse -of the picture. Becky snatched at the book to close it, and had the -hard luck to tear the pictured page half down the middle. She thrust -the volume into the desk, turned the key, and burst out crying with -shame and vexation. - -"Tom Sawyer, you are just as mean as you can be, to sneak up on a -person and look at what they're looking at." - -"How could I know you was looking at anything?" - -"You ought to be ashamed of yourself, Tom Sawyer; you know you're -going to tell on me, and oh, what shall I do, what shall I do! I'll be -whipped, and I never was whipped in school." - -Then she stamped her little foot and said: - -"BE so mean if you want to! I know something that's going to happen. -You just wait and you'll see! Hateful, hateful, hateful!"--and she -flung out of the house with a new explosion of crying. - -Tom stood still, rather flustered by this onslaught. Presently he said -to himself: - -"What a curious kind of a fool a girl is! Never been licked in school! -Shucks! What's a licking! That's just like a girl--they're so -thin-skinned and chicken-hearted. Well, of course I ain't going to tell -old Dobbins on this little fool, because there's other ways of getting -even on her, that ain't so mean; but what of it? Old Dobbins will ask -who it was tore his book. Nobody'll answer. Then he'll do just the way -he always does--ask first one and then t'other, and when he comes to the -right girl he'll know it, without any telling. Girls' faces always tell -on them. They ain't got any backbone. She'll get licked. Well, it's a -kind of a tight place for Becky Thatcher, because there ain't any way -out of it." Tom conned the thing a moment longer, and then added: "All -right, though; she'd like to see me in just such a fix--let her sweat it -out!" - -Tom joined the mob of skylarking scholars outside. In a few moments -the master arrived and school "took in." Tom did not feel a strong -interest in his studies. Every time he stole a glance at the girls' -side of the room Becky's face troubled him. Considering all things, he -did not want to pity her, and yet it was all he could do to help it. He -could get up no exultation that was really worthy the name. Presently -the spelling-book discovery was made, and Tom's mind was entirely full -of his own matters for a while after that. Becky roused up from her -lethargy of distress and showed good interest in the proceedings. She -did not expect that Tom could get out of his trouble by denying that he -spilt the ink on the book himself; and she was right. The denial only -seemed to make the thing worse for Tom. Becky supposed she would be -glad of that, and she tried to believe she was glad of it, but she -found she was not certain. When the worst came to the worst, she had an -impulse to get up and tell on Alfred Temple, but she made an effort and -forced herself to keep still--because, said she to herself, "he'll tell -about me tearing the picture sure. I wouldn't say a word, not to save -his life!" - -Tom took his whipping and went back to his seat not at all -broken-hearted, for he thought it was possible that he had unknowingly -upset the ink on the spelling-book himself, in some skylarking bout--he -had denied it for form's sake and because it was custom, and had stuck -to the denial from principle. - -A whole hour drifted by, the master sat nodding in his throne, the air -was drowsy with the hum of study. By and by, Mr. Dobbins straightened -himself up, yawned, then unlocked his desk, and reached for his book, -but seemed undecided whether to take it out or leave it. Most of the -pupils glanced up languidly, but there were two among them that watched -his movements with intent eyes. Mr. Dobbins fingered his book absently -for a while, then took it out and settled himself in his chair to read! -Tom shot a glance at Becky. He had seen a hunted and helpless rabbit -look as she did, with a gun levelled at its head. Instantly he forgot -his quarrel with her. Quick--something must be done! done in a flash, -too! But the very imminence of the emergency paralyzed his invention. -Good!--he had an inspiration! He would run and snatch the book, spring -through the door and fly. But his resolution shook for one little -instant, and the chance was lost--the master opened the volume. If Tom -only had the wasted opportunity back again! Too late. There was no help -for Becky now, he said. The next moment the master faced the school. -Every eye sank under his gaze. There was that in it which smote even -the innocent with fear. There was silence while one might count ten ---the master was gathering his wrath. Then he spoke: "Who tore this book?" - -There was not a sound. One could have heard a pin drop. The stillness -continued; the master searched face after face for signs of guilt. - -"Benjamin Rogers, did you tear this book?" - -A denial. Another pause. - -"Joseph Harper, did you?" - -Another denial. Tom's uneasiness grew more and more intense under the -slow torture of these proceedings. The master scanned the ranks of -boys--considered a while, then turned to the girls: - -"Amy Lawrence?" - -A shake of the head. - -"Gracie Miller?" - -The same sign. - -"Susan Harper, did you do this?" - -Another negative. The next girl was Becky Thatcher. Tom was trembling -from head to foot with excitement and a sense of the hopelessness of -the situation. - -"Rebecca Thatcher" [Tom glanced at her face--it was white with terror] ---"did you tear--no, look me in the face" [her hands rose in appeal] ---"did you tear this book?" - -A thought shot like lightning through Tom's brain. He sprang to his -feet and shouted--"I done it!" - -The school stared in perplexity at this incredible folly. Tom stood a -moment, to gather his dismembered faculties; and when he stepped -forward to go to his punishment the surprise, the gratitude, the -adoration that shone upon him out of poor Becky's eyes seemed pay -enough for a hundred floggings. Inspired by the splendor of his own -act, he took without an outcry the most merciless flaying that even Mr. -Dobbins had ever administered; and also received with indifference the -added cruelty of a command to remain two hours after school should be -dismissed--for he knew who would wait for him outside till his -captivity was done, and not count the tedious time as loss, either. - -Tom went to bed that night planning vengeance against Alfred Temple; -for with shame and repentance Becky had told him all, not forgetting -her own treachery; but even the longing for vengeance had to give way, -soon, to pleasanter musings, and he fell asleep at last with Becky's -latest words lingering dreamily in his ear-- - -"Tom, how COULD you be so noble!" - - - -CHAPTER XXI - -VACATION was approaching. The schoolmaster, always severe, grew -severer and more exacting than ever, for he wanted the school to make a -good showing on "Examination" day. His rod and his ferule were seldom -idle now--at least among the smaller pupils. Only the biggest boys, and -young ladies of eighteen and twenty, escaped lashing. Mr. Dobbins' -lashings were very vigorous ones, too; for although he carried, under -his wig, a perfectly bald and shiny head, he had only reached middle -age, and there was no sign of feebleness in his muscle. As the great -day approached, all the tyranny that was in him came to the surface; he -seemed to take a vindictive pleasure in punishing the least -shortcomings. The consequence was, that the smaller boys spent their -days in terror and suffering and their nights in plotting revenge. They -threw away no opportunity to do the master a mischief. But he kept -ahead all the time. The retribution that followed every vengeful -success was so sweeping and majestic that the boys always retired from -the field badly worsted. At last they conspired together and hit upon a -plan that promised a dazzling victory. They swore in the sign-painter's -boy, told him the scheme, and asked his help. He had his own reasons -for being delighted, for the master boarded in his father's family and -had given the boy ample cause to hate him. The master's wife would go -on a visit to the country in a few days, and there would be nothing to -interfere with the plan; the master always prepared himself for great -occasions by getting pretty well fuddled, and the sign-painter's boy -said that when the dominie had reached the proper condition on -Examination Evening he would "manage the thing" while he napped in his -chair; then he would have him awakened at the right time and hurried -away to school. - -In the fulness of time the interesting occasion arrived. At eight in -the evening the schoolhouse was brilliantly lighted, and adorned with -wreaths and festoons of foliage and flowers. The master sat throned in -his great chair upon a raised platform, with his blackboard behind him. -He was looking tolerably mellow. Three rows of benches on each side and -six rows in front of him were occupied by the dignitaries of the town -and by the parents of the pupils. To his left, back of the rows of -citizens, was a spacious temporary platform upon which were seated the -scholars who were to take part in the exercises of the evening; rows of -small boys, washed and dressed to an intolerable state of discomfort; -rows of gawky big boys; snowbanks of girls and young ladies clad in -lawn and muslin and conspicuously conscious of their bare arms, their -grandmothers' ancient trinkets, their bits of pink and blue ribbon and -the flowers in their hair. All the rest of the house was filled with -non-participating scholars. - -The exercises began. A very little boy stood up and sheepishly -recited, "You'd scarce expect one of my age to speak in public on the -stage," etc.--accompanying himself with the painfully exact and -spasmodic gestures which a machine might have used--supposing the -machine to be a trifle out of order. But he got through safely, though -cruelly scared, and got a fine round of applause when he made his -manufactured bow and retired. - -A little shamefaced girl lisped, "Mary had a little lamb," etc., -performed a compassion-inspiring curtsy, got her meed of applause, and -sat down flushed and happy. - -Tom Sawyer stepped forward with conceited confidence and soared into -the unquenchable and indestructible "Give me liberty or give me death" -speech, with fine fury and frantic gesticulation, and broke down in the -middle of it. A ghastly stage-fright seized him, his legs quaked under -him and he was like to choke. True, he had the manifest sympathy of the -house but he had the house's silence, too, which was even worse than -its sympathy. The master frowned, and this completed the disaster. Tom -struggled awhile and then retired, utterly defeated. There was a weak -attempt at applause, but it died early. - -"The Boy Stood on the Burning Deck" followed; also "The Assyrian Came -Down," and other declamatory gems. Then there were reading exercises, -and a spelling fight. The meagre Latin class recited with honor. The -prime feature of the evening was in order, now--original "compositions" -by the young ladies. Each in her turn stepped forward to the edge of -the platform, cleared her throat, held up her manuscript (tied with -dainty ribbon), and proceeded to read, with labored attention to -"expression" and punctuation. The themes were the same that had been -illuminated upon similar occasions by their mothers before them, their -grandmothers, and doubtless all their ancestors in the female line -clear back to the Crusades. "Friendship" was one; "Memories of Other -Days"; "Religion in History"; "Dream Land"; "The Advantages of -Culture"; "Forms of Political Government Compared and Contrasted"; -"Melancholy"; "Filial Love"; "Heart Longings," etc., etc. - -A prevalent feature in these compositions was a nursed and petted -melancholy; another was a wasteful and opulent gush of "fine language"; -another was a tendency to lug in by the ears particularly prized words -and phrases until they were worn entirely out; and a peculiarity that -conspicuously marked and marred them was the inveterate and intolerable -sermon that wagged its crippled tail at the end of each and every one -of them. No matter what the subject might be, a brain-racking effort -was made to squirm it into some aspect or other that the moral and -religious mind could contemplate with edification. The glaring -insincerity of these sermons was not sufficient to compass the -banishment of the fashion from the schools, and it is not sufficient -to-day; it never will be sufficient while the world stands, perhaps. -There is no school in all our land where the young ladies do not feel -obliged to close their compositions with a sermon; and you will find -that the sermon of the most frivolous and the least religious girl in -the school is always the longest and the most relentlessly pious. But -enough of this. Homely truth is unpalatable. - -Let us return to the "Examination." The first composition that was -read was one entitled "Is this, then, Life?" Perhaps the reader can -endure an extract from it: - - "In the common walks of life, with what delightful - emotions does the youthful mind look forward to some - anticipated scene of festivity! Imagination is busy - sketching rose-tinted pictures of joy. In fancy, the - voluptuous votary of fashion sees herself amid the - festive throng, 'the observed of all observers.' Her - graceful form, arrayed in snowy robes, is whirling - through the mazes of the joyous dance; her eye is - brightest, her step is lightest in the gay assembly. - - "In such delicious fancies time quickly glides by, - and the welcome hour arrives for her entrance into - the Elysian world, of which she has had such bright - dreams. How fairy-like does everything appear to - her enchanted vision! Each new scene is more charming - than the last. But after a while she finds that - beneath this goodly exterior, all is vanity, the - flattery which once charmed her soul, now grates - harshly upon her ear; the ball-room has lost its - charms; and with wasted health and imbittered heart, - she turns away with the conviction that earthly - pleasures cannot satisfy the longings of the soul!" - -And so forth and so on. There was a buzz of gratification from time to -time during the reading, accompanied by whispered ejaculations of "How -sweet!" "How eloquent!" "So true!" etc., and after the thing had closed -with a peculiarly afflicting sermon the applause was enthusiastic. - -Then arose a slim, melancholy girl, whose face had the "interesting" -paleness that comes of pills and indigestion, and read a "poem." Two -stanzas of it will do: - - "A MISSOURI MAIDEN'S FAREWELL TO ALABAMA - - "Alabama, good-bye! I love thee well! - But yet for a while do I leave thee now! - Sad, yes, sad thoughts of thee my heart doth swell, - And burning recollections throng my brow! - For I have wandered through thy flowery woods; - Have roamed and read near Tallapoosa's stream; - Have listened to Tallassee's warring floods, - And wooed on Coosa's side Aurora's beam. - - "Yet shame I not to bear an o'er-full heart, - Nor blush to turn behind my tearful eyes; - 'Tis from no stranger land I now must part, - 'Tis to no strangers left I yield these sighs. - Welcome and home were mine within this State, - Whose vales I leave--whose spires fade fast from me - And cold must be mine eyes, and heart, and tete, - When, dear Alabama! they turn cold on thee!" - -There were very few there who knew what "tete" meant, but the poem was -very satisfactory, nevertheless. - -Next appeared a dark-complexioned, black-eyed, black-haired young -lady, who paused an impressive moment, assumed a tragic expression, and -began to read in a measured, solemn tone: - - "A VISION - - "Dark and tempestuous was night. Around the - throne on high not a single star quivered; but - the deep intonations of the heavy thunder - constantly vibrated upon the ear; whilst the - terrific lightning revelled in angry mood - through the cloudy chambers of heaven, seeming - to scorn the power exerted over its terror by - the illustrious Franklin! Even the boisterous - winds unanimously came forth from their mystic - homes, and blustered about as if to enhance by - their aid the wildness of the scene. - - "At such a time, so dark, so dreary, for human - sympathy my very spirit sighed; but instead thereof, - - "'My dearest friend, my counsellor, my comforter - and guide--My joy in grief, my second bliss - in joy,' came to my side. She moved like one of - those bright beings pictured in the sunny walks - of fancy's Eden by the romantic and young, a - queen of beauty unadorned save by her own - transcendent loveliness. So soft was her step, it - failed to make even a sound, and but for the - magical thrill imparted by her genial touch, as - other unobtrusive beauties, she would have glided - away un-perceived--unsought. A strange sadness - rested upon her features, like icy tears upon - the robe of December, as she pointed to the - contending elements without, and bade me contemplate - the two beings presented." - -This nightmare occupied some ten pages of manuscript and wound up with -a sermon so destructive of all hope to non-Presbyterians that it took -the first prize. This composition was considered to be the very finest -effort of the evening. The mayor of the village, in delivering the -prize to the author of it, made a warm speech in which he said that it -was by far the most "eloquent" thing he had ever listened to, and that -Daniel Webster himself might well be proud of it. - -It may be remarked, in passing, that the number of compositions in -which the word "beauteous" was over-fondled, and human experience -referred to as "life's page," was up to the usual average. - -Now the master, mellow almost to the verge of geniality, put his chair -aside, turned his back to the audience, and began to draw a map of -America on the blackboard, to exercise the geography class upon. But he -made a sad business of it with his unsteady hand, and a smothered -titter rippled over the house. He knew what the matter was, and set -himself to right it. He sponged out lines and remade them; but he only -distorted them more than ever, and the tittering was more pronounced. -He threw his entire attention upon his work, now, as if determined not -to be put down by the mirth. He felt that all eyes were fastened upon -him; he imagined he was succeeding, and yet the tittering continued; it -even manifestly increased. And well it might. There was a garret above, -pierced with a scuttle over his head; and down through this scuttle -came a cat, suspended around the haunches by a string; she had a rag -tied about her head and jaws to keep her from mewing; as she slowly -descended she curved upward and clawed at the string, she swung -downward and clawed at the intangible air. The tittering rose higher -and higher--the cat was within six inches of the absorbed teacher's -head--down, down, a little lower, and she grabbed his wig with her -desperate claws, clung to it, and was snatched up into the garret in an -instant with her trophy still in her possession! And how the light did -blaze abroad from the master's bald pate--for the sign-painter's boy -had GILDED it! - -That broke up the meeting. The boys were avenged. Vacation had come. - - NOTE:--The pretended "compositions" quoted in - this chapter are taken without alteration from a - volume entitled "Prose and Poetry, by a Western - Lady"--but they are exactly and precisely after - the schoolgirl pattern, and hence are much - happier than any mere imitations could be. - - - -CHAPTER XXII - -TOM joined the new order of Cadets of Temperance, being attracted by -the showy character of their "regalia." He promised to abstain from -smoking, chewing, and profanity as long as he remained a member. Now he -found out a new thing--namely, that to promise not to do a thing is the -surest way in the world to make a body want to go and do that very -thing. Tom soon found himself tormented with a desire to drink and -swear; the desire grew to be so intense that nothing but the hope of a -chance to display himself in his red sash kept him from withdrawing -from the order. Fourth of July was coming; but he soon gave that up ---gave it up before he had worn his shackles over forty-eight hours--and -fixed his hopes upon old Judge Frazer, justice of the peace, who was -apparently on his deathbed and would have a big public funeral, since -he was so high an official. During three days Tom was deeply concerned -about the Judge's condition and hungry for news of it. Sometimes his -hopes ran high--so high that he would venture to get out his regalia -and practise before the looking-glass. But the Judge had a most -discouraging way of fluctuating. At last he was pronounced upon the -mend--and then convalescent. Tom was disgusted; and felt a sense of -injury, too. He handed in his resignation at once--and that night the -Judge suffered a relapse and died. Tom resolved that he would never -trust a man like that again. - -The funeral was a fine thing. The Cadets paraded in a style calculated -to kill the late member with envy. Tom was a free boy again, however ---there was something in that. He could drink and swear, now--but found -to his surprise that he did not want to. The simple fact that he could, -took the desire away, and the charm of it. - -Tom presently wondered to find that his coveted vacation was beginning -to hang a little heavily on his hands. - -He attempted a diary--but nothing happened during three days, and so -he abandoned it. - -The first of all the negro minstrel shows came to town, and made a -sensation. Tom and Joe Harper got up a band of performers and were -happy for two days. - -Even the Glorious Fourth was in some sense a failure, for it rained -hard, there was no procession in consequence, and the greatest man in -the world (as Tom supposed), Mr. Benton, an actual United States -Senator, proved an overwhelming disappointment--for he was not -twenty-five feet high, nor even anywhere in the neighborhood of it. - -A circus came. The boys played circus for three days afterward in -tents made of rag carpeting--admission, three pins for boys, two for -girls--and then circusing was abandoned. - -A phrenologist and a mesmerizer came--and went again and left the -village duller and drearier than ever. - -There were some boys-and-girls' parties, but they were so few and so -delightful that they only made the aching voids between ache the harder. - -Becky Thatcher was gone to her Constantinople home to stay with her -parents during vacation--so there was no bright side to life anywhere. - -The dreadful secret of the murder was a chronic misery. It was a very -cancer for permanency and pain. - -Then came the measles. - -During two long weeks Tom lay a prisoner, dead to the world and its -happenings. He was very ill, he was interested in nothing. When he got -upon his feet at last and moved feebly down-town, a melancholy change -had come over everything and every creature. There had been a -"revival," and everybody had "got religion," not only the adults, but -even the boys and girls. Tom went about, hoping against hope for the -sight of one blessed sinful face, but disappointment crossed him -everywhere. He found Joe Harper studying a Testament, and turned sadly -away from the depressing spectacle. He sought Ben Rogers, and found him -visiting the poor with a basket of tracts. He hunted up Jim Hollis, who -called his attention to the precious blessing of his late measles as a -warning. Every boy he encountered added another ton to his depression; -and when, in desperation, he flew for refuge at last to the bosom of -Huckleberry Finn and was received with a Scriptural quotation, his -heart broke and he crept home and to bed realizing that he alone of all -the town was lost, forever and forever. - -And that night there came on a terrific storm, with driving rain, -awful claps of thunder and blinding sheets of lightning. He covered his -head with the bedclothes and waited in a horror of suspense for his -doom; for he had not the shadow of a doubt that all this hubbub was -about him. He believed he had taxed the forbearance of the powers above -to the extremity of endurance and that this was the result. It might -have seemed to him a waste of pomp and ammunition to kill a bug with a -battery of artillery, but there seemed nothing incongruous about the -getting up such an expensive thunderstorm as this to knock the turf -from under an insect like himself. - -By and by the tempest spent itself and died without accomplishing its -object. The boy's first impulse was to be grateful, and reform. His -second was to wait--for there might not be any more storms. - -The next day the doctors were back; Tom had relapsed. The three weeks -he spent on his back this time seemed an entire age. When he got abroad -at last he was hardly grateful that he had been spared, remembering how -lonely was his estate, how companionless and forlorn he was. He drifted -listlessly down the street and found Jim Hollis acting as judge in a -juvenile court that was trying a cat for murder, in the presence of her -victim, a bird. He found Joe Harper and Huck Finn up an alley eating a -stolen melon. Poor lads! they--like Tom--had suffered a relapse. - - - -CHAPTER XXIII - -AT last the sleepy atmosphere was stirred--and vigorously: the murder -trial came on in the court. It became the absorbing topic of village -talk immediately. Tom could not get away from it. Every reference to -the murder sent a shudder to his heart, for his troubled conscience and -fears almost persuaded him that these remarks were put forth in his -hearing as "feelers"; he did not see how he could be suspected of -knowing anything about the murder, but still he could not be -comfortable in the midst of this gossip. It kept him in a cold shiver -all the time. He took Huck to a lonely place to have a talk with him. -It would be some relief to unseal his tongue for a little while; to -divide his burden of distress with another sufferer. Moreover, he -wanted to assure himself that Huck had remained discreet. - -"Huck, have you ever told anybody about--that?" - -"'Bout what?" - -"You know what." - -"Oh--'course I haven't." - -"Never a word?" - -"Never a solitary word, so help me. What makes you ask?" - -"Well, I was afeard." - -"Why, Tom Sawyer, we wouldn't be alive two days if that got found out. -YOU know that." - -Tom felt more comfortable. After a pause: - -"Huck, they couldn't anybody get you to tell, could they?" - -"Get me to tell? Why, if I wanted that half-breed devil to drownd me -they could get me to tell. They ain't no different way." - -"Well, that's all right, then. I reckon we're safe as long as we keep -mum. But let's swear again, anyway. It's more surer." - -"I'm agreed." - -So they swore again with dread solemnities. - -"What is the talk around, Huck? I've heard a power of it." - -"Talk? Well, it's just Muff Potter, Muff Potter, Muff Potter all the -time. It keeps me in a sweat, constant, so's I want to hide som'ers." - -"That's just the same way they go on round me. I reckon he's a goner. -Don't you feel sorry for him, sometimes?" - -"Most always--most always. He ain't no account; but then he hain't -ever done anything to hurt anybody. Just fishes a little, to get money -to get drunk on--and loafs around considerable; but lord, we all do -that--leastways most of us--preachers and such like. But he's kind of -good--he give me half a fish, once, when there warn't enough for two; -and lots of times he's kind of stood by me when I was out of luck." - -"Well, he's mended kites for me, Huck, and knitted hooks on to my -line. I wish we could get him out of there." - -"My! we couldn't get him out, Tom. And besides, 'twouldn't do any -good; they'd ketch him again." - -"Yes--so they would. But I hate to hear 'em abuse him so like the -dickens when he never done--that." - -"I do too, Tom. Lord, I hear 'em say he's the bloodiest looking -villain in this country, and they wonder he wasn't ever hung before." - -"Yes, they talk like that, all the time. I've heard 'em say that if he -was to get free they'd lynch him." - -"And they'd do it, too." - -The boys had a long talk, but it brought them little comfort. As the -twilight drew on, they found themselves hanging about the neighborhood -of the little isolated jail, perhaps with an undefined hope that -something would happen that might clear away their difficulties. But -nothing happened; there seemed to be no angels or fairies interested in -this luckless captive. - -The boys did as they had often done before--went to the cell grating -and gave Potter some tobacco and matches. He was on the ground floor -and there were no guards. - -His gratitude for their gifts had always smote their consciences -before--it cut deeper than ever, this time. They felt cowardly and -treacherous to the last degree when Potter said: - -"You've been mighty good to me, boys--better'n anybody else in this -town. And I don't forget it, I don't. Often I says to myself, says I, -'I used to mend all the boys' kites and things, and show 'em where the -good fishin' places was, and befriend 'em what I could, and now they've -all forgot old Muff when he's in trouble; but Tom don't, and Huck -don't--THEY don't forget him, says I, 'and I don't forget them.' Well, -boys, I done an awful thing--drunk and crazy at the time--that's the -only way I account for it--and now I got to swing for it, and it's -right. Right, and BEST, too, I reckon--hope so, anyway. Well, we won't -talk about that. I don't want to make YOU feel bad; you've befriended -me. But what I want to say, is, don't YOU ever get drunk--then you won't -ever get here. Stand a litter furder west--so--that's it; it's a prime -comfort to see faces that's friendly when a body's in such a muck of -trouble, and there don't none come here but yourn. Good friendly -faces--good friendly faces. Git up on one another's backs and let me -touch 'em. That's it. Shake hands--yourn'll come through the bars, but -mine's too big. Little hands, and weak--but they've helped Muff Potter -a power, and they'd help him more if they could." - -Tom went home miserable, and his dreams that night were full of -horrors. The next day and the day after, he hung about the court-room, -drawn by an almost irresistible impulse to go in, but forcing himself -to stay out. Huck was having the same experience. They studiously -avoided each other. Each wandered away, from time to time, but the same -dismal fascination always brought them back presently. Tom kept his -ears open when idlers sauntered out of the court-room, but invariably -heard distressing news--the toils were closing more and more -relentlessly around poor Potter. At the end of the second day the -village talk was to the effect that Injun Joe's evidence stood firm and -unshaken, and that there was not the slightest question as to what the -jury's verdict would be. - -Tom was out late, that night, and came to bed through the window. He -was in a tremendous state of excitement. It was hours before he got to -sleep. All the village flocked to the court-house the next morning, for -this was to be the great day. Both sexes were about equally represented -in the packed audience. After a long wait the jury filed in and took -their places; shortly afterward, Potter, pale and haggard, timid and -hopeless, was brought in, with chains upon him, and seated where all -the curious eyes could stare at him; no less conspicuous was Injun Joe, -stolid as ever. There was another pause, and then the judge arrived and -the sheriff proclaimed the opening of the court. The usual whisperings -among the lawyers and gathering together of papers followed. These -details and accompanying delays worked up an atmosphere of preparation -that was as impressive as it was fascinating. - -Now a witness was called who testified that he found Muff Potter -washing in the brook, at an early hour of the morning that the murder -was discovered, and that he immediately sneaked away. After some -further questioning, counsel for the prosecution said: - -"Take the witness." - -The prisoner raised his eyes for a moment, but dropped them again when -his own counsel said: - -"I have no questions to ask him." - -The next witness proved the finding of the knife near the corpse. -Counsel for the prosecution said: - -"Take the witness." - -"I have no questions to ask him," Potter's lawyer replied. - -A third witness swore he had often seen the knife in Potter's -possession. - -"Take the witness." - -Counsel for Potter declined to question him. The faces of the audience -began to betray annoyance. Did this attorney mean to throw away his -client's life without an effort? - -Several witnesses deposed concerning Potter's guilty behavior when -brought to the scene of the murder. They were allowed to leave the -stand without being cross-questioned. - -Every detail of the damaging circumstances that occurred in the -graveyard upon that morning which all present remembered so well was -brought out by credible witnesses, but none of them were cross-examined -by Potter's lawyer. The perplexity and dissatisfaction of the house -expressed itself in murmurs and provoked a reproof from the bench. -Counsel for the prosecution now said: - -"By the oaths of citizens whose simple word is above suspicion, we -have fastened this awful crime, beyond all possibility of question, -upon the unhappy prisoner at the bar. We rest our case here." - -A groan escaped from poor Potter, and he put his face in his hands and -rocked his body softly to and fro, while a painful silence reigned in -the court-room. Many men were moved, and many women's compassion -testified itself in tears. Counsel for the defence rose and said: - -"Your honor, in our remarks at the opening of this trial, we -foreshadowed our purpose to prove that our client did this fearful deed -while under the influence of a blind and irresponsible delirium -produced by drink. We have changed our mind. We shall not offer that -plea." [Then to the clerk:] "Call Thomas Sawyer!" - -A puzzled amazement awoke in every face in the house, not even -excepting Potter's. Every eye fastened itself with wondering interest -upon Tom as he rose and took his place upon the stand. The boy looked -wild enough, for he was badly scared. The oath was administered. - -"Thomas Sawyer, where were you on the seventeenth of June, about the -hour of midnight?" - -Tom glanced at Injun Joe's iron face and his tongue failed him. The -audience listened breathless, but the words refused to come. After a -few moments, however, the boy got a little of his strength back, and -managed to put enough of it into his voice to make part of the house -hear: - -"In the graveyard!" - -"A little bit louder, please. Don't be afraid. You were--" - -"In the graveyard." - -A contemptuous smile flitted across Injun Joe's face. - -"Were you anywhere near Horse Williams' grave?" - -"Yes, sir." - -"Speak up--just a trifle louder. How near were you?" - -"Near as I am to you." - -"Were you hidden, or not?" - -"I was hid." - -"Where?" - -"Behind the elms that's on the edge of the grave." - -Injun Joe gave a barely perceptible start. - -"Any one with you?" - -"Yes, sir. I went there with--" - -"Wait--wait a moment. Never mind mentioning your companion's name. We -will produce him at the proper time. Did you carry anything there with -you." - -Tom hesitated and looked confused. - -"Speak out, my boy--don't be diffident. The truth is always -respectable. What did you take there?" - -"Only a--a--dead cat." - -There was a ripple of mirth, which the court checked. - -"We will produce the skeleton of that cat. Now, my boy, tell us -everything that occurred--tell it in your own way--don't skip anything, -and don't be afraid." - -Tom began--hesitatingly at first, but as he warmed to his subject his -words flowed more and more easily; in a little while every sound ceased -but his own voice; every eye fixed itself upon him; with parted lips -and bated breath the audience hung upon his words, taking no note of -time, rapt in the ghastly fascinations of the tale. The strain upon -pent emotion reached its climax when the boy said: - -"--and as the doctor fetched the board around and Muff Potter fell, -Injun Joe jumped with the knife and--" - -Crash! Quick as lightning the half-breed sprang for a window, tore his -way through all opposers, and was gone! - - - -CHAPTER XXIV - -TOM was a glittering hero once more--the pet of the old, the envy of -the young. His name even went into immortal print, for the village -paper magnified him. There were some that believed he would be -President, yet, if he escaped hanging. - -As usual, the fickle, unreasoning world took Muff Potter to its bosom -and fondled him as lavishly as it had abused him before. But that sort -of conduct is to the world's credit; therefore it is not well to find -fault with it. - -Tom's days were days of splendor and exultation to him, but his nights -were seasons of horror. Injun Joe infested all his dreams, and always -with doom in his eye. Hardly any temptation could persuade the boy to -stir abroad after nightfall. Poor Huck was in the same state of -wretchedness and terror, for Tom had told the whole story to the lawyer -the night before the great day of the trial, and Huck was sore afraid -that his share in the business might leak out, yet, notwithstanding -Injun Joe's flight had saved him the suffering of testifying in court. -The poor fellow had got the attorney to promise secrecy, but what of -that? Since Tom's harassed conscience had managed to drive him to the -lawyer's house by night and wring a dread tale from lips that had been -sealed with the dismalest and most formidable of oaths, Huck's -confidence in the human race was well-nigh obliterated. - -Daily Muff Potter's gratitude made Tom glad he had spoken; but nightly -he wished he had sealed up his tongue. - -Half the time Tom was afraid Injun Joe would never be captured; the -other half he was afraid he would be. He felt sure he never could draw -a safe breath again until that man was dead and he had seen the corpse. - -Rewards had been offered, the country had been scoured, but no Injun -Joe was found. One of those omniscient and awe-inspiring marvels, a -detective, came up from St. Louis, moused around, shook his head, -looked wise, and made that sort of astounding success which members of -that craft usually achieve. That is to say, he "found a clew." But you -can't hang a "clew" for murder, and so after that detective had got -through and gone home, Tom felt just as insecure as he was before. - -The slow days drifted on, and each left behind it a slightly lightened -weight of apprehension. - - - -CHAPTER XXV - -THERE comes a time in every rightly-constructed boy's life when he has -a raging desire to go somewhere and dig for hidden treasure. This -desire suddenly came upon Tom one day. He sallied out to find Joe -Harper, but failed of success. Next he sought Ben Rogers; he had gone -fishing. Presently he stumbled upon Huck Finn the Red-Handed. Huck -would answer. Tom took him to a private place and opened the matter to -him confidentially. Huck was willing. Huck was always willing to take a -hand in any enterprise that offered entertainment and required no -capital, for he had a troublesome superabundance of that sort of time -which is not money. "Where'll we dig?" said Huck. - -"Oh, most anywhere." - -"Why, is it hid all around?" - -"No, indeed it ain't. It's hid in mighty particular places, Huck ---sometimes on islands, sometimes in rotten chests under the end of a -limb of an old dead tree, just where the shadow falls at midnight; but -mostly under the floor in ha'nted houses." - -"Who hides it?" - -"Why, robbers, of course--who'd you reckon? Sunday-school -sup'rintendents?" - -"I don't know. If 'twas mine I wouldn't hide it; I'd spend it and have -a good time." - -"So would I. But robbers don't do that way. They always hide it and -leave it there." - -"Don't they come after it any more?" - -"No, they think they will, but they generally forget the marks, or -else they die. Anyway, it lays there a long time and gets rusty; and by -and by somebody finds an old yellow paper that tells how to find the -marks--a paper that's got to be ciphered over about a week because it's -mostly signs and hy'roglyphics." - -"Hyro--which?" - -"Hy'roglyphics--pictures and things, you know, that don't seem to mean -anything." - -"Have you got one of them papers, Tom?" - -"No." - -"Well then, how you going to find the marks?" - -"I don't want any marks. They always bury it under a ha'nted house or -on an island, or under a dead tree that's got one limb sticking out. -Well, we've tried Jackson's Island a little, and we can try it again -some time; and there's the old ha'nted house up the Still-House branch, -and there's lots of dead-limb trees--dead loads of 'em." - -"Is it under all of them?" - -"How you talk! No!" - -"Then how you going to know which one to go for?" - -"Go for all of 'em!" - -"Why, Tom, it'll take all summer." - -"Well, what of that? Suppose you find a brass pot with a hundred -dollars in it, all rusty and gray, or rotten chest full of di'monds. -How's that?" - -Huck's eyes glowed. - -"That's bully. Plenty bully enough for me. Just you gimme the hundred -dollars and I don't want no di'monds." - -"All right. But I bet you I ain't going to throw off on di'monds. Some -of 'em's worth twenty dollars apiece--there ain't any, hardly, but's -worth six bits or a dollar." - -"No! Is that so?" - -"Cert'nly--anybody'll tell you so. Hain't you ever seen one, Huck?" - -"Not as I remember." - -"Oh, kings have slathers of them." - -"Well, I don' know no kings, Tom." - -"I reckon you don't. But if you was to go to Europe you'd see a raft -of 'em hopping around." - -"Do they hop?" - -"Hop?--your granny! No!" - -"Well, what did you say they did, for?" - -"Shucks, I only meant you'd SEE 'em--not hopping, of course--what do -they want to hop for?--but I mean you'd just see 'em--scattered around, -you know, in a kind of a general way. Like that old humpbacked Richard." - -"Richard? What's his other name?" - -"He didn't have any other name. Kings don't have any but a given name." - -"No?" - -"But they don't." - -"Well, if they like it, Tom, all right; but I don't want to be a king -and have only just a given name, like a nigger. But say--where you -going to dig first?" - -"Well, I don't know. S'pose we tackle that old dead-limb tree on the -hill t'other side of Still-House branch?" - -"I'm agreed." - -So they got a crippled pick and a shovel, and set out on their -three-mile tramp. They arrived hot and panting, and threw themselves -down in the shade of a neighboring elm to rest and have a smoke. - -"I like this," said Tom. - -"So do I." - -"Say, Huck, if we find a treasure here, what you going to do with your -share?" - -"Well, I'll have pie and a glass of soda every day, and I'll go to -every circus that comes along. I bet I'll have a gay time." - -"Well, ain't you going to save any of it?" - -"Save it? What for?" - -"Why, so as to have something to live on, by and by." - -"Oh, that ain't any use. Pap would come back to thish-yer town some -day and get his claws on it if I didn't hurry up, and I tell you he'd -clean it out pretty quick. What you going to do with yourn, Tom?" - -"I'm going to buy a new drum, and a sure-'nough sword, and a red -necktie and a bull pup, and get married." - -"Married!" - -"That's it." - -"Tom, you--why, you ain't in your right mind." - -"Wait--you'll see." - -"Well, that's the foolishest thing you could do. Look at pap and my -mother. Fight! Why, they used to fight all the time. I remember, mighty -well." - -"That ain't anything. The girl I'm going to marry won't fight." - -"Tom, I reckon they're all alike. They'll all comb a body. Now you -better think 'bout this awhile. I tell you you better. What's the name -of the gal?" - -"It ain't a gal at all--it's a girl." - -"It's all the same, I reckon; some says gal, some says girl--both's -right, like enough. Anyway, what's her name, Tom?" - -"I'll tell you some time--not now." - -"All right--that'll do. Only if you get married I'll be more lonesomer -than ever." - -"No you won't. You'll come and live with me. Now stir out of this and -we'll go to digging." - -They worked and sweated for half an hour. No result. They toiled -another half-hour. Still no result. Huck said: - -"Do they always bury it as deep as this?" - -"Sometimes--not always. Not generally. I reckon we haven't got the -right place." - -So they chose a new spot and began again. The labor dragged a little, -but still they made progress. They pegged away in silence for some -time. Finally Huck leaned on his shovel, swabbed the beaded drops from -his brow with his sleeve, and said: - -"Where you going to dig next, after we get this one?" - -"I reckon maybe we'll tackle the old tree that's over yonder on -Cardiff Hill back of the widow's." - -"I reckon that'll be a good one. But won't the widow take it away from -us, Tom? It's on her land." - -"SHE take it away! Maybe she'd like to try it once. Whoever finds one -of these hid treasures, it belongs to him. It don't make any difference -whose land it's on." - -That was satisfactory. The work went on. By and by Huck said: - -"Blame it, we must be in the wrong place again. What do you think?" - -"It is mighty curious, Huck. I don't understand it. Sometimes witches -interfere. I reckon maybe that's what's the trouble now." - -"Shucks! Witches ain't got no power in the daytime." - -"Well, that's so. I didn't think of that. Oh, I know what the matter -is! What a blamed lot of fools we are! You got to find out where the -shadow of the limb falls at midnight, and that's where you dig!" - -"Then consound it, we've fooled away all this work for nothing. Now -hang it all, we got to come back in the night. It's an awful long way. -Can you get out?" - -"I bet I will. We've got to do it to-night, too, because if somebody -sees these holes they'll know in a minute what's here and they'll go -for it." - -"Well, I'll come around and maow to-night." - -"All right. Let's hide the tools in the bushes." - -The boys were there that night, about the appointed time. They sat in -the shadow waiting. It was a lonely place, and an hour made solemn by -old traditions. Spirits whispered in the rustling leaves, ghosts lurked -in the murky nooks, the deep baying of a hound floated up out of the -distance, an owl answered with his sepulchral note. The boys were -subdued by these solemnities, and talked little. By and by they judged -that twelve had come; they marked where the shadow fell, and began to -dig. Their hopes commenced to rise. Their interest grew stronger, and -their industry kept pace with it. The hole deepened and still deepened, -but every time their hearts jumped to hear the pick strike upon -something, they only suffered a new disappointment. It was only a stone -or a chunk. At last Tom said: - -"It ain't any use, Huck, we're wrong again." - -"Well, but we CAN'T be wrong. We spotted the shadder to a dot." - -"I know it, but then there's another thing." - -"What's that?". - -"Why, we only guessed at the time. Like enough it was too late or too -early." - -Huck dropped his shovel. - -"That's it," said he. "That's the very trouble. We got to give this -one up. We can't ever tell the right time, and besides this kind of -thing's too awful, here this time of night with witches and ghosts -a-fluttering around so. I feel as if something's behind me all the time; -and I'm afeard to turn around, becuz maybe there's others in front -a-waiting for a chance. I been creeping all over, ever since I got here." - -"Well, I've been pretty much so, too, Huck. They most always put in a -dead man when they bury a treasure under a tree, to look out for it." - -"Lordy!" - -"Yes, they do. I've always heard that." - -"Tom, I don't like to fool around much where there's dead people. A -body's bound to get into trouble with 'em, sure." - -"I don't like to stir 'em up, either. S'pose this one here was to -stick his skull out and say something!" - -"Don't Tom! It's awful." - -"Well, it just is. Huck, I don't feel comfortable a bit." - -"Say, Tom, let's give this place up, and try somewheres else." - -"All right, I reckon we better." - -"What'll it be?" - -Tom considered awhile; and then said: - -"The ha'nted house. That's it!" - -"Blame it, I don't like ha'nted houses, Tom. Why, they're a dern sight -worse'n dead people. Dead people might talk, maybe, but they don't come -sliding around in a shroud, when you ain't noticing, and peep over your -shoulder all of a sudden and grit their teeth, the way a ghost does. I -couldn't stand such a thing as that, Tom--nobody could." - -"Yes, but, Huck, ghosts don't travel around only at night. They won't -hender us from digging there in the daytime." - -"Well, that's so. But you know mighty well people don't go about that -ha'nted house in the day nor the night." - -"Well, that's mostly because they don't like to go where a man's been -murdered, anyway--but nothing's ever been seen around that house except -in the night--just some blue lights slipping by the windows--no regular -ghosts." - -"Well, where you see one of them blue lights flickering around, Tom, -you can bet there's a ghost mighty close behind it. It stands to -reason. Becuz you know that they don't anybody but ghosts use 'em." - -"Yes, that's so. But anyway they don't come around in the daytime, so -what's the use of our being afeard?" - -"Well, all right. We'll tackle the ha'nted house if you say so--but I -reckon it's taking chances." - -They had started down the hill by this time. There in the middle of -the moonlit valley below them stood the "ha'nted" house, utterly -isolated, its fences gone long ago, rank weeds smothering the very -doorsteps, the chimney crumbled to ruin, the window-sashes vacant, a -corner of the roof caved in. The boys gazed awhile, half expecting to -see a blue light flit past a window; then talking in a low tone, as -befitted the time and the circumstances, they struck far off to the -right, to give the haunted house a wide berth, and took their way -homeward through the woods that adorned the rearward side of Cardiff -Hill. - - - -CHAPTER XXVI - -ABOUT noon the next day the boys arrived at the dead tree; they had -come for their tools. Tom was impatient to go to the haunted house; -Huck was measurably so, also--but suddenly said: - -"Lookyhere, Tom, do you know what day it is?" - -Tom mentally ran over the days of the week, and then quickly lifted -his eyes with a startled look in them-- - -"My! I never once thought of it, Huck!" - -"Well, I didn't neither, but all at once it popped onto me that it was -Friday." - -"Blame it, a body can't be too careful, Huck. We might 'a' got into an -awful scrape, tackling such a thing on a Friday." - -"MIGHT! Better say we WOULD! There's some lucky days, maybe, but -Friday ain't." - -"Any fool knows that. I don't reckon YOU was the first that found it -out, Huck." - -"Well, I never said I was, did I? And Friday ain't all, neither. I had -a rotten bad dream last night--dreampt about rats." - -"No! Sure sign of trouble. Did they fight?" - -"No." - -"Well, that's good, Huck. When they don't fight it's only a sign that -there's trouble around, you know. All we got to do is to look mighty -sharp and keep out of it. We'll drop this thing for to-day, and play. -Do you know Robin Hood, Huck?" - -"No. Who's Robin Hood?" - -"Why, he was one of the greatest men that was ever in England--and the -best. He was a robber." - -"Cracky, I wisht I was. Who did he rob?" - -"Only sheriffs and bishops and rich people and kings, and such like. -But he never bothered the poor. He loved 'em. He always divided up with -'em perfectly square." - -"Well, he must 'a' been a brick." - -"I bet you he was, Huck. Oh, he was the noblest man that ever was. -They ain't any such men now, I can tell you. He could lick any man in -England, with one hand tied behind him; and he could take his yew bow -and plug a ten-cent piece every time, a mile and a half." - -"What's a YEW bow?" - -"I don't know. It's some kind of a bow, of course. And if he hit that -dime only on the edge he would set down and cry--and curse. But we'll -play Robin Hood--it's nobby fun. I'll learn you." - -"I'm agreed." - -So they played Robin Hood all the afternoon, now and then casting a -yearning eye down upon the haunted house and passing a remark about the -morrow's prospects and possibilities there. As the sun began to sink -into the west they took their way homeward athwart the long shadows of -the trees and soon were buried from sight in the forests of Cardiff -Hill. - -On Saturday, shortly after noon, the boys were at the dead tree again. -They had a smoke and a chat in the shade, and then dug a little in -their last hole, not with great hope, but merely because Tom said there -were so many cases where people had given up a treasure after getting -down within six inches of it, and then somebody else had come along and -turned it up with a single thrust of a shovel. The thing failed this -time, however, so the boys shouldered their tools and went away feeling -that they had not trifled with fortune, but had fulfilled all the -requirements that belong to the business of treasure-hunting. - -When they reached the haunted house there was something so weird and -grisly about the dead silence that reigned there under the baking sun, -and something so depressing about the loneliness and desolation of the -place, that they were afraid, for a moment, to venture in. Then they -crept to the door and took a trembling peep. They saw a weed-grown, -floorless room, unplastered, an ancient fireplace, vacant windows, a -ruinous staircase; and here, there, and everywhere hung ragged and -abandoned cobwebs. They presently entered, softly, with quickened -pulses, talking in whispers, ears alert to catch the slightest sound, -and muscles tense and ready for instant retreat. - -In a little while familiarity modified their fears and they gave the -place a critical and interested examination, rather admiring their own -boldness, and wondering at it, too. Next they wanted to look up-stairs. -This was something like cutting off retreat, but they got to daring -each other, and of course there could be but one result--they threw -their tools into a corner and made the ascent. Up there were the same -signs of decay. In one corner they found a closet that promised -mystery, but the promise was a fraud--there was nothing in it. Their -courage was up now and well in hand. They were about to go down and -begin work when-- - -"Sh!" said Tom. - -"What is it?" whispered Huck, blanching with fright. - -"Sh!... There!... Hear it?" - -"Yes!... Oh, my! Let's run!" - -"Keep still! Don't you budge! They're coming right toward the door." - -The boys stretched themselves upon the floor with their eyes to -knot-holes in the planking, and lay waiting, in a misery of fear. - -"They've stopped.... No--coming.... Here they are. Don't whisper -another word, Huck. My goodness, I wish I was out of this!" - -Two men entered. Each boy said to himself: "There's the old deaf and -dumb Spaniard that's been about town once or twice lately--never saw -t'other man before." - -"T'other" was a ragged, unkempt creature, with nothing very pleasant -in his face. The Spaniard was wrapped in a serape; he had bushy white -whiskers; long white hair flowed from under his sombrero, and he wore -green goggles. When they came in, "t'other" was talking in a low voice; -they sat down on the ground, facing the door, with their backs to the -wall, and the speaker continued his remarks. His manner became less -guarded and his words more distinct as he proceeded: - -"No," said he, "I've thought it all over, and I don't like it. It's -dangerous." - -"Dangerous!" grunted the "deaf and dumb" Spaniard--to the vast -surprise of the boys. "Milksop!" - -This voice made the boys gasp and quake. It was Injun Joe's! There was -silence for some time. Then Joe said: - -"What's any more dangerous than that job up yonder--but nothing's come -of it." - -"That's different. Away up the river so, and not another house about. -'Twon't ever be known that we tried, anyway, long as we didn't succeed." - -"Well, what's more dangerous than coming here in the daytime!--anybody -would suspicion us that saw us." - -"I know that. But there warn't any other place as handy after that -fool of a job. I want to quit this shanty. I wanted to yesterday, only -it warn't any use trying to stir out of here, with those infernal boys -playing over there on the hill right in full view." - -"Those infernal boys" quaked again under the inspiration of this -remark, and thought how lucky it was that they had remembered it was -Friday and concluded to wait a day. They wished in their hearts they -had waited a year. - -The two men got out some food and made a luncheon. After a long and -thoughtful silence, Injun Joe said: - -"Look here, lad--you go back up the river where you belong. Wait there -till you hear from me. I'll take the chances on dropping into this town -just once more, for a look. We'll do that 'dangerous' job after I've -spied around a little and think things look well for it. Then for -Texas! We'll leg it together!" - -This was satisfactory. Both men presently fell to yawning, and Injun -Joe said: - -"I'm dead for sleep! It's your turn to watch." - -He curled down in the weeds and soon began to snore. His comrade -stirred him once or twice and he became quiet. Presently the watcher -began to nod; his head drooped lower and lower, both men began to snore -now. - -The boys drew a long, grateful breath. Tom whispered: - -"Now's our chance--come!" - -Huck said: - -"I can't--I'd die if they was to wake." - -Tom urged--Huck held back. At last Tom rose slowly and softly, and -started alone. But the first step he made wrung such a hideous creak -from the crazy floor that he sank down almost dead with fright. He -never made a second attempt. The boys lay there counting the dragging -moments till it seemed to them that time must be done and eternity -growing gray; and then they were grateful to note that at last the sun -was setting. - -Now one snore ceased. Injun Joe sat up, stared around--smiled grimly -upon his comrade, whose head was drooping upon his knees--stirred him -up with his foot and said: - -"Here! YOU'RE a watchman, ain't you! All right, though--nothing's -happened." - -"My! have I been asleep?" - -"Oh, partly, partly. Nearly time for us to be moving, pard. What'll we -do with what little swag we've got left?" - -"I don't know--leave it here as we've always done, I reckon. No use to -take it away till we start south. Six hundred and fifty in silver's -something to carry." - -"Well--all right--it won't matter to come here once more." - -"No--but I'd say come in the night as we used to do--it's better." - -"Yes: but look here; it may be a good while before I get the right -chance at that job; accidents might happen; 'tain't in such a very good -place; we'll just regularly bury it--and bury it deep." - -"Good idea," said the comrade, who walked across the room, knelt down, -raised one of the rearward hearth-stones and took out a bag that -jingled pleasantly. He subtracted from it twenty or thirty dollars for -himself and as much for Injun Joe, and passed the bag to the latter, -who was on his knees in the corner, now, digging with his bowie-knife. - -The boys forgot all their fears, all their miseries in an instant. -With gloating eyes they watched every movement. Luck!--the splendor of -it was beyond all imagination! Six hundred dollars was money enough to -make half a dozen boys rich! Here was treasure-hunting under the -happiest auspices--there would not be any bothersome uncertainty as to -where to dig. They nudged each other every moment--eloquent nudges and -easily understood, for they simply meant--"Oh, but ain't you glad NOW -we're here!" - -Joe's knife struck upon something. - -"Hello!" said he. - -"What is it?" said his comrade. - -"Half-rotten plank--no, it's a box, I believe. Here--bear a hand and -we'll see what it's here for. Never mind, I've broke a hole." - -He reached his hand in and drew it out-- - -"Man, it's money!" - -The two men examined the handful of coins. They were gold. The boys -above were as excited as themselves, and as delighted. - -Joe's comrade said: - -"We'll make quick work of this. There's an old rusty pick over amongst -the weeds in the corner the other side of the fireplace--I saw it a -minute ago." - -He ran and brought the boys' pick and shovel. Injun Joe took the pick, -looked it over critically, shook his head, muttered something to -himself, and then began to use it. The box was soon unearthed. It was -not very large; it was iron bound and had been very strong before the -slow years had injured it. The men contemplated the treasure awhile in -blissful silence. - -"Pard, there's thousands of dollars here," said Injun Joe. - -"'Twas always said that Murrel's gang used to be around here one -summer," the stranger observed. - -"I know it," said Injun Joe; "and this looks like it, I should say." - -"Now you won't need to do that job." - -The half-breed frowned. Said he: - -"You don't know me. Least you don't know all about that thing. 'Tain't -robbery altogether--it's REVENGE!" and a wicked light flamed in his -eyes. "I'll need your help in it. When it's finished--then Texas. Go -home to your Nance and your kids, and stand by till you hear from me." - -"Well--if you say so; what'll we do with this--bury it again?" - -"Yes. [Ravishing delight overhead.] NO! by the great Sachem, no! -[Profound distress overhead.] I'd nearly forgot. That pick had fresh -earth on it! [The boys were sick with terror in a moment.] What -business has a pick and a shovel here? What business with fresh earth -on them? Who brought them here--and where are they gone? Have you heard -anybody?--seen anybody? What! bury it again and leave them to come and -see the ground disturbed? Not exactly--not exactly. We'll take it to my -den." - -"Why, of course! Might have thought of that before. You mean Number -One?" - -"No--Number Two--under the cross. The other place is bad--too common." - -"All right. It's nearly dark enough to start." - -Injun Joe got up and went about from window to window cautiously -peeping out. Presently he said: - -"Who could have brought those tools here? Do you reckon they can be -up-stairs?" - -The boys' breath forsook them. Injun Joe put his hand on his knife, -halted a moment, undecided, and then turned toward the stairway. The -boys thought of the closet, but their strength was gone. The steps came -creaking up the stairs--the intolerable distress of the situation woke -the stricken resolution of the lads--they were about to spring for the -closet, when there was a crash of rotten timbers and Injun Joe landed -on the ground amid the debris of the ruined stairway. He gathered -himself up cursing, and his comrade said: - -"Now what's the use of all that? If it's anybody, and they're up -there, let them STAY there--who cares? If they want to jump down, now, -and get into trouble, who objects? It will be dark in fifteen minutes ---and then let them follow us if they want to. I'm willing. In my -opinion, whoever hove those things in here caught a sight of us and -took us for ghosts or devils or something. I'll bet they're running -yet." - -Joe grumbled awhile; then he agreed with his friend that what daylight -was left ought to be economized in getting things ready for leaving. -Shortly afterward they slipped out of the house in the deepening -twilight, and moved toward the river with their precious box. - -Tom and Huck rose up, weak but vastly relieved, and stared after them -through the chinks between the logs of the house. Follow? Not they. -They were content to reach ground again without broken necks, and take -the townward track over the hill. They did not talk much. They were too -much absorbed in hating themselves--hating the ill luck that made them -take the spade and the pick there. But for that, Injun Joe never would -have suspected. He would have hidden the silver with the gold to wait -there till his "revenge" was satisfied, and then he would have had the -misfortune to find that money turn up missing. Bitter, bitter luck that -the tools were ever brought there! - -They resolved to keep a lookout for that Spaniard when he should come -to town spying out for chances to do his revengeful job, and follow him -to "Number Two," wherever that might be. Then a ghastly thought -occurred to Tom. - -"Revenge? What if he means US, Huck!" - -"Oh, don't!" said Huck, nearly fainting. - -They talked it all over, and as they entered town they agreed to -believe that he might possibly mean somebody else--at least that he -might at least mean nobody but Tom, since only Tom had testified. - -Very, very small comfort it was to Tom to be alone in danger! Company -would be a palpable improvement, he thought. - - - -CHAPTER XXVII - -THE adventure of the day mightily tormented Tom's dreams that night. -Four times he had his hands on that rich treasure and four times it -wasted to nothingness in his fingers as sleep forsook him and -wakefulness brought back the hard reality of his misfortune. As he lay -in the early morning recalling the incidents of his great adventure, he -noticed that they seemed curiously subdued and far away--somewhat as if -they had happened in another world, or in a time long gone by. Then it -occurred to him that the great adventure itself must be a dream! There -was one very strong argument in favor of this idea--namely, that the -quantity of coin he had seen was too vast to be real. He had never seen -as much as fifty dollars in one mass before, and he was like all boys -of his age and station in life, in that he imagined that all references -to "hundreds" and "thousands" were mere fanciful forms of speech, and -that no such sums really existed in the world. He never had supposed -for a moment that so large a sum as a hundred dollars was to be found -in actual money in any one's possession. If his notions of hidden -treasure had been analyzed, they would have been found to consist of a -handful of real dimes and a bushel of vague, splendid, ungraspable -dollars. - -But the incidents of his adventure grew sensibly sharper and clearer -under the attrition of thinking them over, and so he presently found -himself leaning to the impression that the thing might not have been a -dream, after all. This uncertainty must be swept away. He would snatch -a hurried breakfast and go and find Huck. Huck was sitting on the -gunwale of a flatboat, listlessly dangling his feet in the water and -looking very melancholy. Tom concluded to let Huck lead up to the -subject. If he did not do it, then the adventure would be proved to -have been only a dream. - -"Hello, Huck!" - -"Hello, yourself." - -Silence, for a minute. - -"Tom, if we'd 'a' left the blame tools at the dead tree, we'd 'a' got -the money. Oh, ain't it awful!" - -"'Tain't a dream, then, 'tain't a dream! Somehow I most wish it was. -Dog'd if I don't, Huck." - -"What ain't a dream?" - -"Oh, that thing yesterday. I been half thinking it was." - -"Dream! If them stairs hadn't broke down you'd 'a' seen how much dream -it was! I've had dreams enough all night--with that patch-eyed Spanish -devil going for me all through 'em--rot him!" - -"No, not rot him. FIND him! Track the money!" - -"Tom, we'll never find him. A feller don't have only one chance for -such a pile--and that one's lost. I'd feel mighty shaky if I was to see -him, anyway." - -"Well, so'd I; but I'd like to see him, anyway--and track him out--to -his Number Two." - -"Number Two--yes, that's it. I been thinking 'bout that. But I can't -make nothing out of it. What do you reckon it is?" - -"I dono. It's too deep. Say, Huck--maybe it's the number of a house!" - -"Goody!... No, Tom, that ain't it. If it is, it ain't in this -one-horse town. They ain't no numbers here." - -"Well, that's so. Lemme think a minute. Here--it's the number of a -room--in a tavern, you know!" - -"Oh, that's the trick! They ain't only two taverns. We can find out -quick." - -"You stay here, Huck, till I come." - -Tom was off at once. He did not care to have Huck's company in public -places. He was gone half an hour. He found that in the best tavern, No. -2 had long been occupied by a young lawyer, and was still so occupied. -In the less ostentatious house, No. 2 was a mystery. The -tavern-keeper's young son said it was kept locked all the time, and he -never saw anybody go into it or come out of it except at night; he did -not know any particular reason for this state of things; had had some -little curiosity, but it was rather feeble; had made the most of the -mystery by entertaining himself with the idea that that room was -"ha'nted"; had noticed that there was a light in there the night before. - -"That's what I've found out, Huck. I reckon that's the very No. 2 -we're after." - -"I reckon it is, Tom. Now what you going to do?" - -"Lemme think." - -Tom thought a long time. Then he said: - -"I'll tell you. The back door of that No. 2 is the door that comes out -into that little close alley between the tavern and the old rattle trap -of a brick store. Now you get hold of all the door-keys you can find, -and I'll nip all of auntie's, and the first dark night we'll go there -and try 'em. And mind you, keep a lookout for Injun Joe, because he -said he was going to drop into town and spy around once more for a -chance to get his revenge. If you see him, you just follow him; and if -he don't go to that No. 2, that ain't the place." - -"Lordy, I don't want to foller him by myself!" - -"Why, it'll be night, sure. He mightn't ever see you--and if he did, -maybe he'd never think anything." - -"Well, if it's pretty dark I reckon I'll track him. I dono--I dono. -I'll try." - -"You bet I'll follow him, if it's dark, Huck. Why, he might 'a' found -out he couldn't get his revenge, and be going right after that money." - -"It's so, Tom, it's so. I'll foller him; I will, by jingoes!" - -"Now you're TALKING! Don't you ever weaken, Huck, and I won't." - - - -CHAPTER XXVIII - -THAT night Tom and Huck were ready for their adventure. They hung -about the neighborhood of the tavern until after nine, one watching the -alley at a distance and the other the tavern door. Nobody entered the -alley or left it; nobody resembling the Spaniard entered or left the -tavern door. The night promised to be a fair one; so Tom went home with -the understanding that if a considerable degree of darkness came on, -Huck was to come and "maow," whereupon he would slip out and try the -keys. But the night remained clear, and Huck closed his watch and -retired to bed in an empty sugar hogshead about twelve. - -Tuesday the boys had the same ill luck. Also Wednesday. But Thursday -night promised better. Tom slipped out in good season with his aunt's -old tin lantern, and a large towel to blindfold it with. He hid the -lantern in Huck's sugar hogshead and the watch began. An hour before -midnight the tavern closed up and its lights (the only ones -thereabouts) were put out. No Spaniard had been seen. Nobody had -entered or left the alley. Everything was auspicious. The blackness of -darkness reigned, the perfect stillness was interrupted only by -occasional mutterings of distant thunder. - -Tom got his lantern, lit it in the hogshead, wrapped it closely in the -towel, and the two adventurers crept in the gloom toward the tavern. -Huck stood sentry and Tom felt his way into the alley. Then there was a -season of waiting anxiety that weighed upon Huck's spirits like a -mountain. He began to wish he could see a flash from the lantern--it -would frighten him, but it would at least tell him that Tom was alive -yet. It seemed hours since Tom had disappeared. Surely he must have -fainted; maybe he was dead; maybe his heart had burst under terror and -excitement. In his uneasiness Huck found himself drawing closer and -closer to the alley; fearing all sorts of dreadful things, and -momentarily expecting some catastrophe to happen that would take away -his breath. There was not much to take away, for he seemed only able to -inhale it by thimblefuls, and his heart would soon wear itself out, the -way it was beating. Suddenly there was a flash of light and Tom came -tearing by him: "Run!" said he; "run, for your life!" - -He needn't have repeated it; once was enough; Huck was making thirty -or forty miles an hour before the repetition was uttered. The boys -never stopped till they reached the shed of a deserted slaughter-house -at the lower end of the village. Just as they got within its shelter -the storm burst and the rain poured down. As soon as Tom got his breath -he said: - -"Huck, it was awful! I tried two of the keys, just as soft as I could; -but they seemed to make such a power of racket that I couldn't hardly -get my breath I was so scared. They wouldn't turn in the lock, either. -Well, without noticing what I was doing, I took hold of the knob, and -open comes the door! It warn't locked! I hopped in, and shook off the -towel, and, GREAT CAESAR'S GHOST!" - -"What!--what'd you see, Tom?" - -"Huck, I most stepped onto Injun Joe's hand!" - -"No!" - -"Yes! He was lying there, sound asleep on the floor, with his old -patch on his eye and his arms spread out." - -"Lordy, what did you do? Did he wake up?" - -"No, never budged. Drunk, I reckon. I just grabbed that towel and -started!" - -"I'd never 'a' thought of the towel, I bet!" - -"Well, I would. My aunt would make me mighty sick if I lost it." - -"Say, Tom, did you see that box?" - -"Huck, I didn't wait to look around. I didn't see the box, I didn't -see the cross. I didn't see anything but a bottle and a tin cup on the -floor by Injun Joe; yes, I saw two barrels and lots more bottles in the -room. Don't you see, now, what's the matter with that ha'nted room?" - -"How?" - -"Why, it's ha'nted with whiskey! Maybe ALL the Temperance Taverns have -got a ha'nted room, hey, Huck?" - -"Well, I reckon maybe that's so. Who'd 'a' thought such a thing? But -say, Tom, now's a mighty good time to get that box, if Injun Joe's -drunk." - -"It is, that! You try it!" - -Huck shuddered. - -"Well, no--I reckon not." - -"And I reckon not, Huck. Only one bottle alongside of Injun Joe ain't -enough. If there'd been three, he'd be drunk enough and I'd do it." - -There was a long pause for reflection, and then Tom said: - -"Lookyhere, Huck, less not try that thing any more till we know Injun -Joe's not in there. It's too scary. Now, if we watch every night, we'll -be dead sure to see him go out, some time or other, and then we'll -snatch that box quicker'n lightning." - -"Well, I'm agreed. I'll watch the whole night long, and I'll do it -every night, too, if you'll do the other part of the job." - -"All right, I will. All you got to do is to trot up Hooper Street a -block and maow--and if I'm asleep, you throw some gravel at the window -and that'll fetch me." - -"Agreed, and good as wheat!" - -"Now, Huck, the storm's over, and I'll go home. It'll begin to be -daylight in a couple of hours. You go back and watch that long, will -you?" - -"I said I would, Tom, and I will. I'll ha'nt that tavern every night -for a year! I'll sleep all day and I'll stand watch all night." - -"That's all right. Now, where you going to sleep?" - -"In Ben Rogers' hayloft. He lets me, and so does his pap's nigger man, -Uncle Jake. I tote water for Uncle Jake whenever he wants me to, and -any time I ask him he gives me a little something to eat if he can -spare it. That's a mighty good nigger, Tom. He likes me, becuz I don't -ever act as if I was above him. Sometime I've set right down and eat -WITH him. But you needn't tell that. A body's got to do things when -he's awful hungry he wouldn't want to do as a steady thing." - -"Well, if I don't want you in the daytime, I'll let you sleep. I won't -come bothering around. Any time you see something's up, in the night, -just skip right around and maow." - - - -CHAPTER XXIX - -THE first thing Tom heard on Friday morning was a glad piece of news ---Judge Thatcher's family had come back to town the night before. Both -Injun Joe and the treasure sunk into secondary importance for a moment, -and Becky took the chief place in the boy's interest. He saw her and -they had an exhausting good time playing "hi-spy" and "gully-keeper" -with a crowd of their school-mates. The day was completed and crowned -in a peculiarly satisfactory way: Becky teased her mother to appoint -the next day for the long-promised and long-delayed picnic, and she -consented. The child's delight was boundless; and Tom's not more -moderate. The invitations were sent out before sunset, and straightway -the young folks of the village were thrown into a fever of preparation -and pleasurable anticipation. Tom's excitement enabled him to keep -awake until a pretty late hour, and he had good hopes of hearing Huck's -"maow," and of having his treasure to astonish Becky and the picnickers -with, next day; but he was disappointed. No signal came that night. - -Morning came, eventually, and by ten or eleven o'clock a giddy and -rollicking company were gathered at Judge Thatcher's, and everything -was ready for a start. It was not the custom for elderly people to mar -the picnics with their presence. The children were considered safe -enough under the wings of a few young ladies of eighteen and a few -young gentlemen of twenty-three or thereabouts. The old steam ferryboat -was chartered for the occasion; presently the gay throng filed up the -main street laden with provision-baskets. Sid was sick and had to miss -the fun; Mary remained at home to entertain him. The last thing Mrs. -Thatcher said to Becky, was: - -"You'll not get back till late. Perhaps you'd better stay all night -with some of the girls that live near the ferry-landing, child." - -"Then I'll stay with Susy Harper, mamma." - -"Very well. And mind and behave yourself and don't be any trouble." - -Presently, as they tripped along, Tom said to Becky: - -"Say--I'll tell you what we'll do. 'Stead of going to Joe Harper's -we'll climb right up the hill and stop at the Widow Douglas'. She'll -have ice-cream! She has it most every day--dead loads of it. And she'll -be awful glad to have us." - -"Oh, that will be fun!" - -Then Becky reflected a moment and said: - -"But what will mamma say?" - -"How'll she ever know?" - -The girl turned the idea over in her mind, and said reluctantly: - -"I reckon it's wrong--but--" - -"But shucks! Your mother won't know, and so what's the harm? All she -wants is that you'll be safe; and I bet you she'd 'a' said go there if -she'd 'a' thought of it. I know she would!" - -The Widow Douglas' splendid hospitality was a tempting bait. It and -Tom's persuasions presently carried the day. So it was decided to say -nothing anybody about the night's programme. Presently it occurred to -Tom that maybe Huck might come this very night and give the signal. The -thought took a deal of the spirit out of his anticipations. Still he -could not bear to give up the fun at Widow Douglas'. And why should he -give it up, he reasoned--the signal did not come the night before, so -why should it be any more likely to come to-night? The sure fun of the -evening outweighed the uncertain treasure; and, boy-like, he determined -to yield to the stronger inclination and not allow himself to think of -the box of money another time that day. - -Three miles below town the ferryboat stopped at the mouth of a woody -hollow and tied up. The crowd swarmed ashore and soon the forest -distances and craggy heights echoed far and near with shoutings and -laughter. All the different ways of getting hot and tired were gone -through with, and by-and-by the rovers straggled back to camp fortified -with responsible appetites, and then the destruction of the good things -began. After the feast there was a refreshing season of rest and chat -in the shade of spreading oaks. By-and-by somebody shouted: - -"Who's ready for the cave?" - -Everybody was. Bundles of candles were procured, and straightway there -was a general scamper up the hill. The mouth of the cave was up the -hillside--an opening shaped like a letter A. Its massive oaken door -stood unbarred. Within was a small chamber, chilly as an ice-house, and -walled by Nature with solid limestone that was dewy with a cold sweat. -It was romantic and mysterious to stand here in the deep gloom and look -out upon the green valley shining in the sun. But the impressiveness of -the situation quickly wore off, and the romping began again. The moment -a candle was lighted there was a general rush upon the owner of it; a -struggle and a gallant defence followed, but the candle was soon -knocked down or blown out, and then there was a glad clamor of laughter -and a new chase. But all things have an end. By-and-by the procession -went filing down the steep descent of the main avenue, the flickering -rank of lights dimly revealing the lofty walls of rock almost to their -point of junction sixty feet overhead. This main avenue was not more -than eight or ten feet wide. Every few steps other lofty and still -narrower crevices branched from it on either hand--for McDougal's cave -was but a vast labyrinth of crooked aisles that ran into each other and -out again and led nowhere. It was said that one might wander days and -nights together through its intricate tangle of rifts and chasms, and -never find the end of the cave; and that he might go down, and down, -and still down, into the earth, and it was just the same--labyrinth -under labyrinth, and no end to any of them. No man "knew" the cave. -That was an impossible thing. Most of the young men knew a portion of -it, and it was not customary to venture much beyond this known portion. -Tom Sawyer knew as much of the cave as any one. - -The procession moved along the main avenue some three-quarters of a -mile, and then groups and couples began to slip aside into branch -avenues, fly along the dismal corridors, and take each other by -surprise at points where the corridors joined again. Parties were able -to elude each other for the space of half an hour without going beyond -the "known" ground. - -By-and-by, one group after another came straggling back to the mouth -of the cave, panting, hilarious, smeared from head to foot with tallow -drippings, daubed with clay, and entirely delighted with the success of -the day. Then they were astonished to find that they had been taking no -note of time and that night was about at hand. The clanging bell had -been calling for half an hour. However, this sort of close to the day's -adventures was romantic and therefore satisfactory. When the ferryboat -with her wild freight pushed into the stream, nobody cared sixpence for -the wasted time but the captain of the craft. - -Huck was already upon his watch when the ferryboat's lights went -glinting past the wharf. He heard no noise on board, for the young -people were as subdued and still as people usually are who are nearly -tired to death. He wondered what boat it was, and why she did not stop -at the wharf--and then he dropped her out of his mind and put his -attention upon his business. The night was growing cloudy and dark. Ten -o'clock came, and the noise of vehicles ceased, scattered lights began -to wink out, all straggling foot-passengers disappeared, the village -betook itself to its slumbers and left the small watcher alone with the -silence and the ghosts. Eleven o'clock came, and the tavern lights were -put out; darkness everywhere, now. Huck waited what seemed a weary long -time, but nothing happened. His faith was weakening. Was there any use? -Was there really any use? Why not give it up and turn in? - -A noise fell upon his ear. He was all attention in an instant. The -alley door closed softly. He sprang to the corner of the brick store. -The next moment two men brushed by him, and one seemed to have -something under his arm. It must be that box! So they were going to -remove the treasure. Why call Tom now? It would be absurd--the men -would get away with the box and never be found again. No, he would -stick to their wake and follow them; he would trust to the darkness for -security from discovery. So communing with himself, Huck stepped out -and glided along behind the men, cat-like, with bare feet, allowing -them to keep just far enough ahead not to be invisible. - -They moved up the river street three blocks, then turned to the left -up a cross-street. They went straight ahead, then, until they came to -the path that led up Cardiff Hill; this they took. They passed by the -old Welshman's house, half-way up the hill, without hesitating, and -still climbed upward. Good, thought Huck, they will bury it in the old -quarry. But they never stopped at the quarry. They passed on, up the -summit. They plunged into the narrow path between the tall sumach -bushes, and were at once hidden in the gloom. Huck closed up and -shortened his distance, now, for they would never be able to see him. -He trotted along awhile; then slackened his pace, fearing he was -gaining too fast; moved on a piece, then stopped altogether; listened; -no sound; none, save that he seemed to hear the beating of his own -heart. The hooting of an owl came over the hill--ominous sound! But no -footsteps. Heavens, was everything lost! He was about to spring with -winged feet, when a man cleared his throat not four feet from him! -Huck's heart shot into his throat, but he swallowed it again; and then -he stood there shaking as if a dozen agues had taken charge of him at -once, and so weak that he thought he must surely fall to the ground. He -knew where he was. He knew he was within five steps of the stile -leading into Widow Douglas' grounds. Very well, he thought, let them -bury it there; it won't be hard to find. - -Now there was a voice--a very low voice--Injun Joe's: - -"Damn her, maybe she's got company--there's lights, late as it is." - -"I can't see any." - -This was that stranger's voice--the stranger of the haunted house. A -deadly chill went to Huck's heart--this, then, was the "revenge" job! -His thought was, to fly. Then he remembered that the Widow Douglas had -been kind to him more than once, and maybe these men were going to -murder her. He wished he dared venture to warn her; but he knew he -didn't dare--they might come and catch him. He thought all this and -more in the moment that elapsed between the stranger's remark and Injun -Joe's next--which was-- - -"Because the bush is in your way. Now--this way--now you see, don't -you?" - -"Yes. Well, there IS company there, I reckon. Better give it up." - -"Give it up, and I just leaving this country forever! Give it up and -maybe never have another chance. I tell you again, as I've told you -before, I don't care for her swag--you may have it. But her husband was -rough on me--many times he was rough on me--and mainly he was the -justice of the peace that jugged me for a vagrant. And that ain't all. -It ain't a millionth part of it! He had me HORSEWHIPPED!--horsewhipped -in front of the jail, like a nigger!--with all the town looking on! -HORSEWHIPPED!--do you understand? He took advantage of me and died. But -I'll take it out of HER." - -"Oh, don't kill her! Don't do that!" - -"Kill? Who said anything about killing? I would kill HIM if he was -here; but not her. When you want to get revenge on a woman you don't -kill her--bosh! you go for her looks. You slit her nostrils--you notch -her ears like a sow!" - -"By God, that's--" - -"Keep your opinion to yourself! It will be safest for you. I'll tie -her to the bed. If she bleeds to death, is that my fault? I'll not cry, -if she does. My friend, you'll help me in this thing--for MY sake ---that's why you're here--I mightn't be able alone. If you flinch, I'll -kill you. Do you understand that? And if I have to kill you, I'll kill -her--and then I reckon nobody'll ever know much about who done this -business." - -"Well, if it's got to be done, let's get at it. The quicker the -better--I'm all in a shiver." - -"Do it NOW? And company there? Look here--I'll get suspicious of you, -first thing you know. No--we'll wait till the lights are out--there's -no hurry." - -Huck felt that a silence was going to ensue--a thing still more awful -than any amount of murderous talk; so he held his breath and stepped -gingerly back; planted his foot carefully and firmly, after balancing, -one-legged, in a precarious way and almost toppling over, first on one -side and then on the other. He took another step back, with the same -elaboration and the same risks; then another and another, and--a twig -snapped under his foot! His breath stopped and he listened. There was -no sound--the stillness was perfect. His gratitude was measureless. Now -he turned in his tracks, between the walls of sumach bushes--turned -himself as carefully as if he were a ship--and then stepped quickly but -cautiously along. When he emerged at the quarry he felt secure, and so -he picked up his nimble heels and flew. Down, down he sped, till he -reached the Welshman's. He banged at the door, and presently the heads -of the old man and his two stalwart sons were thrust from windows. - -"What's the row there? Who's banging? What do you want?" - -"Let me in--quick! I'll tell everything." - -"Why, who are you?" - -"Huckleberry Finn--quick, let me in!" - -"Huckleberry Finn, indeed! It ain't a name to open many doors, I -judge! But let him in, lads, and let's see what's the trouble." - -"Please don't ever tell I told you," were Huck's first words when he -got in. "Please don't--I'd be killed, sure--but the widow's been good -friends to me sometimes, and I want to tell--I WILL tell if you'll -promise you won't ever say it was me." - -"By George, he HAS got something to tell, or he wouldn't act so!" -exclaimed the old man; "out with it and nobody here'll ever tell, lad." - -Three minutes later the old man and his sons, well armed, were up the -hill, and just entering the sumach path on tiptoe, their weapons in -their hands. Huck accompanied them no further. He hid behind a great -bowlder and fell to listening. There was a lagging, anxious silence, -and then all of a sudden there was an explosion of firearms and a cry. - -Huck waited for no particulars. He sprang away and sped down the hill -as fast as his legs could carry him. - - - -CHAPTER XXX - -AS the earliest suspicion of dawn appeared on Sunday morning, Huck -came groping up the hill and rapped gently at the old Welshman's door. -The inmates were asleep, but it was a sleep that was set on a -hair-trigger, on account of the exciting episode of the night. A call -came from a window: - -"Who's there!" - -Huck's scared voice answered in a low tone: - -"Please let me in! It's only Huck Finn!" - -"It's a name that can open this door night or day, lad!--and welcome!" - -These were strange words to the vagabond boy's ears, and the -pleasantest he had ever heard. He could not recollect that the closing -word had ever been applied in his case before. The door was quickly -unlocked, and he entered. Huck was given a seat and the old man and his -brace of tall sons speedily dressed themselves. - -"Now, my boy, I hope you're good and hungry, because breakfast will be -ready as soon as the sun's up, and we'll have a piping hot one, too ---make yourself easy about that! I and the boys hoped you'd turn up and -stop here last night." - -"I was awful scared," said Huck, "and I run. I took out when the -pistols went off, and I didn't stop for three mile. I've come now becuz -I wanted to know about it, you know; and I come before daylight becuz I -didn't want to run across them devils, even if they was dead." - -"Well, poor chap, you do look as if you'd had a hard night of it--but -there's a bed here for you when you've had your breakfast. No, they -ain't dead, lad--we are sorry enough for that. You see we knew right -where to put our hands on them, by your description; so we crept along -on tiptoe till we got within fifteen feet of them--dark as a cellar -that sumach path was--and just then I found I was going to sneeze. It -was the meanest kind of luck! I tried to keep it back, but no use ---'twas bound to come, and it did come! I was in the lead with my pistol -raised, and when the sneeze started those scoundrels a-rustling to get -out of the path, I sung out, 'Fire boys!' and blazed away at the place -where the rustling was. So did the boys. But they were off in a jiffy, -those villains, and we after them, down through the woods. I judge we -never touched them. They fired a shot apiece as they started, but their -bullets whizzed by and didn't do us any harm. As soon as we lost the -sound of their feet we quit chasing, and went down and stirred up the -constables. They got a posse together, and went off to guard the river -bank, and as soon as it is light the sheriff and a gang are going to -beat up the woods. My boys will be with them presently. I wish we had -some sort of description of those rascals--'twould help a good deal. -But you couldn't see what they were like, in the dark, lad, I suppose?" - -"Oh yes; I saw them down-town and follered them." - -"Splendid! Describe them--describe them, my boy!" - -"One's the old deaf and dumb Spaniard that's ben around here once or -twice, and t'other's a mean-looking, ragged--" - -"That's enough, lad, we know the men! Happened on them in the woods -back of the widow's one day, and they slunk away. Off with you, boys, -and tell the sheriff--get your breakfast to-morrow morning!" - -The Welshman's sons departed at once. As they were leaving the room -Huck sprang up and exclaimed: - -"Oh, please don't tell ANYbody it was me that blowed on them! Oh, -please!" - -"All right if you say it, Huck, but you ought to have the credit of -what you did." - -"Oh no, no! Please don't tell!" - -When the young men were gone, the old Welshman said: - -"They won't tell--and I won't. But why don't you want it known?" - -Huck would not explain, further than to say that he already knew too -much about one of those men and would not have the man know that he -knew anything against him for the whole world--he would be killed for -knowing it, sure. - -The old man promised secrecy once more, and said: - -"How did you come to follow these fellows, lad? Were they looking -suspicious?" - -Huck was silent while he framed a duly cautious reply. Then he said: - -"Well, you see, I'm a kind of a hard lot,--least everybody says so, -and I don't see nothing agin it--and sometimes I can't sleep much, on -account of thinking about it and sort of trying to strike out a new way -of doing. That was the way of it last night. I couldn't sleep, and so I -come along up-street 'bout midnight, a-turning it all over, and when I -got to that old shackly brick store by the Temperance Tavern, I backed -up agin the wall to have another think. Well, just then along comes -these two chaps slipping along close by me, with something under their -arm, and I reckoned they'd stole it. One was a-smoking, and t'other one -wanted a light; so they stopped right before me and the cigars lit up -their faces and I see that the big one was the deaf and dumb Spaniard, -by his white whiskers and the patch on his eye, and t'other one was a -rusty, ragged-looking devil." - -"Could you see the rags by the light of the cigars?" - -This staggered Huck for a moment. Then he said: - -"Well, I don't know--but somehow it seems as if I did." - -"Then they went on, and you--" - -"Follered 'em--yes. That was it. I wanted to see what was up--they -sneaked along so. I dogged 'em to the widder's stile, and stood in the -dark and heard the ragged one beg for the widder, and the Spaniard -swear he'd spile her looks just as I told you and your two--" - -"What! The DEAF AND DUMB man said all that!" - -Huck had made another terrible mistake! He was trying his best to keep -the old man from getting the faintest hint of who the Spaniard might -be, and yet his tongue seemed determined to get him into trouble in -spite of all he could do. He made several efforts to creep out of his -scrape, but the old man's eye was upon him and he made blunder after -blunder. Presently the Welshman said: - -"My boy, don't be afraid of me. I wouldn't hurt a hair of your head -for all the world. No--I'd protect you--I'd protect you. This Spaniard -is not deaf and dumb; you've let that slip without intending it; you -can't cover that up now. You know something about that Spaniard that -you want to keep dark. Now trust me--tell me what it is, and trust me ---I won't betray you." - -Huck looked into the old man's honest eyes a moment, then bent over -and whispered in his ear: - -"'Tain't a Spaniard--it's Injun Joe!" - -The Welshman almost jumped out of his chair. In a moment he said: - -"It's all plain enough, now. When you talked about notching ears and -slitting noses I judged that that was your own embellishment, because -white men don't take that sort of revenge. But an Injun! That's a -different matter altogether." - -During breakfast the talk went on, and in the course of it the old man -said that the last thing which he and his sons had done, before going -to bed, was to get a lantern and examine the stile and its vicinity for -marks of blood. They found none, but captured a bulky bundle of-- - -"Of WHAT?" - -If the words had been lightning they could not have leaped with a more -stunning suddenness from Huck's blanched lips. His eyes were staring -wide, now, and his breath suspended--waiting for the answer. The -Welshman started--stared in return--three seconds--five seconds--ten ---then replied: - -"Of burglar's tools. Why, what's the MATTER with you?" - -Huck sank back, panting gently, but deeply, unutterably grateful. The -Welshman eyed him gravely, curiously--and presently said: - -"Yes, burglar's tools. That appears to relieve you a good deal. But -what did give you that turn? What were YOU expecting we'd found?" - -Huck was in a close place--the inquiring eye was upon him--he would -have given anything for material for a plausible answer--nothing -suggested itself--the inquiring eye was boring deeper and deeper--a -senseless reply offered--there was no time to weigh it, so at a venture -he uttered it--feebly: - -"Sunday-school books, maybe." - -Poor Huck was too distressed to smile, but the old man laughed loud -and joyously, shook up the details of his anatomy from head to foot, -and ended by saying that such a laugh was money in a-man's pocket, -because it cut down the doctor's bill like everything. Then he added: - -"Poor old chap, you're white and jaded--you ain't well a bit--no -wonder you're a little flighty and off your balance. But you'll come -out of it. Rest and sleep will fetch you out all right, I hope." - -Huck was irritated to think he had been such a goose and betrayed such -a suspicious excitement, for he had dropped the idea that the parcel -brought from the tavern was the treasure, as soon as he had heard the -talk at the widow's stile. He had only thought it was not the treasure, -however--he had not known that it wasn't--and so the suggestion of a -captured bundle was too much for his self-possession. But on the whole -he felt glad the little episode had happened, for now he knew beyond -all question that that bundle was not THE bundle, and so his mind was -at rest and exceedingly comfortable. In fact, everything seemed to be -drifting just in the right direction, now; the treasure must be still -in No. 2, the men would be captured and jailed that day, and he and Tom -could seize the gold that night without any trouble or any fear of -interruption. - -Just as breakfast was completed there was a knock at the door. Huck -jumped for a hiding-place, for he had no mind to be connected even -remotely with the late event. The Welshman admitted several ladies and -gentlemen, among them the Widow Douglas, and noticed that groups of -citizens were climbing up the hill--to stare at the stile. So the news -had spread. The Welshman had to tell the story of the night to the -visitors. The widow's gratitude for her preservation was outspoken. - -"Don't say a word about it, madam. There's another that you're more -beholden to than you are to me and my boys, maybe, but he don't allow -me to tell his name. We wouldn't have been there but for him." - -Of course this excited a curiosity so vast that it almost belittled -the main matter--but the Welshman allowed it to eat into the vitals of -his visitors, and through them be transmitted to the whole town, for he -refused to part with his secret. When all else had been learned, the -widow said: - -"I went to sleep reading in bed and slept straight through all that -noise. Why didn't you come and wake me?" - -"We judged it warn't worth while. Those fellows warn't likely to come -again--they hadn't any tools left to work with, and what was the use of -waking you up and scaring you to death? My three negro men stood guard -at your house all the rest of the night. They've just come back." - -More visitors came, and the story had to be told and retold for a -couple of hours more. - -There was no Sabbath-school during day-school vacation, but everybody -was early at church. The stirring event was well canvassed. News came -that not a sign of the two villains had been yet discovered. When the -sermon was finished, Judge Thatcher's wife dropped alongside of Mrs. -Harper as she moved down the aisle with the crowd and said: - -"Is my Becky going to sleep all day? I just expected she would be -tired to death." - -"Your Becky?" - -"Yes," with a startled look--"didn't she stay with you last night?" - -"Why, no." - -Mrs. Thatcher turned pale, and sank into a pew, just as Aunt Polly, -talking briskly with a friend, passed by. Aunt Polly said: - -"Good-morning, Mrs. Thatcher. Good-morning, Mrs. Harper. I've got a -boy that's turned up missing. I reckon my Tom stayed at your house last -night--one of you. And now he's afraid to come to church. I've got to -settle with him." - -Mrs. Thatcher shook her head feebly and turned paler than ever. - -"He didn't stay with us," said Mrs. Harper, beginning to look uneasy. -A marked anxiety came into Aunt Polly's face. - -"Joe Harper, have you seen my Tom this morning?" - -"No'm." - -"When did you see him last?" - -Joe tried to remember, but was not sure he could say. The people had -stopped moving out of church. Whispers passed along, and a boding -uneasiness took possession of every countenance. Children were -anxiously questioned, and young teachers. They all said they had not -noticed whether Tom and Becky were on board the ferryboat on the -homeward trip; it was dark; no one thought of inquiring if any one was -missing. One young man finally blurted out his fear that they were -still in the cave! Mrs. Thatcher swooned away. Aunt Polly fell to -crying and wringing her hands. - -The alarm swept from lip to lip, from group to group, from street to -street, and within five minutes the bells were wildly clanging and the -whole town was up! The Cardiff Hill episode sank into instant -insignificance, the burglars were forgotten, horses were saddled, -skiffs were manned, the ferryboat ordered out, and before the horror -was half an hour old, two hundred men were pouring down highroad and -river toward the cave. - -All the long afternoon the village seemed empty and dead. Many women -visited Aunt Polly and Mrs. Thatcher and tried to comfort them. They -cried with them, too, and that was still better than words. All the -tedious night the town waited for news; but when the morning dawned at -last, all the word that came was, "Send more candles--and send food." -Mrs. Thatcher was almost crazed; and Aunt Polly, also. Judge Thatcher -sent messages of hope and encouragement from the cave, but they -conveyed no real cheer. - -The old Welshman came home toward daylight, spattered with -candle-grease, smeared with clay, and almost worn out. He found Huck -still in the bed that had been provided for him, and delirious with -fever. The physicians were all at the cave, so the Widow Douglas came -and took charge of the patient. She said she would do her best by him, -because, whether he was good, bad, or indifferent, he was the Lord's, -and nothing that was the Lord's was a thing to be neglected. The -Welshman said Huck had good spots in him, and the widow said: - -"You can depend on it. That's the Lord's mark. He don't leave it off. -He never does. Puts it somewhere on every creature that comes from his -hands." - -Early in the forenoon parties of jaded men began to straggle into the -village, but the strongest of the citizens continued searching. All the -news that could be gained was that remotenesses of the cavern were -being ransacked that had never been visited before; that every corner -and crevice was going to be thoroughly searched; that wherever one -wandered through the maze of passages, lights were to be seen flitting -hither and thither in the distance, and shoutings and pistol-shots sent -their hollow reverberations to the ear down the sombre aisles. In one -place, far from the section usually traversed by tourists, the names -"BECKY & TOM" had been found traced upon the rocky wall with -candle-smoke, and near at hand a grease-soiled bit of ribbon. Mrs. -Thatcher recognized the ribbon and cried over it. She said it was the -last relic she should ever have of her child; and that no other memorial -of her could ever be so precious, because this one parted latest from -the living body before the awful death came. Some said that now and -then, in the cave, a far-away speck of light would glimmer, and then a -glorious shout would burst forth and a score of men go trooping down the -echoing aisle--and then a sickening disappointment always followed; the -children were not there; it was only a searcher's light. - -Three dreadful days and nights dragged their tedious hours along, and -the village sank into a hopeless stupor. No one had heart for anything. -The accidental discovery, just made, that the proprietor of the -Temperance Tavern kept liquor on his premises, scarcely fluttered the -public pulse, tremendous as the fact was. In a lucid interval, Huck -feebly led up to the subject of taverns, and finally asked--dimly -dreading the worst--if anything had been discovered at the Temperance -Tavern since he had been ill. - -"Yes," said the widow. - -Huck started up in bed, wild-eyed: - -"What? What was it?" - -"Liquor!--and the place has been shut up. Lie down, child--what a turn -you did give me!" - -"Only tell me just one thing--only just one--please! Was it Tom Sawyer -that found it?" - -The widow burst into tears. "Hush, hush, child, hush! I've told you -before, you must NOT talk. You are very, very sick!" - -Then nothing but liquor had been found; there would have been a great -powwow if it had been the gold. So the treasure was gone forever--gone -forever! But what could she be crying about? Curious that she should -cry. - -These thoughts worked their dim way through Huck's mind, and under the -weariness they gave him he fell asleep. The widow said to herself: - -"There--he's asleep, poor wreck. Tom Sawyer find it! Pity but somebody -could find Tom Sawyer! Ah, there ain't many left, now, that's got hope -enough, or strength enough, either, to go on searching." - - - -CHAPTER XXXI - -NOW to return to Tom and Becky's share in the picnic. They tripped -along the murky aisles with the rest of the company, visiting the -familiar wonders of the cave--wonders dubbed with rather -over-descriptive names, such as "The Drawing-Room," "The Cathedral," -"Aladdin's Palace," and so on. Presently the hide-and-seek frolicking -began, and Tom and Becky engaged in it with zeal until the exertion -began to grow a trifle wearisome; then they wandered down a sinuous -avenue holding their candles aloft and reading the tangled web-work of -names, dates, post-office addresses, and mottoes with which the rocky -walls had been frescoed (in candle-smoke). Still drifting along and -talking, they scarcely noticed that they were now in a part of the cave -whose walls were not frescoed. They smoked their own names under an -overhanging shelf and moved on. Presently they came to a place where a -little stream of water, trickling over a ledge and carrying a limestone -sediment with it, had, in the slow-dragging ages, formed a laced and -ruffled Niagara in gleaming and imperishable stone. Tom squeezed his -small body behind it in order to illuminate it for Becky's -gratification. He found that it curtained a sort of steep natural -stairway which was enclosed between narrow walls, and at once the -ambition to be a discoverer seized him. Becky responded to his call, -and they made a smoke-mark for future guidance, and started upon their -quest. They wound this way and that, far down into the secret depths of -the cave, made another mark, and branched off in search of novelties to -tell the upper world about. In one place they found a spacious cavern, -from whose ceiling depended a multitude of shining stalactites of the -length and circumference of a man's leg; they walked all about it, -wondering and admiring, and presently left it by one of the numerous -passages that opened into it. This shortly brought them to a bewitching -spring, whose basin was incrusted with a frostwork of glittering -crystals; it was in the midst of a cavern whose walls were supported by -many fantastic pillars which had been formed by the joining of great -stalactites and stalagmites together, the result of the ceaseless -water-drip of centuries. Under the roof vast knots of bats had packed -themselves together, thousands in a bunch; the lights disturbed the -creatures and they came flocking down by hundreds, squeaking and -darting furiously at the candles. Tom knew their ways and the danger of -this sort of conduct. He seized Becky's hand and hurried her into the -first corridor that offered; and none too soon, for a bat struck -Becky's light out with its wing while she was passing out of the -cavern. The bats chased the children a good distance; but the fugitives -plunged into every new passage that offered, and at last got rid of the -perilous things. Tom found a subterranean lake, shortly, which -stretched its dim length away until its shape was lost in the shadows. -He wanted to explore its borders, but concluded that it would be best -to sit down and rest awhile, first. Now, for the first time, the deep -stillness of the place laid a clammy hand upon the spirits of the -children. Becky said: - -"Why, I didn't notice, but it seems ever so long since I heard any of -the others." - -"Come to think, Becky, we are away down below them--and I don't know -how far away north, or south, or east, or whichever it is. We couldn't -hear them here." - -Becky grew apprehensive. - -"I wonder how long we've been down here, Tom? We better start back." - -"Yes, I reckon we better. P'raps we better." - -"Can you find the way, Tom? It's all a mixed-up crookedness to me." - -"I reckon I could find it--but then the bats. If they put our candles -out it will be an awful fix. Let's try some other way, so as not to go -through there." - -"Well. But I hope we won't get lost. It would be so awful!" and the -girl shuddered at the thought of the dreadful possibilities. - -They started through a corridor, and traversed it in silence a long -way, glancing at each new opening, to see if there was anything -familiar about the look of it; but they were all strange. Every time -Tom made an examination, Becky would watch his face for an encouraging -sign, and he would say cheerily: - -"Oh, it's all right. This ain't the one, but we'll come to it right -away!" - -But he felt less and less hopeful with each failure, and presently -began to turn off into diverging avenues at sheer random, in desperate -hope of finding the one that was wanted. He still said it was "all -right," but there was such a leaden dread at his heart that the words -had lost their ring and sounded just as if he had said, "All is lost!" -Becky clung to his side in an anguish of fear, and tried hard to keep -back the tears, but they would come. At last she said: - -"Oh, Tom, never mind the bats, let's go back that way! We seem to get -worse and worse off all the time." - -"Listen!" said he. - -Profound silence; silence so deep that even their breathings were -conspicuous in the hush. Tom shouted. The call went echoing down the -empty aisles and died out in the distance in a faint sound that -resembled a ripple of mocking laughter. - -"Oh, don't do it again, Tom, it is too horrid," said Becky. - -"It is horrid, but I better, Becky; they might hear us, you know," and -he shouted again. - -The "might" was even a chillier horror than the ghostly laughter, it -so confessed a perishing hope. The children stood still and listened; -but there was no result. Tom turned upon the back track at once, and -hurried his steps. It was but a little while before a certain -indecision in his manner revealed another fearful fact to Becky--he -could not find his way back! - -"Oh, Tom, you didn't make any marks!" - -"Becky, I was such a fool! Such a fool! I never thought we might want -to come back! No--I can't find the way. It's all mixed up." - -"Tom, Tom, we're lost! we're lost! We never can get out of this awful -place! Oh, why DID we ever leave the others!" - -She sank to the ground and burst into such a frenzy of crying that Tom -was appalled with the idea that she might die, or lose her reason. He -sat down by her and put his arms around her; she buried her face in his -bosom, she clung to him, she poured out her terrors, her unavailing -regrets, and the far echoes turned them all to jeering laughter. Tom -begged her to pluck up hope again, and she said she could not. He fell -to blaming and abusing himself for getting her into this miserable -situation; this had a better effect. She said she would try to hope -again, she would get up and follow wherever he might lead if only he -would not talk like that any more. For he was no more to blame than -she, she said. - -So they moved on again--aimlessly--simply at random--all they could do -was to move, keep moving. For a little while, hope made a show of -reviving--not with any reason to back it, but only because it is its -nature to revive when the spring has not been taken out of it by age -and familiarity with failure. - -By-and-by Tom took Becky's candle and blew it out. This economy meant -so much! Words were not needed. Becky understood, and her hope died -again. She knew that Tom had a whole candle and three or four pieces in -his pockets--yet he must economize. - -By-and-by, fatigue began to assert its claims; the children tried to -pay attention, for it was dreadful to think of sitting down when time -was grown to be so precious, moving, in some direction, in any -direction, was at least progress and might bear fruit; but to sit down -was to invite death and shorten its pursuit. - -At last Becky's frail limbs refused to carry her farther. She sat -down. Tom rested with her, and they talked of home, and the friends -there, and the comfortable beds and, above all, the light! Becky cried, -and Tom tried to think of some way of comforting her, but all his -encouragements were grown threadbare with use, and sounded like -sarcasms. Fatigue bore so heavily upon Becky that she drowsed off to -sleep. Tom was grateful. He sat looking into her drawn face and saw it -grow smooth and natural under the influence of pleasant dreams; and -by-and-by a smile dawned and rested there. The peaceful face reflected -somewhat of peace and healing into his own spirit, and his thoughts -wandered away to bygone times and dreamy memories. While he was deep in -his musings, Becky woke up with a breezy little laugh--but it was -stricken dead upon her lips, and a groan followed it. - -"Oh, how COULD I sleep! I wish I never, never had waked! No! No, I -don't, Tom! Don't look so! I won't say it again." - -"I'm glad you've slept, Becky; you'll feel rested, now, and we'll find -the way out." - -"We can try, Tom; but I've seen such a beautiful country in my dream. -I reckon we are going there." - -"Maybe not, maybe not. Cheer up, Becky, and let's go on trying." - -They rose up and wandered along, hand in hand and hopeless. They tried -to estimate how long they had been in the cave, but all they knew was -that it seemed days and weeks, and yet it was plain that this could not -be, for their candles were not gone yet. A long time after this--they -could not tell how long--Tom said they must go softly and listen for -dripping water--they must find a spring. They found one presently, and -Tom said it was time to rest again. Both were cruelly tired, yet Becky -said she thought she could go a little farther. She was surprised to -hear Tom dissent. She could not understand it. They sat down, and Tom -fastened his candle to the wall in front of them with some clay. -Thought was soon busy; nothing was said for some time. Then Becky broke -the silence: - -"Tom, I am so hungry!" - -Tom took something out of his pocket. - -"Do you remember this?" said he. - -Becky almost smiled. - -"It's our wedding-cake, Tom." - -"Yes--I wish it was as big as a barrel, for it's all we've got." - -"I saved it from the picnic for us to dream on, Tom, the way grown-up -people do with wedding-cake--but it'll be our--" - -She dropped the sentence where it was. Tom divided the cake and Becky -ate with good appetite, while Tom nibbled at his moiety. There was -abundance of cold water to finish the feast with. By-and-by Becky -suggested that they move on again. Tom was silent a moment. Then he -said: - -"Becky, can you bear it if I tell you something?" - -Becky's face paled, but she thought she could. - -"Well, then, Becky, we must stay here, where there's water to drink. -That little piece is our last candle!" - -Becky gave loose to tears and wailings. Tom did what he could to -comfort her, but with little effect. At length Becky said: - -"Tom!" - -"Well, Becky?" - -"They'll miss us and hunt for us!" - -"Yes, they will! Certainly they will!" - -"Maybe they're hunting for us now, Tom." - -"Why, I reckon maybe they are. I hope they are." - -"When would they miss us, Tom?" - -"When they get back to the boat, I reckon." - -"Tom, it might be dark then--would they notice we hadn't come?" - -"I don't know. But anyway, your mother would miss you as soon as they -got home." - -A frightened look in Becky's face brought Tom to his senses and he saw -that he had made a blunder. Becky was not to have gone home that night! -The children became silent and thoughtful. In a moment a new burst of -grief from Becky showed Tom that the thing in his mind had struck hers -also--that the Sabbath morning might be half spent before Mrs. Thatcher -discovered that Becky was not at Mrs. Harper's. - -The children fastened their eyes upon their bit of candle and watched -it melt slowly and pitilessly away; saw the half inch of wick stand -alone at last; saw the feeble flame rise and fall, climb the thin -column of smoke, linger at its top a moment, and then--the horror of -utter darkness reigned! - -How long afterward it was that Becky came to a slow consciousness that -she was crying in Tom's arms, neither could tell. All that they knew -was, that after what seemed a mighty stretch of time, both awoke out of -a dead stupor of sleep and resumed their miseries once more. Tom said -it might be Sunday, now--maybe Monday. He tried to get Becky to talk, -but her sorrows were too oppressive, all her hopes were gone. Tom said -that they must have been missed long ago, and no doubt the search was -going on. He would shout and maybe some one would come. He tried it; -but in the darkness the distant echoes sounded so hideously that he -tried it no more. - -The hours wasted away, and hunger came to torment the captives again. -A portion of Tom's half of the cake was left; they divided and ate it. -But they seemed hungrier than before. The poor morsel of food only -whetted desire. - -By-and-by Tom said: - -"SH! Did you hear that?" - -Both held their breath and listened. There was a sound like the -faintest, far-off shout. Instantly Tom answered it, and leading Becky -by the hand, started groping down the corridor in its direction. -Presently he listened again; again the sound was heard, and apparently -a little nearer. - -"It's them!" said Tom; "they're coming! Come along, Becky--we're all -right now!" - -The joy of the prisoners was almost overwhelming. Their speed was -slow, however, because pitfalls were somewhat common, and had to be -guarded against. They shortly came to one and had to stop. It might be -three feet deep, it might be a hundred--there was no passing it at any -rate. Tom got down on his breast and reached as far down as he could. -No bottom. They must stay there and wait until the searchers came. They -listened; evidently the distant shoutings were growing more distant! a -moment or two more and they had gone altogether. The heart-sinking -misery of it! Tom whooped until he was hoarse, but it was of no use. He -talked hopefully to Becky; but an age of anxious waiting passed and no -sounds came again. - -The children groped their way back to the spring. The weary time -dragged on; they slept again, and awoke famished and woe-stricken. Tom -believed it must be Tuesday by this time. - -Now an idea struck him. There were some side passages near at hand. It -would be better to explore some of these than bear the weight of the -heavy time in idleness. He took a kite-line from his pocket, tied it to -a projection, and he and Becky started, Tom in the lead, unwinding the -line as he groped along. At the end of twenty steps the corridor ended -in a "jumping-off place." Tom got down on his knees and felt below, and -then as far around the corner as he could reach with his hands -conveniently; he made an effort to stretch yet a little farther to the -right, and at that moment, not twenty yards away, a human hand, holding -a candle, appeared from behind a rock! Tom lifted up a glorious shout, -and instantly that hand was followed by the body it belonged to--Injun -Joe's! Tom was paralyzed; he could not move. He was vastly gratified -the next moment, to see the "Spaniard" take to his heels and get -himself out of sight. Tom wondered that Joe had not recognized his -voice and come over and killed him for testifying in court. But the -echoes must have disguised the voice. Without doubt, that was it, he -reasoned. Tom's fright weakened every muscle in his body. He said to -himself that if he had strength enough to get back to the spring he -would stay there, and nothing should tempt him to run the risk of -meeting Injun Joe again. He was careful to keep from Becky what it was -he had seen. He told her he had only shouted "for luck." - -But hunger and wretchedness rise superior to fears in the long run. -Another tedious wait at the spring and another long sleep brought -changes. The children awoke tortured with a raging hunger. Tom believed -that it must be Wednesday or Thursday or even Friday or Saturday, now, -and that the search had been given over. He proposed to explore another -passage. He felt willing to risk Injun Joe and all other terrors. But -Becky was very weak. She had sunk into a dreary apathy and would not be -roused. She said she would wait, now, where she was, and die--it would -not be long. She told Tom to go with the kite-line and explore if he -chose; but she implored him to come back every little while and speak -to her; and she made him promise that when the awful time came, he -would stay by her and hold her hand until all was over. - -Tom kissed her, with a choking sensation in his throat, and made a -show of being confident of finding the searchers or an escape from the -cave; then he took the kite-line in his hand and went groping down one -of the passages on his hands and knees, distressed with hunger and sick -with bodings of coming doom. - - - -CHAPTER XXXII - -TUESDAY afternoon came, and waned to the twilight. The village of St. -Petersburg still mourned. The lost children had not been found. Public -prayers had been offered up for them, and many and many a private -prayer that had the petitioner's whole heart in it; but still no good -news came from the cave. The majority of the searchers had given up the -quest and gone back to their daily avocations, saying that it was plain -the children could never be found. Mrs. Thatcher was very ill, and a -great part of the time delirious. People said it was heartbreaking to -hear her call her child, and raise her head and listen a whole minute -at a time, then lay it wearily down again with a moan. Aunt Polly had -drooped into a settled melancholy, and her gray hair had grown almost -white. The village went to its rest on Tuesday night, sad and forlorn. - -Away in the middle of the night a wild peal burst from the village -bells, and in a moment the streets were swarming with frantic half-clad -people, who shouted, "Turn out! turn out! they're found! they're -found!" Tin pans and horns were added to the din, the population massed -itself and moved toward the river, met the children coming in an open -carriage drawn by shouting citizens, thronged around it, joined its -homeward march, and swept magnificently up the main street roaring -huzzah after huzzah! - -The village was illuminated; nobody went to bed again; it was the -greatest night the little town had ever seen. During the first half-hour -a procession of villagers filed through Judge Thatcher's house, seized -the saved ones and kissed them, squeezed Mrs. Thatcher's hand, tried to -speak but couldn't--and drifted out raining tears all over the place. - -Aunt Polly's happiness was complete, and Mrs. Thatcher's nearly so. It -would be complete, however, as soon as the messenger dispatched with -the great news to the cave should get the word to her husband. Tom lay -upon a sofa with an eager auditory about him and told the history of -the wonderful adventure, putting in many striking additions to adorn it -withal; and closed with a description of how he left Becky and went on -an exploring expedition; how he followed two avenues as far as his -kite-line would reach; how he followed a third to the fullest stretch of -the kite-line, and was about to turn back when he glimpsed a far-off -speck that looked like daylight; dropped the line and groped toward it, -pushed his head and shoulders through a small hole, and saw the broad -Mississippi rolling by! And if it had only happened to be night he would -not have seen that speck of daylight and would not have explored that -passage any more! He told how he went back for Becky and broke the good -news and she told him not to fret her with such stuff, for she was -tired, and knew she was going to die, and wanted to. He described how he -labored with her and convinced her; and how she almost died for joy when -she had groped to where she actually saw the blue speck of daylight; how -he pushed his way out at the hole and then helped her out; how they sat -there and cried for gladness; how some men came along in a skiff and Tom -hailed them and told them their situation and their famished condition; -how the men didn't believe the wild tale at first, "because," said they, -"you are five miles down the river below the valley the cave is in" ---then took them aboard, rowed to a house, gave them supper, made them -rest till two or three hours after dark and then brought them home. - -Before day-dawn, Judge Thatcher and the handful of searchers with him -were tracked out, in the cave, by the twine clews they had strung -behind them, and informed of the great news. - -Three days and nights of toil and hunger in the cave were not to be -shaken off at once, as Tom and Becky soon discovered. They were -bedridden all of Wednesday and Thursday, and seemed to grow more and -more tired and worn, all the time. Tom got about, a little, on -Thursday, was down-town Friday, and nearly as whole as ever Saturday; -but Becky did not leave her room until Sunday, and then she looked as -if she had passed through a wasting illness. - -Tom learned of Huck's sickness and went to see him on Friday, but -could not be admitted to the bedroom; neither could he on Saturday or -Sunday. He was admitted daily after that, but was warned to keep still -about his adventure and introduce no exciting topic. The Widow Douglas -stayed by to see that he obeyed. At home Tom learned of the Cardiff -Hill event; also that the "ragged man's" body had eventually been found -in the river near the ferry-landing; he had been drowned while trying -to escape, perhaps. - -About a fortnight after Tom's rescue from the cave, he started off to -visit Huck, who had grown plenty strong enough, now, to hear exciting -talk, and Tom had some that would interest him, he thought. Judge -Thatcher's house was on Tom's way, and he stopped to see Becky. The -Judge and some friends set Tom to talking, and some one asked him -ironically if he wouldn't like to go to the cave again. Tom said he -thought he wouldn't mind it. The Judge said: - -"Well, there are others just like you, Tom, I've not the least doubt. -But we have taken care of that. Nobody will get lost in that cave any -more." - -"Why?" - -"Because I had its big door sheathed with boiler iron two weeks ago, -and triple-locked--and I've got the keys." - -Tom turned as white as a sheet. - -"What's the matter, boy! Here, run, somebody! Fetch a glass of water!" - -The water was brought and thrown into Tom's face. - -"Ah, now you're all right. What was the matter with you, Tom?" - -"Oh, Judge, Injun Joe's in the cave!" - - - -CHAPTER XXXIII - -WITHIN a few minutes the news had spread, and a dozen skiff-loads of -men were on their way to McDougal's cave, and the ferryboat, well -filled with passengers, soon followed. Tom Sawyer was in the skiff that -bore Judge Thatcher. - -When the cave door was unlocked, a sorrowful sight presented itself in -the dim twilight of the place. Injun Joe lay stretched upon the ground, -dead, with his face close to the crack of the door, as if his longing -eyes had been fixed, to the latest moment, upon the light and the cheer -of the free world outside. Tom was touched, for he knew by his own -experience how this wretch had suffered. His pity was moved, but -nevertheless he felt an abounding sense of relief and security, now, -which revealed to him in a degree which he had not fully appreciated -before how vast a weight of dread had been lying upon him since the day -he lifted his voice against this bloody-minded outcast. - -Injun Joe's bowie-knife lay close by, its blade broken in two. The -great foundation-beam of the door had been chipped and hacked through, -with tedious labor; useless labor, too, it was, for the native rock -formed a sill outside it, and upon that stubborn material the knife had -wrought no effect; the only damage done was to the knife itself. But if -there had been no stony obstruction there the labor would have been -useless still, for if the beam had been wholly cut away Injun Joe could -not have squeezed his body under the door, and he knew it. So he had -only hacked that place in order to be doing something--in order to pass -the weary time--in order to employ his tortured faculties. Ordinarily -one could find half a dozen bits of candle stuck around in the crevices -of this vestibule, left there by tourists; but there were none now. The -prisoner had searched them out and eaten them. He had also contrived to -catch a few bats, and these, also, he had eaten, leaving only their -claws. The poor unfortunate had starved to death. In one place, near at -hand, a stalagmite had been slowly growing up from the ground for ages, -builded by the water-drip from a stalactite overhead. The captive had -broken off the stalagmite, and upon the stump had placed a stone, -wherein he had scooped a shallow hollow to catch the precious drop -that fell once in every three minutes with the dreary regularity of a -clock-tick--a dessertspoonful once in four and twenty hours. That drop -was falling when the Pyramids were new; when Troy fell; when the -foundations of Rome were laid; when Christ was crucified; when the -Conqueror created the British empire; when Columbus sailed; when the -massacre at Lexington was "news." It is falling now; it will still be -falling when all these things shall have sunk down the afternoon of -history, and the twilight of tradition, and been swallowed up in the -thick night of oblivion. Has everything a purpose and a mission? Did -this drop fall patiently during five thousand years to be ready for -this flitting human insect's need? and has it another important object -to accomplish ten thousand years to come? No matter. It is many and -many a year since the hapless half-breed scooped out the stone to catch -the priceless drops, but to this day the tourist stares longest at that -pathetic stone and that slow-dropping water when he comes to see the -wonders of McDougal's cave. Injun Joe's cup stands first in the list of -the cavern's marvels; even "Aladdin's Palace" cannot rival it. - -Injun Joe was buried near the mouth of the cave; and people flocked -there in boats and wagons from the towns and from all the farms and -hamlets for seven miles around; they brought their children, and all -sorts of provisions, and confessed that they had had almost as -satisfactory a time at the funeral as they could have had at the -hanging. - -This funeral stopped the further growth of one thing--the petition to -the governor for Injun Joe's pardon. The petition had been largely -signed; many tearful and eloquent meetings had been held, and a -committee of sappy women been appointed to go in deep mourning and wail -around the governor, and implore him to be a merciful ass and trample -his duty under foot. Injun Joe was believed to have killed five -citizens of the village, but what of that? If he had been Satan himself -there would have been plenty of weaklings ready to scribble their names -to a pardon-petition, and drip a tear on it from their permanently -impaired and leaky water-works. - -The morning after the funeral Tom took Huck to a private place to have -an important talk. Huck had learned all about Tom's adventure from the -Welshman and the Widow Douglas, by this time, but Tom said he reckoned -there was one thing they had not told him; that thing was what he -wanted to talk about now. Huck's face saddened. He said: - -"I know what it is. You got into No. 2 and never found anything but -whiskey. Nobody told me it was you; but I just knowed it must 'a' ben -you, soon as I heard 'bout that whiskey business; and I knowed you -hadn't got the money becuz you'd 'a' got at me some way or other and -told me even if you was mum to everybody else. Tom, something's always -told me we'd never get holt of that swag." - -"Why, Huck, I never told on that tavern-keeper. YOU know his tavern -was all right the Saturday I went to the picnic. Don't you remember you -was to watch there that night?" - -"Oh yes! Why, it seems 'bout a year ago. It was that very night that I -follered Injun Joe to the widder's." - -"YOU followed him?" - -"Yes--but you keep mum. I reckon Injun Joe's left friends behind him, -and I don't want 'em souring on me and doing me mean tricks. If it -hadn't ben for me he'd be down in Texas now, all right." - -Then Huck told his entire adventure in confidence to Tom, who had only -heard of the Welshman's part of it before. - -"Well," said Huck, presently, coming back to the main question, -"whoever nipped the whiskey in No. 2, nipped the money, too, I reckon ---anyways it's a goner for us, Tom." - -"Huck, that money wasn't ever in No. 2!" - -"What!" Huck searched his comrade's face keenly. "Tom, have you got on -the track of that money again?" - -"Huck, it's in the cave!" - -Huck's eyes blazed. - -"Say it again, Tom." - -"The money's in the cave!" - -"Tom--honest injun, now--is it fun, or earnest?" - -"Earnest, Huck--just as earnest as ever I was in my life. Will you go -in there with me and help get it out?" - -"I bet I will! I will if it's where we can blaze our way to it and not -get lost." - -"Huck, we can do that without the least little bit of trouble in the -world." - -"Good as wheat! What makes you think the money's--" - -"Huck, you just wait till we get in there. If we don't find it I'll -agree to give you my drum and every thing I've got in the world. I -will, by jings." - -"All right--it's a whiz. When do you say?" - -"Right now, if you say it. Are you strong enough?" - -"Is it far in the cave? I ben on my pins a little, three or four days, -now, but I can't walk more'n a mile, Tom--least I don't think I could." - -"It's about five mile into there the way anybody but me would go, -Huck, but there's a mighty short cut that they don't anybody but me -know about. Huck, I'll take you right to it in a skiff. I'll float the -skiff down there, and I'll pull it back again all by myself. You -needn't ever turn your hand over." - -"Less start right off, Tom." - -"All right. We want some bread and meat, and our pipes, and a little -bag or two, and two or three kite-strings, and some of these -new-fangled things they call lucifer matches. I tell you, many's -the time I wished I had some when I was in there before." - -A trifle after noon the boys borrowed a small skiff from a citizen who -was absent, and got under way at once. When they were several miles -below "Cave Hollow," Tom said: - -"Now you see this bluff here looks all alike all the way down from the -cave hollow--no houses, no wood-yards, bushes all alike. But do you see -that white place up yonder where there's been a landslide? Well, that's -one of my marks. We'll get ashore, now." - -They landed. - -"Now, Huck, where we're a-standing you could touch that hole I got out -of with a fishing-pole. See if you can find it." - -Huck searched all the place about, and found nothing. Tom proudly -marched into a thick clump of sumach bushes and said: - -"Here you are! Look at it, Huck; it's the snuggest hole in this -country. You just keep mum about it. All along I've been wanting to be -a robber, but I knew I'd got to have a thing like this, and where to -run across it was the bother. We've got it now, and we'll keep it -quiet, only we'll let Joe Harper and Ben Rogers in--because of course -there's got to be a Gang, or else there wouldn't be any style about it. -Tom Sawyer's Gang--it sounds splendid, don't it, Huck?" - -"Well, it just does, Tom. And who'll we rob?" - -"Oh, most anybody. Waylay people--that's mostly the way." - -"And kill them?" - -"No, not always. Hive them in the cave till they raise a ransom." - -"What's a ransom?" - -"Money. You make them raise all they can, off'n their friends; and -after you've kept them a year, if it ain't raised then you kill them. -That's the general way. Only you don't kill the women. You shut up the -women, but you don't kill them. They're always beautiful and rich, and -awfully scared. You take their watches and things, but you always take -your hat off and talk polite. They ain't anybody as polite as robbers ---you'll see that in any book. Well, the women get to loving you, and -after they've been in the cave a week or two weeks they stop crying and -after that you couldn't get them to leave. If you drove them out they'd -turn right around and come back. It's so in all the books." - -"Why, it's real bully, Tom. I believe it's better'n to be a pirate." - -"Yes, it's better in some ways, because it's close to home and -circuses and all that." - -By this time everything was ready and the boys entered the hole, Tom -in the lead. They toiled their way to the farther end of the tunnel, -then made their spliced kite-strings fast and moved on. A few steps -brought them to the spring, and Tom felt a shudder quiver all through -him. He showed Huck the fragment of candle-wick perched on a lump of -clay against the wall, and described how he and Becky had watched the -flame struggle and expire. - -The boys began to quiet down to whispers, now, for the stillness and -gloom of the place oppressed their spirits. They went on, and presently -entered and followed Tom's other corridor until they reached the -"jumping-off place." The candles revealed the fact that it was not -really a precipice, but only a steep clay hill twenty or thirty feet -high. Tom whispered: - -"Now I'll show you something, Huck." - -He held his candle aloft and said: - -"Look as far around the corner as you can. Do you see that? There--on -the big rock over yonder--done with candle-smoke." - -"Tom, it's a CROSS!" - -"NOW where's your Number Two? 'UNDER THE CROSS,' hey? Right yonder's -where I saw Injun Joe poke up his candle, Huck!" - -Huck stared at the mystic sign awhile, and then said with a shaky voice: - -"Tom, less git out of here!" - -"What! and leave the treasure?" - -"Yes--leave it. Injun Joe's ghost is round about there, certain." - -"No it ain't, Huck, no it ain't. It would ha'nt the place where he -died--away out at the mouth of the cave--five mile from here." - -"No, Tom, it wouldn't. It would hang round the money. I know the ways -of ghosts, and so do you." - -Tom began to fear that Huck was right. Misgivings gathered in his -mind. But presently an idea occurred to him-- - -"Lookyhere, Huck, what fools we're making of ourselves! Injun Joe's -ghost ain't a going to come around where there's a cross!" - -The point was well taken. It had its effect. - -"Tom, I didn't think of that. But that's so. It's luck for us, that -cross is. I reckon we'll climb down there and have a hunt for that box." - -Tom went first, cutting rude steps in the clay hill as he descended. -Huck followed. Four avenues opened out of the small cavern which the -great rock stood in. The boys examined three of them with no result. -They found a small recess in the one nearest the base of the rock, with -a pallet of blankets spread down in it; also an old suspender, some -bacon rind, and the well-gnawed bones of two or three fowls. But there -was no money-box. The lads searched and researched this place, but in -vain. Tom said: - -"He said UNDER the cross. Well, this comes nearest to being under the -cross. It can't be under the rock itself, because that sets solid on -the ground." - -They searched everywhere once more, and then sat down discouraged. -Huck could suggest nothing. By-and-by Tom said: - -"Lookyhere, Huck, there's footprints and some candle-grease on the -clay about one side of this rock, but not on the other sides. Now, -what's that for? I bet you the money IS under the rock. I'm going to -dig in the clay." - -"That ain't no bad notion, Tom!" said Huck with animation. - -Tom's "real Barlow" was out at once, and he had not dug four inches -before he struck wood. - -"Hey, Huck!--you hear that?" - -Huck began to dig and scratch now. Some boards were soon uncovered and -removed. They had concealed a natural chasm which led under the rock. -Tom got into this and held his candle as far under the rock as he -could, but said he could not see to the end of the rift. He proposed to -explore. He stooped and passed under; the narrow way descended -gradually. He followed its winding course, first to the right, then to -the left, Huck at his heels. Tom turned a short curve, by-and-by, and -exclaimed: - -"My goodness, Huck, lookyhere!" - -It was the treasure-box, sure enough, occupying a snug little cavern, -along with an empty powder-keg, a couple of guns in leather cases, two -or three pairs of old moccasins, a leather belt, and some other rubbish -well soaked with the water-drip. - -"Got it at last!" said Huck, ploughing among the tarnished coins with -his hand. "My, but we're rich, Tom!" - -"Huck, I always reckoned we'd get it. It's just too good to believe, -but we HAVE got it, sure! Say--let's not fool around here. Let's snake -it out. Lemme see if I can lift the box." - -It weighed about fifty pounds. Tom could lift it, after an awkward -fashion, but could not carry it conveniently. - -"I thought so," he said; "THEY carried it like it was heavy, that day -at the ha'nted house. I noticed that. I reckon I was right to think of -fetching the little bags along." - -The money was soon in the bags and the boys took it up to the cross -rock. - -"Now less fetch the guns and things," said Huck. - -"No, Huck--leave them there. They're just the tricks to have when we -go to robbing. We'll keep them there all the time, and we'll hold our -orgies there, too. It's an awful snug place for orgies." - -"What orgies?" - -"I dono. But robbers always have orgies, and of course we've got to -have them, too. Come along, Huck, we've been in here a long time. It's -getting late, I reckon. I'm hungry, too. We'll eat and smoke when we -get to the skiff." - -They presently emerged into the clump of sumach bushes, looked warily -out, found the coast clear, and were soon lunching and smoking in the -skiff. As the sun dipped toward the horizon they pushed out and got -under way. Tom skimmed up the shore through the long twilight, chatting -cheerily with Huck, and landed shortly after dark. - -"Now, Huck," said Tom, "we'll hide the money in the loft of the -widow's woodshed, and I'll come up in the morning and we'll count it -and divide, and then we'll hunt up a place out in the woods for it -where it will be safe. Just you lay quiet here and watch the stuff till -I run and hook Benny Taylor's little wagon; I won't be gone a minute." - -He disappeared, and presently returned with the wagon, put the two -small sacks into it, threw some old rags on top of them, and started -off, dragging his cargo behind him. When the boys reached the -Welshman's house, they stopped to rest. Just as they were about to move -on, the Welshman stepped out and said: - -"Hallo, who's that?" - -"Huck and Tom Sawyer." - -"Good! Come along with me, boys, you are keeping everybody waiting. -Here--hurry up, trot ahead--I'll haul the wagon for you. Why, it's not -as light as it might be. Got bricks in it?--or old metal?" - -"Old metal," said Tom. - -"I judged so; the boys in this town will take more trouble and fool -away more time hunting up six bits' worth of old iron to sell to the -foundry than they would to make twice the money at regular work. But -that's human nature--hurry along, hurry along!" - -The boys wanted to know what the hurry was about. - -"Never mind; you'll see, when we get to the Widow Douglas'." - -Huck said with some apprehension--for he was long used to being -falsely accused: - -"Mr. Jones, we haven't been doing nothing." - -The Welshman laughed. - -"Well, I don't know, Huck, my boy. I don't know about that. Ain't you -and the widow good friends?" - -"Yes. Well, she's ben good friends to me, anyway." - -"All right, then. What do you want to be afraid for?" - -This question was not entirely answered in Huck's slow mind before he -found himself pushed, along with Tom, into Mrs. Douglas' drawing-room. -Mr. Jones left the wagon near the door and followed. - -The place was grandly lighted, and everybody that was of any -consequence in the village was there. The Thatchers were there, the -Harpers, the Rogerses, Aunt Polly, Sid, Mary, the minister, the editor, -and a great many more, and all dressed in their best. The widow -received the boys as heartily as any one could well receive two such -looking beings. They were covered with clay and candle-grease. Aunt -Polly blushed crimson with humiliation, and frowned and shook her head -at Tom. Nobody suffered half as much as the two boys did, however. Mr. -Jones said: - -"Tom wasn't at home, yet, so I gave him up; but I stumbled on him and -Huck right at my door, and so I just brought them along in a hurry." - -"And you did just right," said the widow. "Come with me, boys." - -She took them to a bedchamber and said: - -"Now wash and dress yourselves. Here are two new suits of clothes ---shirts, socks, everything complete. They're Huck's--no, no thanks, -Huck--Mr. Jones bought one and I the other. But they'll fit both of you. -Get into them. We'll wait--come down when you are slicked up enough." - -Then she left. - - - -CHAPTER XXXIV - -HUCK said: "Tom, we can slope, if we can find a rope. The window ain't -high from the ground." - -"Shucks! what do you want to slope for?" - -"Well, I ain't used to that kind of a crowd. I can't stand it. I ain't -going down there, Tom." - -"Oh, bother! It ain't anything. I don't mind it a bit. I'll take care -of you." - -Sid appeared. - -"Tom," said he, "auntie has been waiting for you all the afternoon. -Mary got your Sunday clothes ready, and everybody's been fretting about -you. Say--ain't this grease and clay, on your clothes?" - -"Now, Mr. Siddy, you jist 'tend to your own business. What's all this -blow-out about, anyway?" - -"It's one of the widow's parties that she's always having. This time -it's for the Welshman and his sons, on account of that scrape they -helped her out of the other night. And say--I can tell you something, -if you want to know." - -"Well, what?" - -"Why, old Mr. Jones is going to try to spring something on the people -here to-night, but I overheard him tell auntie to-day about it, as a -secret, but I reckon it's not much of a secret now. Everybody knows ---the widow, too, for all she tries to let on she don't. Mr. Jones was -bound Huck should be here--couldn't get along with his grand secret -without Huck, you know!" - -"Secret about what, Sid?" - -"About Huck tracking the robbers to the widow's. I reckon Mr. Jones -was going to make a grand time over his surprise, but I bet you it will -drop pretty flat." - -Sid chuckled in a very contented and satisfied way. - -"Sid, was it you that told?" - -"Oh, never mind who it was. SOMEBODY told--that's enough." - -"Sid, there's only one person in this town mean enough to do that, and -that's you. If you had been in Huck's place you'd 'a' sneaked down the -hill and never told anybody on the robbers. You can't do any but mean -things, and you can't bear to see anybody praised for doing good ones. -There--no thanks, as the widow says"--and Tom cuffed Sid's ears and -helped him to the door with several kicks. "Now go and tell auntie if -you dare--and to-morrow you'll catch it!" - -Some minutes later the widow's guests were at the supper-table, and a -dozen children were propped up at little side-tables in the same room, -after the fashion of that country and that day. At the proper time Mr. -Jones made his little speech, in which he thanked the widow for the -honor she was doing himself and his sons, but said that there was -another person whose modesty-- - -And so forth and so on. He sprung his secret about Huck's share in the -adventure in the finest dramatic manner he was master of, but the -surprise it occasioned was largely counterfeit and not as clamorous and -effusive as it might have been under happier circumstances. However, -the widow made a pretty fair show of astonishment, and heaped so many -compliments and so much gratitude upon Huck that he almost forgot the -nearly intolerable discomfort of his new clothes in the entirely -intolerable discomfort of being set up as a target for everybody's gaze -and everybody's laudations. - -The widow said she meant to give Huck a home under her roof and have -him educated; and that when she could spare the money she would start -him in business in a modest way. Tom's chance was come. He said: - -"Huck don't need it. Huck's rich." - -Nothing but a heavy strain upon the good manners of the company kept -back the due and proper complimentary laugh at this pleasant joke. But -the silence was a little awkward. Tom broke it: - -"Huck's got money. Maybe you don't believe it, but he's got lots of -it. Oh, you needn't smile--I reckon I can show you. You just wait a -minute." - -Tom ran out of doors. The company looked at each other with a -perplexed interest--and inquiringly at Huck, who was tongue-tied. - -"Sid, what ails Tom?" said Aunt Polly. "He--well, there ain't ever any -making of that boy out. I never--" - -Tom entered, struggling with the weight of his sacks, and Aunt Polly -did not finish her sentence. Tom poured the mass of yellow coin upon -the table and said: - -"There--what did I tell you? Half of it's Huck's and half of it's mine!" - -The spectacle took the general breath away. All gazed, nobody spoke -for a moment. Then there was a unanimous call for an explanation. Tom -said he could furnish it, and he did. The tale was long, but brimful of -interest. There was scarcely an interruption from any one to break the -charm of its flow. When he had finished, Mr. Jones said: - -"I thought I had fixed up a little surprise for this occasion, but it -don't amount to anything now. This one makes it sing mighty small, I'm -willing to allow." - -The money was counted. The sum amounted to a little over twelve -thousand dollars. It was more than any one present had ever seen at one -time before, though several persons were there who were worth -considerably more than that in property. - - - -CHAPTER XXXV - -THE reader may rest satisfied that Tom's and Huck's windfall made a -mighty stir in the poor little village of St. Petersburg. So vast a -sum, all in actual cash, seemed next to incredible. It was talked -about, gloated over, glorified, until the reason of many of the -citizens tottered under the strain of the unhealthy excitement. Every -"haunted" house in St. Petersburg and the neighboring villages was -dissected, plank by plank, and its foundations dug up and ransacked for -hidden treasure--and not by boys, but men--pretty grave, unromantic -men, too, some of them. Wherever Tom and Huck appeared they were -courted, admired, stared at. The boys were not able to remember that -their remarks had possessed weight before; but now their sayings were -treasured and repeated; everything they did seemed somehow to be -regarded as remarkable; they had evidently lost the power of doing and -saying commonplace things; moreover, their past history was raked up -and discovered to bear marks of conspicuous originality. The village -paper published biographical sketches of the boys. - -The Widow Douglas put Huck's money out at six per cent., and Judge -Thatcher did the same with Tom's at Aunt Polly's request. Each lad had -an income, now, that was simply prodigious--a dollar for every week-day -in the year and half of the Sundays. It was just what the minister got ---no, it was what he was promised--he generally couldn't collect it. A -dollar and a quarter a week would board, lodge, and school a boy in -those old simple days--and clothe him and wash him, too, for that -matter. - -Judge Thatcher had conceived a great opinion of Tom. He said that no -commonplace boy would ever have got his daughter out of the cave. When -Becky told her father, in strict confidence, how Tom had taken her -whipping at school, the Judge was visibly moved; and when she pleaded -grace for the mighty lie which Tom had told in order to shift that -whipping from her shoulders to his own, the Judge said with a fine -outburst that it was a noble, a generous, a magnanimous lie--a lie that -was worthy to hold up its head and march down through history breast to -breast with George Washington's lauded Truth about the hatchet! Becky -thought her father had never looked so tall and so superb as when he -walked the floor and stamped his foot and said that. She went straight -off and told Tom about it. - -Judge Thatcher hoped to see Tom a great lawyer or a great soldier some -day. He said he meant to look to it that Tom should be admitted to the -National Military Academy and afterward trained in the best law school -in the country, in order that he might be ready for either career or -both. - -Huck Finn's wealth and the fact that he was now under the Widow -Douglas' protection introduced him into society--no, dragged him into -it, hurled him into it--and his sufferings were almost more than he -could bear. The widow's servants kept him clean and neat, combed and -brushed, and they bedded him nightly in unsympathetic sheets that had -not one little spot or stain which he could press to his heart and know -for a friend. He had to eat with a knife and fork; he had to use -napkin, cup, and plate; he had to learn his book, he had to go to -church; he had to talk so properly that speech was become insipid in -his mouth; whithersoever he turned, the bars and shackles of -civilization shut him in and bound him hand and foot. - -He bravely bore his miseries three weeks, and then one day turned up -missing. For forty-eight hours the widow hunted for him everywhere in -great distress. The public were profoundly concerned; they searched -high and low, they dragged the river for his body. Early the third -morning Tom Sawyer wisely went poking among some old empty hogsheads -down behind the abandoned slaughter-house, and in one of them he found -the refugee. Huck had slept there; he had just breakfasted upon some -stolen odds and ends of food, and was lying off, now, in comfort, with -his pipe. He was unkempt, uncombed, and clad in the same old ruin of -rags that had made him picturesque in the days when he was free and -happy. Tom routed him out, told him the trouble he had been causing, -and urged him to go home. Huck's face lost its tranquil content, and -took a melancholy cast. He said: - -"Don't talk about it, Tom. I've tried it, and it don't work; it don't -work, Tom. It ain't for me; I ain't used to it. The widder's good to -me, and friendly; but I can't stand them ways. She makes me get up just -at the same time every morning; she makes me wash, they comb me all to -thunder; she won't let me sleep in the woodshed; I got to wear them -blamed clothes that just smothers me, Tom; they don't seem to any air -git through 'em, somehow; and they're so rotten nice that I can't set -down, nor lay down, nor roll around anywher's; I hain't slid on a -cellar-door for--well, it 'pears to be years; I got to go to church and -sweat and sweat--I hate them ornery sermons! I can't ketch a fly in -there, I can't chaw. I got to wear shoes all Sunday. The widder eats by -a bell; she goes to bed by a bell; she gits up by a bell--everything's -so awful reg'lar a body can't stand it." - -"Well, everybody does that way, Huck." - -"Tom, it don't make no difference. I ain't everybody, and I can't -STAND it. It's awful to be tied up so. And grub comes too easy--I don't -take no interest in vittles, that way. I got to ask to go a-fishing; I -got to ask to go in a-swimming--dern'd if I hain't got to ask to do -everything. Well, I'd got to talk so nice it wasn't no comfort--I'd got -to go up in the attic and rip out awhile, every day, to git a taste in -my mouth, or I'd a died, Tom. The widder wouldn't let me smoke; she -wouldn't let me yell, she wouldn't let me gape, nor stretch, nor -scratch, before folks--" [Then with a spasm of special irritation and -injury]--"And dad fetch it, she prayed all the time! I never see such a -woman! I HAD to shove, Tom--I just had to. And besides, that school's -going to open, and I'd a had to go to it--well, I wouldn't stand THAT, -Tom. Looky here, Tom, being rich ain't what it's cracked up to be. It's -just worry and worry, and sweat and sweat, and a-wishing you was dead -all the time. Now these clothes suits me, and this bar'l suits me, and -I ain't ever going to shake 'em any more. Tom, I wouldn't ever got into -all this trouble if it hadn't 'a' ben for that money; now you just take -my sheer of it along with your'n, and gimme a ten-center sometimes--not -many times, becuz I don't give a dern for a thing 'thout it's tollable -hard to git--and you go and beg off for me with the widder." - -"Oh, Huck, you know I can't do that. 'Tain't fair; and besides if -you'll try this thing just a while longer you'll come to like it." - -"Like it! Yes--the way I'd like a hot stove if I was to set on it long -enough. No, Tom, I won't be rich, and I won't live in them cussed -smothery houses. I like the woods, and the river, and hogsheads, and -I'll stick to 'em, too. Blame it all! just as we'd got guns, and a -cave, and all just fixed to rob, here this dern foolishness has got to -come up and spile it all!" - -Tom saw his opportunity-- - -"Lookyhere, Huck, being rich ain't going to keep me back from turning -robber." - -"No! Oh, good-licks; are you in real dead-wood earnest, Tom?" - -"Just as dead earnest as I'm sitting here. But Huck, we can't let you -into the gang if you ain't respectable, you know." - -Huck's joy was quenched. - -"Can't let me in, Tom? Didn't you let me go for a pirate?" - -"Yes, but that's different. A robber is more high-toned than what a -pirate is--as a general thing. In most countries they're awful high up -in the nobility--dukes and such." - -"Now, Tom, hain't you always ben friendly to me? You wouldn't shet me -out, would you, Tom? You wouldn't do that, now, WOULD you, Tom?" - -"Huck, I wouldn't want to, and I DON'T want to--but what would people -say? Why, they'd say, 'Mph! Tom Sawyer's Gang! pretty low characters in -it!' They'd mean you, Huck. You wouldn't like that, and I wouldn't." - -Huck was silent for some time, engaged in a mental struggle. Finally -he said: - -"Well, I'll go back to the widder for a month and tackle it and see if -I can come to stand it, if you'll let me b'long to the gang, Tom." - -"All right, Huck, it's a whiz! Come along, old chap, and I'll ask the -widow to let up on you a little, Huck." - -"Will you, Tom--now will you? That's good. If she'll let up on some of -the roughest things, I'll smoke private and cuss private, and crowd -through or bust. When you going to start the gang and turn robbers?" - -"Oh, right off. We'll get the boys together and have the initiation -to-night, maybe." - -"Have the which?" - -"Have the initiation." - -"What's that?" - -"It's to swear to stand by one another, and never tell the gang's -secrets, even if you're chopped all to flinders, and kill anybody and -all his family that hurts one of the gang." - -"That's gay--that's mighty gay, Tom, I tell you." - -"Well, I bet it is. And all that swearing's got to be done at -midnight, in the lonesomest, awfulest place you can find--a ha'nted -house is the best, but they're all ripped up now." - -"Well, midnight's good, anyway, Tom." - -"Yes, so it is. And you've got to swear on a coffin, and sign it with -blood." - -"Now, that's something LIKE! Why, it's a million times bullier than -pirating. I'll stick to the widder till I rot, Tom; and if I git to be -a reg'lar ripper of a robber, and everybody talking 'bout it, I reckon -she'll be proud she snaked me in out of the wet." - - - -CONCLUSION - -SO endeth this chronicle. It being strictly a history of a BOY, it -must stop here; the story could not go much further without becoming -the history of a MAN. When one writes a novel about grown people, he -knows exactly where to stop--that is, with a marriage; but when he -writes of juveniles, he must stop where he best can. - -Most of the characters that perform in this book still live, and are -prosperous and happy. Some day it may seem worth while to take up the -story of the younger ones again and see what sort of men and women they -turned out to be; therefore it will be wisest not to reveal any of that -part of their lives at present. diff --git a/src/net/textproto/reader_test.go b/src/net/textproto/reader_test.go index 7cff7b4579..f85fbdc36d 100644 --- a/src/net/textproto/reader_test.go +++ b/src/net/textproto/reader_test.go @@ -382,31 +382,25 @@ Non-Interned: test func BenchmarkReadMIMEHeader(b *testing.B) { b.ReportAllocs() - var buf bytes.Buffer - br := bufio.NewReader(&buf) - r := NewReader(br) - for i := 0; i < b.N; i++ { - var want int - var find string - if (i & 1) == 1 { - buf.WriteString(clientHeaders) - want = 10 - find = "Cookie" - } else { - buf.WriteString(serverHeaders) - want = 9 - find = "Via" - } - h, err := r.ReadMIMEHeader() - if err != nil { - b.Fatal(err) - } - if len(h) != want { - b.Fatalf("wrong number of headers: got %d, want %d", len(h), want) - } - if _, ok := h[find]; !ok { - b.Fatalf("did not find key %s", find) - } + for _, set := range []struct { + name string + headers string + }{ + {"client_headers", clientHeaders}, + {"server_headers", serverHeaders}, + } { + b.Run(set.name, func(b *testing.B) { + var buf bytes.Buffer + br := bufio.NewReader(&buf) + r := NewReader(br) + + for i := 0; i < b.N; i++ { + buf.WriteString(set.headers) + if _, err := r.ReadMIMEHeader(); err != nil { + b.Fatal(err) + } + } + }) } } diff --git a/src/net/unixsock_windows_test.go b/src/net/unixsock_windows_test.go index a1da5d4062..d856e3fd81 100644 --- a/src/net/unixsock_windows_test.go +++ b/src/net/unixsock_windows_test.go @@ -10,6 +10,7 @@ import ( "internal/syscall/windows/registry" "os" "reflect" + "runtime" "strconv" "testing" ) @@ -33,6 +34,9 @@ func isBuild17063() bool { } func TestUnixConnLocalWindows(t *testing.T) { + if runtime.GOARCH == "386" { + t.Skip("not supported on windows/386, see golang.org/issue/27943") + } if !isBuild17063() { t.Skip("unix test") } diff --git a/src/net/url/example_test.go b/src/net/url/example_test.go index d8eb6dcd20..ad67f5328a 100644 --- a/src/net/url/example_test.go +++ b/src/net/url/example_test.go @@ -219,5 +219,5 @@ func toJSON(m interface{}) string { if err != nil { log.Fatal(err) } - return strings.Replace(string(js), ",", ", ", -1) + return strings.ReplaceAll(string(js), ",", ", ") } diff --git a/src/net/url/url.go b/src/net/url/url.go index 4943ea6d67..702f9124bf 100644 --- a/src/net/url/url.go +++ b/src/net/url/url.go @@ -304,7 +304,26 @@ func escape(s string, mode encoding) string { return s } - t := make([]byte, len(s)+2*hexCount) + var buf [64]byte + var t []byte + + required := len(s) + 2*hexCount + if required <= len(buf) { + t = buf[:required] + } else { + t = make([]byte, required) + } + + if hexCount == 0 { + copy(t, s) + for i := 0; i < len(s); i++ { + if s[i] == ' ' { + t[i] = '+' + } + } + return string(t) + } + j := 0 for i := 0; i < len(s); i++ { switch c := s[i]; { @@ -515,13 +534,7 @@ func parse(rawurl string, viaRequest bool) (*URL, error) { url.ForceQuery = true rest = rest[:len(rest)-1] } else { - var q string - rest, q = split(rest, "?", true) - if validQuery(q) { - url.RawQuery = q - } else { - url.RawQuery = QueryEscape(q) - } + rest, url.RawQuery = split(rest, "?", true) } if !strings.HasPrefix(rest, "/") { @@ -1120,46 +1133,3 @@ func validUserinfo(s string) bool { } return true } - -// validQuery reports whether s is a valid query string per RFC 3986 -// Section 3.4: -// query = *( pchar / "/" / "?" ) -// pchar = unreserved / pct-encoded / sub-delims / ":" / "@" -// unreserved = ALPHA / DIGIT / "-" / "." / "_" / "~" -// sub-delims = "!" / "$" / "&" / "'" / "(" / ")" -// / "*" / "+" / "," / ";" / "=" -func validQuery(s string) bool { - pctEnc := 0 - - for _, r := range s { - if pctEnc > 0 { - if uint32(r) > 255 || !ishex(byte(r)) { - return false - } - pctEnc-- - continue - } else if r == '%' { - pctEnc = 2 - continue - } - - if 'A' <= r && r <= 'Z' { - continue - } - if 'a' <= r && r <= 'z' { - continue - } - if '0' <= r && r <= '9' { - continue - } - switch r { - case '-', '.', '_', '~', '!', '$', '&', '\'', '(', ')', - '*', '+', ',', ';', '=', ':', '@', '/', '?': - continue - default: - return false - } - } - - return true -} diff --git a/src/net/url/url_test.go b/src/net/url/url_test.go index 19d4d636d6..7c4ada245a 100644 --- a/src/net/url/url_test.go +++ b/src/net/url/url_test.go @@ -590,16 +590,6 @@ var urltests = []URLTest{ }, "mailto:?subject=hi", }, - { - "https://example.com/search?q=Фотки собак&source=lnms", - &URL{ - Scheme: "https", - Host: "example.com", - Path: "/search", - RawQuery: "q%3D%D0%A4%D0%BE%D1%82%D0%BA%D0%B8+%D1%81%D0%BE%D0%B1%D0%B0%D0%BA%26source%3Dlnms", - }, - "https://example.com/search?q%3D%D0%A4%D0%BE%D1%82%D0%BA%D0%B8+%D1%81%D0%BE%D0%B1%D0%B0%D0%BA%26source%3Dlnms", - }, } // more useful string for debugging than fmt's struct printer @@ -858,18 +848,18 @@ func TestUnescape(t *testing.T) { in := tt.in out := tt.out if strings.Contains(tt.in, "+") { - in = strings.Replace(tt.in, "+", "%20", -1) + in = strings.ReplaceAll(tt.in, "+", "%20") actual, err := PathUnescape(in) if actual != tt.out || (err != nil) != (tt.err != nil) { t.Errorf("PathUnescape(%q) = %q, %s; want %q, %s", in, actual, err, tt.out, tt.err) } if tt.err == nil { - s, err := QueryUnescape(strings.Replace(tt.in, "+", "XXX", -1)) + s, err := QueryUnescape(strings.ReplaceAll(tt.in, "+", "XXX")) if err != nil { continue } in = tt.in - out = strings.Replace(s, "XXX", "+", -1) + out = strings.ReplaceAll(s, "XXX", "+") } } @@ -1449,7 +1439,6 @@ func TestParseErrors(t *testing.T) { {"cache_object:foo", true}, {"cache_object:foo/bar", true}, {"cache_object/:foo/bar", false}, - {"https://example.com/search?q=Фотки собак&source=lnms", false}, } for _, tt := range tests { u, err := Parse(tt.in) @@ -1754,3 +1743,106 @@ func TestInvalidUserPassword(t *testing.T) { t.Errorf("error = %q; want substring %q", got, wantsub) } } + +var escapeBenchmarks = []struct { + unescaped string + query string + path string +}{ + { + unescaped: "one two", + query: "one+two", + path: "one%20two", + }, + { + unescaped: "Фотки собак", + query: "%D0%A4%D0%BE%D1%82%D0%BA%D0%B8+%D1%81%D0%BE%D0%B1%D0%B0%D0%BA", + path: "%D0%A4%D0%BE%D1%82%D0%BA%D0%B8%20%D1%81%D0%BE%D0%B1%D0%B0%D0%BA", + }, + + { + unescaped: "shortrun(break)shortrun", + query: "shortrun%28break%29shortrun", + path: "shortrun%28break%29shortrun", + }, + + { + unescaped: "longerrunofcharacters(break)anotherlongerrunofcharacters", + query: "longerrunofcharacters%28break%29anotherlongerrunofcharacters", + path: "longerrunofcharacters%28break%29anotherlongerrunofcharacters", + }, + + { + unescaped: strings.Repeat("padded/with+various%characters?that=need$some@escaping+paddedsowebreak/256bytes", 4), + query: strings.Repeat("padded%2Fwith%2Bvarious%25characters%3Fthat%3Dneed%24some%40escaping%2Bpaddedsowebreak%2F256bytes", 4), + path: strings.Repeat("padded%2Fwith+various%25characters%3Fthat=need$some@escaping+paddedsowebreak%2F256bytes", 4), + }, +} + +func BenchmarkQueryEscape(b *testing.B) { + for _, tc := range escapeBenchmarks { + b.Run("", func(b *testing.B) { + b.ReportAllocs() + var g string + for i := 0; i < b.N; i++ { + g = QueryEscape(tc.unescaped) + } + b.StopTimer() + if g != tc.query { + b.Errorf("QueryEscape(%q) == %q, want %q", tc.unescaped, g, tc.query) + } + + }) + } +} + +func BenchmarkPathEscape(b *testing.B) { + for _, tc := range escapeBenchmarks { + b.Run("", func(b *testing.B) { + b.ReportAllocs() + var g string + for i := 0; i < b.N; i++ { + g = PathEscape(tc.unescaped) + } + b.StopTimer() + if g != tc.path { + b.Errorf("PathEscape(%q) == %q, want %q", tc.unescaped, g, tc.path) + } + + }) + } +} + +func BenchmarkQueryUnescape(b *testing.B) { + for _, tc := range escapeBenchmarks { + b.Run("", func(b *testing.B) { + b.ReportAllocs() + var g string + for i := 0; i < b.N; i++ { + g, _ = QueryUnescape(tc.query) + } + b.StopTimer() + if g != tc.unescaped { + b.Errorf("QueryUnescape(%q) == %q, want %q", tc.query, g, tc.unescaped) + } + + }) + } +} + +func BenchmarkPathUnescape(b *testing.B) { + for _, tc := range escapeBenchmarks { + b.Run("", func(b *testing.B) { + b.ReportAllocs() + var g string + for i := 0; i < b.N; i++ { + g, _ = PathUnescape(tc.path) + } + b.StopTimer() + if g != tc.unescaped { + b.Errorf("PathUnescape(%q) == %q, want %q", tc.path, g, tc.unescaped) + } + + }) + } +} diff --git a/src/os/example_test.go b/src/os/example_test.go index 95a4a67817..5c96ebb417 100644 --- a/src/os/example_test.go +++ b/src/os/example_test.go @@ -76,32 +76,29 @@ func ExampleIsNotExist() { // file does not exist } -func init() { - os.Setenv("USER", "gopher") - os.Setenv("HOME", "/usr/gopher") - os.Unsetenv("GOPATH") -} - func ExampleExpand() { mapper := func(placeholderName string) string { switch placeholderName { case "DAY_PART": return "morning" - case "USER": + case "NAME": return "Gopher" } return "" } - fmt.Println(os.Expand("Good ${DAY_PART}, $USER!", mapper)) + fmt.Println(os.Expand("Good ${DAY_PART}, $NAME!", mapper)) // Output: // Good morning, Gopher! } func ExampleExpandEnv() { - fmt.Println(os.ExpandEnv("$USER lives in ${HOME}.")) + os.Setenv("NAME", "gopher") + os.Setenv("BURROW", "/usr/gopher") + + fmt.Println(os.ExpandEnv("$NAME lives in ${BURROW}.")) // Output: // gopher lives in /usr/gopher. @@ -117,16 +114,24 @@ func ExampleLookupEnv() { } } - show("USER") - show("GOPATH") + os.Setenv("SOME_KEY", "value") + os.Setenv("EMPTY_KEY", "") + + show("SOME_KEY") + show("EMPTY_KEY") + show("MISSING_KEY") // Output: - // USER=gopher - // GOPATH not set + // SOME_KEY=value + // EMPTY_KEY= + // MISSING_KEY not set } func ExampleGetenv() { - fmt.Printf("%s lives in %s.\n", os.Getenv("USER"), os.Getenv("HOME")) + os.Setenv("NAME", "gopher") + os.Setenv("BURROW", "/usr/gopher") + + fmt.Printf("%s lives in %s.\n", os.Getenv("NAME"), os.Getenv("BURROW")) // Output: // gopher lives in /usr/gopher. diff --git a/src/os/file.go b/src/os/file.go index cba70d78fb..eb2277dece 100644 --- a/src/os/file.go +++ b/src/os/file.go @@ -381,6 +381,24 @@ func UserCacheDir() (string, error) { return dir, nil } +// UserHomeDir returns the current user's home directory. +// +// On Unix, including macOS, it returns the $HOME environment variable. +// On Windows, it returns the concatenation of %HOMEDRIVE% and %HOMEPATH%. +// On Plan 9, it returns the $home environment variable. +func UserHomeDir() string { + if runtime.GOOS == "windows" { + return Getenv("HOMEDRIVE") + Getenv("HOMEPATH") + } + if runtime.GOOS == "plan9" { + return Getenv("home") + } + if runtime.GOOS == "nacl" { + return "/" + } + return Getenv("HOME") +} + // Chmod changes the mode of the named file to mode. // If the file is a symbolic link, it changes the mode of the link's target. // If there is an error, it will be of type *PathError. diff --git a/src/os/os_test.go b/src/os/os_test.go index 894105a886..08853691a9 100644 --- a/src/os/os_test.go +++ b/src/os/os_test.go @@ -2333,3 +2333,17 @@ func TestDoubleCloseError(t *testing.T) { t.Logf("second close returned expected error %q", err) } } + +func TestUserHomeDir(t *testing.T) { + dir := UserHomeDir() + if dir == "" { + t.Fatal("UserHomeDir returned an empty string") + } + fi, err := Stat(dir) + if err != nil { + t.Fatal(err) + } + if !fi.IsDir() { + t.Fatalf("dir %s is not directory; type = %v", dir, fi.Mode()) + } +} diff --git a/src/os/os_unix_test.go b/src/os/os_unix_test.go index 54f121ef4c..1077d78613 100644 --- a/src/os/os_unix_test.go +++ b/src/os/os_unix_test.go @@ -234,7 +234,7 @@ func newFileTest(t *testing.T, blocking bool) { } defer syscall.Close(p[1]) - // Set the the read-side to non-blocking. + // Set the read-side to non-blocking. if !blocking { if err := syscall.SetNonblock(p[0], true); err != nil { syscall.Close(p[0]) diff --git a/src/os/os_windows_test.go b/src/os/os_windows_test.go index 8984dd2c66..c555369488 100644 --- a/src/os/os_windows_test.go +++ b/src/os/os_windows_test.go @@ -895,16 +895,6 @@ func main() { } } -func testIsDir(t *testing.T, path string, fi os.FileInfo) { - t.Helper() - if !fi.IsDir() { - t.Errorf("%q should be a directory", path) - } - if fi.Mode()&os.ModeSymlink != 0 { - t.Errorf("%q should not be a symlink", path) - } -} - func findOneDriveDir() (string, error) { // as per https://stackoverflow.com/questions/42519624/how-to-determine-location-of-onedrive-on-windows-7-and-8-in-c const onedrivekey = `SOFTWARE\Microsoft\OneDrive` @@ -927,57 +917,7 @@ func TestOneDrive(t *testing.T) { if err != nil { t.Skipf("Skipping, because we did not find OneDrive directory: %v", err) } - - // test os.Stat - fi, err := os.Stat(dir) - if err != nil { - t.Fatal(err) - } - testIsDir(t, dir, fi) - - // test os.Lstat - fi, err = os.Lstat(dir) - if err != nil { - t.Fatal(err) - } - testIsDir(t, dir, fi) - - // test os.File.Stat - f, err := os.Open(dir) - if err != nil { - t.Fatal(err) - } - defer f.Close() - - fi, err = f.Stat() - if err != nil { - t.Fatal(err) - } - testIsDir(t, dir, fi) - - // test os.FileInfo returned by os.Readdir - parent, err := os.Open(filepath.Dir(dir)) - if err != nil { - t.Fatal(err) - } - defer parent.Close() - - fis, err := parent.Readdir(-1) - if err != nil { - t.Fatal(err) - } - fi = nil - base := filepath.Base(dir) - for _, fi2 := range fis { - if fi2.Name() == base { - fi = fi2 - break - } - } - if fi == nil { - t.Errorf("failed to find %q in its parent", dir) - } - testIsDir(t, dir, fi) + testDirStats(t, dir) } func TestWindowsDevNullFile(t *testing.T) { diff --git a/src/os/path_windows_test.go b/src/os/path_windows_test.go index 00a3e63bf3..f1745ad132 100644 --- a/src/os/path_windows_test.go +++ b/src/os/path_windows_test.go @@ -38,10 +38,10 @@ func TestFixLongPath(t *testing.T) { {`\\?\c:\long\foo.txt`, `\\?\c:\long\foo.txt`}, {`\\?\c:\long/foo.txt`, `\\?\c:\long/foo.txt`}, } { - in := strings.Replace(test.in, "long", veryLong, -1) - want := strings.Replace(test.want, "long", veryLong, -1) + in := strings.ReplaceAll(test.in, "long", veryLong) + want := strings.ReplaceAll(test.want, "long", veryLong) if got := os.FixLongPath(in); got != want { - got = strings.Replace(got, veryLong, "long", -1) + got = strings.ReplaceAll(got, veryLong, "long") t.Errorf("fixLongPath(%q) = %q; want %q", test.in, got, test.want) } } diff --git a/src/os/stat_test.go b/src/os/stat_test.go new file mode 100644 index 0000000000..d59edeb547 --- /dev/null +++ b/src/os/stat_test.go @@ -0,0 +1,276 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package os_test + +import ( + "internal/testenv" + "io/ioutil" + "os" + "path/filepath" + "runtime" + "testing" +) + +// testStatAndLstat verifies that all os.Stat, os.Lstat os.File.Stat and os.Readdir work. +func testStatAndLstat(t *testing.T, path string, isLink bool, statCheck, lstatCheck func(*testing.T, string, os.FileInfo)) { + // test os.Stat + sfi, err := os.Stat(path) + if err != nil { + t.Error(err) + return + } + statCheck(t, path, sfi) + + // test os.Lstat + lsfi, err := os.Lstat(path) + if err != nil { + t.Error(err) + return + } + lstatCheck(t, path, lsfi) + + if isLink { + if os.SameFile(sfi, lsfi) { + t.Errorf("stat and lstat of %q should not be the same", path) + } + } else { + if !os.SameFile(sfi, lsfi) { + t.Errorf("stat and lstat of %q should be the same", path) + } + } + + // test os.File.Stat + f, err := os.Open(path) + if err != nil { + t.Error(err) + return + } + defer f.Close() + + sfi2, err := f.Stat() + if err != nil { + t.Error(err) + return + } + statCheck(t, path, sfi2) + + if !os.SameFile(sfi, sfi2) { + t.Errorf("stat of open %q file and stat of %q should be the same", path, path) + } + + if isLink { + if os.SameFile(sfi2, lsfi) { + t.Errorf("stat of opened %q file and lstat of %q should not be the same", path, path) + } + } else { + if !os.SameFile(sfi2, lsfi) { + t.Errorf("stat of opened %q file and lstat of %q should be the same", path, path) + } + } + + // test os.FileInfo returned by os.Readdir + if len(path) > 0 && os.IsPathSeparator(path[len(path)-1]) { + // skip os.Readdir test of directories with slash at the end + return + } + parentdir := filepath.Dir(path) + parent, err := os.Open(parentdir) + if err != nil { + t.Error(err) + return + } + defer parent.Close() + + fis, err := parent.Readdir(-1) + if err != nil { + t.Error(err) + return + } + var lsfi2 os.FileInfo + base := filepath.Base(path) + for _, fi2 := range fis { + if fi2.Name() == base { + lsfi2 = fi2 + break + } + } + if lsfi2 == nil { + t.Errorf("failed to find %q in its parent", path) + return + } + lstatCheck(t, path, lsfi2) + + if !os.SameFile(lsfi, lsfi2) { + t.Errorf("lstat of %q file in %q directory and %q should be the same", lsfi2.Name(), parentdir, path) + } +} + +// testIsDir verifies that fi refers to directory. +func testIsDir(t *testing.T, path string, fi os.FileInfo) { + t.Helper() + if !fi.IsDir() { + t.Errorf("%q should be a directory", path) + } + if fi.Mode()&os.ModeSymlink != 0 { + t.Errorf("%q should not be a symlink", path) + } +} + +// testIsSymlink verifies that fi refers to symlink. +func testIsSymlink(t *testing.T, path string, fi os.FileInfo) { + t.Helper() + if fi.IsDir() { + t.Errorf("%q should not be a directory", path) + } + if fi.Mode()&os.ModeSymlink == 0 { + t.Errorf("%q should be a symlink", path) + } +} + +// testIsFile verifies that fi refers to file. +func testIsFile(t *testing.T, path string, fi os.FileInfo) { + t.Helper() + if fi.IsDir() { + t.Errorf("%q should not be a directory", path) + } + if fi.Mode()&os.ModeSymlink != 0 { + t.Errorf("%q should not be a symlink", path) + } +} + +func testDirStats(t *testing.T, path string) { + testStatAndLstat(t, path, false, testIsDir, testIsDir) +} + +func testFileStats(t *testing.T, path string) { + testStatAndLstat(t, path, false, testIsFile, testIsFile) +} + +func testSymlinkStats(t *testing.T, path string, isdir bool) { + if isdir { + testStatAndLstat(t, path, true, testIsDir, testIsSymlink) + } else { + testStatAndLstat(t, path, true, testIsFile, testIsSymlink) + } +} + +func testSymlinkSameFile(t *testing.T, path, link string) { + pathfi, err := os.Stat(path) + if err != nil { + t.Error(err) + return + } + + linkfi, err := os.Stat(link) + if err != nil { + t.Error(err) + return + } + if !os.SameFile(pathfi, linkfi) { + t.Errorf("os.Stat(%q) and os.Stat(%q) are not the same file", path, link) + } + + linkfi, err = os.Lstat(link) + if err != nil { + t.Error(err) + return + } + if os.SameFile(pathfi, linkfi) { + t.Errorf("os.Stat(%q) and os.Lstat(%q) are the same file", path, link) + } +} + +func TestDirAndSymlinkStats(t *testing.T) { + testenv.MustHaveSymlink(t) + + tmpdir, err := ioutil.TempDir("", "TestDirAndSymlinkStats") + if err != nil { + t.Fatal(err) + } + defer os.RemoveAll(tmpdir) + + dir := filepath.Join(tmpdir, "dir") + err = os.Mkdir(dir, 0777) + if err != nil { + t.Fatal(err) + } + testDirStats(t, dir) + + dirlink := filepath.Join(tmpdir, "link") + err = os.Symlink(dir, dirlink) + if err != nil { + t.Fatal(err) + } + testSymlinkStats(t, dirlink, true) + testSymlinkSameFile(t, dir, dirlink) +} + +func TestFileAndSymlinkStats(t *testing.T) { + testenv.MustHaveSymlink(t) + + tmpdir, err := ioutil.TempDir("", "TestFileAndSymlinkStats") + if err != nil { + t.Fatal(err) + } + defer os.RemoveAll(tmpdir) + + file := filepath.Join(tmpdir, "file") + err = ioutil.WriteFile(file, []byte(""), 0644) + if err != nil { + t.Fatal(err) + } + testFileStats(t, file) + + filelink := filepath.Join(tmpdir, "link") + err = os.Symlink(file, filelink) + if err != nil { + t.Fatal(err) + } + testSymlinkStats(t, filelink, false) + testSymlinkSameFile(t, file, filelink) +} + +// see issue 27225 for details +func TestSymlinkWithTrailingSlash(t *testing.T) { + if runtime.GOOS == "windows" { + t.Skip("skipping on windows; issue 27225") + } + + testenv.MustHaveSymlink(t) + + tmpdir, err := ioutil.TempDir("", "TestSymlinkWithTrailingSlash") + if err != nil { + t.Fatal(err) + } + defer os.RemoveAll(tmpdir) + + dir := filepath.Join(tmpdir, "dir") + err = os.Mkdir(dir, 0777) + if err != nil { + t.Fatal(err) + } + dirlink := filepath.Join(tmpdir, "link") + err = os.Symlink(dir, dirlink) + if err != nil { + t.Fatal(err) + } + dirlinkWithSlash := dirlink + string(os.PathSeparator) + + testDirStats(t, dirlinkWithSlash) + + fi1, err := os.Stat(dir) + if err != nil { + t.Error(err) + return + } + fi2, err := os.Stat(dirlinkWithSlash) + if err != nil { + t.Error(err) + return + } + if !os.SameFile(fi1, fi2) { + t.Errorf("os.Stat(%q) and os.Stat(%q) are not the same file", dir, dirlinkWithSlash) + } +} diff --git a/src/os/types.go b/src/os/types.go index b0b7d8d94d..4b6c084838 100644 --- a/src/os/types.go +++ b/src/os/types.go @@ -57,7 +57,7 @@ const ( ModeIrregular // ?: non-regular file; nothing else is known about this file // Mask for the type bits. For regular files, none will be set. - ModeType = ModeDir | ModeSymlink | ModeNamedPipe | ModeSocket | ModeDevice | ModeIrregular + ModeType = ModeDir | ModeSymlink | ModeNamedPipe | ModeSocket | ModeDevice | ModeCharDevice | ModeIrregular ModePerm FileMode = 0777 // Unix permission bits ) diff --git a/src/os/types_windows.go b/src/os/types_windows.go index f3297c0338..7ebeec50ef 100644 --- a/src/os/types_windows.go +++ b/src/os/types_windows.go @@ -211,7 +211,13 @@ func (fs *fileStat) loadFileId() error { if err != nil { return err } - h, err := syscall.CreateFile(pathp, 0, 0, nil, syscall.OPEN_EXISTING, syscall.FILE_FLAG_BACKUP_SEMANTICS, 0) + attrs := uint32(syscall.FILE_FLAG_BACKUP_SEMANTICS) + if fs.isSymlink() { + // Use FILE_FLAG_OPEN_REPARSE_POINT, otherwise CreateFile will follow symlink. + // See https://docs.microsoft.com/en-us/windows/desktop/FileIO/symbolic-link-effects-on-file-systems-functions#createfile-and-createfiletransacted + attrs |= syscall.FILE_FLAG_OPEN_REPARSE_POINT + } + h, err := syscall.CreateFile(pathp, 0, 0, nil, syscall.OPEN_EXISTING, attrs, 0) if err != nil { return err } diff --git a/src/os/user/lookup.go b/src/os/user/lookup.go index 2243a25788..b36b7c01c0 100644 --- a/src/os/user/lookup.go +++ b/src/os/user/lookup.go @@ -7,6 +7,10 @@ package user import "sync" // Current returns the current user. +// +// The first call will cache the current user information. +// Subsequent calls will return the cached value and will not reflect +// changes to the current user. func Current() (*User, error) { cache.Do(func() { cache.u, cache.err = current() }) if cache.err != nil { diff --git a/src/os/user/lookup_stubs.go b/src/os/user/lookup_stubs.go index f7d138ff46..9fc03c65d9 100644 --- a/src/os/user/lookup_stubs.go +++ b/src/os/user/lookup_stubs.go @@ -19,8 +19,15 @@ func init() { } func current() (*User, error) { - u := &User{ - Uid: currentUID(), + uid := currentUID() + // $USER and /etc/passwd may disagree; prefer the latter if we can get it. + // See issue 27524 for more information. + u, err := lookupUserId(uid) + if err == nil { + return u, nil + } + u = &User{ + Uid: uid, Gid: currentGID(), Username: os.Getenv("USER"), Name: "", // ignored diff --git a/src/os/user/user_test.go b/src/os/user/user_test.go index 8fd760e649..2563077eb2 100644 --- a/src/os/user/user_test.go +++ b/src/os/user/user_test.go @@ -5,33 +5,18 @@ package user import ( - "internal/testenv" - "os" "runtime" "testing" ) func checkUser(t *testing.T) { + t.Helper() if !userImplemented { t.Skip("user: not implemented; skipping tests") } } func TestCurrent(t *testing.T) { - // The Go builders (in particular the ones using containers) - // often have minimal environments without $HOME or $USER set, - // which breaks Current which relies on those working as a - // fallback. - // TODO: we should fix that (Issue 24884) and remove these - // workarounds. - if testenv.Builder() != "" && runtime.GOOS != "windows" && runtime.GOOS != "plan9" { - if os.Getenv("HOME") == "" { - os.Setenv("HOME", "/tmp") - } - if os.Getenv("USER") == "" { - os.Setenv("USER", "gobuilder") - } - } u, err := Current() if err != nil { t.Fatalf("Current: %v (got %#v)", err, u) @@ -108,6 +93,7 @@ func TestLookupId(t *testing.T) { } func checkGroup(t *testing.T) { + t.Helper() if !groupImplemented { t.Skip("user: group not implemented; skipping test") } diff --git a/src/path/filepath/path.go b/src/path/filepath/path.go index 1508137a33..bbb90306a7 100644 --- a/src/path/filepath/path.go +++ b/src/path/filepath/path.go @@ -96,14 +96,19 @@ func Clean(path string) string { } return originalPath + "." } + + n := len(path) + if volLen > 2 && n == 1 && os.IsPathSeparator(path[0]) { + // UNC volume name with trailing slash. + return FromSlash(originalPath[:volLen]) + } rooted := os.IsPathSeparator(path[0]) // Invariants: // reading from path; r is index of next byte to process. - // writing to buf; w is index of next byte to write. - // dotdot is index in buf where .. must stop, either because + // writing to out; w is index of next byte to write. + // dotdot is index in out where .. must stop, either because // it is the leading slash or it is a leading ../../.. prefix. - n := len(path) out := lazybuf{path: path, volAndPath: originalPath, volLen: volLen} r, dotdot := 0, 0 if rooted { @@ -166,7 +171,7 @@ func ToSlash(path string) string { if Separator == '/' { return path } - return strings.Replace(path, string(Separator), "/", -1) + return strings.ReplaceAll(path, string(Separator), "/") } // FromSlash returns the result of replacing each slash ('/') character @@ -176,7 +181,7 @@ func FromSlash(path string) string { if Separator == '/' { return path } - return strings.Replace(path, "/", string(Separator), -1) + return strings.ReplaceAll(path, "/", string(Separator)) } // SplitList splits a list of paths joined by the OS-specific ListSeparator, diff --git a/src/path/filepath/path_test.go b/src/path/filepath/path_test.go index e50ee97bcb..eddae4755b 100644 --- a/src/path/filepath/path_test.go +++ b/src/path/filepath/path_test.go @@ -92,6 +92,9 @@ var wincleantests = []PathTest{ {`//host/share/foo/../baz`, `\\host\share\baz`}, {`\\a\b\..\c`, `\\a\b\c`}, {`\\a\b`, `\\a\b`}, + {`\\a\b\`, `\\a\b`}, + {`\\folder\share\foo`, `\\folder\share\foo`}, + {`\\folder\share\foo\`, `\\folder\share\foo`}, } func TestClean(t *testing.T) { @@ -771,6 +774,18 @@ var EvalSymlinksTestDirs = []EvalSymlinksTest{ {"test/link1", "../test"}, {"test/link2", "dir"}, {"test/linkabs", "/"}, + {"test/link4", "../test2"}, + {"test2", "test/dir"}, + // Issue 23444. + {"src", ""}, + {"src/pool", ""}, + {"src/pool/test", ""}, + {"src/versions", ""}, + {"src/versions/current", "../../version"}, + {"src/versions/v1", ""}, + {"src/versions/v1/modules", ""}, + {"src/versions/v1/modules/test", "../../../pool/test"}, + {"version", "src/versions/v1"}, } var EvalSymlinksTests = []EvalSymlinksTest{ @@ -784,6 +799,8 @@ var EvalSymlinksTests = []EvalSymlinksTest{ {"test/dir/link3", "."}, {"test/link2/link3/test", "test"}, {"test/linkabs", "/"}, + {"test/link4/..", "test"}, + {"src/versions/current/modules/test", "src/pool/test"}, } // simpleJoin builds a file name from the directory and path. @@ -1048,7 +1065,7 @@ func TestAbs(t *testing.T) { } for _, path := range absTests { - path = strings.Replace(path, "$", root, -1) + path = strings.ReplaceAll(path, "$", root) info, err := os.Stat(path) if err != nil { t.Errorf("%s: %s", path, err) diff --git a/src/path/filepath/path_windows.go b/src/path/filepath/path_windows.go index 519b6ebc32..6a144d9e0b 100644 --- a/src/path/filepath/path_windows.go +++ b/src/path/filepath/path_windows.go @@ -100,7 +100,7 @@ func splitList(path string) []string { // Remove quotes. for i, s := range list { - list[i] = strings.Replace(s, `"`, ``, -1) + list[i] = strings.ReplaceAll(s, `"`, ``) } return list diff --git a/src/path/filepath/path_windows_test.go b/src/path/filepath/path_windows_test.go index e36a3c9b64..63eab18116 100644 --- a/src/path/filepath/path_windows_test.go +++ b/src/path/filepath/path_windows_test.go @@ -431,7 +431,7 @@ func TestToNorm(t *testing.T) { t.Fatal(err) } - err = os.MkdirAll(strings.Replace(testPath, "{{tmp}}", ctmp, -1), 0777) + err = os.MkdirAll(strings.ReplaceAll(testPath, "{{tmp}}", ctmp), 0777) if err != nil { t.Fatal(err) } diff --git a/src/path/filepath/symlink.go b/src/path/filepath/symlink.go index 824aee4e49..98a92357be 100644 --- a/src/path/filepath/symlink.go +++ b/src/path/filepath/symlink.go @@ -10,109 +10,126 @@ import ( "runtime" ) -// isRoot returns true if path is root of file system -// (`/` on unix and `/`, `\`, `c:\` or `c:/` on windows). -func isRoot(path string) bool { - if runtime.GOOS != "windows" { - return path == "/" - } - switch len(path) { - case 1: - return os.IsPathSeparator(path[0]) - case 3: - return path[1] == ':' && os.IsPathSeparator(path[2]) +func walkSymlinks(path string) (string, error) { + volLen := volumeNameLen(path) + if volLen < len(path) && os.IsPathSeparator(path[volLen]) { + volLen++ } - return false -} + vol := path[:volLen] + dest := vol + linksWalked := 0 + for start, end := volLen, volLen; start < len(path); start = end { + for start < len(path) && os.IsPathSeparator(path[start]) { + start++ + } + end = start + for end < len(path) && !os.IsPathSeparator(path[end]) { + end++ + } -// isDriveLetter returns true if path is Windows drive letter (like "c:"). -func isDriveLetter(path string) bool { - if runtime.GOOS != "windows" { - return false - } - return len(path) == 2 && path[1] == ':' -} + // On Windows, "." can be a symlink. + // We look it up, and use the value if it is absolute. + // If not, we just return ".". + isWindowsDot := runtime.GOOS == "windows" && path[volumeNameLen(path):] == "." -func walkLink(path string, linksWalked *int) (newpath string, islink bool, err error) { - if *linksWalked > 255 { - return "", false, errors.New("EvalSymlinks: too many links") - } - fi, err := os.Lstat(path) - if err != nil { - return "", false, err - } - if fi.Mode()&os.ModeSymlink == 0 { - return path, false, nil - } - newpath, err = os.Readlink(path) - if err != nil { - return "", false, err - } - *linksWalked++ - return newpath, true, nil -} - -func walkLinks(path string, linksWalked *int) (string, error) { - switch dir, file := Split(path); { - case dir == "": - newpath, _, err := walkLink(file, linksWalked) - return newpath, err - case file == "": - if isDriveLetter(dir) { - return dir, nil - } - if os.IsPathSeparator(dir[len(dir)-1]) { - if isRoot(dir) { - return dir, nil + // The next path component is in path[start:end]. + if end == start { + // No more path components. + break + } else if path[start:end] == "." && !isWindowsDot { + // Ignore path component ".". + continue + } else if path[start:end] == ".." { + // Back up to previous component if possible. + // Note that volLen includes any leading slash. + var r int + for r = len(dest) - 1; r >= volLen; r-- { + if os.IsPathSeparator(dest[r]) { + break + } + } + if r < volLen { + if len(dest) > volLen { + dest += string(os.PathSeparator) + } + dest += ".." + } else { + dest = dest[:r] } - return walkLinks(dir[:len(dir)-1], linksWalked) + continue } - newpath, _, err := walkLink(dir, linksWalked) - return newpath, err - default: - newdir, err := walkLinks(dir, linksWalked) - if err != nil { - return "", err + + // Ordinary path component. Add it to result. + + if len(dest) > volumeNameLen(dest) && !os.IsPathSeparator(dest[len(dest)-1]) { + dest += string(os.PathSeparator) } - newpath, islink, err := walkLink(Join(newdir, file), linksWalked) + + dest += path[start:end] + + // Resolve symlink. + + fi, err := os.Lstat(dest) if err != nil { return "", err } - if !islink { - return newpath, nil + + if fi.Mode()&os.ModeSymlink == 0 { + if !fi.Mode().IsDir() && end < len(path) { + return "", os.ErrNotExist + } + continue } - if IsAbs(newpath) || os.IsPathSeparator(newpath[0]) { - return newpath, nil + + // Found symlink. + + linksWalked++ + if linksWalked > 255 { + return "", errors.New("EvalSymlinks: too many links") } - return Join(newdir, newpath), nil - } -} -func walkSymlinks(path string) (string, error) { - if path == "" { - return path, nil - } - var linksWalked int // to protect against cycles - for { - i := linksWalked - newpath, err := walkLinks(path, &linksWalked) + link, err := os.Readlink(dest) if err != nil { return "", err } - if runtime.GOOS == "windows" { - // walkLinks(".", ...) always returns "." on unix. - // But on windows it returns symlink target, if current - // directory is a symlink. Stop the walk, if symlink - // target is not absolute path, and return "." - // to the caller (just like unix does). - // Same for "C:.". - if path[volumeNameLen(path):] == "." && !IsAbs(newpath) { - return path, nil - } + + if isWindowsDot && !IsAbs(link) { + // On Windows, if "." is a relative symlink, + // just return ".". + break } - if i == linksWalked { - return Clean(newpath), nil + + path = link + path[end:] + + v := volumeNameLen(link) + if v > 0 { + // Symlink to drive name is an absolute path. + if v < len(link) && os.IsPathSeparator(link[v]) { + v++ + } + vol = link[:v] + dest = vol + end = len(vol) + } else if len(link) > 0 && os.IsPathSeparator(link[0]) { + // Symlink to absolute path. + dest = link[:1] + end = 1 + } else { + // Symlink to relative path; replace last + // path component in dest. + var r int + for r = len(dest) - 1; r >= volLen; r-- { + if os.IsPathSeparator(dest[r]) { + break + } + } + if r < volLen { + dest = vol + } else { + dest = dest[:r] + } + end = 0 } - path = newpath } + return Clean(dest), nil } diff --git a/src/reflect/all_test.go b/src/reflect/all_test.go index c616b37008..c463b61c57 100644 --- a/src/reflect/all_test.go +++ b/src/reflect/all_test.go @@ -5844,7 +5844,7 @@ func clobber() { type funcLayoutTest struct { rcvr, t Type size, argsize, retOffset uintptr - stack []byte // pointer bitmap: 1 is pointer, 0 is scalar (or uninitialized) + stack []byte // pointer bitmap: 1 is pointer, 0 is scalar gc []byte } @@ -5866,7 +5866,7 @@ func init() { 6 * PtrSize, 4 * PtrSize, 4 * PtrSize, - []byte{1, 0, 1}, + []byte{1, 0, 1, 0, 1}, []byte{1, 0, 1, 0, 1}, }) @@ -5988,7 +5988,8 @@ func TestFuncLayout(t *testing.T) { func verifyGCBits(t *testing.T, typ Type, bits []byte) { heapBits := GCBits(New(typ).Interface()) if !bytes.Equal(heapBits, bits) { - t.Errorf("heapBits incorrect for %v\nhave %v\nwant %v", typ, heapBits, bits) + _, _, line, _ := runtime.Caller(1) + t.Errorf("line %d: heapBits incorrect for %v\nhave %v\nwant %v", line, typ, heapBits, bits) } } diff --git a/src/reflect/asm_386.s b/src/reflect/asm_386.s index d827360006..e79beb6dc9 100644 --- a/src/reflect/asm_386.s +++ b/src/reflect/asm_386.s @@ -9,11 +9,14 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No argsize here, gc generates argsize info at call site. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$8 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 NO_LOCAL_POINTERS MOVL DX, 0(SP) LEAL argframe+0(FP), CX MOVL CX, 4(SP) + MOVB $0, 12(SP) + LEAL 12(SP), AX + MOVL AX, 8(SP) CALL ·callReflect(SB) RET @@ -21,10 +24,13 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$8 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No argsize here, gc generates argsize info at call site. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$8 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 NO_LOCAL_POINTERS MOVL DX, 0(SP) LEAL argframe+0(FP), CX MOVL CX, 4(SP) + MOVB $0, 12(SP) + LEAL 12(SP), AX + MOVL AX, 8(SP) CALL ·callMethod(SB) RET diff --git a/src/reflect/asm_amd64.s b/src/reflect/asm_amd64.s index 1272c489de..fb28ab87f1 100644 --- a/src/reflect/asm_amd64.s +++ b/src/reflect/asm_amd64.s @@ -9,11 +9,14 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVQ DX, 0(SP) LEAQ argframe+0(FP), CX MOVQ CX, 8(SP) + MOVB $0, 24(SP) + LEAQ 24(SP), AX + MOVQ AX, 16(SP) CALL ·callReflect(SB) RET @@ -21,10 +24,13 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVQ DX, 0(SP) LEAQ argframe+0(FP), CX MOVQ CX, 8(SP) + MOVB $0, 24(SP) + LEAQ 24(SP), AX + MOVQ AX, 16(SP) CALL ·callMethod(SB) RET diff --git a/src/reflect/asm_amd64p32.s b/src/reflect/asm_amd64p32.s index d827360006..e79beb6dc9 100644 --- a/src/reflect/asm_amd64p32.s +++ b/src/reflect/asm_amd64p32.s @@ -9,11 +9,14 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No argsize here, gc generates argsize info at call site. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$8 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 NO_LOCAL_POINTERS MOVL DX, 0(SP) LEAL argframe+0(FP), CX MOVL CX, 4(SP) + MOVB $0, 12(SP) + LEAL 12(SP), AX + MOVL AX, 8(SP) CALL ·callReflect(SB) RET @@ -21,10 +24,13 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$8 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No argsize here, gc generates argsize info at call site. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$8 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 NO_LOCAL_POINTERS MOVL DX, 0(SP) LEAL argframe+0(FP), CX MOVL CX, 4(SP) + MOVB $0, 12(SP) + LEAL 12(SP), AX + MOVL AX, 8(SP) CALL ·callMethod(SB) RET diff --git a/src/reflect/asm_arm.s b/src/reflect/asm_arm.s index b721ed28c6..cd50d33918 100644 --- a/src/reflect/asm_arm.s +++ b/src/reflect/asm_arm.s @@ -9,11 +9,15 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No argsize here, gc generates argsize info at call site. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$8 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 NO_LOCAL_POINTERS MOVW R7, 4(R13) MOVW $argframe+0(FP), R1 MOVW R1, 8(R13) + MOVW $0, R1 + MOVB R1, 16(R13) + ADD $16, R13, R1 + MOVW R1, 12(R13) BL ·callReflect(SB) RET @@ -21,10 +25,14 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$8 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No argsize here, gc generates argsize info at call site. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$8 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 NO_LOCAL_POINTERS MOVW R7, 4(R13) MOVW $argframe+0(FP), R1 MOVW R1, 8(R13) + MOVW $0, R1 + MOVB R1, 16(R13) + ADD $16, R13, R1 + MOVW R1, 12(R13) BL ·callMethod(SB) RET diff --git a/src/reflect/asm_arm64.s b/src/reflect/asm_arm64.s index d1563709f2..28bb86c2a4 100644 --- a/src/reflect/asm_arm64.s +++ b/src/reflect/asm_arm64.s @@ -9,11 +9,14 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No arg size here, runtime pulls arg map out of the func value. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$24 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$40 NO_LOCAL_POINTERS MOVD R26, 8(RSP) MOVD $argframe+0(FP), R3 MOVD R3, 16(RSP) + MOVB $0, 32(RSP) + ADD $32, RSP, R3 + MOVD R3, 24(RSP) BL ·callReflect(SB) RET @@ -21,10 +24,13 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$24 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$24 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$40 NO_LOCAL_POINTERS MOVD R26, 8(RSP) MOVD $argframe+0(FP), R3 MOVD R3, 16(RSP) + MOVB $0, 32(RSP) + ADD $32, RSP, R3 + MOVD R3, 24(RSP) BL ·callMethod(SB) RET diff --git a/src/reflect/asm_mips64x.s b/src/reflect/asm_mips64x.s index 98afb52f6a..6f76685567 100644 --- a/src/reflect/asm_mips64x.s +++ b/src/reflect/asm_mips64x.s @@ -13,11 +13,14 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No arg size here, runtime pulls arg map out of the func value. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVV REGCTXT, 8(R29) MOVV $argframe+0(FP), R1 MOVV R1, 16(R29) + MOVB R0, 32(R29) + ADDV $32, R29, R1 + MOVV R1, 24(R29) JAL ·callReflect(SB) RET @@ -25,10 +28,13 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVV REGCTXT, 8(R29) MOVV $argframe+0(FP), R1 MOVV R1, 16(R29) + MOVB R0, 32(R29) + ADDV $32, R29, R1 + MOVV R1, 24(R29) JAL ·callMethod(SB) RET diff --git a/src/reflect/asm_mipsx.s b/src/reflect/asm_mipsx.s index b6df4e636e..5a5c53ef9f 100644 --- a/src/reflect/asm_mipsx.s +++ b/src/reflect/asm_mipsx.s @@ -13,11 +13,14 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No arg size here, runtime pulls arg map out of the func value. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$8 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 NO_LOCAL_POINTERS MOVW REGCTXT, 4(R29) MOVW $argframe+0(FP), R1 MOVW R1, 8(R29) + MOVB R0, 16(R29) + ADD $16, R29, R1 + MOVW R1, 12(R29) JAL ·callReflect(SB) RET @@ -25,10 +28,13 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$8 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$8 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 NO_LOCAL_POINTERS MOVW REGCTXT, 4(R29) MOVW $argframe+0(FP), R1 MOVW R1, 8(R29) + MOVB R0, 16(R29) + ADD $16, R29, R1 + MOVW R1, 12(R29) JAL ·callMethod(SB) RET diff --git a/src/reflect/asm_ppc64x.s b/src/reflect/asm_ppc64x.s index 42f57743e6..4609f6bb75 100644 --- a/src/reflect/asm_ppc64x.s +++ b/src/reflect/asm_ppc64x.s @@ -12,11 +12,14 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No arg size here, runtime pulls arg map out of the func value. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVD R11, FIXED_FRAME+0(R1) MOVD $argframe+0(FP), R3 MOVD R3, FIXED_FRAME+8(R1) + MOVB R0, FIXED_FRAME+24(R1) + ADD $FIXED_FRAME+24, R1, R3 + MOVD R3, FIXED_FRAME+16(R1) BL ·callReflect(SB) RET @@ -24,10 +27,13 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVD R11, FIXED_FRAME+0(R1) MOVD $argframe+0(FP), R3 MOVD R3, FIXED_FRAME+8(R1) + MOVB R0, FIXED_FRAME+24(R1) + ADD $FIXED_FRAME+24, R1, R3 + MOVD R3, FIXED_FRAME+16(R1) BL ·callMethod(SB) RET diff --git a/src/reflect/asm_s390x.s b/src/reflect/asm_s390x.s index e6b86cfaa9..cb7954c900 100644 --- a/src/reflect/asm_s390x.s +++ b/src/reflect/asm_s390x.s @@ -9,11 +9,14 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No arg size here, runtime pulls arg map out of the func value. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVD R12, 8(R15) MOVD $argframe+0(FP), R3 MOVD R3, 16(R15) + MOVB $0, 32(R15) + ADD $32, R15, R3 + MOVD R3, 24(R15) BL ·callReflect(SB) RET @@ -21,10 +24,13 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVD R12, 8(R15) MOVD $argframe+0(FP), R3 MOVD R3, 16(R15) + MOVB $0, 32(R15) + ADD $32, R15, R3 + MOVD R3, 24(R15) BL ·callMethod(SB) RET diff --git a/src/reflect/asm_wasm.s b/src/reflect/asm_wasm.s index 0f9b5aa130..627e295769 100644 --- a/src/reflect/asm_wasm.s +++ b/src/reflect/asm_wasm.s @@ -9,7 +9,7 @@ // See the comment on the declaration of makeFuncStub in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVD CTXT, 0(SP) @@ -21,6 +21,9 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 I64Add I64Store $8 + MOVB $0, 24(SP) + MOVD $24(SP), 16(SP) + CALL ·callReflect(SB) RET @@ -28,7 +31,7 @@ TEXT ·makeFuncStub(SB),(NOSPLIT|WRAPPER),$16 // See the comment on the declaration of methodValueCall in makefunc.go // for more details. // No arg size here; runtime pulls arg map out of the func value. -TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 +TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$32 NO_LOCAL_POINTERS MOVD CTXT, 0(SP) @@ -40,5 +43,8 @@ TEXT ·methodValueCall(SB),(NOSPLIT|WRAPPER),$16 I64Add I64Store $8 + MOVB $0, 24(SP) + MOVD $24(SP), 16(SP) + CALL ·callMethod(SB) RET diff --git a/src/reflect/example_test.go b/src/reflect/example_test.go index f959b95846..23c08e4950 100644 --- a/src/reflect/example_test.go +++ b/src/reflect/example_test.go @@ -13,6 +13,24 @@ import ( "reflect" ) +func ExampleKind() { + for _, v := range []interface{}{"hi", 42, func() {}} { + switch v := reflect.ValueOf(v); v.Kind() { + case reflect.String: + fmt.Println(v.String()) + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + fmt.Println(v.Int()) + default: + fmt.Printf("unhandled kind %s", v.Kind()) + } + } + + // Output: + // hi + // 42 + // unhandled kind func +} + func ExampleMakeFunc() { // swap is the implementation passed to MakeFunc. // It must work in terms of reflect.Values so that it is possible diff --git a/src/reflect/export_test.go b/src/reflect/export_test.go index 14a6981fde..3c47d6712f 100644 --- a/src/reflect/export_test.go +++ b/src/reflect/export_test.go @@ -25,9 +25,9 @@ func FuncLayout(t Type, rcvr Type) (frametype Type, argSize, retOffset uintptr, var ft *rtype var s *bitVector if rcvr != nil { - ft, argSize, retOffset, s, _ = funcLayout(t.(*rtype), rcvr.(*rtype)) + ft, argSize, retOffset, s, _ = funcLayout((*funcType)(unsafe.Pointer(t.(*rtype))), rcvr.(*rtype)) } else { - ft, argSize, retOffset, s, _ = funcLayout(t.(*rtype), nil) + ft, argSize, retOffset, s, _ = funcLayout((*funcType)(unsafe.Pointer(t.(*rtype))), nil) } frametype = ft for i := uint32(0); i < s.n; i++ { diff --git a/src/reflect/makefunc.go b/src/reflect/makefunc.go index 885966db6f..67dc4859b9 100644 --- a/src/reflect/makefunc.go +++ b/src/reflect/makefunc.go @@ -12,14 +12,15 @@ import ( // makeFuncImpl is the closure value implementing the function // returned by MakeFunc. -// The first two words of this type must be kept in sync with +// The first three words of this type must be kept in sync with // methodValue and runtime.reflectMethodValue. // Any changes should be reflected in all three. type makeFuncImpl struct { - code uintptr - stack *bitVector - typ *funcType - fn func([]Value) []Value + code uintptr + stack *bitVector // ptrmap for both args and results + argLen uintptr // just args + ftyp *funcType + fn func([]Value) []Value } // MakeFunc returns a new function of the given Type @@ -59,9 +60,9 @@ func MakeFunc(typ Type, fn func(args []Value) (results []Value)) Value { code := **(**uintptr)(unsafe.Pointer(&dummy)) // makeFuncImpl contains a stack map for use by the runtime - _, _, _, stack, _ := funcLayout(t, nil) + _, argLen, _, stack, _ := funcLayout(ftyp, nil) - impl := &makeFuncImpl{code: code, stack: stack, typ: ftyp, fn: fn} + impl := &makeFuncImpl{code: code, stack: stack, argLen: argLen, ftyp: ftyp, fn: fn} return Value{t, unsafe.Pointer(impl), flag(Func)} } @@ -73,12 +74,13 @@ func MakeFunc(typ Type, fn func(args []Value) (results []Value)) Value { // word in the passed-in argument frame. func makeFuncStub() -// The first two words of this type must be kept in sync with +// The first 3 words of this type must be kept in sync with // makeFuncImpl and runtime.reflectMethodValue. // Any changes should be reflected in all three. type methodValue struct { fn uintptr - stack *bitVector + stack *bitVector // ptrmap for both args and results + argLen uintptr // just args method int rcvr Value } @@ -101,7 +103,7 @@ func makeMethodValue(op string, v Value) Value { rcvr := Value{v.typ, v.ptr, fl} // v.Type returns the actual type of the method value. - funcType := v.Type().(*rtype) + ftyp := (*funcType)(unsafe.Pointer(v.Type().(*rtype))) // Indirect Go func value (dummy) to obtain // actual code address. (A Go func value is a pointer @@ -110,11 +112,12 @@ func makeMethodValue(op string, v Value) Value { code := **(**uintptr)(unsafe.Pointer(&dummy)) // methodValue contains a stack map for use by the runtime - _, _, _, stack, _ := funcLayout(funcType, nil) + _, argLen, _, stack, _ := funcLayout(ftyp, nil) fv := &methodValue{ fn: code, stack: stack, + argLen: argLen, method: int(v.flag) >> flagMethodShift, rcvr: rcvr, } @@ -124,7 +127,7 @@ func makeMethodValue(op string, v Value) Value { // but we want Interface() and other operations to fail early. methodReceiver(op, fv.rcvr, fv.method) - return Value{funcType, unsafe.Pointer(fv), v.flag&flagRO | flag(Func)} + return Value{&ftyp.rtype, unsafe.Pointer(fv), v.flag&flagRO | flag(Func)} } // methodValueCall is an assembly function that is the code half of diff --git a/src/reflect/type.go b/src/reflect/type.go index 58cfc0e884..d8971d620e 100644 --- a/src/reflect/type.go +++ b/src/reflect/type.go @@ -3022,8 +3022,8 @@ func toType(t *rtype) Type { } type layoutKey struct { - t *rtype // function signature - rcvr *rtype // receiver type, or nil if none + ftyp *funcType // function signature + rcvr *rtype // receiver type, or nil if none } type layoutType struct { @@ -3042,7 +3042,7 @@ var layoutCache sync.Map // map[layoutKey]layoutType // The returned type exists only for GC, so we only fill out GC relevant info. // Currently, that's just size and the GC program. We also fill in // the name for possible debugging use. -func funcLayout(t *rtype, rcvr *rtype) (frametype *rtype, argSize, retOffset uintptr, stk *bitVector, framePool *sync.Pool) { +func funcLayout(t *funcType, rcvr *rtype) (frametype *rtype, argSize, retOffset uintptr, stk *bitVector, framePool *sync.Pool) { if t.Kind() != Func { panic("reflect: funcLayout of non-func type") } @@ -3055,8 +3055,6 @@ func funcLayout(t *rtype, rcvr *rtype) (frametype *rtype, argSize, retOffset uin return lt.t, lt.argSize, lt.retOffset, lt.stack, lt.framePool } - tt := (*funcType)(unsafe.Pointer(t)) - // compute gc program & stack bitmap for arguments ptrmap := new(bitVector) var offset uintptr @@ -3066,22 +3064,23 @@ func funcLayout(t *rtype, rcvr *rtype) (frametype *rtype, argSize, retOffset uin // space no matter how big they actually are. if ifaceIndir(rcvr) || rcvr.pointers() { ptrmap.append(1) + } else { + ptrmap.append(0) } offset += ptrSize } - for _, arg := range tt.in() { + for _, arg := range t.in() { offset += -offset & uintptr(arg.align-1) addTypeBits(ptrmap, offset, arg) offset += arg.size } - argN := ptrmap.n argSize = offset if runtime.GOARCH == "amd64p32" { offset += -offset & (8 - 1) } offset += -offset & (ptrSize - 1) retOffset = offset - for _, res := range tt.out() { + for _, res := range t.out() { offset += -offset & uintptr(res.align-1) addTypeBits(ptrmap, offset, res) offset += res.size @@ -3102,7 +3101,6 @@ func funcLayout(t *rtype, rcvr *rtype) (frametype *rtype, argSize, retOffset uin } else { x.kind |= kindNoPointers } - ptrmap.n = argN var s string if rcvr != nil { diff --git a/src/reflect/value.go b/src/reflect/value.go index 1c3e590377..6d2862dbab 100644 --- a/src/reflect/value.go +++ b/src/reflect/value.go @@ -325,7 +325,7 @@ var callGC bool // for testing; see TestCallMethodJump func (v Value) call(op string, in []Value) []Value { // Get function pointer, type. - t := v.typ + t := (*funcType)(unsafe.Pointer(v.typ)) var ( fn unsafe.Pointer rcvr Value @@ -453,15 +453,14 @@ func (v Value) call(op string, in []Value) []Value { var ret []Value if nout == 0 { - // This is untyped because the frame is really a - // stack, even though it's a heap object. - memclrNoHeapPointers(args, frametype.size) + typedmemclr(frametype, args) framePool.Put(args) } else { // Zero the now unused input area of args, // because the Values returned by this function contain pointers to the args object, // and will thus keep the args object alive indefinitely. - memclrNoHeapPointers(args, retOffset) + typedmemclrpartial(frametype, args, 0, retOffset) + // Wrap Values around return values in args. ret = make([]Value, nout) off = retOffset @@ -472,6 +471,10 @@ func (v Value) call(op string, in []Value) []Value { if tv.Size() != 0 { fl := flagIndir | flag(tv.Kind()) ret[i] = Value{tv.common(), add(args, off, "tv.Size() != 0"), fl} + // Note: this does introduce false sharing between results - + // if any result is live, they are all live. + // (And the space for the args is live as well, but as we've + // cleared that space it isn't as big a deal.) } else { // For zero-sized return value, args+off may point to the next object. // In this case, return the zero value instead. @@ -496,8 +499,13 @@ func (v Value) call(op string, in []Value) []Value { // NOTE: This function must be marked as a "wrapper" in the generated code, // so that the linker can make it work correctly for panic and recover. // The gc compilers know to do that for the name "reflect.callReflect". -func callReflect(ctxt *makeFuncImpl, frame unsafe.Pointer) { - ftyp := ctxt.typ +// +// ctxt is the "closure" generated by MakeFunc. +// frame is a pointer to the arguments to that closure on the stack. +// retValid points to a boolean which should be set when the results +// section of frame is set. +func callReflect(ctxt *makeFuncImpl, frame unsafe.Pointer, retValid *bool) { + ftyp := ctxt.ftyp f := ctxt.fn // Copy argument frame into Values. @@ -562,6 +570,16 @@ func callReflect(ctxt *makeFuncImpl, frame unsafe.Pointer) { } } + // Announce that the return values are valid. + // After this point the runtime can depend on the return values being valid. + *retValid = true + + // We have to make sure that the out slice lives at least until + // the runtime knows the return values are valid. Otherwise, the + // return values might not be scanned by anyone during a GC. + // (out would be dead, and the return slots not yet alive.) + runtime.KeepAlive(out) + // runtime.getArgInfo expects to be able to find ctxt on the // stack when it finds our caller, makeFuncStub. Make sure it // doesn't get garbage collected. @@ -575,7 +593,7 @@ func callReflect(ctxt *makeFuncImpl, frame unsafe.Pointer) { // The return value rcvrtype gives the method's actual receiver type. // The return value t gives the method type signature (without the receiver). // The return value fn is a pointer to the method code. -func methodReceiver(op string, v Value, methodIndex int) (rcvrtype, t *rtype, fn unsafe.Pointer) { +func methodReceiver(op string, v Value, methodIndex int) (rcvrtype *rtype, t *funcType, fn unsafe.Pointer) { i := methodIndex if v.typ.Kind() == Interface { tt := (*interfaceType)(unsafe.Pointer(v.typ)) @@ -592,7 +610,7 @@ func methodReceiver(op string, v Value, methodIndex int) (rcvrtype, t *rtype, fn } rcvrtype = iface.itab.typ fn = unsafe.Pointer(&iface.itab.fun[i]) - t = tt.typeOff(m.typ) + t = (*funcType)(unsafe.Pointer(tt.typeOff(m.typ))) } else { rcvrtype = v.typ ms := v.typ.exportedMethods() @@ -605,7 +623,7 @@ func methodReceiver(op string, v Value, methodIndex int) (rcvrtype, t *rtype, fn } ifn := v.typ.textOff(m.ifn) fn = unsafe.Pointer(&ifn) - t = v.typ.typeOff(m.mtyp) + t = (*funcType)(unsafe.Pointer(v.typ.typeOff(m.mtyp))) } return } @@ -644,23 +662,31 @@ func align(x, n uintptr) uintptr { // NOTE: This function must be marked as a "wrapper" in the generated code, // so that the linker can make it work correctly for panic and recover. // The gc compilers know to do that for the name "reflect.callMethod". -func callMethod(ctxt *methodValue, frame unsafe.Pointer) { +// +// ctxt is the "closure" generated by makeVethodValue. +// frame is a pointer to the arguments to that closure on the stack. +// retValid points to a boolean which should be set when the results +// section of frame is set. +func callMethod(ctxt *methodValue, frame unsafe.Pointer, retValid *bool) { rcvr := ctxt.rcvr rcvrtype, t, fn := methodReceiver("call", rcvr, ctxt.method) frametype, argSize, retOffset, _, framePool := funcLayout(t, rcvrtype) // Make a new frame that is one word bigger so we can store the receiver. - args := framePool.Get().(unsafe.Pointer) + // This space is used for both arguments and return values. + scratch := framePool.Get().(unsafe.Pointer) // Copy in receiver and rest of args. // Avoid constructing out-of-bounds pointers if there are no args. - storeRcvr(rcvr, args) + storeRcvr(rcvr, scratch) if argSize-ptrSize > 0 { - typedmemmovepartial(frametype, add(args, ptrSize, "argSize > ptrSize"), frame, ptrSize, argSize-ptrSize) + typedmemmovepartial(frametype, add(scratch, ptrSize, "argSize > ptrSize"), frame, ptrSize, argSize-ptrSize) } // Call. - call(frametype, fn, args, uint32(frametype.size), uint32(retOffset)) + // Call copies the arguments from scratch to the stack, calls fn, + // and then copies the results back into scratch. + call(frametype, fn, scratch, uint32(frametype.size), uint32(retOffset)) // Copy return values. On amd64p32, the beginning of return values // is 64-bit aligned, so the caller's frame layout (which doesn't have @@ -673,17 +699,21 @@ func callMethod(ctxt *methodValue, frame unsafe.Pointer) { if runtime.GOARCH == "amd64p32" { callerRetOffset = align(argSize-ptrSize, 8) } - typedmemmovepartial(frametype, - add(frame, callerRetOffset, "frametype.size > retOffset"), - add(args, retOffset, "frametype.size > retOffset"), - retOffset, + // This copies to the stack. Write barriers are not needed. + memmove(add(frame, callerRetOffset, "frametype.size > retOffset"), + add(scratch, retOffset, "frametype.size > retOffset"), frametype.size-retOffset) } - // This is untyped because the frame is really a stack, even - // though it's a heap object. - memclrNoHeapPointers(args, frametype.size) - framePool.Put(args) + // Tell the runtime it can now depend on the return values + // being properly initialized. + *retValid = true + + // Clear the scratch space and put it back in the pool. + // This must happen after the statement above, so that the return + // values will always be scanned by someone. + typedmemclr(frametype, scratch) + framePool.Put(scratch) // See the comment in callReflect. runtime.KeepAlive(ctxt) @@ -2641,6 +2671,10 @@ func call(argtype *rtype, fn, arg unsafe.Pointer, n uint32, retoffset uint32) func ifaceE2I(t *rtype, src interface{}, dst unsafe.Pointer) +// memmove copies size bytes to dst from src. No write barriers are used. +//go:noescape +func memmove(dst, src unsafe.Pointer, size uintptr) + // typedmemmove copies a value of type t to dst from src. //go:noescape func typedmemmove(t *rtype, dst, src unsafe.Pointer) @@ -2650,14 +2684,20 @@ func typedmemmove(t *rtype, dst, src unsafe.Pointer) //go:noescape func typedmemmovepartial(t *rtype, dst, src unsafe.Pointer, off, size uintptr) +// typedmemclr zeros the value at ptr of type t. +//go:noescape +func typedmemclr(t *rtype, ptr unsafe.Pointer) + +// typedmemclrpartial is like typedmemclr but assumes that +// dst points off bytes into the value and only clears size bytes. +//go:noescape +func typedmemclrpartial(t *rtype, ptr unsafe.Pointer, off, size uintptr) + // typedslicecopy copies a slice of elemType values from src to dst, // returning the number of elements copied. //go:noescape func typedslicecopy(elemType *rtype, dst, src sliceHeader) int -//go:noescape -func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr) - // Dummy annotation marking that the value x escapes, // for use in cases where the reflect code is so clever that // the compiler cannot follow. diff --git a/src/regexp/regexp.go b/src/regexp/regexp.go index 61ed9c5059..89bb975ac1 100644 --- a/src/regexp/regexp.go +++ b/src/regexp/regexp.go @@ -469,7 +469,7 @@ func MatchString(pattern string, s string) (matched bool, err error) { return re.MatchString(s), nil } -// MatchString reports whether the byte slice b +// Match reports whether the byte slice b // contains any match of the regular expression pattern. // More complicated queries need to use Compile and the full Regexp interface. func Match(pattern string, b []byte) (matched bool, err error) { diff --git a/src/runtime/asm_386.s b/src/runtime/asm_386.s index 7761415ecd..5bc2063bed 100644 --- a/src/runtime/asm_386.s +++ b/src/runtime/asm_386.s @@ -107,7 +107,7 @@ TEXT runtime·rt0_go(SB),NOSPLIT,$0 MOVL BX, g_stackguard1(BP) MOVL BX, (g_stack+stack_lo)(BP) MOVL SP, (g_stack+stack_hi)(BP) - + // find out information about the processor we're on #ifdef GOOS_nacl // NaCl doesn't like PUSHFL/POPFL JMP has_cpuid @@ -827,7 +827,7 @@ havem: MOVL (g_sched+gobuf_sp)(SI), SP MOVL 0(SP), AX MOVL AX, (g_sched+gobuf_sp)(SI) - + // If the m on entry was nil, we called needm above to borrow an m // for the duration of the call. Since the call is over, return it with dropm. CMPL DX, $0 @@ -942,7 +942,7 @@ TEXT runtime·aeshashbody(SB),NOSPLIT,$0-0 CMPL BX, $64 JBE aes33to64 JMP aes65plus - + aes0to15: TESTL BX, BX JE aes0 @@ -957,7 +957,7 @@ aes0to15: ADDL BX, BX PAND masks<>(SB)(BX*8), X1 -final1: +final1: AESENC X0, X1 // scramble input, xor in seed AESENC X1, X1 // scramble combo 2 times AESENC X1, X1 @@ -987,7 +987,7 @@ aes17to32: // make second starting seed PXOR runtime·aeskeysched+16(SB), X1 AESENC X1, X1 - + // load data to be hashed MOVOU (AX), X2 MOVOU -16(AX)(BX*1), X3 @@ -1015,22 +1015,22 @@ aes33to64: AESENC X1, X1 AESENC X2, X2 AESENC X3, X3 - + MOVOU (AX), X4 MOVOU 16(AX), X5 MOVOU -32(AX)(BX*1), X6 MOVOU -16(AX)(BX*1), X7 - + AESENC X0, X4 AESENC X1, X5 AESENC X2, X6 AESENC X3, X7 - + AESENC X4, X4 AESENC X5, X5 AESENC X6, X6 AESENC X7, X7 - + AESENC X4, X4 AESENC X5, X5 AESENC X6, X6 @@ -1052,7 +1052,7 @@ aes65plus: AESENC X1, X1 AESENC X2, X2 AESENC X3, X3 - + // start with last (possibly overlapping) block MOVOU -64(AX)(BX*1), X4 MOVOU -48(AX)(BX*1), X5 @@ -1068,7 +1068,7 @@ aes65plus: // compute number of remaining 64-byte blocks DECL BX SHRL $6, BX - + aesloop: // scramble state, xor in a block MOVOU (AX), X0 @@ -1095,7 +1095,7 @@ aesloop: AESENC X5, X5 AESENC X6, X6 AESENC X7, X7 - + AESENC X4, X4 AESENC X5, X5 AESENC X6, X6 @@ -1132,77 +1132,77 @@ DATA masks<>+0x00(SB)/4, $0x00000000 DATA masks<>+0x04(SB)/4, $0x00000000 DATA masks<>+0x08(SB)/4, $0x00000000 DATA masks<>+0x0c(SB)/4, $0x00000000 - + DATA masks<>+0x10(SB)/4, $0x000000ff DATA masks<>+0x14(SB)/4, $0x00000000 DATA masks<>+0x18(SB)/4, $0x00000000 DATA masks<>+0x1c(SB)/4, $0x00000000 - + DATA masks<>+0x20(SB)/4, $0x0000ffff DATA masks<>+0x24(SB)/4, $0x00000000 DATA masks<>+0x28(SB)/4, $0x00000000 DATA masks<>+0x2c(SB)/4, $0x00000000 - + DATA masks<>+0x30(SB)/4, $0x00ffffff DATA masks<>+0x34(SB)/4, $0x00000000 DATA masks<>+0x38(SB)/4, $0x00000000 DATA masks<>+0x3c(SB)/4, $0x00000000 - + DATA masks<>+0x40(SB)/4, $0xffffffff DATA masks<>+0x44(SB)/4, $0x00000000 DATA masks<>+0x48(SB)/4, $0x00000000 DATA masks<>+0x4c(SB)/4, $0x00000000 - + DATA masks<>+0x50(SB)/4, $0xffffffff DATA masks<>+0x54(SB)/4, $0x000000ff DATA masks<>+0x58(SB)/4, $0x00000000 DATA masks<>+0x5c(SB)/4, $0x00000000 - + DATA masks<>+0x60(SB)/4, $0xffffffff DATA masks<>+0x64(SB)/4, $0x0000ffff DATA masks<>+0x68(SB)/4, $0x00000000 DATA masks<>+0x6c(SB)/4, $0x00000000 - + DATA masks<>+0x70(SB)/4, $0xffffffff DATA masks<>+0x74(SB)/4, $0x00ffffff DATA masks<>+0x78(SB)/4, $0x00000000 DATA masks<>+0x7c(SB)/4, $0x00000000 - + DATA masks<>+0x80(SB)/4, $0xffffffff DATA masks<>+0x84(SB)/4, $0xffffffff DATA masks<>+0x88(SB)/4, $0x00000000 DATA masks<>+0x8c(SB)/4, $0x00000000 - + DATA masks<>+0x90(SB)/4, $0xffffffff DATA masks<>+0x94(SB)/4, $0xffffffff DATA masks<>+0x98(SB)/4, $0x000000ff DATA masks<>+0x9c(SB)/4, $0x00000000 - + DATA masks<>+0xa0(SB)/4, $0xffffffff DATA masks<>+0xa4(SB)/4, $0xffffffff DATA masks<>+0xa8(SB)/4, $0x0000ffff DATA masks<>+0xac(SB)/4, $0x00000000 - + DATA masks<>+0xb0(SB)/4, $0xffffffff DATA masks<>+0xb4(SB)/4, $0xffffffff DATA masks<>+0xb8(SB)/4, $0x00ffffff DATA masks<>+0xbc(SB)/4, $0x00000000 - + DATA masks<>+0xc0(SB)/4, $0xffffffff DATA masks<>+0xc4(SB)/4, $0xffffffff DATA masks<>+0xc8(SB)/4, $0xffffffff DATA masks<>+0xcc(SB)/4, $0x00000000 - + DATA masks<>+0xd0(SB)/4, $0xffffffff DATA masks<>+0xd4(SB)/4, $0xffffffff DATA masks<>+0xd8(SB)/4, $0xffffffff DATA masks<>+0xdc(SB)/4, $0x000000ff - + DATA masks<>+0xe0(SB)/4, $0xffffffff DATA masks<>+0xe4(SB)/4, $0xffffffff DATA masks<>+0xe8(SB)/4, $0xffffffff DATA masks<>+0xec(SB)/4, $0x0000ffff - + DATA masks<>+0xf0(SB)/4, $0xffffffff DATA masks<>+0xf4(SB)/4, $0xffffffff DATA masks<>+0xf8(SB)/4, $0xffffffff @@ -1217,77 +1217,77 @@ DATA shifts<>+0x00(SB)/4, $0x00000000 DATA shifts<>+0x04(SB)/4, $0x00000000 DATA shifts<>+0x08(SB)/4, $0x00000000 DATA shifts<>+0x0c(SB)/4, $0x00000000 - + DATA shifts<>+0x10(SB)/4, $0xffffff0f DATA shifts<>+0x14(SB)/4, $0xffffffff DATA shifts<>+0x18(SB)/4, $0xffffffff DATA shifts<>+0x1c(SB)/4, $0xffffffff - + DATA shifts<>+0x20(SB)/4, $0xffff0f0e DATA shifts<>+0x24(SB)/4, $0xffffffff DATA shifts<>+0x28(SB)/4, $0xffffffff DATA shifts<>+0x2c(SB)/4, $0xffffffff - + DATA shifts<>+0x30(SB)/4, $0xff0f0e0d DATA shifts<>+0x34(SB)/4, $0xffffffff DATA shifts<>+0x38(SB)/4, $0xffffffff DATA shifts<>+0x3c(SB)/4, $0xffffffff - + DATA shifts<>+0x40(SB)/4, $0x0f0e0d0c DATA shifts<>+0x44(SB)/4, $0xffffffff DATA shifts<>+0x48(SB)/4, $0xffffffff DATA shifts<>+0x4c(SB)/4, $0xffffffff - + DATA shifts<>+0x50(SB)/4, $0x0e0d0c0b DATA shifts<>+0x54(SB)/4, $0xffffff0f DATA shifts<>+0x58(SB)/4, $0xffffffff DATA shifts<>+0x5c(SB)/4, $0xffffffff - + DATA shifts<>+0x60(SB)/4, $0x0d0c0b0a DATA shifts<>+0x64(SB)/4, $0xffff0f0e DATA shifts<>+0x68(SB)/4, $0xffffffff DATA shifts<>+0x6c(SB)/4, $0xffffffff - + DATA shifts<>+0x70(SB)/4, $0x0c0b0a09 DATA shifts<>+0x74(SB)/4, $0xff0f0e0d DATA shifts<>+0x78(SB)/4, $0xffffffff DATA shifts<>+0x7c(SB)/4, $0xffffffff - + DATA shifts<>+0x80(SB)/4, $0x0b0a0908 DATA shifts<>+0x84(SB)/4, $0x0f0e0d0c DATA shifts<>+0x88(SB)/4, $0xffffffff DATA shifts<>+0x8c(SB)/4, $0xffffffff - + DATA shifts<>+0x90(SB)/4, $0x0a090807 DATA shifts<>+0x94(SB)/4, $0x0e0d0c0b DATA shifts<>+0x98(SB)/4, $0xffffff0f DATA shifts<>+0x9c(SB)/4, $0xffffffff - + DATA shifts<>+0xa0(SB)/4, $0x09080706 DATA shifts<>+0xa4(SB)/4, $0x0d0c0b0a DATA shifts<>+0xa8(SB)/4, $0xffff0f0e DATA shifts<>+0xac(SB)/4, $0xffffffff - + DATA shifts<>+0xb0(SB)/4, $0x08070605 DATA shifts<>+0xb4(SB)/4, $0x0c0b0a09 DATA shifts<>+0xb8(SB)/4, $0xff0f0e0d DATA shifts<>+0xbc(SB)/4, $0xffffffff - + DATA shifts<>+0xc0(SB)/4, $0x07060504 DATA shifts<>+0xc4(SB)/4, $0x0b0a0908 DATA shifts<>+0xc8(SB)/4, $0x0f0e0d0c DATA shifts<>+0xcc(SB)/4, $0xffffffff - + DATA shifts<>+0xd0(SB)/4, $0x06050403 DATA shifts<>+0xd4(SB)/4, $0x0a090807 DATA shifts<>+0xd8(SB)/4, $0x0e0d0c0b DATA shifts<>+0xdc(SB)/4, $0xffffff0f - + DATA shifts<>+0xe0(SB)/4, $0x05040302 DATA shifts<>+0xe4(SB)/4, $0x09080706 DATA shifts<>+0xe8(SB)/4, $0x0d0c0b0a DATA shifts<>+0xec(SB)/4, $0xffff0f0e - + DATA shifts<>+0xf0(SB)/4, $0x04030201 DATA shifts<>+0xf4(SB)/4, $0x08070605 DATA shifts<>+0xf8(SB)/4, $0x0c0b0a09 diff --git a/src/runtime/asm_amd64.s b/src/runtime/asm_amd64.s index 2a15910aea..ab891154c8 100644 --- a/src/runtime/asm_amd64.s +++ b/src/runtime/asm_amd64.s @@ -92,7 +92,7 @@ TEXT runtime·rt0_go(SB),NOSPLIT,$0 ANDQ $~15, SP MOVQ AX, 16(SP) MOVQ BX, 24(SP) - + // create istack out of the given (operating system) stack. // _cgo_init may update stackguard. MOVQ $runtime·g0(SB), DI @@ -273,7 +273,7 @@ TEXT runtime·gogo(SB), NOSPLIT, $16-8 // to keep running g. TEXT runtime·mcall(SB), NOSPLIT, $0-8 MOVQ fn+0(FP), DI - + get_tls(CX) MOVQ g(CX), AX // save state in g->sched MOVQ 0(SP), BX // caller's PC @@ -617,7 +617,7 @@ TEXT ·asmcgocall(SB),NOSPLIT,$0-20 MOVQ m_gsignal(R8), SI CMPQ SI, DI JEQ nosave - + // Switch to system stack. MOVQ m_g0(R8), SI CALL gosave<>(SB) @@ -717,7 +717,7 @@ needm: get_tls(CX) MOVQ g(CX), BX MOVQ g_m(BX), BX - + // Set m->sched.sp = SP, so that if a panic happens // during the function we are about to execute, it will // have a valid SP to run on the g0 stack. @@ -801,7 +801,7 @@ havem: MOVQ (g_sched+gobuf_sp)(SI), SP MOVQ 0(SP), AX MOVQ AX, (g_sched+gobuf_sp)(SI) - + // If the m on entry was nil, we called needm above to borrow an m // for the duration of the call. Since the call is over, return it with dropm. CMPQ R8, $0 @@ -953,7 +953,7 @@ aes17to32: // make second starting seed PXOR runtime·aeskeysched+16(SB), X1 AESENC X1, X1 - + // load data to be hashed MOVOU (AX), X2 MOVOU -16(AX)(CX*1), X3 @@ -985,7 +985,7 @@ aes33to64: AESENC X1, X1 AESENC X2, X2 AESENC X3, X3 - + MOVOU (AX), X4 MOVOU 16(AX), X5 MOVOU -32(AX)(CX*1), X6 @@ -995,17 +995,17 @@ aes33to64: PXOR X1, X5 PXOR X2, X6 PXOR X3, X7 - + AESENC X4, X4 AESENC X5, X5 AESENC X6, X6 AESENC X7, X7 - + AESENC X4, X4 AESENC X5, X5 AESENC X6, X6 AESENC X7, X7 - + AESENC X4, X4 AESENC X5, X5 AESENC X6, X6 @@ -1121,7 +1121,7 @@ aes129plus: AESENC X5, X5 AESENC X6, X6 AESENC X7, X7 - + // start with last (possibly overlapping) block MOVOU -128(AX)(CX*1), X8 MOVOU -112(AX)(CX*1), X9 @@ -1141,11 +1141,11 @@ aes129plus: PXOR X5, X13 PXOR X6, X14 PXOR X7, X15 - + // compute number of remaining 128-byte blocks DECQ CX SHRQ $7, CX - + aesloop: // scramble state AESENC X8, X8 diff --git a/src/runtime/asm_amd64p32.s b/src/runtime/asm_amd64p32.s index 49958d0c88..7f194d2403 100644 --- a/src/runtime/asm_amd64p32.s +++ b/src/runtime/asm_amd64p32.s @@ -18,7 +18,7 @@ TEXT runtime·rt0_go(SB),NOSPLIT,$0 MOVL AX, 16(SP) MOVL BX, 24(SP) - + // create istack out of the given (operating system) stack. MOVL $runtime·g0(SB), DI LEAL (-64*1024+104)(SP), BX @@ -150,7 +150,7 @@ TEXT runtime·gogo(SB), NOSPLIT, $8-4 // to keep running g. TEXT runtime·mcall(SB), NOSPLIT, $0-4 MOVL fn+0(FP), DI - + get_tls(CX) MOVL g(CX), AX // save state in g->sched MOVL 0(SP), BX // caller's PC diff --git a/src/runtime/asm_arm.s b/src/runtime/asm_arm.s index 6722ba760f..174dc46389 100644 --- a/src/runtime/asm_arm.s +++ b/src/runtime/asm_arm.s @@ -514,7 +514,7 @@ TEXT callRet<>(SB), NOSPLIT, $16-0 MOVW R1, 12(R13) MOVW R2, 16(R13) BL runtime·reflectcallmove(SB) - RET + RET CALLFN(·call16, 16) CALLFN(·call32, 32) @@ -673,7 +673,7 @@ TEXT runtime·cgocallback(SB),NOSPLIT,$16-16 // See cgocall.go for more details. TEXT ·cgocallback_gofunc(SB),NOSPLIT,$8-16 NO_LOCAL_POINTERS - + // Load m and g from thread-local storage. MOVB runtime·iscgo(SB), R0 CMP $0, R0 @@ -784,6 +784,9 @@ TEXT setg<>(SB),NOSPLIT|NOFRAME,$0-0 MOVW R0, g // Save g to thread-local storage. +#ifdef GOOS_windows + B runtime·save_g(SB) +#else MOVB runtime·iscgo(SB), R0 CMP $0, R0 B.EQ 2(PC) @@ -791,6 +794,7 @@ TEXT setg<>(SB),NOSPLIT|NOFRAME,$0-0 MOVW g, R0 RET +#endif TEXT runtime·emptyfunc(SB),0,$0-0 RET @@ -851,12 +855,12 @@ TEXT _cgo_topofstack(SB),NOSPLIT,$8 // callee-save in the gcc calling convention, so save them here. MOVW R11, saveR11-4(SP) MOVW g, saveG-8(SP) - + BL runtime·load_g(SB) MOVW g_m(g), R0 MOVW m_curg(R0), R0 MOVW (g_stack+stack_hi)(R0), R0 - + MOVW saveG-8(SP), g MOVW saveR11-4(SP), R11 RET diff --git a/src/runtime/asm_ppc64x.s b/src/runtime/asm_ppc64x.s index 57877c0194..b180cb06ab 100644 --- a/src/runtime/asm_ppc64x.s +++ b/src/runtime/asm_ppc64x.s @@ -390,15 +390,36 @@ TEXT NAME(SB), WRAPPER, $MAXSIZE-24; \ /* copy arguments to stack */ \ MOVD arg+16(FP), R3; \ MOVWZ argsize+24(FP), R4; \ - MOVD R1, R5; \ - ADD $(FIXED_FRAME-1), R5; \ - SUB $1, R3; \ - ADD R5, R4; \ - CMP R5, R4; \ - BEQ 4(PC); \ - MOVBZU 1(R3), R6; \ - MOVBZU R6, 1(R5); \ - BR -4(PC); \ + MOVD R1, R5; \ + CMP R4, $8; \ + BLT tailsetup; \ + /* copy 8 at a time if possible */ \ + ADD $(FIXED_FRAME-8), R5; \ + SUB $8, R3; \ +top: \ + MOVDU 8(R3), R7; \ + MOVDU R7, 8(R5); \ + SUB $8, R4; \ + CMP R4, $8; \ + BGE top; \ + /* handle remaining bytes */ \ + CMP $0, R4; \ + BEQ callfn; \ + ADD $7, R3; \ + ADD $7, R5; \ + BR tail; \ +tailsetup: \ + CMP $0, R4; \ + BEQ callfn; \ + ADD $(FIXED_FRAME-1), R5; \ + SUB $1, R3; \ +tail: \ + MOVBU 1(R3), R6; \ + MOVBU R6, 1(R5); \ + SUB $1, R4; \ + CMP $0, R4; \ + BGT tail; \ +callfn: \ /* call function */ \ MOVD f+8(FP), R11; \ MOVD (R11), R12; \ diff --git a/src/runtime/cgo/asm_amd64.s b/src/runtime/cgo/asm_amd64.s index 0e33fc4796..06c538b9bc 100644 --- a/src/runtime/cgo/asm_amd64.s +++ b/src/runtime/cgo/asm_amd64.s @@ -36,9 +36,9 @@ TEXT crosscall2(SB),NOSPLIT,$0x110-0 /* also need to save xmm6 - xmm15 */ MOVQ DX, 0x0(SP) /* arg */ MOVQ R8, 0x8(SP) /* argsize (includes padding) */ MOVQ R9, 0x10(SP) /* ctxt */ - + CALL CX /* fn */ - + MOVQ 0x48(SP), DI MOVQ 0x50(SP), SI MOVUPS 0x60(SP), X6 @@ -64,5 +64,5 @@ TEXT crosscall2(SB),NOSPLIT,$0x110-0 /* also need to save xmm6 - xmm15 */ MOVQ 0x30(SP), R13 MOVQ 0x38(SP), R14 MOVQ 0x40(SP), R15 - + RET diff --git a/src/runtime/cgo/asm_arm.s b/src/runtime/cgo/asm_arm.s index 36dab286ae..60132c14a8 100644 --- a/src/runtime/cgo/asm_arm.s +++ b/src/runtime/cgo/asm_arm.s @@ -8,7 +8,7 @@ // func crosscall2(fn func(a unsafe.Pointer, n int32, ctxt uintptr), a unsafe.Pointer, n int32, ctxt uintptr) // Saves C callee-saved registers and calls fn with three arguments. TEXT crosscall2(SB),NOSPLIT|NOFRAME,$0 - /* + /* * We still need to save all callee save register as before, and then * push 3 args for fn (R1, R2, R3). * Also note that at procedure entry in gc world, 4(R13) will be the diff --git a/src/runtime/cgo/signal_darwin_arm64.s b/src/runtime/cgo/signal_darwin_arm64.s index 60443b64c8..1ae00d13f3 100644 --- a/src/runtime/cgo/signal_darwin_arm64.s +++ b/src/runtime/cgo/signal_darwin_arm64.s @@ -37,7 +37,7 @@ ongothread: // Build a 32-byte stack frame for us for this call. // Saved LR (none available) is at the bottom, - // then the PC argument for setsigsegv, + // then the PC argument for setsigsegv, // then a copy of the LR for us to restore. MOVD.W $0, -32(RSP) MOVD R1, 8(RSP) diff --git a/src/runtime/cgocheck.go b/src/runtime/cgocheck.go index 73cb6ecae2..ac57e0344e 100644 --- a/src/runtime/cgocheck.go +++ b/src/runtime/cgocheck.go @@ -126,7 +126,7 @@ func cgoCheckTypedBlock(typ *_type, src unsafe.Pointer, off, size uintptr) { } s := spanOfUnchecked(uintptr(src)) - if s.state == _MSpanManual { + if s.state == mSpanManual { // There are no heap bits for value stored on the stack. // For a channel receive src might be on the stack of some // other goroutine, so we can't unwind the stack even if diff --git a/src/runtime/chan.go b/src/runtime/chan.go index 615643e6a6..5cf0b86f58 100644 --- a/src/runtime/chan.go +++ b/src/runtime/chan.go @@ -92,7 +92,7 @@ func makechan(t *chantype, size int) *hchan { // Queue or element size is zero. c = (*hchan)(mallocgc(hchanSize, nil, true)) // Race detector uses this location for synchronization. - c.buf = unsafe.Pointer(c) + c.buf = c.raceaddr() case elem.kind&kindNoPointers != 0: // Elements do not contain pointers. // Allocate hchan and buf in one call. @@ -151,7 +151,7 @@ func chansend(c *hchan, ep unsafe.Pointer, block bool, callerpc uintptr) bool { } if raceenabled { - racereadpc(unsafe.Pointer(c), callerpc, funcPC(chansend)) + racereadpc(c.raceaddr(), callerpc, funcPC(chansend)) } // Fast path: check for failed non-blocking operation without acquiring the lock. @@ -232,6 +232,11 @@ func chansend(c *hchan, ep unsafe.Pointer, block bool, callerpc uintptr) bool { gp.param = nil c.sendq.enqueue(mysg) goparkunlock(&c.lock, waitReasonChanSend, traceEvGoBlockSend, 3) + // Ensure the value being sent is kept alive until the + // receiver copies it out. The sudog has a pointer to the + // stack object, but sudogs aren't considered as roots of the + // stack tracer. + KeepAlive(ep) // someone woke us up. if mysg != gp.waiting { @@ -337,8 +342,8 @@ func closechan(c *hchan) { if raceenabled { callerpc := getcallerpc() - racewritepc(unsafe.Pointer(c), callerpc, funcPC(closechan)) - racerelease(unsafe.Pointer(c)) + racewritepc(c.raceaddr(), callerpc, funcPC(closechan)) + racerelease(c.raceaddr()) } c.closed = 1 @@ -361,7 +366,7 @@ func closechan(c *hchan) { gp := sg.g gp.param = nil if raceenabled { - raceacquireg(gp, unsafe.Pointer(c)) + raceacquireg(gp, c.raceaddr()) } glist.push(gp) } @@ -379,7 +384,7 @@ func closechan(c *hchan) { gp := sg.g gp.param = nil if raceenabled { - raceacquireg(gp, unsafe.Pointer(c)) + raceacquireg(gp, c.raceaddr()) } glist.push(gp) } @@ -454,7 +459,7 @@ func chanrecv(c *hchan, ep unsafe.Pointer, block bool) (selected, received bool) if c.closed != 0 && c.qcount == 0 { if raceenabled { - raceacquire(unsafe.Pointer(c)) + raceacquire(c.raceaddr()) } unlock(&c.lock) if ep != nil { @@ -732,6 +737,15 @@ func (q *waitq) dequeue() *sudog { } } +func (c *hchan) raceaddr() unsafe.Pointer { + // Treat read-like and write-like operations on the channel to + // happen at this address. Avoid using the address of qcount + // or dataqsiz, because the len() and cap() builtins read + // those addresses, and we don't want them racing with + // operations like close(). + return unsafe.Pointer(&c.buf) +} + func racesync(c *hchan, sg *sudog) { racerelease(chanbuf(c, 0)) raceacquireg(sg.g, chanbuf(c, 0)) diff --git a/src/runtime/crash_test.go b/src/runtime/crash_test.go index 2766b8850a..6835cacb3f 100644 --- a/src/runtime/crash_test.go +++ b/src/runtime/crash_test.go @@ -686,7 +686,7 @@ func init() { func TestRuntimePanic(t *testing.T) { testenv.MustHaveExec(t) - cmd := exec.Command(os.Args[0], "-test.run=TestRuntimePanic") + cmd := testenv.CleanCmdEnv(exec.Command(os.Args[0], "-test.run=TestRuntimePanic")) cmd.Env = append(cmd.Env, "GO_TEST_RUNTIME_PANIC=1") out, err := cmd.CombinedOutput() t.Logf("%s", out) diff --git a/src/runtime/crash_unix_test.go b/src/runtime/crash_unix_test.go index af9e6430da..1384e00210 100644 --- a/src/runtime/crash_unix_test.go +++ b/src/runtime/crash_unix_test.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux netbsd openbsd solaris +// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris package runtime_test diff --git a/src/runtime/debug_test.go b/src/runtime/debug_test.go index a34f4c77f7..37dcafd145 100644 --- a/src/runtime/debug_test.go +++ b/src/runtime/debug_test.go @@ -17,6 +17,8 @@ package runtime_test import ( "fmt" + "io/ioutil" + "regexp" "runtime" "runtime/debug" "sync/atomic" @@ -25,6 +27,11 @@ import ( ) func startDebugCallWorker(t *testing.T) (g *runtime.G, after func()) { + // This can deadlock if run under a debugger because it + // depends on catching SIGTRAP, which is usually swallowed by + // a debugger. + skipUnderDebugger(t) + // This can deadlock if there aren't enough threads or if a GC // tries to interrupt an atomic loop (see issue #10958). ogomaxprocs := runtime.GOMAXPROCS(2) @@ -73,6 +80,28 @@ func debugCallTKill(tid int) error { return syscall.Tgkill(syscall.Getpid(), tid, syscall.SIGTRAP) } +// skipUnderDebugger skips the current test when running under a +// debugger (specifically if this process has a tracer). This is +// Linux-specific. +func skipUnderDebugger(t *testing.T) { + pid := syscall.Getpid() + status, err := ioutil.ReadFile(fmt.Sprintf("/proc/%d/status", pid)) + if err != nil { + t.Logf("couldn't get proc tracer: %s", err) + return + } + re := regexp.MustCompile(`TracerPid:\s+([0-9]+)`) + sub := re.FindSubmatch(status) + if sub == nil { + t.Logf("couldn't find proc tracer PID") + return + } + if string(sub[1]) == "0" { + return + } + t.Skip("test will deadlock under a debugger") +} + func TestDebugCall(t *testing.T) { g, after := startDebugCallWorker(t) defer after() @@ -160,6 +189,8 @@ func debugCallUnsafePointWorker(gpp **runtime.G, ready, stop *uint32) { } func TestDebugCallUnsafePoint(t *testing.T) { + skipUnderDebugger(t) + // This can deadlock if there aren't enough threads or if a GC // tries to interrupt an atomic loop (see issue #10958). defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(2)) @@ -181,6 +212,8 @@ func TestDebugCallUnsafePoint(t *testing.T) { } func TestDebugCallPanic(t *testing.T) { + skipUnderDebugger(t) + // This can deadlock if there aren't enough threads. defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(2)) diff --git a/src/runtime/defs2_linux.go b/src/runtime/defs2_linux.go index c10dfb8624..b08c0dafe1 100644 --- a/src/runtime/defs2_linux.go +++ b/src/runtime/defs2_linux.go @@ -58,7 +58,10 @@ const ( MAP_PRIVATE = C.MAP_PRIVATE MAP_FIXED = C.MAP_FIXED - MADV_DONTNEED = C.MADV_DONTNEED + MADV_DONTNEED = C.MADV_DONTNEED + MADV_FREE = C.MADV_FREE + MADV_HUGEPAGE = C.MADV_HUGEPAGE + MADV_NOHUGEPAGE = C.MADV_HNOUGEPAGE SA_RESTART = C.SA_RESTART SA_ONSTACK = C.SA_ONSTACK diff --git a/src/runtime/defs_aix.go b/src/runtime/defs_aix.go new file mode 100644 index 0000000000..812c7fcfa2 --- /dev/null +++ b/src/runtime/defs_aix.go @@ -0,0 +1,170 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build ignore + +/* +Input to cgo -godefs +GOARCH=ppc64 go tool cgo -godefs defs_aix.go > defs_aix_ppc64_tmp.go + +This is only an helper to create defs_aix_ppc64.go +Go runtime functions require the "linux" name of fields (ss_sp, si_addr, etc) +However, AIX structures don't provide such names and must be modified. + +TODO(aix): create a script to automatise defs_aix creation. + +Modifications made: + - sigset replaced by a [4]uint64 array + - add sigset_all variable + - siginfo.si_addr uintptr instead of *byte + - add (*timeval) set_usec + - stackt.ss_sp uintptr instead of *byte + - stackt.ss_size uintptr instead of uint64 + - sigcontext.sc_jmpbuf context64 instead of jumbuf + - ucontext.__extctx is a uintptr because we don't need extctx struct + - ucontext.uc_mcontext: replace jumbuf structure by context64 structure + - sigaction.sa_handler represents union field as both are uintptr + - tstate.* replace *byte by uintptr + + +*/ + +package runtime + +/* + +#include <sys/types.h> +#include <sys/errno.h> +#include <sys/time.h> +#include <sys/signal.h> +#include <sys/mman.h> +#include <sys/thread.h> +#include <sys/resource.h> + +#include <unistd.h> +#include <fcntl.h> +#include <pthread.h> +#include <semaphore.h> +*/ +import "C" + +const ( + _EPERM = C.EPERM + _ENOENT = C.ENOENT + _EINTR = C.EINTR + _EAGAIN = C.EAGAIN + _ENOMEM = C.ENOMEM + _EACCES = C.EACCES + _EFAULT = C.EFAULT + _EINVAL = C.EINVAL + _ETIMEDOUT = C.ETIMEDOUT + + _PROT_NONE = C.PROT_NONE + _PROT_READ = C.PROT_READ + _PROT_WRITE = C.PROT_WRITE + _PROT_EXEC = C.PROT_EXEC + + _MAP_ANONYMOUS = C.MAP_ANONYMOUS + _MAP_PRIVATE = C.MAP_PRIVATE + _MAP_FIXED = C.MAP_FIXED + _MADV_DONTNEED = C.MADV_DONTNEED + + _SIGHUP = C.SIGHUP + _SIGINT = C.SIGINT + _SIGQUIT = C.SIGQUIT + _SIGILL = C.SIGILL + _SIGTRAP = C.SIGTRAP + _SIGABRT = C.SIGABRT + _SIGBUS = C.SIGBUS + _SIGFPE = C.SIGFPE + _SIGKILL = C.SIGKILL + _SIGUSR1 = C.SIGUSR1 + _SIGSEGV = C.SIGSEGV + _SIGUSR2 = C.SIGUSR2 + _SIGPIPE = C.SIGPIPE + _SIGALRM = C.SIGALRM + _SIGCHLD = C.SIGCHLD + _SIGCONT = C.SIGCONT + _SIGSTOP = C.SIGSTOP + _SIGTSTP = C.SIGTSTP + _SIGTTIN = C.SIGTTIN + _SIGTTOU = C.SIGTTOU + _SIGURG = C.SIGURG + _SIGXCPU = C.SIGXCPU + _SIGXFSZ = C.SIGXFSZ + _SIGVTALRM = C.SIGVTALRM + _SIGPROF = C.SIGPROF + _SIGWINCH = C.SIGWINCH + _SIGIO = C.SIGIO + _SIGPWR = C.SIGPWR + _SIGSYS = C.SIGSYS + _SIGTERM = C.SIGTERM + _SIGEMT = C.SIGEMT + _SIGWAITING = C.SIGWAITING + + _FPE_INTDIV = C.FPE_INTDIV + _FPE_INTOVF = C.FPE_INTOVF + _FPE_FLTDIV = C.FPE_FLTDIV + _FPE_FLTOVF = C.FPE_FLTOVF + _FPE_FLTUND = C.FPE_FLTUND + _FPE_FLTRES = C.FPE_FLTRES + _FPE_FLTINV = C.FPE_FLTINV + _FPE_FLTSUB = C.FPE_FLTSUB + + _BUS_ADRALN = C.BUS_ADRALN + _BUS_ADRERR = C.BUS_ADRERR + _BUS_OBJERR = C.BUS_OBJERR + + _SEGV_MAPERR = C.SEGV_MAPERR + _SEGV_ACCERR = C.SEGV_ACCERR + + _ITIMER_REAL = C.ITIMER_REAL + _ITIMER_VIRTUAL = C.ITIMER_VIRTUAL + _ITIMER_PROF = C.ITIMER_PROF + + _O_RDONLY = C.O_RDONLY + + _SS_DISABLE = C.SS_DISABLE + _SI_USER = C.SI_USER + _SIG_BLOCK = C.SIG_BLOCK + _SIG_UNBLOCK = C.SIG_UNBLOCK + _SIG_SETMASK = C.SIG_SETMASK + + _SA_SIGINFO = C.SA_SIGINFO + _SA_RESTART = C.SA_RESTART + _SA_ONSTACK = C.SA_ONSTACK + + _PTHREAD_CREATE_DETACHED = C.PTHREAD_CREATE_DETACHED + + __SC_PAGE_SIZE = C._SC_PAGE_SIZE + __SC_NPROCESSORS_ONLN = C._SC_NPROCESSORS_ONLN + + _F_SETFD = C.F_SETFD + _F_SETFL = C.F_SETFL + _F_GETFD = C.F_GETFD + _F_GETFL = C.F_GETFL + _FD_CLOEXEC = C.FD_CLOEXEC +) + +type sigset C.sigset_t +type siginfo C.siginfo_t +type timespec C.struct_timespec +type timestruc C.struct_timestruc_t +type timeval C.struct_timeval +type itimerval C.struct_itimerval + +type stackt C.stack_t +type sigcontext C.struct_sigcontext +type ucontext C.ucontext_t +type _Ctype_struct___extctx uint64 // ucontext use a pointer to this structure but it shouldn't be used +type jmpbuf C.struct___jmpbuf +type context64 C.struct___context64 +type sigactiont C.struct_sigaction +type tstate C.struct_tstate +type rusage C.struct_rusage + +type pthread C.pthread_t +type pthread_attr C.pthread_attr_t + +type semt C.sem_t diff --git a/src/runtime/defs_aix_ppc64.go b/src/runtime/defs_aix_ppc64.go new file mode 100644 index 0000000000..e7480d06ba --- /dev/null +++ b/src/runtime/defs_aix_ppc64.go @@ -0,0 +1,203 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build aix + +package runtime + +const ( + _EPERM = 0x1 + _ENOENT = 0x2 + _EINTR = 0x4 + _EAGAIN = 0xb + _ENOMEM = 0xc + _EACCES = 0xd + _EFAULT = 0xe + _EINVAL = 0x16 + _ETIMEDOUT = 0x4e + + _PROT_NONE = 0x0 + _PROT_READ = 0x1 + _PROT_WRITE = 0x2 + _PROT_EXEC = 0x4 + + _MAP_ANONYMOUS = 0x10 + _MAP_PRIVATE = 0x2 + _MAP_FIXED = 0x100 + _MADV_DONTNEED = 0x4 + + _SIGHUP = 0x1 + _SIGINT = 0x2 + _SIGQUIT = 0x3 + _SIGILL = 0x4 + _SIGTRAP = 0x5 + _SIGABRT = 0x6 + _SIGBUS = 0xa + _SIGFPE = 0x8 + _SIGKILL = 0x9 + _SIGUSR1 = 0x1e + _SIGSEGV = 0xb + _SIGUSR2 = 0x1f + _SIGPIPE = 0xd + _SIGALRM = 0xe + _SIGCHLD = 0x14 + _SIGCONT = 0x13 + _SIGSTOP = 0x11 + _SIGTSTP = 0x12 + _SIGTTIN = 0x15 + _SIGTTOU = 0x16 + _SIGURG = 0x10 + _SIGXCPU = 0x18 + _SIGXFSZ = 0x19 + _SIGVTALRM = 0x22 + _SIGPROF = 0x20 + _SIGWINCH = 0x1c + _SIGIO = 0x17 + _SIGPWR = 0x1d + _SIGSYS = 0xc + _SIGTERM = 0xf + _SIGEMT = 0x7 + _SIGWAITING = 0x27 + + _FPE_INTDIV = 0x14 + _FPE_INTOVF = 0x15 + _FPE_FLTDIV = 0x16 + _FPE_FLTOVF = 0x17 + _FPE_FLTUND = 0x18 + _FPE_FLTRES = 0x19 + _FPE_FLTINV = 0x1a + _FPE_FLTSUB = 0x1b + + _BUS_ADRALN = 0x1 + _BUS_ADRERR = 0x2 + _BUS_OBJERR = 0x3 + _ + _SEGV_MAPERR = 0x32 + _SEGV_ACCERR = 0x33 + + _ITIMER_REAL = 0x0 + _ITIMER_VIRTUAL = 0x1 + _ITIMER_PROF = 0x2 + + _O_RDONLY = 0x0 + + _SS_DISABLE = 0x2 + _SI_USER = 0x0 + _SIG_BLOCK = 0x0 + _SIG_UNBLOCK = 0x1 + _SIG_SETMASK = 0x2 + + _SA_SIGINFO = 0x100 + _SA_RESTART = 0x8 + _SA_ONSTACK = 0x1 + + _PTHREAD_CREATE_DETACHED = 0x1 + + __SC_PAGE_SIZE = 0x30 + __SC_NPROCESSORS_ONLN = 0x48 + + _F_SETFD = 0x2 + _F_SETFL = 0x4 + _F_GETFD = 0x1 + _F_GETFL = 0x3 + _FD_CLOEXEC = 0x1 +) + +type sigset [4]uint64 + +var sigset_all = sigset{^uint64(0), ^uint64(0), ^uint64(0), ^uint64(0)} + +type siginfo struct { + si_signo int32 + si_errno int32 + si_code int32 + si_pid int32 + si_uid uint32 + si_status int32 + si_addr uintptr + si_band int64 + si_value [2]int32 // [8]byte + __si_flags int32 + __pad [3]int32 +} + +type timespec struct { + tv_sec int64 + tv_nsec int64 +} +type timeval struct { + tv_sec int64 + tv_usec int32 + pad_cgo_0 [4]byte +} + +func (tv *timeval) set_usec(x int32) { + tv.tv_usec = x +} + +type itimerval struct { + it_interval timeval + it_value timeval +} + +type stackt struct { + ss_sp uintptr + ss_size uintptr + ss_flags int32 + __pad [4]int32 + pas_cgo_0 [4]byte +} + +type sigcontext struct { + sc_onstack int32 + pad_cgo_0 [4]byte + sc_mask sigset + sc_uerror int32 + sc_jmpbuf context64 +} + +type ucontext struct { + __sc_onstack int32 + pad_cgo_0 [4]byte + uc_sigmask sigset + __sc_error int32 + pad_cgo_1 [4]byte + uc_mcontext context64 + uc_link *ucontext + uc_stack stackt + __extctx uintptr // pointer to struct __extctx but we don't use it + __extctx_magic int32 + __pad int32 +} + +type context64 struct { + gpr [32]uint64 + msr uint64 + iar uint64 + lr uint64 + ctr uint64 + cr uint32 + xer uint32 + fpscr uint32 + fpscrx uint32 + except [1]uint64 + fpr [32]float64 + fpeu uint8 + fpinfo uint8 + fpscr24_31 uint8 + pad [1]uint8 + excp_type int32 +} + +type sigactiont struct { + sa_handler uintptr // a union of two pointer + sa_mask sigset + sa_flags int32 + pad_cgo_0 [4]byte +} + +type pthread uint32 +type pthread_attr *byte + +type semt int32 diff --git a/src/runtime/defs_linux.go b/src/runtime/defs_linux.go index 553366a50b..2d810136d9 100644 --- a/src/runtime/defs_linux.go +++ b/src/runtime/defs_linux.go @@ -47,7 +47,10 @@ const ( MAP_PRIVATE = C.MAP_PRIVATE MAP_FIXED = C.MAP_FIXED - MADV_DONTNEED = C.MADV_DONTNEED + MADV_DONTNEED = C.MADV_DONTNEED + MADV_FREE = C.MADV_FREE + MADV_HUGEPAGE = C.MADV_HUGEPAGE + MADV_NOHUGEPAGE = C.MADV_HNOUGEPAGE SA_RESTART = C.SA_RESTART SA_ONSTACK = C.SA_ONSTACK diff --git a/src/runtime/defs_linux_386.go b/src/runtime/defs_linux_386.go index a7e435f854..0ebac17aef 100644 --- a/src/runtime/defs_linux_386.go +++ b/src/runtime/defs_linux_386.go @@ -18,6 +18,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_linux_amd64.go b/src/runtime/defs_linux_amd64.go index e8c6a212db..c0a0ef0dd4 100644 --- a/src/runtime/defs_linux_amd64.go +++ b/src/runtime/defs_linux_amd64.go @@ -18,6 +18,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_linux_arm.go b/src/runtime/defs_linux_arm.go index 62ec8fab5e..43946bb79c 100644 --- a/src/runtime/defs_linux_arm.go +++ b/src/runtime/defs_linux_arm.go @@ -16,6 +16,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_linux_arm64.go b/src/runtime/defs_linux_arm64.go index c295bc0257..c2cc281ab4 100644 --- a/src/runtime/defs_linux_arm64.go +++ b/src/runtime/defs_linux_arm64.go @@ -18,6 +18,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_linux_mips64x.go b/src/runtime/defs_linux_mips64x.go index df11cb0965..9dacd5d1e9 100644 --- a/src/runtime/defs_linux_mips64x.go +++ b/src/runtime/defs_linux_mips64x.go @@ -18,6 +18,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_linux_mipsx.go b/src/runtime/defs_linux_mipsx.go index 702fbb51c8..9532ac54ee 100644 --- a/src/runtime/defs_linux_mipsx.go +++ b/src/runtime/defs_linux_mipsx.go @@ -22,6 +22,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_linux_ppc64.go b/src/runtime/defs_linux_ppc64.go index 45363d1285..5a4326da07 100644 --- a/src/runtime/defs_linux_ppc64.go +++ b/src/runtime/defs_linux_ppc64.go @@ -18,6 +18,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_linux_ppc64le.go b/src/runtime/defs_linux_ppc64le.go index 45363d1285..5a4326da07 100644 --- a/src/runtime/defs_linux_ppc64le.go +++ b/src/runtime/defs_linux_ppc64le.go @@ -18,6 +18,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_linux_s390x.go b/src/runtime/defs_linux_s390x.go index ab90723f75..a6cc9c48e9 100644 --- a/src/runtime/defs_linux_s390x.go +++ b/src/runtime/defs_linux_s390x.go @@ -19,6 +19,7 @@ const ( _MAP_FIXED = 0x10 _MADV_DONTNEED = 0x4 + _MADV_FREE = 0x8 _MADV_HUGEPAGE = 0xe _MADV_NOHUGEPAGE = 0xf diff --git a/src/runtime/defs_windows_386.go b/src/runtime/defs_windows_386.go index 589a7884cd..38b30b70e3 100644 --- a/src/runtime/defs_windows_386.go +++ b/src/runtime/defs_windows_386.go @@ -104,6 +104,9 @@ type context struct { func (c *context) ip() uintptr { return uintptr(c.eip) } func (c *context) sp() uintptr { return uintptr(c.esp) } +// 386 does not have link register, so this returns 0. +func (c *context) lr() uintptr { return 0 } + func (c *context) setip(x uintptr) { c.eip = uint32(x) } func (c *context) setsp(x uintptr) { c.esp = uint32(x) } diff --git a/src/runtime/defs_windows_amd64.go b/src/runtime/defs_windows_amd64.go index 1e173e934d..37508c09be 100644 --- a/src/runtime/defs_windows_amd64.go +++ b/src/runtime/defs_windows_amd64.go @@ -119,6 +119,9 @@ type context struct { func (c *context) ip() uintptr { return uintptr(c.rip) } func (c *context) sp() uintptr { return uintptr(c.rsp) } +// Amd64 does not have link register, so this returns 0. +func (c *context) lr() uintptr { return 0 } + func (c *context) setip(x uintptr) { c.rip = uint64(x) } func (c *context) setsp(x uintptr) { c.rsp = uint64(x) } diff --git a/src/runtime/defs_windows_arm.go b/src/runtime/defs_windows_arm.go new file mode 100644 index 0000000000..1140f61651 --- /dev/null +++ b/src/runtime/defs_windows_arm.go @@ -0,0 +1,149 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package runtime + +const ( + _PROT_NONE = 0 + _PROT_READ = 1 + _PROT_WRITE = 2 + _PROT_EXEC = 4 + + _MAP_ANON = 1 + _MAP_PRIVATE = 2 + + _DUPLICATE_SAME_ACCESS = 0x2 + _THREAD_PRIORITY_HIGHEST = 0x2 + + _SIGINT = 0x2 + _CTRL_C_EVENT = 0x0 + _CTRL_BREAK_EVENT = 0x1 + + _CONTEXT_CONTROL = 0x10001 + _CONTEXT_FULL = 0x10007 + + _EXCEPTION_ACCESS_VIOLATION = 0xc0000005 + _EXCEPTION_BREAKPOINT = 0x80000003 + _EXCEPTION_FLT_DENORMAL_OPERAND = 0xc000008d + _EXCEPTION_FLT_DIVIDE_BY_ZERO = 0xc000008e + _EXCEPTION_FLT_INEXACT_RESULT = 0xc000008f + _EXCEPTION_FLT_OVERFLOW = 0xc0000091 + _EXCEPTION_FLT_UNDERFLOW = 0xc0000093 + _EXCEPTION_INT_DIVIDE_BY_ZERO = 0xc0000094 + _EXCEPTION_INT_OVERFLOW = 0xc0000095 + + _INFINITE = 0xffffffff + _WAIT_TIMEOUT = 0x102 + + _EXCEPTION_CONTINUE_EXECUTION = -0x1 + _EXCEPTION_CONTINUE_SEARCH = 0x0 +) + +type systeminfo struct { + anon0 [4]byte + dwpagesize uint32 + lpminimumapplicationaddress *byte + lpmaximumapplicationaddress *byte + dwactiveprocessormask uint32 + dwnumberofprocessors uint32 + dwprocessortype uint32 + dwallocationgranularity uint32 + wprocessorlevel uint16 + wprocessorrevision uint16 +} + +type exceptionrecord struct { + exceptioncode uint32 + exceptionflags uint32 + exceptionrecord *exceptionrecord + exceptionaddress *byte + numberparameters uint32 + exceptioninformation [15]uint32 +} + +type neon128 struct { + low uint64 + high int64 +} + +type context struct { + contextflags uint32 + r0 uint32 + r1 uint32 + r2 uint32 + r3 uint32 + r4 uint32 + r5 uint32 + r6 uint32 + r7 uint32 + r8 uint32 + r9 uint32 + r10 uint32 + r11 uint32 + r12 uint32 + + spr uint32 + lrr uint32 + pc uint32 + cpsr uint32 + + fpscr uint32 + padding uint32 + + floatNeon [16]neon128 + + bvr [8]uint32 + bcr [8]uint32 + wvr [1]uint32 + wcr [1]uint32 + padding2 [2]uint32 +} + +func (c *context) ip() uintptr { return uintptr(c.pc) } +func (c *context) sp() uintptr { return uintptr(c.spr) } +func (c *context) lr() uintptr { return uintptr(c.lrr) } + +func (c *context) setip(x uintptr) { c.pc = uint32(x) } +func (c *context) setsp(x uintptr) { c.spr = uint32(x) } + +func dumpregs(r *context) { + print("r0 ", hex(r.r0), "\n") + print("r1 ", hex(r.r1), "\n") + print("r2 ", hex(r.r2), "\n") + print("r3 ", hex(r.r3), "\n") + print("r4 ", hex(r.r4), "\n") + print("r5 ", hex(r.r5), "\n") + print("r6 ", hex(r.r6), "\n") + print("r7 ", hex(r.r7), "\n") + print("r8 ", hex(r.r8), "\n") + print("r9 ", hex(r.r9), "\n") + print("r10 ", hex(r.r10), "\n") + print("r11 ", hex(r.r11), "\n") + print("r12 ", hex(r.r12), "\n") + print("sp ", hex(r.spr), "\n") + print("lr ", hex(r.lrr), "\n") + print("pc ", hex(r.pc), "\n") + print("cpsr ", hex(r.cpsr), "\n") +} + +type overlapped struct { + internal uint32 + internalhigh uint32 + anon0 [8]byte + hevent *byte +} + +type memoryBasicInformation struct { + baseAddress uintptr + allocationBase uintptr + allocationProtect uint32 + regionSize uintptr + state uint32 + protect uint32 + type_ uint32 +} + +func stackcheck() { + // TODO: not implemented on ARM +} diff --git a/src/runtime/env_posix.go b/src/runtime/env_posix.go index 032e7122ce..a2daeb7f27 100644 --- a/src/runtime/env_posix.go +++ b/src/runtime/env_posix.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris windows +// +build aix darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris windows package runtime diff --git a/src/runtime/export_unix_test.go b/src/runtime/export_unix_test.go index 54d577072e..eecdfb7eb2 100644 --- a/src/runtime/export_unix_test.go +++ b/src/runtime/export_unix_test.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux netbsd openbsd solaris +// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris package runtime diff --git a/src/runtime/extern.go b/src/runtime/extern.go index 1773c8fe7e..640688e004 100644 --- a/src/runtime/extern.go +++ b/src/runtime/extern.go @@ -50,19 +50,13 @@ It is a comma-separated list of name=val pairs setting these named variables: gcshrinkstackoff: setting gcshrinkstackoff=1 disables moving goroutines onto smaller stacks. In this mode, a goroutine's stack can only grow. - gcrescanstacks: setting gcrescanstacks=1 enables stack - re-scanning during the STW mark termination phase. This is - helpful for debugging if objects are being prematurely - garbage collected. - gcstoptheworld: setting gcstoptheworld=1 disables concurrent garbage collection, making every garbage collection a stop-the-world event. Setting gcstoptheworld=2 also disables concurrent sweeping after the garbage collection finishes. gctrace: setting gctrace=1 causes the garbage collector to emit a single line to standard error at each collection, summarizing the amount of memory collected and the - length of the pause. Setting gctrace=2 emits the same summary but also - repeats each collection. The format of this line is subject to change. + length of the pause. The format of this line is subject to change. Currently, it is: gc # @#s #%: #+#+# ms clock, #+#/#/#+# ms cpu, #->#-># MB, # MB goal, # P where the fields are as follows: diff --git a/src/runtime/funcdata.h b/src/runtime/funcdata.h index e6e0306e65..1ee67c8683 100644 --- a/src/runtime/funcdata.h +++ b/src/runtime/funcdata.h @@ -16,6 +16,7 @@ #define FUNCDATA_LocalsPointerMaps 1 #define FUNCDATA_InlTree 2 #define FUNCDATA_RegPointerMaps 3 +#define FUNCDATA_StackObjects 4 // Pseudo-assembly statements. diff --git a/src/runtime/gc_test.go b/src/runtime/gc_test.go index 0da19cdf34..51e8ea4d31 100644 --- a/src/runtime/gc_test.go +++ b/src/runtime/gc_test.go @@ -24,6 +24,9 @@ func TestGcSys(t *testing.T) { if runtime.GOOS == "windows" { t.Skip("skipping test; GOOS=windows http://golang.org/issue/27156") } + if runtime.GOOS == "linux" && runtime.GOARCH == "arm64" { + t.Skip("skipping test; GOOS=linux GOARCH=arm64 https://github.com/golang/go/issues/27636") + } got := runTestProg(t, "testprog", "GCSys") want := "OK\n" if got != want { @@ -571,8 +574,8 @@ func BenchmarkWriteBarrier(b *testing.B) { n := &node{mkTree(level - 1), mkTree(level - 1)} if level == 10 { // Seed GC with enough early pointers so it - // doesn't accidentally switch to mark 2 when - // it only has the top of the tree. + // doesn't start termination barriers when it + // only has the top of the tree. wbRoots = append(wbRoots, n) } return n diff --git a/src/runtime/gcinfo_test.go b/src/runtime/gcinfo_test.go index 7dd1a5607c..0741f6361c 100644 --- a/src/runtime/gcinfo_test.go +++ b/src/runtime/gcinfo_test.go @@ -35,14 +35,46 @@ func TestGCInfo(t *testing.T) { verifyGCInfo(t, "data eface", &dataEface, infoEface) verifyGCInfo(t, "data iface", &dataIface, infoIface) - verifyGCInfo(t, "stack Ptr", new(Ptr), infoPtr) - verifyGCInfo(t, "stack ScalarPtr", new(ScalarPtr), infoScalarPtr) - verifyGCInfo(t, "stack PtrScalar", new(PtrScalar), infoPtrScalar) - verifyGCInfo(t, "stack BigStruct", new(BigStruct), infoBigStruct()) - verifyGCInfo(t, "stack string", new(string), infoString) - verifyGCInfo(t, "stack slice", new([]string), infoSlice) - verifyGCInfo(t, "stack eface", new(interface{}), infoEface) - verifyGCInfo(t, "stack iface", new(Iface), infoIface) + { + var x Ptr + verifyGCInfo(t, "stack Ptr", &x, infoPtr) + runtime.KeepAlive(x) + } + { + var x ScalarPtr + verifyGCInfo(t, "stack ScalarPtr", &x, infoScalarPtr) + runtime.KeepAlive(x) + } + { + var x PtrScalar + verifyGCInfo(t, "stack PtrScalar", &x, infoPtrScalar) + runtime.KeepAlive(x) + } + { + var x BigStruct + verifyGCInfo(t, "stack BigStruct", &x, infoBigStruct()) + runtime.KeepAlive(x) + } + { + var x string + verifyGCInfo(t, "stack string", &x, infoString) + runtime.KeepAlive(x) + } + { + var x []string + verifyGCInfo(t, "stack slice", &x, infoSlice) + runtime.KeepAlive(x) + } + { + var x interface{} + verifyGCInfo(t, "stack eface", &x, infoEface) + runtime.KeepAlive(x) + } + { + var x Iface + verifyGCInfo(t, "stack iface", &x, infoIface) + runtime.KeepAlive(x) + } for i := 0; i < 10; i++ { verifyGCInfo(t, "heap Ptr", escape(new(Ptr)), trimDead(padDead(infoPtr))) diff --git a/src/runtime/heapdump.go b/src/runtime/heapdump.go index 0fc02a8e80..eadbcaeee1 100644 --- a/src/runtime/heapdump.go +++ b/src/runtime/heapdump.go @@ -346,7 +346,7 @@ func dumpgoroutine(gp *g) { dumpint(uint64(gp.goid)) dumpint(uint64(gp.gopc)) dumpint(uint64(readgstatus(gp))) - dumpbool(isSystemGoroutine(gp)) + dumpbool(isSystemGoroutine(gp, false)) dumpbool(false) // isbackground dumpint(uint64(gp.waitsince)) dumpstr(gp.waitreason.String()) @@ -430,7 +430,7 @@ func dumproots() { // MSpan.types for _, s := range mheap_.allspans { - if s.state == _MSpanInUse { + if s.state == mSpanInUse { // Finalizers for sp := s.specials; sp != nil; sp = sp.next { if sp.kind != _KindSpecialFinalizer { @@ -453,7 +453,7 @@ var freemark [_PageSize / 8]bool func dumpobjs() { for _, s := range mheap_.allspans { - if s.state != _MSpanInUse { + if s.state != mSpanInUse { continue } p := s.base() @@ -616,7 +616,7 @@ func dumpmemprof_callback(b *bucket, nstk uintptr, pstk *uintptr, size, allocs, func dumpmemprof() { iterate_memprof(dumpmemprof_callback) for _, s := range mheap_.allspans { - if s.state != _MSpanInUse { + if s.state != mSpanInUse { continue } for sp := s.specials; sp != nil; sp = sp.next { @@ -637,7 +637,7 @@ var dumphdr = []byte("go1.7 heap dump\n") func mdump() { // make sure we're done sweeping for _, s := range mheap_.allspans { - if s.state == _MSpanInUse { + if s.state == mSpanInUse { s.ensureSwept() } } diff --git a/src/runtime/internal/sys/zgoos_aix.go b/src/runtime/internal/sys/zgoos_aix.go new file mode 100644 index 0000000000..9ce5b3434f --- /dev/null +++ b/src/runtime/internal/sys/zgoos_aix.go @@ -0,0 +1,21 @@ +// Code generated by gengoos.go using 'go generate'. DO NOT EDIT. + +// +build aix + +package sys + +const GOOS = `aix` + +const GoosAndroid = 0 +const GoosAix = 1 +const GoosDarwin = 0 +const GoosDragonfly = 0 +const GoosFreebsd = 0 +const GoosLinux = 0 +const GoosNacl = 0 +const GoosNetbsd = 0 +const GoosOpenbsd = 0 +const GoosPlan9 = 0 +const GoosSolaris = 0 +const GoosWindows = 0 +const GoosZos = 0 diff --git a/src/runtime/internal/sys/zgoos_android.go b/src/runtime/internal/sys/zgoos_android.go index bfdc37792e..36a5768ab6 100644 --- a/src/runtime/internal/sys/zgoos_android.go +++ b/src/runtime/internal/sys/zgoos_android.go @@ -7,6 +7,7 @@ package sys const GOOS = `android` const GoosAndroid = 1 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_darwin.go b/src/runtime/internal/sys/zgoos_darwin.go index 1c4667f6de..10c0e88e9a 100644 --- a/src/runtime/internal/sys/zgoos_darwin.go +++ b/src/runtime/internal/sys/zgoos_darwin.go @@ -7,6 +7,7 @@ package sys const GOOS = `darwin` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 1 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_dragonfly.go b/src/runtime/internal/sys/zgoos_dragonfly.go index 728bf6abe8..5cb47cb84e 100644 --- a/src/runtime/internal/sys/zgoos_dragonfly.go +++ b/src/runtime/internal/sys/zgoos_dragonfly.go @@ -7,6 +7,7 @@ package sys const GOOS = `dragonfly` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 1 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_freebsd.go b/src/runtime/internal/sys/zgoos_freebsd.go index a8d659169b..470406ce5f 100644 --- a/src/runtime/internal/sys/zgoos_freebsd.go +++ b/src/runtime/internal/sys/zgoos_freebsd.go @@ -7,6 +7,7 @@ package sys const GOOS = `freebsd` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 1 diff --git a/src/runtime/internal/sys/zgoos_linux.go b/src/runtime/internal/sys/zgoos_linux.go index 289400c612..76235b748c 100644 --- a/src/runtime/internal/sys/zgoos_linux.go +++ b/src/runtime/internal/sys/zgoos_linux.go @@ -8,6 +8,7 @@ package sys const GOOS = `linux` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_nacl.go b/src/runtime/internal/sys/zgoos_nacl.go index 3fedb0a2c3..6d28b59667 100644 --- a/src/runtime/internal/sys/zgoos_nacl.go +++ b/src/runtime/internal/sys/zgoos_nacl.go @@ -7,6 +7,7 @@ package sys const GOOS = `nacl` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_netbsd.go b/src/runtime/internal/sys/zgoos_netbsd.go index 3346e3711c..ef8d938ddb 100644 --- a/src/runtime/internal/sys/zgoos_netbsd.go +++ b/src/runtime/internal/sys/zgoos_netbsd.go @@ -7,6 +7,7 @@ package sys const GOOS = `netbsd` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_openbsd.go b/src/runtime/internal/sys/zgoos_openbsd.go index 13c0323249..2e43847396 100644 --- a/src/runtime/internal/sys/zgoos_openbsd.go +++ b/src/runtime/internal/sys/zgoos_openbsd.go @@ -7,6 +7,7 @@ package sys const GOOS = `openbsd` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_plan9.go b/src/runtime/internal/sys/zgoos_plan9.go index 6b2e977b5e..ed598dcaac 100644 --- a/src/runtime/internal/sys/zgoos_plan9.go +++ b/src/runtime/internal/sys/zgoos_plan9.go @@ -7,6 +7,7 @@ package sys const GOOS = `plan9` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_solaris.go b/src/runtime/internal/sys/zgoos_solaris.go index cbf70f079a..fe690df6c2 100644 --- a/src/runtime/internal/sys/zgoos_solaris.go +++ b/src/runtime/internal/sys/zgoos_solaris.go @@ -7,6 +7,7 @@ package sys const GOOS = `solaris` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_windows.go b/src/runtime/internal/sys/zgoos_windows.go index 70839ca793..ea7c43bdf4 100644 --- a/src/runtime/internal/sys/zgoos_windows.go +++ b/src/runtime/internal/sys/zgoos_windows.go @@ -7,6 +7,7 @@ package sys const GOOS = `windows` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/internal/sys/zgoos_zos.go b/src/runtime/internal/sys/zgoos_zos.go index ecf449f703..d4027cf876 100644 --- a/src/runtime/internal/sys/zgoos_zos.go +++ b/src/runtime/internal/sys/zgoos_zos.go @@ -7,6 +7,7 @@ package sys const GOOS = `zos` const GoosAndroid = 0 +const GoosAix = 0 const GoosDarwin = 0 const GoosDragonfly = 0 const GoosFreebsd = 0 diff --git a/src/runtime/lock_sema.go b/src/runtime/lock_sema.go index 6e01d70f75..d21a055685 100644 --- a/src/runtime/lock_sema.go +++ b/src/runtime/lock_sema.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin nacl netbsd openbsd plan9 solaris windows +// +build aix darwin nacl netbsd openbsd plan9 solaris windows package runtime diff --git a/src/runtime/malloc.go b/src/runtime/malloc.go index 07e0a67240..c3fe1169dc 100644 --- a/src/runtime/malloc.go +++ b/src/runtime/malloc.go @@ -124,8 +124,6 @@ const ( // have the most objects per span. maxObjsPerSpan = pageSize / 8 - mSpanInUse = _MSpanInUse - concurrentSweep = _ConcurrentSweep _PageSize = 1 << _PageShift @@ -328,27 +326,27 @@ var physPageSize uintptr // may use larger alignment, so the caller must be careful to realign the // memory obtained by sysAlloc. // -// SysUnused notifies the operating system that the contents +// sysUnused notifies the operating system that the contents // of the memory region are no longer needed and can be reused // for other purposes. -// SysUsed notifies the operating system that the contents +// sysUsed notifies the operating system that the contents // of the memory region are needed again. // -// SysFree returns it unconditionally; this is only used if +// sysFree returns it unconditionally; this is only used if // an out-of-memory error has been detected midway through -// an allocation. It is okay if SysFree is a no-op. +// an allocation. It is okay if sysFree is a no-op. // -// SysReserve reserves address space without allocating memory. +// sysReserve reserves address space without allocating memory. // If the pointer passed to it is non-nil, the caller wants the -// reservation there, but SysReserve can still choose another +// reservation there, but sysReserve can still choose another // location if that one is unavailable. -// NOTE: SysReserve returns OS-aligned memory, but the heap allocator +// NOTE: sysReserve returns OS-aligned memory, but the heap allocator // may use larger alignment, so the caller must be careful to realign the // memory obtained by sysAlloc. // -// SysMap maps previously reserved address space for use. +// sysMap maps previously reserved address space for use. // -// SysFault marks a (already sysAlloc'd) region to fault +// sysFault marks a (already sysAlloc'd) region to fault // if accessed. Used only for debugging the runtime. func mallocinit() { @@ -735,6 +733,9 @@ func nextFreeFast(s *mspan) gclinkptr { // weight allocation. If it is a heavy weight allocation the caller must // determine whether a new GC cycle needs to be started or if the GC is active // whether this goroutine needs to assist the GC. +// +// Must run in a non-preemptible context since otherwise the owner of +// c could change. func (c *mcache) nextFree(spc spanClass) (v gclinkptr, s *mspan, shouldhelpgc bool) { s = c.alloc[spc] shouldhelpgc = false @@ -745,9 +746,7 @@ func (c *mcache) nextFree(spc spanClass) (v gclinkptr, s *mspan, shouldhelpgc bo println("runtime: s.allocCount=", s.allocCount, "s.nelems=", s.nelems) throw("s.allocCount != s.nelems && freeIndex == s.nelems") } - systemstack(func() { - c.refill(spc) - }) + c.refill(spc) shouldhelpgc = true s = c.alloc[spc] @@ -993,7 +992,7 @@ func mallocgc(size uintptr, typ *_type, needzero bool) unsafe.Pointer { if shouldhelpgc { if t := (gcTrigger{kind: gcTriggerHeap}); t.test() { - gcStart(gcBackgroundMode, t) + gcStart(t) } } diff --git a/src/runtime/mbarrier.go b/src/runtime/mbarrier.go index 5142f4327a..6da8cf2ccb 100644 --- a/src/runtime/mbarrier.go +++ b/src/runtime/mbarrier.go @@ -318,6 +318,19 @@ func typedmemclr(typ *_type, ptr unsafe.Pointer) { memclrNoHeapPointers(ptr, typ.size) } +//go:linkname reflect_typedmemclr reflect.typedmemclr +func reflect_typedmemclr(typ *_type, ptr unsafe.Pointer) { + typedmemclr(typ, ptr) +} + +//go:linkname reflect_typedmemclrpartial reflect.typedmemclrpartial +func reflect_typedmemclrpartial(typ *_type, ptr unsafe.Pointer, off, size uintptr) { + if typ.kind&kindNoPointers == 0 { + bulkBarrierPreWrite(uintptr(ptr), 0, size) + } + memclrNoHeapPointers(ptr, size) +} + // memclrHasPointers clears n bytes of typed memory starting at ptr. // The caller must ensure that the type of the object at ptr has // pointers, usually by checking typ.kind&kindNoPointers. However, ptr diff --git a/src/runtime/mbitmap.go b/src/runtime/mbitmap.go index e217e7695f..87fa027b4e 100644 --- a/src/runtime/mbitmap.go +++ b/src/runtime/mbitmap.go @@ -365,7 +365,7 @@ func findObject(p, refBase, refOff uintptr) (base uintptr, s *mspan, objIndex ui s = spanOf(p) // If p is a bad pointer, it may not be in s's bounds. if s == nil || p < s.base() || p >= s.limit || s.state != mSpanInUse { - if s == nil || s.state == _MSpanManual { + if s == nil || s.state == mSpanManual { // If s is nil, the virtual address has never been part of the heap. // This pointer may be to some mmap'd region, so we allow it. // Pointers into stacks are also ok, the runtime manages these explicitly. @@ -611,7 +611,7 @@ func bulkBarrierPreWrite(dst, src, size uintptr) { } } return - } else if s.state != _MSpanInUse || dst < s.base() || s.limit <= dst { + } else if s.state != mSpanInUse || dst < s.base() || s.limit <= dst { // dst was heap memory at some point, but isn't now. // It can't be a global. It must be either our stack, // or in the case of direct channel sends, it could be @@ -1911,6 +1911,20 @@ Run: return totalBits } +// materializeGCProg allocates space for the (1-bit) pointer bitmask +// for an object of size ptrdata. Then it fills that space with the +// pointer bitmask specified by the program prog. +// The bitmask starts at s.startAddr. +// The result must be deallocated with dematerializeGCProg. +func materializeGCProg(ptrdata uintptr, prog *byte) *mspan { + s := mheap_.allocManual((ptrdata/(8*sys.PtrSize)+pageSize-1)/pageSize, &memstats.gc_sys) + runGCProg(addb(prog, 4), nil, (*byte)(unsafe.Pointer(s.startAddr)), 1) + return s +} +func dematerializeGCProg(s *mspan) { + mheap_.freeManual(s, &memstats.gc_sys) +} + func dumpGCProg(p *byte) { nptr := 0 for { @@ -1980,7 +1994,9 @@ func reflect_gcbits(x interface{}) []byte { return ret } -// Returns GC type info for object p for testing. +// Returns GC type info for the pointer stored in ep for testing. +// If ep points to the stack, only static live information will be returned +// (i.e. not for objects which are only dynamically live stack objects). func getgcmask(ep interface{}) (mask []byte) { e := *efaceOf(&ep) p := e.data @@ -2037,7 +2053,7 @@ func getgcmask(ep interface{}) (mask []byte) { _g_ := getg() gentraceback(_g_.m.curg.sched.pc, _g_.m.curg.sched.sp, 0, _g_.m.curg, 0, nil, 1000, getgcmaskcb, noescape(unsafe.Pointer(&frame)), 0) if frame.fn.valid() { - locals, _ := getStackMap(&frame, nil, false) + locals, _, _ := getStackMap(&frame, nil, false) if locals.n == 0 { return } diff --git a/src/runtime/mcache.go b/src/runtime/mcache.go index d0b007f915..e20e92cdf4 100644 --- a/src/runtime/mcache.go +++ b/src/runtime/mcache.go @@ -4,7 +4,10 @@ package runtime -import "unsafe" +import ( + "runtime/internal/atomic" + "unsafe" +) // Per-thread (in Go, per-P) cache for small objects. // No locking needed because it is per-thread (per-P). @@ -42,6 +45,12 @@ type mcache struct { local_largefree uintptr // bytes freed for large objects (>maxsmallsize) local_nlargefree uintptr // number of frees for large objects (>maxsmallsize) local_nsmallfree [_NumSizeClasses]uintptr // number of frees for small objects (<=maxsmallsize) + + // flushGen indicates the sweepgen during which this mcache + // was last flushed. If flushGen != mheap_.sweepgen, the spans + // in this mcache are stale and need to the flushed so they + // can be swept. This is done in acquirep. + flushGen uint32 } // A gclink is a node in a linked list of blocks, like mlink, @@ -76,6 +85,7 @@ var emptymspan mspan func allocmcache() *mcache { lock(&mheap_.lock) c := (*mcache)(mheap_.cachealloc.alloc()) + c.flushGen = mheap_.sweepgen unlock(&mheap_.lock) for i := range c.alloc { c.alloc[i] = &emptymspan @@ -101,21 +111,24 @@ func freemcache(c *mcache) { }) } -// Gets a span that has a free object in it and assigns it -// to be the cached span for the given sizeclass. Returns this span. +// refill acquires a new span of span class spc for c. This span will +// have at least one free object. The current span in c must be full. +// +// Must run in a non-preemptible context since otherwise the owner of +// c could change. func (c *mcache) refill(spc spanClass) { - _g_ := getg() - - _g_.m.locks++ // Return the current cached span to the central lists. s := c.alloc[spc] if uintptr(s.allocCount) != s.nelems { throw("refill of span with free space remaining") } - if s != &emptymspan { - s.incache = false + // Mark this span as no longer cached. + if s.sweepgen != mheap_.sweepgen+3 { + throw("bad sweepgen in refill") + } + atomic.Store(&s.sweepgen, mheap_.sweepgen) } // Get a new cached span from the central lists. @@ -128,8 +141,11 @@ func (c *mcache) refill(spc spanClass) { throw("span has no free space") } + // Indicate that this span is cached and prevent asynchronous + // sweeping in the next sweep phase. + s.sweepgen = mheap_.sweepgen + 3 + c.alloc[spc] = s - _g_.m.locks-- } func (c *mcache) releaseAll() { @@ -144,3 +160,26 @@ func (c *mcache) releaseAll() { c.tiny = 0 c.tinyoffset = 0 } + +// prepareForSweep flushes c if the system has entered a new sweep phase +// since c was populated. This must happen between the sweep phase +// starting and the first allocation from c. +func (c *mcache) prepareForSweep() { + // Alternatively, instead of making sure we do this on every P + // between starting the world and allocating on that P, we + // could leave allocate-black on, allow allocation to continue + // as usual, use a ragged barrier at the beginning of sweep to + // ensure all cached spans are swept, and then disable + // allocate-black. However, with this approach it's difficult + // to avoid spilling mark bits into the *next* GC cycle. + sg := mheap_.sweepgen + if c.flushGen == sg { + return + } else if c.flushGen != sg-2 { + println("bad flushGen", c.flushGen, "in prepareForSweep; sweepgen", sg) + throw("bad flushGen") + } + c.releaseAll() + stackcache_clear(c) + atomic.Store(&c.flushGen, mheap_.sweepgen) // Synchronizes with gcStart +} diff --git a/src/runtime/mcentral.go b/src/runtime/mcentral.go index c1e0b472bc..9ca8e5d222 100644 --- a/src/runtime/mcentral.go +++ b/src/runtime/mcentral.go @@ -135,7 +135,6 @@ havespan: // heap_live changed. gcController.revise() } - s.incache = true freeByteBase := s.freeindex &^ (64 - 1) whichByte := freeByteBase / 8 // Init alloc bits cache. @@ -150,28 +149,54 @@ havespan: // Return span from an MCache. func (c *mcentral) uncacheSpan(s *mspan) { - lock(&c.lock) - - s.incache = false - if s.allocCount == 0 { throw("uncaching span but s.allocCount == 0") } cap := int32((s.npages << _PageShift) / s.elemsize) n := cap - int32(s.allocCount) + + // cacheSpan updated alloc assuming all objects on s were + // going to be allocated. Adjust for any that weren't. We must + // do this before potentially sweeping the span. if n > 0 { + atomic.Xadd64(&c.nmalloc, -int64(n)) + } + + sg := mheap_.sweepgen + stale := s.sweepgen == sg+1 + if stale { + // Span was cached before sweep began. It's our + // responsibility to sweep it. + // + // Set sweepgen to indicate it's not cached but needs + // sweeping. sweep will set s.sweepgen to indicate s + // is swept. + s.sweepgen = sg - 1 + s.sweep(true) + // sweep may have freed objects, so recompute n. + n = cap - int32(s.allocCount) + } else { + // Indicate that s is no longer cached. + s.sweepgen = sg + } + + if n > 0 { + lock(&c.lock) c.empty.remove(s) c.nonempty.insert(s) - // mCentral_CacheSpan conservatively counted - // unallocated slots in heap_live. Undo this. - atomic.Xadd64(&memstats.heap_live, -int64(n)*int64(s.elemsize)) - // cacheSpan updated alloc assuming all objects on s - // were going to be allocated. Adjust for any that - // weren't. - atomic.Xadd64(&c.nmalloc, -int64(n)) + if !stale { + // mCentral_CacheSpan conservatively counted + // unallocated slots in heap_live. Undo this. + // + // If this span was cached before sweep, then + // heap_live was totally recomputed since + // caching this span, so we don't do this for + // stale spans. + atomic.Xadd64(&memstats.heap_live, -int64(n)*int64(s.elemsize)) + } + unlock(&c.lock) } - unlock(&c.lock) } // freeSpan updates c and s after sweeping s. @@ -183,13 +208,13 @@ func (c *mcentral) uncacheSpan(s *mspan) { // If preserve=true, it does not move s (the caller // must take care of it). func (c *mcentral) freeSpan(s *mspan, preserve bool, wasempty bool) bool { - if s.incache { + if sg := mheap_.sweepgen; s.sweepgen == sg+1 || s.sweepgen == sg+3 { throw("freeSpan given cached span") } s.needzero = 1 if preserve { - // preserve is set only when called from MCentral_CacheSpan above, + // preserve is set only when called from (un)cacheSpan above, // the span must be in the empty list. if !s.inList() { throw("can't preserve unlinked span") diff --git a/src/runtime/mem_darwin.go b/src/runtime/mem_aix.go index 75c59f9cdd..f11f0aba52 100644 --- a/src/runtime/mem_darwin.go +++ b/src/runtime/mem_aix.go @@ -1,26 +1,36 @@ -// Copyright 2010 The Go Authors. All rights reserved. +// Copyright 2018 The Go Authors. All rights reserved. // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. package runtime -import "unsafe" +import ( + "unsafe" +) -// Don't split the stack as this function may be invoked without a valid G, -// which prevents us from allocating more stack. +// Don't split the stack as this method may be invoked without a valid G, which +// prevents us from allocating more stack. //go:nosplit func sysAlloc(n uintptr, sysStat *uint64) unsafe.Pointer { - v, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_PRIVATE, -1, 0) + p, err := mmap(nil, n, _PROT_READ|_PROT_WRITE, _MAP_ANONYMOUS|_MAP_PRIVATE, -1, 0) if err != 0 { + if err == _EACCES { + print("runtime: mmap: access denied\n") + exit(2) + } + if err == _EAGAIN { + print("runtime: mmap: too much locked memory (check 'ulimit -l').\n") + exit(2) + } + //println("sysAlloc failed: ", err) return nil } mSysStatInc(sysStat, n) - return v + return p } func sysUnused(v unsafe.Pointer, n uintptr) { - // Linux's MADV_DONTNEED is like BSD's MADV_FREE. - madvise(v, n, _MADV_FREE) + madvise(v, n, _MADV_DONTNEED) } func sysUsed(v unsafe.Pointer, n uintptr) { @@ -32,27 +42,29 @@ func sysUsed(v unsafe.Pointer, n uintptr) { func sysFree(v unsafe.Pointer, n uintptr, sysStat *uint64) { mSysStatDec(sysStat, n) munmap(v, n) + } func sysFault(v unsafe.Pointer, n uintptr) { - mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE|_MAP_FIXED, -1, 0) + mmap(v, n, _PROT_NONE, _MAP_ANONYMOUS|_MAP_PRIVATE|_MAP_FIXED, -1, 0) } func sysReserve(v unsafe.Pointer, n uintptr) unsafe.Pointer { - p, err := mmap(v, n, _PROT_NONE, _MAP_ANON|_MAP_PRIVATE, -1, 0) + p, err := mmap(v, n, _PROT_NONE, _MAP_ANONYMOUS|_MAP_PRIVATE, -1, 0) if err != 0 { return nil } return p } -const ( - _ENOMEM = 12 -) - func sysMap(v unsafe.Pointer, n uintptr, sysStat *uint64) { mSysStatInc(sysStat, n) - p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANON|_MAP_FIXED|_MAP_PRIVATE, -1, 0) + + // AIX does not allow mapping a range that is already mapped. + // So always unmap first even if it is already unmapped. + munmap(v, n) + p, err := mmap(v, n, _PROT_READ|_PROT_WRITE, _MAP_ANONYMOUS|_MAP_FIXED|_MAP_PRIVATE, -1, 0) + if err == _ENOMEM { throw("runtime: out of memory") } diff --git a/src/runtime/mem_bsd.go b/src/runtime/mem_bsd.go index cc70e806ea..13065b61d4 100644 --- a/src/runtime/mem_bsd.go +++ b/src/runtime/mem_bsd.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build dragonfly freebsd nacl netbsd openbsd solaris +// +build darwin dragonfly freebsd nacl netbsd openbsd solaris package runtime diff --git a/src/runtime/mem_linux.go b/src/runtime/mem_linux.go index 7aa48170a1..845f72ded2 100644 --- a/src/runtime/mem_linux.go +++ b/src/runtime/mem_linux.go @@ -5,6 +5,7 @@ package runtime import ( + "runtime/internal/atomic" "runtime/internal/sys" "unsafe" ) @@ -34,10 +35,12 @@ func sysAlloc(n uintptr, sysStat *uint64) unsafe.Pointer { return p } +var adviseUnused = uint32(_MADV_FREE) + func sysUnused(v unsafe.Pointer, n uintptr) { // By default, Linux's "transparent huge page" support will // merge pages into a huge page if there's even a single - // present regular page, undoing the effects of the DONTNEED + // present regular page, undoing the effects of madvise(adviseUnused) // below. On amd64, that means khugepaged can turn a single // 4KB page to 2MB, bloating the process's RSS by as much as // 512X. (See issue #8832 and Linux kernel bug @@ -102,7 +105,13 @@ func sysUnused(v unsafe.Pointer, n uintptr) { throw("unaligned sysUnused") } - madvise(v, n, _MADV_DONTNEED) + advise := atomic.Load(&adviseUnused) + if errno := madvise(v, n, int32(advise)); advise == _MADV_FREE && errno != 0 { + // MADV_FREE was added in Linux 4.5. Fall back to MADV_DONTNEED if it is + // not supported. + atomic.Store(&adviseUnused, _MADV_DONTNEED) + madvise(v, n, _MADV_DONTNEED) + } } func sysUsed(v unsafe.Pointer, n uintptr) { diff --git a/src/runtime/memmove_amd64p32.s b/src/runtime/memmove_amd64p32.s index 8e9fdd14c5..114077311c 100644 --- a/src/runtime/memmove_amd64p32.s +++ b/src/runtime/memmove_amd64p32.s @@ -34,7 +34,7 @@ back: ADDL BX, DI ADDL BX, SI STD - + MOVL BX, CX SHRL $2, CX ANDL $3, BX diff --git a/src/runtime/memmove_arm.s b/src/runtime/memmove_arm.s index 324b21bf7a..8352fb7860 100644 --- a/src/runtime/memmove_arm.s +++ b/src/runtime/memmove_arm.s @@ -138,7 +138,7 @@ _f32loop: CMP TMP, TS BHS _f4tail - MOVM.IA.W (FROM), [R1-R8] + MOVM.IA.W (FROM), [R1-R8] MOVM.IA.W [R1-R8], (TS) B _f32loop diff --git a/src/runtime/memmove_plan9_386.s b/src/runtime/memmove_plan9_386.s index 7ff01940a2..65dec93f6b 100644 --- a/src/runtime/memmove_plan9_386.s +++ b/src/runtime/memmove_plan9_386.s @@ -56,7 +56,7 @@ tail: /* * forward copy loop */ -forward: +forward: MOVL BX, CX SHRL $2, CX ANDL $3, BX diff --git a/src/runtime/memmove_plan9_amd64.s b/src/runtime/memmove_plan9_amd64.s index f18b59f3d2..b729c7c0e7 100644 --- a/src/runtime/memmove_plan9_amd64.s +++ b/src/runtime/memmove_plan9_amd64.s @@ -73,7 +73,7 @@ back: ADDQ BX, CX CMPQ CX, DI JLS forward - + /* * whole thing backwards has * adjusted addresses diff --git a/src/runtime/mgc.go b/src/runtime/mgc.go index c95b5ed37f..9dfee5a4dc 100644 --- a/src/runtime/mgc.go +++ b/src/runtime/mgc.go @@ -28,8 +28,7 @@ // b. Sweep any unswept spans. There will only be unswept spans if // this GC cycle was forced before the expected time. // -// 2. GC performs the "mark 1" sub-phase. In this sub-phase, Ps are -// allowed to locally cache parts of the work queue. +// 2. GC performs the mark phase. // // a. Prepare for the mark phase by setting gcphase to _GCmark // (from _GCoff), enabling the write barrier, enabling mutator @@ -54,28 +53,21 @@ // object to black and shading all pointers found in the object // (which in turn may add those pointers to the work queue). // -// 3. Once the global work queue is empty (but local work queue caches -// may still contain work), GC performs the "mark 2" sub-phase. +// e. Because GC work is spread across local caches, GC uses a +// distributed termination algorithm to detect when there are no +// more root marking jobs or grey objects (see gcMarkDone). At this +// point, GC transitions to mark termination. // -// a. GC stops all workers, disables local work queue caches, -// flushes each P's local work queue cache to the global work queue -// cache, and reenables workers. -// -// b. GC again drains the work queue, as in 2d above. -// -// 4. Once the work queue is empty, GC performs mark termination. +// 3. GC performs mark termination. // // a. Stop the world. // // b. Set gcphase to _GCmarktermination, and disable workers and // assists. // -// c. Drain any remaining work from the work queue (typically there -// will be none). +// c. Perform housekeeping like flushing mcaches. // -// d. Perform other housekeeping like flushing mcaches. -// -// 5. GC performs the sweep phase. +// 4. GC performs the sweep phase. // // a. Prepare for the sweep phase by setting gcphase to _GCoff, // setting up sweep state and disabling the write barrier. @@ -86,7 +78,7 @@ // c. GC does concurrent sweeping in the background and in response // to allocation. See description below. // -// 6. When sufficient allocation has taken place, replay the sequence +// 5. When sufficient allocation has taken place, replay the sequence // starting with 1 above. See discussion of GC rate below. // Concurrent sweep. @@ -261,21 +253,6 @@ var writeBarrier struct { // gcphase == _GCmark. var gcBlackenEnabled uint32 -// gcBlackenPromptly indicates that optimizations that may -// hide work from the global work queue should be disabled. -// -// If gcBlackenPromptly is true, per-P gcWork caches should -// be flushed immediately and new objects should be allocated black. -// -// There is a tension between allocating objects white and -// allocating them black. If white and the objects die before being -// marked they can be collected during this GC cycle. On the other -// hand allocating them black will reduce _GCmarktermination latency -// since more work is done in the mark phase. This tension is resolved -// by allocating white until the mark phase is approaching its end and -// then allocating black for the remainder of the mark phase. -var gcBlackenPromptly bool - const ( _GCoff = iota // GC not running; sweeping in background, write barrier disabled _GCmark // GC marking roots and workbufs: allocate black, write barrier ENABLED @@ -478,6 +455,12 @@ func (c *gcControllerState) startCycle() { c.fractionalUtilizationGoal = 0 } + // In STW mode, we just want dedicated workers. + if debug.gcstoptheworld > 0 { + c.dedicatedMarkWorkersNeeded = int64(gomaxprocs) + c.fractionalUtilizationGoal = 0 + } + // Clear per-P state for _, p := range allp { p.gcAssistTime = 0 @@ -955,32 +938,15 @@ var work struct { markrootNext uint32 // next markroot job markrootJobs uint32 // number of markroot jobs - nproc uint32 - tstart int64 - nwait uint32 - ndone uint32 - alldone note - - // helperDrainBlock indicates that GC mark termination helpers - // should pass gcDrainBlock to gcDrain to block in the - // getfull() barrier. Otherwise, they should pass gcDrainNoBlock. - // - // TODO: This is a temporary fallback to work around races - // that cause early mark termination. - helperDrainBlock bool + nproc uint32 + tstart int64 + nwait uint32 + ndone uint32 // Number of roots of various root types. Set by gcMarkRootPrepare. nFlushCacheRoots int nDataRoots, nBSSRoots, nSpanRoots, nStackRoots int - // markrootDone indicates that roots have been marked at least - // once during the current GC cycle. This is checked by root - // marking operations that have to happen only during the - // first root marking pass, whether that's during the - // concurrent mark phase in current GC or mark termination in - // STW GC. - markrootDone bool - // Each type of GC state transition is protected by a lock. // Since multiple threads can simultaneously detect the state // transition condition, any thread that detects a transition @@ -996,8 +962,7 @@ var work struct { // startSema protects the transition from "off" to mark or // mark termination. startSema uint32 - // markDoneSema protects transitions from mark 1 to mark 2 and - // from mark 2 to mark termination. + // markDoneSema protects transitions from mark to mark termination. markDoneSema uint32 bgMarkReady note // signal background mark worker has started @@ -1087,7 +1052,7 @@ func GC() { // We're now in sweep N or later. Trigger GC cycle N+1, which // will first finish sweep N if necessary and then enter sweep // termination N+1. - gcStart(gcBackgroundMode, gcTrigger{kind: gcTriggerCycle, n: n + 1}) + gcStart(gcTrigger{kind: gcTriggerCycle, n: n + 1}) // Wait for mark termination N+1 to complete. gcWaitOnMark(n + 1) @@ -1225,13 +1190,13 @@ func (t gcTrigger) test() bool { return true } -// gcStart transitions the GC from _GCoff to _GCmark (if -// !mode.stwMark) or _GCmarktermination (if mode.stwMark) by -// performing sweep termination and GC initialization. +// gcStart starts the GC. It transitions from _GCoff to _GCmark (if +// debug.gcstoptheworld == 0) or performs all of GC (if +// debug.gcstoptheworld != 0). // // This may return without performing this transition in some cases, // such as when called on a system stack or with locks held. -func gcStart(mode gcMode, trigger gcTrigger) { +func gcStart(trigger gcTrigger) { // Since this is called from malloc and malloc is called in // the guts of a number of libraries that might be holding // locks, don't attempt to start GC in non-preemptible or @@ -1274,12 +1239,11 @@ func gcStart(mode gcMode, trigger gcTrigger) { // We do this after re-checking the transition condition so // that multiple goroutines that detect the heap trigger don't // start multiple STW GCs. - if mode == gcBackgroundMode { - if debug.gcstoptheworld == 1 { - mode = gcForceMode - } else if debug.gcstoptheworld == 2 { - mode = gcForceBlockMode - } + mode := gcBackgroundMode + if debug.gcstoptheworld == 1 { + mode = gcForceMode + } else if debug.gcstoptheworld == 2 { + mode = gcForceBlockMode } // Ok, we're doing it! Stop everybody else @@ -1289,10 +1253,16 @@ func gcStart(mode gcMode, trigger gcTrigger) { traceGCStart() } - if mode == gcBackgroundMode { - gcBgMarkStartWorkers() + // Check that all Ps have finished deferred mcache flushes. + for _, p := range allp { + if fg := atomic.Load(&p.mcache.flushGen); fg != mheap_.sweepgen { + println("runtime: p", p.id, "flushGen", fg, "!= sweepgen", mheap_.sweepgen) + throw("p mcache not flushed") + } } + gcBgMarkStartWorkers() + gcResetMarkState() work.stwprocs, work.maxprocs = gomaxprocs, gomaxprocs @@ -1321,199 +1291,192 @@ func gcStart(mode gcMode, trigger gcTrigger) { clearpools() work.cycles++ - if mode == gcBackgroundMode { // Do as much work concurrently as possible - gcController.startCycle() - work.heapGoal = memstats.next_gc - // Enter concurrent mark phase and enable - // write barriers. - // - // Because the world is stopped, all Ps will - // observe that write barriers are enabled by - // the time we start the world and begin - // scanning. - // - // Write barriers must be enabled before assists are - // enabled because they must be enabled before - // any non-leaf heap objects are marked. Since - // allocations are blocked until assists can - // happen, we want enable assists as early as - // possible. - setGCPhase(_GCmark) + gcController.startCycle() + work.heapGoal = memstats.next_gc - gcBgMarkPrepare() // Must happen before assist enable. - gcMarkRootPrepare() + // In STW mode, disable scheduling of user Gs. This may also + // disable scheduling of this goroutine, so it may block as + // soon as we start the world again. + if mode != gcBackgroundMode { + schedEnableUser(false) + } - // Mark all active tinyalloc blocks. Since we're - // allocating from these, they need to be black like - // other allocations. The alternative is to blacken - // the tiny block on every allocation from it, which - // would slow down the tiny allocator. - gcMarkTinyAllocs() + // Enter concurrent mark phase and enable + // write barriers. + // + // Because the world is stopped, all Ps will + // observe that write barriers are enabled by + // the time we start the world and begin + // scanning. + // + // Write barriers must be enabled before assists are + // enabled because they must be enabled before + // any non-leaf heap objects are marked. Since + // allocations are blocked until assists can + // happen, we want enable assists as early as + // possible. + setGCPhase(_GCmark) - // At this point all Ps have enabled the write - // barrier, thus maintaining the no white to - // black invariant. Enable mutator assists to - // put back-pressure on fast allocating - // mutators. - atomic.Store(&gcBlackenEnabled, 1) + gcBgMarkPrepare() // Must happen before assist enable. + gcMarkRootPrepare() - // Assists and workers can start the moment we start - // the world. - gcController.markStartTime = now + // Mark all active tinyalloc blocks. Since we're + // allocating from these, they need to be black like + // other allocations. The alternative is to blacken + // the tiny block on every allocation from it, which + // would slow down the tiny allocator. + gcMarkTinyAllocs() - // Concurrent mark. - systemstack(func() { - now = startTheWorldWithSema(trace.enabled) - }) + // At this point all Ps have enabled the write + // barrier, thus maintaining the no white to + // black invariant. Enable mutator assists to + // put back-pressure on fast allocating + // mutators. + atomic.Store(&gcBlackenEnabled, 1) + + // Assists and workers can start the moment we start + // the world. + gcController.markStartTime = now + + // Concurrent mark. + systemstack(func() { + now = startTheWorldWithSema(trace.enabled) work.pauseNS += now - work.pauseStart work.tMark = now - } else { - if trace.enabled { - // Switch to mark termination STW. - traceGCSTWDone() - traceGCSTWStart(0) - } - t := nanotime() - work.tMark, work.tMarkTerm = t, t - work.heapGoal = work.heap0 - - // Perform mark termination. This will restart the world. - gcMarkTermination(memstats.triggerRatio) + }) + // In STW mode, we could block the instant systemstack + // returns, so don't do anything important here. Make sure we + // block rather than returning to user code. + if mode != gcBackgroundMode { + Gosched() } semrelease(&work.startSema) } -// gcMarkDone transitions the GC from mark 1 to mark 2 and from mark 2 -// to mark termination. +// gcMarkDoneFlushed counts the number of P's with flushed work. // -// This should be called when all mark work has been drained. In mark -// 1, this includes all root marking jobs, global work buffers, and -// active work buffers in assists and background workers; however, -// work may still be cached in per-P work buffers. In mark 2, per-P -// caches are disabled. +// Ideally this would be a captured local in gcMarkDone, but forEachP +// escapes its callback closure, so it can't capture anything. +// +// This is protected by markDoneSema. +var gcMarkDoneFlushed uint32 + +// gcMarkDone transitions the GC from mark to mark termination if all +// reachable objects have been marked (that is, there are no grey +// objects and can be no more in the future). Otherwise, it flushes +// all local work to the global queues where it can be discovered by +// other workers. +// +// This should be called when all local mark work has been drained and +// there are no remaining workers. Specifically, when +// +// work.nwait == work.nproc && !gcMarkWorkAvailable(p) // // The calling context must be preemptible. // -// Note that it is explicitly okay to have write barriers in this -// function because completion of concurrent mark is best-effort -// anyway. Any work created by write barriers here will be cleaned up -// by mark termination. +// Flushing local work is important because idle Ps may have local +// work queued. This is the only way to make that work visible and +// drive GC to completion. +// +// It is explicitly okay to have write barriers in this function. If +// it does transition to mark termination, then all reachable objects +// have been marked, so the write barrier cannot shade any more +// objects. func gcMarkDone() { -top: + // Ensure only one thread is running the ragged barrier at a + // time. semacquire(&work.markDoneSema) +top: // Re-check transition condition under transition lock. + // + // It's critical that this checks the global work queues are + // empty before performing the ragged barrier. Otherwise, + // there could be global work that a P could take after the P + // has passed the ragged barrier. if !(gcphase == _GCmark && work.nwait == work.nproc && !gcMarkWorkAvailable(nil)) { semrelease(&work.markDoneSema) return } - // Disallow starting new workers so that any remaining workers - // in the current mark phase will drain out. - // - // TODO(austin): Should dedicated workers keep an eye on this - // and exit gcDrain promptly? - atomic.Xaddint64(&gcController.dedicatedMarkWorkersNeeded, -0xffffffff) - prevFractionalGoal := gcController.fractionalUtilizationGoal - gcController.fractionalUtilizationGoal = 0 - - if !gcBlackenPromptly { - // Transition from mark 1 to mark 2. - // - // The global work list is empty, but there can still be work - // sitting in the per-P work caches. - // Flush and disable work caches. - - // Disallow caching workbufs and indicate that we're in mark 2. - gcBlackenPromptly = true - - // Prevent completion of mark 2 until we've flushed - // cached workbufs. - atomic.Xadd(&work.nwait, -1) - - // GC is set up for mark 2. Let Gs blocked on the - // transition lock go while we flush caches. - semrelease(&work.markDoneSema) - - systemstack(func() { - // Flush all currently cached workbufs and - // ensure all Ps see gcBlackenPromptly. This - // also blocks until any remaining mark 1 - // workers have exited their loop so we can - // start new mark 2 workers. - forEachP(func(_p_ *p) { - wbBufFlush1(_p_) - _p_.gcw.dispose() - }) + // Flush all local buffers and collect flushedWork flags. + gcMarkDoneFlushed = 0 + systemstack(func() { + forEachP(func(_p_ *p) { + // Flush the write barrier buffer, since this may add + // work to the gcWork. + wbBufFlush1(_p_) + // Flush the gcWork, since this may create global work + // and set the flushedWork flag. + // + // TODO(austin): Break up these workbufs to + // better distribute work. + _p_.gcw.dispose() + // Collect the flushedWork flag. + if _p_.gcw.flushedWork { + atomic.Xadd(&gcMarkDoneFlushed, 1) + _p_.gcw.flushedWork = false + } }) + }) - // Check that roots are marked. We should be able to - // do this before the forEachP, but based on issue - // #16083 there may be a (harmless) race where we can - // enter mark 2 while some workers are still scanning - // stacks. The forEachP ensures these scans are done. - // - // TODO(austin): Figure out the race and fix this - // properly. - gcMarkRootCheck() - - // Now we can start up mark 2 workers. - atomic.Xaddint64(&gcController.dedicatedMarkWorkersNeeded, 0xffffffff) - gcController.fractionalUtilizationGoal = prevFractionalGoal + if gcMarkDoneFlushed != 0 { + // More grey objects were discovered since the + // previous termination check, so there may be more + // work to do. Keep going. It's possible the + // transition condition became true again during the + // ragged barrier, so re-check it. + goto top + } - incnwait := atomic.Xadd(&work.nwait, +1) - if incnwait == work.nproc && !gcMarkWorkAvailable(nil) { - // This loop will make progress because - // gcBlackenPromptly is now true, so it won't - // take this same "if" branch. - goto top - } - } else { - // Transition to mark termination. - now := nanotime() - work.tMarkTerm = now - work.pauseStart = now - getg().m.preemptoff = "gcing" - if trace.enabled { - traceGCSTWStart(0) - } - systemstack(stopTheWorldWithSema) - // The gcphase is _GCmark, it will transition to _GCmarktermination - // below. The important thing is that the wb remains active until - // all marking is complete. This includes writes made by the GC. + // There was no global work, no local work, and no Ps + // communicated work since we took markDoneSema. Therefore + // there are no grey objects and no more objects can be + // shaded. Transition to mark termination. + now := nanotime() + work.tMarkTerm = now + work.pauseStart = now + getg().m.preemptoff = "gcing" + if trace.enabled { + traceGCSTWStart(0) + } + systemstack(stopTheWorldWithSema) + // The gcphase is _GCmark, it will transition to _GCmarktermination + // below. The important thing is that the wb remains active until + // all marking is complete. This includes writes made by the GC. - // Record that one root marking pass has completed. - work.markrootDone = true + // Disable assists and background workers. We must do + // this before waking blocked assists. + atomic.Store(&gcBlackenEnabled, 0) - // Disable assists and background workers. We must do - // this before waking blocked assists. - atomic.Store(&gcBlackenEnabled, 0) + // Wake all blocked assists. These will run when we + // start the world again. + gcWakeAllAssists() - // Wake all blocked assists. These will run when we - // start the world again. - gcWakeAllAssists() + // Likewise, release the transition lock. Blocked + // workers and assists will run when we start the + // world again. + semrelease(&work.markDoneSema) - // Likewise, release the transition lock. Blocked - // workers and assists will run when we start the - // world again. - semrelease(&work.markDoneSema) + // In STW mode, re-enable user goroutines. These will be + // queued to run after we start the world. + schedEnableUser(true) - // endCycle depends on all gcWork cache stats being - // flushed. This is ensured by mark 2. - nextTriggerRatio := gcController.endCycle() + // endCycle depends on all gcWork cache stats being flushed. + // The termination algorithm above ensured that up to + // allocations since the ragged barrier. + nextTriggerRatio := gcController.endCycle() - // Perform mark termination. This will restart the world. - gcMarkTermination(nextTriggerRatio) - } + // Perform mark termination. This will restart the world. + gcMarkTermination(nextTriggerRatio) } func gcMarkTermination(nextTriggerRatio float64) { // World is stopped. // Start marktermination which includes enabling the write barrier. atomic.Store(&gcBlackenEnabled, 0) - gcBlackenPromptly = false setGCPhase(_GCmarktermination) work.heap1 = memstats.heap_live @@ -1546,35 +1509,22 @@ func gcMarkTermination(nextTriggerRatio float64) { systemstack(func() { work.heap2 = work.bytesMarked if debug.gccheckmark > 0 { - // Run a full stop-the-world mark using checkmark bits, - // to check that we didn't forget to mark anything during - // the concurrent mark process. + // Run a full non-parallel, stop-the-world + // mark using checkmark bits, to check that we + // didn't forget to mark anything during the + // concurrent mark process. gcResetMarkState() initCheckmarks() - gcMark(startTime) + gcw := &getg().m.p.ptr().gcw + gcDrain(gcw, 0) + wbBufFlush1(getg().m.p.ptr()) + gcw.dispose() clearCheckmarks() } // marking is complete so we can turn the write barrier off setGCPhase(_GCoff) gcSweep(work.mode) - - if debug.gctrace > 1 { - startTime = nanotime() - // The g stacks have been scanned so - // they have gcscanvalid==true and gcworkdone==true. - // Reset these so that all stacks will be rescanned. - gcResetMarkState() - finishsweep_m() - - // Still in STW but gcphase is _GCoff, reset to _GCmarktermination - // At this point all objects will be found during the gcMark which - // does a complete STW mark and object scan. - setGCPhase(_GCmarktermination) - gcMark(startTime) - setGCPhase(_GCoff) // marking is done, turn off wb. - gcSweep(work.mode) - } }) _g_.m.traceback = 0 @@ -1652,6 +1602,16 @@ func gcMarkTermination(nextTriggerRatio float64) { // Free stack spans. This must be done between GC cycles. systemstack(freeStackSpans) + // Ensure all mcaches are flushed. Each P will flush its own + // mcache before allocating, but idle Ps may not. Since this + // is necessary to sweep all spans, we need to ensure all + // mcaches are flushed before we start the next GC cycle. + systemstack(func() { + forEachP(func(_p_ *p) { + _p_.mcache.prepareForSweep() + }) + }) + // Print gctrace before dropping worldsema. As soon as we drop // worldsema another cycle could start and smash the stats // we're trying to print. @@ -1852,7 +1812,7 @@ func gcBgMarkWorker(_p_ *p) { } // Go back to draining, this time // without preemption. - gcDrain(&_p_.gcw, gcDrainNoBlock|gcDrainFlushBgCredit) + gcDrain(&_p_.gcw, gcDrainFlushBgCredit) case gcMarkWorkerFractionalMode: gcDrain(&_p_.gcw, gcDrainFractional|gcDrainUntilPreempt|gcDrainFlushBgCredit) case gcMarkWorkerIdleMode: @@ -1861,16 +1821,6 @@ func gcBgMarkWorker(_p_ *p) { casgstatus(gp, _Gwaiting, _Grunning) }) - // If we are nearing the end of mark, dispose - // of the cache promptly. We must do this - // before signaling that we're no longer - // working so that other workers can't observe - // no workers and no work while we have this - // cached, and before we compute done. - if gcBlackenPromptly { - _p_.gcw.dispose() - } - // Account for time. duration := nanotime() - startTime switch _p_.gcMarkWorkerMode { @@ -1947,50 +1897,11 @@ func gcMark(start_time int64) { } work.tstart = start_time - // Queue root marking jobs. - gcMarkRootPrepare() - - work.nwait = 0 - work.ndone = 0 - work.nproc = uint32(gcprocs()) - - if work.full == 0 && work.nDataRoots+work.nBSSRoots+work.nSpanRoots+work.nStackRoots == 0 { - // There's no work on the work queue and no root jobs - // that can produce work, so don't bother entering the - // getfull() barrier. - // - // This will be the situation the vast majority of the - // time after concurrent mark. However, we still need - // a fallback for STW GC and because there are some - // known races that occasionally leave work around for - // mark termination. - // - // We're still hedging our bets here: if we do - // accidentally produce some work, we'll still process - // it, just not necessarily in parallel. - // - // TODO(austin): Fix the races and and remove - // work draining from mark termination so we don't - // need the fallback path. - work.helperDrainBlock = false - } else { - work.helperDrainBlock = true - } - - if work.nproc > 1 { - noteclear(&work.alldone) - helpgc(int32(work.nproc)) - } - - gchelperstart() - - gcw := &getg().m.p.ptr().gcw - if work.helperDrainBlock { - gcDrain(gcw, gcDrainBlock) - } else { - gcDrain(gcw, gcDrainNoBlock) + // Check that there's no marking work remaining. + if work.full != 0 || work.markrootNext < work.markrootJobs { + print("runtime: full=", hex(work.full), " next=", work.markrootNext, " jobs=", work.markrootJobs, " nDataRoots=", work.nDataRoots, " nBSSRoots=", work.nBSSRoots, " nSpanRoots=", work.nSpanRoots, " nStackRoots=", work.nStackRoots, "\n") + panic("non-empty mark queue after concurrent mark") } - gcw.dispose() if debug.gccheckmark > 0 { // This is expensive when there's a large number of @@ -2001,23 +1912,35 @@ func gcMark(start_time int64) { throw("work.full != 0") } - if work.nproc > 1 { - notesleep(&work.alldone) - } - - // Record that at least one root marking pass has completed. - work.markrootDone = true - - // Double-check that all gcWork caches are empty. This should - // be ensured by mark 2 before we enter mark termination. + // Clear out buffers and double-check that all gcWork caches + // are empty. This should be ensured by gcMarkDone before we + // enter mark termination. + // + // TODO: We could clear out buffers just before mark if this + // has a non-negligible impact on STW time. for _, p := range allp { + // The write barrier may have buffered pointers since + // the gcMarkDone barrier. However, since the barrier + // ensured all reachable objects were marked, all of + // these must be pointers to black objects. Hence we + // can just discard the write barrier buffer. + if debug.gccheckmark > 0 { + // For debugging, flush the buffer and make + // sure it really was all marked. + wbBufFlush1(p) + } else { + p.wbBuf.reset() + } + gcw := &p.gcw if !gcw.empty() { throw("P has cached GC work at end of mark termination") } - if gcw.scanWork != 0 || gcw.bytesMarked != 0 { - throw("P has unflushed stats at end of mark termination") - } + // There may still be cached empty buffers, which we + // need to flush since we're going to free them. Also, + // there may be non-zero stats because we allocated + // black after the gcMarkDone barrier. + gcw.dispose() } cachestats() @@ -2102,7 +2025,6 @@ func gcResetMarkState() { work.bytesMarked = 0 work.initialHeapLive = atomic.Load64(&memstats.heap_live) - work.markrootDone = false } // Hooks for other packages @@ -2149,48 +2071,6 @@ func clearpools() { unlock(&sched.deferlock) } -// gchelper runs mark termination tasks on Ps other than the P -// coordinating mark termination. -// -// The caller is responsible for ensuring that this has a P to run on, -// even though it's running during STW. Because of this, it's allowed -// to have write barriers. -// -//go:yeswritebarrierrec -func gchelper() { - _g_ := getg() - _g_.m.traceback = 2 - gchelperstart() - - // Parallel mark over GC roots and heap - if gcphase == _GCmarktermination { - gcw := &_g_.m.p.ptr().gcw - if work.helperDrainBlock { - gcDrain(gcw, gcDrainBlock) // blocks in getfull - } else { - gcDrain(gcw, gcDrainNoBlock) - } - gcw.dispose() - } - - nproc := atomic.Load(&work.nproc) // work.nproc can change right after we increment work.ndone - if atomic.Xadd(&work.ndone, +1) == nproc-1 { - notewakeup(&work.alldone) - } - _g_.m.traceback = 0 -} - -func gchelperstart() { - _g_ := getg() - - if _g_.m.helpgc < 0 || _g_.m.helpgc >= _MaxGcproc { - throw("gchelperstart: bad m->helpgc") - } - if _g_ != _g_.m.g0 { - throw("gchelper not running on g0 stack") - } -} - // Timing // itoaDiv formats val/(10**dec) into buf. diff --git a/src/runtime/mgcmark.go b/src/runtime/mgcmark.go index 69ff895512..d4dcfb6cb9 100644 --- a/src/runtime/mgcmark.go +++ b/src/runtime/mgcmark.go @@ -52,11 +52,7 @@ const ( // //go:nowritebarrier func gcMarkRootPrepare() { - if gcphase == _GCmarktermination { - work.nFlushCacheRoots = int(gomaxprocs) - } else { - work.nFlushCacheRoots = 0 - } + work.nFlushCacheRoots = 0 // Compute how many data and BSS root blocks there are. nBlocks := func(bytes uintptr) int { @@ -66,62 +62,41 @@ func gcMarkRootPrepare() { work.nDataRoots = 0 work.nBSSRoots = 0 - // Only scan globals once per cycle; preferably concurrently. - if !work.markrootDone { - for _, datap := range activeModules() { - nDataRoots := nBlocks(datap.edata - datap.data) - if nDataRoots > work.nDataRoots { - work.nDataRoots = nDataRoots - } + // Scan globals. + for _, datap := range activeModules() { + nDataRoots := nBlocks(datap.edata - datap.data) + if nDataRoots > work.nDataRoots { + work.nDataRoots = nDataRoots } + } - for _, datap := range activeModules() { - nBSSRoots := nBlocks(datap.ebss - datap.bss) - if nBSSRoots > work.nBSSRoots { - work.nBSSRoots = nBSSRoots - } + for _, datap := range activeModules() { + nBSSRoots := nBlocks(datap.ebss - datap.bss) + if nBSSRoots > work.nBSSRoots { + work.nBSSRoots = nBSSRoots } } - if !work.markrootDone { - // On the first markroot, we need to scan span roots. - // In concurrent GC, this happens during concurrent - // mark and we depend on addfinalizer to ensure the - // above invariants for objects that get finalizers - // after concurrent mark. In STW GC, this will happen - // during mark termination. - // - // We're only interested in scanning the in-use spans, - // which will all be swept at this point. More spans - // may be added to this list during concurrent GC, but - // we only care about spans that were allocated before - // this mark phase. - work.nSpanRoots = mheap_.sweepSpans[mheap_.sweepgen/2%2].numBlocks() - - // On the first markroot, we need to scan all Gs. Gs - // may be created after this point, but it's okay that - // we ignore them because they begin life without any - // roots, so there's nothing to scan, and any roots - // they create during the concurrent phase will be - // scanned during mark termination. During mark - // termination, allglen isn't changing, so we'll scan - // all Gs. - work.nStackRoots = int(atomic.Loaduintptr(&allglen)) - } else { - // We've already scanned span roots and kept the scan - // up-to-date during concurrent mark. - work.nSpanRoots = 0 - - // The hybrid barrier ensures that stacks can't - // contain pointers to unmarked objects, so on the - // second markroot, there's no need to scan stacks. - work.nStackRoots = 0 + // Scan span roots for finalizer specials. + // + // We depend on addfinalizer to mark objects that get + // finalizers after root marking. + // + // We're only interested in scanning the in-use spans, + // which will all be swept at this point. More spans + // may be added to this list during concurrent GC, but + // we only care about spans that were allocated before + // this mark phase. + work.nSpanRoots = mheap_.sweepSpans[mheap_.sweepgen/2%2].numBlocks() - if debug.gcrescanstacks > 0 { - // Scan stacks anyway for debugging. - work.nStackRoots = int(atomic.Loaduintptr(&allglen)) - } - } + // Scan stacks. + // + // Gs may be created after this point, but it's okay that we + // ignore them because they begin life without any roots, so + // there's nothing to scan, and any roots they create during + // the concurrent phase will be scanned during mark + // termination. + work.nStackRoots = int(atomic.Loaduintptr(&allglen)) work.markrootNext = 0 work.markrootJobs = uint32(fixedRootCount + work.nFlushCacheRoots + work.nDataRoots + work.nBSSRoots + work.nSpanRoots + work.nStackRoots) @@ -138,19 +113,10 @@ func gcMarkRootCheck() { lock(&allglock) // Check that stacks have been scanned. var gp *g - if gcphase == _GCmarktermination && debug.gcrescanstacks > 0 { - for i := 0; i < len(allgs); i++ { - gp = allgs[i] - if !(gp.gcscandone && gp.gcscanvalid) && readgstatus(gp) != _Gdead { - goto fail - } - } - } else { - for i := 0; i < work.nStackRoots; i++ { - gp = allgs[i] - if !gp.gcscandone { - goto fail - } + for i := 0; i < work.nStackRoots; i++ { + gp = allgs[i] + if !gp.gcscandone { + goto fail } } unlock(&allglock) @@ -201,24 +167,15 @@ func markroot(gcw *gcWork, i uint32) { } case i == fixedRootFinalizers: - // Only do this once per GC cycle since we don't call - // queuefinalizer during marking. - if work.markrootDone { - break - } for fb := allfin; fb != nil; fb = fb.alllink { cnt := uintptr(atomic.Load(&fb.cnt)) - scanblock(uintptr(unsafe.Pointer(&fb.fin[0])), cnt*unsafe.Sizeof(fb.fin[0]), &finptrmask[0], gcw) + scanblock(uintptr(unsafe.Pointer(&fb.fin[0])), cnt*unsafe.Sizeof(fb.fin[0]), &finptrmask[0], gcw, nil) } case i == fixedRootFreeGStacks: - // Only do this once per GC cycle; preferably - // concurrently. - if !work.markrootDone { - // Switch to the system stack so we can call - // stackfree. - systemstack(markrootFreeGStacks) - } + // Switch to the system stack so we can call + // stackfree. + systemstack(markrootFreeGStacks) case baseSpans <= i && i < baseStacks: // mark MSpan.specials @@ -291,7 +248,7 @@ func markrootBlock(b0, n0 uintptr, ptrmask0 *uint8, gcw *gcWork, shard int) { } // Scan this shard. - scanblock(b, n, ptrmask, gcw) + scanblock(b, n, ptrmask, gcw, nil) } // markrootFreeGStacks frees stacks of dead Gs. @@ -342,10 +299,6 @@ func markrootSpans(gcw *gcWork, shard int) { // TODO(austin): There are several ideas for making this more // efficient in issue #11485. - if work.markrootDone { - throw("markrootSpans during second markroot") - } - sg := mheap_.sweepgen spans := mheap_.sweepSpans[mheap_.sweepgen/2%2].block(shard) // Note that work.spans may not include spans that were @@ -358,7 +311,8 @@ func markrootSpans(gcw *gcWork, shard int) { if s.state != mSpanInUse { continue } - if !useCheckmark && s.sweepgen != sg { + // Check that this span was swept (it may be cached or uncached). + if !useCheckmark && !(s.sweepgen == sg || s.sweepgen == sg+3) { // sweepgen was updated (+2) during non-checkmark GC pass print("sweep ", s.sweepgen, " ", sg, "\n") throw("gc: unswept span") @@ -395,7 +349,7 @@ func markrootSpans(gcw *gcWork, shard int) { scanobject(p, gcw) // The special itself is a root. - scanblock(uintptr(unsafe.Pointer(&spf.fn)), sys.PtrSize, &oneptrmask[0], gcw) + scanblock(uintptr(unsafe.Pointer(&spf.fn)), sys.PtrSize, &oneptrmask[0], gcw, nil) } unlock(&s.speciallock) @@ -556,11 +510,6 @@ func gcAssistAlloc1(gp *g, scanWork int64) { // will be more cache friendly. gcw := &getg().m.p.ptr().gcw workDone := gcDrainN(gcw, scanWork) - // If we are near the end of the mark phase - // dispose of the gcw. - if gcBlackenPromptly { - gcw.dispose() - } casgstatus(gp, _Gwaiting, _Grunning) @@ -577,8 +526,7 @@ func gcAssistAlloc1(gp *g, scanWork int64) { incnwait := atomic.Xadd(&work.nwait, +1) if incnwait > work.nproc { println("runtime: work.nwait=", incnwait, - "work.nproc=", work.nproc, - "gcBlackenPromptly=", gcBlackenPromptly) + "work.nproc=", work.nproc) throw("work.nwait > work.nproc") } @@ -737,53 +685,140 @@ func scanstack(gp *g, gcw *gcWork) { if gp == getg() { throw("can't scan our own stack") } - mp := gp.m - if mp != nil && mp.helpgc != 0 { - throw("can't scan gchelper stack") - } - // Shrink the stack if not much of it is being used. During - // concurrent GC, we can do this during concurrent mark. - if !work.markrootDone { - shrinkstack(gp) + // Shrink the stack if not much of it is being used. + shrinkstack(gp) + + var state stackScanState + state.stack = gp.stack + + if stackTraceDebug { + println("stack trace goroutine", gp.goid) } // Scan the saved context register. This is effectively a live // register that gets moved back and forth between the // register and sched.ctxt without a write barrier. if gp.sched.ctxt != nil { - scanblock(uintptr(unsafe.Pointer(&gp.sched.ctxt)), sys.PtrSize, &oneptrmask[0], gcw) + scanblock(uintptr(unsafe.Pointer(&gp.sched.ctxt)), sys.PtrSize, &oneptrmask[0], gcw, &state) } - // Scan the stack. - var cache pcvalueCache + // Scan the stack. Accumulate a list of stack objects. scanframe := func(frame *stkframe, unused unsafe.Pointer) bool { - scanframeworker(frame, &cache, gcw) + scanframeworker(frame, &state, gcw) return true } gentraceback(^uintptr(0), ^uintptr(0), 0, gp, 0, nil, 0x7fffffff, scanframe, nil, 0) tracebackdefers(gp, scanframe, nil) + + // Find and scan all reachable stack objects. + state.buildIndex() + for { + p := state.getPtr() + if p == 0 { + break + } + obj := state.findObject(p) + if obj == nil { + continue + } + t := obj.typ + if t == nil { + // We've already scanned this object. + continue + } + obj.setType(nil) // Don't scan it again. + if stackTraceDebug { + println(" live stkobj at", hex(state.stack.lo+uintptr(obj.off)), "of type", t.string()) + } + gcdata := t.gcdata + var s *mspan + if t.kind&kindGCProg != 0 { + // This path is pretty unlikely, an object large enough + // to have a GC program allocated on the stack. + // We need some space to unpack the program into a straight + // bitmask, which we allocate/free here. + // TODO: it would be nice if there were a way to run a GC + // program without having to store all its bits. We'd have + // to change from a Lempel-Ziv style program to something else. + // Or we can forbid putting objects on stacks if they require + // a gc program (see issue 27447). + s = materializeGCProg(t.ptrdata, gcdata) + gcdata = (*byte)(unsafe.Pointer(s.startAddr)) + } + + scanblock(state.stack.lo+uintptr(obj.off), t.ptrdata, gcdata, gcw, &state) + + if s != nil { + dematerializeGCProg(s) + } + } + + // Deallocate object buffers. + // (Pointer buffers were all deallocated in the loop above.) + for state.head != nil { + x := state.head + state.head = x.next + if stackTraceDebug { + for _, obj := range x.obj[:x.nobj] { + if obj.typ == nil { // reachable + continue + } + println(" dead stkobj at", hex(gp.stack.lo+uintptr(obj.off)), "of type", obj.typ.string()) + // Note: not necessarily really dead - only reachable-from-ptr dead. + } + } + x.nobj = 0 + putempty((*workbuf)(unsafe.Pointer(x))) + } + if state.buf != nil || state.freeBuf != nil { + throw("remaining pointer buffers") + } + gp.gcscanvalid = true } // Scan a stack frame: local variables and function arguments/results. //go:nowritebarrier -func scanframeworker(frame *stkframe, cache *pcvalueCache, gcw *gcWork) { +func scanframeworker(frame *stkframe, state *stackScanState, gcw *gcWork) { if _DebugGC > 1 && frame.continpc != 0 { print("scanframe ", funcname(frame.fn), "\n") } - locals, args := getStackMap(frame, cache, false) + locals, args, objs := getStackMap(frame, &state.cache, false) // Scan local variables if stack frame has been allocated. if locals.n > 0 { size := uintptr(locals.n) * sys.PtrSize - scanblock(frame.varp-size, size, locals.bytedata, gcw) + scanblock(frame.varp-size, size, locals.bytedata, gcw, state) } // Scan arguments. if args.n > 0 { - scanblock(frame.argp, uintptr(args.n)*sys.PtrSize, args.bytedata, gcw) + scanblock(frame.argp, uintptr(args.n)*sys.PtrSize, args.bytedata, gcw, state) + } + + // Add all stack objects to the stack object list. + if frame.varp != 0 { + // varp is 0 for defers, where there are no locals. + // In that case, there can't be a pointer to its args, either. + // (And all args would be scanned above anyway.) + for _, obj := range objs { + off := obj.off + base := frame.varp // locals base pointer + if off >= 0 { + base = frame.argp // arguments and return values base pointer + } + ptr := base + uintptr(off) + if ptr < frame.sp { + // object hasn't been allocated in the frame yet. + continue + } + if stackTraceDebug { + println("stkobj at", hex(ptr), "of type", obj.typ.string()) + } + state.addObject(ptr, obj.typ) + } } } @@ -791,34 +826,26 @@ type gcDrainFlags int const ( gcDrainUntilPreempt gcDrainFlags = 1 << iota - gcDrainNoBlock gcDrainFlushBgCredit gcDrainIdle gcDrainFractional - - // gcDrainBlock means neither gcDrainUntilPreempt or - // gcDrainNoBlock. It is the default, but callers should use - // the constant for documentation purposes. - gcDrainBlock gcDrainFlags = 0 ) // gcDrain scans roots and objects in work buffers, blackening grey -// objects until all roots and work buffers have been drained. +// objects until it is unable to get more work. It may return before +// GC is done; it's the caller's responsibility to balance work from +// other Ps. // // If flags&gcDrainUntilPreempt != 0, gcDrain returns when g.preempt -// is set. This implies gcDrainNoBlock. +// is set. // // If flags&gcDrainIdle != 0, gcDrain returns when there is other work -// to do. This implies gcDrainNoBlock. +// to do. // // If flags&gcDrainFractional != 0, gcDrain self-preempts when // pollFractionalWorkerExit() returns true. This implies // gcDrainNoBlock. // -// If flags&gcDrainNoBlock != 0, gcDrain returns as soon as it is -// unable to get more work. Otherwise, it will block until all -// blocking calls are blocked in gcDrain. -// // If flags&gcDrainFlushBgCredit != 0, gcDrain flushes scan work // credit to gcController.bgScanCredit every gcCreditSlack units of // scan work. @@ -831,7 +858,6 @@ func gcDrain(gcw *gcWork, flags gcDrainFlags) { gp := getg().m.curg preemptible := flags&gcDrainUntilPreempt != 0 - blocking := flags&(gcDrainUntilPreempt|gcDrainIdle|gcDrainFractional|gcDrainNoBlock) == 0 flushBgCredit := flags&gcDrainFlushBgCredit != 0 idle := flags&gcDrainIdle != 0 @@ -875,17 +901,19 @@ func gcDrain(gcw *gcWork, flags gcDrainFlags) { gcw.balance() } - var b uintptr - if blocking { - b = gcw.get() - } else { - b = gcw.tryGetFast() + b := gcw.tryGetFast() + if b == 0 { + b = gcw.tryGet() if b == 0 { + // Flush the write barrier + // buffer; this may create + // more work. + wbBufFlush(nil, 0) b = gcw.tryGet() } } if b == 0 { - // work barrier reached or tryGet failed. + // Unable to get work. break } scanobject(b, gcw) @@ -911,10 +939,6 @@ func gcDrain(gcw *gcWork, flags gcDrainFlags) { } } - // In blocking mode, write barriers are not allowed after this - // point because we must preserve the condition that the work - // buffers are empty. - done: // Flush remaining scan work credit. if gcw.scanWork > 0 { @@ -963,6 +987,12 @@ func gcDrainN(gcw *gcWork, scanWork int64) int64 { b := gcw.tryGetFast() if b == 0 { b = gcw.tryGet() + if b == 0 { + // Flush the write barrier buffer; + // this may create more work. + wbBufFlush(nil, 0) + b = gcw.tryGet() + } } if b == 0 { @@ -1003,8 +1033,9 @@ func gcDrainN(gcw *gcWork, scanWork int64) int64 { // This is used to scan non-heap roots, so it does not update // gcw.bytesMarked or gcw.scanWork. // +// If stk != nil, possible stack pointers are also reported to stk.putPtr. //go:nowritebarrier -func scanblock(b0, n0 uintptr, ptrmask *uint8, gcw *gcWork) { +func scanblock(b0, n0 uintptr, ptrmask *uint8, gcw *gcWork, stk *stackScanState) { // Use local copies of original parameters, so that a stack trace // due to one of the throws below shows the original block // base and extent. @@ -1021,10 +1052,12 @@ func scanblock(b0, n0 uintptr, ptrmask *uint8, gcw *gcWork) { for j := 0; j < 8 && i < n; j++ { if bits&1 != 0 { // Same work as in scanobject; see comments there. - obj := *(*uintptr)(unsafe.Pointer(b + i)) - if obj != 0 { - if obj, span, objIndex := findObject(obj, b, i); obj != 0 { + p := *(*uintptr)(unsafe.Pointer(b + i)) + if p != 0 { + if obj, span, objIndex := findObject(p, b, i); obj != 0 { greyobject(obj, b, i, span, gcw, objIndex) + } else if stk != nil && p >= stk.stack.lo && p < stk.stack.hi { + stk.putPtr(p) } } } @@ -1142,11 +1175,6 @@ func shade(b uintptr) { if obj, span, objIndex := findObject(b, 0, 0); obj != 0 { gcw := &getg().m.p.ptr().gcw greyobject(obj, 0, 0, span, gcw, objIndex) - if gcphase == _GCmarktermination || gcBlackenPromptly { - // Ps aren't allowed to cache work during mark - // termination. - gcw.dispose() - } } } @@ -1239,7 +1267,7 @@ func gcDumpObject(label string, obj, off uintptr) { skipped := false size := s.elemsize - if s.state == _MSpanManual && size == 0 { + if s.state == mSpanManual && size == 0 { // We're printing something from a stack frame. We // don't know how big it is, so just show up to an // including off. @@ -1276,18 +1304,13 @@ func gcDumpObject(label string, obj, off uintptr) { //go:nowritebarrier //go:nosplit func gcmarknewobject(obj, size, scanSize uintptr) { - if useCheckmark && !gcBlackenPromptly { // The world should be stopped so this should not happen. + if useCheckmark { // The world should be stopped so this should not happen. throw("gcmarknewobject called while doing checkmark") } markBitsForAddr(obj).setMarked() gcw := &getg().m.p.ptr().gcw gcw.bytesMarked += uint64(size) gcw.scanWork += int64(scanSize) - if gcBlackenPromptly { - // There shouldn't be anything in the work queue, but - // we still need to flush stats. - gcw.dispose() - } } // gcMarkTinyAllocs greys all active tiny alloc blocks. @@ -1302,9 +1325,6 @@ func gcMarkTinyAllocs() { _, span, objIndex := findObject(c.tiny, 0, 0) gcw := &p.gcw greyobject(c.tiny, 0, 0, span, gcw, objIndex) - if gcBlackenPromptly { - gcw.dispose() - } } } @@ -1335,7 +1355,7 @@ var useCheckmark = false func initCheckmarks() { useCheckmark = true for _, s := range mheap_.allspans { - if s.state == _MSpanInUse { + if s.state == mSpanInUse { heapBitsForAddr(s.base()).initCheckmarkSpan(s.layout()) } } @@ -1344,7 +1364,7 @@ func initCheckmarks() { func clearCheckmarks() { useCheckmark = false for _, s := range mheap_.allspans { - if s.state == _MSpanInUse { + if s.state == mSpanInUse { heapBitsForAddr(s.base()).clearCheckmarkSpan(s.layout()) } } diff --git a/src/runtime/mgcstack.go b/src/runtime/mgcstack.go new file mode 100644 index 0000000000..86e60d4381 --- /dev/null +++ b/src/runtime/mgcstack.go @@ -0,0 +1,330 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Garbage collector: stack objects and stack tracing +// See the design doc at https://docs.google.com/document/d/1un-Jn47yByHL7I0aVIP_uVCMxjdM5mpelJhiKlIqxkE/edit?usp=sharing +// Also see issue 22350. + +// Stack tracing solves the problem of determining which parts of the +// stack are live and should be scanned. It runs as part of scanning +// a single goroutine stack. +// +// Normally determining which parts of the stack are live is easy to +// do statically, as user code has explicit references (reads and +// writes) to stack variables. The compiler can do a simple dataflow +// analysis to determine liveness of stack variables at every point in +// the code. See cmd/compile/internal/gc/plive.go for that analysis. +// +// However, when we take the address of a stack variable, determining +// whether that variable is still live is less clear. We can still +// look for static accesses, but accesses through a pointer to the +// variable are difficult in general to track statically. That pointer +// can be passed among functions on the stack, conditionally retained, +// etc. +// +// Instead, we will track pointers to stack variables dynamically. +// All pointers to stack-allocated variables will themselves be on the +// stack somewhere (or in associated locations, like defer records), so +// we can find them all efficiently. +// +// Stack tracing is organized as a mini garbage collection tracing +// pass. The objects in this garbage collection are all the variables +// on the stack whose address is taken, and which themselves contain a +// pointer. We call these variables "stack objects". +// +// We begin by determining all the stack objects on the stack and all +// the statically live pointers that may point into the stack. We then +// process each pointer to see if it points to a stack object. If it +// does, we scan that stack object. It may contain pointers into the +// heap, in which case those pointers are passed to the main garbage +// collection. It may also contain pointers into the stack, in which +// case we add them to our set of stack pointers. +// +// Once we're done processing all the pointers (including the ones we +// added during processing), we've found all the stack objects that +// are live. Any dead stack objects are not scanned and their contents +// will not keep heap objects live. Unlike the main garbage +// collection, we can't sweep the dead stack objects; they live on in +// a moribund state until the stack frame that contains them is +// popped. +// +// A stack can look like this: +// +// +----------+ +// | foo() | +// | +------+ | +// | | A | | <---\ +// | +------+ | | +// | | | +// | +------+ | | +// | | B | | | +// | +------+ | | +// | | | +// +----------+ | +// | bar() | | +// | +------+ | | +// | | C | | <-\ | +// | +----|-+ | | | +// | | | | | +// | +----v-+ | | | +// | | D ---------/ +// | +------+ | | +// | | | +// +----------+ | +// | baz() | | +// | +------+ | | +// | | E -------/ +// | +------+ | +// | ^ | +// | F: --/ | +// | | +// +----------+ +// +// foo() calls bar() calls baz(). Each has a frame on the stack. +// foo() has stack objects A and B. +// bar() has stack objects C and D, with C pointing to D and D pointing to A. +// baz() has a stack object E pointing to C, and a local variable F pointing to E. +// +// Starting from the pointer in local variable F, we will eventually +// scan all of E, C, D, and A (in that order). B is never scanned +// because there is no live pointer to it. If B is also statically +// dead (meaning that foo() never accesses B again after it calls +// bar()), then B's pointers into the heap are not considered live. + +package runtime + +import ( + "runtime/internal/sys" + "unsafe" +) + +const stackTraceDebug = false + +// Buffer for pointers found during stack tracing. +// Must be smaller than or equal to workbuf. +// +//go:notinheap +type stackWorkBuf struct { + stackWorkBufHdr + obj [(_WorkbufSize - unsafe.Sizeof(stackWorkBufHdr{})) / sys.PtrSize]uintptr +} + +// Header declaration must come after the buf declaration above, because of issue #14620. +// +//go:notinheap +type stackWorkBufHdr struct { + workbufhdr + next *stackWorkBuf // linked list of workbufs + // Note: we could theoretically repurpose lfnode.next as this next pointer. + // It would save 1 word, but that probably isn't worth busting open + // the lfnode API. +} + +// Buffer for stack objects found on a goroutine stack. +// Must be smaller than or equal to workbuf. +// +//go:notinheap +type stackObjectBuf struct { + stackObjectBufHdr + obj [(_WorkbufSize - unsafe.Sizeof(stackObjectBufHdr{})) / unsafe.Sizeof(stackObject{})]stackObject +} + +//go:notinheap +type stackObjectBufHdr struct { + workbufhdr + next *stackObjectBuf +} + +func init() { + if unsafe.Sizeof(stackWorkBuf{}) > unsafe.Sizeof(workbuf{}) { + panic("stackWorkBuf too big") + } + if unsafe.Sizeof(stackObjectBuf{}) > unsafe.Sizeof(workbuf{}) { + panic("stackObjectBuf too big") + } +} + +// A stackObject represents a variable on the stack that has had +// its address taken. +// +//go:notinheap +type stackObject struct { + off uint32 // offset above stack.lo + size uint32 // size of object + typ *_type // type info (for ptr/nonptr bits). nil if object has been scanned. + left *stackObject // objects with lower addresses + right *stackObject // objects with higher addresses +} + +// obj.typ = typ, but with no write barrier. +//go:nowritebarrier +func (obj *stackObject) setType(typ *_type) { + // Types of stack objects are always in read-only memory, not the heap. + // So not using a write barrier is ok. + *(*uintptr)(unsafe.Pointer(&obj.typ)) = uintptr(unsafe.Pointer(typ)) +} + +// A stackScanState keeps track of the state used during the GC walk +// of a goroutine. +// +//go:notinheap +type stackScanState struct { + cache pcvalueCache + + // stack limits + stack stack + + // buf contains the set of possible pointers to stack objects. + // Organized as a LIFO linked list of buffers. + // All buffers except possibly the head buffer are full. + buf *stackWorkBuf + freeBuf *stackWorkBuf // keep around one free buffer for allocation hysteresis + + // list of stack objects + // Objects are in increasing address order. + head *stackObjectBuf + tail *stackObjectBuf + nobjs int + + // root of binary tree for fast object lookup by address + // Initialized by buildIndex. + root *stackObject +} + +// Add p as a potential pointer to a stack object. +// p must be a stack address. +func (s *stackScanState) putPtr(p uintptr) { + if p < s.stack.lo || p >= s.stack.hi { + throw("address not a stack address") + } + buf := s.buf + if buf == nil { + // Initial setup. + buf = (*stackWorkBuf)(unsafe.Pointer(getempty())) + buf.nobj = 0 + buf.next = nil + s.buf = buf + } else if buf.nobj == len(buf.obj) { + if s.freeBuf != nil { + buf = s.freeBuf + s.freeBuf = nil + } else { + buf = (*stackWorkBuf)(unsafe.Pointer(getempty())) + } + buf.nobj = 0 + buf.next = s.buf + s.buf = buf + } + buf.obj[buf.nobj] = p + buf.nobj++ +} + +// Remove and return a potential pointer to a stack object. +// Returns 0 if there are no more pointers available. +func (s *stackScanState) getPtr() uintptr { + buf := s.buf + if buf == nil { + // Never had any data. + return 0 + } + if buf.nobj == 0 { + if s.freeBuf != nil { + // Free old freeBuf. + putempty((*workbuf)(unsafe.Pointer(s.freeBuf))) + } + // Move buf to the freeBuf. + s.freeBuf = buf + buf = buf.next + s.buf = buf + if buf == nil { + // No more data. + putempty((*workbuf)(unsafe.Pointer(s.freeBuf))) + s.freeBuf = nil + return 0 + } + } + buf.nobj-- + return buf.obj[buf.nobj] +} + +// addObject adds a stack object at addr of type typ to the set of stack objects. +func (s *stackScanState) addObject(addr uintptr, typ *_type) { + x := s.tail + if x == nil { + // initial setup + x = (*stackObjectBuf)(unsafe.Pointer(getempty())) + x.next = nil + s.head = x + s.tail = x + } + if x.nobj > 0 && uint32(addr-s.stack.lo) < x.obj[x.nobj-1].off+x.obj[x.nobj-1].size { + throw("objects added out of order or overlapping") + } + if x.nobj == len(x.obj) { + // full buffer - allocate a new buffer, add to end of linked list + y := (*stackObjectBuf)(unsafe.Pointer(getempty())) + y.next = nil + x.next = y + s.tail = y + x = y + } + obj := &x.obj[x.nobj] + x.nobj++ + obj.off = uint32(addr - s.stack.lo) + obj.size = uint32(typ.size) + obj.setType(typ) + // obj.left and obj.right will be initalized by buildIndex before use. + s.nobjs++ +} + +// buildIndex initializes s.root to a binary search tree. +// It should be called after all addObject calls but before +// any call of findObject. +func (s *stackScanState) buildIndex() { + s.root, _, _ = binarySearchTree(s.head, 0, s.nobjs) +} + +// Build a binary search tree with the n objects in the list +// x.obj[idx], x.obj[idx+1], ..., x.next.obj[0], ... +// Returns the root of that tree, and the buf+idx of the nth object after x.obj[idx]. +// (The first object that was not included in the binary search tree.) +// If n == 0, returns nil, x. +func binarySearchTree(x *stackObjectBuf, idx int, n int) (root *stackObject, restBuf *stackObjectBuf, restIdx int) { + if n == 0 { + return nil, x, idx + } + var left, right *stackObject + left, x, idx = binarySearchTree(x, idx, n/2) + root = &x.obj[idx] + idx++ + if idx == len(x.obj) { + x = x.next + idx = 0 + } + right, x, idx = binarySearchTree(x, idx, n-n/2-1) + root.left = left + root.right = right + return root, x, idx +} + +// findObject returns the stack object containing address a, if any. +// Must have called buildIndex previously. +func (s *stackScanState) findObject(a uintptr) *stackObject { + off := uint32(a - s.stack.lo) + obj := s.root + for { + if obj == nil { + return nil + } + if off < obj.off { + obj = obj.left + continue + } + if off >= obj.off+obj.size { + obj = obj.right + continue + } + return obj + } +} diff --git a/src/runtime/mgcsweep.go b/src/runtime/mgcsweep.go index c7baa455fe..00950aede2 100644 --- a/src/runtime/mgcsweep.go +++ b/src/runtime/mgcsweep.go @@ -88,10 +88,11 @@ func sweepone() uintptr { } atomic.Xadd(&mheap_.sweepers, +1) - npages := ^uintptr(0) + // Find a span to sweep. + var s *mspan sg := mheap_.sweepgen for { - s := mheap_.sweepSpans[1-sg/2%2].pop() + s = mheap_.sweepSpans[1-sg/2%2].pop() if s == nil { atomic.Store(&mheap_.sweepdone, 1) break @@ -106,9 +107,14 @@ func sweepone() uintptr { } continue } - if s.sweepgen != sg-2 || !atomic.Cas(&s.sweepgen, sg-2, sg-1) { - continue + if s.sweepgen == sg-2 && atomic.Cas(&s.sweepgen, sg-2, sg-1) { + break } + } + + // Sweep the span we found. + npages := ^uintptr(0) + if s != nil { npages = s.npages if !s.sweep(false) { // Span is still in-use, so this returned no @@ -116,7 +122,6 @@ func sweepone() uintptr { // move to the swept in-use list. npages = 0 } - break } // Decrement the number of active sweepers and if this is the @@ -156,16 +161,21 @@ func (s *mspan) ensureSwept() { } sg := mheap_.sweepgen - if atomic.Load(&s.sweepgen) == sg { + spangen := atomic.Load(&s.sweepgen) + if spangen == sg || spangen == sg+3 { return } - // The caller must be sure that the span is a MSpanInUse span. + // The caller must be sure that the span is a mSpanInUse span. if atomic.Cas(&s.sweepgen, sg-2, sg-1) { s.sweep(false) return } // unfortunate condition, and we don't have efficient means to wait - for atomic.Load(&s.sweepgen) != sg { + for { + spangen := atomic.Load(&s.sweepgen) + if spangen == sg || spangen == sg+3 { + break + } osyield() } } @@ -339,18 +349,18 @@ func (s *mspan) sweep(preserve bool) bool { // Free large span to heap // NOTE(rsc,dvyukov): The original implementation of efence - // in CL 22060046 used SysFree instead of SysFault, so that + // in CL 22060046 used sysFree instead of sysFault, so that // the operating system would eventually give the memory // back to us again, so that an efence program could run // longer without running out of memory. Unfortunately, - // calling SysFree here without any kind of adjustment of the + // calling sysFree here without any kind of adjustment of the // heap data structures means that when the memory does // come back to us, we have the wrong metadata for it, either in // the MSpan structures or in the garbage collection bitmap. - // Using SysFault here means that the program will run out of + // Using sysFault here means that the program will run out of // memory fairly quickly in efence mode, but at least it won't // have mysterious crashes due to confused memory reuse. - // It should be possible to switch back to SysFree if we also + // It should be possible to switch back to sysFree if we also // implement and then call some kind of MHeap_DeleteSpan. if debug.efence > 0 { s.limit = 0 // prevent mlookup from finding this span diff --git a/src/runtime/mgcwork.go b/src/runtime/mgcwork.go index 99771e2e57..c32c5eddd7 100644 --- a/src/runtime/mgcwork.go +++ b/src/runtime/mgcwork.go @@ -46,10 +46,7 @@ func init() { // // (preemption must be disabled) // gcw := &getg().m.p.ptr().gcw -// .. call gcw.put() to produce and gcw.get() to consume .. -// if gcBlackenPromptly { -// gcw.dispose() -// } +// .. call gcw.put() to produce and gcw.tryGet() to consume .. // // It's important that any use of gcWork during the mark phase prevent // the garbage collector from transitioning to mark termination since @@ -83,6 +80,12 @@ type gcWork struct { // Scan work performed on this gcWork. This is aggregated into // gcController by dispose and may also be flushed by callers. scanWork int64 + + // flushedWork indicates that a non-empty work buffer was + // flushed to the global work list since the last gcMarkDone + // termination check. Specifically, this indicates that this + // gcWork may have communicated work to another gcWork. + flushedWork bool } // Most of the methods of gcWork are go:nowritebarrierrec because the @@ -116,6 +119,7 @@ func (w *gcWork) put(obj uintptr) { wbuf = w.wbuf1 if wbuf.nobj == len(wbuf.obj) { putfull(wbuf) + w.flushedWork = true wbuf = getempty() w.wbuf1 = wbuf flushed = true @@ -169,6 +173,7 @@ func (w *gcWork) putBatch(obj []uintptr) { for len(obj) > 0 { for wbuf.nobj == len(wbuf.obj) { putfull(wbuf) + w.flushedWork = true w.wbuf1, w.wbuf2 = w.wbuf2, getempty() wbuf = w.wbuf1 flushed = true @@ -231,37 +236,6 @@ func (w *gcWork) tryGetFast() uintptr { return wbuf.obj[wbuf.nobj] } -// get dequeues a pointer for the garbage collector to trace, blocking -// if necessary to ensure all pointers from all queues and caches have -// been retrieved. get returns 0 if there are no pointers remaining. -//go:nowritebarrierrec -func (w *gcWork) get() uintptr { - wbuf := w.wbuf1 - if wbuf == nil { - w.init() - wbuf = w.wbuf1 - // wbuf is empty at this point. - } - if wbuf.nobj == 0 { - w.wbuf1, w.wbuf2 = w.wbuf2, w.wbuf1 - wbuf = w.wbuf1 - if wbuf.nobj == 0 { - owbuf := wbuf - wbuf = getfull() - if wbuf == nil { - return 0 - } - putempty(owbuf) - w.wbuf1 = wbuf - } - } - - // TODO: This might be a good place to add prefetch code - - wbuf.nobj-- - return wbuf.obj[wbuf.nobj] -} - // dispose returns any cached pointers to the global queue. // The buffers are being put on the full queue so that the // write barriers will not simply reacquire them before the @@ -275,6 +249,7 @@ func (w *gcWork) dispose() { putempty(wbuf) } else { putfull(wbuf) + w.flushedWork = true } w.wbuf1 = nil @@ -283,6 +258,7 @@ func (w *gcWork) dispose() { putempty(wbuf) } else { putfull(wbuf) + w.flushedWork = true } w.wbuf2 = nil } @@ -309,9 +285,11 @@ func (w *gcWork) balance() { } if wbuf := w.wbuf2; wbuf.nobj != 0 { putfull(wbuf) + w.flushedWork = true w.wbuf2 = getempty() } else if wbuf := w.wbuf1; wbuf.nobj > 4 { w.wbuf1 = handoff(wbuf) + w.flushedWork = true // handoff did putfull } else { return } @@ -440,61 +418,6 @@ func trygetfull() *workbuf { return b } -// Get a full work buffer off the work.full list. -// If nothing is available wait until all the other gc helpers have -// finished and then return nil. -// getfull acts as a barrier for work.nproc helpers. As long as one -// gchelper is actively marking objects it -// may create a workbuffer that the other helpers can work on. -// The for loop either exits when a work buffer is found -// or when _all_ of the work.nproc GC helpers are in the loop -// looking for work and thus not capable of creating new work. -// This is in fact the termination condition for the STW mark -// phase. -//go:nowritebarrier -func getfull() *workbuf { - b := (*workbuf)(work.full.pop()) - if b != nil { - b.checknonempty() - return b - } - - incnwait := atomic.Xadd(&work.nwait, +1) - if incnwait > work.nproc { - println("runtime: work.nwait=", incnwait, "work.nproc=", work.nproc) - throw("work.nwait > work.nproc") - } - for i := 0; ; i++ { - if work.full != 0 { - decnwait := atomic.Xadd(&work.nwait, -1) - if decnwait == work.nproc { - println("runtime: work.nwait=", decnwait, "work.nproc=", work.nproc) - throw("work.nwait > work.nproc") - } - b = (*workbuf)(work.full.pop()) - if b != nil { - b.checknonempty() - return b - } - incnwait := atomic.Xadd(&work.nwait, +1) - if incnwait > work.nproc { - println("runtime: work.nwait=", incnwait, "work.nproc=", work.nproc) - throw("work.nwait > work.nproc") - } - } - if work.nwait == work.nproc && work.markrootNext >= work.markrootJobs { - return nil - } - if i < 10 { - procyield(20) - } else if i < 20 { - osyield() - } else { - usleep(100) - } - } -} - //go:nowritebarrier func handoff(b *workbuf) *workbuf { // Make new buffer with half of b's pointers. diff --git a/src/runtime/mheap.go b/src/runtime/mheap.go index 00ecfa2d66..7a11bdc058 100644 --- a/src/runtime/mheap.go +++ b/src/runtime/mheap.go @@ -82,7 +82,7 @@ type mheap struct { // accounting for current progress. If we could only adjust // the slope, it would create a discontinuity in debt if any // progress has already been made. - pagesInUse uint64 // pages of spans in stats _MSpanInUse; R/W with mheap.lock + pagesInUse uint64 // pages of spans in stats mSpanInUse; R/W with mheap.lock pagesSwept uint64 // pages swept this cycle; updated atomically pagesSweptBasis uint64 // pagesSwept to use as the origin of the sweep ratio; updated atomically sweepHeapLiveBasis uint64 // value of heap_live to use as the origin of sweep ratio; written with lock, read without @@ -199,18 +199,18 @@ type arenaHint struct { // An MSpan is a run of pages. // -// When a MSpan is in the heap free list, state == MSpanFree +// When a MSpan is in the heap free list, state == mSpanFree // and heapmap(s->start) == span, heapmap(s->start+s->npages-1) == span. // -// When a MSpan is allocated, state == MSpanInUse or MSpanManual +// When a MSpan is allocated, state == mSpanInUse or mSpanManual // and heapmap(i) == span for all s->start <= i < s->start+s->npages. // Every MSpan is in one doubly-linked list, // either one of the MHeap's free lists or one of the // MCentral's span lists. -// An MSpan representing actual memory has state _MSpanInUse, -// _MSpanManual, or _MSpanFree. Transitions between these states are +// An MSpan representing actual memory has state mSpanInUse, +// mSpanManual, or mSpanFree. Transitions between these states are // constrained as follows: // // * A span may transition from free to in-use or manual during any GC @@ -226,19 +226,19 @@ type arenaHint struct { type mSpanState uint8 const ( - _MSpanDead mSpanState = iota - _MSpanInUse // allocated for garbage collected heap - _MSpanManual // allocated for manual management (e.g., stack allocator) - _MSpanFree + mSpanDead mSpanState = iota + mSpanInUse // allocated for garbage collected heap + mSpanManual // allocated for manual management (e.g., stack allocator) + mSpanFree ) // mSpanStateNames are the names of the span states, indexed by // mSpanState. var mSpanStateNames = []string{ - "_MSpanDead", - "_MSpanInUse", - "_MSpanManual", - "_MSpanFree", + "mSpanDead", + "mSpanInUse", + "mSpanManual", + "mSpanFree", } // mSpanList heads a linked list of spans. @@ -258,7 +258,7 @@ type mspan struct { startAddr uintptr // address of first byte of span aka s.base() npages uintptr // number of pages in span - manualFreeList gclinkptr // list of free objects in _MSpanManual spans + manualFreeList gclinkptr // list of free objects in mSpanManual spans // freeindex is the slot index between 0 and nelems at which to begin scanning // for the next free object in this span. @@ -317,6 +317,8 @@ type mspan struct { // if sweepgen == h->sweepgen - 2, the span needs sweeping // if sweepgen == h->sweepgen - 1, the span is currently being swept // if sweepgen == h->sweepgen, the span is swept and ready to use + // if sweepgen == h->sweepgen + 1, the span was cached before sweep began and is still cached, and needs sweeping + // if sweepgen == h->sweepgen + 3, the span was swept and then cached and is still cached // h->sweepgen is incremented by 2 after every GC sweepgen uint32 @@ -324,7 +326,6 @@ type mspan struct { baseMask uint16 // if non-0, elemsize is a power of 2, & this will get object allocation base allocCount uint16 // number of allocated objects spanclass spanClass // size class and noscan (uint8) - incache bool // being used by an mcache state mSpanState // mspaninuse etc needzero uint8 // needs to be zeroed before allocation divShift uint8 // for divide by elemsize - divMagic.shift @@ -458,7 +459,7 @@ func (i arenaIdx) l2() uint { } // inheap reports whether b is a pointer into a (potentially dead) heap object. -// It returns false for pointers into _MSpanManual spans. +// It returns false for pointers into mSpanManual spans. // Non-preemptible because it is used by write barriers. //go:nowritebarrier //go:nosplit @@ -477,7 +478,7 @@ func inHeapOrStack(b uintptr) bool { return false } switch s.state { - case mSpanInUse, _MSpanManual: + case mSpanInUse, mSpanManual: return b < s.limit default: return false @@ -696,7 +697,7 @@ func (h *mheap) alloc_m(npage uintptr, spanclass spanClass, large bool) *mspan { // able to map interior pointer to containing span. atomic.Store(&s.sweepgen, h.sweepgen) h.sweepSpans[h.sweepgen/2%2].push(s) // Add to swept in-use list. - s.state = _MSpanInUse + s.state = mSpanInUse s.allocCount = 0 s.spanclass = spanclass if sizeclass := spanclass.sizeclass(); sizeclass == 0 { @@ -788,7 +789,7 @@ func (h *mheap) allocManual(npage uintptr, stat *uint64) *mspan { lock(&h.lock) s := h.allocSpanLocked(npage, stat) if s != nil { - s.state = _MSpanManual + s.state = mSpanManual s.manualFreeList = 0 s.allocCount = 0 s.spanclass = 0 @@ -829,7 +830,7 @@ func (h *mheap) setSpans(base, npage uintptr, s *mspan) { // Allocates a span of the given size. h must be locked. // The returned span has been removed from the -// free list, but its state is still MSpanFree. +// free list, but its state is still mSpanFree. func (h *mheap) allocSpanLocked(npage uintptr, stat *uint64) *mspan { var list *mSpanList var s *mspan @@ -857,7 +858,7 @@ func (h *mheap) allocSpanLocked(npage uintptr, stat *uint64) *mspan { HaveSpan: // Mark span in use. - if s.state != _MSpanFree { + if s.state != mSpanFree { throw("MHeap_AllocLocked - MSpan not free") } if s.npages < npage { @@ -878,10 +879,10 @@ HaveSpan: h.setSpan(t.base(), t) h.setSpan(t.base()+t.npages*pageSize-1, t) t.needzero = s.needzero - s.state = _MSpanManual // prevent coalescing with s - t.state = _MSpanManual + s.state = mSpanManual // prevent coalescing with s + t.state = mSpanManual h.freeSpanLocked(t, false, false, s.unusedsince) - s.state = _MSpanFree + s.state = mSpanFree } s.unusedsince = 0 @@ -930,7 +931,7 @@ func (h *mheap) grow(npage uintptr) bool { s.init(uintptr(v), size/pageSize) h.setSpans(s.base(), s.npages, s) atomic.Store(&s.sweepgen, h.sweepgen) - s.state = _MSpanInUse + s.state = mSpanInUse h.pagesInUse += uint64(s.npages) h.freeSpanLocked(s, false, true, 0) return true @@ -986,11 +987,11 @@ func (h *mheap) freeManual(s *mspan, stat *uint64) { // s must be on a busy list (h.busy or h.busylarge) or unlinked. func (h *mheap) freeSpanLocked(s *mspan, acctinuse, acctidle bool, unusedsince int64) { switch s.state { - case _MSpanManual: + case mSpanManual: if s.allocCount != 0 { throw("MHeap_FreeSpanLocked - invalid stack free") } - case _MSpanInUse: + case mSpanInUse: if s.allocCount != 0 || s.sweepgen != h.sweepgen { print("MHeap_FreeSpanLocked - span ", s, " ptr ", hex(s.base()), " allocCount ", s.allocCount, " sweepgen ", s.sweepgen, "/", h.sweepgen, "\n") throw("MHeap_FreeSpanLocked - invalid free") @@ -1006,7 +1007,7 @@ func (h *mheap) freeSpanLocked(s *mspan, acctinuse, acctidle bool, unusedsince i if acctidle { memstats.heap_idle += uint64(s.npages << _PageShift) } - s.state = _MSpanFree + s.state = mSpanFree if s.inList() { h.busyList(s.npages).remove(s) } @@ -1020,7 +1021,7 @@ func (h *mheap) freeSpanLocked(s *mspan, acctinuse, acctidle bool, unusedsince i s.npreleased = 0 // Coalesce with earlier, later spans. - if before := spanOf(s.base() - 1); before != nil && before.state == _MSpanFree { + if before := spanOf(s.base() - 1); before != nil && before.state == mSpanFree { // Now adjust s. s.startAddr = before.startAddr s.npages += before.npages @@ -1035,12 +1036,12 @@ func (h *mheap) freeSpanLocked(s *mspan, acctinuse, acctidle bool, unusedsince i } else { h.freeList(before.npages).remove(before) } - before.state = _MSpanDead + before.state = mSpanDead h.spanalloc.free(unsafe.Pointer(before)) } // Now check to see if next (greater addresses) span is free and can be coalesced. - if after := spanOf(s.base() + s.npages*pageSize); after != nil && after.state == _MSpanFree { + if after := spanOf(s.base() + s.npages*pageSize); after != nil && after.state == mSpanFree { s.npages += after.npages s.npreleased += after.npreleased s.needzero |= after.needzero @@ -1050,7 +1051,7 @@ func (h *mheap) freeSpanLocked(s *mspan, acctinuse, acctidle bool, unusedsince i } else { h.freeList(after.npages).remove(after) } - after.state = _MSpanDead + after.state = mSpanDead h.spanalloc.free(unsafe.Pointer(after)) } @@ -1185,9 +1186,8 @@ func (span *mspan) init(base uintptr, npages uintptr) { span.npages = npages span.allocCount = 0 span.spanclass = 0 - span.incache = false span.elemsize = 0 - span.state = _MSpanDead + span.state = mSpanDead span.unusedsince = 0 span.npreleased = 0 span.speciallock.key = 0 @@ -1437,10 +1437,7 @@ func addfinalizer(p unsafe.Pointer, f *funcval, nret uintptr, fint *_type, ot *p scanobject(base, gcw) // Mark the finalizer itself, since the // special isn't part of the GC'd heap. - scanblock(uintptr(unsafe.Pointer(&s.fn)), sys.PtrSize, &oneptrmask[0], gcw) - if gcBlackenPromptly { - gcw.dispose() - } + scanblock(uintptr(unsafe.Pointer(&s.fn)), sys.PtrSize, &oneptrmask[0], gcw, nil) releasem(mp) } return true diff --git a/src/runtime/mmap.go b/src/runtime/mmap.go index fe09e7029e..2868f3fd4e 100644 --- a/src/runtime/mmap.go +++ b/src/runtime/mmap.go @@ -10,6 +10,7 @@ // +build !linux !arm64 // +build !js // +build !darwin +// +build !aix package runtime diff --git a/src/runtime/mprof.go b/src/runtime/mprof.go index 43e4810d97..2bd41b650f 100644 --- a/src/runtime/mprof.go +++ b/src/runtime/mprof.go @@ -723,7 +723,7 @@ func GoroutineProfile(p []StackRecord) (n int, ok bool) { isOK := func(gp1 *g) bool { // Checking isSystemGoroutine here makes GoroutineProfile // consistent with both NumGoroutine and Stack. - return gp1 != gp && readgstatus(gp1) != _Gdead && !isSystemGoroutine(gp1) + return gp1 != gp && readgstatus(gp1) != _Gdead && !isSystemGoroutine(gp1, false) } stopTheWorld("profile") diff --git a/src/runtime/mstats.go b/src/runtime/mstats.go index f67d05414d..1bd6566052 100644 --- a/src/runtime/mstats.go +++ b/src/runtime/mstats.go @@ -38,7 +38,7 @@ type mstats struct { heap_alloc uint64 // bytes allocated and not yet freed (same as alloc above) heap_sys uint64 // virtual address space obtained from system for GC'd heap heap_idle uint64 // bytes in idle spans - heap_inuse uint64 // bytes in _MSpanInUse spans + heap_inuse uint64 // bytes in mSpanInUse spans heap_released uint64 // bytes released to the os heap_objects uint64 // total number of allocated objects diff --git a/src/runtime/mwbbuf.go b/src/runtime/mwbbuf.go index 4df16d55b8..f35f7286ac 100644 --- a/src/runtime/mwbbuf.go +++ b/src/runtime/mwbbuf.go @@ -79,7 +79,7 @@ const ( func (b *wbBuf) reset() { start := uintptr(unsafe.Pointer(&b.buf[0])) b.next = start - if gcBlackenPromptly || writeBarrier.cgo { + if writeBarrier.cgo { // Effectively disable the buffer by forcing a flush // on every barrier. b.end = uintptr(unsafe.Pointer(&b.buf[wbBufEntryPointers])) @@ -107,6 +107,11 @@ func (b *wbBuf) discard() { b.next = uintptr(unsafe.Pointer(&b.buf[0])) } +// empty returns true if b contains no pointers. +func (b *wbBuf) empty() bool { + return b.next == uintptr(unsafe.Pointer(&b.buf[0])) +} + // putFast adds old and new to the write barrier buffer and returns // false if a flush is necessary. Callers should use this as: // @@ -270,9 +275,4 @@ func wbBufFlush1(_p_ *p) { // Enqueue the greyed objects. gcw.putBatch(ptrs[:pos]) - if gcphase == _GCmarktermination || gcBlackenPromptly { - // Ps aren't allowed to cache work during mark - // termination. - gcw.dispose() - } } diff --git a/src/runtime/netpoll.go b/src/runtime/netpoll.go index f9c422650a..da822a7308 100644 --- a/src/runtime/netpoll.go +++ b/src/runtime/netpoll.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris windows +// +build aix darwin dragonfly freebsd js,wasm linux nacl netbsd openbsd solaris windows package runtime @@ -166,8 +166,8 @@ func poll_runtime_pollWait(pd *pollDesc, mode int) int { if err != 0 { return err } - // As for now only Solaris uses level-triggered IO. - if GOOS == "solaris" { + // As for now only Solaris and AIX use level-triggered IO. + if GOOS == "solaris" || GOOS == "aix" { netpollarm(pd, mode) } for !netpollblock(pd, int32(mode), false) { diff --git a/src/runtime/netpoll_aix.go b/src/runtime/netpoll_aix.go new file mode 100644 index 0000000000..1e886dae94 --- /dev/null +++ b/src/runtime/netpoll_aix.go @@ -0,0 +1,247 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package runtime + +import "unsafe" + +// This is based on the former libgo/runtime/netpoll_select.c implementation +// except that it uses poll instead of select and is written in Go. +// It's also based on Solaris implementation for the arming mechanisms + +//go:cgo_import_dynamic libc_poll poll "libc.a/shr_64.o" +//go:linkname libc_poll libc_poll + +var libc_poll libFunc + +//go:nosplit +func poll(pfds *pollfd, npfds uintptr, timeout uintptr) (int32, int32) { + r, err := syscall3(&libc_poll, uintptr(unsafe.Pointer(pfds)), npfds, timeout) + return int32(r), int32(err) +} + +//go:nosplit +func fcntl(fd, cmd int32, arg uintptr) int32 { + r, _ := syscall3(&libc_fcntl, uintptr(fd), uintptr(cmd), arg) + return int32(r) +} + +// pollfd represents the poll structure for AIX operating system. +type pollfd struct { + fd int32 + events int16 + revents int16 +} + +const _POLLIN = 0x0001 +const _POLLOUT = 0x0002 +const _POLLHUP = 0x2000 +const _POLLERR = 0x4000 +const _O_NONBLOCK = 0x4 + +var ( + pfds []pollfd + pds []*pollDesc + mtxpoll mutex + mtxset mutex + rdwake int32 + wrwake int32 + pendingUpdates int32 +) + +const pollVerbose = false + +func netpollinit() { + var p [2]int32 + + // Create the pipe we use to wakeup poll. + if err := pipe(&p[0]); err < 0 { + throw("netpollinit: failed to create pipe") + } + rdwake = p[0] + wrwake = p[1] + + fl := uintptr(fcntl(rdwake, _F_GETFL, 0)) + fcntl(rdwake, _F_SETFL, fl|_O_NONBLOCK) + fcntl(rdwake, _F_SETFD, _FD_CLOEXEC) + + fl = uintptr(fcntl(wrwake, _F_GETFL, 0)) + fcntl(wrwake, _F_SETFL, fl|_O_NONBLOCK) + fcntl(wrwake, _F_SETFD, _FD_CLOEXEC) + + // Pre-allocate array of pollfd structures for poll. + if pollVerbose { + println("*** allocating") + } + pfds = make([]pollfd, 1, 128) + if pollVerbose { + println("*** allocating done", &pfds[0]) + } + + // Poll the read side of the pipe. + pfds[0].fd = rdwake + pfds[0].events = _POLLIN + + pds = make([]*pollDesc, 1, 128) + pds[0] = nil +} + +func netpolldescriptor() uintptr { + // Both fd must be returned + if rdwake > 0xFFFF || wrwake > 0xFFFF { + throw("netpolldescriptor: invalid fd number") + } + return uintptr(rdwake<<16 | wrwake) +} + +// netpollwakeup writes on wrwake to wakeup poll before any changes. +func netpollwakeup() { + if pendingUpdates == 0 { + pendingUpdates = 1 + if pollVerbose { + println("*** writing 1 byte") + } + b := [1]byte{0} + write(uintptr(wrwake), unsafe.Pointer(&b[0]), 1) + } +} + +func netpollopen(fd uintptr, pd *pollDesc) int32 { + if pollVerbose { + println("*** netpollopen", fd) + } + lock(&mtxpoll) + netpollwakeup() + + lock(&mtxset) + unlock(&mtxpoll) + + pd.user = uint32(len(pfds)) + pfds = append(pfds, pollfd{fd: int32(fd)}) + pds = append(pds, pd) + unlock(&mtxset) + return 0 +} + +func netpollclose(fd uintptr) int32 { + if pollVerbose { + println("*** netpollclose", fd) + } + lock(&mtxpoll) + netpollwakeup() + + lock(&mtxset) + unlock(&mtxpoll) + + for i := 0; i < len(pfds); i++ { + if pfds[i].fd == int32(fd) { + pfds[i] = pfds[len(pfds)-1] + pfds = pfds[:len(pfds)-1] + + pds[i] = pds[len(pds)-1] + pds[i].user = uint32(i) + pds = pds[:len(pds)-1] + break + } + } + unlock(&mtxset) + return 0 +} + +func netpollarm(pd *pollDesc, mode int) { + if pollVerbose { + println("*** netpollarm", pd.fd, mode) + } + lock(&mtxpoll) + netpollwakeup() + + lock(&mtxset) + unlock(&mtxpoll) + + switch mode { + case 'r': + pfds[pd.user].events |= _POLLIN + case 'w': + pfds[pd.user].events |= _POLLOUT + } + unlock(&mtxset) +} + +//go:nowritebarrierrec +func netpoll(block bool) gList { + timeout := ^uintptr(0) + if !block { + timeout = 0 + return gList{} + } + if pollVerbose { + println("*** netpoll", block) + } +retry: + lock(&mtxpoll) + lock(&mtxset) + pendingUpdates = 0 + unlock(&mtxpoll) + + if pollVerbose { + println("*** netpoll before poll") + } + n, e := poll(&pfds[0], uintptr(len(pfds)), timeout) + if pollVerbose { + println("*** netpoll after poll", n) + } + if n < 0 { + if e != _EINTR { + println("errno=", e, " len(pfds)=", len(pfds)) + throw("poll failed") + } + if pollVerbose { + println("*** poll failed") + } + unlock(&mtxset) + goto retry + } + // Check if some descriptors need to be changed + if n != 0 && pfds[0].revents&(_POLLIN|_POLLHUP|_POLLERR) != 0 { + var b [1]byte + for read(rdwake, unsafe.Pointer(&b[0]), 1) == 1 { + if pollVerbose { + println("*** read 1 byte from pipe") + } + } + // Do not look at the other fds in this case as the mode may have changed + // XXX only additions of flags are made, so maybe it is ok + unlock(&mtxset) + goto retry + } + var toRun gList + for i := 0; i < len(pfds) && n > 0; i++ { + pfd := &pfds[i] + + var mode int32 + if pfd.revents&(_POLLIN|_POLLHUP|_POLLERR) != 0 { + mode += 'r' + pfd.events &= ^_POLLIN + } + if pfd.revents&(_POLLOUT|_POLLHUP|_POLLERR) != 0 { + mode += 'w' + pfd.events &= ^_POLLOUT + } + if mode != 0 { + if pollVerbose { + println("*** netpollready i=", i, "revents=", pfd.revents, "events=", pfd.events, "pd=", pds[i]) + } + netpollready(&toRun, pds[i], mode) + n-- + } + } + unlock(&mtxset) + if block && toRun.empty() { + goto retry + } + if pollVerbose { + println("*** netpoll returning end") + } + return toRun +} diff --git a/src/runtime/os2_aix.go b/src/runtime/os2_aix.go new file mode 100644 index 0000000000..9e26ce23fc --- /dev/null +++ b/src/runtime/os2_aix.go @@ -0,0 +1,479 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file contains main runtime AIX syscalls. +// Pollset syscalls are in netpoll_aix.go. +// The implementation is based on Solaris and Windows. +// Each syscall is made by calling its libc symbol using asmcgocall and asmsyscall6 +// asssembly functions. + +package runtime + +import ( + "unsafe" +) + +// Symbols imported for __start function. + +//go:cgo_import_dynamic libc___n_pthreads __n_pthreads "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libc___mod_init __mod_init "libc.a/shr_64.o" +//go:linkname libc___n_pthreads libc___n_pthread +//go:linkname libc___mod_init libc___mod_init + +var ( + libc___n_pthread, + libc___mod_init libFunc +) + +// Syscalls + +//go:cgo_import_dynamic libc__Errno _Errno "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_clock_gettime clock_gettime "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_close close "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_exit exit "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_getpid getpid "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_kill kill "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_madvise madvise "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_malloc malloc "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_mmap mmap "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_munmap munmap "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_open open "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_pipe pipe "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_raise raise "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_read read "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_sched_yield sched_yield "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_sem_init sem_init "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_sem_post sem_post "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_sem_timedwait sem_timedwait "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_sem_wait sem_wait "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_setitimer setitimer "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_sigaction sigaction "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_sigaltstack sigaltstack "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_sysconf sysconf "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_usleep usleep "libc.a/shr_64.o" +//go:cgo_import_dynamic libc_write write "libc.a/shr_64.o" + +//go:cgo_import_dynamic libpthread___pth_init __pth_init "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libpthread_attr_destroy pthread_attr_destroy "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libpthread_attr_init pthread_attr_init "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libpthread_attr_getstacksize pthread_attr_getstacksize "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libpthread_attr_setstacksize pthread_attr_setstacksize "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libpthread_attr_setdetachstate pthread_attr_setdetachstate "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libpthread_attr_setstackaddr pthread_attr_setstackaddr "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libpthread_create pthread_create "libpthread.a/shr_xpg5_64.o" +//go:cgo_import_dynamic libpthread_sigthreadmask sigthreadmask "libpthread.a/shr_xpg5_64.o" + +//go:linkname libc__Errno libc__Errno +//go:linkname libc_clock_gettime libc_clock_gettime +//go:linkname libc_close libc_close +//go:linkname libc_exit libc_exit +//go:linkname libc_getpid libc_getpid +//go:linkname libc_kill libc_kill +//go:linkname libc_madvise libc_madvise +//go:linkname libc_malloc libc_malloc +//go:linkname libc_mmap libc_mmap +//go:linkname libc_munmap libc_munmap +//go:linkname libc_open libc_open +//go:linkname libc_pipe libc_pipe +//go:linkname libc_raise libc_raise +//go:linkname libc_read libc_read +//go:linkname libc_sched_yield libc_sched_yield +//go:linkname libc_sem_init libc_sem_init +//go:linkname libc_sem_post libc_sem_post +//go:linkname libc_sem_timedwait libc_sem_timedwait +//go:linkname libc_sem_wait libc_sem_wait +//go:linkname libc_setitimer libc_setitimer +//go:linkname libc_sigaction libc_sigaction +//go:linkname libc_sigaltstack libc_sigaltstack +//go:linkname libc_sysconf libc_sysconf +//go:linkname libc_usleep libc_usleep +//go:linkname libc_write libc_write + +//go:linkname libpthread___pth_init libpthread___pth_init +//go:linkname libpthread_attr_destroy libpthread_attr_destroy +//go:linkname libpthread_attr_init libpthread_attr_init +//go:linkname libpthread_attr_getstacksize libpthread_attr_getstacksize +//go:linkname libpthread_attr_setstacksize libpthread_attr_setstacksize +//go:linkname libpthread_attr_setdetachstate libpthread_attr_setdetachstate +//go:linkname libpthread_attr_setstackaddr libpthread_attr_setstackaddr +//go:linkname libpthread_create libpthread_create +//go:linkname libpthread_sigthreadmask libpthread_sigthreadmask + +var ( + //libc + libc__Errno, + libc_clock_gettime, + libc_close, + libc_exit, + libc_getpid, + libc_kill, + libc_madvise, + libc_malloc, + libc_mmap, + libc_munmap, + libc_open, + libc_pipe, + libc_raise, + libc_read, + libc_sched_yield, + libc_sem_init, + libc_sem_post, + libc_sem_timedwait, + libc_sem_wait, + libc_setitimer, + libc_sigaction, + libc_sigaltstack, + libc_sysconf, + libc_usleep, + libc_write, + //libpthread + libpthread___pth_init, + libpthread_attr_destroy, + libpthread_attr_init, + libpthread_attr_getstacksize, + libpthread_attr_setstacksize, + libpthread_attr_setdetachstate, + libpthread_attr_setstackaddr, + libpthread_create, + libpthread_sigthreadmask libFunc +) + +type libFunc uintptr + +// asmsyscall6 calls the libc symbol using a C convention. +// It's defined in sys_aix_ppc64.go. +var asmsyscall6 libFunc + +//go:nowritebarrier +//go:nosplit +func syscall0(fn *libFunc) (r, err uintptr) { + c := &getg().m.libcall + c.fn = uintptr(unsafe.Pointer(fn)) + c.n = 0 + c.args = uintptr(noescape(unsafe.Pointer(&fn))) // it's unused but must be non-nil, otherwise crashes + + asmcgocall(unsafe.Pointer(&asmsyscall6), unsafe.Pointer(c)) + + return c.r1, c.err +} + +//go:nowritebarrier +//go:nosplit +func syscall1(fn *libFunc, a0 uintptr) (r, err uintptr) { + c := &getg().m.libcall + c.fn = uintptr(unsafe.Pointer(fn)) + c.n = 1 + c.args = uintptr(noescape(unsafe.Pointer(&a0))) + + asmcgocall(unsafe.Pointer(&asmsyscall6), unsafe.Pointer(c)) + + return c.r1, c.err +} + +//go:nowritebarrier +//go:nosplit +func syscall2(fn *libFunc, a0, a1 uintptr) (r, err uintptr) { + c := &getg().m.libcall + c.fn = uintptr(unsafe.Pointer(fn)) + c.n = 2 + c.args = uintptr(noescape(unsafe.Pointer(&a0))) + + asmcgocall(unsafe.Pointer(&asmsyscall6), unsafe.Pointer(c)) + + return c.r1, c.err +} + +//go:nowritebarrier +//go:nosplit +func syscall3(fn *libFunc, a0, a1, a2 uintptr) (r, err uintptr) { + c := &getg().m.libcall + c.fn = uintptr(unsafe.Pointer(fn)) + c.n = 3 + c.args = uintptr(noescape(unsafe.Pointer(&a0))) + + asmcgocall(unsafe.Pointer(&asmsyscall6), unsafe.Pointer(c)) + + return c.r1, c.err +} + +//go:nowritebarrier +//go:nosplit +func syscall4(fn *libFunc, a0, a1, a2, a3 uintptr) (r, err uintptr) { + c := &getg().m.libcall + c.fn = uintptr(unsafe.Pointer(fn)) + c.n = 4 + c.args = uintptr(noescape(unsafe.Pointer(&a0))) + + asmcgocall(unsafe.Pointer(&asmsyscall6), unsafe.Pointer(c)) + + return c.r1, c.err +} + +//go:nowritebarrier +//go:nosplit +func syscall5(fn *libFunc, a0, a1, a2, a3, a4 uintptr) (r, err uintptr) { + c := &getg().m.libcall + c.fn = uintptr(unsafe.Pointer(fn)) + c.n = 5 + c.args = uintptr(noescape(unsafe.Pointer(&a0))) + + asmcgocall(unsafe.Pointer(&asmsyscall6), unsafe.Pointer(c)) + + return c.r1, c.err +} + +//go:nowritebarrier +//go:nosplit +func syscall6(fn *libFunc, a0, a1, a2, a3, a4, a5 uintptr) (r, err uintptr) { + c := &getg().m.libcall + c.fn = uintptr(unsafe.Pointer(fn)) + c.n = 6 + c.args = uintptr(noescape(unsafe.Pointer(&a0))) + + asmcgocall(unsafe.Pointer(&asmsyscall6), unsafe.Pointer(c)) + + return c.r1, c.err +} + +//go:nosplit +func exit(code int32) { + syscall1(&libc_exit, uintptr(code)) +} + +//go:nosplit +func write(fd uintptr, p unsafe.Pointer, n int32) int32 { + r, _ := syscall3(&libc_write, uintptr(fd), uintptr(p), uintptr(n)) + return int32(r) + +} + +//go:nosplit +func read(fd int32, p unsafe.Pointer, n int32) int32 { + r, _ := syscall3(&libc_read, uintptr(fd), uintptr(p), uintptr(n)) + return int32(r) +} + +//go:nosplit +func open(name *byte, mode, perm int32) int32 { + r, _ := syscall3(&libc_open, uintptr(unsafe.Pointer(name)), uintptr(mode), uintptr(perm)) + return int32(r) +} + +//go:nosplit +func closefd(fd int32) int32 { + r, _ := syscall1(&libc_close, uintptr(fd)) + return int32(r) +} + +//go:nosplit +func pipe(fd *int32) int32 { + r, _ := syscall1(&libc_pipe, uintptr(unsafe.Pointer(fd))) + return int32(r) +} + +// mmap calls the mmap system call. +// We only pass the lower 32 bits of file offset to the +// assembly routine; the higher bits (if required), should be provided +// by the assembly routine as 0. +// The err result is an OS error code such as ENOMEM. +//go:nosplit +func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) (p unsafe.Pointer, err int) { + r, err0 := syscall6(&libc_mmap, uintptr(addr), uintptr(n), uintptr(prot), uintptr(flags), uintptr(fd), uintptr(off)) + return unsafe.Pointer(r), int(err0) +} + +//go:nosplit +func munmap(addr unsafe.Pointer, n uintptr) { + r, err := syscall2(&libc_munmap, uintptr(addr), uintptr(n)) + if int32(r) == -1 { + println("syscall munmap failed: ", hex(err)) + throw("syscall munmap") + } +} + +//go:nosplit +func madvise(addr unsafe.Pointer, n uintptr, flags int32) { + r, err := syscall3(&libc_madvise, uintptr(addr), uintptr(n), uintptr(flags)) + if int32(r) == -1 { + println("syscall madvise failed: ", hex(err)) + throw("syscall madvise") + } +} + +//go:nosplit +func sigaction(sig uintptr, new, old *sigactiont) { + r, err := syscall3(&libc_sigaction, sig, uintptr(unsafe.Pointer(new)), uintptr(unsafe.Pointer(old))) + if int32(r) == -1 { + println("Sigaction failed for sig: ", sig, " with error:", hex(err)) + throw("syscall sigaction") + } +} + +//go:nosplit +func sigaltstack(new, old *stackt) { + r, err := syscall2(&libc_sigaltstack, uintptr(unsafe.Pointer(new)), uintptr(unsafe.Pointer(old))) + if int32(r) == -1 { + println("syscall sigaltstack failed: ", hex(err)) + throw("syscall sigaltstack") + } +} + +//go:nosplit +func usleep(us uint32) { + r, err := syscall1(&libc_usleep, uintptr(us)) + if int32(r) == -1 { + println("syscall usleep failed: ", hex(err)) + throw("syscall usleep") + } +} + +//go:nosplit +func clock_gettime(clockid int32, tp *timespec) int32 { + r, _ := syscall2(&libc_clock_gettime, uintptr(clockid), uintptr(unsafe.Pointer(tp))) + return int32(r) +} + +//go:nosplit +func setitimer(mode int32, new, old *itimerval) { + r, err := syscall3(&libc_setitimer, uintptr(mode), uintptr(unsafe.Pointer(new)), uintptr(unsafe.Pointer(old))) + if int32(r) == -1 { + println("syscall setitimer failed: ", hex(err)) + throw("syscall setitimer") + } +} + +//go:nosplit +func malloc(size uintptr) unsafe.Pointer { + r, _ := syscall1(&libc_malloc, size) + return unsafe.Pointer(r) +} + +//go:nosplit +func sem_init(sem *semt, pshared int32, value uint32) int32 { + r, _ := syscall3(&libc_sem_init, uintptr(unsafe.Pointer(sem)), uintptr(pshared), uintptr(value)) + return int32(r) +} + +//go:nosplit +func sem_wait(sem *semt) (int32, int32) { + r, err := syscall1(&libc_sem_wait, uintptr(unsafe.Pointer(sem))) + return int32(r), int32(err) +} + +//go:nosplit +func sem_post(sem *semt) int32 { + r, _ := syscall1(&libc_sem_post, uintptr(unsafe.Pointer(sem))) + return int32(r) +} + +//go:nosplit +func sem_timedwait(sem *semt, timeout *timespec) (int32, int32) { + r, err := syscall2(&libc_sem_timedwait, uintptr(unsafe.Pointer(sem)), uintptr(unsafe.Pointer(timeout))) + return int32(r), int32(err) +} + +//go:nosplit +func raise(sig uint32) { + r, err := syscall1(&libc_raise, uintptr(sig)) + if int32(r) == -1 { + println("syscall raise failed: ", hex(err)) + throw("syscall raise") + } +} + +//go:nosplit +func raiseproc(sig uint32) { + pid, err := syscall0(&libc_getpid) + if int32(pid) == -1 { + println("syscall getpid failed: ", hex(err)) + throw("syscall raiseproc") + } + + syscall2(&libc_kill, pid, uintptr(sig)) +} + +func osyield1() + +//go:nosplit +func osyield() { + _g_ := getg() + + // Check the validity of m because we might be called in cgo callback + // path early enough where there isn't a m available yet. + if _g_ != nil && _g_.m != nil { + r, err := syscall0(&libc_sched_yield) + if int32(r) == -1 { + println("syscall osyield failed: ", hex(err)) + throw("syscall osyield") + } + return + } + osyield1() +} + +//go:nosplit +func sysconf(name int32) uintptr { + r, _ := syscall1(&libc_sysconf, uintptr(name)) + if int32(r) == -1 { + throw("syscall sysconf") + } + return r + +} + +// pthread functions returns its error code in the main return value +// Therefore, err returns by syscall means nothing and must not be used + +//go:nosplit +func pthread_attr_destroy(attr *pthread_attr) int32 { + r, _ := syscall1(&libpthread_attr_destroy, uintptr(unsafe.Pointer(attr))) + return int32(r) +} + +//go:nosplit +func pthread_attr_init(attr *pthread_attr) int32 { + r, _ := syscall1(&libpthread_attr_init, uintptr(unsafe.Pointer(attr))) + return int32(r) +} + +//go:nosplit +func pthread_attr_setdetachstate(attr *pthread_attr, state int32) int32 { + r, _ := syscall2(&libpthread_attr_setdetachstate, uintptr(unsafe.Pointer(attr)), uintptr(state)) + return int32(r) +} + +//go:nosplit +func pthread_attr_setstackaddr(attr *pthread_attr, stk unsafe.Pointer) int32 { + r, _ := syscall2(&libpthread_attr_setstackaddr, uintptr(unsafe.Pointer(attr)), uintptr(stk)) + return int32(r) +} + +//go:nosplit +func pthread_attr_getstacksize(attr *pthread_attr, size *uint64) int32 { + r, _ := syscall2(&libpthread_attr_getstacksize, uintptr(unsafe.Pointer(attr)), uintptr(unsafe.Pointer(size))) + return int32(r) +} + +//go:nosplit +func pthread_attr_setstacksize(attr *pthread_attr, size uint64) int32 { + r, _ := syscall2(&libpthread_attr_setstacksize, uintptr(unsafe.Pointer(attr)), uintptr(size)) + return int32(r) +} + +//go:nosplit +func pthread_create(tid *pthread, attr *pthread_attr, fn *funcDescriptor, arg unsafe.Pointer) int32 { + r, _ := syscall4(&libpthread_create, uintptr(unsafe.Pointer(tid)), uintptr(unsafe.Pointer(attr)), uintptr(unsafe.Pointer(fn)), uintptr(arg)) + return int32(r) +} + +// On multi-thread program, sigprocmask must not be called. +// It's replaced by sigthreadmask. +//go:nosplit +func sigprocmask(how int32, new, old *sigset) { + r, err := syscall3(&libpthread_sigthreadmask, uintptr(how), uintptr(unsafe.Pointer(new)), uintptr(unsafe.Pointer(old))) + if int32(r) != 0 { + println("syscall sigthreadmask failed: ", hex(err)) + throw("syscall sigthreadmask") + } +} diff --git a/src/runtime/os_aix.go b/src/runtime/os_aix.go new file mode 100644 index 0000000000..31590f22d8 --- /dev/null +++ b/src/runtime/os_aix.go @@ -0,0 +1,262 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build aix + +package runtime + +import ( + "unsafe" +) + +const ( + threadStackSize = 0x100000 // size of a thread stack allocated by OS +) + +// funcDescriptor is a structure representing a function descriptor +// A variable with this type is always created in assembler +type funcDescriptor struct { + fn uintptr + toc uintptr + envPointer uintptr // unused in Golang +} + +type mOS struct { + waitsema uintptr // semaphore for parking on locks + perrno uintptr // pointer to tls errno +} + +//go:nosplit +func semacreate(mp *m) { + if mp.waitsema != 0 { + return + } + + var sem *semt + + // Call libc's malloc rather than malloc. This will + // allocate space on the C heap. We can't call mallocgc + // here because it could cause a deadlock. + sem = (*semt)(malloc(unsafe.Sizeof(*sem))) + if sem_init(sem, 0, 0) != 0 { + throw("sem_init") + } + mp.waitsema = uintptr(unsafe.Pointer(sem)) +} + +//go:nosplit +func semasleep(ns int64) int32 { + _m_ := getg().m + if ns >= 0 { + var ts timespec + + if clock_gettime(_CLOCK_REALTIME, &ts) != 0 { + throw("clock_gettime") + } + ts.tv_sec += ns / 1e9 + ts.tv_nsec += ns % 1e9 + if ts.tv_nsec >= 1e9 { + ts.tv_sec++ + ts.tv_nsec -= 1e9 + } + + if r, err := sem_timedwait((*semt)(unsafe.Pointer(_m_.waitsema)), &ts); r != 0 { + if err == _ETIMEDOUT || err == _EAGAIN || err == _EINTR { + return -1 + } + println("sem_timedwait err ", err, " ts.tv_sec ", ts.tv_sec, " ts.tv_nsec ", ts.tv_nsec, " ns ", ns, " id ", _m_.id) + throw("sem_timedwait") + } + return 0 + } + for { + r1, err := sem_wait((*semt)(unsafe.Pointer(_m_.waitsema))) + if r1 == 0 { + break + } + if err == _EINTR { + continue + } + throw("sem_wait") + } + return 0 +} + +//go:nosplit +func semawakeup(mp *m) { + if sem_post((*semt)(unsafe.Pointer(mp.waitsema))) != 0 { + throw("sem_post") + } +} + +func osinit() { + ncpu = int32(sysconf(__SC_NPROCESSORS_ONLN)) + physPageSize = sysconf(__SC_PAGE_SIZE) +} + +// Ms related functions +func mpreinit(mp *m) { + mp.gsignal = malg(32 * 1024) // AIX wants >= 8K + mp.gsignal.m = mp +} + +// errno address must be retrieved by calling _Errno libc function. +// This will return a pointer to errno +func miniterrno() { + mp := getg().m + r, _ := syscall0(&libc__Errno) + mp.perrno = r + +} + +func minit() { + miniterrno() + minitSignals() +} + +func unminit() { + unminitSignals() +} + +// tstart is a function descriptor to _tstart defined in assembly. +var tstart funcDescriptor + +func newosproc(mp *m) { + var ( + attr pthread_attr + oset sigset + tid pthread + ) + + if pthread_attr_init(&attr) != 0 { + throw("pthread_attr_init") + } + + if pthread_attr_setstacksize(&attr, threadStackSize) != 0 { + throw("pthread_attr_getstacksize") + } + + if pthread_attr_setdetachstate(&attr, _PTHREAD_CREATE_DETACHED) != 0 { + throw("pthread_attr_setdetachstate") + } + + // Disable signals during create, so that the new thread starts + // with signals disabled. It will enable them in minit. + sigprocmask(_SIG_SETMASK, &sigset_all, &oset) + var ret int32 + for tries := 0; tries < 20; tries++ { + // pthread_create can fail with EAGAIN for no reasons + // but it will be ok if it retries. + ret = pthread_create(&tid, &attr, &tstart, unsafe.Pointer(mp)) + if ret != _EAGAIN { + break + } + usleep(uint32(tries+1) * 1000) // Milliseconds. + } + sigprocmask(_SIG_SETMASK, &oset, nil) + if ret != 0 { + print("runtime: failed to create new OS thread (have ", mcount(), " already; errno=", ret, ")\n") + if ret == _EAGAIN { + println("runtime: may need to increase max user processes (ulimit -u)") + } + throw("newosproc") + } + +} + +func exitThread(wait *uint32) { + // We should never reach exitThread on AIX because we let + // libc clean up threads. + throw("exitThread") +} + +var urandom_dev = []byte("/dev/urandom\x00") + +//go:nosplit +func getRandomData(r []byte) { + fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0) + n := read(fd, unsafe.Pointer(&r[0]), int32(len(r))) + closefd(fd) + extendRandom(r, int(n)) +} + +func goenvs() { + goenvs_unix() +} + +/* SIGNAL */ + +const ( + _NSIG = 256 +) + +// sigtramp is a function descriptor to _sigtramp defined in assembly +var sigtramp funcDescriptor + +//go:nosplit +//go:nowritebarrierrec +func setsig(i uint32, fn uintptr) { + var sa sigactiont + sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _SA_RESTART + sa.sa_mask = sigset_all + if fn == funcPC(sighandler) { + fn = uintptr(unsafe.Pointer(&sigtramp)) + } + sa.sa_handler = fn + sigaction(uintptr(i), &sa, nil) + +} + +//go:nosplit +//go:nowritebarrierrec +func setsigstack(i uint32) { + throw("Not yet implemented\n") +} + +//go:nosplit +//go:nowritebarrierrec +func getsig(i uint32) uintptr { + var sa sigactiont + sigaction(uintptr(i), nil, &sa) + return sa.sa_handler +} + +// setSignaltstackSP sets the ss_sp field of a stackt. +//go:nosplit +func setSignalstackSP(s *stackt, sp uintptr) { + *(*uintptr)(unsafe.Pointer(&s.ss_sp)) = sp +} + +func (c *sigctxt) fixsigcode(sig uint32) { +} + +func sigaddset(mask *sigset, i int) { + (*mask)[(i-1)/64] |= 1 << ((uint32(i) - 1) & 63) +} + +func sigdelset(mask *sigset, i int) { + (*mask)[(i-1)/64] &^= 1 << ((uint32(i) - 1) & 63) +} + +const ( + _CLOCK_REALTIME = 9 + _CLOCK_MONOTONIC = 10 +) + +//go:nosplit +func nanotime() int64 { + tp := ×pec{} + if clock_gettime(_CLOCK_REALTIME, tp) != 0 { + throw("syscall clock_gettime failed") + } + return tp.tv_sec*1000000000 + tp.tv_nsec +} + +func walltime() (sec int64, nsec int32) { + ts := ×pec{} + if clock_gettime(_CLOCK_REALTIME, ts) != 0 { + throw("syscall clock_gettime failed") + } + return ts.tv_sec, int32(ts.tv_nsec) +} diff --git a/src/runtime/os_darwin.go b/src/runtime/os_darwin.go index d2144edf2e..26b02820cd 100644 --- a/src/runtime/os_darwin.go +++ b/src/runtime/os_darwin.go @@ -34,6 +34,10 @@ func semacreate(mp *m) { //go:nosplit func semasleep(ns int64) int32 { + var start int64 + if ns >= 0 { + start = nanotime() + } mp := getg().m pthread_mutex_lock(&mp.mutex) for { @@ -43,8 +47,13 @@ func semasleep(ns int64) int32 { return 0 } if ns >= 0 { + spent := nanotime() - start + if spent >= ns { + pthread_mutex_unlock(&mp.mutex) + return -1 + } var t timespec - t.set_nsec(ns) + t.set_nsec(ns - spent) err := pthread_cond_timedwait_relative_np(&mp.cond, &mp.mutex, &t) if err == _ETIMEDOUT { pthread_mutex_unlock(&mp.mutex) diff --git a/src/runtime/os_nacl.go b/src/runtime/os_nacl.go index 23ab03b953..ac7bf69582 100644 --- a/src/runtime/os_nacl.go +++ b/src/runtime/os_nacl.go @@ -197,23 +197,23 @@ func semacreate(mp *m) { //go:nosplit func semasleep(ns int64) int32 { var ret int32 - systemstack(func() { _g_ := getg() if nacl_mutex_lock(_g_.m.waitsemalock) < 0 { throw("semasleep") } - + var ts timespec + if ns >= 0 { + end := ns + nanotime() + ts.tv_sec = end / 1e9 + ts.tv_nsec = int32(end % 1e9) + } for _g_.m.waitsemacount == 0 { if ns < 0 { if nacl_cond_wait(_g_.m.waitsema, _g_.m.waitsemalock) < 0 { throw("semasleep") } } else { - var ts timespec - end := ns + nanotime() - ts.tv_sec = end / 1e9 - ts.tv_nsec = int32(end % 1e9) r := nacl_cond_timed_wait_abs(_g_.m.waitsema, _g_.m.waitsemalock, &ts) if r == -_ETIMEDOUT { nacl_mutex_unlock(_g_.m.waitsemalock) diff --git a/src/runtime/os_netbsd.go b/src/runtime/os_netbsd.go index a9bf407a36..7deab3ed03 100644 --- a/src/runtime/os_netbsd.go +++ b/src/runtime/os_netbsd.go @@ -126,15 +126,9 @@ func semacreate(mp *m) { //go:nosplit func semasleep(ns int64) int32 { _g_ := getg() - - // Compute sleep deadline. - var tsp *timespec - var ts timespec + var deadline int64 if ns >= 0 { - var nsec int32 - ts.set_sec(timediv(ns, 1000000000, &nsec)) - ts.set_nsec(nsec) - tsp = &ts + deadline = nanotime() + ns } for { @@ -147,18 +141,21 @@ func semasleep(ns int64) int32 { } // Sleep until unparked by semawakeup or timeout. + var tsp *timespec + var ts timespec + if ns >= 0 { + wait := deadline - nanotime() + if wait <= 0 { + return -1 + } + var nsec int32 + ts.set_sec(timediv(wait, 1000000000, &nsec)) + ts.set_nsec(nsec) + tsp = &ts + } ret := lwp_park(_CLOCK_MONOTONIC, _TIMER_RELTIME, tsp, 0, unsafe.Pointer(&_g_.m.waitsemacount), nil) if ret == _ETIMEDOUT { return -1 - } else if ret == _EINTR && ns >= 0 { - // Avoid sleeping forever if we keep getting - // interrupted (for example by the profiling - // timer). It would be if tsp upon return had the - // remaining time to sleep, but this is good enough. - var nsec int32 - ns /= 2 - ts.set_sec(timediv(ns, 1000000000, &nsec)) - ts.set_nsec(nsec) } } } diff --git a/src/runtime/os_windows.go b/src/runtime/os_windows.go index 5607bf95c1..03dd95bf17 100644 --- a/src/runtime/os_windows.go +++ b/src/runtime/os_windows.go @@ -43,6 +43,7 @@ const ( //go:cgo_import_dynamic runtime._SetWaitableTimer SetWaitableTimer%6 "kernel32.dll" //go:cgo_import_dynamic runtime._SuspendThread SuspendThread%1 "kernel32.dll" //go:cgo_import_dynamic runtime._SwitchToThread SwitchToThread%0 "kernel32.dll" +//go:cgo_import_dynamic runtime._TlsAlloc TlsAlloc%0 "kernel32.dll" //go:cgo_import_dynamic runtime._VirtualAlloc VirtualAlloc%4 "kernel32.dll" //go:cgo_import_dynamic runtime._VirtualFree VirtualFree%3 "kernel32.dll" //go:cgo_import_dynamic runtime._VirtualQuery VirtualQuery%3 "kernel32.dll" @@ -91,6 +92,7 @@ var ( _SetWaitableTimer, _SuspendThread, _SwitchToThread, + _TlsAlloc, _VirtualAlloc, _VirtualFree, _VirtualQuery, @@ -856,18 +858,38 @@ func profileloop() var profiletimer uintptr -func profilem(mp *m) { +func profilem(mp *m, thread uintptr) { var r *context rbuf := make([]byte, unsafe.Sizeof(*r)+15) - tls := &mp.tls[0] - gp := *((**g)(unsafe.Pointer(tls))) - // align Context to 16 bytes r = (*context)(unsafe.Pointer((uintptr(unsafe.Pointer(&rbuf[15]))) &^ 15)) r.contextflags = _CONTEXT_CONTROL - stdcall2(_GetThreadContext, mp.thread, uintptr(unsafe.Pointer(r))) - sigprof(r.ip(), r.sp(), 0, gp, mp) + stdcall2(_GetThreadContext, thread, uintptr(unsafe.Pointer(r))) + + var gp *g + switch GOARCH { + default: + panic("unsupported architecture") + case "arm": + // TODO(jordanrh1): this is incorrect when Go is executing + // on the system or signal stacks because curg returns + // the current user g. The true g is stored in thread + // local storage, which we cannot access from another CPU. + // We cannot pull R10 from the thread context because + // it might be executing C code, in which case R10 + // would not be g. + gp = mp.curg + case "386", "amd64": + tls := &mp.tls[0] + gp = *((**g)(unsafe.Pointer(tls))) + } + + if gp == nil { + sigprofNonGoPC(r.ip()) + } else { + sigprof(r.ip(), r.sp(), 0, gp, mp) + } } func profileloop1(param uintptr) uint32 { @@ -884,9 +906,16 @@ func profileloop1(param uintptr) uint32 { if thread == 0 || mp.profilehz == 0 || mp.blocked { continue } - stdcall1(_SuspendThread, thread) + // mp may exit between the load above and the + // SuspendThread, so be careful. + if int32(stdcall1(_SuspendThread, thread)) == -1 { + // The thread no longer exists. + continue + } if mp.profilehz != 0 && !mp.blocked { - profilem(mp) + // Pass the thread handle in case mp + // was in the process of shutting down. + profilem(mp, thread) } stdcall1(_ResumeThread, thread) } diff --git a/src/runtime/os_windows_arm.go b/src/runtime/os_windows_arm.go new file mode 100644 index 0000000000..3115f7241d --- /dev/null +++ b/src/runtime/os_windows_arm.go @@ -0,0 +1,18 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package runtime + +//go:nosplit +func cputicks() int64 { + return nanotime() +} + +func checkgoarm() { + if goarm < 7 { + print("Need atomic synchronization instructions, coprocessor ", + "access instructions. Recompile using GOARM=7.\n") + exit(1) + } +} diff --git a/src/runtime/pprof/internal/profile/profile.go b/src/runtime/pprof/internal/profile/profile.go index 64c3e3f054..863bd403a4 100644 --- a/src/runtime/pprof/internal/profile/profile.go +++ b/src/runtime/pprof/internal/profile/profile.go @@ -200,7 +200,7 @@ var libRx = regexp.MustCompile(`([.]so$|[.]so[._][0-9]+)`) // first. func (p *Profile) setMain() { for i := 0; i < len(p.Mapping); i++ { - file := strings.TrimSpace(strings.Replace(p.Mapping[i].File, "(deleted)", "", -1)) + file := strings.TrimSpace(strings.ReplaceAll(p.Mapping[i].File, "(deleted)", "")) if len(file) == 0 { continue } diff --git a/src/runtime/pprof/pprof_test.go b/src/runtime/pprof/pprof_test.go index 126ba50054..593924183f 100644 --- a/src/runtime/pprof/pprof_test.go +++ b/src/runtime/pprof/pprof_test.go @@ -602,7 +602,7 @@ func TestBlockProfile(t *testing.T) { } for _, test := range tests { - if !regexp.MustCompile(strings.Replace(test.re, "\t", "\t+", -1)).MatchString(prof) { + if !regexp.MustCompile(strings.ReplaceAll(test.re, "\t", "\t+")).MatchString(prof) { t.Errorf("Bad %v entry, expect:\n%v\ngot:\n%v", test.name, test.re, prof) } } diff --git a/src/runtime/pprof/proto.go b/src/runtime/pprof/proto.go index cbd0b83376..bd5c8f7afc 100644 --- a/src/runtime/pprof/proto.go +++ b/src/runtime/pprof/proto.go @@ -524,6 +524,14 @@ func parseProcSelfMaps(data []byte, addMapping func(lo, hi, offset uint64, file, continue } file := string(line) + + // Trim deleted file marker. + deletedStr := " (deleted)" + deletedLen := len(deletedStr) + if len(file) >= deletedLen && file[len(file)-deletedLen:] == deletedStr { + file = file[:len(file)-deletedLen] + } + if len(inode) == 1 && inode[0] == '0' && file == "" { // Huge-page text mappings list the initial fragment of // mapped but unpopulated memory as being inode 0. diff --git a/src/runtime/pprof/proto_test.go b/src/runtime/pprof/proto_test.go index 76bd46da02..4452d51231 100644 --- a/src/runtime/pprof/proto_test.go +++ b/src/runtime/pprof/proto_test.go @@ -216,24 +216,89 @@ c000000000-c000036000 rw-p 00000000 00:00 0 07000000 07093000 06c00000 /path/to/gobench_server_main ` +var profSelfMapsTestsWithDeleted = ` +00400000-0040b000 r-xp 00000000 fc:01 787766 /bin/cat (deleted) +0060a000-0060b000 r--p 0000a000 fc:01 787766 /bin/cat (deleted) +0060b000-0060c000 rw-p 0000b000 fc:01 787766 /bin/cat (deleted) +014ab000-014cc000 rw-p 00000000 00:00 0 [heap] +7f7d76af8000-7f7d7797c000 r--p 00000000 fc:01 1318064 /usr/lib/locale/locale-archive +7f7d7797c000-7f7d77b36000 r-xp 00000000 fc:01 1180226 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77b36000-7f7d77d36000 ---p 001ba000 fc:01 1180226 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77d36000-7f7d77d3a000 r--p 001ba000 fc:01 1180226 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77d3a000-7f7d77d3c000 rw-p 001be000 fc:01 1180226 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77d3c000-7f7d77d41000 rw-p 00000000 00:00 0 +7f7d77d41000-7f7d77d64000 r-xp 00000000 fc:01 1180217 /lib/x86_64-linux-gnu/ld-2.19.so +7f7d77f3f000-7f7d77f42000 rw-p 00000000 00:00 0 +7f7d77f61000-7f7d77f63000 rw-p 00000000 00:00 0 +7f7d77f63000-7f7d77f64000 r--p 00022000 fc:01 1180217 /lib/x86_64-linux-gnu/ld-2.19.so +7f7d77f64000-7f7d77f65000 rw-p 00023000 fc:01 1180217 /lib/x86_64-linux-gnu/ld-2.19.so +7f7d77f65000-7f7d77f66000 rw-p 00000000 00:00 0 +7ffc342a2000-7ffc342c3000 rw-p 00000000 00:00 0 [stack] +7ffc34343000-7ffc34345000 r-xp 00000000 00:00 0 [vdso] +ffffffffff600000-ffffffffff601000 r-xp 00000090 00:00 0 [vsyscall] +-> +00400000 0040b000 00000000 /bin/cat +7f7d7797c000 7f7d77b36000 00000000 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77d41000 7f7d77d64000 00000000 /lib/x86_64-linux-gnu/ld-2.19.so +7ffc34343000 7ffc34345000 00000000 [vdso] +ffffffffff600000 ffffffffff601000 00000090 [vsyscall] + +00400000-0040b000 r-xp 00000000 fc:01 787766 /bin/cat with space +0060a000-0060b000 r--p 0000a000 fc:01 787766 /bin/cat with space +0060b000-0060c000 rw-p 0000b000 fc:01 787766 /bin/cat with space +014ab000-014cc000 rw-p 00000000 00:00 0 [heap] +7f7d76af8000-7f7d7797c000 r--p 00000000 fc:01 1318064 /usr/lib/locale/locale-archive +7f7d7797c000-7f7d77b36000 r-xp 00000000 fc:01 1180226 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77b36000-7f7d77d36000 ---p 001ba000 fc:01 1180226 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77d36000-7f7d77d3a000 r--p 001ba000 fc:01 1180226 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77d3a000-7f7d77d3c000 rw-p 001be000 fc:01 1180226 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77d3c000-7f7d77d41000 rw-p 00000000 00:00 0 +7f7d77d41000-7f7d77d64000 r-xp 00000000 fc:01 1180217 /lib/x86_64-linux-gnu/ld-2.19.so +7f7d77f3f000-7f7d77f42000 rw-p 00000000 00:00 0 +7f7d77f61000-7f7d77f63000 rw-p 00000000 00:00 0 +7f7d77f63000-7f7d77f64000 r--p 00022000 fc:01 1180217 /lib/x86_64-linux-gnu/ld-2.19.so +7f7d77f64000-7f7d77f65000 rw-p 00023000 fc:01 1180217 /lib/x86_64-linux-gnu/ld-2.19.so +7f7d77f65000-7f7d77f66000 rw-p 00000000 00:00 0 +7ffc342a2000-7ffc342c3000 rw-p 00000000 00:00 0 [stack] +7ffc34343000-7ffc34345000 r-xp 00000000 00:00 0 [vdso] +ffffffffff600000-ffffffffff601000 r-xp 00000090 00:00 0 [vsyscall] +-> +00400000 0040b000 00000000 /bin/cat with space +7f7d7797c000 7f7d77b36000 00000000 /lib/x86_64-linux-gnu/libc-2.19.so +7f7d77d41000 7f7d77d64000 00000000 /lib/x86_64-linux-gnu/ld-2.19.so +7ffc34343000 7ffc34345000 00000000 [vdso] +ffffffffff600000 ffffffffff601000 00000090 [vsyscall] +` + func TestProcSelfMaps(t *testing.T) { - for tx, tt := range strings.Split(profSelfMapsTests, "\n\n") { - i := strings.Index(tt, "->\n") - if i < 0 { - t.Fatal("malformed test case") - } - in, out := tt[:i], tt[i+len("->\n"):] - if len(out) > 0 && out[len(out)-1] != '\n' { - out += "\n" - } - var buf bytes.Buffer - parseProcSelfMaps([]byte(in), func(lo, hi, offset uint64, file, buildID string) { - fmt.Fprintf(&buf, "%08x %08x %08x %s\n", lo, hi, offset, file) - }) - if buf.String() != out { - t.Errorf("#%d: have:\n%s\nwant:\n%s\n%q\n%q", tx, buf.String(), out, buf.String(), out) + + f := func(t *testing.T, input string) { + for tx, tt := range strings.Split(input, "\n\n") { + i := strings.Index(tt, "->\n") + if i < 0 { + t.Fatal("malformed test case") + } + in, out := tt[:i], tt[i+len("->\n"):] + if len(out) > 0 && out[len(out)-1] != '\n' { + out += "\n" + } + var buf bytes.Buffer + parseProcSelfMaps([]byte(in), func(lo, hi, offset uint64, file, buildID string) { + fmt.Fprintf(&buf, "%08x %08x %08x %s\n", lo, hi, offset, file) + }) + if buf.String() != out { + t.Errorf("#%d: have:\n%s\nwant:\n%s\n%q\n%q", tx, buf.String(), out, buf.String(), out) + } } } + + t.Run("Normal", func(t *testing.T) { + f(t, profSelfMapsTests) + }) + + t.Run("WithDeletedFile", func(t *testing.T) { + f(t, profSelfMapsTestsWithDeleted) + }) } // TestMapping checkes the mapping section of CPU profiles diff --git a/src/runtime/proc.go b/src/runtime/proc.go index 73b4a1d9d6..acfdc8472e 100644 --- a/src/runtime/proc.go +++ b/src/runtime/proc.go @@ -254,7 +254,7 @@ func forcegchelper() { println("GC forced") } // Time-triggered, fully concurrent. - gcStart(gcBackgroundMode, gcTrigger{kind: gcTriggerTime, now: nanotime()}) + gcStart(gcTrigger{kind: gcTriggerTime, now: nanotime()}) } } @@ -663,59 +663,6 @@ func ready(gp *g, traceskip int, next bool) { } } -func gcprocs() int32 { - // Figure out how many CPUs to use during GC. - // Limited by gomaxprocs, number of actual CPUs, and MaxGcproc. - lock(&sched.lock) - n := gomaxprocs - if n > ncpu { - n = ncpu - } - if n > _MaxGcproc { - n = _MaxGcproc - } - if n > sched.nmidle+1 { // one M is currently running - n = sched.nmidle + 1 - } - unlock(&sched.lock) - return n -} - -func needaddgcproc() bool { - lock(&sched.lock) - n := gomaxprocs - if n > ncpu { - n = ncpu - } - if n > _MaxGcproc { - n = _MaxGcproc - } - n -= sched.nmidle + 1 // one M is currently running - unlock(&sched.lock) - return n > 0 -} - -func helpgc(nproc int32) { - _g_ := getg() - lock(&sched.lock) - pos := 0 - for n := int32(1); n < nproc; n++ { // one M is currently running - if allp[pos].mcache == _g_.m.mcache { - pos++ - } - mp := mget() - if mp == nil { - throw("gcprocs inconsistency") - } - mp.helpgc = n - mp.p.set(allp[pos]) - mp.mcache = allp[pos].mcache - pos++ - notewakeup(&mp.park) - } - unlock(&sched.lock) -} - // freezeStopWait is a large value that freezetheworld sets // sched.stopwait to in order to request that all Gs permanently stop. const freezeStopWait = 0x7fffffff @@ -1132,11 +1079,6 @@ func stopTheWorldWithSema() { } } -func mhelpgc() { - _g_ := getg() - _g_.m.helpgc = -1 -} - func startTheWorldWithSema(emitTraceEvent bool) int64 { _g_ := getg() @@ -1145,7 +1087,6 @@ func startTheWorldWithSema(emitTraceEvent bool) int64 { list := netpoll(false) // non-blocking injectglist(&list) } - add := needaddgcproc() lock(&sched.lock) procs := gomaxprocs @@ -1175,7 +1116,6 @@ func startTheWorldWithSema(emitTraceEvent bool) int64 { } else { // Start M to run P. Do not start another M below. newm(nil, p) - add = false } } @@ -1192,16 +1132,6 @@ func startTheWorldWithSema(emitTraceEvent bool) int64 { wakep() } - if add { - // If GC could have used another helper proc, start one now, - // in the hope that it will be available next time. - // It would have been even better to start it before the collection, - // but doing so requires allocating memory, so it's tricky to - // coordinate. This lazy approach works out in practice: - // we don't mind if the first couple gc rounds don't have quite - // the maximum number of procs. - newm(mhelpgc, nil) - } _g_.m.locks-- if _g_.m.locks == 0 && _g_.preempt { // restore the preemption request in case we've cleared it in newstack _g_.stackguard0 = stackPreempt @@ -1242,8 +1172,8 @@ func mstart() { mstart1() // Exit this thread. - if GOOS == "windows" || GOOS == "solaris" || GOOS == "plan9" || GOOS == "darwin" { - // Window, Solaris, Darwin and Plan 9 always system-allocate + if GOOS == "windows" || GOOS == "solaris" || GOOS == "plan9" || GOOS == "darwin" || GOOS == "aix" { + // Window, Solaris, Darwin, AIX and Plan 9 always system-allocate // the stack, but put it in _g_.stack before mstart, // so the logic above hasn't set osStack yet. osStack = true @@ -1276,10 +1206,7 @@ func mstart1() { fn() } - if _g_.m.helpgc != 0 { - _g_.m.helpgc = 0 - stopm() - } else if _g_.m != &m0 { + if _g_.m != &m0 { acquirep(_g_.m.nextp.ptr()) _g_.m.nextp = 0 } @@ -2003,21 +1930,11 @@ func stopm() { throw("stopm spinning") } -retry: lock(&sched.lock) mput(_g_.m) unlock(&sched.lock) notesleep(&_g_.m.park) noteclear(&_g_.m.park) - if _g_.m.helpgc != 0 { - // helpgc() set _g_.m.p and _g_.m.mcache, so we have a P. - gchelper() - // Undo the effects of helpgc(). - _g_.m.helpgc = 0 - _g_.m.mcache = nil - _g_.m.p = 0 - goto retry - } acquirep(_g_.m.nextp.ptr()) _g_.m.nextp = 0 } @@ -2615,6 +2532,23 @@ top: resetspinning() } + if sched.disable.user && !schedEnabled(gp) { + // Scheduling of this goroutine is disabled. Put it on + // the list of pending runnable goroutines for when we + // re-enable user scheduling and look again. + lock(&sched.lock) + if schedEnabled(gp) { + // Something re-enabled scheduling while we + // were acquiring the lock. + unlock(&sched.lock) + } else { + sched.disable.runnable.pushBack(gp) + sched.disable.n++ + unlock(&sched.lock) + goto top + } + } + if gp.lockedm != 0 { // Hands off own p to the locked m, // then blocks waiting for a new p. @@ -2730,7 +2664,7 @@ func goexit0(gp *g) { _g_ := getg() casgstatus(gp, _Grunning, _Gdead) - if isSystemGoroutine(gp) { + if isSystemGoroutine(gp, false) { atomic.Xadd(&sched.ngsys, -1) } gp.m = nil @@ -3033,6 +2967,12 @@ func exitsyscall() { _g_.stackguard0 = _g_.stack.lo + _StackGuard } _g_.throwsplit = false + + if sched.disable.user && !schedEnabled(_g_) { + // Scheduling of this goroutine is disabled. + Gosched() + } + return } @@ -3168,7 +3108,10 @@ func exitsyscall0(gp *g) { casgstatus(gp, _Gsyscall, _Grunnable) dropg() lock(&sched.lock) - _p_ := pidleget() + var _p_ *p + if schedEnabled(_g_) { + _p_ = pidleget() + } if _p_ == nil { globrunqput(gp) } else if atomic.Load(&sched.sysmonwait) != 0 { @@ -3381,7 +3324,7 @@ func newproc1(fn *funcval, argp *uint8, narg int32, callergp *g, callerpc uintpt if _g_.m.curg != nil { newg.labels = _g_.m.curg.labels } - if isSystemGoroutine(newg) { + if isSystemGoroutine(newg, false) { atomic.Xadd(&sched.ngsys, +1) } newg.gcscanvalid = false @@ -3831,7 +3774,7 @@ func sigprof(pc, sp, lr uintptr, gp *g, mp *m) { pc = funcPC(_ExternalCode) + sys.PCQuantum } stk[0] = pc - if mp.preemptoff != "" || mp.helpgc != 0 { + if mp.preemptoff != "" { stk[1] = funcPC(_GC) + sys.PCQuantum } else { stk[1] = funcPC(_System) + sys.PCQuantum @@ -4093,6 +4036,7 @@ func procresize(nprocs int32) *p { if _g_.m.p != 0 && _g_.m.p.ptr().id < nprocs { // continue to use the current P _g_.m.p.ptr().status = _Prunning + _g_.m.p.ptr().mcache.prepareForSweep() } else { // release the current P and acquire allp[0] if _g_.m.p != 0 { @@ -4143,6 +4087,10 @@ func acquirep(_p_ *p) { _g_ := getg() _g_.m.mcache = _p_.mcache + // Perform deferred mcache flush before this P can allocate + // from a potentially stale mcache. + _p_.mcache.prepareForSweep() + if trace.enabled { traceProcStart() } @@ -4244,7 +4192,7 @@ func checkdead() { lock(&allglock) for i := 0; i < len(allgs); i++ { gp := allgs[i] - if isSystemGoroutine(gp) { + if isSystemGoroutine(gp, false) { continue } s := readgstatus(gp) @@ -4603,7 +4551,7 @@ func schedtrace(detailed bool) { if lockedg != nil { id3 = lockedg.goid } - print(" M", mp.id, ": p=", id1, " curg=", id2, " mallocing=", mp.mallocing, " throwing=", mp.throwing, " preemptoff=", mp.preemptoff, ""+" locks=", mp.locks, " dying=", mp.dying, " helpgc=", mp.helpgc, " spinning=", mp.spinning, " blocked=", mp.blocked, " lockedg=", id3, "\n") + print(" M", mp.id, ": p=", id1, " curg=", id2, " mallocing=", mp.mallocing, " throwing=", mp.throwing, " preemptoff=", mp.preemptoff, ""+" locks=", mp.locks, " dying=", mp.dying, " spinning=", mp.spinning, " blocked=", mp.blocked, " lockedg=", id3, "\n") } lock(&allglock) @@ -4625,6 +4573,40 @@ func schedtrace(detailed bool) { unlock(&sched.lock) } +// schedEnableUser enables or disables the scheduling of user +// goroutines. +// +// This does not stop already running user goroutines, so the caller +// should first stop the world when disabling user goroutines. +func schedEnableUser(enable bool) { + lock(&sched.lock) + if sched.disable.user == !enable { + unlock(&sched.lock) + return + } + sched.disable.user = !enable + if enable { + n := sched.disable.n + sched.disable.n = 0 + globrunqputbatch(&sched.disable.runnable, n) + unlock(&sched.lock) + for ; n != 0 && sched.npidle != 0; n-- { + startm(nil, false) + } + } else { + unlock(&sched.lock) + } +} + +// schedEnabled returns whether gp should be scheduled. It returns +// false is scheduling of gp is disabled. +func schedEnabled(gp *g) bool { + if sched.disable.user { + return isSystemGoroutine(gp, true) + } + return true +} + // Put mp on midle list. // Sched must be locked. // May run during STW, so write barriers are not allowed. diff --git a/src/runtime/race/testdata/chan_test.go b/src/runtime/race/testdata/chan_test.go index 7f349c42ed..60e55ed66a 100644 --- a/src/runtime/race/testdata/chan_test.go +++ b/src/runtime/race/testdata/chan_test.go @@ -577,18 +577,32 @@ func TestRaceChanItselfCap(t *testing.T) { <-compl } -func TestRaceChanCloseLen(t *testing.T) { - v := 0 - _ = v +func TestNoRaceChanCloseLen(t *testing.T) { c := make(chan int, 10) - c <- 0 + r := make(chan int, 10) + go func() { + r <- len(c) + }() go func() { - v = 1 close(c) + r <- 0 }() - time.Sleep(1e7) - _ = len(c) - v = 2 + <-r + <-r +} + +func TestNoRaceChanCloseCap(t *testing.T) { + c := make(chan int, 10) + r := make(chan int, 10) + go func() { + r <- cap(c) + }() + go func() { + close(c) + r <- 0 + }() + <-r + <-r } func TestRaceChanCloseSend(t *testing.T) { diff --git a/src/runtime/rt0_aix_ppc64.s b/src/runtime/rt0_aix_ppc64.s new file mode 100644 index 0000000000..0e3d582809 --- /dev/null +++ b/src/runtime/rt0_aix_ppc64.s @@ -0,0 +1,40 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "textflag.h" + +// _rt0_ppc64_aix is a function descriptor of the entrypoint function +// __start. This name is needed by cmd/link. +DATA _rt0_ppc64_aix+0(SB)/8, $__start<>(SB) +DATA _rt0_ppc64_aix+8(SB)/8, $TOC(SB) +GLOBL _rt0_ppc64_aix(SB), NOPTR, $16 + + +// The starting function must return in the loader to +// initialise some librairies, especially libthread which +// creates the main thread and adds the TLS in R13 +// R19 contains a function descriptor to the loader function +// which needs to be called. +// This code is similar to the __start function in C +TEXT __start<>(SB),NOSPLIT,$-8 + XOR R0, R0 + MOVD $libc___n_pthreads(SB), R4 + MOVD 0(R4), R4 + MOVD $libc___mod_init(SB), R5 + MOVD 0(R5), R5 + MOVD 0(R19), R0 + MOVD R2, 40(R1) + MOVD 8(R19), R2 + MOVD R18, R3 + MOVD R0, CTR + BL (CTR) // Return to AIX loader + + // Launch rt0_go + MOVD 40(R1), R2 + MOVD R14, R3 // argc + MOVD R15, R4 // argv + MOVD $runtime·rt0_go(SB), R12 + MOVD R12, CTR + BR (CTR) + diff --git a/src/runtime/rt0_linux_ppc64le.s b/src/runtime/rt0_linux_ppc64le.s index 73b9ae392d..54ea9d58f7 100644 --- a/src/runtime/rt0_linux_ppc64le.s +++ b/src/runtime/rt0_linux_ppc64le.s @@ -12,7 +12,7 @@ TEXT _rt0_ppc64le_linux_lib(SB),NOSPLIT,$-8 MOVW CR, R0 // Save CR in caller's frame MOVD R0, 8(R1) MOVDU R1, -320(R1) // Allocate frame. - + // Preserve callee-save registers. MOVD R14, 24(R1) MOVD R15, 32(R1) diff --git a/src/runtime/rt0_nacl_amd64p32.s b/src/runtime/rt0_nacl_amd64p32.s index 54e4b1de89..38583c58b2 100644 --- a/src/runtime/rt0_nacl_amd64p32.s +++ b/src/runtime/rt0_nacl_amd64p32.s @@ -11,7 +11,7 @@ // 8(DI) - argc // 12(DI) - argv, then 0, then envv, then 0, then auxv // NaCl entry here is almost the same, except that there -// is no saved caller PC, so 0(FP) is -8(FP) and so on. +// is no saved caller PC, so 0(FP) is -8(FP) and so on. TEXT _rt0_amd64p32_nacl(SB),NOSPLIT,$16 MOVL DI, 0(SP) CALL runtime·nacl_sysinfo(SB) diff --git a/src/runtime/rt0_windows_arm.s b/src/runtime/rt0_windows_arm.s new file mode 100644 index 0000000000..c5787d0dee --- /dev/null +++ b/src/runtime/rt0_windows_arm.s @@ -0,0 +1,12 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go_asm.h" +#include "go_tls.h" +#include "textflag.h" + +// This is the entry point for the program from the +// kernel for an ordinary -buildmode=exe program. +TEXT _rt0_arm_windows(SB),NOSPLIT|NOFRAME,$0 + B ·rt0_go(SB) diff --git a/src/runtime/runtime-gdb_test.go b/src/runtime/runtime-gdb_test.go index d9c6f6d22a..0c24d3dce6 100644 --- a/src/runtime/runtime-gdb_test.go +++ b/src/runtime/runtime-gdb_test.go @@ -242,14 +242,14 @@ func testGdbPython(t *testing.T, cgo bool) { t.Fatalf("info goroutines failed: %s", bl) } - printMapvarRe1 := regexp.MustCompile(`\Q = map[string]string = {["abc"] = "def", ["ghi"] = "jkl"}\E$`) - printMapvarRe2 := regexp.MustCompile(`\Q = map[string]string = {["ghi"] = "jkl", ["abc"] = "def"}\E$`) + printMapvarRe1 := regexp.MustCompile(`^\$[0-9]+ = map\[string\]string = {\[(0x[0-9a-f]+\s+)?"abc"\] = (0x[0-9a-f]+\s+)?"def", \[(0x[0-9a-f]+\s+)?"ghi"\] = (0x[0-9a-f]+\s+)?"jkl"}$`) + printMapvarRe2 := regexp.MustCompile(`^\$[0-9]+ = map\[string\]string = {\[(0x[0-9a-f]+\s+)?"ghi"\] = (0x[0-9a-f]+\s+)?"jkl", \[(0x[0-9a-f]+\s+)?"abc"\] = (0x[0-9a-f]+\s+)?"def"}$`) if bl := blocks["print mapvar"]; !printMapvarRe1.MatchString(bl) && !printMapvarRe2.MatchString(bl) { t.Fatalf("print mapvar failed: %s", bl) } - strVarRe := regexp.MustCompile(`\Q = "abc"\E$`) + strVarRe := regexp.MustCompile(`^\$[0-9]+ = (0x[0-9a-f]+\s+)?"abc"$`) if bl := blocks["print strvar"]; !strVarRe.MatchString(bl) { t.Fatalf("print strvar failed: %s", bl) } @@ -263,8 +263,11 @@ func testGdbPython(t *testing.T, cgo bool) { // aggregates from their fields and reverted their printing // back to its original form. - infoLocalsRe := regexp.MustCompile(`slicevar *= *\[\]string *= *{"def"}`) - if bl := blocks["info locals"]; !infoLocalsRe.MatchString(bl) { + infoLocalsRe1 := regexp.MustCompile(`slicevar *= *\[\]string *= *{"def"}`) + // Format output from gdb v8.2 + infoLocalsRe2 := regexp.MustCompile(`^slicevar = .*\nmapvar = .*\nstrvar = 0x[0-9a-f]+ "abc"`) + if bl := blocks["info locals"]; !infoLocalsRe1.MatchString(bl) && + !infoLocalsRe2.MatchString(bl) { t.Fatalf("info locals failed: %s", bl) } @@ -425,11 +428,11 @@ func TestGdbAutotmpTypes(t *testing.T) { // Check that the backtrace matches the source code. types := []string{ - "struct []main.astruct;", - "struct bucket<string,main.astruct>;", - "struct hash<string,main.astruct>;", - "struct main.astruct;", - "typedef struct hash<string,main.astruct> * map[string]main.astruct;", + "[]main.astruct;", + "bucket<string,main.astruct>;", + "hash<string,main.astruct>;", + "main.astruct;", + "hash<string,main.astruct> * map[string]main.astruct;", } for _, name := range types { if !strings.Contains(sgot, name) { @@ -484,13 +487,13 @@ func TestGdbConst(t *testing.T) { "-ex", "print main.aConstant", "-ex", "print main.largeConstant", "-ex", "print main.minusOne", - "-ex", "print 'runtime._MSpanInUse'", + "-ex", "print 'runtime.mSpanInUse'", "-ex", "print 'runtime._PageSize'", filepath.Join(dir, "a.exe"), } got, _ := exec.Command("gdb", args...).CombinedOutput() - sgot := strings.Replace(string(got), "\r\n", "\n", -1) + sgot := strings.ReplaceAll(string(got), "\r\n", "\n") t.Logf("output %q", sgot) diff --git a/src/runtime/runtime1.go b/src/runtime/runtime1.go index d5f78baded..8b8f4dcb1e 100644 --- a/src/runtime/runtime1.go +++ b/src/runtime/runtime1.go @@ -305,7 +305,6 @@ var debug struct { gccheckmark int32 gcpacertrace int32 gcshrinkstackoff int32 - gcrescanstacks int32 gcstoptheworld int32 gctrace int32 invalidptr int32 @@ -323,7 +322,6 @@ var dbgvars = []dbgVar{ {"gccheckmark", &debug.gccheckmark}, {"gcpacertrace", &debug.gcpacertrace}, {"gcshrinkstackoff", &debug.gcshrinkstackoff}, - {"gcrescanstacks", &debug.gcrescanstacks}, {"gcstoptheworld", &debug.gcstoptheworld}, {"gctrace", &debug.gctrace}, {"invalidptr", &debug.invalidptr}, @@ -416,7 +414,9 @@ func timediv(v int64, div int32, rem *int32) int32 { for bit := 30; bit >= 0; bit-- { if v >= int64(div)<<uint(bit) { v = v - (int64(div) << uint(bit)) - res += 1 << uint(bit) + // Before this for loop, res was 0, thus all these + // power of 2 increments are now just bitsets. + res |= 1 << uint(bit) } } if v >= int64(div) { diff --git a/src/runtime/runtime2.go b/src/runtime/runtime2.go index 259bb376ae..bbb66bb8fa 100644 --- a/src/runtime/runtime2.go +++ b/src/runtime/runtime2.go @@ -424,7 +424,6 @@ type m struct { locks int32 dying int32 profilehz int32 - helpgc int32 spinning bool // m is out of work and is actively looking for work blocked bool // m is blocked on a note inwb bool // m is executing a write barrier @@ -580,6 +579,18 @@ type schedt struct { runq gQueue runqsize int32 + // disable controls selective disabling of the scheduler. + // + // Use schedEnableUser to control this. + // + // disable is protected by sched.lock. + disable struct { + // user disables scheduling of user goroutines. + user bool + runnable gQueue // pending runnable Gs + n int32 // length of runnable + } + // Global cache of dead G's. gFree struct { lock mutex @@ -639,14 +650,16 @@ type _func struct { entry uintptr // start pc nameoff int32 // function name - args int32 // in/out args size - funcID funcID // set for certain special runtime functions + args int32 // in/out args size + deferreturn uint32 // offset of a deferreturn block from entry, if any. pcsp int32 pcfile int32 pcln int32 npcdata int32 - nfuncdata int32 + funcID funcID // set for certain special runtime functions + _ [2]int8 // unused + nfuncdata uint8 // must be last } // layout of Itab known to compilers diff --git a/src/runtime/runtime_unix_test.go b/src/runtime/runtime_unix_test.go index e91216365e..b0cbbbe3e6 100644 --- a/src/runtime/runtime_unix_test.go +++ b/src/runtime/runtime_unix_test.go @@ -6,7 +6,7 @@ // We need a fast system call to provoke the race, // and Close(-1) is nearly universally fast. -// +build darwin dragonfly freebsd linux netbsd openbsd plan9 +// +build aix darwin dragonfly freebsd linux netbsd openbsd plan9 package runtime_test diff --git a/src/runtime/select.go b/src/runtime/select.go index 3a3ac6b7ac..2729c2ecf9 100644 --- a/src/runtime/select.go +++ b/src/runtime/select.go @@ -245,7 +245,7 @@ loop: case caseSend: if raceenabled { - racereadpc(unsafe.Pointer(c), cas.pc, chansendpc) + racereadpc(c.raceaddr(), cas.pc, chansendpc) } if c.closed != 0 { goto sclose @@ -462,7 +462,7 @@ rclose: typedmemclr(c.elemtype, cas.elem) } if raceenabled { - raceacquire(unsafe.Pointer(c)) + raceacquire(c.raceaddr()) } goto retc diff --git a/src/runtime/semasleep_test.go b/src/runtime/semasleep_test.go new file mode 100644 index 0000000000..5b2cc64483 --- /dev/null +++ b/src/runtime/semasleep_test.go @@ -0,0 +1,88 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +//+build !nacl,!plan9,!windows,!js + +package runtime_test + +import ( + "internal/testenv" + "io/ioutil" + "os" + "os/exec" + "path/filepath" + "syscall" + "testing" + "time" +) + +// Issue #27250. Spurious wakeups to pthread_cond_timedwait_relative_np +// shouldn't cause semasleep to retry with the same timeout which would +// cause indefinite spinning. +func TestSpuriousWakeupsNeverHangSemasleep(t *testing.T) { + testenv.MustHaveGoBuild(t) + tempDir, err := ioutil.TempDir("", "issue-27250") + if err != nil { + t.Fatalf("Failed to create the temp directory: %v", err) + } + defer os.RemoveAll(tempDir) + + repro := ` + package main + + import "time" + + func main() { + <-time.After(1 * time.Second) + } + ` + mainPath := filepath.Join(tempDir, "main.go") + if err := ioutil.WriteFile(mainPath, []byte(repro), 0644); err != nil { + t.Fatalf("Failed to create temp file for repro.go: %v", err) + } + binaryPath := filepath.Join(tempDir, "binary") + + // Build the binary so that we can send the signal to its PID. + out, err := exec.Command(testenv.GoToolPath(t), "build", "-o", binaryPath, mainPath).CombinedOutput() + if err != nil { + t.Fatalf("Failed to compile the binary: err: %v\nOutput: %s\n", err, out) + } + if err := os.Chmod(binaryPath, 0755); err != nil { + t.Fatalf("Failed to chmod binary: %v", err) + } + + // Now run the binary. + cmd := exec.Command(binaryPath) + if err := cmd.Start(); err != nil { + t.Fatalf("Failed to start command: %v", err) + } + doneCh := make(chan error, 1) + go func() { + doneCh <- cmd.Wait() + }() + + // With the repro running, we can continuously send to it + // a non-terminal signal such as SIGIO, to spuriously + // wakeup pthread_cond_timedwait_relative_np. + unfixedTimer := time.NewTimer(2 * time.Second) + for { + select { + case <-time.After(200 * time.Millisecond): + // Send the pesky signal that toggles spinning + // indefinitely if #27520 is not fixed. + cmd.Process.Signal(syscall.SIGIO) + + case <-unfixedTimer.C: + t.Error("Program failed to return on time and has to be killed, issue #27520 still exists") + cmd.Process.Signal(syscall.SIGKILL) + return + + case err := <-doneCh: + if err != nil { + t.Fatalf("The program returned but unfortunately with an error: %v", err) + } + return + } + } +} diff --git a/src/runtime/signal_aix_ppc64.go b/src/runtime/signal_aix_ppc64.go new file mode 100644 index 0000000000..c17563e2a5 --- /dev/null +++ b/src/runtime/signal_aix_ppc64.go @@ -0,0 +1,85 @@ +/// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build aix + +package runtime + +import ( + "runtime/internal/sys" + "unsafe" +) + +type sigctxt struct { + info *siginfo + ctxt unsafe.Pointer +} + +//go:nosplit +//go:nowritebarrierrec +func (c *sigctxt) regs() *context64 { return &(*ucontext)(c.ctxt).uc_mcontext } + +func (c *sigctxt) r0() uint64 { return c.regs().gpr[0] } +func (c *sigctxt) r1() uint64 { return c.regs().gpr[1] } +func (c *sigctxt) r2() uint64 { return c.regs().gpr[2] } +func (c *sigctxt) r3() uint64 { return c.regs().gpr[3] } +func (c *sigctxt) r4() uint64 { return c.regs().gpr[4] } +func (c *sigctxt) r5() uint64 { return c.regs().gpr[5] } +func (c *sigctxt) r6() uint64 { return c.regs().gpr[6] } +func (c *sigctxt) r7() uint64 { return c.regs().gpr[7] } +func (c *sigctxt) r8() uint64 { return c.regs().gpr[8] } +func (c *sigctxt) r9() uint64 { return c.regs().gpr[9] } +func (c *sigctxt) r10() uint64 { return c.regs().gpr[10] } +func (c *sigctxt) r11() uint64 { return c.regs().gpr[11] } +func (c *sigctxt) r12() uint64 { return c.regs().gpr[12] } +func (c *sigctxt) r13() uint64 { return c.regs().gpr[13] } +func (c *sigctxt) r14() uint64 { return c.regs().gpr[14] } +func (c *sigctxt) r15() uint64 { return c.regs().gpr[15] } +func (c *sigctxt) r16() uint64 { return c.regs().gpr[16] } +func (c *sigctxt) r17() uint64 { return c.regs().gpr[17] } +func (c *sigctxt) r18() uint64 { return c.regs().gpr[18] } +func (c *sigctxt) r19() uint64 { return c.regs().gpr[19] } +func (c *sigctxt) r20() uint64 { return c.regs().gpr[20] } +func (c *sigctxt) r21() uint64 { return c.regs().gpr[21] } +func (c *sigctxt) r22() uint64 { return c.regs().gpr[22] } +func (c *sigctxt) r23() uint64 { return c.regs().gpr[23] } +func (c *sigctxt) r24() uint64 { return c.regs().gpr[24] } +func (c *sigctxt) r25() uint64 { return c.regs().gpr[25] } +func (c *sigctxt) r26() uint64 { return c.regs().gpr[26] } +func (c *sigctxt) r27() uint64 { return c.regs().gpr[27] } +func (c *sigctxt) r28() uint64 { return c.regs().gpr[28] } +func (c *sigctxt) r29() uint64 { return c.regs().gpr[29] } +func (c *sigctxt) r30() uint64 { return c.regs().gpr[30] } +func (c *sigctxt) r31() uint64 { return c.regs().gpr[31] } +func (c *sigctxt) sp() uint64 { return c.regs().gpr[1] } + +//go:nosplit +//go:nowritebarrierrec +func (c *sigctxt) pc() uint64 { return c.regs().iar } + +func (c *sigctxt) ctr() uint64 { return c.regs().ctr } +func (c *sigctxt) link() uint64 { return c.regs().lr } +func (c *sigctxt) xer() uint32 { return c.regs().xer } +func (c *sigctxt) ccr() uint32 { return c.regs().cr } +func (c *sigctxt) fpscr() uint32 { return c.regs().fpscr } +func (c *sigctxt) fpscrx() uint32 { return c.regs().fpscrx } + +// TODO(aix): find trap equivalent +func (c *sigctxt) trap() uint32 { return 0x0 } + +func (c *sigctxt) sigcode() uint32 { return uint32(c.info.si_code) } +func (c *sigctxt) sigaddr() uint64 { return uint64(c.info.si_addr) } +func (c *sigctxt) fault() uintptr { return uintptr(c.sigaddr()) } + +func (c *sigctxt) set_r0(x uint64) { c.regs().gpr[0] = x } +func (c *sigctxt) set_r12(x uint64) { c.regs().gpr[12] = x } +func (c *sigctxt) set_r30(x uint64) { c.regs().gpr[30] = x } +func (c *sigctxt) set_pc(x uint64) { c.regs().iar = x } +func (c *sigctxt) set_sp(x uint64) { c.regs().gpr[1] = x } +func (c *sigctxt) set_link(x uint64) { c.regs().lr = x } + +func (c *sigctxt) set_sigcode(x uint32) { c.info.si_code = int32(x) } +func (c *sigctxt) set_sigaddr(x uint64) { + *(*uintptr)(add(unsafe.Pointer(c.info), 2*sys.PtrSize)) = uintptr(x) +} diff --git a/src/runtime/signal_ppc64x.go b/src/runtime/signal_ppc64x.go index 5a1a5cae60..cac1a23c9f 100644 --- a/src/runtime/signal_ppc64x.go +++ b/src/runtime/signal_ppc64x.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build linux +// +build aix linux // +build ppc64 ppc64le package runtime diff --git a/src/runtime/signal_sighandler.go b/src/runtime/signal_sighandler.go index 5a734f9050..6e71e41f52 100644 --- a/src/runtime/signal_sighandler.go +++ b/src/runtime/signal_sighandler.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris +// +build aix darwin dragonfly freebsd linux nacl netbsd openbsd solaris package runtime diff --git a/src/runtime/signal_unix.go b/src/runtime/signal_unix.go index 6cd9f8ddb6..12a938c8c9 100644 --- a/src/runtime/signal_unix.go +++ b/src/runtime/signal_unix.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build darwin dragonfly freebsd linux netbsd openbsd solaris +// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris package runtime diff --git a/src/runtime/signal_windows.go b/src/runtime/signal_windows.go index a63450038d..873ce66abe 100644 --- a/src/runtime/signal_windows.go +++ b/src/runtime/signal_windows.go @@ -27,7 +27,7 @@ func lastcontinuetramp() func initExceptionHandler() { stdcall2(_AddVectoredExceptionHandler, 1, funcPC(exceptiontramp)) - if _AddVectoredContinueHandler == nil || unsafe.Sizeof(&_AddVectoredContinueHandler) == 4 { + if _AddVectoredContinueHandler == nil || GOARCH == "386" { // use SetUnhandledExceptionFilter for windows-386 or // if VectoredContinueHandler is unavailable. // note: SetUnhandledExceptionFilter handler won't be called, if debugging. @@ -177,9 +177,15 @@ func lastcontinuehandler(info *exceptionrecord, r *context, gp *g) int32 { } print("\n") + // TODO(jordanrh1): This may be needed for 386/AMD64 as well. + if GOARCH == "arm" { + _g_.m.throwing = 1 + _g_.m.caughtsig.set(gp) + } + level, _, docrash := gotraceback() if level > 0 { - tracebacktrap(r.ip(), r.sp(), 0, gp) + tracebacktrap(r.ip(), r.sp(), r.lr(), gp) tracebackothers(gp) dumpregs(r) } diff --git a/src/runtime/sigtab_aix.go b/src/runtime/sigtab_aix.go new file mode 100644 index 0000000000..42e5606ab6 --- /dev/null +++ b/src/runtime/sigtab_aix.go @@ -0,0 +1,264 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package runtime + +var sigtable = [...]sigTabT{ + 0: {0, "SIGNONE: no trap"}, + _SIGHUP: {_SigNotify + _SigKill, "SIGHUP: terminal line hangup"}, + _SIGINT: {_SigNotify + _SigKill, "SIGINT: interrupt"}, + _SIGQUIT: {_SigNotify + _SigThrow, "SIGQUIT: quit"}, + _SIGILL: {_SigThrow + _SigUnblock, "SIGILL: illegal instruction"}, + _SIGTRAP: {_SigThrow + _SigUnblock, "SIGTRAP: trace trap"}, + _SIGABRT: {_SigNotify + _SigThrow, "SIGABRT: abort"}, + _SIGBUS: {_SigPanic + _SigUnblock, "SIGBUS: bus error"}, + _SIGFPE: {_SigPanic + _SigUnblock, "SIGFPE: floating-point exception"}, + _SIGKILL: {0, "SIGKILL: kill"}, + _SIGUSR1: {_SigNotify, "SIGUSR1: user-defined signal 1"}, + _SIGSEGV: {_SigPanic + _SigUnblock, "SIGSEGV: segmentation violation"}, + _SIGUSR2: {_SigNotify, "SIGUSR2: user-defined signal 2"}, + _SIGPIPE: {_SigNotify, "SIGPIPE: write to broken pipe"}, + _SIGALRM: {_SigNotify, "SIGALRM: alarm clock"}, + _SIGTERM: {_SigNotify + _SigKill, "SIGTERM: termination"}, + _SIGCHLD: {_SigNotify + _SigUnblock, "SIGCHLD: child status has changed"}, + _SIGCONT: {_SigNotify + _SigDefault, "SIGCONT: continue"}, + _SIGSTOP: {0, "SIGSTOP: stop"}, + _SIGTSTP: {_SigNotify + _SigDefault, "SIGTSTP: keyboard stop"}, + _SIGTTIN: {_SigNotify + _SigDefault, "SIGTTIN: background read from tty"}, + _SIGTTOU: {_SigNotify + _SigDefault, "SIGTTOU: background write to tty"}, + _SIGURG: {_SigNotify, "SIGURG: urgent condition on socket"}, + _SIGXCPU: {_SigNotify, "SIGXCPU: cpu limit exceeded"}, + _SIGXFSZ: {_SigNotify, "SIGXFSZ: file size limit exceeded"}, + _SIGVTALRM: {_SigNotify, "SIGVTALRM: virtual alarm clock"}, + _SIGPROF: {_SigNotify + _SigUnblock, "SIGPROF: profiling alarm clock"}, + _SIGWINCH: {_SigNotify, "SIGWINCH: window size change"}, + _SIGSYS: {_SigThrow, "SIGSYS: bad system call"}, + _SIGIO: {_SigNotify, "SIGIO: i/o now possible"}, + _SIGPWR: {_SigNotify, "SIGPWR: power failure restart"}, + _SIGEMT: {_SigThrow, "SIGEMT: emulate instruction executed"}, + _SIGWAITING: {0, "SIGWAITING: reserved signal no longer used by"}, + 26: {_SigNotify, "signal 26"}, + 27: {_SigNotify, "signal 27"}, + 33: {_SigNotify, "signal 33"}, + 35: {_SigNotify, "signal 35"}, + 36: {_SigNotify, "signal 36"}, + 37: {_SigNotify, "signal 37"}, + 38: {_SigNotify, "signal 38"}, + 40: {_SigNotify, "signal 40"}, + 41: {_SigNotify, "signal 41"}, + 42: {_SigNotify, "signal 42"}, + 43: {_SigNotify, "signal 43"}, + 44: {_SigNotify, "signal 44"}, + 45: {_SigNotify, "signal 45"}, + 46: {_SigNotify, "signal 46"}, + 47: {_SigNotify, "signal 47"}, + 48: {_SigNotify, "signal 48"}, + 49: {_SigNotify, "signal 49"}, + 50: {_SigNotify, "signal 50"}, + 51: {_SigNotify, "signal 51"}, + 52: {_SigNotify, "signal 52"}, + 53: {_SigNotify, "signal 53"}, + 54: {_SigNotify, "signal 54"}, + 55: {_SigNotify, "signal 55"}, + 56: {_SigNotify, "signal 56"}, + 57: {_SigNotify, "signal 57"}, + 58: {_SigNotify, "signal 58"}, + 59: {_SigNotify, "signal 59"}, + 60: {_SigNotify, "signal 60"}, + 61: {_SigNotify, "signal 61"}, + 62: {_SigNotify, "signal 62"}, + 63: {_SigNotify, "signal 63"}, + 64: {_SigNotify, "signal 64"}, + 65: {_SigNotify, "signal 65"}, + 66: {_SigNotify, "signal 66"}, + 67: {_SigNotify, "signal 67"}, + 68: {_SigNotify, "signal 68"}, + 69: {_SigNotify, "signal 69"}, + 70: {_SigNotify, "signal 70"}, + 71: {_SigNotify, "signal 71"}, + 72: {_SigNotify, "signal 72"}, + 73: {_SigNotify, "signal 73"}, + 74: {_SigNotify, "signal 74"}, + 75: {_SigNotify, "signal 75"}, + 76: {_SigNotify, "signal 76"}, + 77: {_SigNotify, "signal 77"}, + 78: {_SigNotify, "signal 78"}, + 79: {_SigNotify, "signal 79"}, + 80: {_SigNotify, "signal 80"}, + 81: {_SigNotify, "signal 81"}, + 82: {_SigNotify, "signal 82"}, + 83: {_SigNotify, "signal 83"}, + 84: {_SigNotify, "signal 84"}, + 85: {_SigNotify, "signal 85"}, + 86: {_SigNotify, "signal 86"}, + 87: {_SigNotify, "signal 87"}, + 88: {_SigNotify, "signal 88"}, + 89: {_SigNotify, "signal 89"}, + 90: {_SigNotify, "signal 90"}, + 91: {_SigNotify, "signal 91"}, + 92: {_SigNotify, "signal 92"}, + 93: {_SigNotify, "signal 93"}, + 94: {_SigNotify, "signal 94"}, + 95: {_SigNotify, "signal 95"}, + 96: {_SigNotify, "signal 96"}, + 97: {_SigNotify, "signal 97"}, + 98: {_SigNotify, "signal 98"}, + 99: {_SigNotify, "signal 99"}, + 100: {_SigNotify, "signal 100"}, + 101: {_SigNotify, "signal 101"}, + 102: {_SigNotify, "signal 102"}, + 103: {_SigNotify, "signal 103"}, + 104: {_SigNotify, "signal 104"}, + 105: {_SigNotify, "signal 105"}, + 106: {_SigNotify, "signal 106"}, + 107: {_SigNotify, "signal 107"}, + 108: {_SigNotify, "signal 108"}, + 109: {_SigNotify, "signal 109"}, + 110: {_SigNotify, "signal 110"}, + 111: {_SigNotify, "signal 111"}, + 112: {_SigNotify, "signal 112"}, + 113: {_SigNotify, "signal 113"}, + 114: {_SigNotify, "signal 114"}, + 115: {_SigNotify, "signal 115"}, + 116: {_SigNotify, "signal 116"}, + 117: {_SigNotify, "signal 117"}, + 118: {_SigNotify, "signal 118"}, + 119: {_SigNotify, "signal 119"}, + 120: {_SigNotify, "signal 120"}, + 121: {_SigNotify, "signal 121"}, + 122: {_SigNotify, "signal 122"}, + 123: {_SigNotify, "signal 123"}, + 124: {_SigNotify, "signal 124"}, + 125: {_SigNotify, "signal 125"}, + 126: {_SigNotify, "signal 126"}, + 127: {_SigNotify, "signal 127"}, + 128: {_SigNotify, "signal 128"}, + 129: {_SigNotify, "signal 129"}, + 130: {_SigNotify, "signal 130"}, + 131: {_SigNotify, "signal 131"}, + 132: {_SigNotify, "signal 132"}, + 133: {_SigNotify, "signal 133"}, + 134: {_SigNotify, "signal 134"}, + 135: {_SigNotify, "signal 135"}, + 136: {_SigNotify, "signal 136"}, + 137: {_SigNotify, "signal 137"}, + 138: {_SigNotify, "signal 138"}, + 139: {_SigNotify, "signal 139"}, + 140: {_SigNotify, "signal 140"}, + 141: {_SigNotify, "signal 141"}, + 142: {_SigNotify, "signal 142"}, + 143: {_SigNotify, "signal 143"}, + 144: {_SigNotify, "signal 144"}, + 145: {_SigNotify, "signal 145"}, + 146: {_SigNotify, "signal 146"}, + 147: {_SigNotify, "signal 147"}, + 148: {_SigNotify, "signal 148"}, + 149: {_SigNotify, "signal 149"}, + 150: {_SigNotify, "signal 150"}, + 151: {_SigNotify, "signal 151"}, + 152: {_SigNotify, "signal 152"}, + 153: {_SigNotify, "signal 153"}, + 154: {_SigNotify, "signal 154"}, + 155: {_SigNotify, "signal 155"}, + 156: {_SigNotify, "signal 156"}, + 157: {_SigNotify, "signal 157"}, + 158: {_SigNotify, "signal 158"}, + 159: {_SigNotify, "signal 159"}, + 160: {_SigNotify, "signal 160"}, + 161: {_SigNotify, "signal 161"}, + 162: {_SigNotify, "signal 162"}, + 163: {_SigNotify, "signal 163"}, + 164: {_SigNotify, "signal 164"}, + 165: {_SigNotify, "signal 165"}, + 166: {_SigNotify, "signal 166"}, + 167: {_SigNotify, "signal 167"}, + 168: {_SigNotify, "signal 168"}, + 169: {_SigNotify, "signal 169"}, + 170: {_SigNotify, "signal 170"}, + 171: {_SigNotify, "signal 171"}, + 172: {_SigNotify, "signal 172"}, + 173: {_SigNotify, "signal 173"}, + 174: {_SigNotify, "signal 174"}, + 175: {_SigNotify, "signal 175"}, + 176: {_SigNotify, "signal 176"}, + 177: {_SigNotify, "signal 177"}, + 178: {_SigNotify, "signal 178"}, + 179: {_SigNotify, "signal 179"}, + 180: {_SigNotify, "signal 180"}, + 181: {_SigNotify, "signal 181"}, + 182: {_SigNotify, "signal 182"}, + 183: {_SigNotify, "signal 183"}, + 184: {_SigNotify, "signal 184"}, + 185: {_SigNotify, "signal 185"}, + 186: {_SigNotify, "signal 186"}, + 187: {_SigNotify, "signal 187"}, + 188: {_SigNotify, "signal 188"}, + 189: {_SigNotify, "signal 189"}, + 190: {_SigNotify, "signal 190"}, + 191: {_SigNotify, "signal 191"}, + 192: {_SigNotify, "signal 192"}, + 193: {_SigNotify, "signal 193"}, + 194: {_SigNotify, "signal 194"}, + 195: {_SigNotify, "signal 195"}, + 196: {_SigNotify, "signal 196"}, + 197: {_SigNotify, "signal 197"}, + 198: {_SigNotify, "signal 198"}, + 199: {_SigNotify, "signal 199"}, + 200: {_SigNotify, "signal 200"}, + 201: {_SigNotify, "signal 201"}, + 202: {_SigNotify, "signal 202"}, + 203: {_SigNotify, "signal 203"}, + 204: {_SigNotify, "signal 204"}, + 205: {_SigNotify, "signal 205"}, + 206: {_SigNotify, "signal 206"}, + 207: {_SigNotify, "signal 207"}, + 208: {_SigNotify, "signal 208"}, + 209: {_SigNotify, "signal 209"}, + 210: {_SigNotify, "signal 210"}, + 211: {_SigNotify, "signal 211"}, + 212: {_SigNotify, "signal 212"}, + 213: {_SigNotify, "signal 213"}, + 214: {_SigNotify, "signal 214"}, + 215: {_SigNotify, "signal 215"}, + 216: {_SigNotify, "signal 216"}, + 217: {_SigNotify, "signal 217"}, + 218: {_SigNotify, "signal 218"}, + 219: {_SigNotify, "signal 219"}, + 220: {_SigNotify, "signal 220"}, + 221: {_SigNotify, "signal 221"}, + 222: {_SigNotify, "signal 222"}, + 223: {_SigNotify, "signal 223"}, + 224: {_SigNotify, "signal 224"}, + 225: {_SigNotify, "signal 225"}, + 226: {_SigNotify, "signal 226"}, + 227: {_SigNotify, "signal 227"}, + 228: {_SigNotify, "signal 228"}, + 229: {_SigNotify, "signal 229"}, + 230: {_SigNotify, "signal 230"}, + 231: {_SigNotify, "signal 231"}, + 232: {_SigNotify, "signal 232"}, + 233: {_SigNotify, "signal 233"}, + 234: {_SigNotify, "signal 234"}, + 235: {_SigNotify, "signal 235"}, + 236: {_SigNotify, "signal 236"}, + 237: {_SigNotify, "signal 237"}, + 238: {_SigNotify, "signal 238"}, + 239: {_SigNotify, "signal 239"}, + 240: {_SigNotify, "signal 240"}, + 241: {_SigNotify, "signal 241"}, + 242: {_SigNotify, "signal 242"}, + 243: {_SigNotify, "signal 243"}, + 244: {_SigNotify, "signal 244"}, + 245: {_SigNotify, "signal 245"}, + 246: {_SigNotify, "signal 246"}, + 247: {_SigNotify, "signal 247"}, + 248: {_SigNotify, "signal 248"}, + 249: {_SigNotify, "signal 249"}, + 250: {_SigNotify, "signal 250"}, + 251: {_SigNotify, "signal 251"}, + 252: {_SigNotify, "signal 252"}, + 253: {_SigNotify, "signal 253"}, + 254: {_SigNotify, "signal 254"}, + 255: {_SigNotify, "signal 255"}, +} diff --git a/src/runtime/stack.go b/src/runtime/stack.go index c7bfc0434b..b815aa859e 100644 --- a/src/runtime/stack.go +++ b/src/runtime/stack.go @@ -211,7 +211,7 @@ func stackpoolalloc(order uint8) gclinkptr { // Adds stack x to the free pool. Must be called with stackpoolmu held. func stackpoolfree(x gclinkptr, order uint8) { s := spanOfUnchecked(uintptr(x)) - if s.state != _MSpanManual { + if s.state != mSpanManual { throw("freeing stack not in a stack span") } if s.manualFreeList.ptr() == nil { @@ -350,7 +350,7 @@ func stackalloc(n uint32) stack { } var x gclinkptr c := thisg.m.mcache - if stackNoCache != 0 || c == nil || thisg.m.preemptoff != "" || thisg.m.helpgc != 0 { + if stackNoCache != 0 || c == nil || thisg.m.preemptoff != "" { // c == nil can happen in the guts of exitsyscall or // procresize. Just get a stack from the global pool. // Also don't touch stackcache during gc @@ -445,7 +445,7 @@ func stackfree(stk stack) { } x := gclinkptr(v) c := gp.m.mcache - if stackNoCache != 0 || c == nil || gp.m.preemptoff != "" || gp.m.helpgc != 0 { + if stackNoCache != 0 || c == nil || gp.m.preemptoff != "" { lock(&stackpoolmu) stackpoolfree(x, order) unlock(&stackpoolmu) @@ -459,7 +459,7 @@ func stackfree(stk stack) { } } else { s := spanOfUnchecked(uintptr(v)) - if s.state != _MSpanManual { + if s.state != mSpanManual { println(hex(s.base()), v) throw("bad span state") } @@ -625,7 +625,7 @@ func adjustframe(frame *stkframe, arg unsafe.Pointer) bool { return true } - locals, args := getStackMap(frame, &adjinfo.cache, true) + locals, args, objs := getStackMap(frame, &adjinfo.cache, true) // Adjust local variables if stack frame has been allocated. if locals.n > 0 { @@ -663,6 +663,42 @@ func adjustframe(frame *stkframe, arg unsafe.Pointer) bool { } adjustpointers(unsafe.Pointer(frame.argp), &args, adjinfo, funcInfo{}) } + + // Adjust pointers in all stack objects (whether they are live or not). + // See comments in mgcmark.go:scanframeworker. + if frame.varp != 0 { + for _, obj := range objs { + off := obj.off + base := frame.varp // locals base pointer + if off >= 0 { + base = frame.argp // arguments and return values base pointer + } + p := base + uintptr(off) + if p < frame.sp { + // Object hasn't been allocated in the frame yet. + // (Happens when the stack bounds check fails and + // we call into morestack.) + continue + } + t := obj.typ + gcdata := t.gcdata + var s *mspan + if t.kind&kindGCProg != 0 { + // See comments in mgcmark.go:scanstack + s = materializeGCProg(t.ptrdata, gcdata) + gcdata = (*byte)(unsafe.Pointer(s.startAddr)) + } + for i := uintptr(0); i < t.ptrdata; i += sys.PtrSize { + if *addb(gcdata, i/(8*sys.PtrSize))>>(i/sys.PtrSize&7)&1 != 0 { + adjustpointer(adjinfo, unsafe.Pointer(p+i)) + } + } + if s != nil { + dematerializeGCProg(s) + } + } + } + return true } @@ -981,9 +1017,6 @@ func newstack() { // system stack. gcw := &gp.m.p.ptr().gcw scanstack(gp, gcw) - if gcBlackenPromptly { - gcw.dispose() - } gp.gcscandone = true } gp.preemptscan = false @@ -1139,9 +1172,9 @@ func freeStackSpans() { unlock(&stackLarge.lock) } -// getStackMap returns the locals and arguments live pointer maps for -// frame. -func getStackMap(frame *stkframe, cache *pcvalueCache, debug bool) (locals, args bitvector) { +// getStackMap returns the locals and arguments live pointer maps, and +// stack object list for frame. +func getStackMap(frame *stkframe, cache *pcvalueCache, debug bool) (locals, args bitvector, objs []stackObjectRecord) { targetpc := frame.continpc if targetpc == 0 { // Frame is dead. Return empty bitvectors. @@ -1238,9 +1271,33 @@ func getStackMap(frame *stkframe, cache *pcvalueCache, debug bool) (locals, args } } } + + // stack objects. + p := funcdata(f, _FUNCDATA_StackObjects) + if p != nil { + n := *(*uintptr)(p) + p = add(p, sys.PtrSize) + *(*slice)(unsafe.Pointer(&objs)) = slice{array: noescape(p), len: int(n), cap: int(n)} + // Note: the noescape above is needed to keep + // getStackMap from from "leaking param content: + // frame". That leak propagates up to getgcmask, then + // GCMask, then verifyGCInfo, which converts the stack + // gcinfo tests into heap gcinfo tests :( + } + return } +// A stackObjectRecord is generated by the compiler for each stack object in a stack frame. +// This record must match the generator code in cmd/compile/internal/gc/ssa.go:emitStackObjects. +type stackObjectRecord struct { + // offset in frame + // if negative, offset from varp + // if non-negative, offset from argp + off int + typ *_type +} + //go:nosplit func morestackc() { throw("attempt to execute system stack code on user stack") diff --git a/src/runtime/stubs2.go b/src/runtime/stubs2.go index 02249d0aad..57134f7354 100644 --- a/src/runtime/stubs2.go +++ b/src/runtime/stubs2.go @@ -8,6 +8,7 @@ // +build !nacl // +build !js // +build !darwin +// +build !aix package runtime @@ -25,7 +26,8 @@ func write(fd uintptr, p unsafe.Pointer, n int32) int32 //go:noescape func open(name *byte, mode, perm int32) int32 -func madvise(addr unsafe.Pointer, n uintptr, flags int32) +// return value is only set on linux to be used in osinit() +func madvise(addr unsafe.Pointer, n uintptr, flags int32) int32 // exitThread terminates the current thread, writing *wait = 0 when // the stack is safe to reclaim. diff --git a/src/runtime/stubs3.go b/src/runtime/stubs3.go index 5c0786e411..a9ff689e79 100644 --- a/src/runtime/stubs3.go +++ b/src/runtime/stubs3.go @@ -8,6 +8,7 @@ // +build !nacl // +build !freebsd // +build !darwin +// +build !aix package runtime diff --git a/src/runtime/symtab.go b/src/runtime/symtab.go index d90ab86ffa..1dc7ab740e 100644 --- a/src/runtime/symtab.go +++ b/src/runtime/symtab.go @@ -348,6 +348,7 @@ const ( _FUNCDATA_LocalsPointerMaps = 1 _FUNCDATA_InlTree = 2 _FUNCDATA_RegPointerMaps = 3 + _FUNCDATA_StackObjects = 4 _ArgsSizeUnknown = -0x80000000 ) @@ -356,7 +357,7 @@ const ( // Note that in some situations involving plugins, there may be multiple // copies of a particular special runtime function. // Note: this list must match the list in cmd/internal/objabi/funcid.go. -type funcID uint32 +type funcID uint8 const ( funcID_normal funcID = iota // not a special function @@ -855,7 +856,7 @@ func pcdatavalue(f funcInfo, table int32, targetpc uintptr, cache *pcvalueCache) return pcvalue(f, off, targetpc, cache, true) } -func funcdata(f funcInfo, i int32) unsafe.Pointer { +func funcdata(f funcInfo, i uint8) unsafe.Pointer { if i < 0 || i >= f.nfuncdata { return nil } diff --git a/src/runtime/sys_aix_ppc64.s b/src/runtime/sys_aix_ppc64.s new file mode 100644 index 0000000000..38e60f99eb --- /dev/null +++ b/src/runtime/sys_aix_ppc64.s @@ -0,0 +1,201 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build aix +// +build ppc64 ppc64le + +// +// System calls and other sys.stuff for ppc64, Aix +// + +#include "go_asm.h" +#include "go_tls.h" +#include "textflag.h" +#include "asm_ppc64x.h" + +// This function calls a C function with the function descriptor in R12 +TEXT runtime·callCfunction(SB), NOSPLIT|NOFRAME,$0 + MOVD 0(R12), R12 + MOVD R2, 40(R1) + MOVD 0(R12), R0 + MOVD 8(R12), R2 + MOVD R0, CTR + BR (CTR) + + +// asmsyscall6 calls a library function with a function descriptor +// stored in libcall_fn and store the results in libcall struture +// Up to 6 arguments can be passed to this C function +// Called by runtime.asmcgocall +// It reserves a stack of 288 bytes for the C function. +// NOT USING GO CALLING CONVENTION +TEXT runtime·asmsyscall6(SB),NOSPLIT,$256 + MOVD R3, 48(R1) // Save libcall for later + MOVD libcall_fn(R3), R12 + MOVD libcall_args(R3), R9 + MOVD 0(R9), R3 + MOVD 8(R9), R4 + MOVD 16(R9), R5 + MOVD 24(R9), R6 + MOVD 32(R9), R7 + MOVD 40(R9), R8 + BL runtime·callCfunction(SB) + + // Restore R0 and TOC + XOR R0, R0 + MOVD 40(R1), R2 + + // Store result in libcall + MOVD 48(R1), R5 + MOVD R3, (libcall_r1)(R5) + MOVD $-1, R6 + CMP R6, R3 + BNE skiperrno + + // Save errno in libcall + BL runtime·load_g(SB) + MOVD g_m(g), R4 + MOVD (m_mOS + mOS_perrno)(R4), R9 + MOVW 0(R9), R9 + MOVD R9, (libcall_err)(R5) + RET +skiperrno: + // Reset errno if no error has been returned + MOVD R0, (libcall_err)(R5) + RET + + +TEXT runtime·sigfwd(SB),NOSPLIT,$0-32 + MOVW sig+8(FP), R3 + MOVD info+16(FP), R4 + MOVD ctx+24(FP), R5 + MOVD fn+0(FP), R12 + MOVD R12, CTR + BL (CTR) + RET + + +// runtime.sigtramp is a function descriptor to the real sigtramp. +DATA runtime·sigtramp+0(SB)/8, $runtime·_sigtramp(SB) +DATA runtime·sigtramp+8(SB)/8, $TOC(SB) +DATA runtime·sigtramp+16(SB)/8, $0 +GLOBL runtime·sigtramp(SB), NOPTR, $24 + +// This funcion must not have any frame as we want to control how +// every registers are used. +TEXT runtime·_sigtramp(SB),NOSPLIT|NOFRAME,$0 + MOVD LR, R0 + MOVD R0, 16(R1) + // initialize essential registers (just in case) + BL runtime·reginit(SB) + + // Note that we are executing on altsigstack here, so we have + // more stack available than NOSPLIT would have us believe. + // To defeat the linker, we make our own stack frame with + // more space. + SUB $128+FIXED_FRAME, R1 + + // Save registers + MOVD R31, 56(R1) + MOVD g, 64(R1) + MOVD R29, 72(R1) + + BL runtime·load_g(SB) + + // Save m->libcall. We need to do this because we + // might get interrupted by a signal in runtime·asmcgocall. + + // save m->libcall + MOVD g_m(g), R6 + MOVD (m_libcall+libcall_fn)(R6), R7 + MOVD R7, 80(R1) + MOVD (m_libcall+libcall_args)(R6), R7 + MOVD R7, 88(R1) + MOVD (m_libcall+libcall_n)(R6), R7 + MOVD R7, 96(R1) + MOVD (m_libcall+libcall_r1)(R6), R7 + MOVD R7, 104(R1) + MOVD (m_libcall+libcall_r2)(R6), R7 + MOVD R7, 112(R1) + + // save errno, it might be EINTR; stuff we do here might reset it. + MOVD (m_mOS+mOS_perrno)(R6), R8 + MOVD 0(R8), R8 + MOVD R8, 120(R1) + + MOVW R3, FIXED_FRAME+0(R1) + MOVD R4, FIXED_FRAME+8(R1) + MOVD R5, FIXED_FRAME+16(R1) + MOVD $runtime·sigtrampgo(SB), R12 + MOVD R12, CTR + BL (CTR) + + MOVD g_m(g), R6 + // restore libcall + MOVD 80(R1), R7 + MOVD R7, (m_libcall+libcall_fn)(R6) + MOVD 88(R1), R7 + MOVD R7, (m_libcall+libcall_args)(R6) + MOVD 96(R1), R7 + MOVD R7, (m_libcall+libcall_n)(R6) + MOVD 104(R1), R7 + MOVD R7, (m_libcall+libcall_r1)(R6) + MOVD 112(R1), R7 + MOVD R7, (m_libcall+libcall_r2)(R6) + + // restore errno + MOVD (m_mOS+mOS_perrno)(R6), R7 + MOVD 120(R1), R8 + MOVD R8, 0(R7) + + // restore registers + MOVD 56(R1),R31 + MOVD 64(R1),g + MOVD 72(R1),R29 + + // Don't use RET because we need to restore R31 ! + ADD $128+FIXED_FRAME, R1 + MOVD 16(R1), R0 + MOVD R0, LR + BR (LR) + +// runtime.tstart is a function descriptor to the real tstart. +DATA runtime·tstart+0(SB)/8, $runtime·_tstart(SB) +DATA runtime·tstart+8(SB)/8, $TOC(SB) +DATA runtime·tstart+16(SB)/8, $0 +GLOBL runtime·tstart(SB), NOPTR, $24 + +TEXT runtime·_tstart(SB),NOSPLIT,$0 + XOR R0, R0 // reset R0 + + // set g + MOVD m_g0(R3), g + BL runtime·save_g(SB) + MOVD R3, g_m(g) + + // Layout new m scheduler stack on os stack. + MOVD R1, R3 + MOVD R3, (g_stack+stack_hi)(g) + SUB $(const_threadStackSize), R3 // stack size + MOVD R3, (g_stack+stack_lo)(g) + ADD $const__StackGuard, R3 + MOVD R3, g_stackguard0(g) + MOVD R3, g_stackguard1(g) + + BL runtime·mstart(SB) + + MOVD R0, R3 + RET + +// Runs on OS stack, called from runtime·osyield. +TEXT runtime·osyield1(SB),NOSPLIT,$0 + MOVD $libc_sched_yield(SB), R12 + MOVD 0(R12), R12 + MOVD R2, 40(R1) + MOVD 0(R12), R0 + MOVD 8(R12), R2 + MOVD R0, CTR + BL (CTR) + MOVD 40(R1), R2 + RET diff --git a/src/runtime/sys_darwin.go b/src/runtime/sys_darwin.go index 7efbef746c..9b0cc6f935 100644 --- a/src/runtime/sys_darwin.go +++ b/src/runtime/sys_darwin.go @@ -370,5 +370,5 @@ func closeonexec(fd int32) { //go:cgo_import_dynamic libc_pthread_cond_signal pthread_cond_signal "/usr/lib/libSystem.B.dylib" // Magic incantation to get libSystem actually dynamically linked. -// TODO: Why does the code require this? See cmd/compile/internal/ld/go.go:210 +// TODO: Why does the code require this? See cmd/link/internal/ld/go.go //go:cgo_import_dynamic _ _ "/usr/lib/libSystem.B.dylib" diff --git a/src/runtime/sys_dragonfly_amd64.s b/src/runtime/sys_dragonfly_amd64.s index f0eb5f4e21..b771850aaf 100644 --- a/src/runtime/sys_dragonfly_amd64.s +++ b/src/runtime/sys_dragonfly_amd64.s @@ -9,7 +9,7 @@ #include "go_asm.h" #include "go_tls.h" #include "textflag.h" - + TEXT runtime·sys_umtx_sleep(SB),NOSPLIT,$0 MOVQ addr+0(FP), DI // arg 1 - ptr MOVL val+8(FP), SI // arg 2 - value @@ -260,9 +260,11 @@ TEXT runtime·madvise(SB),NOSPLIT,$0 MOVL flags+16(FP), DX MOVQ $75, AX // madvise SYSCALL - // ignore failure - maybe pages are locked + JCC 2(PC) + MOVL $-1, AX + MOVL AX, ret+24(FP) RET - + TEXT runtime·sigaltstack(SB),NOSPLIT,$-8 MOVQ new+0(FP), DI MOVQ old+8(FP), SI diff --git a/src/runtime/sys_freebsd_386.s b/src/runtime/sys_freebsd_386.s index b8f685a323..bc309ba453 100644 --- a/src/runtime/sys_freebsd_386.s +++ b/src/runtime/sys_freebsd_386.s @@ -9,7 +9,7 @@ #include "go_asm.h" #include "go_tls.h" #include "textflag.h" - + TEXT runtime·sys_umtx_op(SB),NOSPLIT,$-4 MOVL $454, AX INT $0x80 @@ -39,7 +39,7 @@ TEXT runtime·thr_start(SB),NOSPLIT,$0 POPAL get_tls(CX) MOVL BX, g(CX) - + MOVL AX, g_m(BX) CALL runtime·stackcheck(SB) // smashes AX CALL runtime·mstart(SB) @@ -163,7 +163,9 @@ TEXT runtime·munmap(SB),NOSPLIT,$-4 TEXT runtime·madvise(SB),NOSPLIT,$-4 MOVL $75, AX // madvise INT $0x80 - // ignore failure - maybe pages are locked + JAE 2(PC) + MOVL $-1, AX + MOVL AX, ret+12(FP) RET TEXT runtime·setitimer(SB), NOSPLIT, $-4 diff --git a/src/runtime/sys_freebsd_amd64.s b/src/runtime/sys_freebsd_amd64.s index be191a0784..55959b3e3a 100644 --- a/src/runtime/sys_freebsd_amd64.s +++ b/src/runtime/sys_freebsd_amd64.s @@ -337,9 +337,11 @@ TEXT runtime·madvise(SB),NOSPLIT,$0 MOVL flags+16(FP), DX MOVQ $75, AX // madvise SYSCALL - // ignore failure - maybe pages are locked + JCC 2(PC) + MOVL $-1, AX + MOVL AX, ret+24(FP) RET - + TEXT runtime·sigaltstack(SB),NOSPLIT,$-8 MOVQ new+0(FP), DI MOVQ old+8(FP), SI diff --git a/src/runtime/sys_freebsd_arm.s b/src/runtime/sys_freebsd_arm.s index 93bf569367..f347b9fa96 100644 --- a/src/runtime/sys_freebsd_arm.s +++ b/src/runtime/sys_freebsd_arm.s @@ -264,14 +264,15 @@ TEXT runtime·munmap(SB),NOSPLIT,$0 RET TEXT runtime·madvise(SB),NOSPLIT,$0 - MOVW addr+0(FP), R0 // arg 1 addr - MOVW n+4(FP), R1 // arg 2 len - MOVW flags+8(FP), R2 // arg 3 flags - MOVW $SYS_madvise, R7 - SWI $0 - // ignore failure - maybe pages are locked + MOVW addr+0(FP), R0 // arg 1 addr + MOVW n+4(FP), R1 // arg 2 len + MOVW flags+8(FP), R2 // arg 3 flags + MOVW $SYS_madvise, R7 + SWI $0 + MOVW.CS $-1, R0 + MOVW R0, ret+12(FP) RET - + TEXT runtime·sigaltstack(SB),NOSPLIT|NOFRAME,$0 MOVW new+0(FP), R0 MOVW old+4(FP), R1 diff --git a/src/runtime/sys_linux_386.s b/src/runtime/sys_linux_386.s index 8d5a4ff977..40b55a67eb 100644 --- a/src/runtime/sys_linux_386.s +++ b/src/runtime/sys_linux_386.s @@ -48,7 +48,6 @@ #define SYS_mincore 218 #define SYS_madvise 219 #define SYS_gettid 224 -#define SYS_tkill 238 #define SYS_futex 240 #define SYS_sched_getaffinity 242 #define SYS_set_thread_area 243 @@ -57,6 +56,7 @@ #define SYS_epoll_ctl 255 #define SYS_epoll_wait 256 #define SYS_clock_gettime 265 +#define SYS_tgkill 270 #define SYS_epoll_create1 329 TEXT runtime·exit(SB),NOSPLIT,$0 @@ -155,11 +155,14 @@ TEXT runtime·gettid(SB),NOSPLIT,$0-4 RET TEXT runtime·raise(SB),NOSPLIT,$12 + MOVL $SYS_getpid, AX + INVOKE_SYSCALL + MOVL AX, BX // arg 1 pid MOVL $SYS_gettid, AX INVOKE_SYSCALL - MOVL AX, BX // arg 1 tid - MOVL sig+0(FP), CX // arg 2 signal - MOVL $SYS_tkill, AX + MOVL AX, CX // arg 2 tid + MOVL sig+0(FP), DX // arg 3 signal + MOVL $SYS_tgkill, AX INVOKE_SYSCALL RET @@ -424,7 +427,7 @@ TEXT runtime·madvise(SB),NOSPLIT,$0 MOVL n+4(FP), CX MOVL flags+8(FP), DX INVOKE_SYSCALL - // ignore failure - maybe pages are locked + MOVL AX, ret+12(FP) RET // int32 futex(int32 *uaddr, int32 op, int32 val, diff --git a/src/runtime/sys_linux_amd64.s b/src/runtime/sys_linux_amd64.s index 62d80247be..b709f77060 100644 --- a/src/runtime/sys_linux_amd64.s +++ b/src/runtime/sys_linux_amd64.s @@ -36,12 +36,12 @@ #define SYS_sigaltstack 131 #define SYS_arch_prctl 158 #define SYS_gettid 186 -#define SYS_tkill 200 #define SYS_futex 202 #define SYS_sched_getaffinity 204 #define SYS_epoll_create 213 #define SYS_exit_group 231 #define SYS_epoll_ctl 233 +#define SYS_tgkill 234 #define SYS_openat 257 #define SYS_faccessat 269 #define SYS_epoll_pwait 281 @@ -137,11 +137,15 @@ TEXT runtime·gettid(SB),NOSPLIT,$0-4 RET TEXT runtime·raise(SB),NOSPLIT,$0 + MOVL $SYS_getpid, AX + SYSCALL + MOVL AX, R12 MOVL $SYS_gettid, AX SYSCALL - MOVL AX, DI // arg 1 tid - MOVL sig+0(FP), SI // arg 2 - MOVL $SYS_tkill, AX + MOVL AX, SI // arg 2 tid + MOVL R12, DI // arg 1 pid + MOVL sig+0(FP), DX // arg 3 + MOVL $SYS_tgkill, AX SYSCALL RET @@ -515,7 +519,7 @@ TEXT runtime·madvise(SB),NOSPLIT,$0 MOVL flags+16(FP), DX MOVQ $SYS_madvise, AX SYSCALL - // ignore failure - maybe pages are locked + MOVL AX, ret+24(FP) RET // int64 futex(int32 *uaddr, int32 op, int32 val, @@ -604,7 +608,7 @@ TEXT runtime·settls(SB),NOSPLIT,$32 // Same as in sys_darwin_386.s:/ugliness, different constant. // DI currently holds m->tls, which must be fs:0x1d0. // See cgo/gcc_android_amd64.c for the derivation of the constant. - SUBQ $0x1d0, DI // In android, the tls base + SUBQ $0x1d0, DI // In android, the tls base #else ADDQ $8, DI // ELF wants to use -8(FS) #endif diff --git a/src/runtime/sys_linux_arm.s b/src/runtime/sys_linux_arm.s index aa39732cfb..43a58335c8 100644 --- a/src/runtime/sys_linux_arm.s +++ b/src/runtime/sys_linux_arm.s @@ -36,7 +36,7 @@ #define SYS_setitimer (SYS_BASE + 104) #define SYS_mincore (SYS_BASE + 219) #define SYS_gettid (SYS_BASE + 224) -#define SYS_tkill (SYS_BASE + 238) +#define SYS_tgkill (SYS_BASE + 268) #define SYS_sched_yield (SYS_BASE + 158) #define SYS_nanosleep (SYS_BASE + 162) #define SYS_sched_getaffinity (SYS_BASE + 242) @@ -138,11 +138,15 @@ TEXT runtime·gettid(SB),NOSPLIT,$0-4 RET TEXT runtime·raise(SB),NOSPLIT|NOFRAME,$0 + MOVW $SYS_getpid, R7 + SWI $0 + MOVW R0, R4 MOVW $SYS_gettid, R7 SWI $0 - // arg 1 tid already in R0 from gettid - MOVW sig+0(FP), R1 // arg 2 - signal - MOVW $SYS_tkill, R7 + MOVW R0, R1 // arg 2 tid + MOVW R4, R0 // arg 1 pid + MOVW sig+0(FP), R2 // arg 3 + MOVW $SYS_tgkill, R7 SWI $0 RET @@ -191,7 +195,7 @@ TEXT runtime·madvise(SB),NOSPLIT,$0 MOVW flags+8(FP), R2 MOVW $SYS_madvise, R7 SWI $0 - // ignore failure - maybe pages are locked + MOVW R0, ret+12(FP) RET TEXT runtime·setitimer(SB),NOSPLIT,$0 diff --git a/src/runtime/sys_linux_arm64.s b/src/runtime/sys_linux_arm64.s index 1c8fce3db6..8b344be8f8 100644 --- a/src/runtime/sys_linux_arm64.s +++ b/src/runtime/sys_linux_arm64.s @@ -36,7 +36,7 @@ #define SYS_getpid 172 #define SYS_gettid 178 #define SYS_kill 129 -#define SYS_tkill 130 +#define SYS_tgkill 131 #define SYS_futex 98 #define SYS_sched_getaffinity 123 #define SYS_exit_group 94 @@ -143,11 +143,15 @@ TEXT runtime·gettid(SB),NOSPLIT,$0-4 RET TEXT runtime·raise(SB),NOSPLIT|NOFRAME,$0 + MOVD $SYS_getpid, R8 + SVC + MOVW R0, R19 MOVD $SYS_gettid, R8 SVC - MOVW R0, R0 // arg 1 tid - MOVW sig+0(FP), R1 // arg 2 - MOVD $SYS_tkill, R8 + MOVW R0, R1 // arg 2 tid + MOVW R19, R0 // arg 1 pid + MOVW sig+0(FP), R2 // arg 3 + MOVD $SYS_tgkill, R8 SVC RET @@ -397,7 +401,7 @@ TEXT runtime·madvise(SB),NOSPLIT|NOFRAME,$0 MOVW flags+16(FP), R2 MOVD $SYS_madvise, R8 SVC - // ignore failure - maybe pages are locked + MOVW R0, ret+24(FP) RET // int64 futex(int32 *uaddr, int32 op, int32 val, diff --git a/src/runtime/sys_linux_mips64x.s b/src/runtime/sys_linux_mips64x.s index 8e64f1c562..c45703d228 100644 --- a/src/runtime/sys_linux_mips64x.s +++ b/src/runtime/sys_linux_mips64x.s @@ -35,12 +35,12 @@ #define SYS_madvise 5027 #define SYS_mincore 5026 #define SYS_gettid 5178 -#define SYS_tkill 5192 #define SYS_futex 5194 #define SYS_sched_getaffinity 5196 #define SYS_exit_group 5205 #define SYS_epoll_create 5207 #define SYS_epoll_ctl 5208 +#define SYS_tgkill 5225 #define SYS_openat 5247 #define SYS_epoll_pwait 5272 #define SYS_clock_gettime 5222 @@ -137,11 +137,15 @@ TEXT runtime·gettid(SB),NOSPLIT,$0-4 RET TEXT runtime·raise(SB),NOSPLIT|NOFRAME,$0 + MOVV $SYS_getpid, R2 + SYSCALL + MOVW R2, R16 MOVV $SYS_gettid, R2 SYSCALL - MOVW R2, R4 // arg 1 tid - MOVW sig+0(FP), R5 // arg 2 - MOVV $SYS_tkill, R2 + MOVW R2, R5 // arg 2 tid + MOVW R16, R4 // arg 1 pid + MOVW sig+0(FP), R6 // arg 3 + MOVV $SYS_tgkill, R2 SYSCALL RET @@ -287,7 +291,7 @@ TEXT runtime·madvise(SB),NOSPLIT|NOFRAME,$0 MOVW flags+16(FP), R6 MOVV $SYS_madvise, R2 SYSCALL - // ignore failure - maybe pages are locked + MOVW R2, ret+24(FP) RET // int64 futex(int32 *uaddr, int32 op, int32 val, diff --git a/src/runtime/sys_linux_mipsx.s b/src/runtime/sys_linux_mipsx.s index a6bca3bebd..f362b0f3f1 100644 --- a/src/runtime/sys_linux_mipsx.s +++ b/src/runtime/sys_linux_mipsx.s @@ -35,7 +35,6 @@ #define SYS_madvise 4218 #define SYS_mincore 4217 #define SYS_gettid 4222 -#define SYS_tkill 4236 #define SYS_futex 4238 #define SYS_sched_getaffinity 4240 #define SYS_exit_group 4246 @@ -43,6 +42,7 @@ #define SYS_epoll_ctl 4249 #define SYS_epoll_wait 4250 #define SYS_clock_gettime 4263 +#define SYS_tgkill 4266 #define SYS_epoll_create1 4326 TEXT runtime·exit(SB),NOSPLIT,$0-4 @@ -135,11 +135,15 @@ TEXT runtime·gettid(SB),NOSPLIT,$0-4 RET TEXT runtime·raise(SB),NOSPLIT,$0-4 + MOVW $SYS_getpid, R2 + SYSCALL + MOVW R2, R16 MOVW $SYS_gettid, R2 SYSCALL - MOVW R2, R4 // arg 1 tid - MOVW sig+0(FP), R5 // arg 2 - MOVW $SYS_tkill, R2 + MOVW R2, R5 // arg 2 tid + MOVW R16, R4 // arg 1 pid + MOVW sig+0(FP), R6 // arg 3 + MOVW $SYS_tgkill, R2 SYSCALL RET @@ -298,13 +302,13 @@ TEXT runtime·munmap(SB),NOSPLIT,$0-8 UNDEF // crash RET -TEXT runtime·madvise(SB),NOSPLIT,$0-12 +TEXT runtime·madvise(SB),NOSPLIT,$0-16 MOVW addr+0(FP), R4 MOVW n+4(FP), R5 MOVW flags+8(FP), R6 MOVW $SYS_madvise, R2 SYSCALL - // ignore failure - maybe pages are locked + MOVW R2, ret+12(FP) RET // int32 futex(int32 *uaddr, int32 op, int32 val, struct timespec *timeout, int32 *uaddr2, int32 val2); diff --git a/src/runtime/sys_linux_ppc64x.s b/src/runtime/sys_linux_ppc64x.s index 075adf2368..ed79b69257 100644 --- a/src/runtime/sys_linux_ppc64x.s +++ b/src/runtime/sys_linux_ppc64x.s @@ -36,7 +36,6 @@ #define SYS_madvise 205 #define SYS_mincore 206 #define SYS_gettid 207 -#define SYS_tkill 208 #define SYS_futex 221 #define SYS_sched_getaffinity 223 #define SYS_exit_group 234 @@ -44,6 +43,7 @@ #define SYS_epoll_ctl 237 #define SYS_epoll_wait 238 #define SYS_clock_gettime 246 +#define SYS_tgkill 250 #define SYS_epoll_create1 315 TEXT runtime·exit(SB),NOSPLIT|NOFRAME,$0-4 @@ -123,10 +123,13 @@ TEXT runtime·gettid(SB),NOSPLIT,$0-4 RET TEXT runtime·raise(SB),NOSPLIT|NOFRAME,$0 + SYSCALL $SYS_getpid + MOVW R3, R14 SYSCALL $SYS_gettid - MOVW R3, R3 // arg 1 tid - MOVW sig+0(FP), R4 // arg 2 - SYSCALL $SYS_tkill + MOVW R3, R4 // arg 2 tid + MOVW R14, R3 // arg 1 pid + MOVW sig+0(FP), R5 // arg 3 + SYSCALL $SYS_tgkill RET TEXT runtime·raiseproc(SB),NOSPLIT|NOFRAME,$0 @@ -451,7 +454,7 @@ TEXT runtime·madvise(SB),NOSPLIT|NOFRAME,$0 MOVD n+8(FP), R4 MOVW flags+16(FP), R5 SYSCALL $SYS_madvise - // ignore failure - maybe pages are locked + MOVW R3, ret+24(FP) RET // int64 futex(int32 *uaddr, int32 op, int32 val, diff --git a/src/runtime/sys_linux_s390x.s b/src/runtime/sys_linux_s390x.s index 1ff110c232..c79ceea751 100644 --- a/src/runtime/sys_linux_s390x.s +++ b/src/runtime/sys_linux_s390x.s @@ -31,9 +31,9 @@ #define SYS_madvise 219 #define SYS_mincore 218 #define SYS_gettid 236 -#define SYS_tkill 237 #define SYS_futex 238 #define SYS_sched_getaffinity 240 +#define SYS_tgkill 241 #define SYS_exit_group 248 #define SYS_epoll_create 249 #define SYS_epoll_ctl 250 @@ -129,11 +129,15 @@ TEXT runtime·gettid(SB),NOSPLIT,$0-4 RET TEXT runtime·raise(SB),NOSPLIT|NOFRAME,$0 + MOVW $SYS_getpid, R1 + SYSCALL + MOVW R2, R10 MOVW $SYS_gettid, R1 SYSCALL - MOVW R2, R2 // arg 1 tid - MOVW sig+0(FP), R3 // arg 2 - MOVW $SYS_tkill, R1 + MOVW R2, R3 // arg 2 tid + MOVW R10, R2 // arg 1 pid + MOVW sig+0(FP), R4 // arg 2 + MOVW $SYS_tgkill, R1 SYSCALL RET @@ -286,7 +290,7 @@ TEXT runtime·madvise(SB),NOSPLIT|NOFRAME,$0 MOVW flags+16(FP), R4 MOVW $SYS_madvise, R1 SYSCALL - // ignore failure - maybe pages are locked + MOVW R2, ret+24(FP) RET // int64 futex(int32 *uaddr, int32 op, int32 val, diff --git a/src/runtime/sys_nacl_386.s b/src/runtime/sys_nacl_386.s index cdc8ff1a02..24eaeb238c 100644 --- a/src/runtime/sys_nacl_386.s +++ b/src/runtime/sys_nacl_386.s @@ -266,7 +266,7 @@ TEXT runtime·nacl_clock_gettime(SB),NOSPLIT,$8 NACL_SYSCALL(SYS_clock_gettime) MOVL AX, ret+8(FP) RET - + TEXT runtime·nanotime(SB),NOSPLIT,$20 MOVL $0, 0(SP) // real time clock LEAL 8(SP), AX @@ -308,12 +308,12 @@ TEXT runtime·sigtramp(SB),NOSPLIT,$0 // save g MOVL DI, 20(SP) - + // g = m->gsignal MOVL g_m(DI), BX MOVL m_gsignal(BX), BX MOVL BX, g(CX) - + // copy arguments for sighandler MOVL $11, 0(SP) // signal MOVL $0, 4(SP) // siginfo @@ -356,7 +356,7 @@ ret: // Today those registers are just PC and SP, but in case additional registers // are relevant in the future (for example DX is the Go func context register) // we restore as many registers as possible. - // + // // We smash BP, because that's what the linker smashes during RET. // LEAL ctxt+4(FP), BP diff --git a/src/runtime/sys_nacl_amd64p32.s b/src/runtime/sys_nacl_amd64p32.s index 4c4d509576..b4a108346d 100644 --- a/src/runtime/sys_nacl_amd64p32.s +++ b/src/runtime/sys_nacl_amd64p32.s @@ -334,13 +334,13 @@ TEXT runtime·sigtramp(SB),NOSPLIT,$80 // check that g exists get_tls(CX) MOVL g(CX), DI - + CMPL DI, $0 JEQ nog // save g MOVL DI, 20(SP) - + // g = m->gsignal MOVL g_m(DI), BX MOVL m_gsignal(BX), BX diff --git a/src/runtime/sys_netbsd_386.s b/src/runtime/sys_netbsd_386.s index 4042ab4f8a..66f4620cab 100644 --- a/src/runtime/sys_netbsd_386.s +++ b/src/runtime/sys_netbsd_386.s @@ -135,7 +135,9 @@ TEXT runtime·munmap(SB),NOSPLIT,$-4 TEXT runtime·madvise(SB),NOSPLIT,$-4 MOVL $75, AX // sys_madvise INT $0x80 - // ignore failure - maybe pages are locked + JAE 2(PC) + MOVL $-1, AX + MOVL AX, ret+12(FP) RET TEXT runtime·setitimer(SB),NOSPLIT,$-4 diff --git a/src/runtime/sys_netbsd_amd64.s b/src/runtime/sys_netbsd_amd64.s index 11b9c1b417..531c227a7b 100644 --- a/src/runtime/sys_netbsd_amd64.s +++ b/src/runtime/sys_netbsd_amd64.s @@ -23,7 +23,7 @@ TEXT runtime·lwp_create(SB),NOSPLIT,$0 RET TEXT runtime·lwp_tramp(SB),NOSPLIT,$0 - + // Set FS to point at m->tls. LEAQ m_tls(R8), DI CALL runtime·settls(SB) @@ -319,7 +319,9 @@ TEXT runtime·madvise(SB),NOSPLIT,$0 MOVL flags+16(FP), DX // arg 3 - behav MOVQ $75, AX // sys_madvise SYSCALL - // ignore failure - maybe pages are locked + JCC 2(PC) + MOVL $-1, AX + MOVL AX, ret+24(FP) RET TEXT runtime·sigaltstack(SB),NOSPLIT,$-8 diff --git a/src/runtime/sys_netbsd_arm.s b/src/runtime/sys_netbsd_arm.s index 6b2c5a8357..304075f295 100644 --- a/src/runtime/sys_netbsd_arm.s +++ b/src/runtime/sys_netbsd_arm.s @@ -284,11 +284,12 @@ TEXT runtime·munmap(SB),NOSPLIT,$0 RET TEXT runtime·madvise(SB),NOSPLIT,$0 - MOVW addr+0(FP), R0 // arg 1 - addr - MOVW n+4(FP), R1 // arg 2 - len - MOVW flags+8(FP), R2 // arg 3 - behav - SWI $0xa0004b // sys_madvise - // ignore failure - maybe pages are locked + MOVW addr+0(FP), R0 // arg 1 - addr + MOVW n+4(FP), R1 // arg 2 - len + MOVW flags+8(FP), R2 // arg 3 - behav + SWI $0xa0004b // sys_madvise + MOVW.CS $-1, R0 + MOVW R0, ret+12(FP) RET TEXT runtime·sigaltstack(SB),NOSPLIT|NOFRAME,$0 diff --git a/src/runtime/sys_openbsd_386.s b/src/runtime/sys_openbsd_386.s index 21f13c806e..d555edb71f 100644 --- a/src/runtime/sys_openbsd_386.s +++ b/src/runtime/sys_openbsd_386.s @@ -136,7 +136,8 @@ TEXT runtime·madvise(SB),NOSPLIT,$-4 MOVL $75, AX // sys_madvise INT $0x80 JAE 2(PC) - MOVL $0xf1, 0xf1 // crash + MOVL $-1, AX + MOVL AX, ret+12(FP) RET TEXT runtime·setitimer(SB),NOSPLIT,$-4 @@ -294,7 +295,7 @@ TEXT runtime·tfork(SB),NOSPLIT,$12 CALL runtime·settls(SB) POPL AX POPAL - + // Now segment is established. Initialize m, g. get_tls(AX) MOVL DX, g(AX) diff --git a/src/runtime/sys_openbsd_amd64.s b/src/runtime/sys_openbsd_amd64.s index 38ac38d9bf..227e81869c 100644 --- a/src/runtime/sys_openbsd_amd64.s +++ b/src/runtime/sys_openbsd_amd64.s @@ -305,7 +305,9 @@ TEXT runtime·madvise(SB),NOSPLIT,$0 MOVL flags+16(FP), DX // arg 3 - behav MOVQ $75, AX // sys_madvise SYSCALL - // ignore failure - maybe pages are locked + JCC 2(PC) + MOVL $-1, AX + MOVL AX, ret+24(FP) RET TEXT runtime·sigaltstack(SB),NOSPLIT,$-8 diff --git a/src/runtime/sys_openbsd_arm.s b/src/runtime/sys_openbsd_arm.s index ff1c1da9b9..52d3638bc1 100644 --- a/src/runtime/sys_openbsd_arm.s +++ b/src/runtime/sys_openbsd_arm.s @@ -143,8 +143,8 @@ TEXT runtime·madvise(SB),NOSPLIT,$0 MOVW flags+8(FP), R2 // arg 2 - flags MOVW $75, R12 // sys_madvise SWI $0 - MOVW.CS $0, R8 // crash on syscall failure - MOVW.CS R8, (R8) + MOVW.CS $-1, R0 + MOVW R0, ret+12(FP) RET TEXT runtime·setitimer(SB),NOSPLIT,$0 diff --git a/src/runtime/sys_plan9_386.s b/src/runtime/sys_plan9_386.s index 47dcb8db04..a7fb9fe6f7 100644 --- a/src/runtime/sys_plan9_386.s +++ b/src/runtime/sys_plan9_386.s @@ -126,7 +126,7 @@ TEXT runtime·noted(SB),NOSPLIT,$0 INT $64 MOVL AX, ret+4(FP) RET - + TEXT runtime·plan9_semrelease(SB),NOSPLIT,$0 MOVL $38, AX INT $64 diff --git a/src/runtime/sys_plan9_amd64.s b/src/runtime/sys_plan9_amd64.s index 8077d6d324..4ef4aab376 100644 --- a/src/runtime/sys_plan9_amd64.s +++ b/src/runtime/sys_plan9_amd64.s @@ -123,7 +123,7 @@ TEXT runtime·noted(SB),NOSPLIT,$0 SYSCALL MOVL AX, ret+8(FP) RET - + TEXT runtime·plan9_semrelease(SB),NOSPLIT,$0 MOVQ $38, BP SYSCALL diff --git a/src/runtime/sys_solaris_amd64.s b/src/runtime/sys_solaris_amd64.s index 2b6dabab99..930fc88997 100644 --- a/src/runtime/sys_solaris_amd64.s +++ b/src/runtime/sys_solaris_amd64.s @@ -63,9 +63,9 @@ TEXT runtime·pipe1(SB),NOSPLIT,$0 // Call a library function with SysV calling conventions. // The called function can take a maximum of 6 INTEGER class arguments, -// see +// see // Michael Matz, Jan Hubicka, Andreas Jaeger, and Mark Mitchell -// System V Application Binary Interface +// System V Application Binary Interface // AMD64 Architecture Processor Supplement // section 3.2.3. // @@ -119,7 +119,7 @@ skipargs: MOVL 0(AX), AX MOVQ AX, libcall_err(DI) -skiperrno2: +skiperrno2: RET // uint32 tstart_sysvicall(M *newm); @@ -186,7 +186,7 @@ allgood: // Save m->libcall and m->scratch. We need to do this because we // might get interrupted by a signal in runtime·asmcgocall. - // save m->libcall + // save m->libcall MOVQ g_m(R10), BP LEAQ m_libcall(BP), R11 MOVQ libcall_fn(R11), R10 diff --git a/src/runtime/sys_windows_386.s b/src/runtime/sys_windows_386.s index 3c091adcb1..babd91c936 100644 --- a/src/runtime/sys_windows_386.s +++ b/src/runtime/sys_windows_386.s @@ -494,13 +494,13 @@ wall: MOVL (_SYSTEM_TIME+time_hi2), DX CMPL CX, DX JNE wall - + // w = DX:AX // convert to Unix epoch (but still 100ns units) #define delta 116444736000000000 SUBL $(delta & 0xFFFFFFFF), AX SBBL $(delta >> 32), DX - + // nano/100 = DX:AX // split into two decimal halves by div 1e9. // (decimal point is two spots over from correct place, @@ -509,7 +509,7 @@ wall: DIVL CX MOVL AX, DI MOVL DX, SI - + // DI = nano/100/1e9 = nano/1e11 = sec/100, DX = SI = nano/100%1e9 // split DX into seconds and nanoseconds by div 1e7 magic multiply. MOVL DX, AX @@ -520,7 +520,7 @@ wall: IMULL $10000000, DX MOVL SI, CX SUBL DX, CX - + // DI = sec/100 (still) // BX = (nano/100%1e9)/1e7 = (nano/1e9)%100 = sec%100 // CX = (nano/100%1e9)%1e7 = (nano%1e9)/100 = nsec/100 diff --git a/src/runtime/sys_windows_amd64.s b/src/runtime/sys_windows_amd64.s index c9127ac2d2..ec49caa43e 100644 --- a/src/runtime/sys_windows_amd64.s +++ b/src/runtime/sys_windows_amd64.s @@ -89,7 +89,7 @@ TEXT runtime·badsignal2(SB),NOSPLIT|NOFRAME,$48 MOVQ $0, 32(SP) // overlapped MOVQ runtime·_WriteFile(SB), AX CALL AX - + RET // faster get/set last error diff --git a/src/runtime/sys_windows_arm.s b/src/runtime/sys_windows_arm.s new file mode 100644 index 0000000000..409c72c554 --- /dev/null +++ b/src/runtime/sys_windows_arm.s @@ -0,0 +1,605 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go_asm.h" +#include "go_tls.h" +#include "textflag.h" + +// void runtime·asmstdcall(void *c); +TEXT runtime·asmstdcall(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4, R5, R14], (R13) // push {r4, r5, lr} + MOVW R0, R4 // put libcall * in r4 + MOVW R13, R5 // save stack pointer in r5 + + // SetLastError(0) + MOVW $0, R0 + MRC 15, 0, R1, C13, C0, 2 + MOVW R0, 0x34(R1) + + MOVW 8(R4), R12 // libcall->args + + // Do we have more than 4 arguments? + MOVW 4(R4), R0 // libcall->n + SUB.S $4, R0, R2 + BLE loadregs + + // Reserve stack space for remaining args + SUB R2<<2, R13 + BIC $0x7, R13 // alignment for ABI + + // R0: count of arguments + // R1: + // R2: loop counter, from 0 to (n-4) + // R3: scratch + // R4: pointer to libcall struct + // R12: libcall->args + MOVW $0, R2 +stackargs: + ADD $4, R2, R3 // r3 = args[4 + i] + MOVW R3<<2(R12), R3 + MOVW R3, R2<<2(R13) // stack[i] = r3 + + ADD $1, R2 // i++ + SUB $4, R0, R3 // while (i < (n - 4)) + CMP R3, R2 + BLT stackargs + +loadregs: + CMP $3, R0 + MOVW.GT 12(R12), R3 + + CMP $2, R0 + MOVW.GT 8(R12), R2 + + CMP $1, R0 + MOVW.GT 4(R12), R1 + + CMP $0, R0 + MOVW.GT 0(R12), R0 + + BIC $0x7, R13 // alignment for ABI + MOVW 0(R4), R12 // branch to libcall->fn + BL (R12) + + MOVW R5, R13 // free stack space + MOVW R0, 12(R4) // save return value to libcall->r1 + MOVW R1, 16(R4) + + // GetLastError + MRC 15, 0, R1, C13, C0, 2 + MOVW 0x34(R1), R0 + MOVW R0, 20(R4) // store in libcall->err + + MOVM.IA.W (R13), [R4, R5, R15] + +TEXT runtime·badsignal2(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4, R14], (R13) // push {r4, lr} + MOVW R13, R4 // save original stack pointer + SUB $8, R13 // space for 2 variables + BIC $0x7, R13 // alignment for ABI + + // stderr + MOVW runtime·_GetStdHandle(SB), R1 + MOVW $-12, R0 + BL (R1) + + MOVW $runtime·badsignalmsg(SB), R1 // lpBuffer + MOVW $runtime·badsignallen(SB), R2 // lpNumberOfBytesToWrite + MOVW (R2), R2 + ADD $0x4, R13, R3 // lpNumberOfBytesWritten + MOVW $0, R12 // lpOverlapped + MOVW R12, (R13) + + MOVW runtime·_WriteFile(SB), R12 + BL (R12) + + MOVW R4, R13 // restore SP + MOVM.IA.W (R13), [R4, R15] // pop {r4, pc} + +TEXT runtime·getlasterror(SB),NOSPLIT,$0 + MRC 15, 0, R0, C13, C0, 2 + MOVW 0x34(R0), R0 + MOVW R0, ret+0(FP) + RET + +TEXT runtime·setlasterror(SB),NOSPLIT|NOFRAME,$0 + MRC 15, 0, R1, C13, C0, 2 + MOVW R0, 0x34(R1) + RET + +// Called by Windows as a Vectored Exception Handler (VEH). +// First argument is pointer to struct containing +// exception record and context pointers. +// Handler function is stored in R1 +// Return 0 for 'not handled', -1 for handled. +// int32_t sigtramp( +// PEXCEPTION_POINTERS ExceptionInfo, +// func *GoExceptionHandler); +TEXT runtime·sigtramp(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R0, R4-R11, R14], (R13) // push {r0, r4-r11, lr} (SP-=40) + SUB $(8+20), R13 // reserve space for g, sp, and + // parameters/retval to go call + + MOVW R0, R6 // Save param0 + MOVW R1, R7 // Save param1 + + BL runtime·load_g(SB) + CMP $0, g // is there a current g? + BL.EQ runtime·badsignal2(SB) + + // save g and SP in case of stack switch + MOVW R13, 24(R13) + MOVW g, 20(R13) + + // do we need to switch to the g0 stack? + MOVW g, R5 // R5 = g + MOVW g_m(R5), R2 // R2 = m + MOVW m_g0(R2), R4 // R4 = g0 + CMP R5, R4 // if curg == g0 + BEQ g0 + + // switch to g0 stack + MOVW R4, g // g = g0 + MOVW (g_sched+gobuf_sp)(g), R3 // R3 = g->gobuf.sp + BL runtime·save_g(SB) + + // traceback will think that we've done PUSH and SUB + // on this stack, so subtract them here to match. + // (we need room for sighandler arguments anyway). + // and re-save old SP for restoring later. + SUB $(40+8+20), R3 + MOVW R13, 24(R3) // save old stack pointer + MOVW R3, R13 // switch stack + +g0: + MOVW 0(R6), R2 // R2 = ExceptionPointers->ExceptionRecord + MOVW 4(R6), R3 // R3 = ExceptionPointers->ContextRecord + + // make it look like mstart called us on g0, to stop traceback + MOVW $runtime·mstart(SB), R4 + + MOVW R4, 0(R13) // Save link register for traceback + MOVW R2, 4(R13) // Move arg0 (ExceptionRecord) into position + MOVW R3, 8(R13) // Move arg1 (ContextRecord) into position + MOVW R5, 12(R13) // Move arg2 (original g) into position + BL (R7) // Call the go routine + MOVW 16(R13), R4 // Fetch return value from stack + + // Compute the value of the g0 stack pointer after deallocating + // this frame, then allocating 8 bytes. We may need to store + // the resume SP and PC on the g0 stack to work around + // control flow guard when we resume from the exception. + ADD $(40+20), R13, R12 + + // switch back to original stack and g + MOVW 24(R13), R13 + MOVW 20(R13), g + BL runtime·save_g(SB) + +done: + MOVW R4, R0 // move retval into position + ADD $(8 + 20), R13 // free locals + MOVM.IA.W (R13), [R3, R4-R11, R14] // pop {r3, r4-r11, lr} + + // if return value is CONTINUE_SEARCH, do not set up control + // flow guard workaround + CMP $0, R0 + BEQ return + + // Check if we need to set up the control flow guard workaround. + // On Windows/ARM, the stack pointer must lie within system + // stack limits when we resume from exception. + // Store the resume SP and PC on the g0 stack, + // and return to returntramp on the g0 stack. returntramp + // pops the saved PC and SP from the g0 stack, resuming execution + // at the desired location. + // If returntramp has already been set up by a previous exception + // handler, don't clobber the stored SP and PC on the stack. + MOVW 4(R3), R3 // PEXCEPTION_POINTERS->Context + MOVW 0x40(R3), R2 // load PC from context record + MOVW $runtime·returntramp(SB), R1 + CMP R1, R2 + B.EQ return // do not clobber saved SP/PC + + // Save resume SP and PC on g0 stack + MOVW 0x38(R3), R2 // load SP from context record + MOVW R2, 0(R12) // Store resume SP on g0 stack + MOVW 0x40(R3), R2 // load PC from context record + MOVW R2, 4(R12) // Store resume PC on g0 stack + + // Set up context record to return to returntramp on g0 stack + MOVW R12, 0x38(R3) // save g0 stack pointer + // in context record + MOVW $runtime·returntramp(SB), R2 // save resume address + MOVW R2, 0x40(R3) // in context record + +return: + B (R14) // return + +// +// Trampoline to resume execution from exception handler. +// This is part of the control flow guard workaround. +// It switches stacks and jumps to the continuation address. +// +TEXT runtime·returntramp(SB),NOSPLIT|NOFRAME,$0 + MOVM.IA (R13), [R13, R15] // ldm sp, [sp, pc] + +TEXT runtime·exceptiontramp(SB),NOSPLIT|NOFRAME,$0 + MOVW $runtime·exceptionhandler(SB), R1 + B runtime·sigtramp(SB) + +TEXT runtime·firstcontinuetramp(SB),NOSPLIT|NOFRAME,$0 + MOVW $runtime·firstcontinuehandler(SB), R1 + B runtime·sigtramp(SB) + +TEXT runtime·lastcontinuetramp(SB),NOSPLIT|NOFRAME,$0 + MOVW $runtime·lastcontinuehandler(SB), R1 + B runtime·sigtramp(SB) + +TEXT runtime·ctrlhandler(SB),NOSPLIT|NOFRAME,$0 + MOVW $runtime·ctrlhandler1(SB), R1 + B runtime·externalthreadhandler(SB) + +TEXT runtime·profileloop(SB),NOSPLIT|NOFRAME,$0 + MOVW $runtime·profileloop1(SB), R1 + B runtime·externalthreadhandler(SB) + +// int32 externalthreadhandler(uint32 arg, int (*func)(uint32)) +// stack layout: +// +----------------+ +// | callee-save | +// | registers | +// +----------------+ +// | m | +// +----------------+ +// 20| g | +// +----------------+ +// 16| func ptr (r1) | +// +----------------+ +// 12| argument (r0) | +//---+----------------+ +// 8 | param1 | +// +----------------+ +// 4 | param0 | +// +----------------+ +// 0 | retval | +// +----------------+ +// +TEXT runtime·externalthreadhandler(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4-R11, R14], (R13) // push {r4-r11, lr} + SUB $(m__size + g__size + 20), R13 // space for locals + MOVW R0, 12(R13) + MOVW R1, 16(R13) + + // zero out m and g structures + ADD $20, R13, R0 // compute pointer to g + MOVW R0, 4(R13) + MOVW $(m__size + g__size), R0 + MOVW R0, 8(R13) + BL runtime·memclrNoHeapPointers(SB) + + // initialize m and g structures + ADD $20, R13, R2 // R2 = g + ADD $(20 + g__size), R13, R3 // R3 = m + MOVW R2, m_g0(R3) // m->g0 = g + MOVW R3, g_m(R2) // g->m = m + MOVW R2, m_curg(R3) // m->curg = g + + MOVW R2, g + BL runtime·save_g(SB) + + // set up stackguard stuff + MOVW R13, R0 + MOVW R0, g_stack+stack_hi(g) + SUB $(32*1024), R0 + MOVW R0, (g_stack+stack_lo)(g) + MOVW R0, g_stackguard0(g) + MOVW R0, g_stackguard1(g) + + // move argument into position and call function + MOVW 12(R13), R0 + MOVW R0, 4(R13) + MOVW 16(R13), R1 + BL (R1) + + // clear g + MOVW $0, g + BL runtime·save_g(SB) + + MOVW 0(R13), R0 // load return value + ADD $(m__size + g__size + 20), R13 // free locals + MOVM.IA.W (R13), [R4-R11, R15] // pop {r4-r11, pc} + +GLOBL runtime·cbctxts(SB), NOPTR, $4 + +TEXT runtime·callbackasm1(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4-R11, R14], (R13) // push {r4-r11, lr} + SUB $36, R13 // space for locals + + // save callback arguments to stack. We currently support up to 4 arguments + ADD $16, R13, R4 + MOVM.IA [R0-R3], (R4) + + // load cbctxts[i]. The trampoline in zcallback_windows.s puts the callback + // index in R12 + MOVW runtime·cbctxts(SB), R4 + MOVW R12<<2(R4), R4 // R4 holds pointer to wincallbackcontext structure + + // extract callback context + MOVW wincallbackcontext_argsize(R4), R5 + MOVW wincallbackcontext_gobody(R4), R4 + + // we currently support up to 4 arguments + CMP $(4 * 4), R5 + BL.GT runtime·abort(SB) + + // extend argsize by size of return value + ADD $4, R5 + + // Build 'type args struct' + MOVW R4, 4(R13) // fn + ADD $16, R13, R0 // arg (points to r0-r3, ret on stack) + MOVW R0, 8(R13) + MOVW R5, 12(R13) // argsize + + BL runtime·load_g(SB) + BL runtime·cgocallback_gofunc(SB) + + ADD $16, R13, R0 // load arg + MOVW 12(R13), R1 // load argsize + SUB $4, R1 // offset to return value + MOVW R1<<0(R0), R0 // load return value + + ADD $36, R13 // free locals + MOVM.IA.W (R13), [R4-R11, R15] // pop {r4-r11, pc} + +// uint32 tstart_stdcall(M *newm); +TEXT runtime·tstart_stdcall(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4-R11, R14], (R13) // push {r4-r11, lr} + + MOVW m_g0(R0), g + MOVW R0, g_m(g) + BL runtime·save_g(SB) + + // Layout new m scheduler stack on os stack. + MOVW R13, R0 + MOVW R0, g_stack+stack_hi(g) + SUB $(64*1024), R0 + MOVW R0, (g_stack+stack_lo)(g) + MOVW R0, g_stackguard0(g) + MOVW R0, g_stackguard1(g) + + BL runtime·emptyfunc(SB) // fault if stack check is wrong + BL runtime·mstart(SB) + + // Exit the thread. + MOVW $0, R0 + MOVM.IA.W (R13), [R4-R11, R15] // pop {r4-r11, pc} + +// onosstack calls fn on OS stack. +// adapted from asm_arm.s : systemstack +// func onosstack(fn unsafe.Pointer, arg uint32) +TEXT runtime·onosstack(SB),NOSPLIT,$0 + MOVW fn+0(FP), R5 // R5 = fn + MOVW arg+4(FP), R6 // R6 = arg + + // This function can be called when there is no g, + // for example, when we are handling a callback on a non-go thread. + // In this case we're already on the system stack. + CMP $0, g + BEQ noswitch + + MOVW g_m(g), R1 // R1 = m + + MOVW m_gsignal(R1), R2 // R2 = gsignal + CMP g, R2 + B.EQ noswitch + + MOVW m_g0(R1), R2 // R2 = g0 + CMP g, R2 + B.EQ noswitch + + MOVW m_curg(R1), R3 + CMP g, R3 + B.EQ switch + + // Bad: g is not gsignal, not g0, not curg. What is it? + // Hide call from linker nosplit analysis. + MOVW $runtime·badsystemstack(SB), R0 + BL (R0) + B runtime·abort(SB) + +switch: + // save our state in g->sched. Pretend to + // be systemstack_switch if the G stack is scanned. + MOVW $runtime·systemstack_switch(SB), R3 + ADD $4, R3, R3 // get past push {lr} + MOVW R3, (g_sched+gobuf_pc)(g) + MOVW R13, (g_sched+gobuf_sp)(g) + MOVW LR, (g_sched+gobuf_lr)(g) + MOVW g, (g_sched+gobuf_g)(g) + + // switch to g0 + MOVW R2, g + MOVW (g_sched+gobuf_sp)(R2), R3 + // make it look like mstart called systemstack on g0, to stop traceback + SUB $4, R3, R3 + MOVW $runtime·mstart(SB), R4 + MOVW R4, 0(R3) + MOVW R3, R13 + + // call target function + MOVW R6, R0 // arg + BL (R5) + + // switch back to g + MOVW g_m(g), R1 + MOVW m_curg(R1), g + MOVW (g_sched+gobuf_sp)(g), R13 + MOVW $0, R3 + MOVW R3, (g_sched+gobuf_sp)(g) + RET + +noswitch: + // Using a tail call here cleans up tracebacks since we won't stop + // at an intermediate systemstack. + MOVW.P 4(R13), R14 // restore LR + MOVW R6, R0 // arg + B (R5) + +// Runs on OS stack. Duration (in 100ns units) is in R0. +TEXT runtime·usleep2(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4, R14], (R13) // push {r4, lr} + MOVW R13, R4 // Save SP + SUB $8, R13 // R13 = R13 - 8 + BIC $0x7, R13 // Align SP for ABI + RSB $0, R0, R3 // R3 = -R0 + MOVW $0, R1 // R1 = FALSE (alertable) + MOVW $-1, R0 // R0 = handle + MOVW R13, R2 // R2 = pTime + MOVW R3, 0(R2) // time_lo + MOVW R0, 4(R2) // time_hi + MOVW runtime·_NtWaitForSingleObject(SB), R3 + BL (R3) + MOVW R4, R13 // Restore SP + MOVM.IA.W (R13), [R4, R15] // pop {R4, pc} + +// Runs on OS stack. +TEXT runtime·switchtothread(SB),NOSPLIT|NOFRAME,$0 + MOVM.DB.W [R4, R14], (R13) // push {R4, lr} + MOVW R13, R4 + BIC $0x7, R13 // alignment for ABI + MOVW runtime·_SwitchToThread(SB), R0 + BL (R0) + MOVW R4, R13 // restore stack pointer + MOVM.IA.W (R13), [R4, R15] // pop {R4, pc} + +TEXT ·publicationBarrier(SB),NOSPLIT|NOFRAME,$0-0 + B runtime·armPublicationBarrier(SB) + +// never called (cgo not supported) +TEXT runtime·read_tls_fallback(SB),NOSPLIT|NOFRAME,$0 + MOVW $0xabcd, R0 + MOVW R0, (R0) + RET + +// See http://www.dcl.hpi.uni-potsdam.de/research/WRK/2007/08/getting-os-information-the-kuser_shared_data-structure/ +// Must read hi1, then lo, then hi2. The snapshot is valid if hi1 == hi2. +#define _INTERRUPT_TIME 0x7ffe0008 +#define _SYSTEM_TIME 0x7ffe0014 +#define time_lo 0 +#define time_hi1 4 +#define time_hi2 8 + +TEXT runtime·nanotime(SB),NOSPLIT,$0-8 + MOVW $0, R0 + MOVB runtime·useQPCTime(SB), R0 + CMP $0, R0 + BNE useQPC + MOVW $_INTERRUPT_TIME, R3 +loop: + MOVW time_hi1(R3), R1 + MOVW time_lo(R3), R0 + MOVW time_hi2(R3), R2 + CMP R1, R2 + BNE loop + + // wintime = R1:R0, multiply by 100 + MOVW $100, R2 + MULLU R0, R2, (R4, R3) // R4:R3 = R1:R0 * R2 + MULA R1, R2, R4, R4 + + // wintime*100 = R4:R3, subtract startNano and return + MOVW runtime·startNano+0(SB), R0 + MOVW runtime·startNano+4(SB), R1 + SUB.S R0, R3 + SBC R1, R4 + MOVW R3, ret_lo+0(FP) + MOVW R4, ret_hi+4(FP) + RET +useQPC: + B runtime·nanotimeQPC(SB) // tail call + RET + +TEXT time·now(SB),NOSPLIT,$0-20 + MOVW $0, R0 + MOVB runtime·useQPCTime(SB), R0 + CMP $0, R0 + BNE useQPC + MOVW $_INTERRUPT_TIME, R3 +loop: + MOVW time_hi1(R3), R1 + MOVW time_lo(R3), R0 + MOVW time_hi2(R3), R2 + CMP R1, R2 + BNE loop + + // wintime = R1:R0, multiply by 100 + MOVW $100, R2 + MULLU R0, R2, (R4, R3) // R4:R3 = R1:R0 * R2 + MULA R1, R2, R4, R4 + + // wintime*100 = R4:R3, subtract startNano and return + MOVW runtime·startNano+0(SB), R0 + MOVW runtime·startNano+4(SB), R1 + SUB.S R0, R3 + SBC R1, R4 + MOVW R3, mono+12(FP) + MOVW R4, mono+16(FP) + + MOVW $_SYSTEM_TIME, R3 +wall: + MOVW time_hi1(R3), R1 + MOVW time_lo(R3), R0 + MOVW time_hi2(R3), R2 + CMP R1, R2 + BNE wall + + // w = R1:R0 in 100ns untis + // convert to Unix epoch (but still 100ns units) + #define delta 116444736000000000 + SUB.S $(delta & 0xFFFFFFFF), R0 + SBC $(delta >> 32), R1 + + // Convert to nSec + MOVW $100, R2 + MULLU R0, R2, (R4, R3) // R4:R3 = R1:R0 * R2 + MULA R1, R2, R4, R4 + // w = R2:R1 in nSec + MOVW R3, R1 // R4:R3 -> R2:R1 + MOVW R4, R2 + + // multiply nanoseconds by reciprocal of 10**9 (scaled by 2**61) + // to get seconds (96 bit scaled result) + MOVW $0x89705f41, R3 // 2**61 * 10**-9 + MULLU R1,R3,(R6,R5) // R7:R6:R5 = R2:R1 * R3 + MOVW $0,R7 + MULALU R2,R3,(R7,R6) + + // unscale by discarding low 32 bits, shifting the rest by 29 + MOVW R6>>29,R6 // R7:R6 = (R7:R6:R5 >> 61) + ORR R7<<3,R6 + MOVW R7>>29,R7 + + // subtract (10**9 * sec) from nsec to get nanosecond remainder + MOVW $1000000000, R5 // 10**9 + MULLU R6,R5,(R9,R8) // R9:R8 = R7:R6 * R5 + MULA R7,R5,R9,R9 + SUB.S R8,R1 // R2:R1 -= R9:R8 + SBC R9,R2 + + // because reciprocal was a truncated repeating fraction, quotient + // may be slightly too small -- adjust to make remainder < 10**9 + CMP R5,R1 // if remainder > 10**9 + SUB.HS R5,R1 // remainder -= 10**9 + ADD.HS $1,R6 // sec += 1 + + MOVW R6,sec_lo+0(FP) + MOVW R7,sec_hi+4(FP) + MOVW R1,nsec+8(FP) + RET +useQPC: + B runtime·nanotimeQPC(SB) // tail call + RET + diff --git a/src/runtime/syscall_windows.go b/src/runtime/syscall_windows.go index 8264070569..0858efaf61 100644 --- a/src/runtime/syscall_windows.go +++ b/src/runtime/syscall_windows.go @@ -25,18 +25,32 @@ func (c *wincallbackcontext) setCleanstack(cleanstack bool) { var ( cbs callbacks cbctxts **wincallbackcontext = &cbs.ctxt[0] // to simplify access to cbs.ctxt in sys_windows_*.s - - callbackasm byte // type isn't really byte, it's code in runtime ) +func callbackasm() + // callbackasmAddr returns address of runtime.callbackasm // function adjusted by i. -// runtime.callbackasm is just a series of CALL instructions -// (each is 5 bytes long), and we want callback to arrive at +// On x86 and amd64, runtime.callbackasm is a series of CALL instructions, +// and we want callback to arrive at // correspondent call instruction instead of start of // runtime.callbackasm. +// On ARM, runtime.callbackasm is a series of mov and branch instructions. +// R12 is loaded with the callback index. Each entry is two instructions, +// hence 8 bytes. func callbackasmAddr(i int) uintptr { - return uintptr(add(unsafe.Pointer(&callbackasm), uintptr(i*5))) + var entrySize int + switch GOARCH { + default: + panic("unsupported architecture") + case "386", "amd64": + entrySize = 5 + case "arm": + // On ARM, each entry is a MOV instruction + // followed by a branch instruction + entrySize = 8 + } + return funcPC(callbackasm) + uintptr(i*entrySize) } //go:linkname compileCallback syscall.compileCallback diff --git a/src/runtime/testdata/testprogcgo/exec.go b/src/runtime/testdata/testprogcgo/exec.go index 2e948401c8..94da5dc526 100644 --- a/src/runtime/testdata/testprogcgo/exec.go +++ b/src/runtime/testdata/testprogcgo/exec.go @@ -75,6 +75,14 @@ func CgoExecSignalMask() { cmd.Stdout = os.Stdout cmd.Stderr = os.Stderr if err := cmd.Run(); err != nil { + // An overloaded system + // may fail with EAGAIN. + // This doesn't tell us + // anything useful; ignore it. + // Issue #27731. + if isEAGAIN(err) { + return + } fmt.Printf("iteration %d: %v\n", j, err) os.Exit(1) } @@ -87,3 +95,11 @@ func CgoExecSignalMask() { fmt.Println("OK") } + +// isEAGAIN reports whether err is an EAGAIN error from a process execution. +func isEAGAIN(err error) bool { + if p, ok := err.(*os.PathError); ok { + err = p.Err + } + return err == syscall.EAGAIN +} diff --git a/src/runtime/timestub2.go b/src/runtime/timestub2.go index 9ddc6fed91..00c2c55f46 100644 --- a/src/runtime/timestub2.go +++ b/src/runtime/timestub2.go @@ -5,6 +5,7 @@ // +build !darwin // +build !windows // +build !freebsd +// +build !aix package runtime diff --git a/src/runtime/tls_arm.s b/src/runtime/tls_arm.s index cc547a5db1..e2c945d183 100644 --- a/src/runtime/tls_arm.s +++ b/src/runtime/tls_arm.s @@ -23,6 +23,9 @@ #ifdef GOOS_darwin #define TLSG_IS_VARIABLE #endif +#ifdef GOOS_windows +#define TLSG_IS_VARIABLE +#endif // save_g saves the g register into pthread-provided // thread-local memory, so that we can call externally compiled @@ -36,6 +39,17 @@ TEXT runtime·save_g(SB),NOSPLIT|NOFRAME,$0 MOVW g, R0 // preserve R0 across call to setg<> RET #else +#ifdef GOOS_windows + // Save the value in the _TEB->TlsSlots array. + // Effectively implements TlsSetValue(). + MRC 15, 0, R0, C13, C0, 2 + ADD $0xe10, R0 + MOVW $runtime·tls_g(SB), R11 + MOVW (R11), R11 + MOVW g, R11<<2(R0) + MOVW g, R0 // preserve R0 accross call to setg<> + RET +#else // If the host does not support MRC the linker will replace it with // a call to runtime.read_tls_fallback which jumps to __kuser_get_tls. // The replacement function saves LR in R11 over the call to read_tls_fallback. @@ -47,6 +61,7 @@ TEXT runtime·save_g(SB),NOSPLIT|NOFRAME,$0 MOVW g, R0 // preserve R0 across call to setg<> RET #endif +#endif // load_g loads the g register from pthread-provided // thread-local memory, for use after calling externally compiled @@ -56,6 +71,16 @@ TEXT runtime·load_g(SB),NOSPLIT,$0 // nothing to do as nacl/arm does not use TLS at all. RET #else +#ifdef GOOS_windows + // Get the value from the _TEB->TlsSlots array. + // Effectively implements TlsGetValue(). + MRC 15, 0, R0, C13, C0, 2 + ADD $0xe10, R0 + MOVW $runtime·tls_g(SB), g + MOVW (g), g + MOVW g<<2(R0), g + RET +#else // See save_g MRC 15, 0, R0, C13, C0, 3 // fetch TLS base pointer BIC $3, R0 // Darwin/ARM might return unaligned pointer @@ -64,6 +89,7 @@ TEXT runtime·load_g(SB),NOSPLIT,$0 MOVW 0(R0), g RET #endif +#endif // This is called from rt0_go, which runs on the system stack // using the initial stack allocated by the OS. @@ -76,6 +102,20 @@ TEXT runtime·load_g(SB),NOSPLIT,$0 // Declare a dummy word ($4, not $0) to make sure the // frame is 8 bytes and stays 8-byte-aligned. TEXT runtime·_initcgo(SB),NOSPLIT,$4 +#ifdef GOOS_windows + MOVW R13, R4 + BIC $0x7, R13 + MOVW $runtime·_TlsAlloc(SB), R0 + MOVW (R0), R0 + BL (R0) + // Assert that slot is less than 64 so we can use _TEB->TlsSlots + CMP $64, R0 + MOVW $runtime·abort(SB), R1 + BL.GE (R1) + MOVW $runtime·tls_g(SB), R1 + MOVW R0, (R1) + MOVW R4, R13 +#else #ifndef GOOS_nacl // if there is an _cgo_init, call it. MOVW _cgo_init(SB), R4 @@ -91,7 +131,8 @@ TEXT runtime·_initcgo(SB),NOSPLIT,$4 MOVW $setg_gcc<>(SB), R1 // arg 1: setg MOVW g, R0 // arg 0: G BL (R4) // will clobber R0-R3 -#endif +#endif // GOOS_nacl +#endif // GOOS_windows nocgo: RET diff --git a/src/runtime/traceback.go b/src/runtime/traceback.go index 4c2010493a..d7265b2bb9 100644 --- a/src/runtime/traceback.go +++ b/src/runtime/traceback.go @@ -312,8 +312,7 @@ func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max in // the function either doesn't return at all (if it has no defers or if the // defers do not recover) or it returns from one of the calls to // deferproc a second time (if the corresponding deferred func recovers). - // It suffices to assume that the most recent deferproc is the one that - // returns; everything live at earlier deferprocs is still live at that one. + // In the latter case, use a deferreturn call site as the continuation pc. frame.continpc = frame.pc if waspanic { // We match up defers with frames using the SP. @@ -324,7 +323,10 @@ func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max in // can't push a defer, the defer can't belong // to that frame. if _defer != nil && _defer.sp == frame.sp && frame.sp != frame.fp { - frame.continpc = _defer.pc + frame.continpc = frame.fn.entry + uintptr(frame.fn.deferreturn) + 1 + // Note: the +1 is to offset the -1 that + // stack.go:getStackMap does to back up a return + // address make sure the pc is in the CALL instruction. } else { frame.continpc = 0 } @@ -571,8 +573,9 @@ func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max in // reflectMethodValue is a partial duplicate of reflect.makeFuncImpl // and reflect.methodValue. type reflectMethodValue struct { - fn uintptr - stack *bitvector // args bitmap + fn uintptr + stack *bitvector // ptrmap for both args and results + argLen uintptr // just args } // getArgInfoFast returns the argument frame information for a call to f. @@ -601,6 +604,7 @@ func getArgInfo(frame *stkframe, f funcInfo, needArgMap bool, ctxt *funcval) (ar // These take a *reflect.methodValue as their // context register. var mv *reflectMethodValue + var retValid bool if ctxt != nil { // This is not an actual call, but a // deferred call. The function value @@ -614,6 +618,10 @@ func getArgInfo(frame *stkframe, f funcInfo, needArgMap bool, ctxt *funcval) (ar // 0(SP). arg0 := frame.sp + sys.MinFrameSize mv = *(**reflectMethodValue)(unsafe.Pointer(arg0)) + // Figure out whether the return values are valid. + // Reflect will update this value after it copies + // in the return values. + retValid = *(*bool)(unsafe.Pointer(arg0 + 3*sys.PtrSize)) } if mv.fn != f.entry { print("runtime: confused by ", funcname(f), "\n") @@ -621,6 +629,9 @@ func getArgInfo(frame *stkframe, f funcInfo, needArgMap bool, ctxt *funcval) (ar } bv := mv.stack arglen = uintptr(bv.n * sys.PtrSize) + if !retValid { + arglen = uintptr(mv.argLen) &^ (sys.PtrSize - 1) + } argmap = bv } } @@ -936,7 +947,7 @@ func tracebackothers(me *g) { lock(&allglock) for _, gp := range allgs { - if gp == me || gp == g.m.curg || readgstatus(gp) == _Gdead || isSystemGoroutine(gp) && level < 2 { + if gp == me || gp == g.m.curg || readgstatus(gp) == _Gdead || isSystemGoroutine(gp, false) && level < 2 { continue } print("\n") @@ -1022,7 +1033,11 @@ func topofstack(f funcInfo, g0 bool) bool { // in stack dumps and deadlock detector. This is any goroutine that // starts at a runtime.* entry point, except for runtime.main and // sometimes runtime.runfinq. -func isSystemGoroutine(gp *g) bool { +// +// If fixed is true, any goroutine that can vary between user and +// system (that is, the finalizer goroutine) is considered a user +// goroutine. +func isSystemGoroutine(gp *g, fixed bool) bool { // Keep this in sync with cmd/trace/trace.go:isSystemGoroutine. f := findfunc(gp.startpc) if !f.valid() { @@ -1034,6 +1049,11 @@ func isSystemGoroutine(gp *g) bool { if f.funcID == funcID_runfinq { // We include the finalizer goroutine if it's calling // back into user code. + if fixed { + // This goroutine can vary. In fixed mode, + // always consider it a user goroutine. + return false + } return !fingRunning } return hasPrefix(funcname(f), "runtime.") diff --git a/src/runtime/vlop_arm.s b/src/runtime/vlop_arm.s index 729653488f..41d285874d 100644 --- a/src/runtime/vlop_arm.s +++ b/src/runtime/vlop_arm.s @@ -30,7 +30,7 @@ // func runtime·udiv(n, d uint32) (q, r uint32) // compiler knowns the register usage of this function -// Reference: +// Reference: // Sloss, Andrew et. al; ARM System Developer's Guide: Designing and Optimizing System Software // Morgan Kaufmann; 1 edition (April 8, 2004), ISBN 978-1558608740 #define Rq R0 // input d, output q diff --git a/src/runtime/wincallback.go b/src/runtime/wincallback.go index 9f003aed05..c022916422 100644 --- a/src/runtime/wincallback.go +++ b/src/runtime/wincallback.go @@ -17,11 +17,12 @@ import ( const maxCallback = 2000 -func genasm() { +func genasm386Amd64() { var buf bytes.Buffer - buf.WriteString(`// generated by wincallback.go; run go generate + buf.WriteString(`// Code generated by wincallback.go using 'go generate'. DO NOT EDIT. +// +build 386 amd64 // runtime·callbackasm is called by external code to // execute Go implemented callback function. It is not // called from the start, instead runtime·compilecallback @@ -29,13 +30,43 @@ func genasm() { // appropriately so different callbacks start with different // CALL instruction in runtime·callbackasm. This determines // which Go callback function is executed later on. + TEXT runtime·callbackasm(SB),7,$0 `) for i := 0; i < maxCallback; i++ { buf.WriteString("\tCALL\truntime·callbackasm1(SB)\n") } - err := ioutil.WriteFile("zcallback_windows.s", buf.Bytes(), 0666) + filename := fmt.Sprintf("zcallback_windows.s") + err := ioutil.WriteFile(filename, buf.Bytes(), 0666) + if err != nil { + fmt.Fprintf(os.Stderr, "wincallback: %s\n", err) + os.Exit(2) + } +} + +func genasmArm() { + var buf bytes.Buffer + + buf.WriteString(`// Code generated by wincallback.go using 'go generate'. DO NOT EDIT. + +// External code calls into callbackasm at an offset corresponding +// to the callback index. Callbackasm is a table of MOV and B instructions. +// The MOV instruction loads R12 with the callback index, and the +// B instruction branches to callbackasm1. +// callbackasm1 takes the callback index from R12 and +// indexes into an array that stores information about each callback. +// It then calls the Go implementation for that callback. +#include "textflag.h" + +TEXT runtime·callbackasm(SB),NOSPLIT|NOFRAME,$0 +`) + for i := 0; i < maxCallback; i++ { + buf.WriteString(fmt.Sprintf("\tMOVW\t$%d, R12\n", i)) + buf.WriteString("\tB\truntime·callbackasm1(SB)\n") + } + + err := ioutil.WriteFile("zcallback_windows_arm.s", buf.Bytes(), 0666) if err != nil { fmt.Fprintf(os.Stderr, "wincallback: %s\n", err) os.Exit(2) @@ -45,7 +76,7 @@ TEXT runtime·callbackasm(SB),7,$0 func gengo() { var buf bytes.Buffer - buf.WriteString(fmt.Sprintf(`// generated by wincallback.go; run go generate + buf.WriteString(fmt.Sprintf(`// Code generated by wincallback.go using 'go generate'. DO NOT EDIT. package runtime @@ -59,6 +90,7 @@ const cb_max = %d // maximum number of windows callbacks allowed } func main() { - genasm() + genasm386Amd64() + genasmArm() gengo() } diff --git a/src/runtime/zcallback_windows.go b/src/runtime/zcallback_windows.go index 9908d4ec23..2c3cb28518 100644 --- a/src/runtime/zcallback_windows.go +++ b/src/runtime/zcallback_windows.go @@ -1,4 +1,4 @@ -// generated by wincallback.go; run go generate +// Code generated by wincallback.go using 'go generate'. DO NOT EDIT. package runtime diff --git a/src/runtime/zcallback_windows.s b/src/runtime/zcallback_windows.s index b9a3a30811..7772eef329 100644 --- a/src/runtime/zcallback_windows.s +++ b/src/runtime/zcallback_windows.s @@ -1,5 +1,6 @@ -// generated by wincallback.go; run go generate +// Code generated by wincallback.go using 'go generate'. DO NOT EDIT. +// +build 386 amd64 // runtime·callbackasm is called by external code to // execute Go implemented callback function. It is not // called from the start, instead runtime·compilecallback @@ -7,6 +8,7 @@ // appropriately so different callbacks start with different // CALL instruction in runtime·callbackasm. This determines // which Go callback function is executed later on. + TEXT runtime·callbackasm(SB),7,$0 CALL runtime·callbackasm1(SB) CALL runtime·callbackasm1(SB) diff --git a/src/runtime/zcallback_windows_arm.s b/src/runtime/zcallback_windows_arm.s new file mode 100644 index 0000000000..f943d84cbf --- /dev/null +++ b/src/runtime/zcallback_windows_arm.s @@ -0,0 +1,4012 @@ +// Code generated by wincallback.go using 'go generate'. DO NOT EDIT. + +// External code calls into callbackasm at an offset corresponding +// to the callback index. Callbackasm is a table of MOV and B instructions. +// The MOV instruction loads R12 with the callback index, and the +// B instruction branches to callbackasm1. +// callbackasm1 takes the callback index from R12 and +// indexes into an array that stores information about each callback. +// It then calls the Go implementation for that callback. +#include "textflag.h" + +TEXT runtime·callbackasm(SB),NOSPLIT|NOFRAME,$0 + MOVW $0, R12 + B runtime·callbackasm1(SB) + MOVW $1, R12 + B runtime·callbackasm1(SB) + MOVW $2, R12 + B runtime·callbackasm1(SB) + MOVW $3, R12 + B runtime·callbackasm1(SB) + MOVW $4, R12 + B runtime·callbackasm1(SB) + MOVW $5, R12 + B runtime·callbackasm1(SB) + MOVW $6, R12 + B runtime·callbackasm1(SB) + MOVW $7, R12 + B runtime·callbackasm1(SB) + MOVW $8, R12 + B runtime·callbackasm1(SB) + MOVW $9, R12 + B runtime·callbackasm1(SB) + MOVW $10, R12 + B runtime·callbackasm1(SB) + MOVW $11, R12 + B runtime·callbackasm1(SB) + MOVW $12, R12 + B runtime·callbackasm1(SB) + MOVW $13, R12 + B runtime·callbackasm1(SB) + MOVW $14, R12 + B runtime·callbackasm1(SB) + MOVW $15, R12 + B runtime·callbackasm1(SB) + MOVW $16, R12 + B runtime·callbackasm1(SB) + MOVW $17, R12 + B runtime·callbackasm1(SB) + MOVW $18, R12 + B runtime·callbackasm1(SB) + MOVW $19, R12 + B runtime·callbackasm1(SB) + MOVW $20, R12 + B runtime·callbackasm1(SB) + MOVW $21, R12 + B runtime·callbackasm1(SB) + MOVW $22, R12 + B runtime·callbackasm1(SB) + MOVW $23, R12 + B runtime·callbackasm1(SB) + MOVW $24, R12 + B runtime·callbackasm1(SB) + MOVW $25, R12 + B runtime·callbackasm1(SB) + MOVW $26, R12 + B runtime·callbackasm1(SB) + MOVW $27, R12 + B runtime·callbackasm1(SB) + MOVW $28, R12 + B runtime·callbackasm1(SB) + MOVW $29, R12 + B runtime·callbackasm1(SB) + MOVW $30, R12 + B runtime·callbackasm1(SB) + MOVW $31, R12 + B runtime·callbackasm1(SB) + MOVW $32, R12 + B runtime·callbackasm1(SB) + MOVW $33, R12 + B runtime·callbackasm1(SB) + MOVW $34, R12 + B runtime·callbackasm1(SB) + MOVW $35, R12 + B runtime·callbackasm1(SB) + MOVW $36, R12 + B runtime·callbackasm1(SB) + MOVW $37, R12 + B runtime·callbackasm1(SB) + MOVW $38, R12 + B runtime·callbackasm1(SB) + MOVW $39, R12 + B runtime·callbackasm1(SB) + MOVW $40, R12 + B runtime·callbackasm1(SB) + MOVW $41, R12 + B runtime·callbackasm1(SB) + MOVW $42, R12 + B runtime·callbackasm1(SB) + MOVW $43, R12 + B runtime·callbackasm1(SB) + MOVW $44, R12 + B runtime·callbackasm1(SB) + MOVW $45, R12 + B runtime·callbackasm1(SB) + MOVW $46, R12 + B runtime·callbackasm1(SB) + MOVW $47, R12 + B runtime·callbackasm1(SB) + MOVW $48, R12 + B runtime·callbackasm1(SB) + MOVW $49, R12 + B runtime·callbackasm1(SB) + MOVW $50, R12 + B runtime·callbackasm1(SB) + MOVW $51, R12 + B runtime·callbackasm1(SB) + MOVW $52, R12 + B runtime·callbackasm1(SB) + MOVW $53, R12 + B runtime·callbackasm1(SB) + MOVW $54, R12 + B runtime·callbackasm1(SB) + MOVW $55, R12 + B runtime·callbackasm1(SB) + MOVW $56, R12 + B runtime·callbackasm1(SB) + MOVW $57, R12 + B runtime·callbackasm1(SB) + MOVW $58, R12 + B runtime·callbackasm1(SB) + MOVW $59, R12 + B runtime·callbackasm1(SB) + MOVW $60, R12 + B runtime·callbackasm1(SB) + MOVW $61, R12 + B runtime·callbackasm1(SB) + MOVW $62, R12 + B runtime·callbackasm1(SB) + MOVW $63, R12 + B runtime·callbackasm1(SB) + MOVW $64, R12 + B runtime·callbackasm1(SB) + MOVW $65, R12 + B runtime·callbackasm1(SB) + MOVW $66, R12 + B runtime·callbackasm1(SB) + MOVW $67, R12 + B runtime·callbackasm1(SB) + MOVW $68, R12 + B runtime·callbackasm1(SB) + MOVW $69, R12 + B runtime·callbackasm1(SB) + MOVW $70, R12 + B runtime·callbackasm1(SB) + MOVW $71, R12 + B runtime·callbackasm1(SB) + MOVW $72, R12 + B runtime·callbackasm1(SB) + MOVW $73, R12 + B runtime·callbackasm1(SB) + MOVW $74, R12 + B runtime·callbackasm1(SB) + MOVW $75, R12 + B runtime·callbackasm1(SB) + MOVW $76, R12 + B runtime·callbackasm1(SB) + MOVW $77, R12 + B runtime·callbackasm1(SB) + MOVW $78, R12 + B runtime·callbackasm1(SB) + MOVW $79, R12 + B runtime·callbackasm1(SB) + MOVW $80, R12 + B runtime·callbackasm1(SB) + MOVW $81, R12 + B runtime·callbackasm1(SB) + MOVW $82, R12 + B runtime·callbackasm1(SB) + MOVW $83, R12 + B runtime·callbackasm1(SB) + MOVW $84, R12 + B runtime·callbackasm1(SB) + MOVW $85, R12 + B runtime·callbackasm1(SB) + MOVW $86, R12 + B runtime·callbackasm1(SB) + MOVW $87, R12 + B runtime·callbackasm1(SB) + MOVW $88, R12 + B runtime·callbackasm1(SB) + MOVW $89, R12 + B runtime·callbackasm1(SB) + MOVW $90, R12 + B runtime·callbackasm1(SB) + MOVW $91, R12 + B runtime·callbackasm1(SB) + MOVW $92, R12 + B runtime·callbackasm1(SB) + MOVW $93, R12 + B runtime·callbackasm1(SB) + MOVW $94, R12 + B runtime·callbackasm1(SB) + MOVW $95, R12 + B runtime·callbackasm1(SB) + MOVW $96, R12 + B runtime·callbackasm1(SB) + MOVW $97, R12 + B runtime·callbackasm1(SB) + MOVW $98, R12 + B runtime·callbackasm1(SB) + MOVW $99, R12 + B runtime·callbackasm1(SB) + MOVW $100, R12 + B runtime·callbackasm1(SB) + MOVW $101, R12 + B runtime·callbackasm1(SB) + MOVW $102, R12 + B runtime·callbackasm1(SB) + MOVW $103, R12 + B runtime·callbackasm1(SB) + MOVW $104, R12 + B runtime·callbackasm1(SB) + MOVW $105, R12 + B runtime·callbackasm1(SB) + MOVW $106, R12 + B runtime·callbackasm1(SB) + MOVW $107, R12 + B runtime·callbackasm1(SB) + MOVW $108, R12 + B runtime·callbackasm1(SB) + MOVW $109, R12 + B runtime·callbackasm1(SB) + MOVW $110, R12 + B runtime·callbackasm1(SB) + MOVW $111, R12 + B runtime·callbackasm1(SB) + MOVW $112, R12 + B runtime·callbackasm1(SB) + MOVW $113, R12 + B runtime·callbackasm1(SB) + MOVW $114, R12 + B runtime·callbackasm1(SB) + MOVW $115, R12 + B runtime·callbackasm1(SB) + MOVW $116, R12 + B runtime·callbackasm1(SB) + MOVW $117, R12 + B runtime·callbackasm1(SB) + MOVW $118, R12 + B runtime·callbackasm1(SB) + MOVW $119, R12 + B runtime·callbackasm1(SB) + MOVW $120, R12 + B runtime·callbackasm1(SB) + MOVW $121, R12 + B runtime·callbackasm1(SB) + MOVW $122, R12 + B runtime·callbackasm1(SB) + MOVW $123, R12 + B runtime·callbackasm1(SB) + MOVW $124, R12 + B runtime·callbackasm1(SB) + MOVW $125, R12 + B runtime·callbackasm1(SB) + MOVW $126, R12 + B runtime·callbackasm1(SB) + MOVW $127, R12 + B runtime·callbackasm1(SB) + MOVW $128, R12 + B runtime·callbackasm1(SB) + MOVW $129, R12 + B runtime·callbackasm1(SB) + MOVW $130, R12 + B runtime·callbackasm1(SB) + MOVW $131, R12 + B runtime·callbackasm1(SB) + MOVW $132, R12 + B runtime·callbackasm1(SB) + MOVW $133, R12 + B runtime·callbackasm1(SB) + MOVW $134, R12 + B runtime·callbackasm1(SB) + MOVW $135, R12 + B runtime·callbackasm1(SB) + MOVW $136, R12 + B runtime·callbackasm1(SB) + MOVW $137, R12 + B runtime·callbackasm1(SB) + MOVW $138, R12 + B runtime·callbackasm1(SB) + MOVW $139, R12 + B runtime·callbackasm1(SB) + MOVW $140, R12 + B runtime·callbackasm1(SB) + MOVW $141, R12 + B runtime·callbackasm1(SB) + MOVW $142, R12 + B runtime·callbackasm1(SB) + MOVW $143, R12 + B runtime·callbackasm1(SB) + MOVW $144, R12 + B runtime·callbackasm1(SB) + MOVW $145, R12 + B runtime·callbackasm1(SB) + MOVW $146, R12 + B runtime·callbackasm1(SB) + MOVW $147, R12 + B runtime·callbackasm1(SB) + MOVW $148, R12 + B runtime·callbackasm1(SB) + MOVW $149, R12 + B runtime·callbackasm1(SB) + MOVW $150, R12 + B runtime·callbackasm1(SB) + MOVW $151, R12 + B runtime·callbackasm1(SB) + MOVW $152, R12 + B runtime·callbackasm1(SB) + MOVW $153, R12 + B runtime·callbackasm1(SB) + MOVW $154, R12 + B runtime·callbackasm1(SB) + MOVW $155, R12 + B runtime·callbackasm1(SB) + MOVW $156, R12 + B runtime·callbackasm1(SB) + MOVW $157, R12 + B runtime·callbackasm1(SB) + MOVW $158, R12 + B runtime·callbackasm1(SB) + MOVW $159, R12 + B runtime·callbackasm1(SB) + MOVW $160, R12 + B runtime·callbackasm1(SB) + MOVW $161, R12 + B runtime·callbackasm1(SB) + MOVW $162, R12 + B runtime·callbackasm1(SB) + MOVW $163, R12 + B runtime·callbackasm1(SB) + MOVW $164, R12 + B runtime·callbackasm1(SB) + MOVW $165, R12 + B runtime·callbackasm1(SB) + MOVW $166, R12 + B runtime·callbackasm1(SB) + MOVW $167, R12 + B runtime·callbackasm1(SB) + MOVW $168, R12 + B runtime·callbackasm1(SB) + MOVW $169, R12 + B runtime·callbackasm1(SB) + MOVW $170, R12 + B runtime·callbackasm1(SB) + MOVW $171, R12 + B runtime·callbackasm1(SB) + MOVW $172, R12 + B runtime·callbackasm1(SB) + MOVW $173, R12 + B runtime·callbackasm1(SB) + MOVW $174, R12 + B runtime·callbackasm1(SB) + MOVW $175, R12 + B runtime·callbackasm1(SB) + MOVW $176, R12 + B runtime·callbackasm1(SB) + MOVW $177, R12 + B runtime·callbackasm1(SB) + MOVW $178, R12 + B runtime·callbackasm1(SB) + MOVW $179, R12 + B runtime·callbackasm1(SB) + MOVW $180, R12 + B runtime·callbackasm1(SB) + MOVW $181, R12 + B runtime·callbackasm1(SB) + MOVW $182, R12 + B runtime·callbackasm1(SB) + MOVW $183, R12 + B runtime·callbackasm1(SB) + MOVW $184, R12 + B runtime·callbackasm1(SB) + MOVW $185, R12 + B runtime·callbackasm1(SB) + MOVW $186, R12 + B runtime·callbackasm1(SB) + MOVW $187, R12 + B runtime·callbackasm1(SB) + MOVW $188, R12 + B runtime·callbackasm1(SB) + MOVW $189, R12 + B runtime·callbackasm1(SB) + MOVW $190, R12 + B runtime·callbackasm1(SB) + MOVW $191, R12 + B runtime·callbackasm1(SB) + MOVW $192, R12 + B runtime·callbackasm1(SB) + MOVW $193, R12 + B runtime·callbackasm1(SB) + MOVW $194, R12 + B runtime·callbackasm1(SB) + MOVW $195, R12 + B runtime·callbackasm1(SB) + MOVW $196, R12 + B runtime·callbackasm1(SB) + MOVW $197, R12 + B runtime·callbackasm1(SB) + MOVW $198, R12 + B runtime·callbackasm1(SB) + MOVW $199, R12 + B runtime·callbackasm1(SB) + MOVW $200, R12 + B runtime·callbackasm1(SB) + MOVW $201, R12 + B runtime·callbackasm1(SB) + MOVW $202, R12 + B runtime·callbackasm1(SB) + MOVW $203, R12 + B runtime·callbackasm1(SB) + MOVW $204, R12 + B runtime·callbackasm1(SB) + MOVW $205, R12 + B runtime·callbackasm1(SB) + MOVW $206, R12 + B runtime·callbackasm1(SB) + MOVW $207, R12 + B runtime·callbackasm1(SB) + MOVW $208, R12 + B runtime·callbackasm1(SB) + MOVW $209, R12 + B runtime·callbackasm1(SB) + MOVW $210, R12 + B runtime·callbackasm1(SB) + MOVW $211, R12 + B runtime·callbackasm1(SB) + MOVW $212, R12 + B runtime·callbackasm1(SB) + MOVW $213, R12 + B runtime·callbackasm1(SB) + MOVW $214, R12 + B runtime·callbackasm1(SB) + MOVW $215, R12 + B runtime·callbackasm1(SB) + MOVW $216, R12 + B runtime·callbackasm1(SB) + MOVW $217, R12 + B runtime·callbackasm1(SB) + MOVW $218, R12 + B runtime·callbackasm1(SB) + MOVW $219, R12 + B runtime·callbackasm1(SB) + MOVW $220, R12 + B runtime·callbackasm1(SB) + MOVW $221, R12 + B runtime·callbackasm1(SB) + MOVW $222, R12 + B runtime·callbackasm1(SB) + MOVW $223, R12 + B runtime·callbackasm1(SB) + MOVW $224, R12 + B runtime·callbackasm1(SB) + MOVW $225, R12 + B runtime·callbackasm1(SB) + MOVW $226, R12 + B runtime·callbackasm1(SB) + MOVW $227, R12 + B runtime·callbackasm1(SB) + MOVW $228, R12 + B runtime·callbackasm1(SB) + MOVW $229, R12 + B runtime·callbackasm1(SB) + MOVW $230, R12 + B runtime·callbackasm1(SB) + MOVW $231, R12 + B runtime·callbackasm1(SB) + MOVW $232, R12 + B runtime·callbackasm1(SB) + MOVW $233, R12 + B runtime·callbackasm1(SB) + MOVW $234, R12 + B runtime·callbackasm1(SB) + MOVW $235, R12 + B runtime·callbackasm1(SB) + MOVW $236, R12 + B runtime·callbackasm1(SB) + MOVW $237, R12 + B runtime·callbackasm1(SB) + MOVW $238, R12 + B runtime·callbackasm1(SB) + MOVW $239, R12 + B runtime·callbackasm1(SB) + MOVW $240, R12 + B runtime·callbackasm1(SB) + MOVW $241, R12 + B runtime·callbackasm1(SB) + MOVW $242, R12 + B runtime·callbackasm1(SB) + MOVW $243, R12 + B runtime·callbackasm1(SB) + MOVW $244, R12 + B runtime·callbackasm1(SB) + MOVW $245, R12 + B runtime·callbackasm1(SB) + MOVW $246, R12 + B runtime·callbackasm1(SB) + MOVW $247, R12 + B runtime·callbackasm1(SB) + MOVW $248, R12 + B runtime·callbackasm1(SB) + MOVW $249, R12 + B runtime·callbackasm1(SB) + MOVW $250, R12 + B runtime·callbackasm1(SB) + MOVW $251, R12 + B runtime·callbackasm1(SB) + MOVW $252, R12 + B runtime·callbackasm1(SB) + MOVW $253, R12 + B runtime·callbackasm1(SB) + MOVW $254, R12 + B runtime·callbackasm1(SB) + MOVW $255, R12 + B runtime·callbackasm1(SB) + MOVW $256, R12 + B runtime·callbackasm1(SB) + MOVW $257, R12 + B runtime·callbackasm1(SB) + MOVW $258, R12 + B runtime·callbackasm1(SB) + MOVW $259, R12 + B runtime·callbackasm1(SB) + MOVW $260, R12 + B runtime·callbackasm1(SB) + MOVW $261, R12 + B runtime·callbackasm1(SB) + MOVW $262, R12 + B runtime·callbackasm1(SB) + MOVW $263, R12 + B runtime·callbackasm1(SB) + MOVW $264, R12 + B runtime·callbackasm1(SB) + MOVW $265, R12 + B runtime·callbackasm1(SB) + MOVW $266, R12 + B runtime·callbackasm1(SB) + MOVW $267, R12 + B runtime·callbackasm1(SB) + MOVW $268, R12 + B runtime·callbackasm1(SB) + MOVW $269, R12 + B runtime·callbackasm1(SB) + MOVW $270, R12 + B runtime·callbackasm1(SB) + MOVW $271, R12 + B runtime·callbackasm1(SB) + MOVW $272, R12 + B runtime·callbackasm1(SB) + MOVW $273, R12 + B runtime·callbackasm1(SB) + MOVW $274, R12 + B runtime·callbackasm1(SB) + MOVW $275, R12 + B runtime·callbackasm1(SB) + MOVW $276, R12 + B runtime·callbackasm1(SB) + MOVW $277, R12 + B runtime·callbackasm1(SB) + MOVW $278, R12 + B runtime·callbackasm1(SB) + MOVW $279, R12 + B runtime·callbackasm1(SB) + MOVW $280, R12 + B runtime·callbackasm1(SB) + MOVW $281, R12 + B runtime·callbackasm1(SB) + MOVW $282, R12 + B runtime·callbackasm1(SB) + MOVW $283, R12 + B runtime·callbackasm1(SB) + MOVW $284, R12 + B runtime·callbackasm1(SB) + MOVW $285, R12 + B runtime·callbackasm1(SB) + MOVW $286, R12 + B runtime·callbackasm1(SB) + MOVW $287, R12 + B runtime·callbackasm1(SB) + MOVW $288, R12 + B runtime·callbackasm1(SB) + MOVW $289, R12 + B runtime·callbackasm1(SB) + MOVW $290, R12 + B runtime·callbackasm1(SB) + MOVW $291, R12 + B runtime·callbackasm1(SB) + MOVW $292, R12 + B runtime·callbackasm1(SB) + MOVW $293, R12 + B runtime·callbackasm1(SB) + MOVW $294, R12 + B runtime·callbackasm1(SB) + MOVW $295, R12 + B runtime·callbackasm1(SB) + MOVW $296, R12 + B runtime·callbackasm1(SB) + MOVW $297, R12 + B runtime·callbackasm1(SB) + MOVW $298, R12 + B runtime·callbackasm1(SB) + MOVW $299, R12 + B runtime·callbackasm1(SB) + MOVW $300, R12 + B runtime·callbackasm1(SB) + MOVW $301, R12 + B runtime·callbackasm1(SB) + MOVW $302, R12 + B runtime·callbackasm1(SB) + MOVW $303, R12 + B runtime·callbackasm1(SB) + MOVW $304, R12 + B runtime·callbackasm1(SB) + MOVW $305, R12 + B runtime·callbackasm1(SB) + MOVW $306, R12 + B runtime·callbackasm1(SB) + MOVW $307, R12 + B runtime·callbackasm1(SB) + MOVW $308, R12 + B runtime·callbackasm1(SB) + MOVW $309, R12 + B runtime·callbackasm1(SB) + MOVW $310, R12 + B runtime·callbackasm1(SB) + MOVW $311, R12 + B runtime·callbackasm1(SB) + MOVW $312, R12 + B runtime·callbackasm1(SB) + MOVW $313, R12 + B runtime·callbackasm1(SB) + MOVW $314, R12 + B runtime·callbackasm1(SB) + MOVW $315, R12 + B runtime·callbackasm1(SB) + MOVW $316, R12 + B runtime·callbackasm1(SB) + MOVW $317, R12 + B runtime·callbackasm1(SB) + MOVW $318, R12 + B runtime·callbackasm1(SB) + MOVW $319, R12 + B runtime·callbackasm1(SB) + MOVW $320, R12 + B runtime·callbackasm1(SB) + MOVW $321, R12 + B runtime·callbackasm1(SB) + MOVW $322, R12 + B runtime·callbackasm1(SB) + MOVW $323, R12 + B runtime·callbackasm1(SB) + MOVW $324, R12 + B runtime·callbackasm1(SB) + MOVW $325, R12 + B runtime·callbackasm1(SB) + MOVW $326, R12 + B runtime·callbackasm1(SB) + MOVW $327, R12 + B runtime·callbackasm1(SB) + MOVW $328, R12 + B runtime·callbackasm1(SB) + MOVW $329, R12 + B runtime·callbackasm1(SB) + MOVW $330, R12 + B runtime·callbackasm1(SB) + MOVW $331, R12 + B runtime·callbackasm1(SB) + MOVW $332, R12 + B runtime·callbackasm1(SB) + MOVW $333, R12 + B runtime·callbackasm1(SB) + MOVW $334, R12 + B runtime·callbackasm1(SB) + MOVW $335, R12 + B runtime·callbackasm1(SB) + MOVW $336, R12 + B runtime·callbackasm1(SB) + MOVW $337, R12 + B runtime·callbackasm1(SB) + MOVW $338, R12 + B runtime·callbackasm1(SB) + MOVW $339, R12 + B runtime·callbackasm1(SB) + MOVW $340, R12 + B runtime·callbackasm1(SB) + MOVW $341, R12 + B runtime·callbackasm1(SB) + MOVW $342, R12 + B runtime·callbackasm1(SB) + MOVW $343, R12 + B runtime·callbackasm1(SB) + MOVW $344, R12 + B runtime·callbackasm1(SB) + MOVW $345, R12 + B runtime·callbackasm1(SB) + MOVW $346, R12 + B runtime·callbackasm1(SB) + MOVW $347, R12 + B runtime·callbackasm1(SB) + MOVW $348, R12 + B runtime·callbackasm1(SB) + MOVW $349, R12 + B runtime·callbackasm1(SB) + MOVW $350, R12 + B runtime·callbackasm1(SB) + MOVW $351, R12 + B runtime·callbackasm1(SB) + MOVW $352, R12 + B runtime·callbackasm1(SB) + MOVW $353, R12 + B runtime·callbackasm1(SB) + MOVW $354, R12 + B runtime·callbackasm1(SB) + MOVW $355, R12 + B runtime·callbackasm1(SB) + MOVW $356, R12 + B runtime·callbackasm1(SB) + MOVW $357, R12 + B runtime·callbackasm1(SB) + MOVW $358, R12 + B runtime·callbackasm1(SB) + MOVW $359, R12 + B runtime·callbackasm1(SB) + MOVW $360, R12 + B runtime·callbackasm1(SB) + MOVW $361, R12 + B runtime·callbackasm1(SB) + MOVW $362, R12 + B runtime·callbackasm1(SB) + MOVW $363, R12 + B runtime·callbackasm1(SB) + MOVW $364, R12 + B runtime·callbackasm1(SB) + MOVW $365, R12 + B runtime·callbackasm1(SB) + MOVW $366, R12 + B runtime·callbackasm1(SB) + MOVW $367, R12 + B runtime·callbackasm1(SB) + MOVW $368, R12 + B runtime·callbackasm1(SB) + MOVW $369, R12 + B runtime·callbackasm1(SB) + MOVW $370, R12 + B runtime·callbackasm1(SB) + MOVW $371, R12 + B runtime·callbackasm1(SB) + MOVW $372, R12 + B runtime·callbackasm1(SB) + MOVW $373, R12 + B runtime·callbackasm1(SB) + MOVW $374, R12 + B runtime·callbackasm1(SB) + MOVW $375, R12 + B runtime·callbackasm1(SB) + MOVW $376, R12 + B runtime·callbackasm1(SB) + MOVW $377, R12 + B runtime·callbackasm1(SB) + MOVW $378, R12 + B runtime·callbackasm1(SB) + MOVW $379, R12 + B runtime·callbackasm1(SB) + MOVW $380, R12 + B runtime·callbackasm1(SB) + MOVW $381, R12 + B runtime·callbackasm1(SB) + MOVW $382, R12 + B runtime·callbackasm1(SB) + MOVW $383, R12 + B runtime·callbackasm1(SB) + MOVW $384, R12 + B runtime·callbackasm1(SB) + MOVW $385, R12 + B runtime·callbackasm1(SB) + MOVW $386, R12 + B runtime·callbackasm1(SB) + MOVW $387, R12 + B runtime·callbackasm1(SB) + MOVW $388, R12 + B runtime·callbackasm1(SB) + MOVW $389, R12 + B runtime·callbackasm1(SB) + MOVW $390, R12 + B runtime·callbackasm1(SB) + MOVW $391, R12 + B runtime·callbackasm1(SB) + MOVW $392, R12 + B runtime·callbackasm1(SB) + MOVW $393, R12 + B runtime·callbackasm1(SB) + MOVW $394, R12 + B runtime·callbackasm1(SB) + MOVW $395, R12 + B runtime·callbackasm1(SB) + MOVW $396, R12 + B runtime·callbackasm1(SB) + MOVW $397, R12 + B runtime·callbackasm1(SB) + MOVW $398, R12 + B runtime·callbackasm1(SB) + MOVW $399, R12 + B runtime·callbackasm1(SB) + MOVW $400, R12 + B runtime·callbackasm1(SB) + MOVW $401, R12 + B runtime·callbackasm1(SB) + MOVW $402, R12 + B runtime·callbackasm1(SB) + MOVW $403, R12 + B runtime·callbackasm1(SB) + MOVW $404, R12 + B runtime·callbackasm1(SB) + MOVW $405, R12 + B runtime·callbackasm1(SB) + MOVW $406, R12 + B runtime·callbackasm1(SB) + MOVW $407, R12 + B runtime·callbackasm1(SB) + MOVW $408, R12 + B runtime·callbackasm1(SB) + MOVW $409, R12 + B runtime·callbackasm1(SB) + MOVW $410, R12 + B runtime·callbackasm1(SB) + MOVW $411, R12 + B runtime·callbackasm1(SB) + MOVW $412, R12 + B runtime·callbackasm1(SB) + MOVW $413, R12 + B runtime·callbackasm1(SB) + MOVW $414, R12 + B runtime·callbackasm1(SB) + MOVW $415, R12 + B runtime·callbackasm1(SB) + MOVW $416, R12 + B runtime·callbackasm1(SB) + MOVW $417, R12 + B runtime·callbackasm1(SB) + MOVW $418, R12 + B runtime·callbackasm1(SB) + MOVW $419, R12 + B runtime·callbackasm1(SB) + MOVW $420, R12 + B runtime·callbackasm1(SB) + MOVW $421, R12 + B runtime·callbackasm1(SB) + MOVW $422, R12 + B runtime·callbackasm1(SB) + MOVW $423, R12 + B runtime·callbackasm1(SB) + MOVW $424, R12 + B runtime·callbackasm1(SB) + MOVW $425, R12 + B runtime·callbackasm1(SB) + MOVW $426, R12 + B runtime·callbackasm1(SB) + MOVW $427, R12 + B runtime·callbackasm1(SB) + MOVW $428, R12 + B runtime·callbackasm1(SB) + MOVW $429, R12 + B runtime·callbackasm1(SB) + MOVW $430, R12 + B runtime·callbackasm1(SB) + MOVW $431, R12 + B runtime·callbackasm1(SB) + MOVW $432, R12 + B runtime·callbackasm1(SB) + MOVW $433, R12 + B runtime·callbackasm1(SB) + MOVW $434, R12 + B runtime·callbackasm1(SB) + MOVW $435, R12 + B runtime·callbackasm1(SB) + MOVW $436, R12 + B runtime·callbackasm1(SB) + MOVW $437, R12 + B runtime·callbackasm1(SB) + MOVW $438, R12 + B runtime·callbackasm1(SB) + MOVW $439, R12 + B runtime·callbackasm1(SB) + MOVW $440, R12 + B runtime·callbackasm1(SB) + MOVW $441, R12 + B runtime·callbackasm1(SB) + MOVW $442, R12 + B runtime·callbackasm1(SB) + MOVW $443, R12 + B runtime·callbackasm1(SB) + MOVW $444, R12 + B runtime·callbackasm1(SB) + MOVW $445, R12 + B runtime·callbackasm1(SB) + MOVW $446, R12 + B runtime·callbackasm1(SB) + MOVW $447, R12 + B runtime·callbackasm1(SB) + MOVW $448, R12 + B runtime·callbackasm1(SB) + MOVW $449, R12 + B runtime·callbackasm1(SB) + MOVW $450, R12 + B runtime·callbackasm1(SB) + MOVW $451, R12 + B runtime·callbackasm1(SB) + MOVW $452, R12 + B runtime·callbackasm1(SB) + MOVW $453, R12 + B runtime·callbackasm1(SB) + MOVW $454, R12 + B runtime·callbackasm1(SB) + MOVW $455, R12 + B runtime·callbackasm1(SB) + MOVW $456, R12 + B runtime·callbackasm1(SB) + MOVW $457, R12 + B runtime·callbackasm1(SB) + MOVW $458, R12 + B runtime·callbackasm1(SB) + MOVW $459, R12 + B runtime·callbackasm1(SB) + MOVW $460, R12 + B runtime·callbackasm1(SB) + MOVW $461, R12 + B runtime·callbackasm1(SB) + MOVW $462, R12 + B runtime·callbackasm1(SB) + MOVW $463, R12 + B runtime·callbackasm1(SB) + MOVW $464, R12 + B runtime·callbackasm1(SB) + MOVW $465, R12 + B runtime·callbackasm1(SB) + MOVW $466, R12 + B runtime·callbackasm1(SB) + MOVW $467, R12 + B runtime·callbackasm1(SB) + MOVW $468, R12 + B runtime·callbackasm1(SB) + MOVW $469, R12 + B runtime·callbackasm1(SB) + MOVW $470, R12 + B runtime·callbackasm1(SB) + MOVW $471, R12 + B runtime·callbackasm1(SB) + MOVW $472, R12 + B runtime·callbackasm1(SB) + MOVW $473, R12 + B runtime·callbackasm1(SB) + MOVW $474, R12 + B runtime·callbackasm1(SB) + MOVW $475, R12 + B runtime·callbackasm1(SB) + MOVW $476, R12 + B runtime·callbackasm1(SB) + MOVW $477, R12 + B runtime·callbackasm1(SB) + MOVW $478, R12 + B runtime·callbackasm1(SB) + MOVW $479, R12 + B runtime·callbackasm1(SB) + MOVW $480, R12 + B runtime·callbackasm1(SB) + MOVW $481, R12 + B runtime·callbackasm1(SB) + MOVW $482, R12 + B runtime·callbackasm1(SB) + MOVW $483, R12 + B runtime·callbackasm1(SB) + MOVW $484, R12 + B runtime·callbackasm1(SB) + MOVW $485, R12 + B runtime·callbackasm1(SB) + MOVW $486, R12 + B runtime·callbackasm1(SB) + MOVW $487, R12 + B runtime·callbackasm1(SB) + MOVW $488, R12 + B runtime·callbackasm1(SB) + MOVW $489, R12 + B runtime·callbackasm1(SB) + MOVW $490, R12 + B runtime·callbackasm1(SB) + MOVW $491, R12 + B runtime·callbackasm1(SB) + MOVW $492, R12 + B runtime·callbackasm1(SB) + MOVW $493, R12 + B runtime·callbackasm1(SB) + MOVW $494, R12 + B runtime·callbackasm1(SB) + MOVW $495, R12 + B runtime·callbackasm1(SB) + MOVW $496, R12 + B runtime·callbackasm1(SB) + MOVW $497, R12 + B runtime·callbackasm1(SB) + MOVW $498, R12 + B runtime·callbackasm1(SB) + MOVW $499, R12 + B runtime·callbackasm1(SB) + MOVW $500, R12 + B runtime·callbackasm1(SB) + MOVW $501, R12 + B runtime·callbackasm1(SB) + MOVW $502, R12 + B runtime·callbackasm1(SB) + MOVW $503, R12 + B runtime·callbackasm1(SB) + MOVW $504, R12 + B runtime·callbackasm1(SB) + MOVW $505, R12 + B runtime·callbackasm1(SB) + MOVW $506, R12 + B runtime·callbackasm1(SB) + MOVW $507, R12 + B runtime·callbackasm1(SB) + MOVW $508, R12 + B runtime·callbackasm1(SB) + MOVW $509, R12 + B runtime·callbackasm1(SB) + MOVW $510, R12 + B runtime·callbackasm1(SB) + MOVW $511, R12 + B runtime·callbackasm1(SB) + MOVW $512, R12 + B runtime·callbackasm1(SB) + MOVW $513, R12 + B runtime·callbackasm1(SB) + MOVW $514, R12 + B runtime·callbackasm1(SB) + MOVW $515, R12 + B runtime·callbackasm1(SB) + MOVW $516, R12 + B runtime·callbackasm1(SB) + MOVW $517, R12 + B runtime·callbackasm1(SB) + MOVW $518, R12 + B runtime·callbackasm1(SB) + MOVW $519, R12 + B runtime·callbackasm1(SB) + MOVW $520, R12 + B runtime·callbackasm1(SB) + MOVW $521, R12 + B runtime·callbackasm1(SB) + MOVW $522, R12 + B runtime·callbackasm1(SB) + MOVW $523, R12 + B runtime·callbackasm1(SB) + MOVW $524, R12 + B runtime·callbackasm1(SB) + MOVW $525, R12 + B runtime·callbackasm1(SB) + MOVW $526, R12 + B runtime·callbackasm1(SB) + MOVW $527, R12 + B runtime·callbackasm1(SB) + MOVW $528, R12 + B runtime·callbackasm1(SB) + MOVW $529, R12 + B runtime·callbackasm1(SB) + MOVW $530, R12 + B runtime·callbackasm1(SB) + MOVW $531, R12 + B runtime·callbackasm1(SB) + MOVW $532, R12 + B runtime·callbackasm1(SB) + MOVW $533, R12 + B runtime·callbackasm1(SB) + MOVW $534, R12 + B runtime·callbackasm1(SB) + MOVW $535, R12 + B runtime·callbackasm1(SB) + MOVW $536, R12 + B runtime·callbackasm1(SB) + MOVW $537, R12 + B runtime·callbackasm1(SB) + MOVW $538, R12 + B runtime·callbackasm1(SB) + MOVW $539, R12 + B runtime·callbackasm1(SB) + MOVW $540, R12 + B runtime·callbackasm1(SB) + MOVW $541, R12 + B runtime·callbackasm1(SB) + MOVW $542, R12 + B runtime·callbackasm1(SB) + MOVW $543, R12 + B runtime·callbackasm1(SB) + MOVW $544, R12 + B runtime·callbackasm1(SB) + MOVW $545, R12 + B runtime·callbackasm1(SB) + MOVW $546, R12 + B runtime·callbackasm1(SB) + MOVW $547, R12 + B runtime·callbackasm1(SB) + MOVW $548, R12 + B runtime·callbackasm1(SB) + MOVW $549, R12 + B runtime·callbackasm1(SB) + MOVW $550, R12 + B runtime·callbackasm1(SB) + MOVW $551, R12 + B runtime·callbackasm1(SB) + MOVW $552, R12 + B runtime·callbackasm1(SB) + MOVW $553, R12 + B runtime·callbackasm1(SB) + MOVW $554, R12 + B runtime·callbackasm1(SB) + MOVW $555, R12 + B runtime·callbackasm1(SB) + MOVW $556, R12 + B runtime·callbackasm1(SB) + MOVW $557, R12 + B runtime·callbackasm1(SB) + MOVW $558, R12 + B runtime·callbackasm1(SB) + MOVW $559, R12 + B runtime·callbackasm1(SB) + MOVW $560, R12 + B runtime·callbackasm1(SB) + MOVW $561, R12 + B runtime·callbackasm1(SB) + MOVW $562, R12 + B runtime·callbackasm1(SB) + MOVW $563, R12 + B runtime·callbackasm1(SB) + MOVW $564, R12 + B runtime·callbackasm1(SB) + MOVW $565, R12 + B runtime·callbackasm1(SB) + MOVW $566, R12 + B runtime·callbackasm1(SB) + MOVW $567, R12 + B runtime·callbackasm1(SB) + MOVW $568, R12 + B runtime·callbackasm1(SB) + MOVW $569, R12 + B runtime·callbackasm1(SB) + MOVW $570, R12 + B runtime·callbackasm1(SB) + MOVW $571, R12 + B runtime·callbackasm1(SB) + MOVW $572, R12 + B runtime·callbackasm1(SB) + MOVW $573, R12 + B runtime·callbackasm1(SB) + MOVW $574, R12 + B runtime·callbackasm1(SB) + MOVW $575, R12 + B runtime·callbackasm1(SB) + MOVW $576, R12 + B runtime·callbackasm1(SB) + MOVW $577, R12 + B runtime·callbackasm1(SB) + MOVW $578, R12 + B runtime·callbackasm1(SB) + MOVW $579, R12 + B runtime·callbackasm1(SB) + MOVW $580, R12 + B runtime·callbackasm1(SB) + MOVW $581, R12 + B runtime·callbackasm1(SB) + MOVW $582, R12 + B runtime·callbackasm1(SB) + MOVW $583, R12 + B runtime·callbackasm1(SB) + MOVW $584, R12 + B runtime·callbackasm1(SB) + MOVW $585, R12 + B runtime·callbackasm1(SB) + MOVW $586, R12 + B runtime·callbackasm1(SB) + MOVW $587, R12 + B runtime·callbackasm1(SB) + MOVW $588, R12 + B runtime·callbackasm1(SB) + MOVW $589, R12 + B runtime·callbackasm1(SB) + MOVW $590, R12 + B runtime·callbackasm1(SB) + MOVW $591, R12 + B runtime·callbackasm1(SB) + MOVW $592, R12 + B runtime·callbackasm1(SB) + MOVW $593, R12 + B runtime·callbackasm1(SB) + MOVW $594, R12 + B runtime·callbackasm1(SB) + MOVW $595, R12 + B runtime·callbackasm1(SB) + MOVW $596, R12 + B runtime·callbackasm1(SB) + MOVW $597, R12 + B runtime·callbackasm1(SB) + MOVW $598, R12 + B runtime·callbackasm1(SB) + MOVW $599, R12 + B runtime·callbackasm1(SB) + MOVW $600, R12 + B runtime·callbackasm1(SB) + MOVW $601, R12 + B runtime·callbackasm1(SB) + MOVW $602, R12 + B runtime·callbackasm1(SB) + MOVW $603, R12 + B runtime·callbackasm1(SB) + MOVW $604, R12 + B runtime·callbackasm1(SB) + MOVW $605, R12 + B runtime·callbackasm1(SB) + MOVW $606, R12 + B runtime·callbackasm1(SB) + MOVW $607, R12 + B runtime·callbackasm1(SB) + MOVW $608, R12 + B runtime·callbackasm1(SB) + MOVW $609, R12 + B runtime·callbackasm1(SB) + MOVW $610, R12 + B runtime·callbackasm1(SB) + MOVW $611, R12 + B runtime·callbackasm1(SB) + MOVW $612, R12 + B runtime·callbackasm1(SB) + MOVW $613, R12 + B runtime·callbackasm1(SB) + MOVW $614, R12 + B runtime·callbackasm1(SB) + MOVW $615, R12 + B runtime·callbackasm1(SB) + MOVW $616, R12 + B runtime·callbackasm1(SB) + MOVW $617, R12 + B runtime·callbackasm1(SB) + MOVW $618, R12 + B runtime·callbackasm1(SB) + MOVW $619, R12 + B runtime·callbackasm1(SB) + MOVW $620, R12 + B runtime·callbackasm1(SB) + MOVW $621, R12 + B runtime·callbackasm1(SB) + MOVW $622, R12 + B runtime·callbackasm1(SB) + MOVW $623, R12 + B runtime·callbackasm1(SB) + MOVW $624, R12 + B runtime·callbackasm1(SB) + MOVW $625, R12 + B runtime·callbackasm1(SB) + MOVW $626, R12 + B runtime·callbackasm1(SB) + MOVW $627, R12 + B runtime·callbackasm1(SB) + MOVW $628, R12 + B runtime·callbackasm1(SB) + MOVW $629, R12 + B runtime·callbackasm1(SB) + MOVW $630, R12 + B runtime·callbackasm1(SB) + MOVW $631, R12 + B runtime·callbackasm1(SB) + MOVW $632, R12 + B runtime·callbackasm1(SB) + MOVW $633, R12 + B runtime·callbackasm1(SB) + MOVW $634, R12 + B runtime·callbackasm1(SB) + MOVW $635, R12 + B runtime·callbackasm1(SB) + MOVW $636, R12 + B runtime·callbackasm1(SB) + MOVW $637, R12 + B runtime·callbackasm1(SB) + MOVW $638, R12 + B runtime·callbackasm1(SB) + MOVW $639, R12 + B runtime·callbackasm1(SB) + MOVW $640, R12 + B runtime·callbackasm1(SB) + MOVW $641, R12 + B runtime·callbackasm1(SB) + MOVW $642, R12 + B runtime·callbackasm1(SB) + MOVW $643, R12 + B runtime·callbackasm1(SB) + MOVW $644, R12 + B runtime·callbackasm1(SB) + MOVW $645, R12 + B runtime·callbackasm1(SB) + MOVW $646, R12 + B runtime·callbackasm1(SB) + MOVW $647, R12 + B runtime·callbackasm1(SB) + MOVW $648, R12 + B runtime·callbackasm1(SB) + MOVW $649, R12 + B runtime·callbackasm1(SB) + MOVW $650, R12 + B runtime·callbackasm1(SB) + MOVW $651, R12 + B runtime·callbackasm1(SB) + MOVW $652, R12 + B runtime·callbackasm1(SB) + MOVW $653, R12 + B runtime·callbackasm1(SB) + MOVW $654, R12 + B runtime·callbackasm1(SB) + MOVW $655, R12 + B runtime·callbackasm1(SB) + MOVW $656, R12 + B runtime·callbackasm1(SB) + MOVW $657, R12 + B runtime·callbackasm1(SB) + MOVW $658, R12 + B runtime·callbackasm1(SB) + MOVW $659, R12 + B runtime·callbackasm1(SB) + MOVW $660, R12 + B runtime·callbackasm1(SB) + MOVW $661, R12 + B runtime·callbackasm1(SB) + MOVW $662, R12 + B runtime·callbackasm1(SB) + MOVW $663, R12 + B runtime·callbackasm1(SB) + MOVW $664, R12 + B runtime·callbackasm1(SB) + MOVW $665, R12 + B runtime·callbackasm1(SB) + MOVW $666, R12 + B runtime·callbackasm1(SB) + MOVW $667, R12 + B runtime·callbackasm1(SB) + MOVW $668, R12 + B runtime·callbackasm1(SB) + MOVW $669, R12 + B runtime·callbackasm1(SB) + MOVW $670, R12 + B runtime·callbackasm1(SB) + MOVW $671, R12 + B runtime·callbackasm1(SB) + MOVW $672, R12 + B runtime·callbackasm1(SB) + MOVW $673, R12 + B runtime·callbackasm1(SB) + MOVW $674, R12 + B runtime·callbackasm1(SB) + MOVW $675, R12 + B runtime·callbackasm1(SB) + MOVW $676, R12 + B runtime·callbackasm1(SB) + MOVW $677, R12 + B runtime·callbackasm1(SB) + MOVW $678, R12 + B runtime·callbackasm1(SB) + MOVW $679, R12 + B runtime·callbackasm1(SB) + MOVW $680, R12 + B runtime·callbackasm1(SB) + MOVW $681, R12 + B runtime·callbackasm1(SB) + MOVW $682, R12 + B runtime·callbackasm1(SB) + MOVW $683, R12 + B runtime·callbackasm1(SB) + MOVW $684, R12 + B runtime·callbackasm1(SB) + MOVW $685, R12 + B runtime·callbackasm1(SB) + MOVW $686, R12 + B runtime·callbackasm1(SB) + MOVW $687, R12 + B runtime·callbackasm1(SB) + MOVW $688, R12 + B runtime·callbackasm1(SB) + MOVW $689, R12 + B runtime·callbackasm1(SB) + MOVW $690, R12 + B runtime·callbackasm1(SB) + MOVW $691, R12 + B runtime·callbackasm1(SB) + MOVW $692, R12 + B runtime·callbackasm1(SB) + MOVW $693, R12 + B runtime·callbackasm1(SB) + MOVW $694, R12 + B runtime·callbackasm1(SB) + MOVW $695, R12 + B runtime·callbackasm1(SB) + MOVW $696, R12 + B runtime·callbackasm1(SB) + MOVW $697, R12 + B runtime·callbackasm1(SB) + MOVW $698, R12 + B runtime·callbackasm1(SB) + MOVW $699, R12 + B runtime·callbackasm1(SB) + MOVW $700, R12 + B runtime·callbackasm1(SB) + MOVW $701, R12 + B runtime·callbackasm1(SB) + MOVW $702, R12 + B runtime·callbackasm1(SB) + MOVW $703, R12 + B runtime·callbackasm1(SB) + MOVW $704, R12 + B runtime·callbackasm1(SB) + MOVW $705, R12 + B runtime·callbackasm1(SB) + MOVW $706, R12 + B runtime·callbackasm1(SB) + MOVW $707, R12 + B runtime·callbackasm1(SB) + MOVW $708, R12 + B runtime·callbackasm1(SB) + MOVW $709, R12 + B runtime·callbackasm1(SB) + MOVW $710, R12 + B runtime·callbackasm1(SB) + MOVW $711, R12 + B runtime·callbackasm1(SB) + MOVW $712, R12 + B runtime·callbackasm1(SB) + MOVW $713, R12 + B runtime·callbackasm1(SB) + MOVW $714, R12 + B runtime·callbackasm1(SB) + MOVW $715, R12 + B runtime·callbackasm1(SB) + MOVW $716, R12 + B runtime·callbackasm1(SB) + MOVW $717, R12 + B runtime·callbackasm1(SB) + MOVW $718, R12 + B runtime·callbackasm1(SB) + MOVW $719, R12 + B runtime·callbackasm1(SB) + MOVW $720, R12 + B runtime·callbackasm1(SB) + MOVW $721, R12 + B runtime·callbackasm1(SB) + MOVW $722, R12 + B runtime·callbackasm1(SB) + MOVW $723, R12 + B runtime·callbackasm1(SB) + MOVW $724, R12 + B runtime·callbackasm1(SB) + MOVW $725, R12 + B runtime·callbackasm1(SB) + MOVW $726, R12 + B runtime·callbackasm1(SB) + MOVW $727, R12 + B runtime·callbackasm1(SB) + MOVW $728, R12 + B runtime·callbackasm1(SB) + MOVW $729, R12 + B runtime·callbackasm1(SB) + MOVW $730, R12 + B runtime·callbackasm1(SB) + MOVW $731, R12 + B runtime·callbackasm1(SB) + MOVW $732, R12 + B runtime·callbackasm1(SB) + MOVW $733, R12 + B runtime·callbackasm1(SB) + MOVW $734, R12 + B runtime·callbackasm1(SB) + MOVW $735, R12 + B runtime·callbackasm1(SB) + MOVW $736, R12 + B runtime·callbackasm1(SB) + MOVW $737, R12 + B runtime·callbackasm1(SB) + MOVW $738, R12 + B runtime·callbackasm1(SB) + MOVW $739, R12 + B runtime·callbackasm1(SB) + MOVW $740, R12 + B runtime·callbackasm1(SB) + MOVW $741, R12 + B runtime·callbackasm1(SB) + MOVW $742, R12 + B runtime·callbackasm1(SB) + MOVW $743, R12 + B runtime·callbackasm1(SB) + MOVW $744, R12 + B runtime·callbackasm1(SB) + MOVW $745, R12 + B runtime·callbackasm1(SB) + MOVW $746, R12 + B runtime·callbackasm1(SB) + MOVW $747, R12 + B runtime·callbackasm1(SB) + MOVW $748, R12 + B runtime·callbackasm1(SB) + MOVW $749, R12 + B runtime·callbackasm1(SB) + MOVW $750, R12 + B runtime·callbackasm1(SB) + MOVW $751, R12 + B runtime·callbackasm1(SB) + MOVW $752, R12 + B runtime·callbackasm1(SB) + MOVW $753, R12 + B runtime·callbackasm1(SB) + MOVW $754, R12 + B runtime·callbackasm1(SB) + MOVW $755, R12 + B runtime·callbackasm1(SB) + MOVW $756, R12 + B runtime·callbackasm1(SB) + MOVW $757, R12 + B runtime·callbackasm1(SB) + MOVW $758, R12 + B runtime·callbackasm1(SB) + MOVW $759, R12 + B runtime·callbackasm1(SB) + MOVW $760, R12 + B runtime·callbackasm1(SB) + MOVW $761, R12 + B runtime·callbackasm1(SB) + MOVW $762, R12 + B runtime·callbackasm1(SB) + MOVW $763, R12 + B runtime·callbackasm1(SB) + MOVW $764, R12 + B runtime·callbackasm1(SB) + MOVW $765, R12 + B runtime·callbackasm1(SB) + MOVW $766, R12 + B runtime·callbackasm1(SB) + MOVW $767, R12 + B runtime·callbackasm1(SB) + MOVW $768, R12 + B runtime·callbackasm1(SB) + MOVW $769, R12 + B runtime·callbackasm1(SB) + MOVW $770, R12 + B runtime·callbackasm1(SB) + MOVW $771, R12 + B runtime·callbackasm1(SB) + MOVW $772, R12 + B runtime·callbackasm1(SB) + MOVW $773, R12 + B runtime·callbackasm1(SB) + MOVW $774, R12 + B runtime·callbackasm1(SB) + MOVW $775, R12 + B runtime·callbackasm1(SB) + MOVW $776, R12 + B runtime·callbackasm1(SB) + MOVW $777, R12 + B runtime·callbackasm1(SB) + MOVW $778, R12 + B runtime·callbackasm1(SB) + MOVW $779, R12 + B runtime·callbackasm1(SB) + MOVW $780, R12 + B runtime·callbackasm1(SB) + MOVW $781, R12 + B runtime·callbackasm1(SB) + MOVW $782, R12 + B runtime·callbackasm1(SB) + MOVW $783, R12 + B runtime·callbackasm1(SB) + MOVW $784, R12 + B runtime·callbackasm1(SB) + MOVW $785, R12 + B runtime·callbackasm1(SB) + MOVW $786, R12 + B runtime·callbackasm1(SB) + MOVW $787, R12 + B runtime·callbackasm1(SB) + MOVW $788, R12 + B runtime·callbackasm1(SB) + MOVW $789, R12 + B runtime·callbackasm1(SB) + MOVW $790, R12 + B runtime·callbackasm1(SB) + MOVW $791, R12 + B runtime·callbackasm1(SB) + MOVW $792, R12 + B runtime·callbackasm1(SB) + MOVW $793, R12 + B runtime·callbackasm1(SB) + MOVW $794, R12 + B runtime·callbackasm1(SB) + MOVW $795, R12 + B runtime·callbackasm1(SB) + MOVW $796, R12 + B runtime·callbackasm1(SB) + MOVW $797, R12 + B runtime·callbackasm1(SB) + MOVW $798, R12 + B runtime·callbackasm1(SB) + MOVW $799, R12 + B runtime·callbackasm1(SB) + MOVW $800, R12 + B runtime·callbackasm1(SB) + MOVW $801, R12 + B runtime·callbackasm1(SB) + MOVW $802, R12 + B runtime·callbackasm1(SB) + MOVW $803, R12 + B runtime·callbackasm1(SB) + MOVW $804, R12 + B runtime·callbackasm1(SB) + MOVW $805, R12 + B runtime·callbackasm1(SB) + MOVW $806, R12 + B runtime·callbackasm1(SB) + MOVW $807, R12 + B runtime·callbackasm1(SB) + MOVW $808, R12 + B runtime·callbackasm1(SB) + MOVW $809, R12 + B runtime·callbackasm1(SB) + MOVW $810, R12 + B runtime·callbackasm1(SB) + MOVW $811, R12 + B runtime·callbackasm1(SB) + MOVW $812, R12 + B runtime·callbackasm1(SB) + MOVW $813, R12 + B runtime·callbackasm1(SB) + MOVW $814, R12 + B runtime·callbackasm1(SB) + MOVW $815, R12 + B runtime·callbackasm1(SB) + MOVW $816, R12 + B runtime·callbackasm1(SB) + MOVW $817, R12 + B runtime·callbackasm1(SB) + MOVW $818, R12 + B runtime·callbackasm1(SB) + MOVW $819, R12 + B runtime·callbackasm1(SB) + MOVW $820, R12 + B runtime·callbackasm1(SB) + MOVW $821, R12 + B runtime·callbackasm1(SB) + MOVW $822, R12 + B runtime·callbackasm1(SB) + MOVW $823, R12 + B runtime·callbackasm1(SB) + MOVW $824, R12 + B runtime·callbackasm1(SB) + MOVW $825, R12 + B runtime·callbackasm1(SB) + MOVW $826, R12 + B runtime·callbackasm1(SB) + MOVW $827, R12 + B runtime·callbackasm1(SB) + MOVW $828, R12 + B runtime·callbackasm1(SB) + MOVW $829, R12 + B runtime·callbackasm1(SB) + MOVW $830, R12 + B runtime·callbackasm1(SB) + MOVW $831, R12 + B runtime·callbackasm1(SB) + MOVW $832, R12 + B runtime·callbackasm1(SB) + MOVW $833, R12 + B runtime·callbackasm1(SB) + MOVW $834, R12 + B runtime·callbackasm1(SB) + MOVW $835, R12 + B runtime·callbackasm1(SB) + MOVW $836, R12 + B runtime·callbackasm1(SB) + MOVW $837, R12 + B runtime·callbackasm1(SB) + MOVW $838, R12 + B runtime·callbackasm1(SB) + MOVW $839, R12 + B runtime·callbackasm1(SB) + MOVW $840, R12 + B runtime·callbackasm1(SB) + MOVW $841, R12 + B runtime·callbackasm1(SB) + MOVW $842, R12 + B runtime·callbackasm1(SB) + MOVW $843, R12 + B runtime·callbackasm1(SB) + MOVW $844, R12 + B runtime·callbackasm1(SB) + MOVW $845, R12 + B runtime·callbackasm1(SB) + MOVW $846, R12 + B runtime·callbackasm1(SB) + MOVW $847, R12 + B runtime·callbackasm1(SB) + MOVW $848, R12 + B runtime·callbackasm1(SB) + MOVW $849, R12 + B runtime·callbackasm1(SB) + MOVW $850, R12 + B runtime·callbackasm1(SB) + MOVW $851, R12 + B runtime·callbackasm1(SB) + MOVW $852, R12 + B runtime·callbackasm1(SB) + MOVW $853, R12 + B runtime·callbackasm1(SB) + MOVW $854, R12 + B runtime·callbackasm1(SB) + MOVW $855, R12 + B runtime·callbackasm1(SB) + MOVW $856, R12 + B runtime·callbackasm1(SB) + MOVW $857, R12 + B runtime·callbackasm1(SB) + MOVW $858, R12 + B runtime·callbackasm1(SB) + MOVW $859, R12 + B runtime·callbackasm1(SB) + MOVW $860, R12 + B runtime·callbackasm1(SB) + MOVW $861, R12 + B runtime·callbackasm1(SB) + MOVW $862, R12 + B runtime·callbackasm1(SB) + MOVW $863, R12 + B runtime·callbackasm1(SB) + MOVW $864, R12 + B runtime·callbackasm1(SB) + MOVW $865, R12 + B runtime·callbackasm1(SB) + MOVW $866, R12 + B runtime·callbackasm1(SB) + MOVW $867, R12 + B runtime·callbackasm1(SB) + MOVW $868, R12 + B runtime·callbackasm1(SB) + MOVW $869, R12 + B runtime·callbackasm1(SB) + MOVW $870, R12 + B runtime·callbackasm1(SB) + MOVW $871, R12 + B runtime·callbackasm1(SB) + MOVW $872, R12 + B runtime·callbackasm1(SB) + MOVW $873, R12 + B runtime·callbackasm1(SB) + MOVW $874, R12 + B runtime·callbackasm1(SB) + MOVW $875, R12 + B runtime·callbackasm1(SB) + MOVW $876, R12 + B runtime·callbackasm1(SB) + MOVW $877, R12 + B runtime·callbackasm1(SB) + MOVW $878, R12 + B runtime·callbackasm1(SB) + MOVW $879, R12 + B runtime·callbackasm1(SB) + MOVW $880, R12 + B runtime·callbackasm1(SB) + MOVW $881, R12 + B runtime·callbackasm1(SB) + MOVW $882, R12 + B runtime·callbackasm1(SB) + MOVW $883, R12 + B runtime·callbackasm1(SB) + MOVW $884, R12 + B runtime·callbackasm1(SB) + MOVW $885, R12 + B runtime·callbackasm1(SB) + MOVW $886, R12 + B runtime·callbackasm1(SB) + MOVW $887, R12 + B runtime·callbackasm1(SB) + MOVW $888, R12 + B runtime·callbackasm1(SB) + MOVW $889, R12 + B runtime·callbackasm1(SB) + MOVW $890, R12 + B runtime·callbackasm1(SB) + MOVW $891, R12 + B runtime·callbackasm1(SB) + MOVW $892, R12 + B runtime·callbackasm1(SB) + MOVW $893, R12 + B runtime·callbackasm1(SB) + MOVW $894, R12 + B runtime·callbackasm1(SB) + MOVW $895, R12 + B runtime·callbackasm1(SB) + MOVW $896, R12 + B runtime·callbackasm1(SB) + MOVW $897, R12 + B runtime·callbackasm1(SB) + MOVW $898, R12 + B runtime·callbackasm1(SB) + MOVW $899, R12 + B runtime·callbackasm1(SB) + MOVW $900, R12 + B runtime·callbackasm1(SB) + MOVW $901, R12 + B runtime·callbackasm1(SB) + MOVW $902, R12 + B runtime·callbackasm1(SB) + MOVW $903, R12 + B runtime·callbackasm1(SB) + MOVW $904, R12 + B runtime·callbackasm1(SB) + MOVW $905, R12 + B runtime·callbackasm1(SB) + MOVW $906, R12 + B runtime·callbackasm1(SB) + MOVW $907, R12 + B runtime·callbackasm1(SB) + MOVW $908, R12 + B runtime·callbackasm1(SB) + MOVW $909, R12 + B runtime·callbackasm1(SB) + MOVW $910, R12 + B runtime·callbackasm1(SB) + MOVW $911, R12 + B runtime·callbackasm1(SB) + MOVW $912, R12 + B runtime·callbackasm1(SB) + MOVW $913, R12 + B runtime·callbackasm1(SB) + MOVW $914, R12 + B runtime·callbackasm1(SB) + MOVW $915, R12 + B runtime·callbackasm1(SB) + MOVW $916, R12 + B runtime·callbackasm1(SB) + MOVW $917, R12 + B runtime·callbackasm1(SB) + MOVW $918, R12 + B runtime·callbackasm1(SB) + MOVW $919, R12 + B runtime·callbackasm1(SB) + MOVW $920, R12 + B runtime·callbackasm1(SB) + MOVW $921, R12 + B runtime·callbackasm1(SB) + MOVW $922, R12 + B runtime·callbackasm1(SB) + MOVW $923, R12 + B runtime·callbackasm1(SB) + MOVW $924, R12 + B runtime·callbackasm1(SB) + MOVW $925, R12 + B runtime·callbackasm1(SB) + MOVW $926, R12 + B runtime·callbackasm1(SB) + MOVW $927, R12 + B runtime·callbackasm1(SB) + MOVW $928, R12 + B runtime·callbackasm1(SB) + MOVW $929, R12 + B runtime·callbackasm1(SB) + MOVW $930, R12 + B runtime·callbackasm1(SB) + MOVW $931, R12 + B runtime·callbackasm1(SB) + MOVW $932, R12 + B runtime·callbackasm1(SB) + MOVW $933, R12 + B runtime·callbackasm1(SB) + MOVW $934, R12 + B runtime·callbackasm1(SB) + MOVW $935, R12 + B runtime·callbackasm1(SB) + MOVW $936, R12 + B runtime·callbackasm1(SB) + MOVW $937, R12 + B runtime·callbackasm1(SB) + MOVW $938, R12 + B runtime·callbackasm1(SB) + MOVW $939, R12 + B runtime·callbackasm1(SB) + MOVW $940, R12 + B runtime·callbackasm1(SB) + MOVW $941, R12 + B runtime·callbackasm1(SB) + MOVW $942, R12 + B runtime·callbackasm1(SB) + MOVW $943, R12 + B runtime·callbackasm1(SB) + MOVW $944, R12 + B runtime·callbackasm1(SB) + MOVW $945, R12 + B runtime·callbackasm1(SB) + MOVW $946, R12 + B runtime·callbackasm1(SB) + MOVW $947, R12 + B runtime·callbackasm1(SB) + MOVW $948, R12 + B runtime·callbackasm1(SB) + MOVW $949, R12 + B runtime·callbackasm1(SB) + MOVW $950, R12 + B runtime·callbackasm1(SB) + MOVW $951, R12 + B runtime·callbackasm1(SB) + MOVW $952, R12 + B runtime·callbackasm1(SB) + MOVW $953, R12 + B runtime·callbackasm1(SB) + MOVW $954, R12 + B runtime·callbackasm1(SB) + MOVW $955, R12 + B runtime·callbackasm1(SB) + MOVW $956, R12 + B runtime·callbackasm1(SB) + MOVW $957, R12 + B runtime·callbackasm1(SB) + MOVW $958, R12 + B runtime·callbackasm1(SB) + MOVW $959, R12 + B runtime·callbackasm1(SB) + MOVW $960, R12 + B runtime·callbackasm1(SB) + MOVW $961, R12 + B runtime·callbackasm1(SB) + MOVW $962, R12 + B runtime·callbackasm1(SB) + MOVW $963, R12 + B runtime·callbackasm1(SB) + MOVW $964, R12 + B runtime·callbackasm1(SB) + MOVW $965, R12 + B runtime·callbackasm1(SB) + MOVW $966, R12 + B runtime·callbackasm1(SB) + MOVW $967, R12 + B runtime·callbackasm1(SB) + MOVW $968, R12 + B runtime·callbackasm1(SB) + MOVW $969, R12 + B runtime·callbackasm1(SB) + MOVW $970, R12 + B runtime·callbackasm1(SB) + MOVW $971, R12 + B runtime·callbackasm1(SB) + MOVW $972, R12 + B runtime·callbackasm1(SB) + MOVW $973, R12 + B runtime·callbackasm1(SB) + MOVW $974, R12 + B runtime·callbackasm1(SB) + MOVW $975, R12 + B runtime·callbackasm1(SB) + MOVW $976, R12 + B runtime·callbackasm1(SB) + MOVW $977, R12 + B runtime·callbackasm1(SB) + MOVW $978, R12 + B runtime·callbackasm1(SB) + MOVW $979, R12 + B runtime·callbackasm1(SB) + MOVW $980, R12 + B runtime·callbackasm1(SB) + MOVW $981, R12 + B runtime·callbackasm1(SB) + MOVW $982, R12 + B runtime·callbackasm1(SB) + MOVW $983, R12 + B runtime·callbackasm1(SB) + MOVW $984, R12 + B runtime·callbackasm1(SB) + MOVW $985, R12 + B runtime·callbackasm1(SB) + MOVW $986, R12 + B runtime·callbackasm1(SB) + MOVW $987, R12 + B runtime·callbackasm1(SB) + MOVW $988, R12 + B runtime·callbackasm1(SB) + MOVW $989, R12 + B runtime·callbackasm1(SB) + MOVW $990, R12 + B runtime·callbackasm1(SB) + MOVW $991, R12 + B runtime·callbackasm1(SB) + MOVW $992, R12 + B runtime·callbackasm1(SB) + MOVW $993, R12 + B runtime·callbackasm1(SB) + MOVW $994, R12 + B runtime·callbackasm1(SB) + MOVW $995, R12 + B runtime·callbackasm1(SB) + MOVW $996, R12 + B runtime·callbackasm1(SB) + MOVW $997, R12 + B runtime·callbackasm1(SB) + MOVW $998, R12 + B runtime·callbackasm1(SB) + MOVW $999, R12 + B runtime·callbackasm1(SB) + MOVW $1000, R12 + B runtime·callbackasm1(SB) + MOVW $1001, R12 + B runtime·callbackasm1(SB) + MOVW $1002, R12 + B runtime·callbackasm1(SB) + MOVW $1003, R12 + B runtime·callbackasm1(SB) + MOVW $1004, R12 + B runtime·callbackasm1(SB) + MOVW $1005, R12 + B runtime·callbackasm1(SB) + MOVW $1006, R12 + B runtime·callbackasm1(SB) + MOVW $1007, R12 + B runtime·callbackasm1(SB) + MOVW $1008, R12 + B runtime·callbackasm1(SB) + MOVW $1009, R12 + B runtime·callbackasm1(SB) + MOVW $1010, R12 + B runtime·callbackasm1(SB) + MOVW $1011, R12 + B runtime·callbackasm1(SB) + MOVW $1012, R12 + B runtime·callbackasm1(SB) + MOVW $1013, R12 + B runtime·callbackasm1(SB) + MOVW $1014, R12 + B runtime·callbackasm1(SB) + MOVW $1015, R12 + B runtime·callbackasm1(SB) + MOVW $1016, R12 + B runtime·callbackasm1(SB) + MOVW $1017, R12 + B runtime·callbackasm1(SB) + MOVW $1018, R12 + B runtime·callbackasm1(SB) + MOVW $1019, R12 + B runtime·callbackasm1(SB) + MOVW $1020, R12 + B runtime·callbackasm1(SB) + MOVW $1021, R12 + B runtime·callbackasm1(SB) + MOVW $1022, R12 + B runtime·callbackasm1(SB) + MOVW $1023, R12 + B runtime·callbackasm1(SB) + MOVW $1024, R12 + B runtime·callbackasm1(SB) + MOVW $1025, R12 + B runtime·callbackasm1(SB) + MOVW $1026, R12 + B runtime·callbackasm1(SB) + MOVW $1027, R12 + B runtime·callbackasm1(SB) + MOVW $1028, R12 + B runtime·callbackasm1(SB) + MOVW $1029, R12 + B runtime·callbackasm1(SB) + MOVW $1030, R12 + B runtime·callbackasm1(SB) + MOVW $1031, R12 + B runtime·callbackasm1(SB) + MOVW $1032, R12 + B runtime·callbackasm1(SB) + MOVW $1033, R12 + B runtime·callbackasm1(SB) + MOVW $1034, R12 + B runtime·callbackasm1(SB) + MOVW $1035, R12 + B runtime·callbackasm1(SB) + MOVW $1036, R12 + B runtime·callbackasm1(SB) + MOVW $1037, R12 + B runtime·callbackasm1(SB) + MOVW $1038, R12 + B runtime·callbackasm1(SB) + MOVW $1039, R12 + B runtime·callbackasm1(SB) + MOVW $1040, R12 + B runtime·callbackasm1(SB) + MOVW $1041, R12 + B runtime·callbackasm1(SB) + MOVW $1042, R12 + B runtime·callbackasm1(SB) + MOVW $1043, R12 + B runtime·callbackasm1(SB) + MOVW $1044, R12 + B runtime·callbackasm1(SB) + MOVW $1045, R12 + B runtime·callbackasm1(SB) + MOVW $1046, R12 + B runtime·callbackasm1(SB) + MOVW $1047, R12 + B runtime·callbackasm1(SB) + MOVW $1048, R12 + B runtime·callbackasm1(SB) + MOVW $1049, R12 + B runtime·callbackasm1(SB) + MOVW $1050, R12 + B runtime·callbackasm1(SB) + MOVW $1051, R12 + B runtime·callbackasm1(SB) + MOVW $1052, R12 + B runtime·callbackasm1(SB) + MOVW $1053, R12 + B runtime·callbackasm1(SB) + MOVW $1054, R12 + B runtime·callbackasm1(SB) + MOVW $1055, R12 + B runtime·callbackasm1(SB) + MOVW $1056, R12 + B runtime·callbackasm1(SB) + MOVW $1057, R12 + B runtime·callbackasm1(SB) + MOVW $1058, R12 + B runtime·callbackasm1(SB) + MOVW $1059, R12 + B runtime·callbackasm1(SB) + MOVW $1060, R12 + B runtime·callbackasm1(SB) + MOVW $1061, R12 + B runtime·callbackasm1(SB) + MOVW $1062, R12 + B runtime·callbackasm1(SB) + MOVW $1063, R12 + B runtime·callbackasm1(SB) + MOVW $1064, R12 + B runtime·callbackasm1(SB) + MOVW $1065, R12 + B runtime·callbackasm1(SB) + MOVW $1066, R12 + B runtime·callbackasm1(SB) + MOVW $1067, R12 + B runtime·callbackasm1(SB) + MOVW $1068, R12 + B runtime·callbackasm1(SB) + MOVW $1069, R12 + B runtime·callbackasm1(SB) + MOVW $1070, R12 + B runtime·callbackasm1(SB) + MOVW $1071, R12 + B runtime·callbackasm1(SB) + MOVW $1072, R12 + B runtime·callbackasm1(SB) + MOVW $1073, R12 + B runtime·callbackasm1(SB) + MOVW $1074, R12 + B runtime·callbackasm1(SB) + MOVW $1075, R12 + B runtime·callbackasm1(SB) + MOVW $1076, R12 + B runtime·callbackasm1(SB) + MOVW $1077, R12 + B runtime·callbackasm1(SB) + MOVW $1078, R12 + B runtime·callbackasm1(SB) + MOVW $1079, R12 + B runtime·callbackasm1(SB) + MOVW $1080, R12 + B runtime·callbackasm1(SB) + MOVW $1081, R12 + B runtime·callbackasm1(SB) + MOVW $1082, R12 + B runtime·callbackasm1(SB) + MOVW $1083, R12 + B runtime·callbackasm1(SB) + MOVW $1084, R12 + B runtime·callbackasm1(SB) + MOVW $1085, R12 + B runtime·callbackasm1(SB) + MOVW $1086, R12 + B runtime·callbackasm1(SB) + MOVW $1087, R12 + B runtime·callbackasm1(SB) + MOVW $1088, R12 + B runtime·callbackasm1(SB) + MOVW $1089, R12 + B runtime·callbackasm1(SB) + MOVW $1090, R12 + B runtime·callbackasm1(SB) + MOVW $1091, R12 + B runtime·callbackasm1(SB) + MOVW $1092, R12 + B runtime·callbackasm1(SB) + MOVW $1093, R12 + B runtime·callbackasm1(SB) + MOVW $1094, R12 + B runtime·callbackasm1(SB) + MOVW $1095, R12 + B runtime·callbackasm1(SB) + MOVW $1096, R12 + B runtime·callbackasm1(SB) + MOVW $1097, R12 + B runtime·callbackasm1(SB) + MOVW $1098, R12 + B runtime·callbackasm1(SB) + MOVW $1099, R12 + B runtime·callbackasm1(SB) + MOVW $1100, R12 + B runtime·callbackasm1(SB) + MOVW $1101, R12 + B runtime·callbackasm1(SB) + MOVW $1102, R12 + B runtime·callbackasm1(SB) + MOVW $1103, R12 + B runtime·callbackasm1(SB) + MOVW $1104, R12 + B runtime·callbackasm1(SB) + MOVW $1105, R12 + B runtime·callbackasm1(SB) + MOVW $1106, R12 + B runtime·callbackasm1(SB) + MOVW $1107, R12 + B runtime·callbackasm1(SB) + MOVW $1108, R12 + B runtime·callbackasm1(SB) + MOVW $1109, R12 + B runtime·callbackasm1(SB) + MOVW $1110, R12 + B runtime·callbackasm1(SB) + MOVW $1111, R12 + B runtime·callbackasm1(SB) + MOVW $1112, R12 + B runtime·callbackasm1(SB) + MOVW $1113, R12 + B runtime·callbackasm1(SB) + MOVW $1114, R12 + B runtime·callbackasm1(SB) + MOVW $1115, R12 + B runtime·callbackasm1(SB) + MOVW $1116, R12 + B runtime·callbackasm1(SB) + MOVW $1117, R12 + B runtime·callbackasm1(SB) + MOVW $1118, R12 + B runtime·callbackasm1(SB) + MOVW $1119, R12 + B runtime·callbackasm1(SB) + MOVW $1120, R12 + B runtime·callbackasm1(SB) + MOVW $1121, R12 + B runtime·callbackasm1(SB) + MOVW $1122, R12 + B runtime·callbackasm1(SB) + MOVW $1123, R12 + B runtime·callbackasm1(SB) + MOVW $1124, R12 + B runtime·callbackasm1(SB) + MOVW $1125, R12 + B runtime·callbackasm1(SB) + MOVW $1126, R12 + B runtime·callbackasm1(SB) + MOVW $1127, R12 + B runtime·callbackasm1(SB) + MOVW $1128, R12 + B runtime·callbackasm1(SB) + MOVW $1129, R12 + B runtime·callbackasm1(SB) + MOVW $1130, R12 + B runtime·callbackasm1(SB) + MOVW $1131, R12 + B runtime·callbackasm1(SB) + MOVW $1132, R12 + B runtime·callbackasm1(SB) + MOVW $1133, R12 + B runtime·callbackasm1(SB) + MOVW $1134, R12 + B runtime·callbackasm1(SB) + MOVW $1135, R12 + B runtime·callbackasm1(SB) + MOVW $1136, R12 + B runtime·callbackasm1(SB) + MOVW $1137, R12 + B runtime·callbackasm1(SB) + MOVW $1138, R12 + B runtime·callbackasm1(SB) + MOVW $1139, R12 + B runtime·callbackasm1(SB) + MOVW $1140, R12 + B runtime·callbackasm1(SB) + MOVW $1141, R12 + B runtime·callbackasm1(SB) + MOVW $1142, R12 + B runtime·callbackasm1(SB) + MOVW $1143, R12 + B runtime·callbackasm1(SB) + MOVW $1144, R12 + B runtime·callbackasm1(SB) + MOVW $1145, R12 + B runtime·callbackasm1(SB) + MOVW $1146, R12 + B runtime·callbackasm1(SB) + MOVW $1147, R12 + B runtime·callbackasm1(SB) + MOVW $1148, R12 + B runtime·callbackasm1(SB) + MOVW $1149, R12 + B runtime·callbackasm1(SB) + MOVW $1150, R12 + B runtime·callbackasm1(SB) + MOVW $1151, R12 + B runtime·callbackasm1(SB) + MOVW $1152, R12 + B runtime·callbackasm1(SB) + MOVW $1153, R12 + B runtime·callbackasm1(SB) + MOVW $1154, R12 + B runtime·callbackasm1(SB) + MOVW $1155, R12 + B runtime·callbackasm1(SB) + MOVW $1156, R12 + B runtime·callbackasm1(SB) + MOVW $1157, R12 + B runtime·callbackasm1(SB) + MOVW $1158, R12 + B runtime·callbackasm1(SB) + MOVW $1159, R12 + B runtime·callbackasm1(SB) + MOVW $1160, R12 + B runtime·callbackasm1(SB) + MOVW $1161, R12 + B runtime·callbackasm1(SB) + MOVW $1162, R12 + B runtime·callbackasm1(SB) + MOVW $1163, R12 + B runtime·callbackasm1(SB) + MOVW $1164, R12 + B runtime·callbackasm1(SB) + MOVW $1165, R12 + B runtime·callbackasm1(SB) + MOVW $1166, R12 + B runtime·callbackasm1(SB) + MOVW $1167, R12 + B runtime·callbackasm1(SB) + MOVW $1168, R12 + B runtime·callbackasm1(SB) + MOVW $1169, R12 + B runtime·callbackasm1(SB) + MOVW $1170, R12 + B runtime·callbackasm1(SB) + MOVW $1171, R12 + B runtime·callbackasm1(SB) + MOVW $1172, R12 + B runtime·callbackasm1(SB) + MOVW $1173, R12 + B runtime·callbackasm1(SB) + MOVW $1174, R12 + B runtime·callbackasm1(SB) + MOVW $1175, R12 + B runtime·callbackasm1(SB) + MOVW $1176, R12 + B runtime·callbackasm1(SB) + MOVW $1177, R12 + B runtime·callbackasm1(SB) + MOVW $1178, R12 + B runtime·callbackasm1(SB) + MOVW $1179, R12 + B runtime·callbackasm1(SB) + MOVW $1180, R12 + B runtime·callbackasm1(SB) + MOVW $1181, R12 + B runtime·callbackasm1(SB) + MOVW $1182, R12 + B runtime·callbackasm1(SB) + MOVW $1183, R12 + B runtime·callbackasm1(SB) + MOVW $1184, R12 + B runtime·callbackasm1(SB) + MOVW $1185, R12 + B runtime·callbackasm1(SB) + MOVW $1186, R12 + B runtime·callbackasm1(SB) + MOVW $1187, R12 + B runtime·callbackasm1(SB) + MOVW $1188, R12 + B runtime·callbackasm1(SB) + MOVW $1189, R12 + B runtime·callbackasm1(SB) + MOVW $1190, R12 + B runtime·callbackasm1(SB) + MOVW $1191, R12 + B runtime·callbackasm1(SB) + MOVW $1192, R12 + B runtime·callbackasm1(SB) + MOVW $1193, R12 + B runtime·callbackasm1(SB) + MOVW $1194, R12 + B runtime·callbackasm1(SB) + MOVW $1195, R12 + B runtime·callbackasm1(SB) + MOVW $1196, R12 + B runtime·callbackasm1(SB) + MOVW $1197, R12 + B runtime·callbackasm1(SB) + MOVW $1198, R12 + B runtime·callbackasm1(SB) + MOVW $1199, R12 + B runtime·callbackasm1(SB) + MOVW $1200, R12 + B runtime·callbackasm1(SB) + MOVW $1201, R12 + B runtime·callbackasm1(SB) + MOVW $1202, R12 + B runtime·callbackasm1(SB) + MOVW $1203, R12 + B runtime·callbackasm1(SB) + MOVW $1204, R12 + B runtime·callbackasm1(SB) + MOVW $1205, R12 + B runtime·callbackasm1(SB) + MOVW $1206, R12 + B runtime·callbackasm1(SB) + MOVW $1207, R12 + B runtime·callbackasm1(SB) + MOVW $1208, R12 + B runtime·callbackasm1(SB) + MOVW $1209, R12 + B runtime·callbackasm1(SB) + MOVW $1210, R12 + B runtime·callbackasm1(SB) + MOVW $1211, R12 + B runtime·callbackasm1(SB) + MOVW $1212, R12 + B runtime·callbackasm1(SB) + MOVW $1213, R12 + B runtime·callbackasm1(SB) + MOVW $1214, R12 + B runtime·callbackasm1(SB) + MOVW $1215, R12 + B runtime·callbackasm1(SB) + MOVW $1216, R12 + B runtime·callbackasm1(SB) + MOVW $1217, R12 + B runtime·callbackasm1(SB) + MOVW $1218, R12 + B runtime·callbackasm1(SB) + MOVW $1219, R12 + B runtime·callbackasm1(SB) + MOVW $1220, R12 + B runtime·callbackasm1(SB) + MOVW $1221, R12 + B runtime·callbackasm1(SB) + MOVW $1222, R12 + B runtime·callbackasm1(SB) + MOVW $1223, R12 + B runtime·callbackasm1(SB) + MOVW $1224, R12 + B runtime·callbackasm1(SB) + MOVW $1225, R12 + B runtime·callbackasm1(SB) + MOVW $1226, R12 + B runtime·callbackasm1(SB) + MOVW $1227, R12 + B runtime·callbackasm1(SB) + MOVW $1228, R12 + B runtime·callbackasm1(SB) + MOVW $1229, R12 + B runtime·callbackasm1(SB) + MOVW $1230, R12 + B runtime·callbackasm1(SB) + MOVW $1231, R12 + B runtime·callbackasm1(SB) + MOVW $1232, R12 + B runtime·callbackasm1(SB) + MOVW $1233, R12 + B runtime·callbackasm1(SB) + MOVW $1234, R12 + B runtime·callbackasm1(SB) + MOVW $1235, R12 + B runtime·callbackasm1(SB) + MOVW $1236, R12 + B runtime·callbackasm1(SB) + MOVW $1237, R12 + B runtime·callbackasm1(SB) + MOVW $1238, R12 + B runtime·callbackasm1(SB) + MOVW $1239, R12 + B runtime·callbackasm1(SB) + MOVW $1240, R12 + B runtime·callbackasm1(SB) + MOVW $1241, R12 + B runtime·callbackasm1(SB) + MOVW $1242, R12 + B runtime·callbackasm1(SB) + MOVW $1243, R12 + B runtime·callbackasm1(SB) + MOVW $1244, R12 + B runtime·callbackasm1(SB) + MOVW $1245, R12 + B runtime·callbackasm1(SB) + MOVW $1246, R12 + B runtime·callbackasm1(SB) + MOVW $1247, R12 + B runtime·callbackasm1(SB) + MOVW $1248, R12 + B runtime·callbackasm1(SB) + MOVW $1249, R12 + B runtime·callbackasm1(SB) + MOVW $1250, R12 + B runtime·callbackasm1(SB) + MOVW $1251, R12 + B runtime·callbackasm1(SB) + MOVW $1252, R12 + B runtime·callbackasm1(SB) + MOVW $1253, R12 + B runtime·callbackasm1(SB) + MOVW $1254, R12 + B runtime·callbackasm1(SB) + MOVW $1255, R12 + B runtime·callbackasm1(SB) + MOVW $1256, R12 + B runtime·callbackasm1(SB) + MOVW $1257, R12 + B runtime·callbackasm1(SB) + MOVW $1258, R12 + B runtime·callbackasm1(SB) + MOVW $1259, R12 + B runtime·callbackasm1(SB) + MOVW $1260, R12 + B runtime·callbackasm1(SB) + MOVW $1261, R12 + B runtime·callbackasm1(SB) + MOVW $1262, R12 + B runtime·callbackasm1(SB) + MOVW $1263, R12 + B runtime·callbackasm1(SB) + MOVW $1264, R12 + B runtime·callbackasm1(SB) + MOVW $1265, R12 + B runtime·callbackasm1(SB) + MOVW $1266, R12 + B runtime·callbackasm1(SB) + MOVW $1267, R12 + B runtime·callbackasm1(SB) + MOVW $1268, R12 + B runtime·callbackasm1(SB) + MOVW $1269, R12 + B runtime·callbackasm1(SB) + MOVW $1270, R12 + B runtime·callbackasm1(SB) + MOVW $1271, R12 + B runtime·callbackasm1(SB) + MOVW $1272, R12 + B runtime·callbackasm1(SB) + MOVW $1273, R12 + B runtime·callbackasm1(SB) + MOVW $1274, R12 + B runtime·callbackasm1(SB) + MOVW $1275, R12 + B runtime·callbackasm1(SB) + MOVW $1276, R12 + B runtime·callbackasm1(SB) + MOVW $1277, R12 + B runtime·callbackasm1(SB) + MOVW $1278, R12 + B runtime·callbackasm1(SB) + MOVW $1279, R12 + B runtime·callbackasm1(SB) + MOVW $1280, R12 + B runtime·callbackasm1(SB) + MOVW $1281, R12 + B runtime·callbackasm1(SB) + MOVW $1282, R12 + B runtime·callbackasm1(SB) + MOVW $1283, R12 + B runtime·callbackasm1(SB) + MOVW $1284, R12 + B runtime·callbackasm1(SB) + MOVW $1285, R12 + B runtime·callbackasm1(SB) + MOVW $1286, R12 + B runtime·callbackasm1(SB) + MOVW $1287, R12 + B runtime·callbackasm1(SB) + MOVW $1288, R12 + B runtime·callbackasm1(SB) + MOVW $1289, R12 + B runtime·callbackasm1(SB) + MOVW $1290, R12 + B runtime·callbackasm1(SB) + MOVW $1291, R12 + B runtime·callbackasm1(SB) + MOVW $1292, R12 + B runtime·callbackasm1(SB) + MOVW $1293, R12 + B runtime·callbackasm1(SB) + MOVW $1294, R12 + B runtime·callbackasm1(SB) + MOVW $1295, R12 + B runtime·callbackasm1(SB) + MOVW $1296, R12 + B runtime·callbackasm1(SB) + MOVW $1297, R12 + B runtime·callbackasm1(SB) + MOVW $1298, R12 + B runtime·callbackasm1(SB) + MOVW $1299, R12 + B runtime·callbackasm1(SB) + MOVW $1300, R12 + B runtime·callbackasm1(SB) + MOVW $1301, R12 + B runtime·callbackasm1(SB) + MOVW $1302, R12 + B runtime·callbackasm1(SB) + MOVW $1303, R12 + B runtime·callbackasm1(SB) + MOVW $1304, R12 + B runtime·callbackasm1(SB) + MOVW $1305, R12 + B runtime·callbackasm1(SB) + MOVW $1306, R12 + B runtime·callbackasm1(SB) + MOVW $1307, R12 + B runtime·callbackasm1(SB) + MOVW $1308, R12 + B runtime·callbackasm1(SB) + MOVW $1309, R12 + B runtime·callbackasm1(SB) + MOVW $1310, R12 + B runtime·callbackasm1(SB) + MOVW $1311, R12 + B runtime·callbackasm1(SB) + MOVW $1312, R12 + B runtime·callbackasm1(SB) + MOVW $1313, R12 + B runtime·callbackasm1(SB) + MOVW $1314, R12 + B runtime·callbackasm1(SB) + MOVW $1315, R12 + B runtime·callbackasm1(SB) + MOVW $1316, R12 + B runtime·callbackasm1(SB) + MOVW $1317, R12 + B runtime·callbackasm1(SB) + MOVW $1318, R12 + B runtime·callbackasm1(SB) + MOVW $1319, R12 + B runtime·callbackasm1(SB) + MOVW $1320, R12 + B runtime·callbackasm1(SB) + MOVW $1321, R12 + B runtime·callbackasm1(SB) + MOVW $1322, R12 + B runtime·callbackasm1(SB) + MOVW $1323, R12 + B runtime·callbackasm1(SB) + MOVW $1324, R12 + B runtime·callbackasm1(SB) + MOVW $1325, R12 + B runtime·callbackasm1(SB) + MOVW $1326, R12 + B runtime·callbackasm1(SB) + MOVW $1327, R12 + B runtime·callbackasm1(SB) + MOVW $1328, R12 + B runtime·callbackasm1(SB) + MOVW $1329, R12 + B runtime·callbackasm1(SB) + MOVW $1330, R12 + B runtime·callbackasm1(SB) + MOVW $1331, R12 + B runtime·callbackasm1(SB) + MOVW $1332, R12 + B runtime·callbackasm1(SB) + MOVW $1333, R12 + B runtime·callbackasm1(SB) + MOVW $1334, R12 + B runtime·callbackasm1(SB) + MOVW $1335, R12 + B runtime·callbackasm1(SB) + MOVW $1336, R12 + B runtime·callbackasm1(SB) + MOVW $1337, R12 + B runtime·callbackasm1(SB) + MOVW $1338, R12 + B runtime·callbackasm1(SB) + MOVW $1339, R12 + B runtime·callbackasm1(SB) + MOVW $1340, R12 + B runtime·callbackasm1(SB) + MOVW $1341, R12 + B runtime·callbackasm1(SB) + MOVW $1342, R12 + B runtime·callbackasm1(SB) + MOVW $1343, R12 + B runtime·callbackasm1(SB) + MOVW $1344, R12 + B runtime·callbackasm1(SB) + MOVW $1345, R12 + B runtime·callbackasm1(SB) + MOVW $1346, R12 + B runtime·callbackasm1(SB) + MOVW $1347, R12 + B runtime·callbackasm1(SB) + MOVW $1348, R12 + B runtime·callbackasm1(SB) + MOVW $1349, R12 + B runtime·callbackasm1(SB) + MOVW $1350, R12 + B runtime·callbackasm1(SB) + MOVW $1351, R12 + B runtime·callbackasm1(SB) + MOVW $1352, R12 + B runtime·callbackasm1(SB) + MOVW $1353, R12 + B runtime·callbackasm1(SB) + MOVW $1354, R12 + B runtime·callbackasm1(SB) + MOVW $1355, R12 + B runtime·callbackasm1(SB) + MOVW $1356, R12 + B runtime·callbackasm1(SB) + MOVW $1357, R12 + B runtime·callbackasm1(SB) + MOVW $1358, R12 + B runtime·callbackasm1(SB) + MOVW $1359, R12 + B runtime·callbackasm1(SB) + MOVW $1360, R12 + B runtime·callbackasm1(SB) + MOVW $1361, R12 + B runtime·callbackasm1(SB) + MOVW $1362, R12 + B runtime·callbackasm1(SB) + MOVW $1363, R12 + B runtime·callbackasm1(SB) + MOVW $1364, R12 + B runtime·callbackasm1(SB) + MOVW $1365, R12 + B runtime·callbackasm1(SB) + MOVW $1366, R12 + B runtime·callbackasm1(SB) + MOVW $1367, R12 + B runtime·callbackasm1(SB) + MOVW $1368, R12 + B runtime·callbackasm1(SB) + MOVW $1369, R12 + B runtime·callbackasm1(SB) + MOVW $1370, R12 + B runtime·callbackasm1(SB) + MOVW $1371, R12 + B runtime·callbackasm1(SB) + MOVW $1372, R12 + B runtime·callbackasm1(SB) + MOVW $1373, R12 + B runtime·callbackasm1(SB) + MOVW $1374, R12 + B runtime·callbackasm1(SB) + MOVW $1375, R12 + B runtime·callbackasm1(SB) + MOVW $1376, R12 + B runtime·callbackasm1(SB) + MOVW $1377, R12 + B runtime·callbackasm1(SB) + MOVW $1378, R12 + B runtime·callbackasm1(SB) + MOVW $1379, R12 + B runtime·callbackasm1(SB) + MOVW $1380, R12 + B runtime·callbackasm1(SB) + MOVW $1381, R12 + B runtime·callbackasm1(SB) + MOVW $1382, R12 + B runtime·callbackasm1(SB) + MOVW $1383, R12 + B runtime·callbackasm1(SB) + MOVW $1384, R12 + B runtime·callbackasm1(SB) + MOVW $1385, R12 + B runtime·callbackasm1(SB) + MOVW $1386, R12 + B runtime·callbackasm1(SB) + MOVW $1387, R12 + B runtime·callbackasm1(SB) + MOVW $1388, R12 + B runtime·callbackasm1(SB) + MOVW $1389, R12 + B runtime·callbackasm1(SB) + MOVW $1390, R12 + B runtime·callbackasm1(SB) + MOVW $1391, R12 + B runtime·callbackasm1(SB) + MOVW $1392, R12 + B runtime·callbackasm1(SB) + MOVW $1393, R12 + B runtime·callbackasm1(SB) + MOVW $1394, R12 + B runtime·callbackasm1(SB) + MOVW $1395, R12 + B runtime·callbackasm1(SB) + MOVW $1396, R12 + B runtime·callbackasm1(SB) + MOVW $1397, R12 + B runtime·callbackasm1(SB) + MOVW $1398, R12 + B runtime·callbackasm1(SB) + MOVW $1399, R12 + B runtime·callbackasm1(SB) + MOVW $1400, R12 + B runtime·callbackasm1(SB) + MOVW $1401, R12 + B runtime·callbackasm1(SB) + MOVW $1402, R12 + B runtime·callbackasm1(SB) + MOVW $1403, R12 + B runtime·callbackasm1(SB) + MOVW $1404, R12 + B runtime·callbackasm1(SB) + MOVW $1405, R12 + B runtime·callbackasm1(SB) + MOVW $1406, R12 + B runtime·callbackasm1(SB) + MOVW $1407, R12 + B runtime·callbackasm1(SB) + MOVW $1408, R12 + B runtime·callbackasm1(SB) + MOVW $1409, R12 + B runtime·callbackasm1(SB) + MOVW $1410, R12 + B runtime·callbackasm1(SB) + MOVW $1411, R12 + B runtime·callbackasm1(SB) + MOVW $1412, R12 + B runtime·callbackasm1(SB) + MOVW $1413, R12 + B runtime·callbackasm1(SB) + MOVW $1414, R12 + B runtime·callbackasm1(SB) + MOVW $1415, R12 + B runtime·callbackasm1(SB) + MOVW $1416, R12 + B runtime·callbackasm1(SB) + MOVW $1417, R12 + B runtime·callbackasm1(SB) + MOVW $1418, R12 + B runtime·callbackasm1(SB) + MOVW $1419, R12 + B runtime·callbackasm1(SB) + MOVW $1420, R12 + B runtime·callbackasm1(SB) + MOVW $1421, R12 + B runtime·callbackasm1(SB) + MOVW $1422, R12 + B runtime·callbackasm1(SB) + MOVW $1423, R12 + B runtime·callbackasm1(SB) + MOVW $1424, R12 + B runtime·callbackasm1(SB) + MOVW $1425, R12 + B runtime·callbackasm1(SB) + MOVW $1426, R12 + B runtime·callbackasm1(SB) + MOVW $1427, R12 + B runtime·callbackasm1(SB) + MOVW $1428, R12 + B runtime·callbackasm1(SB) + MOVW $1429, R12 + B runtime·callbackasm1(SB) + MOVW $1430, R12 + B runtime·callbackasm1(SB) + MOVW $1431, R12 + B runtime·callbackasm1(SB) + MOVW $1432, R12 + B runtime·callbackasm1(SB) + MOVW $1433, R12 + B runtime·callbackasm1(SB) + MOVW $1434, R12 + B runtime·callbackasm1(SB) + MOVW $1435, R12 + B runtime·callbackasm1(SB) + MOVW $1436, R12 + B runtime·callbackasm1(SB) + MOVW $1437, R12 + B runtime·callbackasm1(SB) + MOVW $1438, R12 + B runtime·callbackasm1(SB) + MOVW $1439, R12 + B runtime·callbackasm1(SB) + MOVW $1440, R12 + B runtime·callbackasm1(SB) + MOVW $1441, R12 + B runtime·callbackasm1(SB) + MOVW $1442, R12 + B runtime·callbackasm1(SB) + MOVW $1443, R12 + B runtime·callbackasm1(SB) + MOVW $1444, R12 + B runtime·callbackasm1(SB) + MOVW $1445, R12 + B runtime·callbackasm1(SB) + MOVW $1446, R12 + B runtime·callbackasm1(SB) + MOVW $1447, R12 + B runtime·callbackasm1(SB) + MOVW $1448, R12 + B runtime·callbackasm1(SB) + MOVW $1449, R12 + B runtime·callbackasm1(SB) + MOVW $1450, R12 + B runtime·callbackasm1(SB) + MOVW $1451, R12 + B runtime·callbackasm1(SB) + MOVW $1452, R12 + B runtime·callbackasm1(SB) + MOVW $1453, R12 + B runtime·callbackasm1(SB) + MOVW $1454, R12 + B runtime·callbackasm1(SB) + MOVW $1455, R12 + B runtime·callbackasm1(SB) + MOVW $1456, R12 + B runtime·callbackasm1(SB) + MOVW $1457, R12 + B runtime·callbackasm1(SB) + MOVW $1458, R12 + B runtime·callbackasm1(SB) + MOVW $1459, R12 + B runtime·callbackasm1(SB) + MOVW $1460, R12 + B runtime·callbackasm1(SB) + MOVW $1461, R12 + B runtime·callbackasm1(SB) + MOVW $1462, R12 + B runtime·callbackasm1(SB) + MOVW $1463, R12 + B runtime·callbackasm1(SB) + MOVW $1464, R12 + B runtime·callbackasm1(SB) + MOVW $1465, R12 + B runtime·callbackasm1(SB) + MOVW $1466, R12 + B runtime·callbackasm1(SB) + MOVW $1467, R12 + B runtime·callbackasm1(SB) + MOVW $1468, R12 + B runtime·callbackasm1(SB) + MOVW $1469, R12 + B runtime·callbackasm1(SB) + MOVW $1470, R12 + B runtime·callbackasm1(SB) + MOVW $1471, R12 + B runtime·callbackasm1(SB) + MOVW $1472, R12 + B runtime·callbackasm1(SB) + MOVW $1473, R12 + B runtime·callbackasm1(SB) + MOVW $1474, R12 + B runtime·callbackasm1(SB) + MOVW $1475, R12 + B runtime·callbackasm1(SB) + MOVW $1476, R12 + B runtime·callbackasm1(SB) + MOVW $1477, R12 + B runtime·callbackasm1(SB) + MOVW $1478, R12 + B runtime·callbackasm1(SB) + MOVW $1479, R12 + B runtime·callbackasm1(SB) + MOVW $1480, R12 + B runtime·callbackasm1(SB) + MOVW $1481, R12 + B runtime·callbackasm1(SB) + MOVW $1482, R12 + B runtime·callbackasm1(SB) + MOVW $1483, R12 + B runtime·callbackasm1(SB) + MOVW $1484, R12 + B runtime·callbackasm1(SB) + MOVW $1485, R12 + B runtime·callbackasm1(SB) + MOVW $1486, R12 + B runtime·callbackasm1(SB) + MOVW $1487, R12 + B runtime·callbackasm1(SB) + MOVW $1488, R12 + B runtime·callbackasm1(SB) + MOVW $1489, R12 + B runtime·callbackasm1(SB) + MOVW $1490, R12 + B runtime·callbackasm1(SB) + MOVW $1491, R12 + B runtime·callbackasm1(SB) + MOVW $1492, R12 + B runtime·callbackasm1(SB) + MOVW $1493, R12 + B runtime·callbackasm1(SB) + MOVW $1494, R12 + B runtime·callbackasm1(SB) + MOVW $1495, R12 + B runtime·callbackasm1(SB) + MOVW $1496, R12 + B runtime·callbackasm1(SB) + MOVW $1497, R12 + B runtime·callbackasm1(SB) + MOVW $1498, R12 + B runtime·callbackasm1(SB) + MOVW $1499, R12 + B runtime·callbackasm1(SB) + MOVW $1500, R12 + B runtime·callbackasm1(SB) + MOVW $1501, R12 + B runtime·callbackasm1(SB) + MOVW $1502, R12 + B runtime·callbackasm1(SB) + MOVW $1503, R12 + B runtime·callbackasm1(SB) + MOVW $1504, R12 + B runtime·callbackasm1(SB) + MOVW $1505, R12 + B runtime·callbackasm1(SB) + MOVW $1506, R12 + B runtime·callbackasm1(SB) + MOVW $1507, R12 + B runtime·callbackasm1(SB) + MOVW $1508, R12 + B runtime·callbackasm1(SB) + MOVW $1509, R12 + B runtime·callbackasm1(SB) + MOVW $1510, R12 + B runtime·callbackasm1(SB) + MOVW $1511, R12 + B runtime·callbackasm1(SB) + MOVW $1512, R12 + B runtime·callbackasm1(SB) + MOVW $1513, R12 + B runtime·callbackasm1(SB) + MOVW $1514, R12 + B runtime·callbackasm1(SB) + MOVW $1515, R12 + B runtime·callbackasm1(SB) + MOVW $1516, R12 + B runtime·callbackasm1(SB) + MOVW $1517, R12 + B runtime·callbackasm1(SB) + MOVW $1518, R12 + B runtime·callbackasm1(SB) + MOVW $1519, R12 + B runtime·callbackasm1(SB) + MOVW $1520, R12 + B runtime·callbackasm1(SB) + MOVW $1521, R12 + B runtime·callbackasm1(SB) + MOVW $1522, R12 + B runtime·callbackasm1(SB) + MOVW $1523, R12 + B runtime·callbackasm1(SB) + MOVW $1524, R12 + B runtime·callbackasm1(SB) + MOVW $1525, R12 + B runtime·callbackasm1(SB) + MOVW $1526, R12 + B runtime·callbackasm1(SB) + MOVW $1527, R12 + B runtime·callbackasm1(SB) + MOVW $1528, R12 + B runtime·callbackasm1(SB) + MOVW $1529, R12 + B runtime·callbackasm1(SB) + MOVW $1530, R12 + B runtime·callbackasm1(SB) + MOVW $1531, R12 + B runtime·callbackasm1(SB) + MOVW $1532, R12 + B runtime·callbackasm1(SB) + MOVW $1533, R12 + B runtime·callbackasm1(SB) + MOVW $1534, R12 + B runtime·callbackasm1(SB) + MOVW $1535, R12 + B runtime·callbackasm1(SB) + MOVW $1536, R12 + B runtime·callbackasm1(SB) + MOVW $1537, R12 + B runtime·callbackasm1(SB) + MOVW $1538, R12 + B runtime·callbackasm1(SB) + MOVW $1539, R12 + B runtime·callbackasm1(SB) + MOVW $1540, R12 + B runtime·callbackasm1(SB) + MOVW $1541, R12 + B runtime·callbackasm1(SB) + MOVW $1542, R12 + B runtime·callbackasm1(SB) + MOVW $1543, R12 + B runtime·callbackasm1(SB) + MOVW $1544, R12 + B runtime·callbackasm1(SB) + MOVW $1545, R12 + B runtime·callbackasm1(SB) + MOVW $1546, R12 + B runtime·callbackasm1(SB) + MOVW $1547, R12 + B runtime·callbackasm1(SB) + MOVW $1548, R12 + B runtime·callbackasm1(SB) + MOVW $1549, R12 + B runtime·callbackasm1(SB) + MOVW $1550, R12 + B runtime·callbackasm1(SB) + MOVW $1551, R12 + B runtime·callbackasm1(SB) + MOVW $1552, R12 + B runtime·callbackasm1(SB) + MOVW $1553, R12 + B runtime·callbackasm1(SB) + MOVW $1554, R12 + B runtime·callbackasm1(SB) + MOVW $1555, R12 + B runtime·callbackasm1(SB) + MOVW $1556, R12 + B runtime·callbackasm1(SB) + MOVW $1557, R12 + B runtime·callbackasm1(SB) + MOVW $1558, R12 + B runtime·callbackasm1(SB) + MOVW $1559, R12 + B runtime·callbackasm1(SB) + MOVW $1560, R12 + B runtime·callbackasm1(SB) + MOVW $1561, R12 + B runtime·callbackasm1(SB) + MOVW $1562, R12 + B runtime·callbackasm1(SB) + MOVW $1563, R12 + B runtime·callbackasm1(SB) + MOVW $1564, R12 + B runtime·callbackasm1(SB) + MOVW $1565, R12 + B runtime·callbackasm1(SB) + MOVW $1566, R12 + B runtime·callbackasm1(SB) + MOVW $1567, R12 + B runtime·callbackasm1(SB) + MOVW $1568, R12 + B runtime·callbackasm1(SB) + MOVW $1569, R12 + B runtime·callbackasm1(SB) + MOVW $1570, R12 + B runtime·callbackasm1(SB) + MOVW $1571, R12 + B runtime·callbackasm1(SB) + MOVW $1572, R12 + B runtime·callbackasm1(SB) + MOVW $1573, R12 + B runtime·callbackasm1(SB) + MOVW $1574, R12 + B runtime·callbackasm1(SB) + MOVW $1575, R12 + B runtime·callbackasm1(SB) + MOVW $1576, R12 + B runtime·callbackasm1(SB) + MOVW $1577, R12 + B runtime·callbackasm1(SB) + MOVW $1578, R12 + B runtime·callbackasm1(SB) + MOVW $1579, R12 + B runtime·callbackasm1(SB) + MOVW $1580, R12 + B runtime·callbackasm1(SB) + MOVW $1581, R12 + B runtime·callbackasm1(SB) + MOVW $1582, R12 + B runtime·callbackasm1(SB) + MOVW $1583, R12 + B runtime·callbackasm1(SB) + MOVW $1584, R12 + B runtime·callbackasm1(SB) + MOVW $1585, R12 + B runtime·callbackasm1(SB) + MOVW $1586, R12 + B runtime·callbackasm1(SB) + MOVW $1587, R12 + B runtime·callbackasm1(SB) + MOVW $1588, R12 + B runtime·callbackasm1(SB) + MOVW $1589, R12 + B runtime·callbackasm1(SB) + MOVW $1590, R12 + B runtime·callbackasm1(SB) + MOVW $1591, R12 + B runtime·callbackasm1(SB) + MOVW $1592, R12 + B runtime·callbackasm1(SB) + MOVW $1593, R12 + B runtime·callbackasm1(SB) + MOVW $1594, R12 + B runtime·callbackasm1(SB) + MOVW $1595, R12 + B runtime·callbackasm1(SB) + MOVW $1596, R12 + B runtime·callbackasm1(SB) + MOVW $1597, R12 + B runtime·callbackasm1(SB) + MOVW $1598, R12 + B runtime·callbackasm1(SB) + MOVW $1599, R12 + B runtime·callbackasm1(SB) + MOVW $1600, R12 + B runtime·callbackasm1(SB) + MOVW $1601, R12 + B runtime·callbackasm1(SB) + MOVW $1602, R12 + B runtime·callbackasm1(SB) + MOVW $1603, R12 + B runtime·callbackasm1(SB) + MOVW $1604, R12 + B runtime·callbackasm1(SB) + MOVW $1605, R12 + B runtime·callbackasm1(SB) + MOVW $1606, R12 + B runtime·callbackasm1(SB) + MOVW $1607, R12 + B runtime·callbackasm1(SB) + MOVW $1608, R12 + B runtime·callbackasm1(SB) + MOVW $1609, R12 + B runtime·callbackasm1(SB) + MOVW $1610, R12 + B runtime·callbackasm1(SB) + MOVW $1611, R12 + B runtime·callbackasm1(SB) + MOVW $1612, R12 + B runtime·callbackasm1(SB) + MOVW $1613, R12 + B runtime·callbackasm1(SB) + MOVW $1614, R12 + B runtime·callbackasm1(SB) + MOVW $1615, R12 + B runtime·callbackasm1(SB) + MOVW $1616, R12 + B runtime·callbackasm1(SB) + MOVW $1617, R12 + B runtime·callbackasm1(SB) + MOVW $1618, R12 + B runtime·callbackasm1(SB) + MOVW $1619, R12 + B runtime·callbackasm1(SB) + MOVW $1620, R12 + B runtime·callbackasm1(SB) + MOVW $1621, R12 + B runtime·callbackasm1(SB) + MOVW $1622, R12 + B runtime·callbackasm1(SB) + MOVW $1623, R12 + B runtime·callbackasm1(SB) + MOVW $1624, R12 + B runtime·callbackasm1(SB) + MOVW $1625, R12 + B runtime·callbackasm1(SB) + MOVW $1626, R12 + B runtime·callbackasm1(SB) + MOVW $1627, R12 + B runtime·callbackasm1(SB) + MOVW $1628, R12 + B runtime·callbackasm1(SB) + MOVW $1629, R12 + B runtime·callbackasm1(SB) + MOVW $1630, R12 + B runtime·callbackasm1(SB) + MOVW $1631, R12 + B runtime·callbackasm1(SB) + MOVW $1632, R12 + B runtime·callbackasm1(SB) + MOVW $1633, R12 + B runtime·callbackasm1(SB) + MOVW $1634, R12 + B runtime·callbackasm1(SB) + MOVW $1635, R12 + B runtime·callbackasm1(SB) + MOVW $1636, R12 + B runtime·callbackasm1(SB) + MOVW $1637, R12 + B runtime·callbackasm1(SB) + MOVW $1638, R12 + B runtime·callbackasm1(SB) + MOVW $1639, R12 + B runtime·callbackasm1(SB) + MOVW $1640, R12 + B runtime·callbackasm1(SB) + MOVW $1641, R12 + B runtime·callbackasm1(SB) + MOVW $1642, R12 + B runtime·callbackasm1(SB) + MOVW $1643, R12 + B runtime·callbackasm1(SB) + MOVW $1644, R12 + B runtime·callbackasm1(SB) + MOVW $1645, R12 + B runtime·callbackasm1(SB) + MOVW $1646, R12 + B runtime·callbackasm1(SB) + MOVW $1647, R12 + B runtime·callbackasm1(SB) + MOVW $1648, R12 + B runtime·callbackasm1(SB) + MOVW $1649, R12 + B runtime·callbackasm1(SB) + MOVW $1650, R12 + B runtime·callbackasm1(SB) + MOVW $1651, R12 + B runtime·callbackasm1(SB) + MOVW $1652, R12 + B runtime·callbackasm1(SB) + MOVW $1653, R12 + B runtime·callbackasm1(SB) + MOVW $1654, R12 + B runtime·callbackasm1(SB) + MOVW $1655, R12 + B runtime·callbackasm1(SB) + MOVW $1656, R12 + B runtime·callbackasm1(SB) + MOVW $1657, R12 + B runtime·callbackasm1(SB) + MOVW $1658, R12 + B runtime·callbackasm1(SB) + MOVW $1659, R12 + B runtime·callbackasm1(SB) + MOVW $1660, R12 + B runtime·callbackasm1(SB) + MOVW $1661, R12 + B runtime·callbackasm1(SB) + MOVW $1662, R12 + B runtime·callbackasm1(SB) + MOVW $1663, R12 + B runtime·callbackasm1(SB) + MOVW $1664, R12 + B runtime·callbackasm1(SB) + MOVW $1665, R12 + B runtime·callbackasm1(SB) + MOVW $1666, R12 + B runtime·callbackasm1(SB) + MOVW $1667, R12 + B runtime·callbackasm1(SB) + MOVW $1668, R12 + B runtime·callbackasm1(SB) + MOVW $1669, R12 + B runtime·callbackasm1(SB) + MOVW $1670, R12 + B runtime·callbackasm1(SB) + MOVW $1671, R12 + B runtime·callbackasm1(SB) + MOVW $1672, R12 + B runtime·callbackasm1(SB) + MOVW $1673, R12 + B runtime·callbackasm1(SB) + MOVW $1674, R12 + B runtime·callbackasm1(SB) + MOVW $1675, R12 + B runtime·callbackasm1(SB) + MOVW $1676, R12 + B runtime·callbackasm1(SB) + MOVW $1677, R12 + B runtime·callbackasm1(SB) + MOVW $1678, R12 + B runtime·callbackasm1(SB) + MOVW $1679, R12 + B runtime·callbackasm1(SB) + MOVW $1680, R12 + B runtime·callbackasm1(SB) + MOVW $1681, R12 + B runtime·callbackasm1(SB) + MOVW $1682, R12 + B runtime·callbackasm1(SB) + MOVW $1683, R12 + B runtime·callbackasm1(SB) + MOVW $1684, R12 + B runtime·callbackasm1(SB) + MOVW $1685, R12 + B runtime·callbackasm1(SB) + MOVW $1686, R12 + B runtime·callbackasm1(SB) + MOVW $1687, R12 + B runtime·callbackasm1(SB) + MOVW $1688, R12 + B runtime·callbackasm1(SB) + MOVW $1689, R12 + B runtime·callbackasm1(SB) + MOVW $1690, R12 + B runtime·callbackasm1(SB) + MOVW $1691, R12 + B runtime·callbackasm1(SB) + MOVW $1692, R12 + B runtime·callbackasm1(SB) + MOVW $1693, R12 + B runtime·callbackasm1(SB) + MOVW $1694, R12 + B runtime·callbackasm1(SB) + MOVW $1695, R12 + B runtime·callbackasm1(SB) + MOVW $1696, R12 + B runtime·callbackasm1(SB) + MOVW $1697, R12 + B runtime·callbackasm1(SB) + MOVW $1698, R12 + B runtime·callbackasm1(SB) + MOVW $1699, R12 + B runtime·callbackasm1(SB) + MOVW $1700, R12 + B runtime·callbackasm1(SB) + MOVW $1701, R12 + B runtime·callbackasm1(SB) + MOVW $1702, R12 + B runtime·callbackasm1(SB) + MOVW $1703, R12 + B runtime·callbackasm1(SB) + MOVW $1704, R12 + B runtime·callbackasm1(SB) + MOVW $1705, R12 + B runtime·callbackasm1(SB) + MOVW $1706, R12 + B runtime·callbackasm1(SB) + MOVW $1707, R12 + B runtime·callbackasm1(SB) + MOVW $1708, R12 + B runtime·callbackasm1(SB) + MOVW $1709, R12 + B runtime·callbackasm1(SB) + MOVW $1710, R12 + B runtime·callbackasm1(SB) + MOVW $1711, R12 + B runtime·callbackasm1(SB) + MOVW $1712, R12 + B runtime·callbackasm1(SB) + MOVW $1713, R12 + B runtime·callbackasm1(SB) + MOVW $1714, R12 + B runtime·callbackasm1(SB) + MOVW $1715, R12 + B runtime·callbackasm1(SB) + MOVW $1716, R12 + B runtime·callbackasm1(SB) + MOVW $1717, R12 + B runtime·callbackasm1(SB) + MOVW $1718, R12 + B runtime·callbackasm1(SB) + MOVW $1719, R12 + B runtime·callbackasm1(SB) + MOVW $1720, R12 + B runtime·callbackasm1(SB) + MOVW $1721, R12 + B runtime·callbackasm1(SB) + MOVW $1722, R12 + B runtime·callbackasm1(SB) + MOVW $1723, R12 + B runtime·callbackasm1(SB) + MOVW $1724, R12 + B runtime·callbackasm1(SB) + MOVW $1725, R12 + B runtime·callbackasm1(SB) + MOVW $1726, R12 + B runtime·callbackasm1(SB) + MOVW $1727, R12 + B runtime·callbackasm1(SB) + MOVW $1728, R12 + B runtime·callbackasm1(SB) + MOVW $1729, R12 + B runtime·callbackasm1(SB) + MOVW $1730, R12 + B runtime·callbackasm1(SB) + MOVW $1731, R12 + B runtime·callbackasm1(SB) + MOVW $1732, R12 + B runtime·callbackasm1(SB) + MOVW $1733, R12 + B runtime·callbackasm1(SB) + MOVW $1734, R12 + B runtime·callbackasm1(SB) + MOVW $1735, R12 + B runtime·callbackasm1(SB) + MOVW $1736, R12 + B runtime·callbackasm1(SB) + MOVW $1737, R12 + B runtime·callbackasm1(SB) + MOVW $1738, R12 + B runtime·callbackasm1(SB) + MOVW $1739, R12 + B runtime·callbackasm1(SB) + MOVW $1740, R12 + B runtime·callbackasm1(SB) + MOVW $1741, R12 + B runtime·callbackasm1(SB) + MOVW $1742, R12 + B runtime·callbackasm1(SB) + MOVW $1743, R12 + B runtime·callbackasm1(SB) + MOVW $1744, R12 + B runtime·callbackasm1(SB) + MOVW $1745, R12 + B runtime·callbackasm1(SB) + MOVW $1746, R12 + B runtime·callbackasm1(SB) + MOVW $1747, R12 + B runtime·callbackasm1(SB) + MOVW $1748, R12 + B runtime·callbackasm1(SB) + MOVW $1749, R12 + B runtime·callbackasm1(SB) + MOVW $1750, R12 + B runtime·callbackasm1(SB) + MOVW $1751, R12 + B runtime·callbackasm1(SB) + MOVW $1752, R12 + B runtime·callbackasm1(SB) + MOVW $1753, R12 + B runtime·callbackasm1(SB) + MOVW $1754, R12 + B runtime·callbackasm1(SB) + MOVW $1755, R12 + B runtime·callbackasm1(SB) + MOVW $1756, R12 + B runtime·callbackasm1(SB) + MOVW $1757, R12 + B runtime·callbackasm1(SB) + MOVW $1758, R12 + B runtime·callbackasm1(SB) + MOVW $1759, R12 + B runtime·callbackasm1(SB) + MOVW $1760, R12 + B runtime·callbackasm1(SB) + MOVW $1761, R12 + B runtime·callbackasm1(SB) + MOVW $1762, R12 + B runtime·callbackasm1(SB) + MOVW $1763, R12 + B runtime·callbackasm1(SB) + MOVW $1764, R12 + B runtime·callbackasm1(SB) + MOVW $1765, R12 + B runtime·callbackasm1(SB) + MOVW $1766, R12 + B runtime·callbackasm1(SB) + MOVW $1767, R12 + B runtime·callbackasm1(SB) + MOVW $1768, R12 + B runtime·callbackasm1(SB) + MOVW $1769, R12 + B runtime·callbackasm1(SB) + MOVW $1770, R12 + B runtime·callbackasm1(SB) + MOVW $1771, R12 + B runtime·callbackasm1(SB) + MOVW $1772, R12 + B runtime·callbackasm1(SB) + MOVW $1773, R12 + B runtime·callbackasm1(SB) + MOVW $1774, R12 + B runtime·callbackasm1(SB) + MOVW $1775, R12 + B runtime·callbackasm1(SB) + MOVW $1776, R12 + B runtime·callbackasm1(SB) + MOVW $1777, R12 + B runtime·callbackasm1(SB) + MOVW $1778, R12 + B runtime·callbackasm1(SB) + MOVW $1779, R12 + B runtime·callbackasm1(SB) + MOVW $1780, R12 + B runtime·callbackasm1(SB) + MOVW $1781, R12 + B runtime·callbackasm1(SB) + MOVW $1782, R12 + B runtime·callbackasm1(SB) + MOVW $1783, R12 + B runtime·callbackasm1(SB) + MOVW $1784, R12 + B runtime·callbackasm1(SB) + MOVW $1785, R12 + B runtime·callbackasm1(SB) + MOVW $1786, R12 + B runtime·callbackasm1(SB) + MOVW $1787, R12 + B runtime·callbackasm1(SB) + MOVW $1788, R12 + B runtime·callbackasm1(SB) + MOVW $1789, R12 + B runtime·callbackasm1(SB) + MOVW $1790, R12 + B runtime·callbackasm1(SB) + MOVW $1791, R12 + B runtime·callbackasm1(SB) + MOVW $1792, R12 + B runtime·callbackasm1(SB) + MOVW $1793, R12 + B runtime·callbackasm1(SB) + MOVW $1794, R12 + B runtime·callbackasm1(SB) + MOVW $1795, R12 + B runtime·callbackasm1(SB) + MOVW $1796, R12 + B runtime·callbackasm1(SB) + MOVW $1797, R12 + B runtime·callbackasm1(SB) + MOVW $1798, R12 + B runtime·callbackasm1(SB) + MOVW $1799, R12 + B runtime·callbackasm1(SB) + MOVW $1800, R12 + B runtime·callbackasm1(SB) + MOVW $1801, R12 + B runtime·callbackasm1(SB) + MOVW $1802, R12 + B runtime·callbackasm1(SB) + MOVW $1803, R12 + B runtime·callbackasm1(SB) + MOVW $1804, R12 + B runtime·callbackasm1(SB) + MOVW $1805, R12 + B runtime·callbackasm1(SB) + MOVW $1806, R12 + B runtime·callbackasm1(SB) + MOVW $1807, R12 + B runtime·callbackasm1(SB) + MOVW $1808, R12 + B runtime·callbackasm1(SB) + MOVW $1809, R12 + B runtime·callbackasm1(SB) + MOVW $1810, R12 + B runtime·callbackasm1(SB) + MOVW $1811, R12 + B runtime·callbackasm1(SB) + MOVW $1812, R12 + B runtime·callbackasm1(SB) + MOVW $1813, R12 + B runtime·callbackasm1(SB) + MOVW $1814, R12 + B runtime·callbackasm1(SB) + MOVW $1815, R12 + B runtime·callbackasm1(SB) + MOVW $1816, R12 + B runtime·callbackasm1(SB) + MOVW $1817, R12 + B runtime·callbackasm1(SB) + MOVW $1818, R12 + B runtime·callbackasm1(SB) + MOVW $1819, R12 + B runtime·callbackasm1(SB) + MOVW $1820, R12 + B runtime·callbackasm1(SB) + MOVW $1821, R12 + B runtime·callbackasm1(SB) + MOVW $1822, R12 + B runtime·callbackasm1(SB) + MOVW $1823, R12 + B runtime·callbackasm1(SB) + MOVW $1824, R12 + B runtime·callbackasm1(SB) + MOVW $1825, R12 + B runtime·callbackasm1(SB) + MOVW $1826, R12 + B runtime·callbackasm1(SB) + MOVW $1827, R12 + B runtime·callbackasm1(SB) + MOVW $1828, R12 + B runtime·callbackasm1(SB) + MOVW $1829, R12 + B runtime·callbackasm1(SB) + MOVW $1830, R12 + B runtime·callbackasm1(SB) + MOVW $1831, R12 + B runtime·callbackasm1(SB) + MOVW $1832, R12 + B runtime·callbackasm1(SB) + MOVW $1833, R12 + B runtime·callbackasm1(SB) + MOVW $1834, R12 + B runtime·callbackasm1(SB) + MOVW $1835, R12 + B runtime·callbackasm1(SB) + MOVW $1836, R12 + B runtime·callbackasm1(SB) + MOVW $1837, R12 + B runtime·callbackasm1(SB) + MOVW $1838, R12 + B runtime·callbackasm1(SB) + MOVW $1839, R12 + B runtime·callbackasm1(SB) + MOVW $1840, R12 + B runtime·callbackasm1(SB) + MOVW $1841, R12 + B runtime·callbackasm1(SB) + MOVW $1842, R12 + B runtime·callbackasm1(SB) + MOVW $1843, R12 + B runtime·callbackasm1(SB) + MOVW $1844, R12 + B runtime·callbackasm1(SB) + MOVW $1845, R12 + B runtime·callbackasm1(SB) + MOVW $1846, R12 + B runtime·callbackasm1(SB) + MOVW $1847, R12 + B runtime·callbackasm1(SB) + MOVW $1848, R12 + B runtime·callbackasm1(SB) + MOVW $1849, R12 + B runtime·callbackasm1(SB) + MOVW $1850, R12 + B runtime·callbackasm1(SB) + MOVW $1851, R12 + B runtime·callbackasm1(SB) + MOVW $1852, R12 + B runtime·callbackasm1(SB) + MOVW $1853, R12 + B runtime·callbackasm1(SB) + MOVW $1854, R12 + B runtime·callbackasm1(SB) + MOVW $1855, R12 + B runtime·callbackasm1(SB) + MOVW $1856, R12 + B runtime·callbackasm1(SB) + MOVW $1857, R12 + B runtime·callbackasm1(SB) + MOVW $1858, R12 + B runtime·callbackasm1(SB) + MOVW $1859, R12 + B runtime·callbackasm1(SB) + MOVW $1860, R12 + B runtime·callbackasm1(SB) + MOVW $1861, R12 + B runtime·callbackasm1(SB) + MOVW $1862, R12 + B runtime·callbackasm1(SB) + MOVW $1863, R12 + B runtime·callbackasm1(SB) + MOVW $1864, R12 + B runtime·callbackasm1(SB) + MOVW $1865, R12 + B runtime·callbackasm1(SB) + MOVW $1866, R12 + B runtime·callbackasm1(SB) + MOVW $1867, R12 + B runtime·callbackasm1(SB) + MOVW $1868, R12 + B runtime·callbackasm1(SB) + MOVW $1869, R12 + B runtime·callbackasm1(SB) + MOVW $1870, R12 + B runtime·callbackasm1(SB) + MOVW $1871, R12 + B runtime·callbackasm1(SB) + MOVW $1872, R12 + B runtime·callbackasm1(SB) + MOVW $1873, R12 + B runtime·callbackasm1(SB) + MOVW $1874, R12 + B runtime·callbackasm1(SB) + MOVW $1875, R12 + B runtime·callbackasm1(SB) + MOVW $1876, R12 + B runtime·callbackasm1(SB) + MOVW $1877, R12 + B runtime·callbackasm1(SB) + MOVW $1878, R12 + B runtime·callbackasm1(SB) + MOVW $1879, R12 + B runtime·callbackasm1(SB) + MOVW $1880, R12 + B runtime·callbackasm1(SB) + MOVW $1881, R12 + B runtime·callbackasm1(SB) + MOVW $1882, R12 + B runtime·callbackasm1(SB) + MOVW $1883, R12 + B runtime·callbackasm1(SB) + MOVW $1884, R12 + B runtime·callbackasm1(SB) + MOVW $1885, R12 + B runtime·callbackasm1(SB) + MOVW $1886, R12 + B runtime·callbackasm1(SB) + MOVW $1887, R12 + B runtime·callbackasm1(SB) + MOVW $1888, R12 + B runtime·callbackasm1(SB) + MOVW $1889, R12 + B runtime·callbackasm1(SB) + MOVW $1890, R12 + B runtime·callbackasm1(SB) + MOVW $1891, R12 + B runtime·callbackasm1(SB) + MOVW $1892, R12 + B runtime·callbackasm1(SB) + MOVW $1893, R12 + B runtime·callbackasm1(SB) + MOVW $1894, R12 + B runtime·callbackasm1(SB) + MOVW $1895, R12 + B runtime·callbackasm1(SB) + MOVW $1896, R12 + B runtime·callbackasm1(SB) + MOVW $1897, R12 + B runtime·callbackasm1(SB) + MOVW $1898, R12 + B runtime·callbackasm1(SB) + MOVW $1899, R12 + B runtime·callbackasm1(SB) + MOVW $1900, R12 + B runtime·callbackasm1(SB) + MOVW $1901, R12 + B runtime·callbackasm1(SB) + MOVW $1902, R12 + B runtime·callbackasm1(SB) + MOVW $1903, R12 + B runtime·callbackasm1(SB) + MOVW $1904, R12 + B runtime·callbackasm1(SB) + MOVW $1905, R12 + B runtime·callbackasm1(SB) + MOVW $1906, R12 + B runtime·callbackasm1(SB) + MOVW $1907, R12 + B runtime·callbackasm1(SB) + MOVW $1908, R12 + B runtime·callbackasm1(SB) + MOVW $1909, R12 + B runtime·callbackasm1(SB) + MOVW $1910, R12 + B runtime·callbackasm1(SB) + MOVW $1911, R12 + B runtime·callbackasm1(SB) + MOVW $1912, R12 + B runtime·callbackasm1(SB) + MOVW $1913, R12 + B runtime·callbackasm1(SB) + MOVW $1914, R12 + B runtime·callbackasm1(SB) + MOVW $1915, R12 + B runtime·callbackasm1(SB) + MOVW $1916, R12 + B runtime·callbackasm1(SB) + MOVW $1917, R12 + B runtime·callbackasm1(SB) + MOVW $1918, R12 + B runtime·callbackasm1(SB) + MOVW $1919, R12 + B runtime·callbackasm1(SB) + MOVW $1920, R12 + B runtime·callbackasm1(SB) + MOVW $1921, R12 + B runtime·callbackasm1(SB) + MOVW $1922, R12 + B runtime·callbackasm1(SB) + MOVW $1923, R12 + B runtime·callbackasm1(SB) + MOVW $1924, R12 + B runtime·callbackasm1(SB) + MOVW $1925, R12 + B runtime·callbackasm1(SB) + MOVW $1926, R12 + B runtime·callbackasm1(SB) + MOVW $1927, R12 + B runtime·callbackasm1(SB) + MOVW $1928, R12 + B runtime·callbackasm1(SB) + MOVW $1929, R12 + B runtime·callbackasm1(SB) + MOVW $1930, R12 + B runtime·callbackasm1(SB) + MOVW $1931, R12 + B runtime·callbackasm1(SB) + MOVW $1932, R12 + B runtime·callbackasm1(SB) + MOVW $1933, R12 + B runtime·callbackasm1(SB) + MOVW $1934, R12 + B runtime·callbackasm1(SB) + MOVW $1935, R12 + B runtime·callbackasm1(SB) + MOVW $1936, R12 + B runtime·callbackasm1(SB) + MOVW $1937, R12 + B runtime·callbackasm1(SB) + MOVW $1938, R12 + B runtime·callbackasm1(SB) + MOVW $1939, R12 + B runtime·callbackasm1(SB) + MOVW $1940, R12 + B runtime·callbackasm1(SB) + MOVW $1941, R12 + B runtime·callbackasm1(SB) + MOVW $1942, R12 + B runtime·callbackasm1(SB) + MOVW $1943, R12 + B runtime·callbackasm1(SB) + MOVW $1944, R12 + B runtime·callbackasm1(SB) + MOVW $1945, R12 + B runtime·callbackasm1(SB) + MOVW $1946, R12 + B runtime·callbackasm1(SB) + MOVW $1947, R12 + B runtime·callbackasm1(SB) + MOVW $1948, R12 + B runtime·callbackasm1(SB) + MOVW $1949, R12 + B runtime·callbackasm1(SB) + MOVW $1950, R12 + B runtime·callbackasm1(SB) + MOVW $1951, R12 + B runtime·callbackasm1(SB) + MOVW $1952, R12 + B runtime·callbackasm1(SB) + MOVW $1953, R12 + B runtime·callbackasm1(SB) + MOVW $1954, R12 + B runtime·callbackasm1(SB) + MOVW $1955, R12 + B runtime·callbackasm1(SB) + MOVW $1956, R12 + B runtime·callbackasm1(SB) + MOVW $1957, R12 + B runtime·callbackasm1(SB) + MOVW $1958, R12 + B runtime·callbackasm1(SB) + MOVW $1959, R12 + B runtime·callbackasm1(SB) + MOVW $1960, R12 + B runtime·callbackasm1(SB) + MOVW $1961, R12 + B runtime·callbackasm1(SB) + MOVW $1962, R12 + B runtime·callbackasm1(SB) + MOVW $1963, R12 + B runtime·callbackasm1(SB) + MOVW $1964, R12 + B runtime·callbackasm1(SB) + MOVW $1965, R12 + B runtime·callbackasm1(SB) + MOVW $1966, R12 + B runtime·callbackasm1(SB) + MOVW $1967, R12 + B runtime·callbackasm1(SB) + MOVW $1968, R12 + B runtime·callbackasm1(SB) + MOVW $1969, R12 + B runtime·callbackasm1(SB) + MOVW $1970, R12 + B runtime·callbackasm1(SB) + MOVW $1971, R12 + B runtime·callbackasm1(SB) + MOVW $1972, R12 + B runtime·callbackasm1(SB) + MOVW $1973, R12 + B runtime·callbackasm1(SB) + MOVW $1974, R12 + B runtime·callbackasm1(SB) + MOVW $1975, R12 + B runtime·callbackasm1(SB) + MOVW $1976, R12 + B runtime·callbackasm1(SB) + MOVW $1977, R12 + B runtime·callbackasm1(SB) + MOVW $1978, R12 + B runtime·callbackasm1(SB) + MOVW $1979, R12 + B runtime·callbackasm1(SB) + MOVW $1980, R12 + B runtime·callbackasm1(SB) + MOVW $1981, R12 + B runtime·callbackasm1(SB) + MOVW $1982, R12 + B runtime·callbackasm1(SB) + MOVW $1983, R12 + B runtime·callbackasm1(SB) + MOVW $1984, R12 + B runtime·callbackasm1(SB) + MOVW $1985, R12 + B runtime·callbackasm1(SB) + MOVW $1986, R12 + B runtime·callbackasm1(SB) + MOVW $1987, R12 + B runtime·callbackasm1(SB) + MOVW $1988, R12 + B runtime·callbackasm1(SB) + MOVW $1989, R12 + B runtime·callbackasm1(SB) + MOVW $1990, R12 + B runtime·callbackasm1(SB) + MOVW $1991, R12 + B runtime·callbackasm1(SB) + MOVW $1992, R12 + B runtime·callbackasm1(SB) + MOVW $1993, R12 + B runtime·callbackasm1(SB) + MOVW $1994, R12 + B runtime·callbackasm1(SB) + MOVW $1995, R12 + B runtime·callbackasm1(SB) + MOVW $1996, R12 + B runtime·callbackasm1(SB) + MOVW $1997, R12 + B runtime·callbackasm1(SB) + MOVW $1998, R12 + B runtime·callbackasm1(SB) + MOVW $1999, R12 + B runtime·callbackasm1(SB) diff --git a/src/strings/example_test.go b/src/strings/example_test.go index 607e4a0a70..103ef51f29 100644 --- a/src/strings/example_test.go +++ b/src/strings/example_test.go @@ -199,7 +199,7 @@ func ExampleRepeat() { func ExampleReplace() { fmt.Println(strings.Replace("oink oink oink", "k", "ky", 2)) - fmt.Println(strings.Replace("oink oink oink", "oink", "moo", -1)) + fmt.Println(strings.ReplaceAll("oink oink oink", "oink", "moo")) // Output: // oinky oinky oink // moo moo moo diff --git a/src/strings/replace.go b/src/strings/replace.go index dbda950194..9ddf5e1e3f 100644 --- a/src/strings/replace.go +++ b/src/strings/replace.go @@ -308,10 +308,6 @@ func (w *appendSliceWriter) WriteString(s string) (int, error) { return len(s), nil } -type stringWriterIface interface { - WriteString(string) (int, error) -} - type stringWriter struct { w io.Writer } @@ -320,8 +316,8 @@ func (w stringWriter) WriteString(s string) (int, error) { return w.w.Write([]byte(s)) } -func getStringWriter(w io.Writer) stringWriterIface { - sw, ok := w.(stringWriterIface) +func getStringWriter(w io.Writer) io.StringWriter { + sw, ok := w.(io.StringWriter) if !ok { sw = stringWriter{w} } diff --git a/src/strings/strings.go b/src/strings/strings.go index df95715ec8..ecc8c97d9e 100644 --- a/src/strings/strings.go +++ b/src/strings/strings.go @@ -463,27 +463,27 @@ func Map(mapping func(rune) rune, s string) string { for i, c := range s { r := mapping(c) - if r == c { + if r == c && c != utf8.RuneError { continue } + var width int + if c == utf8.RuneError { + c, width = utf8.DecodeRuneInString(s[i:]) + if width != 1 && r == c { + continue + } + } else { + width = utf8.RuneLen(c) + } + b.Grow(len(s) + utf8.UTFMax) b.WriteString(s[:i]) if r >= 0 { b.WriteRune(r) } - if c == utf8.RuneError { - // RuneError is the result of either decoding - // an invalid sequence or '\uFFFD'. Determine - // the correct number of bytes we need to advance. - _, w := utf8.DecodeRuneInString(s[i:]) - i += w - } else { - i += utf8.RuneLen(c) - } - - s = s[i:] + s = s[i+width:] break } @@ -561,15 +561,16 @@ func ToUpper(s string) string { if !hasLower { return s } - b := make([]byte, len(s)) + var b Builder + b.Grow(len(s)) for i := 0; i < len(s); i++ { c := s[i] if c >= 'a' && c <= 'z' { c -= 'a' - 'A' } - b[i] = c + b.WriteByte(c) } - return string(b) + return b.String() } return Map(unicode.ToUpper, s) } @@ -590,15 +591,16 @@ func ToLower(s string) string { if !hasUpper { return s } - b := make([]byte, len(s)) + var b Builder + b.Grow(len(s)) for i := 0; i < len(s); i++ { c := s[i] if c >= 'A' && c <= 'Z' { c += 'a' - 'A' } - b[i] = c + b.WriteByte(c) } - return string(b) + return b.String() } return Map(unicode.ToLower, s) } @@ -872,6 +874,15 @@ func Replace(s, old, new string, n int) string { return string(t[0:w]) } +// ReplaceAll returns a copy of the string s with all +// non-overlapping instances of old replaced by new. +// If old is empty, it matches at the beginning of the string +// and after each UTF-8 sequence, yielding up to k+1 replacements +// for a k-rune string. +func ReplaceAll(s, old, new string) string { + return Replace(s, old, new, -1) +} + // EqualFold reports whether s and t, interpreted as UTF-8 strings, // are equal under Unicode case-folding. func EqualFold(s, t string) bool { @@ -947,21 +958,22 @@ func Index(s, substr string) int { if len(s) <= bytealg.MaxBruteForce { return bytealg.IndexString(s, substr) } - c := substr[0] + c0 := substr[0] + c1 := substr[1] i := 0 - t := s[:len(s)-n+1] + t := len(s) - n + 1 fails := 0 - for i < len(t) { - if t[i] != c { + for i < t { + if s[i] != c0 { // IndexByte is faster than bytealg.IndexString, so use it as long as // we're not getting lots of false positives. - o := IndexByte(t[i:], c) + o := IndexByte(s[i:t], c0) if o < 0 { return -1 } i += o } - if s[i:i+n] == substr { + if s[i+1] == c1 && s[i:i+n] == substr { return i } fails++ @@ -977,24 +989,25 @@ func Index(s, substr string) int { } return -1 } - c := substr[0] + c0 := substr[0] + c1 := substr[1] i := 0 - t := s[:len(s)-n+1] + t := len(s) - n + 1 fails := 0 - for i < len(t) { - if t[i] != c { - o := IndexByte(t[i:], c) + for i < t { + if s[i] != c0 { + o := IndexByte(s[i:t], c0) if o < 0 { return -1 } i += o } - if s[i:i+n] == substr { + if s[i+1] == c1 && s[i:i+n] == substr { return i } i++ fails++ - if fails >= 4+i>>4 && i < len(t) { + if fails >= 4+i>>4 && i < t { // See comment in ../bytes/bytes_generic.go. j := indexRabinKarp(s[i:], substr) if j < 0 { diff --git a/src/strings/strings_test.go b/src/strings/strings_test.go index 20bc484f39..eee2dd55df 100644 --- a/src/strings/strings_test.go +++ b/src/strings/strings_test.go @@ -646,10 +646,10 @@ func TestMap(t *testing.T) { if unicode.Is(unicode.Latin, r) { return r } - return '?' + return utf8.RuneError } m = Map(replaceNotLatin, "Hello\255World") - expect = "Hello?World" + expect = "Hello\uFFFDWorld" if m != expect { t.Errorf("replace invalid sequence: expected %q got %q", expect, m) } @@ -1243,6 +1243,12 @@ func TestReplace(t *testing.T) { if s := Replace(tt.in, tt.old, tt.new, tt.n); s != tt.out { t.Errorf("Replace(%q, %q, %q, %d) = %q, want %q", tt.in, tt.old, tt.new, tt.n, s, tt.out) } + if tt.n == -1 { + s := ReplaceAll(tt.in, tt.old, tt.new) + if s != tt.out { + t.Errorf("ReplaceAll(%q, %q, %q) = %q, want %q", tt.in, tt.old, tt.new, s, tt.out) + } + } } } diff --git a/src/sync/map.go b/src/sync/map.go index c4a0dc4194..c6aa308856 100644 --- a/src/sync/map.go +++ b/src/sync/map.go @@ -167,18 +167,14 @@ func (m *Map) Store(key, value interface{}) { // If the entry is expunged, tryStore returns false and leaves the entry // unchanged. func (e *entry) tryStore(i *interface{}) bool { - p := atomic.LoadPointer(&e.p) - if p == expunged { - return false - } for { - if atomic.CompareAndSwapPointer(&e.p, p, unsafe.Pointer(i)) { - return true - } - p = atomic.LoadPointer(&e.p) + p := atomic.LoadPointer(&e.p) if p == expunged { return false } + if atomic.CompareAndSwapPointer(&e.p, p, unsafe.Pointer(i)) { + return true + } } } diff --git a/src/syscall/asm_nacl_386.s b/src/syscall/asm_nacl_386.s index 9d1e541c7c..b989171120 100644 --- a/src/syscall/asm_nacl_386.s +++ b/src/syscall/asm_nacl_386.s @@ -42,4 +42,4 @@ ok: MOVL DX, r2+20(FP) MOVL $0, err+24(FP) CALL runtime·exitsyscall(SB) - RET + RET diff --git a/src/syscall/asm_nacl_amd64p32.s b/src/syscall/asm_nacl_amd64p32.s index b8c097b539..816f7dccfb 100644 --- a/src/syscall/asm_nacl_amd64p32.s +++ b/src/syscall/asm_nacl_amd64p32.s @@ -39,4 +39,4 @@ ok: MOVL DX, r2+20(FP) MOVL $0, err+24(FP) CALL runtime·exitsyscall(SB) - RET + RET diff --git a/src/syscall/asm_nacl_arm.s b/src/syscall/asm_nacl_arm.s index 3e7df1aadf..6092afd9e6 100644 --- a/src/syscall/asm_nacl_arm.s +++ b/src/syscall/asm_nacl_arm.s @@ -41,4 +41,4 @@ ok: MOVW $0, R2 MOVW R2, err+24(FP) BL runtime·exitsyscall(SB) - RET + RET diff --git a/src/syscall/asm_plan9_386.s b/src/syscall/asm_plan9_386.s index 65ae6c77fb..7a2c2daaaa 100644 --- a/src/syscall/asm_plan9_386.s +++ b/src/syscall/asm_plan9_386.s @@ -45,11 +45,11 @@ TEXT ·Syscall(SB),NOSPLIT,$148-32 CALL runtime·gostring(SB) LEAL str-144(SP), SI JMP copyresult3 - + ok3: CALL runtime·exitsyscall(SB) LEAL ·emptystring(SB), SI - + copyresult3: LEAL err+24(FP), DI @@ -78,7 +78,7 @@ TEXT ·Syscall6(SB),NOSPLIT,$148-44 MOVL $0, r2+32(FP) CMPL AX, $-1 JNE ok4 - + LEAL errbuf-128(SP), AX MOVL AX, sysargs-144(SP) MOVL $128, sysargs1-140(SP) @@ -90,11 +90,11 @@ TEXT ·Syscall6(SB),NOSPLIT,$148-44 CALL runtime·gostring(SB) LEAL str-144(SP), SI JMP copyresult4 - + ok4: CALL runtime·exitsyscall(SB) LEAL ·emptystring(SB), SI - + copyresult4: LEAL err+36(FP), DI @@ -144,7 +144,7 @@ TEXT ·seek(SB),NOSPLIT,$24-36 NO_LOCAL_POINTERS LEAL newoffset+20(FP), AX MOVL AX, placeholder+0(FP) - + // copy args down LEAL placeholder+0(FP), SI LEAL sysargs-20(SP), DI @@ -156,19 +156,19 @@ TEXT ·seek(SB),NOSPLIT,$24-36 MOVSL MOVL $SYS_SEEK, AX // syscall entry INT $64 - + CMPL AX, $-1 JNE ok6 MOVL AX, newoffset_lo+20(FP) MOVL AX, newoffset_hi+24(FP) - + CALL syscall·errstr(SB) MOVL SP, SI JMP copyresult6 - + ok6: LEAL ·emptystring(SB), SI - + copyresult6: LEAL err+28(FP), DI diff --git a/src/syscall/asm_plan9_amd64.s b/src/syscall/asm_plan9_amd64.s index bba4012e5c..d5c9f6c63f 100644 --- a/src/syscall/asm_plan9_amd64.s +++ b/src/syscall/asm_plan9_amd64.s @@ -44,11 +44,11 @@ TEXT ·Syscall(SB),NOSPLIT,$168-64 CALL runtime·gostring(SB) LEAQ str-160(SP), SI JMP copyresult3 - + ok3: CALL runtime·exitsyscall(SB) LEAQ ·emptystring(SB), SI - + copyresult3: LEAQ err+48(FP), DI @@ -77,7 +77,7 @@ TEXT ·Syscall6(SB),NOSPLIT,$168-88 MOVQ $0, r2+64(FP) CMPL AX, $-1 JNE ok4 - + LEAQ errbuf-128(SP), AX MOVQ AX, sysargs-160(SP) MOVQ $128, sysargs1-152(SP) @@ -89,11 +89,11 @@ TEXT ·Syscall6(SB),NOSPLIT,$168-88 CALL runtime·gostring(SB) LEAQ str-160(SP), SI JMP copyresult4 - + ok4: CALL runtime·exitsyscall(SB) LEAQ ·emptystring(SB), SI - + copyresult4: LEAQ err+72(FP), DI @@ -143,7 +143,7 @@ TEXT ·seek(SB),NOSPLIT,$48-56 NO_LOCAL_POINTERS LEAQ newoffset+32(FP), AX MOVQ AX, placeholder+0(FP) - + // copy args down LEAQ placeholder+0(FP), SI LEAQ sysargs-40(SP), DI @@ -155,18 +155,18 @@ TEXT ·seek(SB),NOSPLIT,$48-56 MOVSQ MOVQ $SYS_SEEK, BP // syscall entry SYSCALL - + CMPL AX, $-1 JNE ok6 MOVQ AX, newoffset+32(FP) - + CALL syscall·errstr(SB) MOVQ SP, SI JMP copyresult6 - + ok6: LEAQ ·emptystring(SB), SI - + copyresult6: LEAQ err+40(FP), DI diff --git a/src/syscall/syscall_linux_386.go b/src/syscall/syscall_linux_386.go index 49db72450f..6e162ebb41 100644 --- a/src/syscall/syscall_linux_386.go +++ b/src/syscall/syscall_linux_386.go @@ -62,8 +62,6 @@ func Pipe2(p []int, flags int) (err error) { //sysnb InotifyInit() (fd int, err error) //sys Ioperm(from int, num int, on int) (err error) //sys Iopl(level int) (err error) -//sys Lchown(path string, uid int, gid int) (err error) = SYS_LCHOWN32 -//sys Lstat(path string, stat *Stat_t) (err error) = SYS_LSTAT64 //sys Pread(fd int, p []byte, offset int64) (n int, err error) = SYS_PREAD64 //sys Pwrite(fd int, p []byte, offset int64) (n int, err error) = SYS_PWRITE64 //sys sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) = SYS_SENDFILE64 @@ -74,7 +72,6 @@ func Pipe2(p []int, flags int) (err error) { //sysnb Setresuid(ruid int, euid int, suid int) (err error) = SYS_SETRESUID32 //sysnb Setreuid(ruid int, euid int) (err error) = SYS_SETREUID32 //sys Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int, err error) -//sys Stat(path string, stat *Stat_t) (err error) = SYS_STAT64 //sys SyncFileRange(fd int, off int64, n int64, flags int) (err error) //sys Truncate(path string, length int64) (err error) = SYS_TRUNCATE64 //sysnb getgroups(n int, list *_Gid_t) (nn int, err error) = SYS_GETGROUPS32 @@ -84,6 +81,18 @@ func Pipe2(p []int, flags int) (err error) { //sys mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset uintptr) (xaddr uintptr, err error) //sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) +func Stat(path string, stat *Stat_t) (err error) { + return fstatat(_AT_FDCWD, path, stat, 0) +} + +func Lchown(path string, uid int, gid int) (err error) { + return Fchownat(_AT_FDCWD, path, uid, gid, _AT_SYMLINK_NOFOLLOW) +} + +func Lstat(path string, stat *Stat_t) (err error) { + return fstatat(_AT_FDCWD, path, stat, _AT_SYMLINK_NOFOLLOW) +} + func mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error) { page := uintptr(offset / 4096) if offset != int64(page)*4096 { diff --git a/src/syscall/syscall_linux_amd64.go b/src/syscall/syscall_linux_amd64.go index 1a21d9db6f..f740ab4e72 100644 --- a/src/syscall/syscall_linux_amd64.go +++ b/src/syscall/syscall_linux_amd64.go @@ -22,9 +22,7 @@ const ( //sysnb InotifyInit() (fd int, err error) //sys Ioperm(from int, num int, on int) (err error) //sys Iopl(level int) (err error) -//sys Lchown(path string, uid int, gid int) (err error) //sys Listen(s int, n int) (err error) -//sys Lstat(path string, stat *Stat_t) (err error) //sys Pread(fd int, p []byte, offset int64) (n int, err error) = SYS_PREAD64 //sys Pwrite(fd int, p []byte, offset int64) (n int, err error) = SYS_PWRITE64 //sys Seek(fd int, offset int64, whence int) (off int64, err error) = SYS_LSEEK @@ -66,6 +64,14 @@ func Stat(path string, stat *Stat_t) (err error) { return fstatat(_AT_FDCWD, path, stat, 0) } +func Lchown(path string, uid int, gid int) (err error) { + return Fchownat(_AT_FDCWD, path, uid, gid, _AT_SYMLINK_NOFOLLOW) +} + +func Lstat(path string, stat *Stat_t) (err error) { + return fstatat(_AT_FDCWD, path, stat, _AT_SYMLINK_NOFOLLOW) +} + //go:noescape func gettimeofday(tv *Timeval) (err Errno) diff --git a/src/syscall/syscall_linux_arm.go b/src/syscall/syscall_linux_arm.go index b0c0ac7c4f..65543193e1 100644 --- a/src/syscall/syscall_linux_arm.go +++ b/src/syscall/syscall_linux_arm.go @@ -83,9 +83,7 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) { //sysnb Getgid() (gid int) = SYS_GETGID32 //sysnb Getuid() (uid int) = SYS_GETUID32 //sysnb InotifyInit() (fd int, err error) -//sys Lchown(path string, uid int, gid int) (err error) = SYS_LCHOWN32 //sys Listen(s int, n int) (err error) -//sys Lstat(path string, stat *Stat_t) (err error) = SYS_LSTAT64 //sys sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) = SYS_SENDFILE64 //sys Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error) = SYS__NEWSELECT //sys Setfsgid(gid int) (err error) = SYS_SETFSGID32 @@ -96,7 +94,6 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) { //sysnb Setreuid(ruid int, euid int) (err error) = SYS_SETREUID32 //sys Shutdown(fd int, how int) (err error) //sys Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int, err error) -//sys Stat(path string, stat *Stat_t) (err error) = SYS_STAT64 // Vsyscalls on amd64. //sysnb Gettimeofday(tv *Timeval) (err error) @@ -110,6 +107,18 @@ func Seek(fd int, offset int64, whence int) (newoffset int64, err error) { //sys mmap2(addr uintptr, length uintptr, prot int, flags int, fd int, pageOffset uintptr) (xaddr uintptr, err error) //sys EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error) +func Stat(path string, stat *Stat_t) (err error) { + return fstatat(_AT_FDCWD, path, stat, 0) +} + +func Lchown(path string, uid int, gid int) (err error) { + return Fchownat(_AT_FDCWD, path, uid, gid, _AT_SYMLINK_NOFOLLOW) +} + +func Lstat(path string, stat *Stat_t) (err error) { + return fstatat(_AT_FDCWD, path, stat, _AT_SYMLINK_NOFOLLOW) +} + func Fstatfs(fd int, buf *Statfs_t) (err error) { _, _, e := Syscall(SYS_FSTATFS64, uintptr(fd), unsafe.Sizeof(*buf), uintptr(unsafe.Pointer(buf))) if e != 0 { diff --git a/src/syscall/syscall_linux_test.go b/src/syscall/syscall_linux_test.go index 1fd70b07e3..293549a841 100644 --- a/src/syscall/syscall_linux_test.go +++ b/src/syscall/syscall_linux_test.go @@ -19,6 +19,7 @@ import ( "syscall" "testing" "time" + "unsafe" ) // chtmpdir changes the working directory to a new temporary directory and @@ -294,7 +295,7 @@ func TestSyscallNoError(t *testing.T) { // On Linux there are currently no syscalls which don't fail and return // a value larger than 0xfffffffffffff001 so we could test RawSyscall // vs. RawSyscallNoError on 64bit architectures. - if runtime.GOARCH != "386" && runtime.GOARCH != "arm" { + if unsafe.Sizeof(uintptr(0)) != 4 { t.Skip("skipping on non-32bit architecture") } diff --git a/src/syscall/zsyscall_linux_386.go b/src/syscall/zsyscall_linux_386.go index 62827f16dc..0882494c47 100644 --- a/src/syscall/zsyscall_linux_386.go +++ b/src/syscall/zsyscall_linux_386.go @@ -1276,36 +1276,6 @@ func Iopl(level int) (err error) { // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT -func Lchown(path string, uid int, gid int) (err error) { - var _p0 *byte - _p0, err = BytePtrFromString(path) - if err != nil { - return - } - _, _, e1 := Syscall(SYS_LCHOWN32, uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid)) - if e1 != 0 { - err = errnoErr(e1) - } - return -} - -// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT - -func Lstat(path string, stat *Stat_t) (err error) { - var _p0 *byte - _p0, err = BytePtrFromString(path) - if err != nil { - return - } - _, _, e1 := Syscall(SYS_LSTAT64, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0) - if e1 != 0 { - err = errnoErr(e1) - } - return -} - -// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT - func Pread(fd int, p []byte, offset int64) (n int, err error) { var _p0 unsafe.Pointer if len(p) > 0 { @@ -1422,21 +1392,6 @@ func Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n i // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT -func Stat(path string, stat *Stat_t) (err error) { - var _p0 *byte - _p0, err = BytePtrFromString(path) - if err != nil { - return - } - _, _, e1 := Syscall(SYS_STAT64, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0) - if e1 != 0 { - err = errnoErr(e1) - } - return -} - -// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT - func SyncFileRange(fd int, off int64, n int64, flags int) (err error) { _, _, e1 := Syscall6(SYS_SYNC_FILE_RANGE, uintptr(fd), uintptr(off), uintptr(off>>32), uintptr(n), uintptr(n>>32), uintptr(flags)) if e1 != 0 { diff --git a/src/syscall/zsyscall_linux_amd64.go b/src/syscall/zsyscall_linux_amd64.go index b6638269be..9f2046bf93 100644 --- a/src/syscall/zsyscall_linux_amd64.go +++ b/src/syscall/zsyscall_linux_amd64.go @@ -1261,21 +1261,6 @@ func Iopl(level int) (err error) { // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT -func Lchown(path string, uid int, gid int) (err error) { - var _p0 *byte - _p0, err = BytePtrFromString(path) - if err != nil { - return - } - _, _, e1 := Syscall(SYS_LCHOWN, uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid)) - if e1 != 0 { - err = errnoErr(e1) - } - return -} - -// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT - func Listen(s int, n int) (err error) { _, _, e1 := Syscall(SYS_LISTEN, uintptr(s), uintptr(n), 0) if e1 != 0 { @@ -1286,21 +1271,6 @@ func Listen(s int, n int) (err error) { // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT -func Lstat(path string, stat *Stat_t) (err error) { - var _p0 *byte - _p0, err = BytePtrFromString(path) - if err != nil { - return - } - _, _, e1 := Syscall(SYS_LSTAT, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0) - if e1 != 0 { - err = errnoErr(e1) - } - return -} - -// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT - func Pread(fd int, p []byte, offset int64) (n int, err error) { var _p0 unsafe.Pointer if len(p) > 0 { diff --git a/src/syscall/zsyscall_linux_arm.go b/src/syscall/zsyscall_linux_arm.go index bb20d6e946..3d099aa16d 100644 --- a/src/syscall/zsyscall_linux_arm.go +++ b/src/syscall/zsyscall_linux_arm.go @@ -1415,21 +1415,6 @@ func InotifyInit() (fd int, err error) { // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT -func Lchown(path string, uid int, gid int) (err error) { - var _p0 *byte - _p0, err = BytePtrFromString(path) - if err != nil { - return - } - _, _, e1 := Syscall(SYS_LCHOWN32, uintptr(unsafe.Pointer(_p0)), uintptr(uid), uintptr(gid)) - if e1 != 0 { - err = errnoErr(e1) - } - return -} - -// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT - func Listen(s int, n int) (err error) { _, _, e1 := Syscall(SYS_LISTEN, uintptr(s), uintptr(n), 0) if e1 != 0 { @@ -1440,21 +1425,6 @@ func Listen(s int, n int) (err error) { // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT -func Lstat(path string, stat *Stat_t) (err error) { - var _p0 *byte - _p0, err = BytePtrFromString(path) - if err != nil { - return - } - _, _, e1 := Syscall(SYS_LSTAT64, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0) - if e1 != 0 { - err = errnoErr(e1) - } - return -} - -// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT - func sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) { r0, _, e1 := Syscall6(SYS_SENDFILE64, uintptr(outfd), uintptr(infd), uintptr(unsafe.Pointer(offset)), uintptr(count), 0, 0) written = int(r0) @@ -1558,21 +1528,6 @@ func Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n i // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT -func Stat(path string, stat *Stat_t) (err error) { - var _p0 *byte - _p0, err = BytePtrFromString(path) - if err != nil { - return - } - _, _, e1 := Syscall(SYS_STAT64, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(stat)), 0) - if e1 != 0 { - err = errnoErr(e1) - } - return -} - -// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT - func Gettimeofday(tv *Timeval) (err error) { _, _, e1 := RawSyscall(SYS_GETTIMEOFDAY, uintptr(unsafe.Pointer(tv)), 0, 0) if e1 != 0 { diff --git a/src/testdata/Isaac.Newton-Opticks.txt b/src/testdata/Isaac.Newton-Opticks.txt new file mode 100644 index 0000000000..15bb4c54d0 --- /dev/null +++ b/src/testdata/Isaac.Newton-Opticks.txt @@ -0,0 +1,9286 @@ +Produced by Suzanne Lybarger, steve harris, Josephine +Paolucci and the Online Distributed Proofreading Team at +http://www.pgdp.net. + + + + + + +OPTICKS: + +OR, A + +TREATISE + +OF THE + +_Reflections_, _Refractions_, +_Inflections_ and _Colours_ + +OF + +LIGHT. + +_The_ FOURTH EDITION, _corrected_. + +By Sir _ISAAC NEWTON_, Knt. + +LONDON: + +Printed for WILLIAM INNYS at the West-End of St. _Paul's_. MDCCXXX. + +TITLE PAGE OF THE 1730 EDITION + + + + +SIR ISAAC NEWTON'S ADVERTISEMENTS + + + + +Advertisement I + + +_Part of the ensuing Discourse about Light was written at the Desire of +some Gentlemen of the_ Royal-Society, _in the Year 1675, and then sent +to their Secretary, and read at their Meetings, and the rest was added +about twelve Years after to complete the Theory; except the third Book, +and the last Proposition of the Second, which were since put together +out of scatter'd Papers. To avoid being engaged in Disputes about these +Matters, I have hitherto delayed the printing, and should still have +delayed it, had not the Importunity of Friends prevailed upon me. If any +other Papers writ on this Subject are got out of my Hands they are +imperfect, and were perhaps written before I had tried all the +Experiments here set down, and fully satisfied my self about the Laws of +Refractions and Composition of Colours. I have here publish'd what I +think proper to come abroad, wishing that it may not be translated into +another Language without my Consent._ + +_The Crowns of Colours, which sometimes appear about the Sun and Moon, I +have endeavoured to give an Account of; but for want of sufficient +Observations leave that Matter to be farther examined. The Subject of +the Third Book I have also left imperfect, not having tried all the +Experiments which I intended when I was about these Matters, nor +repeated some of those which I did try, until I had satisfied my self +about all their Circumstances. To communicate what I have tried, and +leave the rest to others for farther Enquiry, is all my Design in +publishing these Papers._ + +_In a Letter written to Mr._ Leibnitz _in the year 1679, and published +by Dr._ Wallis, _I mention'd a Method by which I had found some general +Theorems about squaring Curvilinear Figures, or comparing them with the +Conic Sections, or other the simplest Figures with which they may be +compared. And some Years ago I lent out a Manuscript containing such +Theorems, and having since met with some Things copied out of it, I have +on this Occasion made it publick, prefixing to it an_ Introduction, _and +subjoining a_ Scholium _concerning that Method. And I have joined with +it another small Tract concerning the Curvilinear Figures of the Second +Kind, which was also written many Years ago, and made known to some +Friends, who have solicited the making it publick._ + + _I. N._ + +April 1, 1704. + + +Advertisement II + +_In this Second Edition of these Opticks I have omitted the Mathematical +Tracts publish'd at the End of the former Edition, as not belonging to +the Subject. And at the End of the Third Book I have added some +Questions. And to shew that I do not take Gravity for an essential +Property of Bodies, I have added one Question concerning its Cause, +chusing to propose it by way of a Question, because I am not yet +satisfied about it for want of Experiments._ + + _I. N._ + +July 16, 1717. + + +Advertisement to this Fourth Edition + +_This new Edition of Sir_ Isaac Newton's Opticks _is carefully printed +from the Third Edition, as it was corrected by the Author's own Hand, +and left before his Death with the Bookseller. Since Sir_ Isaac's +Lectiones Opticæ, _which he publickly read in the University of_ +Cambridge _in the Years 1669, 1670, and 1671, are lately printed, it has +been thought proper to make at the bottom of the Pages several Citations +from thence, where may be found the Demonstrations, which the Author +omitted in these_ Opticks. + + * * * * * + +Transcriber's Note: There are several greek letters used in the +descriptions of the illustrations. They are signified by [Greek: +letter]. Square roots are noted by the letters sqrt before the equation. + + * * * * * + +THE FIRST BOOK OF OPTICKS + + + + +_PART I._ + + +My Design in this Book is not to explain the Properties of Light by +Hypotheses, but to propose and prove them by Reason and Experiments: In +order to which I shall premise the following Definitions and Axioms. + + + + +_DEFINITIONS_ + + +DEFIN. I. + +_By the Rays of Light I understand its least Parts, and those as well +Successive in the same Lines, as Contemporary in several Lines._ For it +is manifest that Light consists of Parts, both Successive and +Contemporary; because in the same place you may stop that which comes +one moment, and let pass that which comes presently after; and in the +same time you may stop it in any one place, and let it pass in any +other. For that part of Light which is stopp'd cannot be the same with +that which is let pass. The least Light or part of Light, which may be +stopp'd alone without the rest of the Light, or propagated alone, or do +or suffer any thing alone, which the rest of the Light doth not or +suffers not, I call a Ray of Light. + + +DEFIN. II. + +_Refrangibility of the Rays of Light, is their Disposition to be +refracted or turned out of their Way in passing out of one transparent +Body or Medium into another. And a greater or less Refrangibility of +Rays, is their Disposition to be turned more or less out of their Way in +like Incidences on the same Medium._ Mathematicians usually consider the +Rays of Light to be Lines reaching from the luminous Body to the Body +illuminated, and the refraction of those Rays to be the bending or +breaking of those lines in their passing out of one Medium into another. +And thus may Rays and Refractions be considered, if Light be propagated +in an instant. But by an Argument taken from the Æquations of the times +of the Eclipses of _Jupiter's Satellites_, it seems that Light is +propagated in time, spending in its passage from the Sun to us about +seven Minutes of time: And therefore I have chosen to define Rays and +Refractions in such general terms as may agree to Light in both cases. + + +DEFIN. III. + +_Reflexibility of Rays, is their Disposition to be reflected or turned +back into the same Medium from any other Medium upon whose Surface they +fall. And Rays are more or less reflexible, which are turned back more +or less easily._ As if Light pass out of a Glass into Air, and by being +inclined more and more to the common Surface of the Glass and Air, +begins at length to be totally reflected by that Surface; those sorts of +Rays which at like Incidences are reflected most copiously, or by +inclining the Rays begin soonest to be totally reflected, are most +reflexible. + + +DEFIN. IV. + +_The Angle of Incidence is that Angle, which the Line described by the +incident Ray contains with the Perpendicular to the reflecting or +refracting Surface at the Point of Incidence._ + + +DEFIN. V. + +_The Angle of Reflexion or Refraction, is the Angle which the line +described by the reflected or refracted Ray containeth with the +Perpendicular to the reflecting or refracting Surface at the Point of +Incidence._ + + +DEFIN. VI. + +_The Sines of Incidence, Reflexion, and Refraction, are the Sines of the +Angles of Incidence, Reflexion, and Refraction._ + + +DEFIN. VII + +_The Light whose Rays are all alike Refrangible, I call Simple, +Homogeneal and Similar; and that whose Rays are some more Refrangible +than others, I call Compound, Heterogeneal and Dissimilar._ The former +Light I call Homogeneal, not because I would affirm it so in all +respects, but because the Rays which agree in Refrangibility, agree at +least in all those their other Properties which I consider in the +following Discourse. + + +DEFIN. VIII. + +_The Colours of Homogeneal Lights, I call Primary, Homogeneal and +Simple; and those of Heterogeneal Lights, Heterogeneal and Compound._ +For these are always compounded of the colours of Homogeneal Lights; as +will appear in the following Discourse. + + + + +_AXIOMS._ + + +AX. I. + +_The Angles of Reflexion and Refraction, lie in one and the same Plane +with the Angle of Incidence._ + + +AX. II. + +_The Angle of Reflexion is equal to the Angle of Incidence._ + + +AX. III. + +_If the refracted Ray be returned directly back to the Point of +Incidence, it shall be refracted into the Line before described by the +incident Ray._ + + +AX. IV. + +_Refraction out of the rarer Medium into the denser, is made towards the +Perpendicular; that is, so that the Angle of Refraction be less than the +Angle of Incidence._ + + +AX. V. + +_The Sine of Incidence is either accurately or very nearly in a given +Ratio to the Sine of Refraction._ + +Whence if that Proportion be known in any one Inclination of the +incident Ray, 'tis known in all the Inclinations, and thereby the +Refraction in all cases of Incidence on the same refracting Body may be +determined. Thus if the Refraction be made out of Air into Water, the +Sine of Incidence of the red Light is to the Sine of its Refraction as 4 +to 3. If out of Air into Glass, the Sines are as 17 to 11. In Light of +other Colours the Sines have other Proportions: but the difference is so +little that it need seldom be considered. + +[Illustration: FIG. 1] + +Suppose therefore, that RS [in _Fig._ 1.] represents the Surface of +stagnating Water, and that C is the point of Incidence in which any Ray +coming in the Air from A in the Line AC is reflected or refracted, and I +would know whither this Ray shall go after Reflexion or Refraction: I +erect upon the Surface of the Water from the point of Incidence the +Perpendicular CP and produce it downwards to Q, and conclude by the +first Axiom, that the Ray after Reflexion and Refraction, shall be +found somewhere in the Plane of the Angle of Incidence ACP produced. I +let fall therefore upon the Perpendicular CP the Sine of Incidence AD; +and if the reflected Ray be desired, I produce AD to B so that DB be +equal to AD, and draw CB. For this Line CB shall be the reflected Ray; +the Angle of Reflexion BCP and its Sine BD being equal to the Angle and +Sine of Incidence, as they ought to be by the second Axiom, But if the +refracted Ray be desired, I produce AD to H, so that DH may be to AD as +the Sine of Refraction to the Sine of Incidence, that is, (if the Light +be red) as 3 to 4; and about the Center C and in the Plane ACP with the +Radius CA describing a Circle ABE, I draw a parallel to the +Perpendicular CPQ, the Line HE cutting the Circumference in E, and +joining CE, this Line CE shall be the Line of the refracted Ray. For if +EF be let fall perpendicularly on the Line PQ, this Line EF shall be the +Sine of Refraction of the Ray CE, the Angle of Refraction being ECQ; and +this Sine EF is equal to DH, and consequently in Proportion to the Sine +of Incidence AD as 3 to 4. + +In like manner, if there be a Prism of Glass (that is, a Glass bounded +with two Equal and Parallel Triangular ends, and three plain and well +polished Sides, which meet in three Parallel Lines running from the +three Angles of one end to the three Angles of the other end) and if the +Refraction of the Light in passing cross this Prism be desired: Let ACB +[in _Fig._ 2.] represent a Plane cutting this Prism transversly to its +three Parallel lines or edges there where the Light passeth through it, +and let DE be the Ray incident upon the first side of the Prism AC where +the Light goes into the Glass; and by putting the Proportion of the Sine +of Incidence to the Sine of Refraction as 17 to 11 find EF the first +refracted Ray. Then taking this Ray for the Incident Ray upon the second +side of the Glass BC where the Light goes out, find the next refracted +Ray FG by putting the Proportion of the Sine of Incidence to the Sine of +Refraction as 11 to 17. For if the Sine of Incidence out of Air into +Glass be to the Sine of Refraction as 17 to 11, the Sine of Incidence +out of Glass into Air must on the contrary be to the Sine of Refraction +as 11 to 17, by the third Axiom. + +[Illustration: FIG. 2.] + +Much after the same manner, if ACBD [in _Fig._ 3.] represent a Glass +spherically convex on both sides (usually called a _Lens_, such as is a +Burning-glass, or Spectacle-glass, or an Object-glass of a Telescope) +and it be required to know how Light falling upon it from any lucid +point Q shall be refracted, let QM represent a Ray falling upon any +point M of its first spherical Surface ACB, and by erecting a +Perpendicular to the Glass at the point M, find the first refracted Ray +MN by the Proportion of the Sines 17 to 11. Let that Ray in going out of +the Glass be incident upon N, and then find the second refracted Ray +N_q_ by the Proportion of the Sines 11 to 17. And after the same manner +may the Refraction be found when the Lens is convex on one side and +plane or concave on the other, or concave on both sides. + +[Illustration: FIG. 3.] + + +AX. VI. + +_Homogeneal Rays which flow from several Points of any Object, and fall +perpendicularly or almost perpendicularly on any reflecting or +refracting Plane or spherical Surface, shall afterwards diverge from so +many other Points, or be parallel to so many other Lines, or converge to +so many other Points, either accurately or without any sensible Error. +And the same thing will happen, if the Rays be reflected or refracted +successively by two or three or more Plane or Spherical Surfaces._ + +The Point from which Rays diverge or to which they converge may be +called their _Focus_. And the Focus of the incident Rays being given, +that of the reflected or refracted ones may be found by finding the +Refraction of any two Rays, as above; or more readily thus. + +_Cas._ 1. Let ACB [in _Fig._ 4.] be a reflecting or refracting Plane, +and Q the Focus of the incident Rays, and Q_q_C a Perpendicular to that +Plane. And if this Perpendicular be produced to _q_, so that _q_C be +equal to QC, the Point _q_ shall be the Focus of the reflected Rays: Or +if _q_C be taken on the same side of the Plane with QC, and in +proportion to QC as the Sine of Incidence to the Sine of Refraction, the +Point _q_ shall be the Focus of the refracted Rays. + +[Illustration: FIG. 4.] + +_Cas._ 2. Let ACB [in _Fig._ 5.] be the reflecting Surface of any Sphere +whose Centre is E. Bisect any Radius thereof, (suppose EC) in T, and if +in that Radius on the same side the Point T you take the Points Q and +_q_, so that TQ, TE, and T_q_, be continual Proportionals, and the Point +Q be the Focus of the incident Rays, the Point _q_ shall be the Focus of +the reflected ones. + +[Illustration: FIG. 5.] + +_Cas._ 3. Let ACB [in _Fig._ 6.] be the refracting Surface of any Sphere +whose Centre is E. In any Radius thereof EC produced both ways take ET +and C_t_ equal to one another and severally in such Proportion to that +Radius as the lesser of the Sines of Incidence and Refraction hath to +the difference of those Sines. And then if in the same Line you find any +two Points Q and _q_, so that TQ be to ET as E_t_ to _tq_, taking _tq_ +the contrary way from _t_ which TQ lieth from T, and if the Point Q be +the Focus of any incident Rays, the Point _q_ shall be the Focus of the +refracted ones. + +[Illustration: FIG. 6.] + +And by the same means the Focus of the Rays after two or more Reflexions +or Refractions may be found. + +[Illustration: FIG. 7.] + +_Cas._ 4. Let ACBD [in _Fig._ 7.] be any refracting Lens, spherically +Convex or Concave or Plane on either side, and let CD be its Axis (that +is, the Line which cuts both its Surfaces perpendicularly, and passes +through the Centres of the Spheres,) and in this Axis produced let F and +_f_ be the Foci of the refracted Rays found as above, when the incident +Rays on both sides the Lens are parallel to the same Axis; and upon the +Diameter F_f_ bisected in E, describe a Circle. Suppose now that any +Point Q be the Focus of any incident Rays. Draw QE cutting the said +Circle in T and _t_, and therein take _tq_ in such proportion to _t_E as +_t_E or TE hath to TQ. Let _tq_ lie the contrary way from _t_ which TQ +doth from T, and _q_ shall be the Focus of the refracted Rays without +any sensible Error, provided the Point Q be not so remote from the Axis, +nor the Lens so broad as to make any of the Rays fall too obliquely on +the refracting Surfaces.[A] + +And by the like Operations may the reflecting or refracting Surfaces be +found when the two Foci are given, and thereby a Lens be formed, which +shall make the Rays flow towards or from what Place you please.[B] + +So then the Meaning of this Axiom is, that if Rays fall upon any Plane +or Spherical Surface or Lens, and before their Incidence flow from or +towards any Point Q, they shall after Reflexion or Refraction flow from +or towards the Point _q_ found by the foregoing Rules. And if the +incident Rays flow from or towards several points Q, the reflected or +refracted Rays shall flow from or towards so many other Points _q_ +found by the same Rules. Whether the reflected and refracted Rays flow +from or towards the Point _q_ is easily known by the situation of that +Point. For if that Point be on the same side of the reflecting or +refracting Surface or Lens with the Point Q, and the incident Rays flow +from the Point Q, the reflected flow towards the Point _q_ and the +refracted from it; and if the incident Rays flow towards Q, the +reflected flow from _q_, and the refracted towards it. And the contrary +happens when _q_ is on the other side of the Surface. + + +AX. VII. + +_Wherever the Rays which come from all the Points of any Object meet +again in so many Points after they have been made to converge by +Reflection or Refraction, there they will make a Picture of the Object +upon any white Body on which they fall._ + +So if PR [in _Fig._ 3.] represent any Object without Doors, and AB be a +Lens placed at a hole in the Window-shut of a dark Chamber, whereby the +Rays that come from any Point Q of that Object are made to converge and +meet again in the Point _q_; and if a Sheet of white Paper be held at +_q_ for the Light there to fall upon it, the Picture of that Object PR +will appear upon the Paper in its proper shape and Colours. For as the +Light which comes from the Point Q goes to the Point _q_, so the Light +which comes from other Points P and R of the Object, will go to so many +other correspondent Points _p_ and _r_ (as is manifest by the sixth +Axiom;) so that every Point of the Object shall illuminate a +correspondent Point of the Picture, and thereby make a Picture like the +Object in Shape and Colour, this only excepted, that the Picture shall +be inverted. And this is the Reason of that vulgar Experiment of casting +the Species of Objects from abroad upon a Wall or Sheet of white Paper +in a dark Room. + +In like manner, when a Man views any Object PQR, [in _Fig._ 8.] the +Light which comes from the several Points of the Object is so refracted +by the transparent skins and humours of the Eye, (that is, by the +outward coat EFG, called the _Tunica Cornea_, and by the crystalline +humour AB which is beyond the Pupil _mk_) as to converge and meet again +in so many Points in the bottom of the Eye, and there to paint the +Picture of the Object upon that skin (called the _Tunica Retina_) with +which the bottom of the Eye is covered. For Anatomists, when they have +taken off from the bottom of the Eye that outward and most thick Coat +called the _Dura Mater_, can then see through the thinner Coats, the +Pictures of Objects lively painted thereon. And these Pictures, +propagated by Motion along the Fibres of the Optick Nerves into the +Brain, are the cause of Vision. For accordingly as these Pictures are +perfect or imperfect, the Object is seen perfectly or imperfectly. If +the Eye be tinged with any colour (as in the Disease of the _Jaundice_) +so as to tinge the Pictures in the bottom of the Eye with that Colour, +then all Objects appear tinged with the same Colour. If the Humours of +the Eye by old Age decay, so as by shrinking to make the _Cornea_ and +Coat of the _Crystalline Humour_ grow flatter than before, the Light +will not be refracted enough, and for want of a sufficient Refraction +will not converge to the bottom of the Eye but to some place beyond it, +and by consequence paint in the bottom of the Eye a confused Picture, +and according to the Indistinctness of this Picture the Object will +appear confused. This is the reason of the decay of sight in old Men, +and shews why their Sight is mended by Spectacles. For those Convex +glasses supply the defect of plumpness in the Eye, and by increasing the +Refraction make the Rays converge sooner, so as to convene distinctly at +the bottom of the Eye if the Glass have a due degree of convexity. And +the contrary happens in short-sighted Men whose Eyes are too plump. For +the Refraction being now too great, the Rays converge and convene in the +Eyes before they come at the bottom; and therefore the Picture made in +the bottom and the Vision caused thereby will not be distinct, unless +the Object be brought so near the Eye as that the place where the +converging Rays convene may be removed to the bottom, or that the +plumpness of the Eye be taken off and the Refractions diminished by a +Concave-glass of a due degree of Concavity, or lastly that by Age the +Eye grow flatter till it come to a due Figure: For short-sighted Men see +remote Objects best in Old Age, and therefore they are accounted to have +the most lasting Eyes. + +[Illustration: FIG. 8.] + + +AX. VIII. + +_An Object seen by Reflexion or Refraction, appears in that place from +whence the Rays after their last Reflexion or Refraction diverge in +falling on the Spectator's Eye._ + +[Illustration: FIG. 9.] + +If the Object A [in FIG. 9.] be seen by Reflexion of a Looking-glass +_mn_, it shall appear, not in its proper place A, but behind the Glass +at _a_, from whence any Rays AB, AC, AD, which flow from one and the +same Point of the Object, do after their Reflexion made in the Points B, +C, D, diverge in going from the Glass to E, F, G, where they are +incident on the Spectator's Eyes. For these Rays do make the same +Picture in the bottom of the Eyes as if they had come from the Object +really placed at _a_ without the Interposition of the Looking-glass; and +all Vision is made according to the place and shape of that Picture. + +In like manner the Object D [in FIG. 2.] seen through a Prism, appears +not in its proper place D, but is thence translated to some other place +_d_ situated in the last refracted Ray FG drawn backward from F to _d_. + +[Illustration: FIG. 10.] + +And so the Object Q [in FIG. 10.] seen through the Lens AB, appears at +the place _q_ from whence the Rays diverge in passing from the Lens to +the Eye. Now it is to be noted, that the Image of the Object at _q_ is +so much bigger or lesser than the Object it self at Q, as the distance +of the Image at _q_ from the Lens AB is bigger or less than the distance +of the Object at Q from the same Lens. And if the Object be seen through +two or more such Convex or Concave-glasses, every Glass shall make a new +Image, and the Object shall appear in the place of the bigness of the +last Image. Which consideration unfolds the Theory of Microscopes and +Telescopes. For that Theory consists in almost nothing else than the +describing such Glasses as shall make the last Image of any Object as +distinct and large and luminous as it can conveniently be made. + +I have now given in Axioms and their Explications the sum of what hath +hitherto been treated of in Opticks. For what hath been generally +agreed on I content my self to assume under the notion of Principles, in +order to what I have farther to write. And this may suffice for an +Introduction to Readers of quick Wit and good Understanding not yet +versed in Opticks: Although those who are already acquainted with this +Science, and have handled Glasses, will more readily apprehend what +followeth. + +FOOTNOTES: + +[A] In our Author's _Lectiones Opticæ_, Part I. Sect. IV. Prop 29, 30, +there is an elegant Method of determining these _Foci_; not only in +spherical Surfaces, but likewise in any other curved Figure whatever: +And in Prop. 32, 33, the same thing is done for any Ray lying out of the +Axis. + +[B] _Ibid._ Prop. 34. + + + + +_PROPOSITIONS._ + + + +_PROP._ I. THEOR. I. + +_Lights which differ in Colour, differ also in Degrees of +Refrangibility._ + +The PROOF by Experiments. + +_Exper._ 1. + +I took a black oblong stiff Paper terminated by Parallel Sides, and with +a Perpendicular right Line drawn cross from one Side to the other, +distinguished it into two equal Parts. One of these parts I painted with +a red colour and the other with a blue. The Paper was very black, and +the Colours intense and thickly laid on, that the Phænomenon might be +more conspicuous. This Paper I view'd through a Prism of solid Glass, +whose two Sides through which the Light passed to the Eye were plane and +well polished, and contained an Angle of about sixty degrees; which +Angle I call the refracting Angle of the Prism. And whilst I view'd it, +I held it and the Prism before a Window in such manner that the Sides of +the Paper were parallel to the Prism, and both those Sides and the Prism +were parallel to the Horizon, and the cross Line was also parallel to +it: and that the Light which fell from the Window upon the Paper made an +Angle with the Paper, equal to that Angle which was made with the same +Paper by the Light reflected from it to the Eye. Beyond the Prism was +the Wall of the Chamber under the Window covered over with black Cloth, +and the Cloth was involved in Darkness that no Light might be reflected +from thence, which in passing by the Edges of the Paper to the Eye, +might mingle itself with the Light of the Paper, and obscure the +Phænomenon thereof. These things being thus ordered, I found that if the +refracting Angle of the Prism be turned upwards, so that the Paper may +seem to be lifted upwards by the Refraction, its blue half will be +lifted higher by the Refraction than its red half. But if the refracting +Angle of the Prism be turned downward, so that the Paper may seem to be +carried lower by the Refraction, its blue half will be carried something +lower thereby than its red half. Wherefore in both Cases the Light which +comes from the blue half of the Paper through the Prism to the Eye, does +in like Circumstances suffer a greater Refraction than the Light which +comes from the red half, and by consequence is more refrangible. + +_Illustration._ In the eleventh Figure, MN represents the Window, and DE +the Paper terminated with parallel Sides DJ and HE, and by the +transverse Line FG distinguished into two halfs, the one DG of an +intensely blue Colour, the other FE of an intensely red. And BAC_cab_ +represents the Prism whose refracting Planes AB_ba_ and AC_ca_ meet in +the Edge of the refracting Angle A_a_. This Edge A_a_ being upward, is +parallel both to the Horizon, and to the Parallel-Edges of the Paper DJ +and HE, and the transverse Line FG is perpendicular to the Plane of the +Window. And _de_ represents the Image of the Paper seen by Refraction +upwards in such manner, that the blue half DG is carried higher to _dg_ +than the red half FE is to _fe_, and therefore suffers a greater +Refraction. If the Edge of the refracting Angle be turned downward, the +Image of the Paper will be refracted downward; suppose to [Greek: de], +and the blue half will be refracted lower to [Greek: dg] than the red +half is to [Greek: pe]. + +[Illustration: FIG. 11.] + +_Exper._ 2. About the aforesaid Paper, whose two halfs were painted over +with red and blue, and which was stiff like thin Pasteboard, I lapped +several times a slender Thred of very black Silk, in such manner that +the several parts of the Thred might appear upon the Colours like so +many black Lines drawn over them, or like long and slender dark Shadows +cast upon them. I might have drawn black Lines with a Pen, but the +Threds were smaller and better defined. This Paper thus coloured and +lined I set against a Wall perpendicularly to the Horizon, so that one +of the Colours might stand to the Right Hand, and the other to the Left. +Close before the Paper, at the Confine of the Colours below, I placed a +Candle to illuminate the Paper strongly: For the Experiment was tried in +the Night. The Flame of the Candle reached up to the lower edge of the +Paper, or a very little higher. Then at the distance of six Feet, and +one or two Inches from the Paper upon the Floor I erected a Glass Lens +four Inches and a quarter broad, which might collect the Rays coming +from the several Points of the Paper, and make them converge towards so +many other Points at the same distance of six Feet, and one or two +Inches on the other side of the Lens, and so form the Image of the +coloured Paper upon a white Paper placed there, after the same manner +that a Lens at a Hole in a Window casts the Images of Objects abroad +upon a Sheet of white Paper in a dark Room. The aforesaid white Paper, +erected perpendicular to the Horizon, and to the Rays which fell upon it +from the Lens, I moved sometimes towards the Lens, sometimes from it, to +find the Places where the Images of the blue and red Parts of the +coloured Paper appeared most distinct. Those Places I easily knew by the +Images of the black Lines which I had made by winding the Silk about the +Paper. For the Images of those fine and slender Lines (which by reason +of their Blackness were like Shadows on the Colours) were confused and +scarce visible, unless when the Colours on either side of each Line were +terminated most distinctly, Noting therefore, as diligently as I could, +the Places where the Images of the red and blue halfs of the coloured +Paper appeared most distinct, I found that where the red half of the +Paper appeared distinct, the blue half appeared confused, so that the +black Lines drawn upon it could scarce be seen; and on the contrary, +where the blue half appeared most distinct, the red half appeared +confused, so that the black Lines upon it were scarce visible. And +between the two Places where these Images appeared distinct there was +the distance of an Inch and a half; the distance of the white Paper from +the Lens, when the Image of the red half of the coloured Paper appeared +most distinct, being greater by an Inch and an half than the distance of +the same white Paper from the Lens, when the Image of the blue half +appeared most distinct. In like Incidences therefore of the blue and red +upon the Lens, the blue was refracted more by the Lens than the red, so +as to converge sooner by an Inch and a half, and therefore is more +refrangible. + +_Illustration._ In the twelfth Figure (p. 27), DE signifies the coloured +Paper, DG the blue half, FE the red half, MN the Lens, HJ the white +Paper in that Place where the red half with its black Lines appeared +distinct, and _hi_ the same Paper in that Place where the blue half +appeared distinct. The Place _hi_ was nearer to the Lens MN than the +Place HJ by an Inch and an half. + +_Scholium._ The same Things succeed, notwithstanding that some of the +Circumstances be varied; as in the first Experiment when the Prism and +Paper are any ways inclined to the Horizon, and in both when coloured +Lines are drawn upon very black Paper. But in the Description of these +Experiments, I have set down such Circumstances, by which either the +Phænomenon might be render'd more conspicuous, or a Novice might more +easily try them, or by which I did try them only. The same Thing, I have +often done in the following Experiments: Concerning all which, this one +Admonition may suffice. Now from these Experiments it follows not, that +all the Light of the blue is more refrangible than all the Light of the +red: For both Lights are mixed of Rays differently refrangible, so that +in the red there are some Rays not less refrangible than those of the +blue, and in the blue there are some Rays not more refrangible than +those of the red: But these Rays, in proportion to the whole Light, are +but few, and serve to diminish the Event of the Experiment, but are not +able to destroy it. For, if the red and blue Colours were more dilute +and weak, the distance of the Images would be less than an Inch and a +half; and if they were more intense and full, that distance would be +greater, as will appear hereafter. These Experiments may suffice for the +Colours of Natural Bodies. For in the Colours made by the Refraction of +Prisms, this Proposition will appear by the Experiments which are now to +follow in the next Proposition. + + +_PROP._ II. THEOR. II. + +_The Light of the Sun consists of Rays differently Refrangible._ + +The PROOF by Experiments. + +[Illustration: FIG. 12.] + +[Illustration: FIG. 13.] + +_Exper._ 3. + +In a very dark Chamber, at a round Hole, about one third Part of an Inch +broad, made in the Shut of a Window, I placed a Glass Prism, whereby the +Beam of the Sun's Light, which came in at that Hole, might be refracted +upwards toward the opposite Wall of the Chamber, and there form a +colour'd Image of the Sun. The Axis of the Prism (that is, the Line +passing through the middle of the Prism from one end of it to the other +end parallel to the edge of the Refracting Angle) was in this and the +following Experiments perpendicular to the incident Rays. About this +Axis I turned the Prism slowly, and saw the refracted Light on the Wall, +or coloured Image of the Sun, first to descend, and then to ascend. +Between the Descent and Ascent, when the Image seemed Stationary, I +stopp'd the Prism, and fix'd it in that Posture, that it should be moved +no more. For in that Posture the Refractions of the Light at the two +Sides of the refracting Angle, that is, at the Entrance of the Rays into +the Prism, and at their going out of it, were equal to one another.[C] +So also in other Experiments, as often as I would have the Refractions +on both sides the Prism to be equal to one another, I noted the Place +where the Image of the Sun formed by the refracted Light stood still +between its two contrary Motions, in the common Period of its Progress +and Regress; and when the Image fell upon that Place, I made fast the +Prism. And in this Posture, as the most convenient, it is to be +understood that all the Prisms are placed in the following Experiments, +unless where some other Posture is described. The Prism therefore being +placed in this Posture, I let the refracted Light fall perpendicularly +upon a Sheet of white Paper at the opposite Wall of the Chamber, and +observed the Figure and Dimensions of the Solar Image formed on the +Paper by that Light. This Image was Oblong and not Oval, but terminated +with two Rectilinear and Parallel Sides, and two Semicircular Ends. On +its Sides it was bounded pretty distinctly, but on its Ends very +confusedly and indistinctly, the Light there decaying and vanishing by +degrees. The Breadth of this Image answered to the Sun's Diameter, and +was about two Inches and the eighth Part of an Inch, including the +Penumbra. For the Image was eighteen Feet and an half distant from the +Prism, and at this distance that Breadth, if diminished by the Diameter +of the Hole in the Window-shut, that is by a quarter of an Inch, +subtended an Angle at the Prism of about half a Degree, which is the +Sun's apparent Diameter. But the Length of the Image was about ten +Inches and a quarter, and the Length of the Rectilinear Sides about +eight Inches; and the refracting Angle of the Prism, whereby so great a +Length was made, was 64 degrees. With a less Angle the Length of the +Image was less, the Breadth remaining the same. If the Prism was turned +about its Axis that way which made the Rays emerge more obliquely out of +the second refracting Surface of the Prism, the Image soon became an +Inch or two longer, or more; and if the Prism was turned about the +contrary way, so as to make the Rays fall more obliquely on the first +refracting Surface, the Image soon became an Inch or two shorter. And +therefore in trying this Experiment, I was as curious as I could be in +placing the Prism by the above-mention'd Rule exactly in such a Posture, +that the Refractions of the Rays at their Emergence out of the Prism +might be equal to that at their Incidence on it. This Prism had some +Veins running along within the Glass from one end to the other, which +scattered some of the Sun's Light irregularly, but had no sensible +Effect in increasing the Length of the coloured Spectrum. For I tried +the same Experiment with other Prisms with the same Success. And +particularly with a Prism which seemed free from such Veins, and whose +refracting Angle was 62-1/2 Degrees, I found the Length of the Image +9-3/4 or 10 Inches at the distance of 18-1/2 Feet from the Prism, the +Breadth of the Hole in the Window-shut being 1/4 of an Inch, as before. +And because it is easy to commit a Mistake in placing the Prism in its +due Posture, I repeated the Experiment four or five Times, and always +found the Length of the Image that which is set down above. With another +Prism of clearer Glass and better Polish, which seemed free from Veins, +and whose refracting Angle was 63-1/2 Degrees, the Length of this Image +at the same distance of 18-1/2 Feet was also about 10 Inches, or 10-1/8. +Beyond these Measures for about a 1/4 or 1/3 of an Inch at either end of +the Spectrum the Light of the Clouds seemed to be a little tinged with +red and violet, but so very faintly, that I suspected that Tincture +might either wholly, or in great Measure arise from some Rays of the +Spectrum scattered irregularly by some Inequalities in the Substance and +Polish of the Glass, and therefore I did not include it in these +Measures. Now the different Magnitude of the hole in the Window-shut, +and different thickness of the Prism where the Rays passed through it, +and different inclinations of the Prism to the Horizon, made no sensible +changes in the length of the Image. Neither did the different matter of +the Prisms make any: for in a Vessel made of polished Plates of Glass +cemented together in the shape of a Prism and filled with Water, there +is the like Success of the Experiment according to the quantity of the +Refraction. It is farther to be observed, that the Rays went on in right +Lines from the Prism to the Image, and therefore at their very going out +of the Prism had all that Inclination to one another from which the +length of the Image proceeded, that is, the Inclination of more than two +degrees and an half. And yet according to the Laws of Opticks vulgarly +received, they could not possibly be so much inclined to one another.[D] +For let EG [_Fig._ 13. (p. 27)] represent the Window-shut, F the hole +made therein through which a beam of the Sun's Light was transmitted +into the darkened Chamber, and ABC a Triangular Imaginary Plane whereby +the Prism is feigned to be cut transversely through the middle of the +Light. Or if you please, let ABC represent the Prism it self, looking +directly towards the Spectator's Eye with its nearer end: And let XY be +the Sun, MN the Paper upon which the Solar Image or Spectrum is cast, +and PT the Image it self whose sides towards _v_ and _w_ are Rectilinear +and Parallel, and ends towards P and T Semicircular. YKHP and XLJT are +two Rays, the first of which comes from the lower part of the Sun to the +higher part of the Image, and is refracted in the Prism at K and H, and +the latter comes from the higher part of the Sun to the lower part of +the Image, and is refracted at L and J. Since the Refractions on both +sides the Prism are equal to one another, that is, the Refraction at K +equal to the Refraction at J, and the Refraction at L equal to the +Refraction at H, so that the Refractions of the incident Rays at K and L +taken together, are equal to the Refractions of the emergent Rays at H +and J taken together: it follows by adding equal things to equal things, +that the Refractions at K and H taken together, are equal to the +Refractions at J and L taken together, and therefore the two Rays being +equally refracted, have the same Inclination to one another after +Refraction which they had before; that is, the Inclination of half a +Degree answering to the Sun's Diameter. For so great was the inclination +of the Rays to one another before Refraction. So then, the length of the +Image PT would by the Rules of Vulgar Opticks subtend an Angle of half a +Degree at the Prism, and by Consequence be equal to the breadth _vw_; +and therefore the Image would be round. Thus it would be were the two +Rays XLJT and YKHP, and all the rest which form the Image P_w_T_v_, +alike refrangible. And therefore seeing by Experience it is found that +the Image is not round, but about five times longer than broad, the Rays +which going to the upper end P of the Image suffer the greatest +Refraction, must be more refrangible than those which go to the lower +end T, unless the Inequality of Refraction be casual. + +This Image or Spectrum PT was coloured, being red at its least refracted +end T, and violet at its most refracted end P, and yellow green and +blue in the intermediate Spaces. Which agrees with the first +Proposition, that Lights which differ in Colour, do also differ in +Refrangibility. The length of the Image in the foregoing Experiments, I +measured from the faintest and outmost red at one end, to the faintest +and outmost blue at the other end, excepting only a little Penumbra, +whose breadth scarce exceeded a quarter of an Inch, as was said above. + +_Exper._ 4. In the Sun's Beam which was propagated into the Room through +the hole in the Window-shut, at the distance of some Feet from the hole, +I held the Prism in such a Posture, that its Axis might be perpendicular +to that Beam. Then I looked through the Prism upon the hole, and turning +the Prism to and fro about its Axis, to make the Image of the Hole +ascend and descend, when between its two contrary Motions it seemed +Stationary, I stopp'd the Prism, that the Refractions of both sides of +the refracting Angle might be equal to each other, as in the former +Experiment. In this situation of the Prism viewing through it the said +Hole, I observed the length of its refracted Image to be many times +greater than its breadth, and that the most refracted part thereof +appeared violet, the least refracted red, the middle parts blue, green +and yellow in order. The same thing happen'd when I removed the Prism +out of the Sun's Light, and looked through it upon the hole shining by +the Light of the Clouds beyond it. And yet if the Refraction were done +regularly according to one certain Proportion of the Sines of Incidence +and Refraction as is vulgarly supposed, the refracted Image ought to +have appeared round. + +So then, by these two Experiments it appears, that in Equal Incidences +there is a considerable inequality of Refractions. But whence this +inequality arises, whether it be that some of the incident Rays are +refracted more, and others less, constantly, or by chance, or that one +and the same Ray is by Refraction disturbed, shatter'd, dilated, and as +it were split and spread into many diverging Rays, as _Grimaldo_ +supposes, does not yet appear by these Experiments, but will appear by +those that follow. + +_Exper._ 5. Considering therefore, that if in the third Experiment the +Image of the Sun should be drawn out into an oblong Form, either by a +Dilatation of every Ray, or by any other casual inequality of the +Refractions, the same oblong Image would by a second Refraction made +sideways be drawn out as much in breadth by the like Dilatation of the +Rays, or other casual inequality of the Refractions sideways, I tried +what would be the Effects of such a second Refraction. For this end I +ordered all things as in the third Experiment, and then placed a second +Prism immediately after the first in a cross Position to it, that it +might again refract the beam of the Sun's Light which came to it through +the first Prism. In the first Prism this beam was refracted upwards, and +in the second sideways. And I found that by the Refraction of the second +Prism, the breadth of the Image was not increased, but its superior +part, which in the first Prism suffered the greater Refraction, and +appeared violet and blue, did again in the second Prism suffer a greater +Refraction than its inferior part, which appeared red and yellow, and +this without any Dilatation of the Image in breadth. + +[Illustration: FIG. 14] + +_Illustration._ Let S [_Fig._ 14, 15.] represent the Sun, F the hole in +the Window, ABC the first Prism, DH the second Prism, Y the round Image +of the Sun made by a direct beam of Light when the Prisms are taken +away, PT the oblong Image of the Sun made by that beam passing through +the first Prism alone, when the second Prism is taken away, and _pt_ the +Image made by the cross Refractions of both Prisms together. Now if the +Rays which tend towards the several Points of the round Image Y were +dilated and spread by the Refraction of the first Prism, so that they +should not any longer go in single Lines to single Points, but that +every Ray being split, shattered, and changed from a Linear Ray to a +Superficies of Rays diverging from the Point of Refraction, and lying in +the Plane of the Angles of Incidence and Refraction, they should go in +those Planes to so many Lines reaching almost from one end of the Image +PT to the other, and if that Image should thence become oblong: those +Rays and their several parts tending towards the several Points of the +Image PT ought to be again dilated and spread sideways by the transverse +Refraction of the second Prism, so as to compose a four square Image, +such as is represented at [Greek: pt]. For the better understanding of +which, let the Image PT be distinguished into five equal parts PQK, +KQRL, LRSM, MSVN, NVT. And by the same irregularity that the orbicular +Light Y is by the Refraction of the first Prism dilated and drawn out +into a long Image PT, the Light PQK which takes up a space of the same +length and breadth with the Light Y ought to be by the Refraction of the +second Prism dilated and drawn out into the long Image _[Greek: p]qkp_, +and the Light KQRL into the long Image _kqrl_, and the Lights LRSM, +MSVN, NVT, into so many other long Images _lrsm_, _msvn_, _nvt[Greek: +t]_; and all these long Images would compose the four square Images +_[Greek: pt]_. Thus it ought to be were every Ray dilated by Refraction, +and spread into a triangular Superficies of Rays diverging from the +Point of Refraction. For the second Refraction would spread the Rays one +way as much as the first doth another, and so dilate the Image in +breadth as much as the first doth in length. And the same thing ought to +happen, were some rays casually refracted more than others. But the +Event is otherwise. The Image PT was not made broader by the Refraction +of the second Prism, but only became oblique, as 'tis represented at +_pt_, its upper end P being by the Refraction translated to a greater +distance than its lower end T. So then the Light which went towards the +upper end P of the Image, was (at equal Incidences) more refracted in +the second Prism, than the Light which tended towards the lower end T, +that is the blue and violet, than the red and yellow; and therefore was +more refrangible. The same Light was by the Refraction of the first +Prism translated farther from the place Y to which it tended before +Refraction; and therefore suffered as well in the first Prism as in the +second a greater Refraction than the rest of the Light, and by +consequence was more refrangible than the rest, even before its +incidence on the first Prism. + +Sometimes I placed a third Prism after the second, and sometimes also a +fourth after the third, by all which the Image might be often refracted +sideways: but the Rays which were more refracted than the rest in the +first Prism were also more refracted in all the rest, and that without +any Dilatation of the Image sideways: and therefore those Rays for their +constancy of a greater Refraction are deservedly reputed more +refrangible. + +[Illustration: FIG. 15] + +But that the meaning of this Experiment may more clearly appear, it is +to be considered that the Rays which are equally refrangible do fall +upon a Circle answering to the Sun's Disque. For this was proved in the +third Experiment. By a Circle I understand not here a perfect +geometrical Circle, but any orbicular Figure whose length is equal to +its breadth, and which, as to Sense, may seem circular. Let therefore AG +[in _Fig._ 15.] represent the Circle which all the most refrangible Rays +propagated from the whole Disque of the Sun, would illuminate and paint +upon the opposite Wall if they were alone; EL the Circle which all the +least refrangible Rays would in like manner illuminate and paint if they +were alone; BH, CJ, DK, the Circles which so many intermediate sorts of +Rays would successively paint upon the Wall, if they were singly +propagated from the Sun in successive order, the rest being always +intercepted; and conceive that there are other intermediate Circles +without Number, which innumerable other intermediate sorts of Rays would +successively paint upon the Wall if the Sun should successively emit +every sort apart. And seeing the Sun emits all these sorts at once, they +must all together illuminate and paint innumerable equal Circles, of all +which, being according to their degrees of Refrangibility placed in +order in a continual Series, that oblong Spectrum PT is composed which I +described in the third Experiment. Now if the Sun's circular Image Y [in +_Fig._ 15.] which is made by an unrefracted beam of Light was by any +Dilation of the single Rays, or by any other irregularity in the +Refraction of the first Prism, converted into the oblong Spectrum, PT: +then ought every Circle AG, BH, CJ, &c. in that Spectrum, by the cross +Refraction of the second Prism again dilating or otherwise scattering +the Rays as before, to be in like manner drawn out and transformed into +an oblong Figure, and thereby the breadth of the Image PT would be now +as much augmented as the length of the Image Y was before by the +Refraction of the first Prism; and thus by the Refractions of both +Prisms together would be formed a four square Figure _p[Greek: +p]t[Greek: t]_, as I described above. Wherefore since the breadth of the +Spectrum PT is not increased by the Refraction sideways, it is certain +that the Rays are not split or dilated, or otherways irregularly +scatter'd by that Refraction, but that every Circle is by a regular and +uniform Refraction translated entire into another Place, as the Circle +AG by the greatest Refraction into the place _ag_, the Circle BH by a +less Refraction into the place _bh_, the Circle CJ by a Refraction still +less into the place _ci_, and so of the rest; by which means a new +Spectrum _pt_ inclined to the former PT is in like manner composed of +Circles lying in a right Line; and these Circles must be of the same +bigness with the former, because the breadths of all the Spectrums Y, PT +and _pt_ at equal distances from the Prisms are equal. + +I considered farther, that by the breadth of the hole F through which +the Light enters into the dark Chamber, there is a Penumbra made in the +Circuit of the Spectrum Y, and that Penumbra remains in the rectilinear +Sides of the Spectrums PT and _pt_. I placed therefore at that hole a +Lens or Object-glass of a Telescope which might cast the Image of the +Sun distinctly on Y without any Penumbra at all, and found that the +Penumbra of the rectilinear Sides of the oblong Spectrums PT and _pt_ +was also thereby taken away, so that those Sides appeared as distinctly +defined as did the Circumference of the first Image Y. Thus it happens +if the Glass of the Prisms be free from Veins, and their sides be +accurately plane and well polished without those numberless Waves or +Curles which usually arise from Sand-holes a little smoothed in +polishing with Putty. If the Glass be only well polished and free from +Veins, and the Sides not accurately plane, but a little Convex or +Concave, as it frequently happens; yet may the three Spectrums Y, PT and +_pt_ want Penumbras, but not in equal distances from the Prisms. Now +from this want of Penumbras, I knew more certainly that every one of the +Circles was refracted according to some most regular, uniform and +constant Law. For if there were any irregularity in the Refraction, the +right Lines AE and GL, which all the Circles in the Spectrum PT do +touch, could not by that Refraction be translated into the Lines _ae_ +and _gl_ as distinct and straight as they were before, but there would +arise in those translated Lines some Penumbra or Crookedness or +Undulation, or other sensible Perturbation contrary to what is found by +Experience. Whatsoever Penumbra or Perturbation should be made in the +Circles by the cross Refraction of the second Prism, all that Penumbra +or Perturbation would be conspicuous in the right Lines _ae_ and _gl_ +which touch those Circles. And therefore since there is no such Penumbra +or Perturbation in those right Lines, there must be none in the +Circles. Since the distance between those Tangents or breadth of the +Spectrum is not increased by the Refractions, the Diameters of the +Circles are not increased thereby. Since those Tangents continue to be +right Lines, every Circle which in the first Prism is more or less +refracted, is exactly in the same proportion more or less refracted in +the second. And seeing all these things continue to succeed after the +same manner when the Rays are again in a third Prism, and again in a +fourth refracted sideways, it is evident that the Rays of one and the +same Circle, as to their degree of Refrangibility, continue always +uniform and homogeneal to one another, and that those of several Circles +do differ in degree of Refrangibility, and that in some certain and +constant Proportion. Which is the thing I was to prove. + +There is yet another Circumstance or two of this Experiment by which it +becomes still more plain and convincing. Let the second Prism DH [in +_Fig._ 16.] be placed not immediately after the first, but at some +distance from it; suppose in the mid-way between it and the Wall on +which the oblong Spectrum PT is cast, so that the Light from the first +Prism may fall upon it in the form of an oblong Spectrum [Greek: pt] +parallel to this second Prism, and be refracted sideways to form the +oblong Spectrum _pt_ upon the Wall. And you will find as before, that +this Spectrum _pt_ is inclined to that Spectrum PT, which the first +Prism forms alone without the second; the blue ends P and _p_ being +farther distant from one another than the red ones T and _t_, and by +consequence that the Rays which go to the blue end [Greek: p] of the +Image [Greek: pt], and which therefore suffer the greatest Refraction in +the first Prism, are again in the second Prism more refracted than the +rest. + +[Illustration: FIG. 16.] + +[Illustration: FIG. 17.] + +The same thing I try'd also by letting the Sun's Light into a dark Room +through two little round holes F and [Greek: ph] [in _Fig._ 17.] made in +the Window, and with two parallel Prisms ABC and [Greek: abg] placed at +those holes (one at each) refracting those two beams of Light to the +opposite Wall of the Chamber, in such manner that the two colour'd +Images PT and MN which they there painted were joined end to end and lay +in one straight Line, the red end T of the one touching the blue end M +of the other. For if these two refracted Beams were again by a third +Prism DH placed cross to the two first, refracted sideways, and the +Spectrums thereby translated to some other part of the Wall of the +Chamber, suppose the Spectrum PT to _pt_ and the Spectrum MN to _mn_, +these translated Spectrums _pt_ and _mn_ would not lie in one straight +Line with their ends contiguous as before, but be broken off from one +another and become parallel, the blue end _m_ of the Image _mn_ being by +a greater Refraction translated farther from its former place MT, than +the red end _t_ of the other Image _pt_ from the same place MT; which +puts the Proposition past Dispute. And this happens whether the third +Prism DH be placed immediately after the two first, or at a great +distance from them, so that the Light refracted in the two first Prisms +be either white and circular, or coloured and oblong when it falls on +the third. + +_Exper._ 6. In the middle of two thin Boards I made round holes a third +part of an Inch in diameter, and in the Window-shut a much broader hole +being made to let into my darkned Chamber a large Beam of the Sun's +Light; I placed a Prism behind the Shut in that beam to refract it +towards the opposite Wall, and close behind the Prism I fixed one of the +Boards, in such manner that the middle of the refracted Light might pass +through the hole made in it, and the rest be intercepted by the Board. +Then at the distance of about twelve Feet from the first Board I fixed +the other Board in such manner that the middle of the refracted Light +which came through the hole in the first Board, and fell upon the +opposite Wall, might pass through the hole in this other Board, and the +rest being intercepted by the Board might paint upon it the coloured +Spectrum of the Sun. And close behind this Board I fixed another Prism +to refract the Light which came through the hole. Then I returned +speedily to the first Prism, and by turning it slowly to and fro about +its Axis, I caused the Image which fell upon the second Board to move up +and down upon that Board, that all its parts might successively pass +through the hole in that Board and fall upon the Prism behind it. And in +the mean time, I noted the places on the opposite Wall to which that +Light after its Refraction in the second Prism did pass; and by the +difference of the places I found that the Light which being most +refracted in the first Prism did go to the blue end of the Image, was +again more refracted in the second Prism than the Light which went to +the red end of that Image, which proves as well the first Proposition as +the second. And this happened whether the Axis of the two Prisms were +parallel, or inclined to one another, and to the Horizon in any given +Angles. + +_Illustration._ Let F [in _Fig._ 18.] be the wide hole in the +Window-shut, through which the Sun shines upon the first Prism ABC, and +let the refracted Light fall upon the middle of the Board DE, and the +middle part of that Light upon the hole G made in the middle part of +that Board. Let this trajected part of that Light fall again upon the +middle of the second Board _de_, and there paint such an oblong coloured +Image of the Sun as was described in the third Experiment. By turning +the Prism ABC slowly to and fro about its Axis, this Image will be made +to move up and down the Board _de_, and by this means all its parts from +one end to the other may be made to pass successively through the hole +_g_ which is made in the middle of that Board. In the mean while another +Prism _abc_ is to be fixed next after that hole _g_, to refract the +trajected Light a second time. And these things being thus ordered, I +marked the places M and N of the opposite Wall upon which the refracted +Light fell, and found that whilst the two Boards and second Prism +remained unmoved, those places by turning the first Prism about its Axis +were changed perpetually. For when the lower part of the Light which +fell upon the second Board _de_ was cast through the hole _g_, it went +to a lower place M on the Wall and when the higher part of that Light +was cast through the same hole _g_, it went to a higher place N on the +Wall, and when any intermediate part of the Light was cast through that +hole, it went to some place on the Wall between M and N. The unchanged +Position of the holes in the Boards, made the Incidence of the Rays upon +the second Prism to be the same in all cases. And yet in that common +Incidence some of the Rays were more refracted, and others less. And +those were more refracted in this Prism, which by a greater Refraction +in the first Prism were more turned out of the way, and therefore for +their Constancy of being more refracted are deservedly called more +refrangible. + +[Illustration: FIG. 18.] + +[Illustration: FIG. 20.] + +_Exper._ 7. At two holes made near one another in my Window-shut I +placed two Prisms, one at each, which might cast upon the opposite Wall +(after the manner of the third Experiment) two oblong coloured Images of +the Sun. And at a little distance from the Wall I placed a long slender +Paper with straight and parallel edges, and ordered the Prisms and Paper +so, that the red Colour of one Image might fall directly upon one half +of the Paper, and the violet Colour of the other Image upon the other +half of the same Paper; so that the Paper appeared of two Colours, red +and violet, much after the manner of the painted Paper in the first and +second Experiments. Then with a black Cloth I covered the Wall behind +the Paper, that no Light might be reflected from it to disturb the +Experiment, and viewing the Paper through a third Prism held parallel +to it, I saw that half of it which was illuminated by the violet Light +to be divided from the other half by a greater Refraction, especially +when I went a good way off from the Paper. For when I viewed it too near +at hand, the two halfs of the Paper did not appear fully divided from +one another, but seemed contiguous at one of their Angles like the +painted Paper in the first Experiment. Which also happened when the +Paper was too broad. + +[Illustration: FIG. 19.] + +Sometimes instead of the Paper I used a white Thred, and this appeared +through the Prism divided into two parallel Threds as is represented in +the nineteenth Figure, where DG denotes the Thred illuminated with +violet Light from D to E and with red Light from F to G, and _defg_ are +the parts of the Thred seen by Refraction. If one half of the Thred be +constantly illuminated with red, and the other half be illuminated with +all the Colours successively, (which may be done by causing one of the +Prisms to be turned about its Axis whilst the other remains unmoved) +this other half in viewing the Thred through the Prism, will appear in +a continual right Line with the first half when illuminated with red, +and begin to be a little divided from it when illuminated with Orange, +and remove farther from it when illuminated with yellow, and still +farther when with green, and farther when with blue, and go yet farther +off when illuminated with Indigo, and farthest when with deep violet. +Which plainly shews, that the Lights of several Colours are more and +more refrangible one than another, in this Order of their Colours, red, +orange, yellow, green, blue, indigo, deep violet; and so proves as well +the first Proposition as the second. + +I caused also the coloured Spectrums PT [in _Fig._ 17.] and MN made in a +dark Chamber by the Refractions of two Prisms to lie in a Right Line end +to end, as was described above in the fifth Experiment, and viewing them +through a third Prism held parallel to their Length, they appeared no +longer in a Right Line, but became broken from one another, as they are +represented at _pt_ and _mn_, the violet end _m_ of the Spectrum _mn_ +being by a greater Refraction translated farther from its former Place +MT than the red end _t_ of the other Spectrum _pt_. + +I farther caused those two Spectrums PT [in _Fig._ 20.] and MN to become +co-incident in an inverted Order of their Colours, the red end of each +falling on the violet end of the other, as they are represented in the +oblong Figure PTMN; and then viewing them through a Prism DH held +parallel to their Length, they appeared not co-incident, as when view'd +with the naked Eye, but in the form of two distinct Spectrums _pt_ and +_mn_ crossing one another in the middle after the manner of the Letter +X. Which shews that the red of the one Spectrum and violet of the other, +which were co-incident at PN and MT, being parted from one another by a +greater Refraction of the violet to _p_ and _m_ than of the red to _n_ +and _t_, do differ in degrees of Refrangibility. + +I illuminated also a little Circular Piece of white Paper all over with +the Lights of both Prisms intermixed, and when it was illuminated with +the red of one Spectrum, and deep violet of the other, so as by the +Mixture of those Colours to appear all over purple, I viewed the Paper, +first at a less distance, and then at a greater, through a third Prism; +and as I went from the Paper, the refracted Image thereof became more +and more divided by the unequal Refraction of the two mixed Colours, and +at length parted into two distinct Images, a red one and a violet one, +whereof the violet was farthest from the Paper, and therefore suffered +the greatest Refraction. And when that Prism at the Window, which cast +the violet on the Paper was taken away, the violet Image disappeared; +but when the other Prism was taken away the red vanished; which shews, +that these two Images were nothing else than the Lights of the two +Prisms, which had been intermixed on the purple Paper, but were parted +again by their unequal Refractions made in the third Prism, through +which the Paper was view'd. This also was observable, that if one of the +Prisms at the Window, suppose that which cast the violet on the Paper, +was turned about its Axis to make all the Colours in this order, +violet, indigo, blue, green, yellow, orange, red, fall successively on +the Paper from that Prism, the violet Image changed Colour accordingly, +turning successively to indigo, blue, green, yellow and red, and in +changing Colour came nearer and nearer to the red Image made by the +other Prism, until when it was also red both Images became fully +co-incident. + +I placed also two Paper Circles very near one another, the one in the +red Light of one Prism, and the other in the violet Light of the other. +The Circles were each of them an Inch in diameter, and behind them the +Wall was dark, that the Experiment might not be disturbed by any Light +coming from thence. These Circles thus illuminated, I viewed through a +Prism, so held, that the Refraction might be made towards the red +Circle, and as I went from them they came nearer and nearer together, +and at length became co-incident; and afterwards when I went still +farther off, they parted again in a contrary Order, the violet by a +greater Refraction being carried beyond the red. + +_Exper._ 8. In Summer, when the Sun's Light uses to be strongest, I +placed a Prism at the Hole of the Window-shut, as in the third +Experiment, yet so that its Axis might be parallel to the Axis of the +World, and at the opposite Wall in the Sun's refracted Light, I placed +an open Book. Then going six Feet and two Inches from the Book, I placed +there the above-mentioned Lens, by which the Light reflected from the +Book might be made to converge and meet again at the distance of six +Feet and two Inches behind the Lens, and there paint the Species of the +Book upon a Sheet of white Paper much after the manner of the second +Experiment. The Book and Lens being made fast, I noted the Place where +the Paper was, when the Letters of the Book, illuminated by the fullest +red Light of the Solar Image falling upon it, did cast their Species on +that Paper most distinctly: And then I stay'd till by the Motion of the +Sun, and consequent Motion of his Image on the Book, all the Colours +from that red to the middle of the blue pass'd over those Letters; and +when those Letters were illuminated by that blue, I noted again the +Place of the Paper when they cast their Species most distinctly upon it: +And I found that this last Place of the Paper was nearer to the Lens +than its former Place by about two Inches and an half, or two and three +quarters. So much sooner therefore did the Light in the violet end of +the Image by a greater Refraction converge and meet, than the Light in +the red end. But in trying this, the Chamber was as dark as I could make +it. For, if these Colours be diluted and weakned by the Mixture of any +adventitious Light, the distance between the Places of the Paper will +not be so great. This distance in the second Experiment, where the +Colours of natural Bodies were made use of, was but an Inch and an half, +by reason of the Imperfection of those Colours. Here in the Colours of +the Prism, which are manifestly more full, intense, and lively than +those of natural Bodies, the distance is two Inches and three quarters. +And were the Colours still more full, I question not but that the +distance would be considerably greater. For the coloured Light of the +Prism, by the interfering of the Circles described in the second Figure +of the fifth Experiment, and also by the Light of the very bright Clouds +next the Sun's Body intermixing with these Colours, and by the Light +scattered by the Inequalities in the Polish of the Prism, was so very +much compounded, that the Species which those faint and dark Colours, +the indigo and violet, cast upon the Paper were not distinct enough to +be well observed. + +_Exper._ 9. A Prism, whose two Angles at its Base were equal to one +another, and half right ones, and the third a right one, I placed in a +Beam of the Sun's Light let into a dark Chamber through a Hole in the +Window-shut, as in the third Experiment. And turning the Prism slowly +about its Axis, until all the Light which went through one of its +Angles, and was refracted by it began to be reflected by its Base, at +which till then it went out of the Glass, I observed that those Rays +which had suffered the greatest Refraction were sooner reflected than +the rest. I conceived therefore, that those Rays of the reflected Light, +which were most refrangible, did first of all by a total Reflexion +become more copious in that Light than the rest, and that afterwards the +rest also, by a total Reflexion, became as copious as these. To try +this, I made the reflected Light pass through another Prism, and being +refracted by it to fall afterwards upon a Sheet of white Paper placed +at some distance behind it, and there by that Refraction to paint the +usual Colours of the Prism. And then causing the first Prism to be +turned about its Axis as above, I observed that when those Rays, which +in this Prism had suffered the greatest Refraction, and appeared of a +blue and violet Colour began to be totally reflected, the blue and +violet Light on the Paper, which was most refracted in the second Prism, +received a sensible Increase above that of the red and yellow, which was +least refracted; and afterwards, when the rest of the Light which was +green, yellow, and red, began to be totally reflected in the first +Prism, the Light of those Colours on the Paper received as great an +Increase as the violet and blue had done before. Whence 'tis manifest, +that the Beam of Light reflected by the Base of the Prism, being +augmented first by the more refrangible Rays, and afterwards by the less +refrangible ones, is compounded of Rays differently refrangible. And +that all such reflected Light is of the same Nature with the Sun's Light +before its Incidence on the Base of the Prism, no Man ever doubted; it +being generally allowed, that Light by such Reflexions suffers no +Alteration in its Modifications and Properties. I do not here take +Notice of any Refractions made in the sides of the first Prism, because +the Light enters it perpendicularly at the first side, and goes out +perpendicularly at the second side, and therefore suffers none. So then, +the Sun's incident Light being of the same Temper and Constitution with +his emergent Light, and the last being compounded of Rays differently +refrangible, the first must be in like manner compounded. + +[Illustration: FIG. 21.] + +_Illustration._ In the twenty-first Figure, ABC is the first Prism, BC +its Base, B and C its equal Angles at the Base, each of 45 Degrees, A +its rectangular Vertex, FM a beam of the Sun's Light let into a dark +Room through a hole F one third part of an Inch broad, M its Incidence +on the Base of the Prism, MG a less refracted Ray, MH a more refracted +Ray, MN the beam of Light reflected from the Base, VXY the second Prism +by which this beam in passing through it is refracted, N_t_ the less +refracted Light of this beam, and N_p_ the more refracted part thereof. +When the first Prism ABC is turned about its Axis according to the order +of the Letters ABC, the Rays MH emerge more and more obliquely out of +that Prism, and at length after their most oblique Emergence are +reflected towards N, and going on to _p_ do increase the Number of the +Rays N_p_. Afterwards by continuing the Motion of the first Prism, the +Rays MG are also reflected to N and increase the number of the Rays +N_t_. And therefore the Light MN admits into its Composition, first the +more refrangible Rays, and then the less refrangible Rays, and yet after +this Composition is of the same Nature with the Sun's immediate Light +FM, the Reflexion of the specular Base BC causing no Alteration therein. + +_Exper._ 10. Two Prisms, which were alike in Shape, I tied so together, +that their Axis and opposite Sides being parallel, they composed a +Parallelopiped. And, the Sun shining into my dark Chamber through a +little hole in the Window-shut, I placed that Parallelopiped in his beam +at some distance from the hole, in such a Posture, that the Axes of the +Prisms might be perpendicular to the incident Rays, and that those Rays +being incident upon the first Side of one Prism, might go on through the +two contiguous Sides of both Prisms, and emerge out of the last Side of +the second Prism. This Side being parallel to the first Side of the +first Prism, caused the emerging Light to be parallel to the incident. +Then, beyond these two Prisms I placed a third, which might refract that +emergent Light, and by that Refraction cast the usual Colours of the +Prism upon the opposite Wall, or upon a sheet of white Paper held at a +convenient Distance behind the Prism for that refracted Light to fall +upon it. After this I turned the Parallelopiped about its Axis, and +found that when the contiguous Sides of the two Prisms became so oblique +to the incident Rays, that those Rays began all of them to be +reflected, those Rays which in the third Prism had suffered the greatest +Refraction, and painted the Paper with violet and blue, were first of +all by a total Reflexion taken out of the transmitted Light, the rest +remaining and on the Paper painting their Colours of green, yellow, +orange and red, as before; and afterwards by continuing the Motion of +the two Prisms, the rest of the Rays also by a total Reflexion vanished +in order, according to their degrees of Refrangibility. The Light +therefore which emerged out of the two Prisms is compounded of Rays +differently refrangible, seeing the more refrangible Rays may be taken +out of it, while the less refrangible remain. But this Light being +trajected only through the parallel Superficies of the two Prisms, if it +suffer'd any change by the Refraction of one Superficies it lost that +Impression by the contrary Refraction of the other Superficies, and so +being restor'd to its pristine Constitution, became of the same Nature +and Condition as at first before its Incidence on those Prisms; and +therefore, before its Incidence, was as much compounded of Rays +differently refrangible, as afterwards. + +[Illustration: FIG. 22.] + +_Illustration._ In the twenty second Figure ABC and BCD are the two +Prisms tied together in the form of a Parallelopiped, their Sides BC and +CB being contiguous, and their Sides AB and CD parallel. And HJK is the +third Prism, by which the Sun's Light propagated through the hole F into +the dark Chamber, and there passing through those sides of the Prisms +AB, BC, CB and CD, is refracted at O to the white Paper PT, falling +there partly upon P by a greater Refraction, partly upon T by a less +Refraction, and partly upon R and other intermediate places by +intermediate Refractions. By turning the Parallelopiped ACBD about its +Axis, according to the order of the Letters A, C, D, B, at length when +the contiguous Planes BC and CB become sufficiently oblique to the Rays +FM, which are incident upon them at M, there will vanish totally out of +the refracted Light OPT, first of all the most refracted Rays OP, (the +rest OR and OT remaining as before) then the Rays OR and other +intermediate ones, and lastly, the least refracted Rays OT. For when +the Plane BC becomes sufficiently oblique to the Rays incident upon it, +those Rays will begin to be totally reflected by it towards N; and first +the most refrangible Rays will be totally reflected (as was explained in +the preceding Experiment) and by Consequence must first disappear at P, +and afterwards the rest as they are in order totally reflected to N, +they must disappear in the same order at R and T. So then the Rays which +at O suffer the greatest Refraction, may be taken out of the Light MO +whilst the rest of the Rays remain in it, and therefore that Light MO is +compounded of Rays differently refrangible. And because the Planes AB +and CD are parallel, and therefore by equal and contrary Refractions +destroy one anothers Effects, the incident Light FM must be of the same +Kind and Nature with the emergent Light MO, and therefore doth also +consist of Rays differently refrangible. These two Lights FM and MO, +before the most refrangible Rays are separated out of the emergent Light +MO, agree in Colour, and in all other Properties so far as my +Observation reaches, and therefore are deservedly reputed of the same +Nature and Constitution, and by Consequence the one is compounded as +well as the other. But after the most refrangible Rays begin to be +totally reflected, and thereby separated out of the emergent Light MO, +that Light changes its Colour from white to a dilute and faint yellow, a +pretty good orange, a very full red successively, and then totally +vanishes. For after the most refrangible Rays which paint the Paper at +P with a purple Colour, are by a total Reflexion taken out of the beam +of Light MO, the rest of the Colours which appear on the Paper at R and +T being mix'd in the Light MO compound there a faint yellow, and after +the blue and part of the green which appear on the Paper between P and R +are taken away, the rest which appear between R and T (that is the +yellow, orange, red and a little green) being mixed in the beam MO +compound there an orange; and when all the Rays are by Reflexion taken +out of the beam MO, except the least refrangible, which at T appear of a +full red, their Colour is the same in that beam MO as afterwards at T, +the Refraction of the Prism HJK serving only to separate the differently +refrangible Rays, without making any Alteration in their Colours, as +shall be more fully proved hereafter. All which confirms as well the +first Proposition as the second. + +_Scholium._ If this Experiment and the former be conjoined and made one +by applying a fourth Prism VXY [in _Fig._ 22.] to refract the reflected +beam MN towards _tp_, the Conclusion will be clearer. For then the Light +N_p_ which in the fourth Prism is more refracted, will become fuller and +stronger when the Light OP, which in the third Prism HJK is more +refracted, vanishes at P; and afterwards when the less refracted Light +OT vanishes at T, the less refracted Light N_t_ will become increased +whilst the more refracted Light at _p_ receives no farther increase. And +as the trajected beam MO in vanishing is always of such a Colour as +ought to result from the mixture of the Colours which fall upon the +Paper PT, so is the reflected beam MN always of such a Colour as ought +to result from the mixture of the Colours which fall upon the Paper +_pt_. For when the most refrangible Rays are by a total Reflexion taken +out of the beam MO, and leave that beam of an orange Colour, the Excess +of those Rays in the reflected Light, does not only make the violet, +indigo and blue at _p_ more full, but also makes the beam MN change from +the yellowish Colour of the Sun's Light, to a pale white inclining to +blue, and afterward recover its yellowish Colour again, so soon as all +the rest of the transmitted Light MOT is reflected. + +Now seeing that in all this variety of Experiments, whether the Trial be +made in Light reflected, and that either from natural Bodies, as in the +first and second Experiment, or specular, as in the ninth; or in Light +refracted, and that either before the unequally refracted Rays are by +diverging separated from one another, and losing their whiteness which +they have altogether, appear severally of several Colours, as in the +fifth Experiment; or after they are separated from one another, and +appear colour'd as in the sixth, seventh, and eighth Experiments; or in +Light trajected through parallel Superficies, destroying each others +Effects, as in the tenth Experiment; there are always found Rays, which +at equal Incidences on the same Medium suffer unequal Refractions, and +that without any splitting or dilating of single Rays, or contingence in +the inequality of the Refractions, as is proved in the fifth and sixth +Experiments. And seeing the Rays which differ in Refrangibility may be +parted and sorted from one another, and that either by Refraction as in +the third Experiment, or by Reflexion as in the tenth, and then the +several sorts apart at equal Incidences suffer unequal Refractions, and +those sorts are more refracted than others after Separation, which were +more refracted before it, as in the sixth and following Experiments, and +if the Sun's Light be trajected through three or more cross Prisms +successively, those Rays which in the first Prism are refracted more +than others, are in all the following Prisms refracted more than others +in the same Rate and Proportion, as appears by the fifth Experiment; +it's manifest that the Sun's Light is an heterogeneous Mixture of Rays, +some of which are constantly more refrangible than others, as was +proposed. + + +_PROP._ III. THEOR. III. + +_The Sun's Light consists of Rays differing in Reflexibility, and those +Rays are more reflexible than others which are more refrangible._ + +This is manifest by the ninth and tenth Experiments: For in the ninth +Experiment, by turning the Prism about its Axis, until the Rays within +it which in going out into the Air were refracted by its Base, became so +oblique to that Base, as to begin to be totally reflected thereby; those +Rays became first of all totally reflected, which before at equal +Incidences with the rest had suffered the greatest Refraction. And the +same thing happens in the Reflexion made by the common Base of the two +Prisms in the tenth Experiment. + + +_PROP._ IV. PROB. I. + +_To separate from one another the heterogeneous Rays of compound Light._ + +[Illustration: FIG. 23.] + +The heterogeneous Rays are in some measure separated from one another by +the Refraction of the Prism in the third Experiment, and in the fifth +Experiment, by taking away the Penumbra from the rectilinear sides of +the coloured Image, that Separation in those very rectilinear sides or +straight edges of the Image becomes perfect. But in all places between +those rectilinear edges, those innumerable Circles there described, +which are severally illuminated by homogeneal Rays, by interfering with +one another, and being every where commix'd, do render the Light +sufficiently compound. But if these Circles, whilst their Centers keep +their Distances and Positions, could be made less in Diameter, their +interfering one with another, and by Consequence the Mixture of the +heterogeneous Rays would be proportionally diminish'd. In the twenty +third Figure let AG, BH, CJ, DK, EL, FM be the Circles which so many +sorts of Rays flowing from the same disque of the Sun, do in the third +Experiment illuminate; of all which and innumerable other intermediate +ones lying in a continual Series between the two rectilinear and +parallel edges of the Sun's oblong Image PT, that Image is compos'd, as +was explained in the fifth Experiment. And let _ag_, _bh_, _ci_, _dk_, +_el_, _fm_ be so many less Circles lying in a like continual Series +between two parallel right Lines _af_ and _gm_ with the same distances +between their Centers, and illuminated by the same sorts of Rays, that +is the Circle _ag_ with the same sort by which the corresponding Circle +AG was illuminated, and the Circle _bh_ with the same sort by which the +corresponding Circle BH was illuminated, and the rest of the Circles +_ci_, _dk_, _el_, _fm_ respectively, with the same sorts of Rays by +which the several corresponding Circles CJ, DK, EL, FM were illuminated. +In the Figure PT composed of the greater Circles, three of those Circles +AG, BH, CJ, are so expanded into one another, that the three sorts of +Rays by which those Circles are illuminated, together with other +innumerable sorts of intermediate Rays, are mixed at QR in the middle +of the Circle BH. And the like Mixture happens throughout almost the +whole length of the Figure PT. But in the Figure _pt_ composed of the +less Circles, the three less Circles _ag_, _bh_, _ci_, which answer to +those three greater, do not extend into one another; nor are there any +where mingled so much as any two of the three sorts of Rays by which +those Circles are illuminated, and which in the Figure PT are all of +them intermingled at BH. + +Now he that shall thus consider it, will easily understand that the +Mixture is diminished in the same Proportion with the Diameters of the +Circles. If the Diameters of the Circles whilst their Centers remain the +same, be made three times less than before, the Mixture will be also +three times less; if ten times less, the Mixture will be ten times less, +and so of other Proportions. That is, the Mixture of the Rays in the +greater Figure PT will be to their Mixture in the less _pt_, as the +Latitude of the greater Figure is to the Latitude of the less. For the +Latitudes of these Figures are equal to the Diameters of their Circles. +And hence it easily follows, that the Mixture of the Rays in the +refracted Spectrum _pt_ is to the Mixture of the Rays in the direct and +immediate Light of the Sun, as the breadth of that Spectrum is to the +difference between the length and breadth of the same Spectrum. + +So then, if we would diminish the Mixture of the Rays, we are to +diminish the Diameters of the Circles. Now these would be diminished if +the Sun's Diameter to which they answer could be made less than it is, +or (which comes to the same Purpose) if without Doors, at a great +distance from the Prism towards the Sun, some opake Body were placed, +with a round hole in the middle of it, to intercept all the Sun's Light, +excepting so much as coming from the middle of his Body could pass +through that Hole to the Prism. For so the Circles AG, BH, and the rest, +would not any longer answer to the whole Disque of the Sun, but only to +that Part of it which could be seen from the Prism through that Hole, +that it is to the apparent Magnitude of that Hole view'd from the Prism. +But that these Circles may answer more distinctly to that Hole, a Lens +is to be placed by the Prism to cast the Image of the Hole, (that is, +every one of the Circles AG, BH, &c.) distinctly upon the Paper at PT, +after such a manner, as by a Lens placed at a Window, the Species of +Objects abroad are cast distinctly upon a Paper within the Room, and the +rectilinear Sides of the oblong Solar Image in the fifth Experiment +became distinct without any Penumbra. If this be done, it will not be +necessary to place that Hole very far off, no not beyond the Window. And +therefore instead of that Hole, I used the Hole in the Window-shut, as +follows. + +_Exper._ 11. In the Sun's Light let into my darken'd Chamber through a +small round Hole in my Window-shut, at about ten or twelve Feet from the +Window, I placed a Lens, by which the Image of the Hole might be +distinctly cast upon a Sheet of white Paper, placed at the distance of +six, eight, ten, or twelve Feet from the Lens. For, according to the +difference of the Lenses I used various distances, which I think not +worth the while to describe. Then immediately after the Lens I placed a +Prism, by which the trajected Light might be refracted either upwards or +sideways, and thereby the round Image, which the Lens alone did cast +upon the Paper might be drawn out into a long one with Parallel Sides, +as in the third Experiment. This oblong Image I let fall upon another +Paper at about the same distance from the Prism as before, moving the +Paper either towards the Prism or from it, until I found the just +distance where the Rectilinear Sides of the Image became most distinct. +For in this Case, the Circular Images of the Hole, which compose that +Image after the same manner that the Circles _ag_, _bh_, _ci_, &c. do +the Figure _pt_ [in _Fig._ 23.] were terminated most distinctly without +any Penumbra, and therefore extended into one another the least that +they could, and by consequence the Mixture of the heterogeneous Rays was +now the least of all. By this means I used to form an oblong Image (such +as is _pt_) [in _Fig._ 23, and 24.] of Circular Images of the Hole, +(such as are _ag_, _bh_, _ci_, &c.) and by using a greater or less Hole +in the Window-shut, I made the Circular Images _ag_, _bh_, _ci_, &c. of +which it was formed, to become greater or less at pleasure, and thereby +the Mixture of the Rays in the Image _pt_ to be as much, or as little as +I desired. + +[Illustration: FIG. 24.] + +_Illustration._ In the twenty-fourth Figure, F represents the Circular +Hole in the Window-shut, MN the Lens, whereby the Image or Species of +that Hole is cast distinctly upon a Paper at J, ABC the Prism, whereby +the Rays are at their emerging out of the Lens refracted from J towards +another Paper at _pt_, and the round Image at J is turned into an oblong +Image _pt_ falling on that other Paper. This Image _pt_ consists of +Circles placed one after another in a Rectilinear Order, as was +sufficiently explained in the fifth Experiment; and these Circles are +equal to the Circle J, and consequently answer in magnitude to the Hole +F; and therefore by diminishing that Hole they may be at pleasure +diminished, whilst their Centers remain in their Places. By this means I +made the Breadth of the Image _pt_ to be forty times, and sometimes +sixty or seventy times less than its Length. As for instance, if the +Breadth of the Hole F be one tenth of an Inch, and MF the distance of +the Lens from the Hole be 12 Feet; and if _p_B or _p_M the distance of +the Image _pt_ from the Prism or Lens be 10 Feet, and the refracting +Angle of the Prism be 62 Degrees, the Breadth of the Image _pt_ will be +one twelfth of an Inch, and the Length about six Inches, and therefore +the Length to the Breadth as 72 to 1, and by consequence the Light of +this Image 71 times less compound than the Sun's direct Light. And Light +thus far simple and homogeneal, is sufficient for trying all the +Experiments in this Book about simple Light. For the Composition of +heterogeneal Rays is in this Light so little, that it is scarce to be +discovered and perceiv'd by Sense, except perhaps in the indigo and +violet. For these being dark Colours do easily suffer a sensible Allay +by that little scattering Light which uses to be refracted irregularly +by the Inequalities of the Prism. + +Yet instead of the Circular Hole F, 'tis better to substitute an oblong +Hole shaped like a long Parallelogram with its Length parallel to the +Prism ABC. For if this Hole be an Inch or two long, and but a tenth or +twentieth Part of an Inch broad, or narrower; the Light of the Image +_pt_ will be as simple as before, or simpler, and the Image will become +much broader, and therefore more fit to have Experiments try'd in its +Light than before. + +Instead of this Parallelogram Hole may be substituted a triangular one +of equal Sides, whose Base, for instance, is about the tenth Part of an +Inch, and its Height an Inch or more. For by this means, if the Axis of +the Prism be parallel to the Perpendicular of the Triangle, the Image +_pt_ [in _Fig._ 25.] will now be form'd of equicrural Triangles _ag_, +_bh_, _ci_, _dk_, _el_, _fm_, &c. and innumerable other intermediate +ones answering to the triangular Hole in Shape and Bigness, and lying +one after another in a continual Series between two Parallel Lines _af_ +and _gm_. These Triangles are a little intermingled at their Bases, but +not at their Vertices; and therefore the Light on the brighter Side _af_ +of the Image, where the Bases of the Triangles are, is a little +compounded, but on the darker Side _gm_ is altogether uncompounded, and +in all Places between the Sides the Composition is proportional to the +distances of the Places from that obscurer Side _gm_. And having a +Spectrum _pt_ of such a Composition, we may try Experiments either in +its stronger and less simple Light near the Side _af_, or in its weaker +and simpler Light near the other Side _gm_, as it shall seem most +convenient. + +[Illustration: FIG. 25.] + +But in making Experiments of this kind, the Chamber ought to be made as +dark as can be, lest any Foreign Light mingle it self with the Light of +the Spectrum _pt_, and render it compound; especially if we would try +Experiments in the more simple Light next the Side _gm_ of the Spectrum; +which being fainter, will have a less proportion to the Foreign Light; +and so by the mixture of that Light be more troubled, and made more +compound. The Lens also ought to be good, such as may serve for optical +Uses, and the Prism ought to have a large Angle, suppose of 65 or 70 +Degrees, and to be well wrought, being made of Glass free from Bubbles +and Veins, with its Sides not a little convex or concave, as usually +happens, but truly plane, and its Polish elaborate, as in working +Optick-glasses, and not such as is usually wrought with Putty, whereby +the edges of the Sand-holes being worn away, there are left all over the +Glass a numberless Company of very little convex polite Risings like +Waves. The edges also of the Prism and Lens, so far as they may make any +irregular Refraction, must be covered with a black Paper glewed on. And +all the Light of the Sun's Beam let into the Chamber, which is useless +and unprofitable to the Experiment, ought to be intercepted with black +Paper, or other black Obstacles. For otherwise the useless Light being +reflected every way in the Chamber, will mix with the oblong Spectrum, +and help to disturb it. In trying these Things, so much diligence is not +altogether necessary, but it will promote the Success of the +Experiments, and by a very scrupulous Examiner of Things deserves to be +apply'd. It's difficult to get Glass Prisms fit for this Purpose, and +therefore I used sometimes prismatick Vessels made with pieces of broken +Looking-glasses, and filled with Rain Water. And to increase the +Refraction, I sometimes impregnated the Water strongly with _Saccharum +Saturni_. + + +_PROP._ V. THEOR. IV. + +_Homogeneal Light is refracted regularly without any Dilatation +splitting or shattering of the Rays, and the confused Vision of Objects +seen through refracting Bodies by heterogeneal Light arises from the +different Refrangibility of several sorts of Rays._ + +The first Part of this Proposition has been already sufficiently proved +in the fifth Experiment, and will farther appear by the Experiments +which follow. + +_Exper._ 12. In the middle of a black Paper I made a round Hole about a +fifth or sixth Part of an Inch in diameter. Upon this Paper I caused the +Spectrum of homogeneal Light described in the former Proposition, so to +fall, that some part of the Light might pass through the Hole of the +Paper. This transmitted part of the Light I refracted with a Prism +placed behind the Paper, and letting this refracted Light fall +perpendicularly upon a white Paper two or three Feet distant from the +Prism, I found that the Spectrum formed on the Paper by this Light was +not oblong, as when 'tis made (in the third Experiment) by refracting +the Sun's compound Light, but was (so far as I could judge by my Eye) +perfectly circular, the Length being no greater than the Breadth. Which +shews, that this Light is refracted regularly without any Dilatation of +the Rays. + +_Exper._ 13. In the homogeneal Light I placed a Paper Circle of a +quarter of an Inch in diameter, and in the Sun's unrefracted +heterogeneal white Light I placed another Paper Circle of the same +Bigness. And going from the Papers to the distance of some Feet, I +viewed both Circles through a Prism. The Circle illuminated by the Sun's +heterogeneal Light appeared very oblong, as in the fourth Experiment, +the Length being many times greater than the Breadth; but the other +Circle, illuminated with homogeneal Light, appeared circular and +distinctly defined, as when 'tis view'd with the naked Eye. Which proves +the whole Proposition. + +_Exper._ 14. In the homogeneal Light I placed Flies, and such-like +minute Objects, and viewing them through a Prism, I saw their Parts as +distinctly defined, as if I had viewed them with the naked Eye. The same +Objects placed in the Sun's unrefracted heterogeneal Light, which was +white, I viewed also through a Prism, and saw them most confusedly +defined, so that I could not distinguish their smaller Parts from one +another. I placed also the Letters of a small print, one while in the +homogeneal Light, and then in the heterogeneal, and viewing them through +a Prism, they appeared in the latter Case so confused and indistinct, +that I could not read them; but in the former they appeared so distinct, +that I could read readily, and thought I saw them as distinct, as when I +view'd them with my naked Eye. In both Cases I view'd the same Objects, +through the same Prism at the same distance from me, and in the same +Situation. There was no difference, but in the Light by which the +Objects were illuminated, and which in one Case was simple, and in the +other compound; and therefore, the distinct Vision in the former Case, +and confused in the latter, could arise from nothing else than from that +difference of the Lights. Which proves the whole Proposition. + +And in these three Experiments it is farther very remarkable, that the +Colour of homogeneal Light was never changed by the Refraction. + + +_PROP._ VI. THEOR. V. + +_The Sine of Incidence of every Ray considered apart, is to its Sine of +Refraction in a given Ratio._ + +That every Ray consider'd apart, is constant to it self in some degree +of Refrangibility, is sufficiently manifest out of what has been said. +Those Rays, which in the first Refraction, are at equal Incidences most +refracted, are also in the following Refractions at equal Incidences +most refracted; and so of the least refrangible, and the rest which have +any mean Degree of Refrangibility, as is manifest by the fifth, sixth, +seventh, eighth, and ninth Experiments. And those which the first Time +at like Incidences are equally refracted, are again at like Incidences +equally and uniformly refracted, and that whether they be refracted +before they be separated from one another, as in the fifth Experiment, +or whether they be refracted apart, as in the twelfth, thirteenth and +fourteenth Experiments. The Refraction therefore of every Ray apart is +regular, and what Rule that Refraction observes we are now to shew.[E] + +The late Writers in Opticks teach, that the Sines of Incidence are in a +given Proportion to the Sines of Refraction, as was explained in the +fifth Axiom, and some by Instruments fitted for measuring of +Refractions, or otherwise experimentally examining this Proportion, do +acquaint us that they have found it accurate. But whilst they, not +understanding the different Refrangibility of several Rays, conceived +them all to be refracted according to one and the same Proportion, 'tis +to be presumed that they adapted their Measures only to the middle of +the refracted Light; so that from their Measures we may conclude only +that the Rays which have a mean Degree of Refrangibility, that is, those +which when separated from the rest appear green, are refracted according +to a given Proportion of their Sines. And therefore we are now to shew, +that the like given Proportions obtain in all the rest. That it should +be so is very reasonable, Nature being ever conformable to her self; but +an experimental Proof is desired. And such a Proof will be had, if we +can shew that the Sines of Refraction of Rays differently refrangible +are one to another in a given Proportion when their Sines of Incidence +are equal. For, if the Sines of Refraction of all the Rays are in given +Proportions to the Sine of Refractions of a Ray which has a mean Degree +of Refrangibility, and this Sine is in a given Proportion to the equal +Sines of Incidence, those other Sines of Refraction will also be in +given Proportions to the equal Sines of Incidence. Now, when the Sines +of Incidence are equal, it will appear by the following Experiment, that +the Sines of Refraction are in a given Proportion to one another. + +[Illustration: FIG. 26.] + +_Exper._ 15. The Sun shining into a dark Chamber through a little round +Hole in the Window-shut, let S [in _Fig._ 26.] represent his round white +Image painted on the opposite Wall by his direct Light, PT his oblong +coloured Image made by refracting that Light with a Prism placed at the +Window; and _pt_, or _2p 2t_, _3p 3t_, his oblong colour'd Image made by +refracting again the same Light sideways with a second Prism placed +immediately after the first in a cross Position to it, as was explained +in the fifth Experiment; that is to say, _pt_ when the Refraction of the +second Prism is small, _2p 2t_ when its Refraction is greater, and _3p +3t_ when it is greatest. For such will be the diversity of the +Refractions, if the refracting Angle of the second Prism be of various +Magnitudes; suppose of fifteen or twenty Degrees to make the Image _pt_, +of thirty or forty to make the Image _2p 2t_, and of sixty to make the +Image _3p 3t_. But for want of solid Glass Prisms with Angles of +convenient Bignesses, there may be Vessels made of polished Plates of +Glass cemented together in the form of Prisms and filled with Water. +These things being thus ordered, I observed that all the solar Images or +coloured Spectrums PT, _pt_, _2p 2t_, _3p 3t_ did very nearly converge +to the place S on which the direct Light of the Sun fell and painted his +white round Image when the Prisms were taken away. The Axis of the +Spectrum PT, that is the Line drawn through the middle of it parallel to +its rectilinear Sides, did when produced pass exactly through the middle +of that white round Image S. And when the Refraction of the second Prism +was equal to the Refraction of the first, the refracting Angles of them +both being about 60 Degrees, the Axis of the Spectrum _3p 3t_ made by +that Refraction, did when produced pass also through the middle of the +same white round Image S. But when the Refraction of the second Prism +was less than that of the first, the produced Axes of the Spectrums _tp_ +or _2t 2p_ made by that Refraction did cut the produced Axis of the +Spectrum TP in the points _m_ and _n_, a little beyond the Center of +that white round Image S. Whence the proportion of the Line 3_t_T to the +Line 3_p_P was a little greater than the Proportion of 2_t_T or 2_p_P, +and this Proportion a little greater than that of _t_T to _p_P. Now when +the Light of the Spectrum PT falls perpendicularly upon the Wall, those +Lines 3_t_T, 3_p_P, and 2_t_T, and 2_p_P, and _t_T, _p_P, are the +Tangents of the Refractions, and therefore by this Experiment the +Proportions of the Tangents of the Refractions are obtained, from whence +the Proportions of the Sines being derived, they come out equal, so far +as by viewing the Spectrums, and using some mathematical Reasoning I +could estimate. For I did not make an accurate Computation. So then the +Proposition holds true in every Ray apart, so far as appears by +Experiment. And that it is accurately true, may be demonstrated upon +this Supposition. _That Bodies refract Light by acting upon its Rays in +Lines perpendicular to their Surfaces._ But in order to this +Demonstration, I must distinguish the Motion of every Ray into two +Motions, the one perpendicular to the refracting Surface, the other +parallel to it, and concerning the perpendicular Motion lay down the +following Proposition. + +If any Motion or moving thing whatsoever be incident with any Velocity +on any broad and thin space terminated on both sides by two parallel +Planes, and in its Passage through that space be urged perpendicularly +towards the farther Plane by any force which at given distances from the +Plane is of given Quantities; the perpendicular velocity of that Motion +or Thing, at its emerging out of that space, shall be always equal to +the square Root of the sum of the square of the perpendicular velocity +of that Motion or Thing at its Incidence on that space; and of the +square of the perpendicular velocity which that Motion or Thing would +have at its Emergence, if at its Incidence its perpendicular velocity +was infinitely little. + +And the same Proposition holds true of any Motion or Thing +perpendicularly retarded in its passage through that space, if instead +of the sum of the two Squares you take their difference. The +Demonstration Mathematicians will easily find out, and therefore I shall +not trouble the Reader with it. + +Suppose now that a Ray coming most obliquely in the Line MC [in _Fig._ +1.] be refracted at C by the Plane RS into the Line CN, and if it be +required to find the Line CE, into which any other Ray AC shall be +refracted; let MC, AD, be the Sines of Incidence of the two Rays, and +NG, EF, their Sines of Refraction, and let the equal Motions of the +incident Rays be represented by the equal Lines MC and AC, and the +Motion MC being considered as parallel to the refracting Plane, let the +other Motion AC be distinguished into two Motions AD and DC, one of +which AD is parallel, and the other DC perpendicular to the refracting +Surface. In like manner, let the Motions of the emerging Rays be +distinguish'd into two, whereof the perpendicular ones are MC/NG × CG +and AD/EF × CF. And if the force of the refracting Plane begins to act +upon the Rays either in that Plane or at a certain distance from it on +the one side, and ends at a certain distance from it on the other side, +and in all places between those two limits acts upon the Rays in Lines +perpendicular to that refracting Plane, and the Actions upon the Rays at +equal distances from the refracting Plane be equal, and at unequal ones +either equal or unequal according to any rate whatever; that Motion of +the Ray which is parallel to the refracting Plane, will suffer no +Alteration by that Force; and that Motion which is perpendicular to it +will be altered according to the rule of the foregoing Proposition. If +therefore for the perpendicular velocity of the emerging Ray CN you +write MC/NG × CG as above, then the perpendicular velocity of any other +emerging Ray CE which was AD/EF × CF, will be equal to the square Root +of CD_q_ + (_MCq/NGq_ × CG_q_). And by squaring these Equals, and adding +to them the Equals AD_q_ and MC_q_ - CD_q_, and dividing the Sums by the +Equals CF_q_ + EF_q_ and CG_q_ + NG_q_, you will have _MCq/NGq_ equal to +_ADq/EFq_. Whence AD, the Sine of Incidence, is to EF the Sine of +Refraction, as MC to NG, that is, in a given _ratio_. And this +Demonstration being general, without determining what Light is, or by +what kind of Force it is refracted, or assuming any thing farther than +that the refracting Body acts upon the Rays in Lines perpendicular to +its Surface; I take it to be a very convincing Argument of the full +truth of this Proposition. + +So then, if the _ratio_ of the Sines of Incidence and Refraction of any +sort of Rays be found in any one case, 'tis given in all cases; and this +may be readily found by the Method in the following Proposition. + + +_PROP._ VII. THEOR. VI. + +_The Perfection of Telescopes is impeded by the different Refrangibility +of the Rays of Light._ + +The Imperfection of Telescopes is vulgarly attributed to the spherical +Figures of the Glasses, and therefore Mathematicians have propounded to +figure them by the conical Sections. To shew that they are mistaken, I +have inserted this Proposition; the truth of which will appear by the +measure of the Refractions of the several sorts of Rays; and these +measures I thus determine. + +In the third Experiment of this first Part, where the refracting Angle +of the Prism was 62-1/2 Degrees, the half of that Angle 31 deg. 15 min. +is the Angle of Incidence of the Rays at their going out of the Glass +into the Air[F]; and the Sine of this Angle is 5188, the Radius being +10000. When the Axis of this Prism was parallel to the Horizon, and the +Refraction of the Rays at their Incidence on this Prism equal to that at +their Emergence out of it, I observed with a Quadrant the Angle which +the mean refrangible Rays, (that is those which went to the middle of +the Sun's coloured Image) made with the Horizon, and by this Angle and +the Sun's altitude observed at the same time, I found the Angle which +the emergent Rays contained with the incident to be 44 deg. and 40 min. +and the half of this Angle added to the Angle of Incidence 31 deg. 15 +min. makes the Angle of Refraction, which is therefore 53 deg. 35 min. +and its Sine 8047. These are the Sines of Incidence and Refraction of +the mean refrangible Rays, and their Proportion in round Numbers is 20 +to 31. This Glass was of a Colour inclining to green. The last of the +Prisms mentioned in the third Experiment was of clear white Glass. Its +refracting Angle 63-1/2 Degrees. The Angle which the emergent Rays +contained, with the incident 45 deg. 50 min. The Sine of half the first +Angle 5262. The Sine of half the Sum of the Angles 8157. And their +Proportion in round Numbers 20 to 31, as before. + +From the Length of the Image, which was about 9-3/4 or 10 Inches, +subduct its Breadth, which was 2-1/8 Inches, and the Remainder 7-3/4 +Inches would be the Length of the Image were the Sun but a Point, and +therefore subtends the Angle which the most and least refrangible Rays, +when incident on the Prism in the same Lines, do contain with one +another after their Emergence. Whence this Angle is 2 deg. 0´. 7´´. For +the distance between the Image and the Prism where this Angle is made, +was 18-1/2 Feet, and at that distance the Chord 7-3/4 Inches subtends an +Angle of 2 deg. 0´. 7´´. Now half this Angle is the Angle which these +emergent Rays contain with the emergent mean refrangible Rays, and a +quarter thereof, that is 30´. 2´´. may be accounted the Angle which they +would contain with the same emergent mean refrangible Rays, were they +co-incident to them within the Glass, and suffered no other Refraction +than that at their Emergence. For, if two equal Refractions, the one at +the Incidence of the Rays on the Prism, the other at their Emergence, +make half the Angle 2 deg. 0´. 7´´. then one of those Refractions will +make about a quarter of that Angle, and this quarter added to, and +subducted from the Angle of Refraction of the mean refrangible Rays, +which was 53 deg. 35´, gives the Angles of Refraction of the most and +least refrangible Rays 54 deg. 5´ 2´´, and 53 deg. 4´ 58´´, whose Sines +are 8099 and 7995, the common Angle of Incidence being 31 deg. 15´, and +its Sine 5188; and these Sines in the least round Numbers are in +proportion to one another, as 78 and 77 to 50. + +Now, if you subduct the common Sine of Incidence 50 from the Sines of +Refraction 77 and 78, the Remainders 27 and 28 shew, that in small +Refractions the Refraction of the least refrangible Rays is to the +Refraction of the most refrangible ones, as 27 to 28 very nearly, and +that the difference of the Refractions of the least refrangible and most +refrangible Rays is about the 27-1/2th Part of the whole Refraction of +the mean refrangible Rays. + +Whence they that are skilled in Opticks will easily understand,[G] that +the Breadth of the least circular Space, into which Object-glasses of +Telescopes can collect all sorts of Parallel Rays, is about the 27-1/2th +Part of half the Aperture of the Glass, or 55th Part of the whole +Aperture; and that the Focus of the most refrangible Rays is nearer to +the Object-glass than the Focus of the least refrangible ones, by about +the 27-1/2th Part of the distance between the Object-glass and the Focus +of the mean refrangible ones. + +And if Rays of all sorts, flowing from any one lucid Point in the Axis +of any convex Lens, be made by the Refraction of the Lens to converge to +Points not too remote from the Lens, the Focus of the most refrangible +Rays shall be nearer to the Lens than the Focus of the least refrangible +ones, by a distance which is to the 27-1/2th Part of the distance of the +Focus of the mean refrangible Rays from the Lens, as the distance +between that Focus and the lucid Point, from whence the Rays flow, is to +the distance between that lucid Point and the Lens very nearly. + +Now to examine whether the Difference between the Refractions, which the +most refrangible and the least refrangible Rays flowing from the same +Point suffer in the Object-glasses of Telescopes and such-like Glasses, +be so great as is here described, I contrived the following Experiment. + +_Exper._ 16. The Lens which I used in the second and eighth Experiments, +being placed six Feet and an Inch distant from any Object, collected the +Species of that Object by the mean refrangible Rays at the distance of +six Feet and an Inch from the Lens on the other side. And therefore by +the foregoing Rule, it ought to collect the Species of that Object by +the least refrangible Rays at the distance of six Feet and 3-2/3 Inches +from the Lens, and by the most refrangible ones at the distance of five +Feet and 10-1/3 Inches from it: So that between the two Places, where +these least and most refrangible Rays collect the Species, there may be +the distance of about 5-1/3 Inches. For by that Rule, as six Feet and an +Inch (the distance of the Lens from the lucid Object) is to twelve Feet +and two Inches (the distance of the lucid Object from the Focus of the +mean refrangible Rays) that is, as One is to Two; so is the 27-1/2th +Part of six Feet and an Inch (the distance between the Lens and the same +Focus) to the distance between the Focus of the most refrangible Rays +and the Focus of the least refrangible ones, which is therefore 5-17/55 +Inches, that is very nearly 5-1/3 Inches. Now to know whether this +Measure was true, I repeated the second and eighth Experiment with +coloured Light, which was less compounded than that I there made use of: +For I now separated the heterogeneous Rays from one another by the +Method I described in the eleventh Experiment, so as to make a coloured +Spectrum about twelve or fifteen Times longer than broad. This Spectrum +I cast on a printed Book, and placing the above-mentioned Lens at the +distance of six Feet and an Inch from this Spectrum to collect the +Species of the illuminated Letters at the same distance on the other +side, I found that the Species of the Letters illuminated with blue were +nearer to the Lens than those illuminated with deep red by about three +Inches, or three and a quarter; but the Species of the Letters +illuminated with indigo and violet appeared so confused and indistinct, +that I could not read them: Whereupon viewing the Prism, I found it was +full of Veins running from one end of the Glass to the other; so that +the Refraction could not be regular. I took another Prism therefore +which was free from Veins, and instead of the Letters I used two or +three Parallel black Lines a little broader than the Strokes of the +Letters, and casting the Colours upon these Lines in such manner, that +the Lines ran along the Colours from one end of the Spectrum to the +other, I found that the Focus where the indigo, or confine of this +Colour and violet cast the Species of the black Lines most distinctly, +to be about four Inches, or 4-1/4 nearer to the Lens than the Focus, +where the deepest red cast the Species of the same black Lines most +distinctly. The violet was so faint and dark, that I could not discern +the Species of the Lines distinctly by that Colour; and therefore +considering that the Prism was made of a dark coloured Glass inclining +to green, I took another Prism of clear white Glass; but the Spectrum of +Colours which this Prism made had long white Streams of faint Light +shooting out from both ends of the Colours, which made me conclude that +something was amiss; and viewing the Prism, I found two or three little +Bubbles in the Glass, which refracted the Light irregularly. Wherefore I +covered that Part of the Glass with black Paper, and letting the Light +pass through another Part of it which was free from such Bubbles, the +Spectrum of Colours became free from those irregular Streams of Light, +and was now such as I desired. But still I found the violet so dark and +faint, that I could scarce see the Species of the Lines by the violet, +and not at all by the deepest Part of it, which was next the end of the +Spectrum. I suspected therefore, that this faint and dark Colour might +be allayed by that scattering Light which was refracted, and reflected +irregularly, partly by some very small Bubbles in the Glasses, and +partly by the Inequalities of their Polish; which Light, tho' it was but +little, yet it being of a white Colour, might suffice to affect the +Sense so strongly as to disturb the Phænomena of that weak and dark +Colour the violet, and therefore I tried, as in the 12th, 13th, and 14th +Experiments, whether the Light of this Colour did not consist of a +sensible Mixture of heterogeneous Rays, but found it did not. Nor did +the Refractions cause any other sensible Colour than violet to emerge +out of this Light, as they would have done out of white Light, and by +consequence out of this violet Light had it been sensibly compounded +with white Light. And therefore I concluded, that the reason why I could +not see the Species of the Lines distinctly by this Colour, was only +the Darkness of this Colour, and Thinness of its Light, and its distance +from the Axis of the Lens; I divided therefore those Parallel black +Lines into equal Parts, by which I might readily know the distances of +the Colours in the Spectrum from one another, and noted the distances of +the Lens from the Foci of such Colours, as cast the Species of the Lines +distinctly, and then considered whether the difference of those +distances bear such proportion to 5-1/3 Inches, the greatest Difference +of the distances, which the Foci of the deepest red and violet ought to +have from the Lens, as the distance of the observed Colours from one +another in the Spectrum bear to the greatest distance of the deepest red +and violet measured in the Rectilinear Sides of the Spectrum, that is, +to the Length of those Sides, or Excess of the Length of the Spectrum +above its Breadth. And my Observations were as follows. + +When I observed and compared the deepest sensible red, and the Colour in +the Confine of green and blue, which at the Rectilinear Sides of the +Spectrum was distant from it half the Length of those Sides, the Focus +where the Confine of green and blue cast the Species of the Lines +distinctly on the Paper, was nearer to the Lens than the Focus, where +the red cast those Lines distinctly on it by about 2-1/2 or 2-3/4 +Inches. For sometimes the Measures were a little greater, sometimes a +little less, but seldom varied from one another above 1/3 of an Inch. +For it was very difficult to define the Places of the Foci, without some +little Errors. Now, if the Colours distant half the Length of the +Image, (measured at its Rectilinear Sides) give 2-1/2 or 2-3/4 +Difference of the distances of their Foci from the Lens, then the +Colours distant the whole Length ought to give 5 or 5-1/2 Inches +difference of those distances. + +But here it's to be noted, that I could not see the red to the full end +of the Spectrum, but only to the Center of the Semicircle which bounded +that end, or a little farther; and therefore I compared this red not +with that Colour which was exactly in the middle of the Spectrum, or +Confine of green and blue, but with that which verged a little more to +the blue than to the green: And as I reckoned the whole Length of the +Colours not to be the whole Length of the Spectrum, but the Length of +its Rectilinear Sides, so compleating the semicircular Ends into +Circles, when either of the observed Colours fell within those Circles, +I measured the distance of that Colour from the semicircular End of the +Spectrum, and subducting half this distance from the measured distance +of the two Colours, I took the Remainder for their corrected distance; +and in these Observations set down this corrected distance for the +difference of the distances of their Foci from the Lens. For, as the +Length of the Rectilinear Sides of the Spectrum would be the whole +Length of all the Colours, were the Circles of which (as we shewed) that +Spectrum consists contracted and reduced to Physical Points, so in that +Case this corrected distance would be the real distance of the two +observed Colours. + +When therefore I farther observed the deepest sensible red, and that +blue whose corrected distance from it was 7/12 Parts of the Length of +the Rectilinear Sides of the Spectrum, the difference of the distances +of their Foci from the Lens was about 3-1/4 Inches, and as 7 to 12, so +is 3-1/4 to 5-4/7. + +When I observed the deepest sensible red, and that indigo whose +corrected distance was 8/12 or 2/3 of the Length of the Rectilinear +Sides of the Spectrum, the difference of the distances of their Foci +from the Lens, was about 3-2/3 Inches, and as 2 to 3, so is 3-2/3 to +5-1/2. + +When I observed the deepest sensible red, and that deep indigo whose +corrected distance from one another was 9/12 or 3/4 of the Length of the +Rectilinear Sides of the Spectrum, the difference of the distances of +their Foci from the Lens was about 4 Inches; and as 3 to 4, so is 4 to +5-1/3. + +When I observed the deepest sensible red, and that Part of the violet +next the indigo, whose corrected distance from the red was 10/12 or 5/6 +of the Length of the Rectilinear Sides of the Spectrum, the difference +of the distances of their Foci from the Lens was about 4-1/2 Inches, and +as 5 to 6, so is 4-1/2 to 5-2/5. For sometimes, when the Lens was +advantageously placed, so that its Axis respected the blue, and all +Things else were well ordered, and the Sun shone clear, and I held my +Eye very near to the Paper on which the Lens cast the Species of the +Lines, I could see pretty distinctly the Species of those Lines by that +Part of the violet which was next the indigo; and sometimes I could see +them by above half the violet, For in making these Experiments I had +observed, that the Species of those Colours only appear distinct, which +were in or near the Axis of the Lens: So that if the blue or indigo were +in the Axis, I could see their Species distinctly; and then the red +appeared much less distinct than before. Wherefore I contrived to make +the Spectrum of Colours shorter than before, so that both its Ends might +be nearer to the Axis of the Lens. And now its Length was about 2-1/2 +Inches, and Breadth about 1/5 or 1/6 of an Inch. Also instead of the +black Lines on which the Spectrum was cast, I made one black Line +broader than those, that I might see its Species more easily; and this +Line I divided by short cross Lines into equal Parts, for measuring the +distances of the observed Colours. And now I could sometimes see the +Species of this Line with its Divisions almost as far as the Center of +the semicircular violet End of the Spectrum, and made these farther +Observations. + +When I observed the deepest sensible red, and that Part of the violet, +whose corrected distance from it was about 8/9 Parts of the Rectilinear +Sides of the Spectrum, the Difference of the distances of the Foci of +those Colours from the Lens, was one time 4-2/3, another time 4-3/4, +another time 4-7/8 Inches; and as 8 to 9, so are 4-2/3, 4-3/4, 4-7/8, to +5-1/4, 5-11/32, 5-31/64 respectively. + +When I observed the deepest sensible red, and deepest sensible violet, +(the corrected distance of which Colours, when all Things were ordered +to the best Advantage, and the Sun shone very clear, was about 11/12 or +15/16 Parts of the Length of the Rectilinear Sides of the coloured +Spectrum) I found the Difference of the distances of their Foci from the +Lens sometimes 4-3/4 sometimes 5-1/4, and for the most part 5 Inches or +thereabouts; and as 11 to 12, or 15 to 16, so is five Inches to 5-2/2 or +5-1/3 Inches. + +And by this Progression of Experiments I satisfied my self, that had the +Light at the very Ends of the Spectrum been strong enough to make the +Species of the black Lines appear plainly on the Paper, the Focus of the +deepest violet would have been found nearer to the Lens, than the Focus +of the deepest red, by about 5-1/3 Inches at least. And this is a +farther Evidence, that the Sines of Incidence and Refraction of the +several sorts of Rays, hold the same Proportion to one another in the +smallest Refractions which they do in the greatest. + +My Progress in making this nice and troublesome Experiment I have set +down more at large, that they that shall try it after me may be aware of +the Circumspection requisite to make it succeed well. And if they cannot +make it succeed so well as I did, they may notwithstanding collect by +the Proportion of the distance of the Colours of the Spectrum, to the +Difference of the distances of their Foci from the Lens, what would be +the Success in the more distant Colours by a better trial. And yet, if +they use a broader Lens than I did, and fix it to a long strait Staff, +by means of which it may be readily and truly directed to the Colour +whose Focus is desired, I question not but the Experiment will succeed +better with them than it did with me. For I directed the Axis as nearly +as I could to the middle of the Colours, and then the faint Ends of the +Spectrum being remote from the Axis, cast their Species less distinctly +on the Paper than they would have done, had the Axis been successively +directed to them. + +Now by what has been said, it's certain that the Rays which differ in +Refrangibility do not converge to the same Focus; but if they flow from +a lucid Point, as far from the Lens on one side as their Foci are on the +other, the Focus of the most refrangible Rays shall be nearer to the +Lens than that of the least refrangible, by above the fourteenth Part of +the whole distance; and if they flow from a lucid Point, so very remote +from the Lens, that before their Incidence they may be accounted +parallel, the Focus of the most refrangible Rays shall be nearer to the +Lens than the Focus of the least refrangible, by about the 27th or 28th +Part of their whole distance from it. And the Diameter of the Circle in +the middle Space between those two Foci which they illuminate, when they +fall there on any Plane, perpendicular to the Axis (which Circle is the +least into which they can all be gathered) is about the 55th Part of the +Diameter of the Aperture of the Glass. So that 'tis a wonder, that +Telescopes represent Objects so distinct as they do. But were all the +Rays of Light equally refrangible, the Error arising only from the +Sphericalness of the Figures of Glasses would be many hundred times +less. For, if the Object-glass of a Telescope be Plano-convex, and the +Plane side be turned towards the Object, and the Diameter of the +Sphere, whereof this Glass is a Segment, be called D, and the +Semi-diameter of the Aperture of the Glass be called S, and the Sine of +Incidence out of Glass into Air, be to the Sine of Refraction as I to R; +the Rays which come parallel to the Axis of the Glass, shall in the +Place where the Image of the Object is most distinctly made, be +scattered all over a little Circle, whose Diameter is _(Rq/Iq) × (S +cub./D quad.)_ very nearly,[H] as I gather by computing the Errors of +the Rays by the Method of infinite Series, and rejecting the Terms, +whose Quantities are inconsiderable. As for instance, if the Sine of +Incidence I, be to the Sine of Refraction R, as 20 to 31, and if D the +Diameter of the Sphere, to which the Convex-side of the Glass is ground, +be 100 Feet or 1200 Inches, and S the Semi-diameter of the Aperture be +two Inches, the Diameter of the little Circle, (that is (_Rq × S +cub.)/(Iq × D quad._)) will be (31 × 31 × 8)/(20 × 20 × 1200 × 1200) (or +961/72000000) Parts of an Inch. But the Diameter of the little Circle, +through which these Rays are scattered by unequal Refrangibility, will +be about the 55th Part of the Aperture of the Object-glass, which here +is four Inches. And therefore, the Error arising from the Spherical +Figure of the Glass, is to the Error arising from the different +Refrangibility of the Rays, as 961/72000000 to 4/55, that is as 1 to +5449; and therefore being in comparison so very little, deserves not to +be considered. + +[Illustration: FIG. 27.] + +But you will say, if the Errors caused by the different Refrangibility +be so very great, how comes it to pass, that Objects appear through +Telescopes so distinct as they do? I answer, 'tis because the erring +Rays are not scattered uniformly over all that Circular Space, but +collected infinitely more densely in the Center than in any other Part +of the Circle, and in the Way from the Center to the Circumference, grow +continually rarer and rarer, so as at the Circumference to become +infinitely rare; and by reason of their Rarity are not strong enough to +be visible, unless in the Center and very near it. Let ADE [in _Fig._ +27.] represent one of those Circles described with the Center C, and +Semi-diameter AC, and let BFG be a smaller Circle concentrick to the +former, cutting with its Circumference the Diameter AC in B, and bisect +AC in N; and by my reckoning, the Density of the Light in any Place B, +will be to its Density in N, as AB to BC; and the whole Light within the +lesser Circle BFG, will be to the whole Light within the greater AED, as +the Excess of the Square of AC above the Square of AB, is to the Square +of AC. As if BC be the fifth Part of AC, the Light will be four times +denser in B than in N, and the whole Light within the less Circle, will +be to the whole Light within the greater, as nine to twenty-five. Whence +it's evident, that the Light within the less Circle, must strike the +Sense much more strongly, than that faint and dilated Light round about +between it and the Circumference of the greater. + +But it's farther to be noted, that the most luminous of the Prismatick +Colours are the yellow and orange. These affect the Senses more strongly +than all the rest together, and next to these in strength are the red +and green. The blue compared with these is a faint and dark Colour, and +the indigo and violet are much darker and fainter, so that these +compared with the stronger Colours are little to be regarded. The Images +of Objects are therefore to be placed, not in the Focus of the mean +refrangible Rays, which are in the Confine of green and blue, but in the +Focus of those Rays which are in the middle of the orange and yellow; +there where the Colour is most luminous and fulgent, that is in the +brightest yellow, that yellow which inclines more to orange than to +green. And by the Refraction of these Rays (whose Sines of Incidence and +Refraction in Glass are as 17 and 11) the Refraction of Glass and +Crystal for Optical Uses is to be measured. Let us therefore place the +Image of the Object in the Focus of these Rays, and all the yellow and +orange will fall within a Circle, whose Diameter is about the 250th +Part of the Diameter of the Aperture of the Glass. And if you add the +brighter half of the red, (that half which is next the orange) and the +brighter half of the green, (that half which is next the yellow) about +three fifth Parts of the Light of these two Colours will fall within the +same Circle, and two fifth Parts will fall without it round about; and +that which falls without will be spread through almost as much more +space as that which falls within, and so in the gross be almost three +times rarer. Of the other half of the red and green, (that is of the +deep dark red and willow green) about one quarter will fall within this +Circle, and three quarters without, and that which falls without will be +spread through about four or five times more space than that which falls +within; and so in the gross be rarer, and if compared with the whole +Light within it, will be about 25 times rarer than all that taken in the +gross; or rather more than 30 or 40 times rarer, because the deep red in +the end of the Spectrum of Colours made by a Prism is very thin and +rare, and the willow green is something rarer than the orange and +yellow. The Light of these Colours therefore being so very much rarer +than that within the Circle, will scarce affect the Sense, especially +since the deep red and willow green of this Light, are much darker +Colours than the rest. And for the same reason the blue and violet being +much darker Colours than these, and much more rarified, may be +neglected. For the dense and bright Light of the Circle, will obscure +the rare and weak Light of these dark Colours round about it, and +render them almost insensible. The sensible Image of a lucid Point is +therefore scarce broader than a Circle, whose Diameter is the 250th Part +of the Diameter of the Aperture of the Object-glass of a good Telescope, +or not much broader, if you except a faint and dark misty Light round +about it, which a Spectator will scarce regard. And therefore in a +Telescope, whose Aperture is four Inches, and Length an hundred Feet, it +exceeds not 2´´ 45´´´, or 3´´. And in a Telescope whose Aperture is two +Inches, and Length 20 or 30 Feet, it may be 5´´ or 6´´, and scarce +above. And this answers well to Experience: For some Astronomers have +found the Diameters of the fix'd Stars, in Telescopes of between 20 and +60 Feet in length, to be about 5´´ or 6´´, or at most 8´´ or 10´´ in +diameter. But if the Eye-Glass be tincted faintly with the Smoak of a +Lamp or Torch, to obscure the Light of the Star, the fainter Light in +the Circumference of the Star ceases to be visible, and the Star (if the +Glass be sufficiently soiled with Smoak) appears something more like a +mathematical Point. And for the same Reason, the enormous Part of the +Light in the Circumference of every lucid Point ought to be less +discernible in shorter Telescopes than in longer, because the shorter +transmit less Light to the Eye. + +Now, that the fix'd Stars, by reason of their immense Distance, appear +like Points, unless so far as their Light is dilated by Refraction, may +appear from hence; that when the Moon passes over them and eclipses +them, their Light vanishes, not gradually like that of the Planets, but +all at once; and in the end of the Eclipse it returns into Sight all at +once, or certainly in less time than the second of a Minute; the +Refraction of the Moon's Atmosphere a little protracting the time in +which the Light of the Star first vanishes, and afterwards returns into +Sight. + +Now, if we suppose the sensible Image of a lucid Point, to be even 250 +times narrower than the Aperture of the Glass; yet this Image would be +still much greater than if it were only from the spherical Figure of the +Glass. For were it not for the different Refrangibility of the Rays, its +breadth in an 100 Foot Telescope whose aperture is 4 Inches, would be +but 961/72000000 parts of an Inch, as is manifest by the foregoing +Computation. And therefore in this case the greatest Errors arising from +the spherical Figure of the Glass, would be to the greatest sensible +Errors arising from the different Refrangibility of the Rays as +961/72000000 to 4/250 at most, that is only as 1 to 1200. And this +sufficiently shews that it is not the spherical Figures of Glasses, but +the different Refrangibility of the Rays which hinders the perfection of +Telescopes. + +There is another Argument by which it may appear that the different +Refrangibility of Rays, is the true cause of the imperfection of +Telescopes. For the Errors of the Rays arising from the spherical +Figures of Object-glasses, are as the Cubes of the Apertures of the +Object Glasses; and thence to make Telescopes of various Lengths magnify +with equal distinctness, the Apertures of the Object-glasses, and the +Charges or magnifying Powers ought to be as the Cubes of the square +Roots of their lengths; which doth not answer to Experience. But the +Errors of the Rays arising from the different Refrangibility, are as the +Apertures of the Object-glasses; and thence to make Telescopes of +various lengths, magnify with equal distinctness, their Apertures and +Charges ought to be as the square Roots of their lengths; and this +answers to Experience, as is well known. For Instance, a Telescope of 64 +Feet in length, with an Aperture of 2-2/3 Inches, magnifies about 120 +times, with as much distinctness as one of a Foot in length, with 1/3 of +an Inch aperture, magnifies 15 times. + +[Illustration: FIG. 28.] + +Now were it not for this different Refrangibility of Rays, Telescopes +might be brought to a greater perfection than we have yet describ'd, by +composing the Object-glass of two Glasses with Water between them. Let +ADFC [in _Fig._ 28.] represent the Object-glass composed of two Glasses +ABED and BEFC, alike convex on the outsides AGD and CHF, and alike +concave on the insides BME, BNE, with Water in the concavity BMEN. Let +the Sine of Incidence out of Glass into Air be as I to R, and out of +Water into Air, as K to R, and by consequence out of Glass into Water, +as I to K: and let the Diameter of the Sphere to which the convex sides +AGD and CHF are ground be D, and the Diameter of the Sphere to which the +concave sides BME and BNE, are ground be to D, as the Cube Root of +KK--KI to the Cube Root of RK--RI: and the Refractions on the concave +sides of the Glasses, will very much correct the Errors of the +Refractions on the convex sides, so far as they arise from the +sphericalness of the Figure. And by this means might Telescopes be +brought to sufficient perfection, were it not for the different +Refrangibility of several sorts of Rays. But by reason of this different +Refrangibility, I do not yet see any other means of improving Telescopes +by Refractions alone, than that of increasing their lengths, for which +end the late Contrivance of _Hugenius_ seems well accommodated. For very +long Tubes are cumbersome, and scarce to be readily managed, and by +reason of their length are very apt to bend, and shake by bending, so as +to cause a continual trembling in the Objects, whereby it becomes +difficult to see them distinctly: whereas by his Contrivance the Glasses +are readily manageable, and the Object-glass being fix'd upon a strong +upright Pole becomes more steady. + +Seeing therefore the Improvement of Telescopes of given lengths by +Refractions is desperate; I contrived heretofore a Perspective by +Reflexion, using instead of an Object-glass a concave Metal. The +diameter of the Sphere to which the Metal was ground concave was about +25 _English_ Inches, and by consequence the length of the Instrument +about six Inches and a quarter. The Eye-glass was Plano-convex, and the +diameter of the Sphere to which the convex side was ground was about 1/5 +of an Inch, or a little less, and by consequence it magnified between 30 +and 40 times. By another way of measuring I found that it magnified +about 35 times. The concave Metal bore an Aperture of an Inch and a +third part; but the Aperture was limited not by an opake Circle, +covering the Limb of the Metal round about, but by an opake Circle +placed between the Eyeglass and the Eye, and perforated in the middle +with a little round hole for the Rays to pass through to the Eye. For +this Circle by being placed here, stopp'd much of the erroneous Light, +which otherwise would have disturbed the Vision. By comparing it with a +pretty good Perspective of four Feet in length, made with a concave +Eye-glass, I could read at a greater distance with my own Instrument +than with the Glass. Yet Objects appeared much darker in it than in the +Glass, and that partly because more Light was lost by Reflexion in the +Metal, than by Refraction in the Glass, and partly because my Instrument +was overcharged. Had it magnified but 30 or 25 times, it would have made +the Object appear more brisk and pleasant. Two of these I made about 16 +Years ago, and have one of them still by me, by which I can prove the +truth of what I write. Yet it is not so good as at the first. For the +concave has been divers times tarnished and cleared again, by rubbing +it with very soft Leather. When I made these an Artist in _London_ +undertook to imitate it; but using another way of polishing them than I +did, he fell much short of what I had attained to, as I afterwards +understood by discoursing the Under-workman he had employed. The Polish +I used was in this manner. I had two round Copper Plates, each six +Inches in Diameter, the one convex, the other concave, ground very true +to one another. On the convex I ground the Object-Metal or Concave which +was to be polish'd, 'till it had taken the Figure of the Convex and was +ready for a Polish. Then I pitched over the convex very thinly, by +dropping melted Pitch upon it, and warming it to keep the Pitch soft, +whilst I ground it with the concave Copper wetted to make it spread +eavenly all over the convex. Thus by working it well I made it as thin +as a Groat, and after the convex was cold I ground it again to give it +as true a Figure as I could. Then I took Putty which I had made very +fine by washing it from all its grosser Particles, and laying a little +of this upon the Pitch, I ground it upon the Pitch with the concave +Copper, till it had done making a Noise; and then upon the Pitch I +ground the Object-Metal with a brisk motion, for about two or three +Minutes of time, leaning hard upon it. Then I put fresh Putty upon the +Pitch, and ground it again till it had done making a noise, and +afterwards ground the Object-Metal upon it as before. And this Work I +repeated till the Metal was polished, grinding it the last time with all +my strength for a good while together, and frequently breathing upon +the Pitch, to keep it moist without laying on any more fresh Putty. The +Object-Metal was two Inches broad, and about one third part of an Inch +thick, to keep it from bending. I had two of these Metals, and when I +had polished them both, I tried which was best, and ground the other +again, to see if I could make it better than that which I kept. And thus +by many Trials I learn'd the way of polishing, till I made those two +reflecting Perspectives I spake of above. For this Art of polishing will +be better learn'd by repeated Practice than by my Description. Before I +ground the Object-Metal on the Pitch, I always ground the Putty on it +with the concave Copper, till it had done making a noise, because if the +Particles of the Putty were not by this means made to stick fast in the +Pitch, they would by rolling up and down grate and fret the Object-Metal +and fill it full of little holes. + +But because Metal is more difficult to polish than Glass, and is +afterwards very apt to be spoiled by tarnishing, and reflects not so +much Light as Glass quick-silver'd over does: I would propound to use +instead of the Metal, a Glass ground concave on the foreside, and as +much convex on the backside, and quick-silver'd over on the convex side. +The Glass must be every where of the same thickness exactly. Otherwise +it will make Objects look colour'd and indistinct. By such a Glass I +tried about five or six Years ago to make a reflecting Telescope of four +Feet in length to magnify about 150 times, and I satisfied my self that +there wants nothing but a good Artist to bring the Design to +perfection. For the Glass being wrought by one of our _London_ Artists +after such a manner as they grind Glasses for Telescopes, though it +seemed as well wrought as the Object-glasses use to be, yet when it was +quick-silver'd, the Reflexion discovered innumerable Inequalities all +over the Glass. And by reason of these Inequalities, Objects appeared +indistinct in this Instrument. For the Errors of reflected Rays caused +by any Inequality of the Glass, are about six times greater than the +Errors of refracted Rays caused by the like Inequalities. Yet by this +Experiment I satisfied my self that the Reflexion on the concave side of +the Glass, which I feared would disturb the Vision, did no sensible +prejudice to it, and by consequence that nothing is wanting to perfect +these Telescopes, but good Workmen who can grind and polish Glasses +truly spherical. An Object-glass of a fourteen Foot Telescope, made by +an Artificer at _London_, I once mended considerably, by grinding it on +Pitch with Putty, and leaning very easily on it in the grinding, lest +the Putty should scratch it. Whether this way may not do well enough for +polishing these reflecting Glasses, I have not yet tried. But he that +shall try either this or any other way of polishing which he may think +better, may do well to make his Glasses ready for polishing, by grinding +them without that Violence, wherewith our _London_ Workmen press their +Glasses in grinding. For by such violent pressure, Glasses are apt to +bend a little in the grinding, and such bending will certainly spoil +their Figure. To recommend therefore the consideration of these +reflecting Glasses to such Artists as are curious in figuring Glasses, I +shall describe this optical Instrument in the following Proposition. + + +_PROP._ VIII. PROB. II. + +_To shorten Telescopes._ + +Let ABCD [in _Fig._ 29.] represent a Glass spherically concave on the +foreside AB, and as much convex on the backside CD, so that it be every +where of an equal thickness. Let it not be thicker on one side than on +the other, lest it make Objects appear colour'd and indistinct, and let +it be very truly wrought and quick-silver'd over on the backside; and +set in the Tube VXYZ which must be very black within. Let EFG represent +a Prism of Glass or Crystal placed near the other end of the Tube, in +the middle of it, by means of a handle of Brass or Iron FGK, to the end +of which made flat it is cemented. Let this Prism be rectangular at E, +and let the other two Angles at F and G be accurately equal to each +other, and by consequence equal to half right ones, and let the plane +sides FE and GE be square, and by consequence the third side FG a +rectangular Parallelogram, whose length is to its breadth in a +subduplicate proportion of two to one. Let it be so placed in the Tube, +that the Axis of the Speculum may pass through the middle of the square +side EF perpendicularly and by consequence through the middle of the +side FG at an Angle of 45 Degrees, and let the side EF be turned towards +the Speculum, and the distance of this Prism from the Speculum be such +that the Rays of the Light PQ, RS, &c. which are incident upon the +Speculum in Lines parallel to the Axis thereof, may enter the Prism at +the side EF, and be reflected by the side FG, and thence go out of it +through the side GE, to the Point T, which must be the common Focus of +the Speculum ABDC, and of a Plano-convex Eye-glass H, through which +those Rays must pass to the Eye. And let the Rays at their coming out of +the Glass pass through a small round hole, or aperture made in a little +plate of Lead, Brass, or Silver, wherewith the Glass is to be covered, +which hole must be no bigger than is necessary for Light enough to pass +through. For so it will render the Object distinct, the Plate in which +'tis made intercepting all the erroneous part of the Light which comes +from the verges of the Speculum AB. Such an Instrument well made, if it +be six Foot long, (reckoning the length from the Speculum to the Prism, +and thence to the Focus T) will bear an aperture of six Inches at the +Speculum, and magnify between two and three hundred times. But the hole +H here limits the aperture with more advantage, than if the aperture was +placed at the Speculum. If the Instrument be made longer or shorter, the +aperture must be in proportion as the Cube of the square-square Root of +the length, and the magnifying as the aperture. But it's convenient that +the Speculum be an Inch or two broader than the aperture at the least, +and that the Glass of the Speculum be thick, that it bend not in the +working. The Prism EFG must be no bigger than is necessary, and its back +side FG must not be quick-silver'd over. For without quicksilver it will +reflect all the Light incident on it from the Speculum. + +[Illustration: FIG. 29.] + +In this Instrument the Object will be inverted, but may be erected by +making the square sides FF and EG of the Prism EFG not plane but +spherically convex, that the Rays may cross as well before they come at +it as afterwards between it and the Eye-glass. If it be desired that the +Instrument bear a larger aperture, that may be also done by composing +the Speculum of two Glasses with Water between them. + +If the Theory of making Telescopes could at length be fully brought into +Practice, yet there would be certain Bounds beyond which Telescopes +could not perform. For the Air through which we look upon the Stars, is +in a perpetual Tremor; as may be seen by the tremulous Motion of Shadows +cast from high Towers, and by the twinkling of the fix'd Stars. But +these Stars do not twinkle when viewed through Telescopes which have +large apertures. For the Rays of Light which pass through divers parts +of the aperture, tremble each of them apart, and by means of their +various and sometimes contrary Tremors, fall at one and the same time +upon different points in the bottom of the Eye, and their trembling +Motions are too quick and confused to be perceived severally. And all +these illuminated Points constitute one broad lucid Point, composed of +those many trembling Points confusedly and insensibly mixed with one +another by very short and swift Tremors, and thereby cause the Star to +appear broader than it is, and without any trembling of the whole. Long +Telescopes may cause Objects to appear brighter and larger than short +ones can do, but they cannot be so formed as to take away that confusion +of the Rays which arises from the Tremors of the Atmosphere. The only +Remedy is a most serene and quiet Air, such as may perhaps be found on +the tops of the highest Mountains above the grosser Clouds. + +FOOTNOTES: + +[C] _See our_ Author's Lectiones Opticæ § 10. _Sect. II. § 29. and Sect. +III. Prop. 25._ + +[D] See our Author's _Lectiones Opticæ_, Part. I. Sect. 1. §5. + +[E] _This is very fully treated of in our_ Author's Lect. Optic. _Part_ +I. _Sect._ II. + +[F] _See our_ Author's Lect. Optic. Part I. Sect. II. § 29. + +[G] _This is demonstrated in our_ Author's Lect. Optic. _Part_ I. +_Sect._ IV. _Prop._ 37. + +[H] _How to do this, is shewn in our_ Author's Lect. Optic. _Part_ I. +_Sect._ IV. _Prop._ 31. + + + + +THE FIRST BOOK OF OPTICKS + + + + +_PART II._ + + +_PROP._ I. THEOR. I. + +_The Phænomena of Colours in refracted or reflected Light are not caused +by new Modifications of the Light variously impress'd, according to the +various Terminations of the Light and Shadow_. + +The PROOF by Experiments. + +_Exper._ 1. For if the Sun shine into a very dark Chamber through an +oblong hole F, [in _Fig._ 1.] whose breadth is the sixth or eighth part +of an Inch, or something less; and his beam FH do afterwards pass first +through a very large Prism ABC, distant about 20 Feet from the hole, and +parallel to it, and then (with its white part) through an oblong hole H, +whose breadth is about the fortieth or sixtieth part of an Inch, and +which is made in a black opake Body GI, and placed at the distance of +two or three Feet from the Prism, in a parallel Situation both to the +Prism and to the former hole, and if this white Light thus transmitted +through the hole H, fall afterwards upon a white Paper _pt_, placed +after that hole H, at the distance of three or four Feet from it, and +there paint the usual Colours of the Prism, suppose red at _t_, yellow +at _s_, green at _r_, blue at _q_, and violet at _p_; you may with an +Iron Wire, or any such like slender opake Body, whose breadth is about +the tenth part of an Inch, by intercepting the Rays at _k_, _l_, _m_, +_n_ or _o_, take away any one of the Colours at _t_, _s_, _r_, _q_ or +_p_, whilst the other Colours remain upon the Paper as before; or with +an Obstacle something bigger you may take away any two, or three, or +four Colours together, the rest remaining: So that any one of the +Colours as well as violet may become outmost in the Confine of the +Shadow towards _p_, and any one of them as well as red may become +outmost in the Confine of the Shadow towards _t_, and any one of them +may also border upon the Shadow made within the Colours by the Obstacle +R intercepting some intermediate part of the Light; and, lastly, any one +of them by being left alone, may border upon the Shadow on either hand. +All the Colours have themselves indifferently to any Confines of Shadow, +and therefore the differences of these Colours from one another, do not +arise from the different Confines of Shadow, whereby Light is variously +modified, as has hitherto been the Opinion of Philosophers. In trying +these things 'tis to be observed, that by how much the holes F and H are +narrower, and the Intervals between them and the Prism greater, and the +Chamber darker, by so much the better doth the Experiment succeed; +provided the Light be not so far diminished, but that the Colours at +_pt_ be sufficiently visible. To procure a Prism of solid Glass large +enough for this Experiment will be difficult, and therefore a prismatick +Vessel must be made of polish'd Glass Plates cemented together, and +filled with salt Water or clear Oil. + +[Illustration: FIG. 1.] + +_Exper._ 2. The Sun's Light let into a dark Chamber through the round +hole F, [in _Fig._ 2.] half an Inch wide, passed first through the Prism +ABC placed at the hole, and then through a Lens PT something more than +four Inches broad, and about eight Feet distant from the Prism, and +thence converged to O the Focus of the Lens distant from it about three +Feet, and there fell upon a white Paper DE. If that Paper was +perpendicular to that Light incident upon it, as 'tis represented in the +posture DE, all the Colours upon it at O appeared white. But if the +Paper being turned about an Axis parallel to the Prism, became very much +inclined to the Light, as 'tis represented in the Positions _de_ and +_[Greek: de]_; the same Light in the one case appeared yellow and red, +in the other blue. Here one and the same part of the Light in one and +the same place, according to the various Inclinations of the Paper, +appeared in one case white, in another yellow or red, in a third blue, +whilst the Confine of Light and shadow, and the Refractions of the Prism +in all these cases remained the same. + +[Illustration: FIG. 2.] + +[Illustration: FIG. 3.] + +_Exper._ 3. Such another Experiment may be more easily tried as follows. +Let a broad beam of the Sun's Light coming into a dark Chamber through a +hole in the Window-shut be refracted by a large Prism ABC, [in _Fig._ +3.] whose refracting Angle C is more than 60 Degrees, and so soon as it +comes out of the Prism, let it fall upon the white Paper DE glewed upon +a stiff Plane; and this Light, when the Paper is perpendicular to it, as +'tis represented in DE, will appear perfectly white upon the Paper; but +when the Paper is very much inclin'd to it in such a manner as to keep +always parallel to the Axis of the Prism, the whiteness of the whole +Light upon the Paper will according to the inclination of the Paper this +way or that way, change either into yellow and red, as in the posture +_de_, or into blue and violet, as in the posture [Greek: de]. And if the +Light before it fall upon the Paper be twice refracted the same way by +two parallel Prisms, these Colours will become the more conspicuous. +Here all the middle parts of the broad beam of white Light which fell +upon the Paper, did without any Confine of Shadow to modify it, become +colour'd all over with one uniform Colour, the Colour being always the +same in the middle of the Paper as at the edges, and this Colour changed +according to the various Obliquity of the reflecting Paper, without any +change in the Refractions or Shadow, or in the Light which fell upon the +Paper. And therefore these Colours are to be derived from some other +Cause than the new Modifications of Light by Refractions and Shadows. + +If it be asked, what then is their Cause? I answer, That the Paper in +the posture _de_, being more oblique to the more refrangible Rays than +to the less refrangible ones, is more strongly illuminated by the latter +than by the former, and therefore the less refrangible Rays are +predominant in the reflected Light. And where-ever they are predominant +in any Light, they tinge it with red or yellow, as may in some measure +appear by the first Proposition of the first Part of this Book, and will +more fully appear hereafter. And the contrary happens in the posture of +the Paper [Greek: de], the more refrangible Rays being then predominant +which always tinge Light with blues and violets. + +_Exper._ 4. The Colours of Bubbles with which Children play are various, +and change their Situation variously, without any respect to any Confine +or Shadow. If such a Bubble be cover'd with a concave Glass, to keep it +from being agitated by any Wind or Motion of the Air, the Colours will +slowly and regularly change their situation, even whilst the Eye and the +Bubble, and all Bodies which emit any Light, or cast any Shadow, remain +unmoved. And therefore their Colours arise from some regular Cause which +depends not on any Confine of Shadow. What this Cause is will be shewed +in the next Book. + +To these Experiments may be added the tenth Experiment of the first Part +of this first Book, where the Sun's Light in a dark Room being +trajected through the parallel Superficies of two Prisms tied together +in the form of a Parallelopipede, became totally of one uniform yellow +or red Colour, at its emerging out of the Prisms. Here, in the +production of these Colours, the Confine of Shadow can have nothing to +do. For the Light changes from white to yellow, orange and red +successively, without any alteration of the Confine of Shadow: And at +both edges of the emerging Light where the contrary Confines of Shadow +ought to produce different Effects, the Colour is one and the same, +whether it be white, yellow, orange or red: And in the middle of the +emerging Light, where there is no Confine of Shadow at all, the Colour +is the very same as at the edges, the whole Light at its very first +Emergence being of one uniform Colour, whether white, yellow, orange or +red, and going on thence perpetually without any change of Colour, such +as the Confine of Shadow is vulgarly supposed to work in refracted Light +after its Emergence. Neither can these Colours arise from any new +Modifications of the Light by Refractions, because they change +successively from white to yellow, orange and red, while the Refractions +remain the same, and also because the Refractions are made contrary ways +by parallel Superficies which destroy one another's Effects. They arise +not therefore from any Modifications of Light made by Refractions and +Shadows, but have some other Cause. What that Cause is we shewed above +in this tenth Experiment, and need not here repeat it. + +There is yet another material Circumstance of this Experiment. For this +emerging Light being by a third Prism HIK [in _Fig._ 22. _Part_ I.][I] +refracted towards the Paper PT, and there painting the usual Colours of +the Prism, red, yellow, green, blue, violet: If these Colours arose from +the Refractions of that Prism modifying the Light, they would not be in +the Light before its Incidence on that Prism. And yet in that Experiment +we found, that when by turning the two first Prisms about their common +Axis all the Colours were made to vanish but the red; the Light which +makes that red being left alone, appeared of the very same red Colour +before its Incidence on the third Prism. And in general we find by other +Experiments, that when the Rays which differ in Refrangibility are +separated from one another, and any one Sort of them is considered +apart, the Colour of the Light which they compose cannot be changed by +any Refraction or Reflexion whatever, as it ought to be were Colours +nothing else than Modifications of Light caused by Refractions, and +Reflexions, and Shadows. This Unchangeableness of Colour I am now to +describe in the following Proposition. + + +_PROP._ II. THEOR. II. + +_All homogeneal Light has its proper Colour answering to its Degree of +Refrangibility, and that Colour cannot be changed by Reflexions and +Refractions._ + +In the Experiments of the fourth Proposition of the first Part of this +first Book, when I had separated the heterogeneous Rays from one +another, the Spectrum _pt_ formed by the separated Rays, did in the +Progress from its End _p_, on which the most refrangible Rays fell, unto +its other End _t_, on which the least refrangible Rays fell, appear +tinged with this Series of Colours, violet, indigo, blue, green, yellow, +orange, red, together with all their intermediate Degrees in a continual +Succession perpetually varying. So that there appeared as many Degrees +of Colours, as there were sorts of Rays differing in Refrangibility. + +_Exper._ 5. Now, that these Colours could not be changed by Refraction, +I knew by refracting with a Prism sometimes one very little Part of this +Light, sometimes another very little Part, as is described in the +twelfth Experiment of the first Part of this Book. For by this +Refraction the Colour of the Light was never changed in the least. If +any Part of the red Light was refracted, it remained totally of the same +red Colour as before. No orange, no yellow, no green or blue, no other +new Colour was produced by that Refraction. Neither did the Colour any +ways change by repeated Refractions, but continued always the same red +entirely as at first. The like Constancy and Immutability I found also +in the blue, green, and other Colours. So also, if I looked through a +Prism upon any Body illuminated with any part of this homogeneal Light, +as in the fourteenth Experiment of the first Part of this Book is +described; I could not perceive any new Colour generated this way. All +Bodies illuminated with compound Light appear through Prisms confused, +(as was said above) and tinged with various new Colours, but those +illuminated with homogeneal Light appeared through Prisms neither less +distinct, nor otherwise colour'd, than when viewed with the naked Eyes. +Their Colours were not in the least changed by the Refraction of the +interposed Prism. I speak here of a sensible Change of Colour: For the +Light which I here call homogeneal, being not absolutely homogeneal, +there ought to arise some little Change of Colour from its +Heterogeneity. But, if that Heterogeneity was so little as it might be +made by the said Experiments of the fourth Proposition, that Change was +not sensible, and therefore in Experiments, where Sense is Judge, ought +to be accounted none at all. + +_Exper._ 6. And as these Colours were not changeable by Refractions, so +neither were they by Reflexions. For all white, grey, red, yellow, +green, blue, violet Bodies, as Paper, Ashes, red Lead, Orpiment, Indico +Bise, Gold, Silver, Copper, Grass, blue Flowers, Violets, Bubbles of +Water tinged with various Colours, Peacock's Feathers, the Tincture of +_Lignum Nephriticum_, and such-like, in red homogeneal Light appeared +totally red, in blue Light totally blue, in green Light totally green, +and so of other Colours. In the homogeneal Light of any Colour they all +appeared totally of that same Colour, with this only Difference, that +some of them reflected that Light more strongly, others more faintly. I +never yet found any Body, which by reflecting homogeneal Light could +sensibly change its Colour. + +From all which it is manifest, that if the Sun's Light consisted of but +one sort of Rays, there would be but one Colour in the whole World, nor +would it be possible to produce any new Colour by Reflexions and +Refractions, and by consequence that the variety of Colours depends upon +the Composition of Light. + + +_DEFINITION._ + +The homogeneal Light and Rays which appear red, or rather make Objects +appear so, I call Rubrifick or Red-making; those which make Objects +appear yellow, green, blue, and violet, I call Yellow-making, +Green-making, Blue-making, Violet-making, and so of the rest. And if at +any time I speak of Light and Rays as coloured or endued with Colours, I +would be understood to speak not philosophically and properly, but +grossly, and accordingly to such Conceptions as vulgar People in seeing +all these Experiments would be apt to frame. For the Rays to speak +properly are not coloured. In them there is nothing else than a certain +Power and Disposition to stir up a Sensation of this or that Colour. +For as Sound in a Bell or musical String, or other sounding Body, is +nothing but a trembling Motion, and in the Air nothing but that Motion +propagated from the Object, and in the Sensorium 'tis a Sense of that +Motion under the Form of Sound; so Colours in the Object are nothing but +a Disposition to reflect this or that sort of Rays more copiously than +the rest; in the Rays they are nothing but their Dispositions to +propagate this or that Motion into the Sensorium, and in the Sensorium +they are Sensations of those Motions under the Forms of Colours. + + +_PROP._ III. PROB. I. + +_To define the Refrangibility of the several sorts of homogeneal Light +answering to the several Colours._ + +For determining this Problem I made the following Experiment.[J] + +_Exper._ 7. When I had caused the Rectilinear Sides AF, GM, [in _Fig._ +4.] of the Spectrum of Colours made by the Prism to be distinctly +defined, as in the fifth Experiment of the first Part of this Book is +described, there were found in it all the homogeneal Colours in the same +Order and Situation one among another as in the Spectrum of simple +Light, described in the fourth Proposition of that Part. For the Circles +of which the Spectrum of compound Light PT is composed, and which in +the middle Parts of the Spectrum interfere, and are intermix'd with one +another, are not intermix'd in their outmost Parts where they touch +those Rectilinear Sides AF and GM. And therefore, in those Rectilinear +Sides when distinctly defined, there is no new Colour generated by +Refraction. I observed also, that if any where between the two outmost +Circles TMF and PGA a Right Line, as [Greek: gd], was cross to the +Spectrum, so as both Ends to fall perpendicularly upon its Rectilinear +Sides, there appeared one and the same Colour, and degree of Colour from +one End of this Line to the other. I delineated therefore in a Paper the +Perimeter of the Spectrum FAP GMT, and in trying the third Experiment of +the first Part of this Book, I held the Paper so that the Spectrum might +fall upon this delineated Figure, and agree with it exactly, whilst an +Assistant, whose Eyes for distinguishing Colours were more critical than +mine, did by Right Lines [Greek: ab, gd, ez,] &c. drawn cross the +Spectrum, note the Confines of the Colours, that is of the red M[Greek: +ab]F, of the orange [Greek: agdb], of the yellow [Greek: gezd], of the +green [Greek: eêthz], of the blue [Greek: êikth], of the indico [Greek: +ilmk], and of the violet [Greek: l]GA[Greek: m]. And this Operation +being divers times repeated both in the same, and in several Papers, I +found that the Observations agreed well enough with one another, and +that the Rectilinear Sides MG and FA were by the said cross Lines +divided after the manner of a Musical Chord. Let GM be produced to X, +that MX may be equal to GM, and conceive GX, [Greek: l]X, [Greek: i]X, +[Greek: ê]X, [Greek: e]X, [Greek: g]X, [Greek: a]X, MX, to be in +proportion to one another, as the Numbers, 1, 8/9, 5/6, 3/4, 2/3, 3/5, +9/16, 1/2, and so to represent the Chords of the Key, and of a Tone, a +third Minor, a fourth, a fifth, a sixth Major, a seventh and an eighth +above that Key: And the Intervals M[Greek: a], [Greek: ag], [Greek: ge], +[Greek: eê], [Greek: êi], [Greek: il], and [Greek: l]G, will be the +Spaces which the several Colours (red, orange, yellow, green, blue, +indigo, violet) take up. + +[Illustration: FIG. 4.] + +[Illustration: FIG. 5.] + +Now these Intervals or Spaces subtending the Differences of the +Refractions of the Rays going to the Limits of those Colours, that is, +to the Points M, [Greek: a], [Greek: g], [Greek: e], [Greek: ê], [Greek: +i], [Greek: l], G, may without any sensible Error be accounted +proportional to the Differences of the Sines of Refraction of those Rays +having one common Sine of Incidence, and therefore since the common Sine +of Incidence of the most and least refrangible Rays out of Glass into +Air was (by a Method described above) found in proportion to their Sines +of Refraction, as 50 to 77 and 78, divide the Difference between the +Sines of Refraction 77 and 78, as the Line GM is divided by those +Intervals, and you will have 77, 77-1/8, 77-1/5, 77-1/3, 77-1/2, 77-2/3, +77-7/9, 78, the Sines of Refraction of those Rays out of Glass into Air, +their common Sine of Incidence being 50. So then the Sines of the +Incidences of all the red-making Rays out of Glass into Air, were to the +Sines of their Refractions, not greater than 50 to 77, nor less than 50 +to 77-1/8, but they varied from one another according to all +intermediate Proportions. And the Sines of the Incidences of the +green-making Rays were to the Sines of their Refractions in all +Proportions from that of 50 to 77-1/3, unto that of 50 to 77-1/2. And +by the like Limits above-mentioned were the Refractions of the Rays +belonging to the rest of the Colours defined, the Sines of the +red-making Rays extending from 77 to 77-1/8, those of the orange-making +from 77-1/8 to 77-1/5, those of the yellow-making from 77-1/5 to 77-1/3, +those of the green-making from 77-1/3 to 77-1/2, those of the +blue-making from 77-1/2 to 77-2/3, those of the indigo-making from +77-2/3 to 77-7/9, and those of the violet from 77-7/9, to 78. + +These are the Laws of the Refractions made out of Glass into Air, and +thence by the third Axiom of the first Part of this Book, the Laws of +the Refractions made out of Air into Glass are easily derived. + +_Exper._ 8. I found moreover, that when Light goes out of Air through +several contiguous refracting Mediums as through Water and Glass, and +thence goes out again into Air, whether the refracting Superficies be +parallel or inclin'd to one another, that Light as often as by contrary +Refractions 'tis so corrected, that it emergeth in Lines parallel to +those in which it was incident, continues ever after to be white. But if +the emergent Rays be inclined to the incident, the Whiteness of the +emerging Light will by degrees in passing on from the Place of +Emergence, become tinged in its Edges with Colours. This I try'd by +refracting Light with Prisms of Glass placed within a Prismatick Vessel +of Water. Now those Colours argue a diverging and separation of the +heterogeneous Rays from one another by means of their unequal +Refractions, as in what follows will more fully appear. And, on the +contrary, the permanent whiteness argues, that in like Incidences of the +Rays there is no such separation of the emerging Rays, and by +consequence no inequality of their whole Refractions. Whence I seem to +gather the two following Theorems. + +1. The Excesses of the Sines of Refraction of several sorts of Rays +above their common Sine of Incidence when the Refractions are made out +of divers denser Mediums immediately into one and the same rarer Medium, +suppose of Air, are to one another in a given Proportion. + +2. The Proportion of the Sine of Incidence to the Sine of Refraction of +one and the same sort of Rays out of one Medium into another, is +composed of the Proportion of the Sine of Incidence to the Sine of +Refraction out of the first Medium into any third Medium, and of the +Proportion of the Sine of Incidence to the Sine of Refraction out of +that third Medium into the second Medium. + +By the first Theorem the Refractions of the Rays of every sort made out +of any Medium into Air are known by having the Refraction of the Rays of +any one sort. As for instance, if the Refractions of the Rays of every +sort out of Rain-water into Air be desired, let the common Sine of +Incidence out of Glass into Air be subducted from the Sines of +Refraction, and the Excesses will be 27, 27-1/8, 27-1/5, 27-1/3, 27-1/2, +27-2/3, 27-7/9, 28. Suppose now that the Sine of Incidence of the least +refrangible Rays be to their Sine of Refraction out of Rain-water into +Air as 3 to 4, and say as 1 the difference of those Sines is to 3 the +Sine of Incidence, so is 27 the least of the Excesses above-mentioned to +a fourth Number 81; and 81 will be the common Sine of Incidence out of +Rain-water into Air, to which Sine if you add all the above-mentioned +Excesses, you will have the desired Sines of the Refractions 108, +108-1/8, 108-1/5, 108-1/3, 108-1/2, 108-2/3, 108-7/9, 109. + +By the latter Theorem the Refraction out of one Medium into another is +gathered as often as you have the Refractions out of them both into any +third Medium. As if the Sine of Incidence of any Ray out of Glass into +Air be to its Sine of Refraction, as 20 to 31, and the Sine of Incidence +of the same Ray out of Air into Water, be to its Sine of Refraction as 4 +to 3; the Sine of Incidence of that Ray out of Glass into Water will be +to its Sine of Refraction as 20 to 31 and 4 to 3 jointly, that is, as +the Factum of 20 and 4 to the Factum of 31 and 3, or as 80 to 93. + +And these Theorems being admitted into Opticks, there would be scope +enough of handling that Science voluminously after a new manner,[K] not +only by teaching those things which tend to the perfection of Vision, +but also by determining mathematically all kinds of Phænomena of Colours +which could be produced by Refractions. For to do this, there is nothing +else requisite than to find out the Separations of heterogeneous Rays, +and their various Mixtures and Proportions in every Mixture. By this +way of arguing I invented almost all the Phænomena described in these +Books, beside some others less necessary to the Argument; and by the +successes I met with in the Trials, I dare promise, that to him who +shall argue truly, and then try all things with good Glasses and +sufficient Circumspection, the expected Event will not be wanting. But +he is first to know what Colours will arise from any others mix'd in any +assigned Proportion. + + +_PROP._ IV. THEOR. III. + +_Colours may be produced by Composition which shall be like to the +Colours of homogeneal Light as to the Appearance of Colour, but not as +to the Immutability of Colour and Constitution of Light. And those +Colours by how much they are more compounded by so much are they less +full and intense, and by too much Composition they maybe diluted and +weaken'd till they cease, and the Mixture becomes white or grey. There +may be also Colours produced by Composition, which are not fully like +any of the Colours of homogeneal Light._ + +For a Mixture of homogeneal red and yellow compounds an Orange, like in +appearance of Colour to that orange which in the series of unmixed +prismatick Colours lies between them; but the Light of one orange is +homogeneal as to Refrangibility, and that of the other is heterogeneal, +and the Colour of the one, if viewed through a Prism, remains unchanged, +that of the other is changed and resolved into its component Colours red +and yellow. And after the same manner other neighbouring homogeneal +Colours may compound new Colours, like the intermediate homogeneal ones, +as yellow and green, the Colour between them both, and afterwards, if +blue be added, there will be made a green the middle Colour of the three +which enter the Composition. For the yellow and blue on either hand, if +they are equal in quantity they draw the intermediate green equally +towards themselves in Composition, and so keep it as it were in +Æquilibrion, that it verge not more to the yellow on the one hand, and +to the blue on the other, but by their mix'd Actions remain still a +middle Colour. To this mix'd green there may be farther added some red +and violet, and yet the green will not presently cease, but only grow +less full and vivid, and by increasing the red and violet, it will grow +more and more dilute, until by the prevalence of the added Colours it be +overcome and turned into whiteness, or some other Colour. So if to the +Colour of any homogeneal Light, the Sun's white Light composed of all +sorts of Rays be added, that Colour will not vanish or change its +Species, but be diluted, and by adding more and more white it will be +diluted more and more perpetually. Lastly, If red and violet be mingled, +there will be generated according to their various Proportions various +Purples, such as are not like in appearance to the Colour of any +homogeneal Light, and of these Purples mix'd with yellow and blue may be +made other new Colours. + + +_PROP._ V. THEOR. IV. + +_Whiteness and all grey Colours between white and black, may be +compounded of Colours, and the whiteness of the Sun's Light is +compounded of all the primary Colours mix'd in a due Proportion._ + +The PROOF by Experiments. + +_Exper._ 9. The Sun shining into a dark Chamber through a little round +hole in the Window-shut, and his Light being there refracted by a Prism +to cast his coloured Image PT [in _Fig._ 5.] upon the opposite Wall: I +held a white Paper V to that image in such manner that it might be +illuminated by the colour'd Light reflected from thence, and yet not +intercept any part of that Light in its passage from the Prism to the +Spectrum. And I found that when the Paper was held nearer to any Colour +than to the rest, it appeared of that Colour to which it approached +nearest; but when it was equally or almost equally distant from all the +Colours, so that it might be equally illuminated by them all it appeared +white. And in this last situation of the Paper, if some Colours were +intercepted, the Paper lost its white Colour, and appeared of the Colour +of the rest of the Light which was not intercepted. So then the Paper +was illuminated with Lights of various Colours, namely, red, yellow, +green, blue and violet, and every part of the Light retained its proper +Colour, until it was incident on the Paper, and became reflected thence +to the Eye; so that if it had been either alone (the rest of the Light +being intercepted) or if it had abounded most, and been predominant in +the Light reflected from the Paper, it would have tinged the Paper with +its own Colour; and yet being mixed with the rest of the Colours in a +due proportion, it made the Paper look white, and therefore by a +Composition with the rest produced that Colour. The several parts of the +coloured Light reflected from the Spectrum, whilst they are propagated +from thence through the Air, do perpetually retain their proper Colours, +because wherever they fall upon the Eyes of any Spectator, they make the +several parts of the Spectrum to appear under their proper Colours. They +retain therefore their proper Colours when they fall upon the Paper V, +and so by the confusion and perfect mixture of those Colours compound +the whiteness of the Light reflected from thence. + +_Exper._ 10. Let that Spectrum or solar Image PT [in _Fig._ 6.] fall now +upon the Lens MN above four Inches broad, and about six Feet distant +from the Prism ABC and so figured that it may cause the coloured Light +which divergeth from the Prism to converge and meet again at its Focus +G, about six or eight Feet distant from the Lens, and there to fall +perpendicularly upon a white Paper DE. And if you move this Paper to and +fro, you will perceive that near the Lens, as at _de_, the whole solar +Image (suppose at _pt_) will appear upon it intensely coloured after the +manner above-explained, and that by receding from the Lens those Colours +will perpetually come towards one another, and by mixing more and more +dilute one another continually, until at length the Paper come to the +Focus G, where by a perfect mixture they will wholly vanish and be +converted into whiteness, the whole Light appearing now upon the Paper +like a little white Circle. And afterwards by receding farther from the +Lens, the Rays which before converged will now cross one another in the +Focus G, and diverge from thence, and thereby make the Colours to appear +again, but yet in a contrary order; suppose at [Greek: de], where the +red _t_ is now above which before was below, and the violet _p_ is below +which before was above. + +Let us now stop the Paper at the Focus G, where the Light appears +totally white and circular, and let us consider its whiteness. I say, +that this is composed of the converging Colours. For if any of those +Colours be intercepted at the Lens, the whiteness will cease and +degenerate into that Colour which ariseth from the composition of the +other Colours which are not intercepted. And then if the intercepted +Colours be let pass and fall upon that compound Colour, they mix with +it, and by their mixture restore the whiteness. So if the violet, blue +and green be intercepted, the remaining yellow, orange and red will +compound upon the Paper an orange, and then if the intercepted Colours +be let pass, they will fall upon this compounded orange, and together +with it decompound a white. So also if the red and violet be +intercepted, the remaining yellow, green and blue, will compound a green +upon the Paper, and then the red and violet being let pass will fall +upon this green, and together with it decompound a white. And that in +this Composition of white the several Rays do not suffer any Change in +their colorific Qualities by acting upon one another, but are only +mixed, and by a mixture of their Colours produce white, may farther +appear by these Arguments. + +[Illustration: FIG. 6.] + +If the Paper be placed beyond the Focus G, suppose at [Greek: de], and +then the red Colour at the Lens be alternately intercepted, and let pass +again, the violet Colour on the Paper will not suffer any Change +thereby, as it ought to do if the several sorts of Rays acted upon one +another in the Focus G, where they cross. Neither will the red upon the +Paper be changed by any alternate stopping, and letting pass the violet +which crosseth it. + +And if the Paper be placed at the Focus G, and the white round Image at +G be viewed through the Prism HIK, and by the Refraction of that Prism +be translated to the place _rv_, and there appear tinged with various +Colours, namely, the violet at _v_ and red at _r_, and others between, +and then the red Colours at the Lens be often stopp'd and let pass by +turns, the red at _r_ will accordingly disappear, and return as often, +but the violet at _v_ will not thereby suffer any Change. And so by +stopping and letting pass alternately the blue at the Lens, the blue at +_v_ will accordingly disappear and return, without any Change made in +the red at _r_. The red therefore depends on one sort of Rays, and the +blue on another sort, which in the Focus G where they are commix'd, do +not act on one another. And there is the same Reason of the other +Colours. + +I considered farther, that when the most refrangible Rays P_p_, and the +least refrangible ones T_t_, are by converging inclined to one another, +the Paper, if held very oblique to those Rays in the Focus G, might +reflect one sort of them more copiously than the other sort, and by that +Means the reflected Light would be tinged in that Focus with the Colour +of the predominant Rays, provided those Rays severally retained their +Colours, or colorific Qualities in the Composition of White made by them +in that Focus. But if they did not retain them in that White, but became +all of them severally endued there with a Disposition to strike the +Sense with the Perception of White, then they could never lose their +Whiteness by such Reflexions. I inclined therefore the Paper to the Rays +very obliquely, as in the second Experiment of this second Part of the +first Book, that the most refrangible Rays, might be more copiously +reflected than the rest, and the Whiteness at Length changed +successively into blue, indigo, and violet. Then I inclined it the +contrary Way, that the least refrangible Rays might be more copious in +the reflected Light than the rest, and the Whiteness turned successively +to yellow, orange, and red. + +Lastly, I made an Instrument XY in fashion of a Comb, whose Teeth being +in number sixteen, were about an Inch and a half broad, and the +Intervals of the Teeth about two Inches wide. Then by interposing +successively the Teeth of this Instrument near the Lens, I intercepted +Part of the Colours by the interposed Tooth, whilst the rest of them +went on through the Interval of the Teeth to the Paper DE, and there +painted a round Solar Image. But the Paper I had first placed so, that +the Image might appear white as often as the Comb was taken away; and +then the Comb being as was said interposed, that Whiteness by reason of +the intercepted Part of the Colours at the Lens did always change into +the Colour compounded of those Colours which were not intercepted, and +that Colour was by the Motion of the Comb perpetually varied so, that in +the passing of every Tooth over the Lens all these Colours, red, yellow, +green, blue, and purple, did always succeed one another. I caused +therefore all the Teeth to pass successively over the Lens, and when the +Motion was slow, there appeared a perpetual Succession of the Colours +upon the Paper: But if I so much accelerated the Motion, that the +Colours by reason of their quick Succession could not be distinguished +from one another, the Appearance of the single Colours ceased. There was +no red, no yellow, no green, no blue, nor purple to be seen any longer, +but from a Confusion of them all there arose one uniform white Colour. +Of the Light which now by the Mixture of all the Colours appeared white, +there was no Part really white. One Part was red, another yellow, a +third green, a fourth blue, a fifth purple, and every Part retains its +proper Colour till it strike the Sensorium. If the Impressions follow +one another slowly, so that they may be severally perceived, there is +made a distinct Sensation of all the Colours one after another in a +continual Succession. But if the Impressions follow one another so +quickly, that they cannot be severally perceived, there ariseth out of +them all one common Sensation, which is neither of this Colour alone nor +of that alone, but hath it self indifferently to 'em all, and this is a +Sensation of Whiteness. By the Quickness of the Successions, the +Impressions of the several Colours are confounded in the Sensorium, and +out of that Confusion ariseth a mix'd Sensation. If a burning Coal be +nimbly moved round in a Circle with Gyrations continually repeated, the +whole Circle will appear like Fire; the reason of which is, that the +Sensation of the Coal in the several Places of that Circle remains +impress'd on the Sensorium, until the Coal return again to the same +Place. And so in a quick Consecution of the Colours the Impression of +every Colour remains in the Sensorium, until a Revolution of all the +Colours be compleated, and that first Colour return again. The +Impressions therefore of all the successive Colours are at once in the +Sensorium, and jointly stir up a Sensation of them all; and so it is +manifest by this Experiment, that the commix'd Impressions of all the +Colours do stir up and beget a Sensation of white, that is, that +Whiteness is compounded of all the Colours. + +And if the Comb be now taken away, that all the Colours may at once pass +from the Lens to the Paper, and be there intermixed, and together +reflected thence to the Spectator's Eyes; their Impressions on the +Sensorium being now more subtilly and perfectly commixed there, ought +much more to stir up a Sensation of Whiteness. + +You may instead of the Lens use two Prisms HIK and LMN, which by +refracting the coloured Light the contrary Way to that of the first +Refraction, may make the diverging Rays converge and meet again in G, as +you see represented in the seventh Figure. For where they meet and mix, +they will compose a white Light, as when a Lens is used. + +_Exper._ 11. Let the Sun's coloured Image PT [in _Fig._ 8.] fall upon +the Wall of a dark Chamber, as in the third Experiment of the first +Book, and let the same be viewed through a Prism _abc_, held parallel to +the Prism ABC, by whose Refraction that Image was made, and let it now +appear lower than before, suppose in the Place S over-against the red +Colour T. And if you go near to the Image PT, the Spectrum S will appear +oblong and coloured like the Image PT; but if you recede from it, the +Colours of the spectrum S will be contracted more and more, and at +length vanish, that Spectrum S becoming perfectly round and white; and +if you recede yet farther, the Colours will emerge again, but in a +contrary Order. Now that Spectrum S appears white in that Case, when the +Rays of several sorts which converge from the several Parts of the Image +PT, to the Prism _abc_, are so refracted unequally by it, that in their +Passage from the Prism to the Eye they may diverge from one and the same +Point of the Spectrum S, and so fall afterwards upon one and the same +Point in the bottom of the Eye, and there be mingled. + +[Illustration: FIG. 7.] + +[Illustration: FIG. 8.] + +And farther, if the Comb be here made use of, by whose Teeth the Colours +at the Image PT may be successively intercepted; the Spectrum S, when +the Comb is moved slowly, will be perpetually tinged with successive +Colours: But when by accelerating the Motion of the Comb, the Succession +of the Colours is so quick that they cannot be severally seen, that +Spectrum S, by a confused and mix'd Sensation of them all, will appear +white. + +_Exper._ 12. The Sun shining through a large Prism ABC [in _Fig._ 9.] +upon a Comb XY, placed immediately behind the Prism, his Light which +passed through the Interstices of the Teeth fell upon a white Paper DE. +The Breadths of the Teeth were equal to their Interstices, and seven +Teeth together with their Interstices took up an Inch in Breadth. Now, +when the Paper was about two or three Inches distant from the Comb, the +Light which passed through its several Interstices painted so many +Ranges of Colours, _kl_, _mn_, _op_, _qr_, &c. which were parallel to +one another, and contiguous, and without any Mixture of white. And these +Ranges of Colours, if the Comb was moved continually up and down with a +reciprocal Motion, ascended and descended in the Paper, and when the +Motion of the Comb was so quick, that the Colours could not be +distinguished from one another, the whole Paper by their Confusion and +Mixture in the Sensorium appeared white. + +[Illustration: FIG. 9.] + +Let the Comb now rest, and let the Paper be removed farther from the +Prism, and the several Ranges of Colours will be dilated and expanded +into one another more and more, and by mixing their Colours will dilute +one another, and at length, when the distance of the Paper from the Comb +is about a Foot, or a little more (suppose in the Place 2D 2E) they will +so far dilute one another, as to become white. + +With any Obstacle, let all the Light be now stopp'd which passes through +any one Interval of the Teeth, so that the Range of Colours which comes +from thence may be taken away, and you will see the Light of the rest of +the Ranges to be expanded into the Place of the Range taken away, and +there to be coloured. Let the intercepted Range pass on as before, and +its Colours falling upon the Colours of the other Ranges, and mixing +with them, will restore the Whiteness. + +Let the Paper 2D 2E be now very much inclined to the Rays, so that the +most refrangible Rays may be more copiously reflected than the rest, and +the white Colour of the Paper through the Excess of those Rays will be +changed into blue and violet. Let the Paper be as much inclined the +contrary way, that the least refrangible Rays may be now more copiously +reflected than the rest, and by their Excess the Whiteness will be +changed into yellow and red. The several Rays therefore in that white +Light do retain their colorific Qualities, by which those of any sort, +whenever they become more copious than the rest, do by their Excess and +Predominance cause their proper Colour to appear. + +And by the same way of arguing, applied to the third Experiment of this +second Part of the first Book, it may be concluded, that the white +Colour of all refracted Light at its very first Emergence, where it +appears as white as before its Incidence, is compounded of various +Colours. + +[Illustration: FIG. 10.] + +_Exper._ 13. In the foregoing Experiment the several Intervals of the +Teeth of the Comb do the Office of so many Prisms, every Interval +producing the Phænomenon of one Prism. Whence instead of those Intervals +using several Prisms, I try'd to compound Whiteness by mixing their +Colours, and did it by using only three Prisms, as also by using only +two as follows. Let two Prisms ABC and _abc_, [in _Fig._ 10.] whose +refracting Angles B and _b_ are equal, be so placed parallel to one +another, that the refracting Angle B of the one may touch the Angle _c_ +at the Base of the other, and their Planes CB and _cb_, at which the +Rays emerge, may lie in Directum. Then let the Light trajected through +them fall upon the Paper MN, distant about 8 or 12 Inches from the +Prisms. And the Colours generated by the interior Limits B and _c_ of +the two Prisms, will be mingled at PT, and there compound white. For if +either Prism be taken away, the Colours made by the other will appear in +that Place PT, and when the Prism is restored to its Place again, so +that its Colours may there fall upon the Colours of the other, the +Mixture of them both will restore the Whiteness. + +This Experiment succeeds also, as I have tried, when the Angle _b_ of +the lower Prism, is a little greater than the Angle B of the upper, and +between the interior Angles B and _c_, there intercedes some Space B_c_, +as is represented in the Figure, and the refracting Planes BC and _bc_, +are neither in Directum, nor parallel to one another. For there is +nothing more requisite to the Success of this Experiment, than that the +Rays of all sorts may be uniformly mixed upon the Paper in the Place PT. +If the most refrangible Rays coming from the superior Prism take up all +the Space from M to P, the Rays of the same sort which come from the +inferior Prism ought to begin at P, and take up all the rest of the +Space from thence towards N. If the least refrangible Rays coming from +the superior Prism take up the Space MT, the Rays of the same kind which +come from the other Prism ought to begin at T, and take up the +remaining Space TN. If one sort of the Rays which have intermediate +Degrees of Refrangibility, and come from the superior Prism be extended +through the Space MQ, and another sort of those Rays through the Space +MR, and a third sort of them through the Space MS, the same sorts of +Rays coming from the lower Prism, ought to illuminate the remaining +Spaces QN, RN, SN, respectively. And the same is to be understood of all +the other sorts of Rays. For thus the Rays of every sort will be +scattered uniformly and evenly through the whole Space MN, and so being +every where mix'd in the same Proportion, they must every where produce +the same Colour. And therefore, since by this Mixture they produce white +in the Exterior Spaces MP and TN, they must also produce white in the +Interior Space PT. This is the reason of the Composition by which +Whiteness was produced in this Experiment, and by what other way soever +I made the like Composition, the Result was Whiteness. + +Lastly, If with the Teeth of a Comb of a due Size, the coloured Lights +of the two Prisms which fall upon the Space PT be alternately +intercepted, that Space PT, when the Motion of the Comb is slow, will +always appear coloured, but by accelerating the Motion of the Comb so +much that the successive Colours cannot be distinguished from one +another, it will appear white. + +_Exper._ 14. Hitherto I have produced Whiteness by mixing the Colours of +Prisms. If now the Colours of natural Bodies are to be mingled, let +Water a little thicken'd with Soap be agitated to raise a Froth, and +after that Froth has stood a little, there will appear to one that shall +view it intently various Colours every where in the Surfaces of the +several Bubbles; but to one that shall go so far off, that he cannot +distinguish the Colours from one another, the whole Froth will grow +white with a perfect Whiteness. + +_Exper._ 15. Lastly, In attempting to compound a white, by mixing the +coloured Powders which Painters use, I consider'd that all colour'd +Powders do suppress and stop in them a very considerable Part of the +Light by which they are illuminated. For they become colour'd by +reflecting the Light of their own Colours more copiously, and that of +all other Colours more sparingly, and yet they do not reflect the Light +of their own Colours so copiously as white Bodies do. If red Lead, for +instance, and a white Paper, be placed in the red Light of the colour'd +Spectrum made in a dark Chamber by the Refraction of a Prism, as is +described in the third Experiment of the first Part of this Book; the +Paper will appear more lucid than the red Lead, and therefore reflects +the red-making Rays more copiously than red Lead doth. And if they be +held in the Light of any other Colour, the Light reflected by the Paper +will exceed the Light reflected by the red Lead in a much greater +Proportion. And the like happens in Powders of other Colours. And +therefore by mixing such Powders, we are not to expect a strong and +full White, such as is that of Paper, but some dusky obscure one, such +as might arise from a Mixture of Light and Darkness, or from white and +black, that is, a grey, or dun, or russet brown, such as are the Colours +of a Man's Nail, of a Mouse, of Ashes, of ordinary Stones, of Mortar, of +Dust and Dirt in High-ways, and the like. And such a dark white I have +often produced by mixing colour'd Powders. For thus one Part of red +Lead, and five Parts of _Viride Æris_, composed a dun Colour like that +of a Mouse. For these two Colours were severally so compounded of +others, that in both together were a Mixture of all Colours; and there +was less red Lead used than _Viride Æris_, because of the Fulness of its +Colour. Again, one Part of red Lead, and four Parts of blue Bise, +composed a dun Colour verging a little to purple, and by adding to this +a certain Mixture of Orpiment and _Viride Æris_ in a due Proportion, the +Mixture lost its purple Tincture, and became perfectly dun. But the +Experiment succeeded best without Minium thus. To Orpiment I added by +little and little a certain full bright purple, which Painters use, +until the Orpiment ceased to be yellow, and became of a pale red. Then I +diluted that red by adding a little _Viride Æris_, and a little more +blue Bise than _Viride Æris_, until it became of such a grey or pale +white, as verged to no one of the Colours more than to another. For thus +it became of a Colour equal in Whiteness to that of Ashes, or of Wood +newly cut, or of a Man's Skin. The Orpiment reflected more Light than +did any other of the Powders, and therefore conduced more to the +Whiteness of the compounded Colour than they. To assign the Proportions +accurately may be difficult, by reason of the different Goodness of +Powders of the same kind. Accordingly, as the Colour of any Powder is +more or less full and luminous, it ought to be used in a less or greater +Proportion. + +Now, considering that these grey and dun Colours may be also produced by +mixing Whites and Blacks, and by consequence differ from perfect Whites, +not in Species of Colours, but only in degree of Luminousness, it is +manifest that there is nothing more requisite to make them perfectly +white than to increase their Light sufficiently; and, on the contrary, +if by increasing their Light they can be brought to perfect Whiteness, +it will thence also follow, that they are of the same Species of Colour +with the best Whites, and differ from them only in the Quantity of +Light. And this I tried as follows. I took the third of the +above-mention'd grey Mixtures, (that which was compounded of Orpiment, +Purple, Bise, and _Viride Æris_) and rubbed it thickly upon the Floor of +my Chamber, where the Sun shone upon it through the opened Casement; and +by it, in the shadow, I laid a Piece of white Paper of the same Bigness. +Then going from them to the distance of 12 or 18 Feet, so that I could +not discern the Unevenness of the Surface of the Powder, nor the little +Shadows let fall from the gritty Particles thereof; the Powder appeared +intensely white, so as to transcend even the Paper it self in Whiteness, +especially if the Paper were a little shaded from the Light of the +Clouds, and then the Paper compared with the Powder appeared of such a +grey Colour as the Powder had done before. But by laying the Paper where +the Sun shines through the Glass of the Window, or by shutting the +Window that the Sun might shine through the Glass upon the Powder, and +by such other fit Means of increasing or decreasing the Lights wherewith +the Powder and Paper were illuminated, the Light wherewith the Powder is +illuminated may be made stronger in such a due Proportion than the Light +wherewith the Paper is illuminated, that they shall both appear exactly +alike in Whiteness. For when I was trying this, a Friend coming to visit +me, I stopp'd him at the Door, and before I told him what the Colours +were, or what I was doing; I asked him, Which of the two Whites were the +best, and wherein they differed? And after he had at that distance +viewed them well, he answer'd, that they were both good Whites, and that +he could not say which was best, nor wherein their Colours differed. +Now, if you consider, that this White of the Powder in the Sun-shine was +compounded of the Colours which the component Powders (Orpiment, Purple, +Bise, and _Viride Æris_) have in the same Sun-shine, you must +acknowledge by this Experiment, as well as by the former, that perfect +Whiteness may be compounded of Colours. + +From what has been said it is also evident, that the Whiteness of the +Sun's Light is compounded of all the Colours wherewith the several sorts +of Rays whereof that Light consists, when by their several +Refrangibilities they are separated from one another, do tinge Paper or +any other white Body whereon they fall. For those Colours (by _Prop._ +II. _Part_ 2.) are unchangeable, and whenever all those Rays with those +their Colours are mix'd again, they reproduce the same white Light as +before. + + +_PROP._ VI. PROB. II. + +_In a mixture of Primary Colours, the Quantity and Quality of each being +given, to know the Colour of the Compound._ + +[Illustration: FIG. 11.] + +With the Center O [in _Fig._ 11.] and Radius OD describe a Circle ADF, +and distinguish its Circumference into seven Parts DE, EF, FG, GA, AB, +BC, CD, proportional to the seven Musical Tones or Intervals of the +eight Sounds, _Sol_, _la_, _fa_, _sol_, _la_, _mi_, _fa_, _sol_, +contained in an eight, that is, proportional to the Number 1/9, 1/16, +1/10, 1/9, 1/16, 1/16, 1/9. Let the first Part DE represent a red +Colour, the second EF orange, the third FG yellow, the fourth CA green, +the fifth AB blue, the sixth BC indigo, and the seventh CD violet. And +conceive that these are all the Colours of uncompounded Light gradually +passing into one another, as they do when made by Prisms; the +Circumference DEFGABCD, representing the whole Series of Colours from +one end of the Sun's colour'd Image to the other, so that from D to E be +all degrees of red, at E the mean Colour between red and orange, from E +to F all degrees of orange, at F the mean between orange and yellow, +from F to G all degrees of yellow, and so on. Let _p_ be the Center of +Gravity of the Arch DE, and _q_, _r_, _s_, _t_, _u_, _x_, the Centers of +Gravity of the Arches EF, FG, GA, AB, BC, and CD respectively, and about +those Centers of Gravity let Circles proportional to the Number of Rays +of each Colour in the given Mixture be describ'd: that is, the Circle +_p_ proportional to the Number of the red-making Rays in the Mixture, +the Circle _q_ proportional to the Number of the orange-making Rays in +the Mixture, and so of the rest. Find the common Center of Gravity of +all those Circles, _p_, _q_, _r_, _s_, _t_, _u_, _x_. Let that Center be +Z; and from the Center of the Circle ADF, through Z to the +Circumference, drawing the Right Line OY, the Place of the Point Y in +the Circumference shall shew the Colour arising from the Composition of +all the Colours in the given Mixture, and the Line OZ shall be +proportional to the Fulness or Intenseness of the Colour, that is, to +its distance from Whiteness. As if Y fall in the middle between F and G, +the compounded Colour shall be the best yellow; if Y verge from the +middle towards F or G, the compound Colour shall accordingly be a +yellow, verging towards orange or green. If Z fall upon the +Circumference, the Colour shall be intense and florid in the highest +Degree; if it fall in the mid-way between the Circumference and Center, +it shall be but half so intense, that is, it shall be such a Colour as +would be made by diluting the intensest yellow with an equal quantity of +whiteness; and if it fall upon the center O, the Colour shall have lost +all its intenseness, and become a white. But it is to be noted, That if +the point Z fall in or near the line OD, the main ingredients being the +red and violet, the Colour compounded shall not be any of the prismatick +Colours, but a purple, inclining to red or violet, accordingly as the +point Z lieth on the side of the line DO towards E or towards C, and in +general the compounded violet is more bright and more fiery than the +uncompounded. Also if only two of the primary Colours which in the +circle are opposite to one another be mixed in an equal proportion, the +point Z shall fall upon the center O, and yet the Colour compounded of +those two shall not be perfectly white, but some faint anonymous Colour. +For I could never yet by mixing only two primary Colours produce a +perfect white. Whether it may be compounded of a mixture of three taken +at equal distances in the circumference I do not know, but of four or +five I do not much question but it may. But these are Curiosities of +little or no moment to the understanding the Phænomena of Nature. For in +all whites produced by Nature, there uses to be a mixture of all sorts +of Rays, and by consequence a composition of all Colours. + +To give an instance of this Rule; suppose a Colour is compounded of +these homogeneal Colours, of violet one part, of indigo one part, of +blue two parts, of green three parts, of yellow five parts, of orange +six parts, and of red ten parts. Proportional to these parts describe +the Circles _x_, _v_, _t_, _s_, _r_, _q_, _p_, respectively, that is, so +that if the Circle _x_ be one, the Circle _v_ may be one, the Circle _t_ +two, the Circle _s_ three, and the Circles _r_, _q_ and _p_, five, six +and ten. Then I find Z the common center of gravity of these Circles, +and through Z drawing the Line OY, the Point Y falls upon the +circumference between E and F, something nearer to E than to F, and +thence I conclude, that the Colour compounded of these Ingredients will +be an orange, verging a little more to red than to yellow. Also I find +that OZ is a little less than one half of OY, and thence I conclude, +that this orange hath a little less than half the fulness or intenseness +of an uncompounded orange; that is to say, that it is such an orange as +may be made by mixing an homogeneal orange with a good white in the +proportion of the Line OZ to the Line ZY, this Proportion being not of +the quantities of mixed orange and white Powders, but of the quantities +of the Lights reflected from them. + +This Rule I conceive accurate enough for practice, though not +mathematically accurate; and the truth of it may be sufficiently proved +to Sense, by stopping any of the Colours at the Lens in the tenth +Experiment of this Book. For the rest of the Colours which are not +stopp'd, but pass on to the Focus of the Lens, will there compound +either accurately or very nearly such a Colour, as by this Rule ought to +result from their Mixture. + + +_PROP._ VII. THEOR. V. + +_All the Colours in the Universe which are made by Light, and depend not +on the Power of Imagination, are either the Colours of homogeneal +Lights, or compounded of these, and that either accurately or very +nearly, according to the Rule of the foregoing Problem._ + +For it has been proved (in _Prop. 1. Part 2._) that the changes of +Colours made by Refractions do not arise from any new Modifications of +the Rays impress'd by those Refractions, and by the various Terminations +of Light and Shadow, as has been the constant and general Opinion of +Philosophers. It has also been proved that the several Colours of the +homogeneal Rays do constantly answer to their degrees of Refrangibility, +(_Prop._ 1. _Part_ 1. and _Prop._ 2. _Part_ 2.) and that their degrees +of Refrangibility cannot be changed by Refractions and Reflexions +(_Prop._ 2. _Part_ 1.) and by consequence that those their Colours are +likewise immutable. It has also been proved directly by refracting and +reflecting homogeneal Lights apart, that their Colours cannot be +changed, (_Prop._ 2. _Part_ 2.) It has been proved also, that when the +several sorts of Rays are mixed, and in crossing pass through the same +space, they do not act on one another so as to change each others +colorific qualities. (_Exper._ 10. _Part_ 2.) but by mixing their +Actions in the Sensorium beget a Sensation differing from what either +would do apart, that is a Sensation of a mean Colour between their +proper Colours; and particularly when by the concourse and mixtures of +all sorts of Rays, a white Colour is produced, the white is a mixture of +all the Colours which the Rays would have apart, (_Prop._ 5. _Part_ 2.) +The Rays in that mixture do not lose or alter their several colorific +qualities, but by all their various kinds of Actions mix'd in the +Sensorium, beget a Sensation of a middling Colour between all their +Colours, which is whiteness. For whiteness is a mean between all +Colours, having it self indifferently to them all, so as with equal +facility to be tinged with any of them. A red Powder mixed with a little +blue, or a blue with a little red, doth not presently lose its Colour, +but a white Powder mix'd with any Colour is presently tinged with that +Colour, and is equally capable of being tinged with any Colour whatever. +It has been shewed also, that as the Sun's Light is mix'd of all sorts +of Rays, so its whiteness is a mixture of the Colours of all sorts of +Rays; those Rays having from the beginning their several colorific +qualities as well as their several Refrangibilities, and retaining them +perpetually unchanged notwithstanding any Refractions or Reflexions they +may at any time suffer, and that whenever any sort of the Sun's Rays is +by any means (as by Reflexion in _Exper._ 9, and 10. _Part_ 1. or by +Refraction as happens in all Refractions) separated from the rest, they +then manifest their proper Colours. These things have been prov'd, and +the sum of all this amounts to the Proposition here to be proved. For if +the Sun's Light is mix'd of several sorts of Rays, each of which have +originally their several Refrangibilities and colorific Qualities, and +notwithstanding their Refractions and Reflexions, and their various +Separations or Mixtures, keep those their original Properties +perpetually the same without alteration; then all the Colours in the +World must be such as constantly ought to arise from the original +colorific qualities of the Rays whereof the Lights consist by which +those Colours are seen. And therefore if the reason of any Colour +whatever be required, we have nothing else to do than to consider how +the Rays in the Sun's Light have by Reflexions or Refractions, or other +causes, been parted from one another, or mixed together; or otherwise to +find out what sorts of Rays are in the Light by which that Colour is +made, and in what Proportion; and then by the last Problem to learn the +Colour which ought to arise by mixing those Rays (or their Colours) in +that proportion. I speak here of Colours so far as they arise from +Light. For they appear sometimes by other Causes, as when by the power +of Phantasy we see Colours in a Dream, or a Mad-man sees things before +him which are not there; or when we see Fire by striking the Eye, or see +Colours like the Eye of a Peacock's Feather, by pressing our Eyes in +either corner whilst we look the other way. Where these and such like +Causes interpose not, the Colour always answers to the sort or sorts of +the Rays whereof the Light consists, as I have constantly found in +whatever Phænomena of Colours I have hitherto been able to examine. I +shall in the following Propositions give instances of this in the +Phænomena of chiefest note. + + +_PROP._ VIII. PROB. III. + +_By the discovered Properties of Light to explain the Colours made by +Prisms._ + +Let ABC [in _Fig._ 12.] represent a Prism refracting the Light of the +Sun, which comes into a dark Chamber through a hole F[Greek: ph] almost +as broad as the Prism, and let MN represent a white Paper on which the +refracted Light is cast, and suppose the most refrangible or deepest +violet-making Rays fall upon the Space P[Greek: p], the least +refrangible or deepest red-making Rays upon the Space T[Greek: t], the +middle sort between the indigo-making and blue-making Rays upon the +Space Q[Greek: ch], the middle sort of the green-making Rays upon the +Space R, the middle sort between the yellow-making and orange-making +Rays upon the Space S[Greek: s], and other intermediate sorts upon +intermediate Spaces. For so the Spaces upon which the several sorts +adequately fall will by reason of the different Refrangibility of those +sorts be one lower than another. Now if the Paper MN be so near the +Prism that the Spaces PT and [Greek: pt] do not interfere with one +another, the distance between them T[Greek: p] will be illuminated by +all the sorts of Rays in that proportion to one another which they have +at their very first coming out of the Prism, and consequently be white. +But the Spaces PT and [Greek: pt] on either hand, will not be +illuminated by them all, and therefore will appear coloured. And +particularly at P, where the outmost violet-making Rays fall alone, the +Colour must be the deepest violet. At Q where the violet-making and +indigo-making Rays are mixed, it must be a violet inclining much to +indigo. At R where the violet-making, indigo-making, blue-making, and +one half of the green-making Rays are mixed, their Colours must (by the +construction of the second Problem) compound a middle Colour between +indigo and blue. At S where all the Rays are mixed, except the +red-making and orange-making, their Colours ought by the same Rule to +compound a faint blue, verging more to green than indigo. And in the +progress from S to T, this blue will grow more and more faint and +dilute, till at T, where all the Colours begin to be mixed, it ends in +whiteness. + +[Illustration: FIG. 12.] + +So again, on the other side of the white at [Greek: t], where the least +refrangible or utmost red-making Rays are alone, the Colour must be the +deepest red. At [Greek: s] the mixture of red and orange will compound a +red inclining to orange. At [Greek: r] the mixture of red, orange, +yellow, and one half of the green must compound a middle Colour between +orange and yellow. At [Greek: ch] the mixture of all Colours but violet +and indigo will compound a faint yellow, verging more to green than to +orange. And this yellow will grow more faint and dilute continually in +its progress from [Greek: ch] to [Greek: p], where by a mixture of all +sorts of Rays it will become white. + +These Colours ought to appear were the Sun's Light perfectly white: But +because it inclines to yellow, the Excess of the yellow-making Rays +whereby 'tis tinged with that Colour, being mixed with the faint blue +between S and T, will draw it to a faint green. And so the Colours in +order from P to [Greek: t] ought to be violet, indigo, blue, very faint +green, white, faint yellow, orange, red. Thus it is by the computation: +And they that please to view the Colours made by a Prism will find it so +in Nature. + +These are the Colours on both sides the white when the Paper is held +between the Prism and the Point X where the Colours meet, and the +interjacent white vanishes. For if the Paper be held still farther off +from the Prism, the most refrangible and least refrangible Rays will be +wanting in the middle of the Light, and the rest of the Rays which are +found there, will by mixture produce a fuller green than before. Also +the yellow and blue will now become less compounded, and by consequence +more intense than before. And this also agrees with experience. + +And if one look through a Prism upon a white Object encompassed with +blackness or darkness, the reason of the Colours arising on the edges is +much the same, as will appear to one that shall a little consider it. If +a black Object be encompassed with a white one, the Colours which appear +through the Prism are to be derived from the Light of the white one, +spreading into the Regions of the black, and therefore they appear in a +contrary order to that, when a white Object is surrounded with black. +And the same is to be understood when an Object is viewed, whose parts +are some of them less luminous than others. For in the borders of the +more and less luminous Parts, Colours ought always by the same +Principles to arise from the Excess of the Light of the more luminous, +and to be of the same kind as if the darker parts were black, but yet to +be more faint and dilute. + +What is said of Colours made by Prisms may be easily applied to Colours +made by the Glasses of Telescopes or Microscopes, or by the Humours of +the Eye. For if the Object-glass of a Telescope be thicker on one side +than on the other, or if one half of the Glass, or one half of the Pupil +of the Eye be cover'd with any opake substance; the Object-glass, or +that part of it or of the Eye which is not cover'd, may be consider'd as +a Wedge with crooked Sides, and every Wedge of Glass or other pellucid +Substance has the effect of a Prism in refracting the Light which passes +through it.[L] + +How the Colours in the ninth and tenth Experiments of the first Part +arise from the different Reflexibility of Light, is evident by what was +there said. But it is observable in the ninth Experiment, that whilst +the Sun's direct Light is yellow, the Excess of the blue-making Rays in +the reflected beam of Light MN, suffices only to bring that yellow to a +pale white inclining to blue, and not to tinge it with a manifestly blue +Colour. To obtain therefore a better blue, I used instead of the yellow +Light of the Sun the white Light of the Clouds, by varying a little the +Experiment, as follows. + +[Illustration: FIG. 13.] + +_Exper._ 16 Let HFG [in _Fig._ 13.] represent a Prism in the open Air, +and S the Eye of the Spectator, viewing the Clouds by their Light coming +into the Prism at the Plane Side FIGK, and reflected in it by its Base +HEIG, and thence going out through its Plane Side HEFK to the Eye. And +when the Prism and Eye are conveniently placed, so that the Angles of +Incidence and Reflexion at the Base may be about 40 Degrees, the +Spectator will see a Bow MN of a blue Colour, running from one End of +the Base to the other, with the Concave Side towards him, and the Part +of the Base IMNG beyond this Bow will be brighter than the other Part +EMNH on the other Side of it. This blue Colour MN being made by nothing +else than by Reflexion of a specular Superficies, seems so odd a +Phænomenon, and so difficult to be explained by the vulgar Hypothesis of +Philosophers, that I could not but think it deserved to be taken Notice +of. Now for understanding the Reason of it, suppose the Plane ABC to cut +the Plane Sides and Base of the Prism perpendicularly. From the Eye to +the Line BC, wherein that Plane cuts the Base, draw the Lines S_p_ and +S_t_, in the Angles S_pc_ 50 degr. 1/9, and S_tc_ 49 degr. 1/28, and the +Point _p_ will be the Limit beyond which none of the most refrangible +Rays can pass through the Base of the Prism, and be refracted, whose +Incidence is such that they may be reflected to the Eye; and the Point +_t_ will be the like Limit for the least refrangible Rays, that is, +beyond which none of them can pass through the Base, whose Incidence is +such that by Reflexion they may come to the Eye. And the Point _r_ taken +in the middle Way between _p_ and _t_, will be the like Limit for the +meanly refrangible Rays. And therefore all the least refrangible Rays +which fall upon the Base beyond _t_, that is, between _t_ and B, and can +come from thence to the Eye, will be reflected thither: But on this side +_t_, that is, between _t_ and _c_, many of these Rays will be +transmitted through the Base. And all the most refrangible Rays which +fall upon the Base beyond _p_, that is, between, _p_ and B, and can by +Reflexion come from thence to the Eye, will be reflected thither, but +every where between _p_ and _c_, many of these Rays will get through the +Base, and be refracted; and the same is to be understood of the meanly +refrangible Rays on either side of the Point _r_. Whence it follows, +that the Base of the Prism must every where between _t_ and B, by a +total Reflexion of all sorts of Rays to the Eye, look white and bright. +And every where between _p_ and C, by reason of the Transmission of many +Rays of every sort, look more pale, obscure, and dark. But at _r_, and +in other Places between _p_ and _t_, where all the more refrangible Rays +are reflected to the Eye, and many of the less refrangible are +transmitted, the Excess of the most refrangible in the reflected Light +will tinge that Light with their Colour, which is violet and blue. And +this happens by taking the Line C _prt_ B any where between the Ends of +the Prism HG and EI. + + +_PROP._ IX. PROB. IV. + +_By the discovered Properties of Light to explain the Colours of the +Rain-bow._ + +[Illustration: FIG. 14.] + +This Bow never appears, but where it rains in the Sun-shine, and may be +made artificially by spouting up Water which may break aloft, and +scatter into Drops, and fall down like Rain. For the Sun shining upon +these Drops certainly causes the Bow to appear to a Spectator standing +in a due Position to the Rain and Sun. And hence it is now agreed upon, +that this Bow is made by Refraction of the Sun's Light in drops of +falling Rain. This was understood by some of the Antients, and of late +more fully discover'd and explain'd by the famous _Antonius de Dominis_ +Archbishop of _Spalato_, in his book _De Radiis Visûs & Lucis_, +published by his Friend _Bartolus_ at _Venice_, in the Year 1611, and +written above 20 Years before. For he teaches there how the interior Bow +is made in round Drops of Rain by two Refractions of the Sun's Light, +and one Reflexion between them, and the exterior by two Refractions, and +two sorts of Reflexions between them in each Drop of Water, and proves +his Explications by Experiments made with a Phial full of Water, and +with Globes of Glass filled with Water, and placed in the Sun to make +the Colours of the two Bows appear in them. The same Explication +_Des-Cartes_ hath pursued in his Meteors, and mended that of the +exterior Bow. But whilst they understood not the true Origin of Colours, +it's necessary to pursue it here a little farther. For understanding +therefore how the Bow is made, let a Drop of Rain, or any other +spherical transparent Body be represented by the Sphere BNFG, [in _Fig._ +14.] described with the Center C, and Semi-diameter CN. And let AN be +one of the Sun's Rays incident upon it at N, and thence refracted to F, +where let it either go out of the Sphere by Refraction towards V, or be +reflected to G; and at G let it either go out by Refraction to R, or be +reflected to H; and at H let it go out by Refraction towards S, cutting +the incident Ray in Y. Produce AN and RG, till they meet in X, and upon +AX and NF, let fall the Perpendiculars CD and CE, and produce CD till it +fall upon the Circumference at L. Parallel to the incident Ray AN draw +the Diameter BQ, and let the Sine of Incidence out of Air into Water be +to the Sine of Refraction as I to R. Now, if you suppose the Point of +Incidence N to move from the Point B, continually till it come to L, the +Arch QF will first increase and then decrease, and so will the Angle AXR +which the Rays AN and GR contain; and the Arch QF and Angle AXR will be +biggest when ND is to CN as sqrt(II - RR) to sqrt(3)RR, in which +case NE will be to ND as 2R to I. Also the Angle AYS, which the Rays AN +and HS contain will first decrease, and then increase and grow least +when ND is to CN as sqrt(II - RR) to sqrt(8)RR, in which case NE +will be to ND, as 3R to I. And so the Angle which the next emergent Ray +(that is, the emergent Ray after three Reflexions) contains with the +incident Ray AN will come to its Limit when ND is to CN as sqrt(II - +RR) to sqrt(15)RR, in which case NE will be to ND as 4R to I. And the +Angle which the Ray next after that Emergent, that is, the Ray emergent +after four Reflexions, contains with the Incident, will come to its +Limit, when ND is to CN as sqrt(II - RR) to sqrt(24)RR, in which +case NE will be to ND as 5R to I; and so on infinitely, the Numbers 3, +8, 15, 24, &c. being gather'd by continual Addition of the Terms of the +arithmetical Progression 3, 5, 7, 9, &c. The Truth of all this +Mathematicians will easily examine.[M] + +Now it is to be observed, that as when the Sun comes to his Tropicks, +Days increase and decrease but a very little for a great while together; +so when by increasing the distance CD, these Angles come to their +Limits, they vary their quantity but very little for some time together, +and therefore a far greater number of the Rays which fall upon all the +Points N in the Quadrant BL, shall emerge in the Limits of these Angles, +than in any other Inclinations. And farther it is to be observed, that +the Rays which differ in Refrangibility will have different Limits of +their Angles of Emergence, and by consequence according to their +different Degrees of Refrangibility emerge most copiously in different +Angles, and being separated from one another appear each in their proper +Colours. And what those Angles are may be easily gather'd from the +foregoing Theorem by Computation. + +For in the least refrangible Rays the Sines I and R (as was found above) +are 108 and 81, and thence by Computation the greatest Angle AXR will be +found 42 Degrees and 2 Minutes, and the least Angle AYS, 50 Degrees and +57 Minutes. And in the most refrangible Rays the Sines I and R are 109 +and 81, and thence by Computation the greatest Angle AXR will be found +40 Degrees and 17 Minutes, and the least Angle AYS 54 Degrees and 7 +Minutes. + +Suppose now that O [in _Fig._ 15.] is the Spectator's Eye, and OP a Line +drawn parallel to the Sun's Rays and let POE, POF, POG, POH, be Angles +of 40 Degr. 17 Min. 42 Degr. 2 Min. 50 Degr. 57 Min. and 54 Degr. 7 Min. +respectively, and these Angles turned about their common Side OP, shall +with their other Sides OE, OF; OG, OH, describe the Verges of two +Rain-bows AF, BE and CHDG. For if E, F, G, H, be drops placed any where +in the conical Superficies described by OE, OF, OG, OH, and be +illuminated by the Sun's Rays SE, SF, SG, SH; the Angle SEO being equal +to the Angle POE, or 40 Degr. 17 Min. shall be the greatest Angle in +which the most refrangible Rays can after one Reflexion be refracted to +the Eye, and therefore all the Drops in the Line OE shall send the most +refrangible Rays most copiously to the Eye, and thereby strike the +Senses with the deepest violet Colour in that Region. And in like +manner the Angle SFO being equal to the Angle POF, or 42 Degr. 2 Min. +shall be the greatest in which the least refrangible Rays after one +Reflexion can emerge out of the Drops, and therefore those Rays shall +come most copiously to the Eye from the Drops in the Line OF, and strike +the Senses with the deepest red Colour in that Region. And by the same +Argument, the Rays which have intermediate Degrees of Refrangibility +shall come most copiously from Drops between E and F, and strike the +Senses with the intermediate Colours, in the Order which their Degrees +of Refrangibility require, that is in the Progress from E to F, or from +the inside of the Bow to the outside in this order, violet, indigo, +blue, green, yellow, orange, red. But the violet, by the mixture of the +white Light of the Clouds, will appear faint and incline to purple. + +[Illustration: FIG. 15.] + +Again, the Angle SGO being equal to the Angle POG, or 50 Gr. 51 Min. +shall be the least Angle in which the least refrangible Rays can after +two Reflexions emerge out of the Drops, and therefore the least +refrangible Rays shall come most copiously to the Eye from the Drops in +the Line OG, and strike the Sense with the deepest red in that Region. +And the Angle SHO being equal to the Angle POH, or 54 Gr. 7 Min. shall +be the least Angle, in which the most refrangible Rays after two +Reflexions can emerge out of the Drops; and therefore those Rays shall +come most copiously to the Eye from the Drops in the Line OH, and strike +the Senses with the deepest violet in that Region. And by the same +Argument, the Drops in the Regions between G and H shall strike the +Sense with the intermediate Colours in the Order which their Degrees of +Refrangibility require, that is, in the Progress from G to H, or from +the inside of the Bow to the outside in this order, red, orange, yellow, +green, blue, indigo, violet. And since these four Lines OE, OF, OG, OH, +may be situated any where in the above-mention'd conical Superficies; +what is said of the Drops and Colours in these Lines is to be understood +of the Drops and Colours every where in those Superficies. + +Thus shall there be made two Bows of Colours, an interior and stronger, +by one Reflexion in the Drops, and an exterior and fainter by two; for +the Light becomes fainter by every Reflexion. And their Colours shall +lie in a contrary Order to one another, the red of both Bows bordering +upon the Space GF, which is between the Bows. The Breadth of the +interior Bow EOF measured cross the Colours shall be 1 Degr. 45 Min. and +the Breadth of the exterior GOH shall be 3 Degr. 10 Min. and the +distance between them GOF shall be 8 Gr. 15 Min. the greatest +Semi-diameter of the innermost, that is, the Angle POF being 42 Gr. 2 +Min. and the least Semi-diameter of the outermost POG, being 50 Gr. 57 +Min. These are the Measures of the Bows, as they would be were the Sun +but a Point; for by the Breadth of his Body, the Breadth of the Bows +will be increased, and their Distance decreased by half a Degree, and so +the breadth of the interior Iris will be 2 Degr. 15 Min. that of the +exterior 3 Degr. 40 Min. their distance 8 Degr. 25 Min. the greatest +Semi-diameter of the interior Bow 42 Degr. 17 Min. and the least of the +exterior 50 Degr. 42 Min. And such are the Dimensions of the Bows in the +Heavens found to be very nearly, when their Colours appear strong and +perfect. For once, by such means as I then had, I measured the greatest +Semi-diameter of the interior Iris about 42 Degrees, and the breadth of +the red, yellow and green in that Iris 63 or 64 Minutes, besides the +outmost faint red obscured by the brightness of the Clouds, for which we +may allow 3 or 4 Minutes more. The breadth of the blue was about 40 +Minutes more besides the violet, which was so much obscured by the +brightness of the Clouds, that I could not measure its breadth. But +supposing the breadth of the blue and violet together to equal that of +the red, yellow and green together, the whole breadth of this Iris will +be about 2-1/4 Degrees, as above. The least distance between this Iris +and the exterior Iris was about 8 Degrees and 30 Minutes. The exterior +Iris was broader than the interior, but so faint, especially on the blue +side, that I could not measure its breadth distinctly. At another time +when both Bows appeared more distinct, I measured the breadth of the +interior Iris 2 Gr. 10´, and the breadth of the red, yellow and green in +the exterior Iris, was to the breadth of the same Colours in the +interior as 3 to 2. + +This Explication of the Rain-bow is yet farther confirmed by the known +Experiment (made by _Antonius de Dominis_ and _Des-Cartes_) of hanging +up any where in the Sun-shine a Glass Globe filled with Water, and +viewing it in such a posture, that the Rays which come from the Globe to +the Eye may contain with the Sun's Rays an Angle of either 42 or 50 +Degrees. For if the Angle be about 42 or 43 Degrees, the Spectator +(suppose at O) shall see a full red Colour in that side of the Globe +opposed to the Sun as 'tis represented at F, and if that Angle become +less (suppose by depressing the Globe to E) there will appear other +Colours, yellow, green and blue successive in the same side of the +Globe. But if the Angle be made about 50 Degrees (suppose by lifting up +the Globe to G) there will appear a red Colour in that side of the Globe +towards the Sun, and if the Angle be made greater (suppose by lifting +up the Globe to H) the red will turn successively to the other Colours, +yellow, green and blue. The same thing I have tried, by letting a Globe +rest, and raising or depressing the Eye, or otherwise moving it to make +the Angle of a just magnitude. + +I have heard it represented, that if the Light of a Candle be refracted +by a Prism to the Eye; when the blue Colour falls upon the Eye, the +Spectator shall see red in the Prism, and when the red falls upon the +Eye he shall see blue; and if this were certain, the Colours of the +Globe and Rain-bow ought to appear in a contrary order to what we find. +But the Colours of the Candle being very faint, the mistake seems to +arise from the difficulty of discerning what Colours fall on the Eye. +For, on the contrary, I have sometimes had occasion to observe in the +Sun's Light refracted by a Prism, that the Spectator always sees that +Colour in the Prism which falls upon his Eye. And the same I have found +true also in Candle-light. For when the Prism is moved slowly from the +Line which is drawn directly from the Candle to the Eye, the red appears +first in the Prism and then the blue, and therefore each of them is seen +when it falls upon the Eye. For the red passes over the Eye first, and +then the blue. + +The Light which comes through drops of Rain by two Refractions without +any Reflexion, ought to appear strongest at the distance of about 26 +Degrees from the Sun, and to decay gradually both ways as the distance +from him increases and decreases. And the same is to be understood of +Light transmitted through spherical Hail-stones. And if the Hail be a +little flatted, as it often is, the Light transmitted may grow so strong +at a little less distance than that of 26 Degrees, as to form a Halo +about the Sun or Moon; which Halo, as often as the Hail-stones are duly +figured may be colour'd, and then it must be red within by the least +refrangible Rays, and blue without by the most refrangible ones, +especially if the Hail-stones have opake Globules of Snow in their +center to intercept the Light within the Halo (as _Hugenius_ has +observ'd) and make the inside thereof more distinctly defined than it +would otherwise be. For such Hail-stones, though spherical, by +terminating the Light by the Snow, may make a Halo red within and +colourless without, and darker in the red than without, as Halos used to +be. For of those Rays which pass close by the Snow the Rubriform will be +least refracted, and so come to the Eye in the directest Lines. + +The Light which passes through a drop of Rain after two Refractions, and +three or more Reflexions, is scarce strong enough to cause a sensible +Bow; but in those Cylinders of Ice by which _Hugenius_ explains the +_Parhelia_, it may perhaps be sensible. + + +_PROP._ X. PROB. V. + +_By the discovered Properties of Light to explain the permanent Colours +of Natural Bodies._ + +These Colours arise from hence, that some natural Bodies reflect some +sorts of Rays, others other sorts more copiously than the rest. Minium +reflects the least refrangible or red-making Rays most copiously, and +thence appears red. Violets reflect the most refrangible most copiously, +and thence have their Colour, and so of other Bodies. Every Body +reflects the Rays of its own Colour more copiously than the rest, and +from their excess and predominance in the reflected Light has its +Colour. + +_Exper._ 17. For if in the homogeneal Lights obtained by the solution of +the Problem proposed in the fourth Proposition of the first Part of this +Book, you place Bodies of several Colours, you will find, as I have +done, that every Body looks most splendid and luminous in the Light of +its own Colour. Cinnaber in the homogeneal red Light is most +resplendent, in the green Light it is manifestly less resplendent, and +in the blue Light still less. Indigo in the violet blue Light is most +resplendent, and its splendor is gradually diminish'd, as it is removed +thence by degrees through the green and yellow Light to the red. By a +Leek the green Light, and next that the blue and yellow which compound +green, are more strongly reflected than the other Colours red and +violet, and so of the rest. But to make these Experiments the more +manifest, such Bodies ought to be chosen as have the fullest and most +vivid Colours, and two of those Bodies are to be compared together. +Thus, for instance, if Cinnaber and _ultra_-marine blue, or some other +full blue be held together in the red homogeneal Light, they will both +appear red, but the Cinnaber will appear of a strongly luminous and +resplendent red, and the _ultra_-marine blue of a faint obscure and dark +red; and if they be held together in the blue homogeneal Light, they +will both appear blue, but the _ultra_-marine will appear of a strongly +luminous and resplendent blue, and the Cinnaber of a faint and dark +blue. Which puts it out of dispute that the Cinnaber reflects the red +Light much more copiously than the _ultra_-marine doth, and the +_ultra_-marine reflects the blue Light much more copiously than the +Cinnaber doth. The same Experiment may be tried successfully with red +Lead and Indigo, or with any other two colour'd Bodies, if due allowance +be made for the different strength or weakness of their Colour and +Light. + +And as the reason of the Colours of natural Bodies is evident by these +Experiments, so it is farther confirmed and put past dispute by the two +first Experiments of the first Part, whereby 'twas proved in such Bodies +that the reflected Lights which differ in Colours do differ also in +degrees of Refrangibility. For thence it's certain, that some Bodies +reflect the more refrangible, others the less refrangible Rays more +copiously. + +And that this is not only a true reason of these Colours, but even the +only reason, may appear farther from this Consideration, that the Colour +of homogeneal Light cannot be changed by the Reflexion of natural +Bodies. + +For if Bodies by Reflexion cannot in the least change the Colour of any +one sort of Rays, they cannot appear colour'd by any other means than by +reflecting those which either are of their own Colour, or which by +mixture must produce it. + +But in trying Experiments of this kind care must be had that the Light +be sufficiently homogeneal. For if Bodies be illuminated by the ordinary +prismatick Colours, they will appear neither of their own Day-light +Colours, nor of the Colour of the Light cast on them, but of some middle +Colour between both, as I have found by Experience. Thus red Lead (for +instance) illuminated with the ordinary prismatick green will not appear +either red or green, but orange or yellow, or between yellow and green, +accordingly as the green Light by which 'tis illuminated is more or less +compounded. For because red Lead appears red when illuminated with white +Light, wherein all sorts of Rays are equally mix'd, and in the green +Light all sorts of Rays are not equally mix'd, the Excess of the +yellow-making, green-making and blue-making Rays in the incident green +Light, will cause those Rays to abound so much in the reflected Light, +as to draw the Colour from red towards their Colour. And because the red +Lead reflects the red-making Rays most copiously in proportion to their +number, and next after them the orange-making and yellow-making Rays; +these Rays in the reflected Light will be more in proportion to the +Light than they were in the incident green Light, and thereby will draw +the reflected Light from green towards their Colour. And therefore the +red Lead will appear neither red nor green, but of a Colour between +both. + +In transparently colour'd Liquors 'tis observable, that their Colour +uses to vary with their thickness. Thus, for instance, a red Liquor in a +conical Glass held between the Light and the Eye, looks of a pale and +dilute yellow at the bottom where 'tis thin, and a little higher where +'tis thicker grows orange, and where 'tis still thicker becomes red, and +where 'tis thickest the red is deepest and darkest. For it is to be +conceiv'd that such a Liquor stops the indigo-making and violet-making +Rays most easily, the blue-making Rays more difficultly, the +green-making Rays still more difficultly, and the red-making most +difficultly: And that if the thickness of the Liquor be only so much as +suffices to stop a competent number of the violet-making and +indigo-making Rays, without diminishing much the number of the rest, the +rest must (by _Prop._ 6. _Part_ 2.) compound a pale yellow. But if the +Liquor be so much thicker as to stop also a great number of the +blue-making Rays, and some of the green-making, the rest must compound +an orange; and where it is so thick as to stop also a great number of +the green-making and a considerable number of the yellow-making, the +rest must begin to compound a red, and this red must grow deeper and +darker as the yellow-making and orange-making Rays are more and more +stopp'd by increasing the thickness of the Liquor, so that few Rays +besides the red-making can get through. + +Of this kind is an Experiment lately related to me by Mr. _Halley_, who, +in diving deep into the Sea in a diving Vessel, found in a clear +Sun-shine Day, that when he was sunk many Fathoms deep into the Water +the upper part of his Hand on which the Sun shone directly through the +Water and through a small Glass Window in the Vessel appeared of a red +Colour, like that of a Damask Rose, and the Water below and the under +part of his Hand illuminated by Light reflected from the Water below +look'd green. For thence it may be gather'd, that the Sea-Water reflects +back the violet and blue-making Rays most easily, and lets the +red-making Rays pass most freely and copiously to great Depths. For +thereby the Sun's direct Light at all great Depths, by reason of the +predominating red-making Rays, must appear red; and the greater the +Depth is, the fuller and intenser must that red be. And at such Depths +as the violet-making Rays scarce penetrate unto, the blue-making, +green-making, and yellow-making Rays being reflected from below more +copiously than the red-making ones, must compound a green. + +Now, if there be two Liquors of full Colours, suppose a red and blue, +and both of them so thick as suffices to make their Colours sufficiently +full; though either Liquor be sufficiently transparent apart, yet will +you not be able to see through both together. For, if only the +red-making Rays pass through one Liquor, and only the blue-making +through the other, no Rays can pass through both. This Mr. _Hook_ tried +casually with Glass Wedges filled with red and blue Liquors, and was +surprized at the unexpected Event, the reason of it being then unknown; +which makes me trust the more to his Experiment, though I have not tried +it my self. But he that would repeat it, must take care the Liquors be +of very good and full Colours. + +Now, whilst Bodies become coloured by reflecting or transmitting this or +that sort of Rays more copiously than the rest, it is to be conceived +that they stop and stifle in themselves the Rays which they do not +reflect or transmit. For, if Gold be foliated and held between your Eye +and the Light, the Light looks of a greenish blue, and therefore massy +Gold lets into its Body the blue-making Rays to be reflected to and fro +within it till they be stopp'd and stifled, whilst it reflects the +yellow-making outwards, and thereby looks yellow. And much after the +same manner that Leaf Gold is yellow by reflected, and blue by +transmitted Light, and massy Gold is yellow in all Positions of the Eye; +there are some Liquors, as the Tincture of _Lignum Nephriticum_, and +some sorts of Glass which transmit one sort of Light most copiously, and +reflect another sort, and thereby look of several Colours, according to +the Position of the Eye to the Light. But, if these Liquors or Glasses +were so thick and massy that no Light could get through them, I question +not but they would like all other opake Bodies appear of one and the +same Colour in all Positions of the Eye, though this I cannot yet affirm +by Experience. For all colour'd Bodies, so far as my Observation +reaches, may be seen through if made sufficiently thin, and therefore +are in some measure transparent, and differ only in degrees of +Transparency from tinged transparent Liquors; these Liquors, as well as +those Bodies, by a sufficient Thickness becoming opake. A transparent +Body which looks of any Colour by transmitted Light, may also look of +the same Colour by reflected Light, the Light of that Colour being +reflected by the farther Surface of the Body, or by the Air beyond it. +And then the reflected Colour will be diminished, and perhaps cease, by +making the Body very thick, and pitching it on the backside to diminish +the Reflexion of its farther Surface, so that the Light reflected from +the tinging Particles may predominate. In such Cases, the Colour of the +reflected Light will be apt to vary from that of the Light transmitted. +But whence it is that tinged Bodies and Liquors reflect some sort of +Rays, and intromit or transmit other sorts, shall be said in the next +Book. In this Proposition I content my self to have put it past dispute, +that Bodies have such Properties, and thence appear colour'd. + + +_PROP._ XI. PROB. VI. + +_By mixing colour'd Lights to compound a beam of Light of the same +Colour and Nature with a beam of the Sun's direct Light, and therein to +experience the Truth of the foregoing Propositions._ + +[Illustration: FIG. 16.] + +Let ABC _abc_ [in _Fig._ 16.] represent a Prism, by which the Sun's +Light let into a dark Chamber through the Hole F, may be refracted +towards the Lens MN, and paint upon it at _p_, _q_, _r_, _s_, and _t_, +the usual Colours violet, blue, green, yellow, and red, and let the +diverging Rays by the Refraction of this Lens converge again towards X, +and there, by the mixture of all those their Colours, compound a white +according to what was shewn above. Then let another Prism DEG _deg_, +parallel to the former, be placed at X, to refract that white Light +upwards towards Y. Let the refracting Angles of the Prisms, and their +distances from the Lens be equal, so that the Rays which converged from +the Lens towards X, and without Refraction, would there have crossed and +diverged again, may by the Refraction of the second Prism be reduced +into Parallelism and diverge no more. For then those Rays will recompose +a beam of white Light XY. If the refracting Angle of either Prism be the +bigger, that Prism must be so much the nearer to the Lens. You will know +when the Prisms and the Lens are well set together, by observing if the +beam of Light XY, which comes out of the second Prism be perfectly white +to the very edges of the Light, and at all distances from the Prism +continue perfectly and totally white like a beam of the Sun's Light. For +till this happens, the Position of the Prisms and Lens to one another +must be corrected; and then if by the help of a long beam of Wood, as is +represented in the Figure, or by a Tube, or some other such Instrument, +made for that Purpose, they be made fast in that Situation, you may try +all the same Experiments in this compounded beam of Light XY, which have +been made in the Sun's direct Light. For this compounded beam of Light +has the same appearance, and is endow'd with all the same Properties +with a direct beam of the Sun's Light, so far as my Observation reaches. +And in trying Experiments in this beam you may by stopping any of the +Colours, _p_, _q_, _r_, _s_, and _t_, at the Lens, see how the Colours +produced in the Experiments are no other than those which the Rays had +at the Lens before they entered the Composition of this Beam: And by +consequence, that they arise not from any new Modifications of the Light +by Refractions and Reflexions, but from the various Separations and +Mixtures of the Rays originally endow'd with their colour-making +Qualities. + +So, for instance, having with a Lens 4-1/4 Inches broad, and two Prisms +on either hand 6-1/4 Feet distant from the Lens, made such a beam of +compounded Light; to examine the reason of the Colours made by Prisms, I +refracted this compounded beam of Light XY with another Prism HIK _kh_, +and thereby cast the usual Prismatick Colours PQRST upon the Paper LV +placed behind. And then by stopping any of the Colours _p_, _q_, _r_, +_s_, _t_, at the Lens, I found that the same Colour would vanish at the +Paper. So if the Purple _p_ was stopp'd at the Lens, the Purple P upon +the Paper would vanish, and the rest of the Colours would remain +unalter'd, unless perhaps the blue, so far as some purple latent in it +at the Lens might be separated from it by the following Refractions. And +so by intercepting the green upon the Lens, the green R upon the Paper +would vanish, and so of the rest; which plainly shews, that as the white +beam of Light XY was compounded of several Lights variously colour'd at +the Lens, so the Colours which afterwards emerge out of it by new +Refractions are no other than those of which its Whiteness was +compounded. The Refraction of the Prism HIK _kh_ generates the Colours +PQRST upon the Paper, not by changing the colorific Qualities of the +Rays, but by separating the Rays which had the very same colorific +Qualities before they enter'd the Composition of the refracted beam of +white Light XY. For otherwise the Rays which were of one Colour at the +Lens might be of another upon the Paper, contrary to what we find. + +So again, to examine the reason of the Colours of natural Bodies, I +placed such Bodies in the Beam of Light XY, and found that they all +appeared there of those their own Colours which they have in Day-light, +and that those Colours depend upon the Rays which had the same Colours +at the Lens before they enter'd the Composition of that beam. Thus, for +instance, Cinnaber illuminated by this beam appears of the same red +Colour as in Day-light; and if at the Lens you intercept the +green-making and blue-making Rays, its redness will become more full and +lively: But if you there intercept the red-making Rays, it will not any +longer appear red, but become yellow or green, or of some other Colour, +according to the sorts of Rays which you do not intercept. So Gold in +this Light XY appears of the same yellow Colour as in Day-light, but by +intercepting at the Lens a due Quantity of the yellow-making Rays it +will appear white like Silver (as I have tried) which shews that its +yellowness arises from the Excess of the intercepted Rays tinging that +Whiteness with their Colour when they are let pass. So the Infusion of +_Lignum Nephriticum_ (as I have also tried) when held in this beam of +Light XY, looks blue by the reflected Part of the Light, and red by the +transmitted Part of it, as when 'tis view'd in Day-light; but if you +intercept the blue at the Lens the Infusion will lose its reflected blue +Colour, whilst its transmitted red remains perfect, and by the loss of +some blue-making Rays, wherewith it was allay'd, becomes more intense +and full. And, on the contrary, if the red and orange-making Rays be +intercepted at the Lens, the Infusion will lose its transmitted red, +whilst its blue will remain and become more full and perfect. Which +shews, that the Infusion does not tinge the Rays with blue and red, but +only transmits those most copiously which were red-making before, and +reflects those most copiously which were blue-making before. And after +the same manner may the Reasons of other Phænomena be examined, by +trying them in this artificial beam of Light XY. + +FOOTNOTES: + +[I] See p. 59. + +[J] _See our_ Author's Lect. Optic. _Part_ II. _Sect._ II. _p._ 239. + +[K] _As is done in our_ Author's Lect. Optic. _Part_ I. _Sect._ III. +_and_ IV. _and Part_ II. _Sect._ II. + +[L] _See our_ Author's Lect. Optic. _Part_ II. _Sect._ II. _pag._ 269, +&c. + +[M] _This is demonstrated in our_ Author's Lect. Optic. _Part_ I. +_Sect._ IV. _Prop._ 35 _and_ 36. + + + + +THE + +SECOND BOOK + +OF + +OPTICKS + + + + +_PART I._ + +_Observations concerning the Reflexions, Refractions, and Colours of +thin transparent Bodies._ + + +It has been observed by others, that transparent Substances, as Glass, +Water, Air, &c. when made very thin by being blown into Bubbles, or +otherwise formed into Plates, do exhibit various Colours according to +their various thinness, altho' at a greater thickness they appear very +clear and colourless. In the former Book I forbore to treat of these +Colours, because they seemed of a more difficult Consideration, and were +not necessary for establishing the Properties of Light there discoursed +of. But because they may conduce to farther Discoveries for compleating +the Theory of Light, especially as to the constitution of the parts of +natural Bodies, on which their Colours or Transparency depend; I have +here set down an account of them. To render this Discourse short and +distinct, I have first described the principal of my Observations, and +then consider'd and made use of them. The Observations are these. + +_Obs._ 1. Compressing two Prisms hard together that their sides (which +by chance were a very little convex) might somewhere touch one another: +I found the place in which they touched to become absolutely +transparent, as if they had there been one continued piece of Glass. For +when the Light fell so obliquely on the Air, which in other places was +between them, as to be all reflected; it seemed in that place of contact +to be wholly transmitted, insomuch that when look'd upon, it appeared +like a black or dark spot, by reason that little or no sensible Light +was reflected from thence, as from other places; and when looked through +it seemed (as it were) a hole in that Air which was formed into a thin +Plate, by being compress'd between the Glasses. And through this hole +Objects that were beyond might be seen distinctly, which could not at +all be seen through other parts of the Glasses where the Air was +interjacent. Although the Glasses were a little convex, yet this +transparent spot was of a considerable breadth, which breadth seemed +principally to proceed from the yielding inwards of the parts of the +Glasses, by reason of their mutual pressure. For by pressing them very +hard together it would become much broader than otherwise. + +_Obs._ 2. When the Plate of Air, by turning the Prisms about their +common Axis, became so little inclined to the incident Rays, that some +of them began to be transmitted, there arose in it many slender Arcs of +Colours which at first were shaped almost like the Conchoid, as you see +them delineated in the first Figure. And by continuing the Motion of the +Prisms, these Arcs increased and bended more and more about the said +transparent spot, till they were compleated into Circles or Rings +incompassing it, and afterwards continually grew more and more +contracted. + +[Illustration: FIG. 1.] + +These Arcs at their first appearance were of a violet and blue Colour, +and between them were white Arcs of Circles, which presently by +continuing the Motion of the Prisms became a little tinged in their +inward Limbs with red and yellow, and to their outward Limbs the blue +was adjacent. So that the order of these Colours from the central dark +spot, was at that time white, blue, violet; black, red, orange, yellow, +white, blue, violet, &c. But the yellow and red were much fainter than +the blue and violet. + +The Motion of the Prisms about their Axis being continued, these Colours +contracted more and more, shrinking towards the whiteness on either +side of it, until they totally vanished into it. And then the Circles in +those parts appear'd black and white, without any other Colours +intermix'd. But by farther moving the Prisms about, the Colours again +emerged out of the whiteness, the violet and blue at its inward Limb, +and at its outward Limb the red and yellow. So that now their order from +the central Spot was white, yellow, red; black; violet, blue, white, +yellow, red, &c. contrary to what it was before. + +_Obs._ 3. When the Rings or some parts of them appeared only black and +white, they were very distinct and well defined, and the blackness +seemed as intense as that of the central Spot. Also in the Borders of +the Rings, where the Colours began to emerge out of the whiteness, they +were pretty distinct, which made them visible to a very great multitude. +I have sometimes number'd above thirty Successions (reckoning every +black and white Ring for one Succession) and seen more of them, which by +reason of their smalness I could not number. But in other Positions of +the Prisms, at which the Rings appeared of many Colours, I could not +distinguish above eight or nine of them, and the Exterior of those were +very confused and dilute. + +In these two Observations to see the Rings distinct, and without any +other Colour than Black and white, I found it necessary to hold my Eye +at a good distance from them. For by approaching nearer, although in the +same inclination of my Eye to the Plane of the Rings, there emerged a +bluish Colour out of the white, which by dilating it self more and more +into the black, render'd the Circles less distinct, and left the white a +little tinged with red and yellow. I found also by looking through a +slit or oblong hole, which was narrower than the pupil of my Eye, and +held close to it parallel to the Prisms, I could see the Circles much +distincter and visible to a far greater number than otherwise. + +_Obs._ 4. To observe more nicely the order of the Colours which arose +out of the white Circles as the Rays became less and less inclined to +the Plate of Air; I took two Object-glasses, the one a Plano-convex for +a fourteen Foot Telescope, and the other a large double Convex for one +of about fifty Foot; and upon this, laying the other with its plane side +downwards, I pressed them slowly together, to make the Colours +successively emerge in the middle of the Circles, and then slowly lifted +the upper Glass from the lower to make them successively vanish again in +the same place. The Colour, which by pressing the Glasses together, +emerged last in the middle of the other Colours, would upon its first +appearance look like a Circle of a Colour almost uniform from the +circumference to the center and by compressing the Glasses still more, +grow continually broader until a new Colour emerged in its center, and +thereby it became a Ring encompassing that new Colour. And by +compressing the Glasses still more, the diameter of this Ring would +increase, and the breadth of its Orbit or Perimeter decrease until +another new Colour emerged in the center of the last: And so on until a +third, a fourth, a fifth, and other following new Colours successively +emerged there, and became Rings encompassing the innermost Colour, the +last of which was the black Spot. And, on the contrary, by lifting up +the upper Glass from the lower, the diameter of the Rings would +decrease, and the breadth of their Orbit increase, until their Colours +reached successively to the center; and then they being of a +considerable breadth, I could more easily discern and distinguish their +Species than before. And by this means I observ'd their Succession and +Quantity to be as followeth. + +Next to the pellucid central Spot made by the contact of the Glasses +succeeded blue, white, yellow, and red. The blue was so little in +quantity, that I could not discern it in the Circles made by the Prisms, +nor could I well distinguish any violet in it, but the yellow and red +were pretty copious, and seemed about as much in extent as the white, +and four or five times more than the blue. The next Circuit in order of +Colours immediately encompassing these were violet, blue, green, yellow, +and red: and these were all of them copious and vivid, excepting the +green, which was very little in quantity, and seemed much more faint and +dilute than the other Colours. Of the other four, the violet was the +least in extent, and the blue less than the yellow or red. The third +Circuit or Order was purple, blue, green, yellow, and red; in which the +purple seemed more reddish than the violet in the former Circuit, and +the green was much more conspicuous, being as brisk and copious as any +of the other Colours, except the yellow, but the red began to be a +little faded, inclining very much to purple. After this succeeded the +fourth Circuit of green and red. The green was very copious and lively, +inclining on the one side to blue, and on the other side to yellow. But +in this fourth Circuit there was neither violet, blue, nor yellow, and +the red was very imperfect and dirty. Also the succeeding Colours became +more and more imperfect and dilute, till after three or four revolutions +they ended in perfect whiteness. Their form, when the Glasses were most +compress'd so as to make the black Spot appear in the center, is +delineated in the second Figure; where _a_, _b_, _c_, _d_, _e_: _f_, +_g_, _h_, _i_, _k_: _l_, _m_, _n_, _o_, _p_: _q_, _r_: _s_, _t_: _v_, +_x_: _y_, _z_, denote the Colours reckon'd in order from the center, +black, blue, white, yellow, red: violet, blue, green, yellow, red: +purple, blue, green, yellow, red: green, red: greenish blue, red: +greenish blue, pale red: greenish blue, reddish white. + +[Illustration: FIG. 2.] + +_Obs._ 5. To determine the interval of the Glasses, or thickness of the +interjacent Air, by which each Colour was produced, I measured the +Diameters of the first six Rings at the most lucid part of their Orbits, +and squaring them, I found their Squares to be in the arithmetical +Progression of the odd Numbers, 1, 3, 5, 7, 9, 11. And since one of +these Glasses was plane, and the other spherical, their Intervals at +those Rings must be in the same Progression. I measured also the +Diameters of the dark or faint Rings between the more lucid Colours, and +found their Squares to be in the arithmetical Progression of the even +Numbers, 2, 4, 6, 8, 10, 12. And it being very nice and difficult to +take these measures exactly; I repeated them divers times at divers +parts of the Glasses, that by their Agreement I might be confirmed in +them. And the same method I used in determining some others of the +following Observations. + +_Obs._ 6. The Diameter of the sixth Ring at the most lucid part of its +Orbit was 58/100 parts of an Inch, and the Diameter of the Sphere on +which the double convex Object-glass was ground was about 102 Feet, and +hence I gathered the thickness of the Air or Aereal Interval of the +Glasses at that Ring. But some time after, suspecting that in making +this Observation I had not determined the Diameter of the Sphere with +sufficient accurateness, and being uncertain whether the Plano-convex +Glass was truly plane, and not something concave or convex on that side +which I accounted plane; and whether I had not pressed the Glasses +together, as I often did, to make them touch; (For by pressing such +Glasses together their parts easily yield inwards, and the Rings thereby +become sensibly broader than they would be, did the Glasses keep their +Figures.) I repeated the Experiment, and found the Diameter of the sixth +lucid Ring about 55/100 parts of an Inch. I repeated the Experiment also +with such an Object-glass of another Telescope as I had at hand. This +was a double Convex ground on both sides to one and the same Sphere, and +its Focus was distant from it 83-2/5 Inches. And thence, if the Sines of +Incidence and Refraction of the bright yellow Light be assumed in +proportion as 11 to 17, the Diameter of the Sphere to which the Glass +was figured will by computation be found 182 Inches. This Glass I laid +upon a flat one, so that the black Spot appeared in the middle of the +Rings of Colours without any other Pressure than that of the weight of +the Glass. And now measuring the Diameter of the fifth dark Circle as +accurately as I could, I found it the fifth part of an Inch precisely. +This Measure was taken with the points of a pair of Compasses on the +upper Surface on the upper Glass, and my Eye was about eight or nine +Inches distance from the Glass, almost perpendicularly over it, and the +Glass was 1/6 of an Inch thick, and thence it is easy to collect that +the true Diameter of the Ring between the Glasses was greater than its +measur'd Diameter above the Glasses in the Proportion of 80 to 79, or +thereabouts, and by consequence equal to 16/79 parts of an Inch, and its +true Semi-diameter equal to 8/79 parts. Now as the Diameter of the +Sphere (182 Inches) is to the Semi-diameter of this fifth dark Ring +(8/79 parts of an Inch) so is this Semi-diameter to the thickness of the +Air at this fifth dark Ring; which is therefore 32/567931 or +100/1774784. Parts of an Inch; and the fifth Part thereof, _viz._ the +1/88739 Part of an Inch, is the Thickness of the Air at the first of +these dark Rings. + +The same Experiment I repeated with another double convex Object-glass +ground on both sides to one and the same Sphere. Its Focus was distant +from it 168-1/2 Inches, and therefore the Diameter of that Sphere was +184 Inches. This Glass being laid upon the same plain Glass, the +Diameter of the fifth of the dark Rings, when the black Spot in their +Center appear'd plainly without pressing the Glasses, was by the measure +of the Compasses upon the upper Glass 121/600 Parts of an Inch, and by +consequence between the Glasses it was 1222/6000: For the upper Glass +was 1/8 of an Inch thick, and my Eye was distant from it 8 Inches. And a +third proportional to half this from the Diameter of the Sphere is +5/88850 Parts of an Inch. This is therefore the Thickness of the Air at +this Ring, and a fifth Part thereof, _viz._ the 1/88850th Part of an +Inch is the Thickness thereof at the first of the Rings, as above. + +I tried the same Thing, by laying these Object-glasses upon flat Pieces +of a broken Looking-glass, and found the same Measures of the Rings: +Which makes me rely upon them till they can be determin'd more +accurately by Glasses ground to larger Spheres, though in such Glasses +greater care must be taken of a true Plane. + +These Dimensions were taken, when my Eye was placed almost +perpendicularly over the Glasses, being about an Inch, or an Inch and a +quarter, distant from the incident Rays, and eight Inches distant from +the Glass; so that the Rays were inclined to the Glass in an Angle of +about four Degrees. Whence by the following Observation you will +understand, that had the Rays been perpendicular to the Glasses, the +Thickness of the Air at these Rings would have been less in the +Proportion of the Radius to the Secant of four Degrees, that is, of +10000 to 10024. Let the Thicknesses found be therefore diminish'd in +this Proportion, and they will become 1/88952 and 1/89063, or (to use +the nearest round Number) the 1/89000th Part of an Inch. This is the +Thickness of the Air at the darkest Part of the first dark Ring made by +perpendicular Rays; and half this Thickness multiplied by the +Progression, 1, 3, 5, 7, 9, 11, &c. gives the Thicknesses of the Air at +the most luminous Parts of all the brightest Rings, _viz._ 1/178000, +3/178000, 5/178000, 7/178000, &c. their arithmetical Means 2/178000, +4/178000, 6/178000, &c. being its Thicknesses at the darkest Parts of +all the dark ones. + +_Obs._ 7. The Rings were least, when my Eye was placed perpendicularly +over the Glasses in the Axis of the Rings: And when I view'd them +obliquely they became bigger, continually swelling as I removed my Eye +farther from the Axis. And partly by measuring the Diameter of the same +Circle at several Obliquities of my Eye, partly by other Means, as also +by making use of the two Prisms for very great Obliquities, I found its +Diameter, and consequently the Thickness of the Air at its Perimeter in +all those Obliquities to be very nearly in the Proportions express'd in +this Table. + +-------------------+--------------------+----------+---------- +Angle of Incidence |Angle of Refraction |Diameter |Thickness + on | into | of the | of the + the Air. | the Air. | Ring. | Air. +-------------------+--------------------+----------+---------- + Deg. Min. | | | + | | | + 00 00 | 00 00 | 10 | 10 + | | | + 06 26 | 10 00 | 10-1/13 | 10-2/13 + | | | + 12 45 | 20 00 | 10-1/3 | 10-2/3 + | | | + 18 49 | 30 00 | 10-3/4 | 11-1/2 + | | | + 24 30 | 40 00 | 11-2/5 | 13 + | | | + 29 37 | 50 00 | 12-1/2 | 15-1/2 + | | | + 33 58 | 60 00 | 14 | 20 + | | | + 35 47 | 65 00 | 15-1/4 | 23-1/4 + | | | + 37 19 | 70 00 | 16-4/5 | 28-1/4 + | | | + 38 33 | 75 00 | 19-1/4 | 37 + | | | + 39 27 | 80 00 | 22-6/7 | 52-1/4 + | | | + 40 00 | 85 00 | 29 | 84-1/12 + | | | + 40 11 | 90 00 | 35 | 122-1/2 +-------------------+--------------------+----------+---------- + +In the two first Columns are express'd the Obliquities of the incident +and emergent Rays to the Plate of the Air, that is, their Angles of +Incidence and Refraction. In the third Column the Diameter of any +colour'd Ring at those Obliquities is expressed in Parts, of which ten +constitute that Diameter when the Rays are perpendicular. And in the +fourth Column the Thickness of the Air at the Circumference of that Ring +is expressed in Parts, of which also ten constitute its Thickness when +the Rays are perpendicular. + +And from these Measures I seem to gather this Rule: That the Thickness +of the Air is proportional to the Secant of an Angle, whose Sine is a +certain mean Proportional between the Sines of Incidence and Refraction. +And that mean Proportional, so far as by these Measures I can determine +it, is the first of an hundred and six arithmetical mean Proportionals +between those Sines counted from the bigger Sine, that is, from the Sine +of Refraction when the Refraction is made out of the Glass into the +Plate of Air, or from the Sine of Incidence when the Refraction is made +out of the Plate of Air into the Glass. + +_Obs._ 8. The dark Spot in the middle of the Rings increased also by the +Obliquation of the Eye, although almost insensibly. But, if instead of +the Object-glasses the Prisms were made use of, its Increase was more +manifest when viewed so obliquely that no Colours appear'd about it. It +was least when the Rays were incident most obliquely on the interjacent +Air, and as the obliquity decreased it increased more and more until the +colour'd Rings appear'd, and then decreased again, but not so much as it +increased before. And hence it is evident, that the Transparency was +not only at the absolute Contact of the Glasses, but also where they had +some little Interval. I have sometimes observed the Diameter of that +Spot to be between half and two fifth parts of the Diameter of the +exterior Circumference of the red in the first Circuit or Revolution of +Colours when view'd almost perpendicularly; whereas when view'd +obliquely it hath wholly vanish'd and become opake and white like the +other parts of the Glass; whence it may be collected that the Glasses +did then scarcely, or not at all, touch one another, and that their +Interval at the perimeter of that Spot when view'd perpendicularly was +about a fifth or sixth part of their Interval at the circumference of +the said red. + +_Obs._ 9. By looking through the two contiguous Object-glasses, I found +that the interjacent Air exhibited Rings of Colours, as well by +transmitting Light as by reflecting it. The central Spot was now white, +and from it the order of the Colours were yellowish red; black, violet, +blue, white, yellow, red; violet, blue, green, yellow, red, &c. But +these Colours were very faint and dilute, unless when the Light was +trajected very obliquely through the Glasses: For by that means they +became pretty vivid. Only the first yellowish red, like the blue in the +fourth Observation, was so little and faint as scarcely to be discern'd. +Comparing the colour'd Rings made by Reflexion, with these made by +transmission of the Light; I found that white was opposite to black, red +to blue, yellow to violet, and green to a Compound of red and violet. +That is, those parts of the Glass were black when looked through, which +when looked upon appeared white, and on the contrary. And so those which +in one case exhibited blue, did in the other case exhibit red. And the +like of the other Colours. The manner you have represented in the third +Figure, where AB, CD, are the Surfaces of the Glasses contiguous at E, +and the black Lines between them are their Distances in arithmetical +Progression, and the Colours written above are seen by reflected Light, +and those below by Light transmitted (p. 209). + +_Obs._ 10. Wetting the Object-glasses a little at their edges, the Water +crept in slowly between them, and the Circles thereby became less and +the Colours more faint: Insomuch that as the Water crept along, one half +of them at which it first arrived would appear broken off from the other +half, and contracted into a less Room. By measuring them I found the +Proportions of their Diameters to the Diameters of the like Circles made +by Air to be about seven to eight, and consequently the Intervals of the +Glasses at like Circles, caused by those two Mediums Water and Air, are +as about three to four. Perhaps it may be a general Rule, That if any +other Medium more or less dense than Water be compress'd between the +Glasses, their Intervals at the Rings caused thereby will be to their +Intervals caused by interjacent Air, as the Sines are which measure the +Refraction made out of that Medium into Air. + +_Obs._ 11. When the Water was between the Glasses, if I pressed the +upper Glass variously at its edges to make the Rings move nimbly from +one place to another, a little white Spot would immediately follow the +center of them, which upon creeping in of the ambient Water into that +place would presently vanish. Its appearance was such as interjacent Air +would have caused, and it exhibited the same Colours. But it was not +air, for where any Bubbles of Air were in the Water they would not +vanish. The Reflexion must have rather been caused by a subtiler Medium, +which could recede through the Glasses at the creeping in of the Water. + +_Obs._ 12. These Observations were made in the open Air. But farther to +examine the Effects of colour'd Light falling on the Glasses, I darken'd +the Room, and view'd them by Reflexion of the Colours of a Prism cast on +a Sheet of white Paper, my Eye being so placed that I could see the +colour'd Paper by Reflexion in the Glasses, as in a Looking-glass. And +by this means the Rings became distincter and visible to a far greater +number than in the open Air. I have sometimes seen more than twenty of +them, whereas in the open Air I could not discern above eight or nine. + +[Illustration: FIG. 3.] + +_Obs._ 13. Appointing an Assistant to move the Prism to and fro about +its Axis, that all the Colours might successively fall on that part of +the Paper which I saw by Reflexion from that part of the Glasses, where +the Circles appear'd, so that all the Colours might be successively +reflected from the Circles to my Eye, whilst I held it immovable, I +found the Circles which the red Light made to be manifestly bigger than +those which were made by the blue and violet. And it was very pleasant +to see them gradually swell or contract accordingly as the Colour of the +Light was changed. The Interval of the Glasses at any of the Rings when +they were made by the utmost red Light, was to their Interval at the +same Ring when made by the utmost violet, greater than as 3 to 2, and +less than as 13 to 8. By the most of my Observations it was as 14 to 9. +And this Proportion seem'd very nearly the same in all Obliquities of my +Eye; unless when two Prisms were made use of instead of the +Object-glasses. For then at a certain great obliquity of my Eye, the +Rings made by the several Colours seem'd equal, and at a greater +obliquity those made by the violet would be greater than the same Rings +made by the red: the Refraction of the Prism in this case causing the +most refrangible Rays to fall more obliquely on that plate of the Air +than the least refrangible ones. Thus the Experiment succeeded in the +colour'd Light, which was sufficiently strong and copious to make the +Rings sensible. And thence it may be gather'd, that if the most +refrangible and least refrangible Rays had been copious enough to make +the Rings sensible without the mixture of other Rays, the Proportion +which here was 14 to 9 would have been a little greater, suppose 14-1/4 +or 14-1/3 to 9. + +_Obs._ 14. Whilst the Prism was turn'd about its Axis with an uniform +Motion, to make all the several Colours fall successively upon the +Object-glasses, and thereby to make the Rings contract and dilate: The +Contraction or Dilatation of each Ring thus made by the variation of its +Colour was swiftest in the red, and slowest in the violet, and in the +intermediate Colours it had intermediate degrees of Celerity. Comparing +the quantity of Contraction and Dilatation made by all the degrees of +each Colour, I found that it was greatest in the red; less in the +yellow, still less in the blue, and least in the violet. And to make as +just an Estimation as I could of the Proportions of their Contractions +or Dilatations, I observ'd that the whole Contraction or Dilatation of +the Diameter of any Ring made by all the degrees of red, was to that of +the Diameter of the same Ring made by all the degrees of violet, as +about four to three, or five to four, and that when the Light was of the +middle Colour between yellow and green, the Diameter of the Ring was +very nearly an arithmetical Mean between the greatest Diameter of the +same Ring made by the outmost red, and the least Diameter thereof made +by the outmost violet: Contrary to what happens in the Colours of the +oblong Spectrum made by the Refraction of a Prism, where the red is most +contracted, the violet most expanded, and in the midst of all the +Colours is the Confine of green and blue. And hence I seem to collect +that the thicknesses of the Air between the Glasses there, where the +Ring is successively made by the limits of the five principal Colours +(red, yellow, green, blue, violet) in order (that is, by the extreme +red, by the limit of red and yellow in the middle of the orange, by the +limit of yellow and green, by the limit of green and blue, by the limit +of blue and violet in the middle of the indigo, and by the extreme +violet) are to one another very nearly as the sixth lengths of a Chord +which found the Notes in a sixth Major, _sol_, _la_, _mi_, _fa_, _sol_, +_la_. But it agrees something better with the Observation to say, that +the thicknesses of the Air between the Glasses there, where the Rings +are successively made by the limits of the seven Colours, red, orange, +yellow, green, blue, indigo, violet in order, are to one another as the +Cube Roots of the Squares of the eight lengths of a Chord, which found +the Notes in an eighth, _sol_, _la_, _fa_, _sol_, _la_, _mi_, _fa_, +_sol_; that is, as the Cube Roots of the Squares of the Numbers, 1, 8/9, +5/6, 3/4, 2/3, 3/5, 9/16, 1/2. + +_Obs._ 15. These Rings were not of various Colours like those made in +the open Air, but appeared all over of that prismatick Colour only with +which they were illuminated. And by projecting the prismatick Colours +immediately upon the Glasses, I found that the Light which fell on the +dark Spaces which were between the Colour'd Rings was transmitted +through the Glasses without any variation of Colour. For on a white +Paper placed behind, it would paint Rings of the same Colour with those +which were reflected, and of the bigness of their immediate Spaces. And +from thence the origin of these Rings is manifest; namely, that the Air +between the Glasses, according to its various thickness, is disposed in +some places to reflect, and in others to transmit the Light of any one +Colour (as you may see represented in the fourth Figure) and in the same +place to reflect that of one Colour where it transmits that of another. + +[Illustration: FIG. 4.] + +_Obs._ 16. The Squares of the Diameters of these Rings made by any +prismatick Colour were in arithmetical Progression, as in the fifth +Observation. And the Diameter of the sixth Circle, when made by the +citrine yellow, and viewed almost perpendicularly was about 58/100 parts +of an Inch, or a little less, agreeable to the sixth Observation. + +The precedent Observations were made with a rarer thin Medium, +terminated by a denser, such as was Air or Water compress'd between two +Glasses. In those that follow are set down the Appearances of a denser +Medium thin'd within a rarer, such as are Plates of Muscovy Glass, +Bubbles of Water, and some other thin Substances terminated on all sides +with air. + +_Obs._ 17. If a Bubble be blown with Water first made tenacious by +dissolving a little Soap in it, 'tis a common Observation, that after a +while it will appear tinged with a great variety of Colours. To defend +these Bubbles from being agitated by the external Air (whereby their +Colours are irregularly moved one among another, so that no accurate +Observation can be made of them,) as soon as I had blown any of them I +cover'd it with a clear Glass, and by that means its Colours emerged in +a very regular order, like so many concentrick Rings encompassing the +top of the Bubble. And as the Bubble grew thinner by the continual +subsiding of the Water, these Rings dilated slowly and overspread the +whole Bubble, descending in order to the bottom of it, where they +vanish'd successively. In the mean while, after all the Colours were +emerged at the top, there grew in the center of the Rings a small round +black Spot, like that in the first Observation, which continually +dilated it self till it became sometimes more than 1/2 or 3/4 of an Inch +in breadth before the Bubble broke. At first I thought there had been no +Light reflected from the Water in that place, but observing it more +curiously, I saw within it several smaller round Spots, which appeared +much blacker and darker than the rest, whereby I knew that there was +some Reflexion at the other places which were not so dark as those +Spots. And by farther Tryal I found that I could see the Images of some +things (as of a Candle or the Sun) very faintly reflected, not only from +the great black Spot, but also from the little darker Spots which were +within it. + +Besides the aforesaid colour'd Rings there would often appear small +Spots of Colours, ascending and descending up and down the sides of the +Bubble, by reason of some Inequalities in the subsiding of the Water. +And sometimes small black Spots generated at the sides would ascend up +to the larger black Spot at the top of the Bubble, and unite with it. + +_Obs._ 18. Because the Colours of these Bubbles were more extended and +lively than those of the Air thinn'd between two Glasses, and so more +easy to be distinguish'd, I shall here give you a farther description of +their order, as they were observ'd in viewing them by Reflexion of the +Skies when of a white Colour, whilst a black substance was placed +behind the Bubble. And they were these, red, blue; red, blue; red, blue; +red, green; red, yellow, green, blue, purple; red, yellow, green, blue, +violet; red, yellow, white, blue, black. + +The three first Successions of red and blue were very dilute and dirty, +especially the first, where the red seem'd in a manner to be white. +Among these there was scarce any other Colour sensible besides red and +blue, only the blues (and principally the second blue) inclined a little +to green. + +The fourth red was also dilute and dirty, but not so much as the former +three; after that succeeded little or no yellow, but a copious green, +which at first inclined a little to yellow, and then became a pretty +brisk and good willow green, and afterwards changed to a bluish Colour; +but there succeeded neither blue nor violet. + +The fifth red at first inclined very much to purple, and afterwards +became more bright and brisk, but yet not very pure. This was succeeded +with a very bright and intense yellow, which was but little in quantity, +and soon chang'd to green: But that green was copious and something more +pure, deep and lively, than the former green. After that follow'd an +excellent blue of a bright Sky-colour, and then a purple, which was less +in quantity than the blue, and much inclined to red. + +The sixth red was at first of a very fair and lively scarlet, and soon +after of a brighter Colour, being very pure and brisk, and the best of +all the reds. Then after a lively orange follow'd an intense bright and +copious yellow, which was also the best of all the yellows, and this +changed first to a greenish yellow, and then to a greenish blue; but the +green between the yellow and the blue, was very little and dilute, +seeming rather a greenish white than a green. The blue which succeeded +became very good, and of a very bright Sky-colour, but yet something +inferior to the former blue; and the violet was intense and deep with +little or no redness in it. And less in quantity than the blue. + +In the last red appeared a tincture of scarlet next to violet, which +soon changed to a brighter Colour, inclining to an orange; and the +yellow which follow'd was at first pretty good and lively, but +afterwards it grew more dilute until by degrees it ended in perfect +whiteness. And this whiteness, if the Water was very tenacious and +well-temper'd, would slowly spread and dilate it self over the greater +part of the Bubble; continually growing paler at the top, where at +length it would crack in many places, and those cracks, as they dilated, +would appear of a pretty good, but yet obscure and dark Sky-colour; the +white between the blue Spots diminishing, until it resembled the Threds +of an irregular Net-work, and soon after vanish'd, and left all the +upper part of the Bubble of the said dark blue Colour. And this Colour, +after the aforesaid manner, dilated it self downwards, until sometimes +it hath overspread the whole Bubble. In the mean while at the top, which +was of a darker blue than the bottom, and appear'd also full of many +round blue Spots, something darker than the rest, there would emerge +one or more very black Spots, and within those, other Spots of an +intenser blackness, which I mention'd in the former Observation; and +these continually dilated themselves until the Bubble broke. + +If the Water was not very tenacious, the black Spots would break forth +in the white, without any sensible intervention of the blue. And +sometimes they would break forth within the precedent yellow, or red, or +perhaps within the blue of the second order, before the intermediate +Colours had time to display themselves. + +By this description you may perceive how great an affinity these Colours +have with those of Air described in the fourth Observation, although set +down in a contrary order, by reason that they begin to appear when the +Bubble is thickest, and are most conveniently reckon'd from the lowest +and thickest part of the Bubble upwards. + +_Obs._ 19. Viewing in several oblique Positions of my Eye the Rings of +Colours emerging on the top of the Bubble, I found that they were +sensibly dilated by increasing the obliquity, but yet not so much by far +as those made by thinn'd Air in the seventh Observation. For there they +were dilated so much as, when view'd most obliquely, to arrive at a part +of the Plate more than twelve times thicker than that where they +appear'd when viewed perpendicularly; whereas in this case the thickness +of the Water, at which they arrived when viewed most obliquely, was to +that thickness which exhibited them by perpendicular Rays, something +less than as 8 to 5. By the best of my Observations it was between 15 +and 15-1/2 to 10; an increase about 24 times less than in the other +case. + +Sometimes the Bubble would become of an uniform thickness all over, +except at the top of it near the black Spot, as I knew, because it would +exhibit the same appearance of Colours in all Positions of the Eye. And +then the Colours which were seen at its apparent circumference by the +obliquest Rays, would be different from those that were seen in other +places, by Rays less oblique to it. And divers Spectators might see the +same part of it of differing Colours, by viewing it at very differing +Obliquities. Now observing how much the Colours at the same places of +the Bubble, or at divers places of equal thickness, were varied by the +several Obliquities of the Rays; by the assistance of the 4th, 14th, +16th and 18th Observations, as they are hereafter explain'd, I collect +the thickness of the Water requisite to exhibit any one and the same +Colour, at several Obliquities, to be very nearly in the Proportion +expressed in this Table. + +-----------------+------------------+---------------- + Incidence on | Refraction into | Thickness of + the Water. | the Water. | the Water. +-----------------+------------------+---------------- + Deg. Min. | Deg. Min. | + | | + 00 00 | 00 00 | 10 + | | + 15 00 | 11 11 | 10-1/4 + | | + 30 00 | 22 1 | 10-4/5 + | | + 45 00 | 32 2 | 11-4/5 + | | + 60 00 | 40 30 | 13 + | | + 75 00 | 46 25 | 14-1/2 + | | + 90 00 | 48 35 | 15-1/5 +-----------------+------------------+---------------- + +In the two first Columns are express'd the Obliquities of the Rays to +the Superficies of the Water, that is, their Angles of Incidence and +Refraction. Where I suppose, that the Sines which measure them are in +round Numbers, as 3 to 4, though probably the Dissolution of Soap in the +Water, may a little alter its refractive Virtue. In the third Column, +the Thickness of the Bubble, at which any one Colour is exhibited in +those several Obliquities, is express'd in Parts, of which ten +constitute its Thickness when the Rays are perpendicular. And the Rule +found by the seventh Observation agrees well with these Measures, if +duly apply'd; namely, that the Thickness of a Plate of Water requisite +to exhibit one and the same Colour at several Obliquities of the Eye, is +proportional to the Secant of an Angle, whose Sine is the first of an +hundred and six arithmetical mean Proportionals between the Sines of +Incidence and Refraction counted from the lesser Sine, that is, from the +Sine of Refraction when the Refraction is made out of Air into Water, +otherwise from the Sine of Incidence. + +I have sometimes observ'd, that the Colours which arise on polish'd +Steel by heating it, or on Bell-metal, and some other metalline +Substances, when melted and pour'd on the Ground, where they may cool in +the open Air, have, like the Colours of Water-bubbles, been a little +changed by viewing them at divers Obliquities, and particularly that a +deep blue, or violet, when view'd very obliquely, hath been changed to a +deep red. But the Changes of these Colours are not so great and +sensible as of those made by Water. For the Scoria, or vitrified Part of +the Metal, which most Metals when heated or melted do continually +protrude, and send out to their Surface, and which by covering the +Metals in form of a thin glassy Skin, causes these Colours, is much +denser than Water; and I find that the Change made by the Obliquation of +the Eye is least in Colours of the densest thin Substances. + +_Obs._ 20. As in the ninth Observation, so here, the Bubble, by +transmitted Light, appear'd of a contrary Colour to that, which it +exhibited by Reflexion. Thus when the Bubble being look'd on by the +Light of the Clouds reflected from it, seemed red at its apparent +Circumference, if the Clouds at the same time, or immediately after, +were view'd through it, the Colour at its Circumference would be blue. +And, on the contrary, when by reflected Light it appeared blue, it would +appear red by transmitted Light. + +_Obs._ 21. By wetting very thin Plates of _Muscovy_ Glass, whose +thinness made the like Colours appear, the Colours became more faint and +languid, especially by wetting the Plates on that side opposite to the +Eye: But I could not perceive any variation of their Species. So then +the thickness of a Plate requisite to produce any Colour, depends only +on the density of the Plate, and not on that of the ambient Medium. And +hence, by the 10th and 16th Observations, may be known the thickness +which Bubbles of Water, or Plates of _Muscovy_ Glass, or other +Substances, have at any Colour produced by them. + +_Obs._ 22. A thin transparent Body, which is denser than its ambient +Medium, exhibits more brisk and vivid Colours than that which is so much +rarer; as I have particularly observed in the Air and Glass. For blowing +Glass very thin at a Lamp Furnace, those Plates encompassed with Air did +exhibit Colours much more vivid than those of Air made thin between two +Glasses. + +_Obs._ 23. Comparing the quantity of Light reflected from the several +Rings, I found that it was most copious from the first or inmost, and in +the exterior Rings became gradually less and less. Also the whiteness of +the first Ring was stronger than that reflected from those parts of the +thin Medium or Plate which were without the Rings; as I could manifestly +perceive by viewing at a distance the Rings made by the two +Object-glasses; or by comparing two Bubbles of Water blown at distant +Times, in the first of which the Whiteness appear'd, which succeeded all +the Colours, and in the other, the Whiteness which preceded them all. + +_Obs._ 24. When the two Object-glasses were lay'd upon one another, so +as to make the Rings of the Colours appear, though with my naked Eye I +could not discern above eight or nine of those Rings, yet by viewing +them through a Prism I have seen a far greater Multitude, insomuch that +I could number more than forty, besides many others, that were so very +small and close together, that I could not keep my Eye steady on them +severally so as to number them, but by their Extent I have sometimes +estimated them to be more than an hundred. And I believe the Experiment +may be improved to the Discovery of far greater Numbers. For they seem +to be really unlimited, though visible only so far as they can be +separated by the Refraction of the Prism, as I shall hereafter explain. + +[Illustration: FIG. 5.] + +But it was but one side of these Rings, namely, that towards which the +Refraction was made, which by that Refraction was render'd distinct, and +the other side became more confused than when view'd by the naked Eye, +insomuch that there I could not discern above one or two, and sometimes +none of those Rings, of which I could discern eight or nine with my +naked Eye. And their Segments or Arcs, which on the other side appear'd +so numerous, for the most part exceeded not the third Part of a Circle. +If the Refraction was very great, or the Prism very distant from the +Object-glasses, the middle Part of those Arcs became also confused, so +as to disappear and constitute an even Whiteness, whilst on either side +their Ends, as also the whole Arcs farthest from the Center, became +distincter than before, appearing in the Form as you see them design'd +in the fifth Figure. + +The Arcs, where they seem'd distinctest, were only white and black +successively, without any other Colours intermix'd. But in other Places +there appeared Colours, whose Order was inverted by the refraction in +such manner, that if I first held the Prism very near the +Object-glasses, and then gradually removed it farther off towards my +Eye, the Colours of the 2d, 3d, 4th, and following Rings, shrunk towards +the white that emerged between them, until they wholly vanish'd into it +at the middle of the Arcs, and afterwards emerged again in a contrary +Order. But at the Ends of the Arcs they retain'd their Order unchanged. + +I have sometimes so lay'd one Object-glass upon the other, that to the +naked Eye they have all over seem'd uniformly white, without the least +Appearance of any of the colour'd Rings; and yet by viewing them through +a Prism, great Multitudes of those Rings have discover'd themselves. And +in like manner Plates of _Muscovy_ Glass, and Bubbles of Glass blown at +a Lamp-Furnace, which were not so thin as to exhibit any Colours to the +naked Eye, have through the Prism exhibited a great Variety of them +ranged irregularly up and down in the Form of Waves. And so Bubbles of +Water, before they began to exhibit their Colours to the naked Eye of a +Bystander, have appeared through a Prism, girded about with many +parallel and horizontal Rings; to produce which Effect, it was necessary +to hold the Prism parallel, or very nearly parallel to the Horizon, and +to dispose it so that the Rays might be refracted upwards. + + + + +THE + +SECOND BOOK + +OF + +OPTICKS + + +_PART II._ + +_Remarks upon the foregoing Observations._ + + +Having given my Observations of these Colours, before I make use of them +to unfold the Causes of the Colours of natural Bodies, it is convenient +that by the simplest of them, such as are the 2d, 3d, 4th, 9th, 12th, +18th, 20th, and 24th, I first explain the more compounded. And first to +shew how the Colours in the fourth and eighteenth Observations are +produced, let there be taken in any Right Line from the Point Y, [in +_Fig._ 6.] the Lengths YA, YB, YC, YD, YE, YF, YG, YH, in proportion to +one another, as the Cube-Roots of the Squares of the Numbers, 1/2, 9/16, +3/5, 2/3, 3/4, 5/6, 8/9, 1, whereby the Lengths of a Musical Chord to +sound all the Notes in an eighth are represented; that is, in the +Proportion of the Numbers 6300, 6814, 7114, 7631, 8255, 8855, 9243, +10000. And at the Points A, B, C, D, E, F, G, H, let Perpendiculars +A[Greek: a], B[Greek: b], &c. be erected, by whose Intervals the Extent +of the several Colours set underneath against them, is to be +represented. Then divide the Line _A[Greek: a]_ in such Proportion as +the Numbers 1, 2, 3, 5, 6, 7, 9, 10, 11, &c. set at the Points of +Division denote. And through those Divisions from Y draw Lines 1I, 2K, +3L, 5M, 6N, 7O, &c. + +Now, if A2 be supposed to represent the Thickness of any thin +transparent Body, at which the outmost Violet is most copiously +reflected in the first Ring, or Series of Colours, then by the 13th +Observation, HK will represent its Thickness, at which the utmost Red is +most copiously reflected in the same Series. Also by the 5th and 16th +Observations, A6 and HN will denote the Thicknesses at which those +extreme Colours are most copiously reflected in the second Series, and +A10 and HQ the Thicknesses at which they are most copiously reflected in +the third Series, and so on. And the Thickness at which any of the +intermediate Colours are reflected most copiously, will, according to +the 14th Observation, be defined by the distance of the Line AH from the +intermediate parts of the Lines 2K, 6N, 10Q, &c. against which the Names +of those Colours are written below. + +[Illustration: FIG. 6.] + +But farther, to define the Latitude of these Colours in each Ring or +Series, let A1 design the least thickness, and A3 the greatest +thickness, at which the extreme violet in the first Series is reflected, +and let HI, and HL, design the like limits for the extreme red, and let +the intermediate Colours be limited by the intermediate parts of the +Lines 1I, and 3L, against which the Names of those Colours are written, +and so on: But yet with this caution, that the Reflexions be supposed +strongest at the intermediate Spaces, 2K, 6N, 10Q, &c. and from thence +to decrease gradually towards these limits, 1I, 3L, 5M, 7O, &c. on +either side; where you must not conceive them to be precisely limited, +but to decay indefinitely. And whereas I have assign'd the same Latitude +to every Series, I did it, because although the Colours in the first +Series seem to be a little broader than the rest, by reason of a +stronger Reflexion there, yet that inequality is so insensible as +scarcely to be determin'd by Observation. + +Now according to this Description, conceiving that the Rays originally +of several Colours are by turns reflected at the Spaces 1I, L3, 5M, O7, +9PR11, &c. and transmitted at the Spaces AHI1, 3LM5, 7OP9, &c. it is +easy to know what Colour must in the open Air be exhibited at any +thickness of a transparent thin Body. For if a Ruler be applied parallel +to AH, at that distance from it by which the thickness of the Body is +represented, the alternate Spaces 1IL3, 5MO7, &c. which it crosseth will +denote the reflected original Colours, of which the Colour exhibited in +the open Air is compounded. Thus if the constitution of the green in the +third Series of Colours be desired, apply the Ruler as you see at +[Greek: prsph], and by its passing through some of the blue at [Greek: +p] and yellow at [Greek: s], as well as through the green at [Greek: r], +you may conclude that the green exhibited at that thickness of the Body +is principally constituted of original green, but not without a mixture +of some blue and yellow. + +By this means you may know how the Colours from the center of the Rings +outward ought to succeed in order as they were described in the 4th and +18th Observations. For if you move the Ruler gradually from AH through +all distances, having pass'd over the first Space which denotes little +or no Reflexion to be made by thinnest Substances, it will first arrive +at 1 the violet, and then very quickly at the blue and green, which +together with that violet compound blue, and then at the yellow and red, +by whose farther addition that blue is converted into whiteness, which +whiteness continues during the transit of the edge of the Ruler from I +to 3, and after that by the successive deficience of its component +Colours, turns first to compound yellow, and then to red, and last of +all the red ceaseth at L. Then begin the Colours of the second Series, +which succeed in order during the transit of the edge of the Ruler from +5 to O, and are more lively than before, because more expanded and +severed. And for the same reason instead of the former white there +intercedes between the blue and yellow a mixture of orange, yellow, +green, blue and indigo, all which together ought to exhibit a dilute and +imperfect green. So the Colours of the third Series all succeed in +order; first, the violet, which a little interferes with the red of the +second order, and is thereby inclined to a reddish purple; then the blue +and green, which are less mix'd with other Colours, and consequently +more lively than before, especially the green: Then follows the yellow, +some of which towards the green is distinct and good, but that part of +it towards the succeeding red, as also that red is mix'd with the violet +and blue of the fourth Series, whereby various degrees of red very much +inclining to purple are compounded. This violet and blue, which should +succeed this red, being mixed with, and hidden in it, there succeeds a +green. And this at first is much inclined to blue, but soon becomes a +good green, the only unmix'd and lively Colour in this fourth Series. +For as it verges towards the yellow, it begins to interfere with the +Colours of the fifth Series, by whose mixture the succeeding yellow and +red are very much diluted and made dirty, especially the yellow, which +being the weaker Colour is scarce able to shew it self. After this the +several Series interfere more and more, and their Colours become more +and more intermix'd, till after three or four more revolutions (in which +the red and blue predominate by turns) all sorts of Colours are in all +places pretty equally blended, and compound an even whiteness. + +And since by the 15th Observation the Rays endued with one Colour are +transmitted, where those of another Colour are reflected, the reason of +the Colours made by the transmitted Light in the 9th and 20th +Observations is from hence evident. + +If not only the Order and Species of these Colours, but also the precise +thickness of the Plate, or thin Body at which they are exhibited, be +desired in parts of an Inch, that may be also obtained by assistance of +the 6th or 16th Observations. For according to those Observations the +thickness of the thinned Air, which between two Glasses exhibited the +most luminous parts of the first six Rings were 1/178000, 3/178000, +5/178000, 7/178000, 9/178000, 11/178000 parts of an Inch. Suppose the +Light reflected most copiously at these thicknesses be the bright +citrine yellow, or confine of yellow and orange, and these thicknesses +will be F[Greek: l], F[Greek: m], F[Greek: u], F[Greek: x], F[Greek: o], +F[Greek: t]. And this being known, it is easy to determine what +thickness of Air is represented by G[Greek: ph], or by any other +distance of the Ruler from AH. + +But farther, since by the 10th Observation the thickness of Air was to +the thickness of Water, which between the same Glasses exhibited the +same Colour, as 4 to 3, and by the 21st Observation the Colours of thin +Bodies are not varied by varying the ambient Medium; the thickness of a +Bubble of Water, exhibiting any Colour, will be 3/4 of the thickness of +Air producing the same Colour. And so according to the same 10th and +21st Observations, the thickness of a Plate of Glass, whose Refraction +of the mean refrangible Ray, is measured by the proportion of the Sines +31 to 20, may be 20/31 of the thickness of Air producing the same +Colours; and the like of other Mediums. I do not affirm, that this +proportion of 20 to 31, holds in all the Rays; for the Sines of other +sorts of Rays have other Proportions. But the differences of those +Proportions are so little that I do not here consider them. On these +Grounds I have composed the following Table, wherein the thickness of +Air, Water, and Glass, at which each Colour is most intense and +specifick, is expressed in parts of an Inch divided into ten hundred +thousand equal parts. + +Now if this Table be compared with the 6th Scheme, you will there see +the constitution of each Colour, as to its Ingredients, or the original +Colours of which it is compounded, and thence be enabled to judge of its +Intenseness or Imperfection; which may suffice in explication of the 4th +and 18th Observations, unless it be farther desired to delineate the +manner how the Colours appear, when the two Object-glasses are laid upon +one another. To do which, let there be described a large Arc of a +Circle, and a streight Line which may touch that Arc, and parallel to +that Tangent several occult Lines, at such distances from it, as the +Numbers set against the several Colours in the Table denote. For the +Arc, and its Tangent, will represent the Superficies of the Glasses +terminating the interjacent Air; and the places where the occult Lines +cut the Arc will show at what distances from the center, or Point of +contact, each Colour is reflected. + +_The thickness of colour'd Plates and Particles of_ + _____________|_______________ + / \ + Air. Water. Glass. + |---------+----------+----------+ + {Very black | 1/2 | 3/8 | 10/31 | + {Black | 1 | 3/4 | 20/31 | + {Beginning of | | | | + { Black | 2 | 1-1/2 | 1-2/7 | +Their Colours of the {Blue | 2-2/5 | 1-4/5 | 1-11/22 | +first Order, {White | 5-1/4 | 3-7/8 | 3-2/5 | + {Yellow | 7-1/9 | 5-1/3 | 4-3/5 | + {Orange | 8 | 6 | 5-1/6 | + {Red | 9 | 6-3/4 | 5-4/5 | + |---------+----------+----------| + {Violet | 11-1/6 | 8-3/8 | 7-1/5 | + {Indigo | 12-5/6 | 9-5/8 | 8-2/11 | + {Blue | 14 | 10-1/2 | 9 | + {Green | 15-1/8 | 11-2/3 | 9-5/7 | +Of the second order, {Yellow | 16-2/7 | 12-1/5 | 10-2/5 | + {Orange | 17-2/9 | 13 | 11-1/9 | + {Bright red | 18-1/3 | 13-3/4 | 11-5/6 | + {Scarlet | 19-2/3 | 14-3/4 | 12-2/3 | + |---------+----------+----------| + {Purple | 21 | 15-3/4 | 13-11/20 | + {Indigo | 22-1/10 | 16-4/7 | 14-1/4 | + {Blue | 23-2/5 | 17-11/20 | 15-1/10 | +Of the third Order, {Green | 25-1/5 | 18-9/10 | 16-1/4 | + {Yellow | 27-1/7 | 20-1/3 | 17-1/2 | + {Red | 29 | 21-3/4 | 18-5/7 | + {Bluish red | 32 | 24 | 20-2/3 | + |---------+----------+----------| + {Bluish green | 34 | 25-1/2 | 22 | + {Green | 35-2/7 | 26-1/2 | 22-3/4 | +Of the fourth Order, {Yellowish green | 36 | 27 | 23-2/9 | + {Red | 40-1/3 | 30-1/4 | 26 | + |---------+----------+----------| + {Greenish blue | 46 | 34-1/2 | 29-2/3 | +Of the fifth Order, {Red | 52-1/2 | 39-3/8 | 34 | + |---------+----------+----------| + {Greenish blue | 58-3/4 | 44 | 38 | +Of the sixth Order, {Red | 65 | 48-3/4 | 42 | + |---------+----------+----------| +Of the seventh Order, {Greenish blue | 71 | 53-1/4 | 45-4/5 | + {Ruddy White | 77 | 57-3/4 | 49-2/3 | + |---------+----------+----------| + +There are also other Uses of this Table: For by its assistance the +thickness of the Bubble in the 19th Observation was determin'd by the +Colours which it exhibited. And so the bigness of the parts of natural +Bodies may be conjectured by their Colours, as shall be hereafter shewn. +Also, if two or more very thin Plates be laid one upon another, so as to +compose one Plate equalling them all in thickness, the resulting Colour +may be hereby determin'd. For instance, Mr. _Hook_ observed, as is +mentioned in his _Micrographia_, that a faint yellow Plate of _Muscovy_ +Glass laid upon a blue one, constituted a very deep purple. The yellow +of the first Order is a faint one, and the thickness of the Plate +exhibiting it, according to the Table is 4-3/5, to which add 9, the +thickness exhibiting blue of the second Order, and the Sum will be +13-3/5, which is the thickness exhibiting the purple of the third Order. + +To explain, in the next place, the circumstances of the 2d and 3d +Observations; that is, how the Rings of the Colours may (by turning the +Prisms about their common Axis the contrary way to that expressed in +those Observations) be converted into white and black Rings, and +afterwards into Rings of Colours again, the Colours of each Ring lying +now in an inverted order; it must be remember'd, that those Rings of +Colours are dilated by the obliquation of the Rays to the Air which +intercedes the Glasses, and that according to the Table in the 7th +Observation, their Dilatation or Increase of their Diameter is most +manifest and speedy when they are obliquest. Now the Rays of yellow +being more refracted by the first Superficies of the said Air than those +of red, are thereby made more oblique to the second Superficies, at +which they are reflected to produce the colour'd Rings, and consequently +the yellow Circle in each Ring will be more dilated than the red; and +the Excess of its Dilatation will be so much the greater, by how much +the greater is the obliquity of the Rays, until at last it become of +equal extent with the red of the same Ring. And for the same reason the +green, blue and violet, will be also so much dilated by the still +greater obliquity of their Rays, as to become all very nearly of equal +extent with the red, that is, equally distant from the center of the +Rings. And then all the Colours of the same Ring must be co-incident, +and by their mixture exhibit a white Ring. And these white Rings must +have black and dark Rings between them, because they do not spread and +interfere with one another, as before. And for that reason also they +must become distincter, and visible to far greater numbers. But yet the +violet being obliquest will be something more dilated, in proportion to +its extent, than the other Colours, and so very apt to appear at the +exterior Verges of the white. + +Afterwards, by a greater obliquity of the Rays, the violet and blue +become more sensibly dilated than the red and yellow, and so being +farther removed from the center of the Rings, the Colours must emerge +out of the white in an order contrary to that which they had before; the +violet and blue at the exterior Limbs of each Ring, and the red and +yellow at the interior. And the violet, by reason of the greatest +obliquity of its Rays, being in proportion most of all expanded, will +soonest appear at the exterior Limb of each white Ring, and become more +conspicuous than the rest. And the several Series of Colours belonging +to the several Rings, will, by their unfolding and spreading, begin +again to interfere, and thereby render the Rings less distinct, and not +visible to so great numbers. + +If instead of the Prisms the Object-glasses be made use of, the Rings +which they exhibit become not white and distinct by the obliquity of the +Eye, by reason that the Rays in their passage through that Air which +intercedes the Glasses are very nearly parallel to those Lines in which +they were first incident on the Glasses, and consequently the Rays +endued with several Colours are not inclined one more than another to +that Air, as it happens in the Prisms. + +There is yet another circumstance of these Experiments to be consider'd, +and that is why the black and white Rings which when view'd at a +distance appear distinct, should not only become confused by viewing +them near at hand, but also yield a violet Colour at both the edges of +every white Ring. And the reason is, that the Rays which enter the Eye +at several parts of the Pupil, have several Obliquities to the Glasses, +and those which are most oblique, if consider'd apart, would represent +the Rings bigger than those which are the least oblique. Whence the +breadth of the Perimeter of every white Ring is expanded outwards by the +obliquest Rays, and inwards by the least oblique. And this Expansion is +so much the greater by how much the greater is the difference of the +Obliquity; that is, by how much the Pupil is wider, or the Eye nearer to +the Glasses. And the breadth of the violet must be most expanded, +because the Rays apt to excite a Sensation of that Colour are most +oblique to a second or farther Superficies of the thinn'd Air at which +they are reflected, and have also the greatest variation of Obliquity, +which makes that Colour soonest emerge out of the edges of the white. +And as the breadth of every Ring is thus augmented, the dark Intervals +must be diminish'd, until the neighbouring Rings become continuous, and +are blended, the exterior first, and then those nearer the center; so +that they can no longer be distinguish'd apart, but seem to constitute +an even and uniform whiteness. + +Among all the Observations there is none accompanied with so odd +circumstances as the twenty-fourth. Of those the principal are, that in +thin Plates, which to the naked Eye seem of an even and uniform +transparent whiteness, without any terminations of Shadows, the +Refraction of a Prism should make Rings of Colours appear, whereas it +usually makes Objects appear colour'd only there where they are +terminated with Shadows, or have parts unequally luminous; and that it +should make those Rings exceedingly distinct and white, although it +usually renders Objects confused and coloured. The Cause of these things +you will understand by considering, that all the Rings of Colours are +really in the Plate, when view'd with the naked Eye, although by reason +of the great breadth of their Circumferences they so much interfere and +are blended together, that they seem to constitute an uniform whiteness. +But when the Rays pass through the Prism to the Eye, the Orbits of the +several Colours in every Ring are refracted, some more than others, +according to their degrees of Refrangibility: By which means the Colours +on one side of the Ring (that is in the circumference on one side of its +center), become more unfolded and dilated, and those on the other side +more complicated and contracted. And where by a due Refraction they are +so much contracted, that the several Rings become narrower than to +interfere with one another, they must appear distinct, and also white, +if the constituent Colours be so much contracted as to be wholly +co-incident. But on the other side, where the Orbit of every Ring is +made broader by the farther unfolding of its Colours, it must interfere +more with other Rings than before, and so become less distinct. + +[Illustration: FIG. 7.] + +To explain this a little farther, suppose the concentrick Circles AV, +and BX, [in _Fig._ 7.] represent the red and violet of any Order, which, +together with the intermediate Colours, constitute any one of these +Rings. Now these being view'd through a Prism, the violet Circle BX, +will, by a greater Refraction, be farther translated from its place than +the red AV, and so approach nearer to it on that side of the Circles, +towards which the Refractions are made. For instance, if the red be +translated to _av_, the violet may be translated to _bx_, so as to +approach nearer to it at _x_ than before; and if the red be farther +translated to av, the violet may be so much farther translated to bx as +to convene with it at x; and if the red be yet farther translated to +[Greek: aY], the violet may be still so much farther translated to +[Greek: bx] as to pass beyond it at [Greek: x], and convene with it at +_e_ and _f_. And this being understood not only of the red and violet, +but of all the other intermediate Colours, and also of every revolution +of those Colours, you will easily perceive how those of the same +revolution or order, by their nearness at _xv_ and [Greek: Yx], and +their coincidence at xv, _e_ and _f_, ought to constitute pretty +distinct Arcs of Circles, especially at xv, or at _e_ and _f_; and that +they will appear severally at _x_[Greek: u] and at xv exhibit whiteness +by their coincidence, and again appear severally at [Greek: Yx], but yet +in a contrary order to that which they had before, and still retain +beyond _e_ and _f_. But on the other side, at _ab_, ab, or [Greek: ab], +these Colours must become much more confused by being dilated and spread +so as to interfere with those of other Orders. And the same confusion +will happen at [Greek: Ux] between _e_ and _f_, if the Refraction be +very great, or the Prism very distant from the Object-glasses: In which +case no parts of the Rings will be seen, save only two little Arcs at +_e_ and _f_, whose distance from one another will be augmented by +removing the Prism still farther from the Object-glasses: And these +little Arcs must be distinctest and whitest at their middle, and at +their ends, where they begin to grow confused, they must be colour'd. +And the Colours at one end of every Arc must be in a contrary order to +those at the other end, by reason that they cross in the intermediate +white; namely, their ends, which verge towards [Greek: Ux], will be red +and yellow on that side next the center, and blue and violet on the +other side. But their other ends which verge from [Greek: Ux], will on +the contrary be blue and violet on that side towards the center, and on +the other side red and yellow. + +Now as all these things follow from the properties of Light by a +mathematical way of reasoning, so the truth of them may be manifested by +Experiments. For in a dark Room, by viewing these Rings through a Prism, +by reflexion of the several prismatick Colours, which an assistant +causes to move to and fro upon a Wall or Paper from whence they are +reflected, whilst the Spectator's Eye, the Prism, and the +Object-glasses, (as in the 13th Observation,) are placed steady; the +Position of the Circles made successively by the several Colours, will +be found such, in respect of one another, as I have described in the +Figures _abxv_, or abxv, or _[Greek: abxU]_. And by the same method the +truth of the Explications of other Observations may be examined. + +By what hath been said, the like Phænomena of Water and thin Plates of +Glass may be understood. But in small fragments of those Plates there is +this farther observable, that where they lie flat upon a Table, and are +turned about their centers whilst they are view'd through a Prism, they +will in some postures exhibit Waves of various Colours; and some of them +exhibit these Waves in one or two Positions only, but the most of them +do in all Positions exhibit them, and make them for the most part appear +almost all over the Plates. The reason is, that the Superficies of such +Plates are not even, but have many Cavities and Swellings, which, how +shallow soever, do a little vary the thickness of the Plate. For at the +several sides of those Cavities, for the Reasons newly described, there +ought to be produced Waves in several postures of the Prism. Now though +it be but some very small and narrower parts of the Glass, by which +these Waves for the most part are caused, yet they may seem to extend +themselves over the whole Glass, because from the narrowest of those +parts there are Colours of several Orders, that is, of several Rings, +confusedly reflected, which by Refraction of the Prism are unfolded, +separated, and, according to their degrees of Refraction, dispersed to +several places, so as to constitute so many several Waves, as there were +divers orders of Colours promiscuously reflected from that part of the +Glass. + +These are the principal Phænomena of thin Plates or Bubbles, whose +Explications depend on the properties of Light, which I have heretofore +deliver'd. And these you see do necessarily follow from them, and agree +with them, even to their very least circumstances; and not only so, but +do very much tend to their proof. Thus, by the 24th Observation it +appears, that the Rays of several Colours, made as well by thin Plates +or Bubbles, as by Refractions of a Prism, have several degrees of +Refrangibility; whereby those of each order, which at the reflexion from +the Plate or Bubble are intermix'd with those of other orders, are +separated from them by Refraction, and associated together so as to +become visible by themselves like Arcs of Circles. For if the Rays were +all alike refrangible, 'tis impossible that the whiteness, which to the +naked Sense appears uniform, should by Refraction have its parts +transposed and ranged into those black and white Arcs. + +It appears also that the unequal Refractions of difform Rays proceed not +from any contingent irregularities; such as are Veins, an uneven Polish, +or fortuitous Position of the Pores of Glass; unequal and casual Motions +in the Air or Æther, the spreading, breaking, or dividing the same Ray +into many diverging parts; or the like. For, admitting any such +irregularities, it would be impossible for Refractions to render those +Rings so very distinct, and well defined, as they do in the 24th +Observation. It is necessary therefore that every Ray have its proper +and constant degree of Refrangibility connate with it, according to +which its refraction is ever justly and regularly perform'd; and that +several Rays have several of those degrees. + +And what is said of their Refrangibility may be also understood of their +Reflexibility, that is, of their Dispositions to be reflected, some at a +greater, and others at a less thickness of thin Plates or Bubbles; +namely, that those Dispositions are also connate with the Rays, and +immutable; as may appear by the 13th, 14th, and 15th Observations, +compared with the fourth and eighteenth. + +By the Precedent Observations it appears also, that whiteness is a +dissimilar mixture of all Colours, and that Light is a mixture of Rays +endued with all those Colours. For, considering the multitude of the +Rings of Colours in the 3d, 12th, and 24th Observations, it is manifest, +that although in the 4th and 18th Observations there appear no more than +eight or nine of those Rings, yet there are really a far greater number, +which so much interfere and mingle with one another, as after those +eight or nine revolutions to dilute one another wholly, and constitute +an even and sensibly uniform whiteness. And consequently that whiteness +must be allow'd a mixture of all Colours, and the Light which conveys it +to the Eye must be a mixture of Rays endued with all those Colours. + +But farther; by the 24th Observation it appears, that there is a +constant relation between Colours and Refrangibility; the most +refrangible Rays being violet, the least refrangible red, and those of +intermediate Colours having proportionably intermediate degrees of +Refrangibility. And by the 13th, 14th, and 15th Observations, compared +with the 4th or 18th there appears to be the same constant relation +between Colour and Reflexibility; the violet being in like circumstances +reflected at least thicknesses of any thin Plate or Bubble, the red at +greatest thicknesses, and the intermediate Colours at intermediate +thicknesses. Whence it follows, that the colorifick Dispositions of +Rays are also connate with them, and immutable; and by consequence, that +all the Productions and Appearances of Colours in the World are derived, +not from any physical Change caused in Light by Refraction or Reflexion, +but only from the various Mixtures or Separations of Rays, by virtue of +their different Refrangibility or Reflexibility. And in this respect the +Science of Colours becomes a Speculation as truly mathematical as any +other part of Opticks. I mean, so far as they depend on the Nature of +Light, and are not produced or alter'd by the Power of Imagination, or +by striking or pressing the Eye. + + + + +THE + +SECOND BOOK + +OF + +OPTICKS + + +_PART III._ + +_Of the permanent Colours of natural Bodies, and the Analogy between +them and the Colours of thin transparent Plates._ + +I am now come to another part of this Design, which is to consider how +the Phænomena of thin transparent Plates stand related to those of all +other natural Bodies. Of these Bodies I have already told you that they +appear of divers Colours, accordingly as they are disposed to reflect +most copiously the Rays originally endued with those Colours. But their +Constitutions, whereby they reflect some Rays more copiously than +others, remain to be discover'd; and these I shall endeavour to manifest +in the following Propositions. + + +PROP. I. + +_Those Superficies of transparent Bodies reflect the greatest quantity +of Light, which have the greatest refracting Power; that is, which +intercede Mediums that differ most in their refractive Densities. And in +the Confines of equally refracting Mediums there is no Reflexion._ + +The Analogy between Reflexion and Refraction will appear by considering, +that when Light passeth obliquely out of one Medium into another which +refracts from the perpendicular, the greater is the difference of their +refractive Density, the less Obliquity of Incidence is requisite to +cause a total Reflexion. For as the Sines are which measure the +Refraction, so is the Sine of Incidence at which the total Reflexion +begins, to the Radius of the Circle; and consequently that Angle of +Incidence is least where there is the greatest difference of the Sines. +Thus in the passing of Light out of Water into Air, where the Refraction +is measured by the Ratio of the Sines 3 to 4, the total Reflexion begins +when the Angle of Incidence is about 48 Degrees 35 Minutes. In passing +out of Glass into Air, where the Refraction is measured by the Ratio of +the Sines 20 to 31, the total Reflexion begins when the Angle of +Incidence is 40 Degrees 10 Minutes; and so in passing out of Crystal, or +more strongly refracting Mediums into Air, there is still a less +obliquity requisite to cause a total reflexion. Superficies therefore +which refract most do soonest reflect all the Light which is incident on +them, and so must be allowed most strongly reflexive. + +But the truth of this Proposition will farther appear by observing, that +in the Superficies interceding two transparent Mediums, (such as are +Air, Water, Oil, common Glass, Crystal, metalline Glasses, Island +Glasses, white transparent Arsenick, Diamonds, &c.) the Reflexion is +stronger or weaker accordingly, as the Superficies hath a greater or +less refracting Power. For in the Confine of Air and Sal-gem 'tis +stronger than in the Confine of Air and Water, and still stronger in the +Confine of Air and common Glass or Crystal, and stronger in the Confine +of Air and a Diamond. If any of these, and such like transparent Solids, +be immerged in Water, its Reflexion becomes, much weaker than before; +and still weaker if they be immerged in the more strongly refracting +Liquors of well rectified Oil of Vitriol or Spirit of Turpentine. If +Water be distinguish'd into two parts by any imaginary Surface, the +Reflexion in the Confine of those two parts is none at all. In the +Confine of Water and Ice 'tis very little; in that of Water and Oil 'tis +something greater; in that of Water and Sal-gem still greater; and in +that of Water and Glass, or Crystal or other denser Substances still +greater, accordingly as those Mediums differ more or less in their +refracting Powers. Hence in the Confine of common Glass and Crystal, +there ought to be a weak Reflexion, and a stronger Reflexion in the +Confine of common and metalline Glass; though I have not yet tried +this. But in the Confine of two Glasses of equal density, there is not +any sensible Reflexion; as was shewn in the first Observation. And the +same may be understood of the Superficies interceding two Crystals, or +two Liquors, or any other Substances in which no Refraction is caused. +So then the reason why uniform pellucid Mediums (such as Water, Glass, +or Crystal,) have no sensible Reflexion but in their external +Superficies, where they are adjacent to other Mediums of a different +density, is because all their contiguous parts have one and the same +degree of density. + + +PROP. II. + +_The least parts of almost all natural Bodies are in some measure +transparent: And the Opacity of those Bodies ariseth from the multitude +of Reflexions caused in their internal Parts._ + +That this is so has been observed by others, and will easily be granted +by them that have been conversant with Microscopes. And it may be also +tried by applying any substance to a hole through which some Light is +immitted into a dark Room. For how opake soever that Substance may seem +in the open Air, it will by that means appear very manifestly +transparent, if it be of a sufficient thinness. Only white metalline +Bodies must be excepted, which by reason of their excessive density seem +to reflect almost all the Light incident on their first Superficies; +unless by solution in Menstruums they be reduced into very small +Particles, and then they become transparent. + + +PROP. III. + +_Between the parts of opake and colour'd Bodies are many Spaces, either +empty, or replenish'd with Mediums of other Densities; as Water between +the tinging Corpuscles wherewith any Liquor is impregnated, Air between +the aqueous Globules that constitute Clouds or Mists; and for the most +part Spaces void of both Air and Water, but yet perhaps not wholly void +of all Substance, between the parts of hard Bodies._ + +The truth of this is evinced by the two precedent Propositions: For by +the second Proposition there are many Reflexions made by the internal +parts of Bodies, which, by the first Proposition, would not happen if +the parts of those Bodies were continued without any such Interstices +between them; because Reflexions are caused only in Superficies, which +intercede Mediums of a differing density, by _Prop._ 1. + +But farther, that this discontinuity of parts is the principal Cause of +the opacity of Bodies, will appear by considering, that opake Substances +become transparent by filling their Pores with any Substance of equal or +almost equal density with their parts. Thus Paper dipped in Water or +Oil, the _Oculus Mundi_ Stone steep'd in Water, Linnen Cloth oiled or +varnish'd, and many other Substances soaked in such Liquors as will +intimately pervade their little Pores, become by that means more +transparent than otherwise; so, on the contrary, the most transparent +Substances, may, by evacuating their Pores, or separating their parts, +be render'd sufficiently opake; as Salts or wet Paper, or the _Oculus +Mundi_ Stone by being dried, Horn by being scraped, Glass by being +reduced to Powder, or otherwise flawed; Turpentine by being stirred +about with Water till they mix imperfectly, and Water by being form'd +into many small Bubbles, either alone in the form of Froth, or by +shaking it together with Oil of Turpentine, or Oil Olive, or with some +other convenient Liquor, with which it will not perfectly incorporate. +And to the increase of the opacity of these Bodies, it conduces +something, that by the 23d Observation the Reflexions of very thin +transparent Substances are considerably stronger than those made by the +same Substances of a greater thickness. + + +PROP. IV. + +_The Parts of Bodies and their Interstices must not be less than of some +definite bigness, to render them opake and colour'd._ + +For the opakest Bodies, if their parts be subtilly divided, (as Metals, +by being dissolved in acid Menstruums, &c.) become perfectly +transparent. And you may also remember, that in the eighth Observation +there was no sensible reflexion at the Superficies of the +Object-glasses, where they were very near one another, though they did +not absolutely touch. And in the 17th Observation the Reflexion of the +Water-bubble where it became thinnest was almost insensible, so as to +cause very black Spots to appear on the top of the Bubble, by the want +of reflected Light. + +On these grounds I perceive it is that Water, Salt, Glass, Stones, and +such like Substances, are transparent. For, upon divers Considerations, +they seem to be as full of Pores or Interstices between their parts as +other Bodies are, but yet their Parts and Interstices to be too small to +cause Reflexions in their common Surfaces. + + +PROP. V. + +_The transparent parts of Bodies, according to their several sizes, +reflect Rays of one Colour, and transmit those of another, on the same +grounds that thin Plates or Bubbles do reflect or transmit those Rays. +And this I take to be the ground of all their Colours._ + +For if a thinn'd or plated Body, which being of an even thickness, +appears all over of one uniform Colour, should be slit into Threads, or +broken into Fragments, of the same thickness with the Plate; I see no +reason why every Thread or Fragment should not keep its Colour, and by +consequence why a heap of those Threads or Fragments should not +constitute a Mass or Powder of the same Colour, which the Plate +exhibited before it was broken. And the parts of all natural Bodies +being like so many Fragments of a Plate, must on the same grounds +exhibit the same Colours. + +Now, that they do so will appear by the affinity of their Properties. +The finely colour'd Feathers of some Birds, and particularly those of +Peacocks Tails, do, in the very same part of the Feather, appear of +several Colours in several Positions of the Eye, after the very same +manner that thin Plates were found to do in the 7th and 19th +Observations, and therefore their Colours arise from the thinness of the +transparent parts of the Feathers; that is, from the slenderness of the +very fine Hairs, or _Capillamenta_, which grow out of the sides of the +grosser lateral Branches or Fibres of those Feathers. And to the same +purpose it is, that the Webs of some Spiders, by being spun very fine, +have appeared colour'd, as some have observ'd, and that the colour'd +Fibres of some Silks, by varying the Position of the Eye, do vary their +Colour. Also the Colours of Silks, Cloths, and other Substances, which +Water or Oil can intimately penetrate, become more faint and obscure by +being immerged in those Liquors, and recover their Vigor again by being +dried; much after the manner declared of thin Bodies in the 10th and +21st Observations. Leaf-Gold, some sorts of painted Glass, the Infusion +of _Lignum Nephriticum_, and some other Substances, reflect one Colour, +and transmit another; like thin Bodies in the 9th and 20th Observations. +And some of those colour'd Powders which Painters use, may have their +Colours a little changed, by being very elaborately and finely ground. +Where I see not what can be justly pretended for those changes, besides +the breaking of their parts into less parts by that contrition, after +the same manner that the Colour of a thin Plate is changed by varying +its thickness. For which reason also it is that the colour'd Flowers of +Plants and Vegetables, by being bruised, usually become more transparent +than before, or at least in some degree or other change their Colours. +Nor is it much less to my purpose, that, by mixing divers Liquors, very +odd and remarkable Productions and Changes of Colours may be effected, +of which no cause can be more obvious and rational than that the saline +Corpuscles of one Liquor do variously act upon or unite with the tinging +Corpuscles of another, so as to make them swell, or shrink, (whereby not +only their bulk but their density also may be changed,) or to divide +them into smaller Corpuscles, (whereby a colour'd Liquor may become +transparent,) or to make many of them associate into one cluster, +whereby two transparent Liquors may compose a colour'd one. For we see +how apt those saline Menstruums are to penetrate and dissolve Substances +to which they are applied, and some of them to precipitate what others +dissolve. In like manner, if we consider the various Phænomena of the +Atmosphere, we may observe, that when Vapours are first raised, they +hinder not the transparency of the Air, being divided into parts too +small to cause any Reflexion in their Superficies. But when in order to +compose drops of Rain they begin to coalesce and constitute Globules of +all intermediate sizes, those Globules, when they become of convenient +size to reflect some Colours and transmit others, may constitute Clouds +of various Colours according to their sizes. And I see not what can be +rationally conceived in so transparent a Substance as Water for the +production of these Colours, besides the various sizes of its fluid and +globular Parcels. + + +PROP. VI. + +_The parts of Bodies on which their Colours depend, are denser than the +Medium which pervades their Interstices._ + +This will appear by considering, that the Colour of a Body depends not +only on the Rays which are incident perpendicularly on its parts, but on +those also which are incident at all other Angles. And that according to +the 7th Observation, a very little variation of obliquity will change +the reflected Colour, where the thin Body or small Particles is rarer +than the ambient Medium, insomuch that such a small Particle will at +diversly oblique Incidences reflect all sorts of Colours, in so great a +variety that the Colour resulting from them all, confusedly reflected +from a heap of such Particles, must rather be a white or grey than any +other Colour, or at best it must be but a very imperfect and dirty +Colour. Whereas if the thin Body or small Particle be much denser than +the ambient Medium, the Colours, according to the 19th Observation, are +so little changed by the variation of obliquity, that the Rays which +are reflected least obliquely may predominate over the rest, so much as +to cause a heap of such Particles to appear very intensely of their +Colour. + +It conduces also something to the confirmation of this Proposition, +that, according to the 22d Observation, the Colours exhibited by the +denser thin Body within the rarer, are more brisk than those exhibited +by the rarer within the denser. + + +PROP. VII. + +_The bigness of the component parts of natural Bodies may be conjectured +by their Colours._ + +For since the parts of these Bodies, by _Prop._ 5. do most probably +exhibit the same Colours with a Plate of equal thickness, provided they +have the same refractive density; and since their parts seem for the +most part to have much the same density with Water or Glass, as by many +circumstances is obvious to collect; to determine the sizes of those +parts, you need only have recourse to the precedent Tables, in which the +thickness of Water or Glass exhibiting any Colour is expressed. Thus if +it be desired to know the diameter of a Corpuscle, which being of equal +density with Glass shall reflect green of the third Order; the Number +16-1/4 shews it to be (16-1/4)/10000 parts of an Inch. + +The greatest difficulty is here to know of what Order the Colour of any +Body is. And for this end we must have recourse to the 4th and 18th +Observations; from whence may be collected these particulars. + +_Scarlets_, and other _reds_, _oranges_, and _yellows_, if they be pure +and intense, are most probably of the second order. Those of the first +and third order also may be pretty good; only the yellow of the first +order is faint, and the orange and red of the third Order have a great +Mixture of violet and blue. + +There may be good _Greens_ of the fourth Order, but the purest are of +the third. And of this Order the green of all Vegetables seems to be, +partly by reason of the Intenseness of their Colours, and partly because +when they wither some of them turn to a greenish yellow, and others to a +more perfect yellow or orange, or perhaps to red, passing first through +all the aforesaid intermediate Colours. Which Changes seem to be +effected by the exhaling of the Moisture which may leave the tinging +Corpuscles more dense, and something augmented by the Accretion of the +oily and earthy Part of that Moisture. Now the green, without doubt, is +of the same Order with those Colours into which it changeth, because the +Changes are gradual, and those Colours, though usually not very full, +yet are often too full and lively to be of the fourth Order. + +_Blues_ and _Purples_ may be either of the second or third Order, but +the best are of the third. Thus the Colour of Violets seems to be of +that Order, because their Syrup by acid Liquors turns red, and by +urinous and alcalizate turns green. For since it is of the Nature of +Acids to dissolve or attenuate, and of Alcalies to precipitate or +incrassate, if the Purple Colour of the Syrup was of the second Order, +an acid Liquor by attenuating its tinging Corpuscles would change it to +a red of the first Order, and an Alcali by incrassating them would +change it to a green of the second Order; which red and green, +especially the green, seem too imperfect to be the Colours produced by +these Changes. But if the said Purple be supposed of the third Order, +its Change to red of the second, and green of the third, may without any +Inconvenience be allow'd. + +If there be found any Body of a deeper and less reddish Purple than that +of the Violets, its Colour most probably is of the second Order. But yet +there being no Body commonly known whose Colour is constantly more deep +than theirs, I have made use of their Name to denote the deepest and +least reddish Purples, such as manifestly transcend their Colour in +purity. + +The _blue_ of the first Order, though very faint and little, may +possibly be the Colour of some Substances; and particularly the azure +Colour of the Skies seems to be of this Order. For all Vapours when they +begin to condense and coalesce into small Parcels, become first of that +Bigness, whereby such an Azure must be reflected before they can +constitute Clouds of other Colours. And so this being the first Colour +which Vapours begin to reflect, it ought to be the Colour of the finest +and most transparent Skies, in which Vapours are not arrived to that +Grossness requisite to reflect other Colours, as we find it is by +Experience. + +_Whiteness_, if most intense and luminous, is that of the first Order, +if less strong and luminous, a Mixture of the Colours of several Orders. +Of this last kind is the Whiteness of Froth, Paper, Linnen, and most +white Substances; of the former I reckon that of white Metals to be. For +whilst the densest of Metals, Gold, if foliated, is transparent, and all +Metals become transparent if dissolved in Menstruums or vitrified, the +Opacity of white Metals ariseth not from their Density alone. They being +less dense than Gold would be more transparent than it, did not some +other Cause concur with their Density to make them opake. And this Cause +I take to be such a Bigness of their Particles as fits them to reflect +the white of the first order. For, if they be of other Thicknesses they +may reflect other Colours, as is manifest by the Colours which appear +upon hot Steel in tempering it, and sometimes upon the Surface of melted +Metals in the Skin or Scoria which arises upon them in their cooling. +And as the white of the first order is the strongest which can be made +by Plates of transparent Substances, so it ought to be stronger in the +denser Substances of Metals than in the rarer of Air, Water, and Glass. +Nor do I see but that metallick Substances of such a Thickness as may +fit them to reflect the white of the first order, may, by reason of +their great Density (according to the Tenor of the first of these +Propositions) reflect all the Light incident upon them, and so be as +opake and splendent as it's possible for any Body to be. Gold, or Copper +mix'd with less than half their Weight of Silver, or Tin, or Regulus of +Antimony, in fusion, or amalgamed with a very little Mercury, become +white; which shews both that the Particles of white Metals have much +more Superficies, and so are smaller, than those of Gold and Copper, and +also that they are so opake as not to suffer the Particles of Gold or +Copper to shine through them. Now it is scarce to be doubted but that +the Colours of Gold and Copper are of the second and third order, and +therefore the Particles of white Metals cannot be much bigger than is +requisite to make them reflect the white of the first order. The +Volatility of Mercury argues that they are not much bigger, nor may they +be much less, lest they lose their Opacity, and become either +transparent as they do when attenuated by Vitrification, or by Solution +in Menstruums, or black as they do when ground smaller, by rubbing +Silver, or Tin, or Lead, upon other Substances to draw black Lines. The +first and only Colour which white Metals take by grinding their +Particles smaller, is black, and therefore their white ought to be that +which borders upon the black Spot in the Center of the Rings of Colours, +that is, the white of the first order. But, if you would hence gather +the Bigness of metallick Particles, you must allow for their Density. +For were Mercury transparent, its Density is such that the Sine of +Incidence upon it (by my Computation) would be to the Sine of its +Refraction, as 71 to 20, or 7 to 2. And therefore the Thickness of its +Particles, that they may exhibit the same Colours with those of Bubbles +of Water, ought to be less than the Thickness of the Skin of those +Bubbles in the Proportion of 2 to 7. Whence it's possible, that the +Particles of Mercury may be as little as the Particles of some +transparent and volatile Fluids, and yet reflect the white of the first +order. + +Lastly, for the production of _black_, the Corpuscles must be less than +any of those which exhibit Colours. For at all greater sizes there is +too much Light reflected to constitute this Colour. But if they be +supposed a little less than is requisite to reflect the white and very +faint blue of the first order, they will, according to the 4th, 8th, +17th and 18th Observations, reflect so very little Light as to appear +intensely black, and yet may perhaps variously refract it to and fro +within themselves so long, until it happen to be stifled and lost, by +which means they will appear black in all positions of the Eye without +any transparency. And from hence may be understood why Fire, and the +more subtile dissolver Putrefaction, by dividing the Particles of +Substances, turn them to black, why small quantities of black Substances +impart their Colour very freely and intensely to other Substances to +which they are applied; the minute Particles of these, by reason of +their very great number, easily overspreading the gross Particles of +others; why Glass ground very elaborately with Sand on a Copper Plate, +'till it be well polish'd, makes the Sand, together with what is worn +off from the Glass and Copper, become very black: why black Substances +do soonest of all others become hot in the Sun's Light and burn, (which +Effect may proceed partly from the multitude of Refractions in a little +room, and partly from the easy Commotion of so very small Corpuscles;) +and why blacks are usually a little inclined to a bluish Colour. For +that they are so may be seen by illuminating white Paper by Light +reflected from black Substances. For the Paper will usually appear of a +bluish white; and the reason is, that black borders in the obscure blue +of the order described in the 18th Observation, and therefore reflects +more Rays of that Colour than of any other. + +In these Descriptions I have been the more particular, because it is not +impossible but that Microscopes may at length be improved to the +discovery of the Particles of Bodies on which their Colours depend, if +they are not already in some measure arrived to that degree of +perfection. For if those Instruments are or can be so far improved as +with sufficient distinctness to represent Objects five or six hundred +times bigger than at a Foot distance they appear to our naked Eyes, I +should hope that we might be able to discover some of the greatest of +those Corpuscles. And by one that would magnify three or four thousand +times perhaps they might all be discover'd, but those which produce +blackness. In the mean while I see nothing material in this Discourse +that may rationally be doubted of, excepting this Position: That +transparent Corpuscles of the same thickness and density with a Plate, +do exhibit the same Colour. And this I would have understood not without +some Latitude, as well because those Corpuscles may be of irregular +Figures, and many Rays must be obliquely incident on them, and so have +a shorter way through them than the length of their Diameters, as +because the straitness of the Medium put in on all sides within such +Corpuscles may a little alter its Motions or other qualities on which +the Reflexion depends. But yet I cannot much suspect the last, because I +have observed of some small Plates of Muscovy Glass which were of an +even thickness, that through a Microscope they have appeared of the same +Colour at their edges and corners where the included Medium was +terminated, which they appeared of in other places. However it will add +much to our Satisfaction, if those Corpuscles can be discover'd with +Microscopes; which if we shall at length attain to, I fear it will be +the utmost improvement of this Sense. For it seems impossible to see the +more secret and noble Works of Nature within the Corpuscles by reason of +their transparency. + + +PROP. VIII. + +_The Cause of Reflexion is not the impinging of Light on the solid or +impervious parts of Bodies, as is commonly believed._ + +This will appear by the following Considerations. First, That in the +passage of Light out of Glass into Air there is a Reflexion as strong as +in its passage out of Air into Glass, or rather a little stronger, and +by many degrees stronger than in its passage out of Glass into Water. +And it seems not probable that Air should have more strongly reflecting +parts than Water or Glass. But if that should possibly be supposed, yet +it will avail nothing; for the Reflexion is as strong or stronger when +the Air is drawn away from the Glass, (suppose by the Air-Pump invented +by _Otto Gueriet_, and improved and made useful by Mr. _Boyle_) as when +it is adjacent to it. Secondly, If Light in its passage out of Glass +into Air be incident more obliquely than at an Angle of 40 or 41 Degrees +it is wholly reflected, if less obliquely it is in great measure +transmitted. Now it is not to be imagined that Light at one degree of +obliquity should meet with Pores enough in the Air to transmit the +greater part of it, and at another degree of obliquity should meet with +nothing but parts to reflect it wholly, especially considering that in +its passage out of Air into Glass, how oblique soever be its Incidence, +it finds Pores enough in the Glass to transmit a great part of it. If +any Man suppose that it is not reflected by the Air, but by the outmost +superficial parts of the Glass, there is still the same difficulty: +Besides, that such a Supposition is unintelligible, and will also appear +to be false by applying Water behind some part of the Glass instead of +Air. For so in a convenient obliquity of the Rays, suppose of 45 or 46 +Degrees, at which they are all reflected where the Air is adjacent to +the Glass, they shall be in great measure transmitted where the Water is +adjacent to it; which argues, that their Reflexion or Transmission +depends on the constitution of the Air and Water behind the Glass, and +not on the striking of the Rays upon the parts of the Glass. Thirdly, +If the Colours made by a Prism placed at the entrance of a Beam of Light +into a darken'd Room be successively cast on a second Prism placed at a +greater distance from the former, in such manner that they are all alike +incident upon it, the second Prism may be so inclined to the incident +Rays, that those which are of a blue Colour shall be all reflected by +it, and yet those of a red Colour pretty copiously transmitted. Now if +the Reflexion be caused by the parts of Air or Glass, I would ask, why +at the same Obliquity of Incidence the blue should wholly impinge on +those parts, so as to be all reflected, and yet the red find Pores +enough to be in a great measure transmitted. Fourthly, Where two Glasses +touch one another, there is no sensible Reflexion, as was declared in +the first Observation; and yet I see no reason why the Rays should not +impinge on the parts of Glass, as much when contiguous to other Glass as +when contiguous to Air. Fifthly, When the top of a Water-Bubble (in the +17th Observation,) by the continual subsiding and exhaling of the Water +grew very thin, there was such a little and almost insensible quantity +of Light reflected from it, that it appeared intensely black; whereas +round about that black Spot, where the Water was thicker, the Reflexion +was so strong as to make the Water seem very white. Nor is it only at +the least thickness of thin Plates or Bubbles, that there is no manifest +Reflexion, but at many other thicknesses continually greater and +greater. For in the 15th Observation the Rays of the same Colour were by +turns transmitted at one thickness, and reflected at another thickness, +for an indeterminate number of Successions. And yet in the Superficies +of the thinned Body, where it is of any one thickness, there are as many +parts for the Rays to impinge on, as where it is of any other thickness. +Sixthly, If Reflexion were caused by the parts of reflecting Bodies, it +would be impossible for thin Plates or Bubbles, at one and the same +place, to reflect the Rays of one Colour, and transmit those of another, +as they do according to the 13th and 15th Observations. For it is not to +be imagined that at one place the Rays which, for instance, exhibit a +blue Colour, should have the fortune to dash upon the parts, and those +which exhibit a red to hit upon the Pores of the Body; and then at +another place, where the Body is either a little thicker or a little +thinner, that on the contrary the blue should hit upon its pores, and +the red upon its parts. Lastly, Were the Rays of Light reflected by +impinging on the solid parts of Bodies, their Reflexions from polish'd +Bodies could not be so regular as they are. For in polishing Glass with +Sand, Putty, or Tripoly, it is not to be imagined that those Substances +can, by grating and fretting the Glass, bring all its least Particles to +an accurate Polish; so that all their Surfaces shall be truly plain or +truly spherical, and look all the same way, so as together to compose +one even Surface. The smaller the Particles of those Substances are, the +smaller will be the Scratches by which they continually fret and wear +away the Glass until it be polish'd; but be they never so small they can +wear away the Glass no otherwise than by grating and scratching it, and +breaking the Protuberances; and therefore polish it no otherwise than by +bringing its roughness to a very fine Grain, so that the Scratches and +Frettings of the Surface become too small to be visible. And therefore +if Light were reflected by impinging upon the solid parts of the Glass, +it would be scatter'd as much by the most polish'd Glass as by the +roughest. So then it remains a Problem, how Glass polish'd by fretting +Substances can reflect Light so regularly as it does. And this Problem +is scarce otherwise to be solved, than by saying, that the Reflexion of +a Ray is effected, not by a single point of the reflecting Body, but by +some power of the Body which is evenly diffused all over its Surface, +and by which it acts upon the Ray without immediate Contact. For that +the parts of Bodies do act upon Light at a distance shall be shewn +hereafter. + +Now if Light be reflected, not by impinging on the solid parts of +Bodies, but by some other principle; it's probable that as many of its +Rays as impinge on the solid parts of Bodies are not reflected but +stifled and lost in the Bodies. For otherwise we must allow two sorts of +Reflexions. Should all the Rays be reflected which impinge on the +internal parts of clear Water or Crystal, those Substances would rather +have a cloudy Colour than a clear Transparency. To make Bodies look +black, it's necessary that many Rays be stopp'd, retained, and lost in +them; and it seems not probable that any Rays can be stopp'd and +stifled in them which do not impinge on their parts. + +And hence we may understand that Bodies are much more rare and porous +than is commonly believed. Water is nineteen times lighter, and by +consequence nineteen times rarer than Gold; and Gold is so rare as very +readily and without the least opposition to transmit the magnetick +Effluvia, and easily to admit Quicksilver into its Pores, and to let +Water pass through it. For a concave Sphere of Gold filled with Water, +and solder'd up, has, upon pressing the Sphere with great force, let the +Water squeeze through it, and stand all over its outside in multitudes +of small Drops, like Dew, without bursting or cracking the Body of the +Gold, as I have been inform'd by an Eye witness. From all which we may +conclude, that Gold has more Pores than solid parts, and by consequence +that Water has above forty times more Pores than Parts. And he that +shall find out an Hypothesis, by which Water may be so rare, and yet not +be capable of compression by force, may doubtless by the same Hypothesis +make Gold, and Water, and all other Bodies, as much rarer as he pleases; +so that Light may find a ready passage through transparent Substances. + +The Magnet acts upon Iron through all dense Bodies not magnetick nor red +hot, without any diminution of its Virtue; as for instance, through +Gold, Silver, Lead, Glass, Water. The gravitating Power of the Sun is +transmitted through the vast Bodies of the Planets without any +diminution, so as to act upon all their parts to their very centers +with the same Force and according to the same Laws, as if the part upon +which it acts were not surrounded with the Body of the Planet, The Rays +of Light, whether they be very small Bodies projected, or only Motion or +Force propagated, are moved in right Lines; and whenever a Ray of Light +is by any Obstacle turned out of its rectilinear way, it will never +return into the same rectilinear way, unless perhaps by very great +accident. And yet Light is transmitted through pellucid solid Bodies in +right Lines to very great distances. How Bodies can have a sufficient +quantity of Pores for producing these Effects is very difficult to +conceive, but perhaps not altogether impossible. For the Colours of +Bodies arise from the Magnitudes of the Particles which reflect them, as +was explained above. Now if we conceive these Particles of Bodies to be +so disposed amongst themselves, that the Intervals or empty Spaces +between them may be equal in magnitude to them all; and that these +Particles may be composed of other Particles much smaller, which have as +much empty Space between them as equals all the Magnitudes of these +smaller Particles: And that in like manner these smaller Particles are +again composed of others much smaller, all which together are equal to +all the Pores or empty Spaces between them; and so on perpetually till +you come to solid Particles, such as have no Pores or empty Spaces +within them: And if in any gross Body there be, for instance, three such +degrees of Particles, the least of which are solid; this Body will have +seven times more Pores than solid Parts. But if there be four such +degrees of Particles, the least of which are solid, the Body will have +fifteen times more Pores than solid Parts. If there be five degrees, the +Body will have one and thirty times more Pores than solid Parts. If six +degrees, the Body will have sixty and three times more Pores than solid +Parts. And so on perpetually. And there are other ways of conceiving how +Bodies may be exceeding porous. But what is really their inward Frame is +not yet known to us. + + +PROP. IX. + +_Bodies reflect and refract Light by one and the same power, variously +exercised in various Circumstances._ + +This appears by several Considerations. First, Because when Light goes +out of Glass into Air, as obliquely as it can possibly do. If its +Incidence be made still more oblique, it becomes totally reflected. For +the power of the Glass after it has refracted the Light as obliquely as +is possible, if the Incidence be still made more oblique, becomes too +strong to let any of its Rays go through, and by consequence causes +total Reflexions. Secondly, Because Light is alternately reflected and +transmitted by thin Plates of Glass for many Successions, accordingly as +the thickness of the Plate increases in an arithmetical Progression. For +here the thickness of the Glass determines whether that Power by which +Glass acts upon Light shall cause it to be reflected, or suffer it to +be transmitted. And, Thirdly, because those Surfaces of transparent +Bodies which have the greatest refracting power, reflect the greatest +quantity of Light, as was shewn in the first Proposition. + + +PROP. X. + +_If Light be swifter in Bodies than in Vacuo, in the proportion of the +Sines which measure the Refraction of the Bodies, the Forces of the +Bodies to reflect and refract Light, are very nearly proportional to the +densities of the same Bodies; excepting that unctuous and sulphureous +Bodies refract more than others of this same density._ + +[Illustration: FIG. 8.] + +Let AB represent the refracting plane Surface of any Body, and IC a Ray +incident very obliquely upon the Body in C, so that the Angle ACI may be +infinitely little, and let CR be the refracted Ray. From a given Point B +perpendicular to the refracting Surface erect BR meeting with the +refracting Ray CR in R, and if CR represent the Motion of the refracted +Ray, and this Motion be distinguish'd into two Motions CB and BR, +whereof CB is parallel to the refracting Plane, and BR perpendicular to +it: CB shall represent the Motion of the incident Ray, and BR the +Motion generated by the Refraction, as Opticians have of late explain'd. + +Now if any Body or Thing, in moving through any Space of a given breadth +terminated on both sides by two parallel Planes, be urged forward in all +parts of that Space by Forces tending directly forwards towards the last +Plane, and before its Incidence on the first Plane, had no Motion +towards it, or but an infinitely little one; and if the Forces in all +parts of that Space, between the Planes, be at equal distances from the +Planes equal to one another, but at several distances be bigger or less +in any given Proportion, the Motion generated by the Forces in the whole +passage of the Body or thing through that Space shall be in a +subduplicate Proportion of the Forces, as Mathematicians will easily +understand. And therefore, if the Space of activity of the refracting +Superficies of the Body be consider'd as such a Space, the Motion of the +Ray generated by the refracting Force of the Body, during its passage +through that Space, that is, the Motion BR, must be in subduplicate +Proportion of that refracting Force. I say therefore, that the Square of +the Line BR, and by consequence the refracting Force of the Body, is +very nearly as the density of the same Body. For this will appear by the +following Table, wherein the Proportion of the Sines which measure the +Refractions of several Bodies, the Square of BR, supposing CB an unite, +the Densities of the Bodies estimated by their Specifick Gravities, and +their Refractive Power in respect of their Densities are set down in +several Columns. + +---------------------+----------------+----------------+----------+----------- + | | | | + | | The Square | The | The + | | of BR, to | density | refractive + | The Proportion | which the | and | Power of + | of the Sines of| refracting | specifick| the Body + | Incidence and | force of the | gravity | in respect + The refracting | Refraction of | Body is | of the | of its + Bodies. | yellow Light. | proportionate. | Body. | density. +---------------------+----------------+----------------+----------+----------- +A Pseudo-Topazius, | | | | + being a natural, | | | | + pellucid, brittle, | 23 to 14 | 1'699 | 4'27 | 3979 + hairy Stone, of a | | | | + yellow Colour. | | | | +Air. | 3201 to 3200 | 0'000625 | 0'0012 | 5208 +Glass of Antimony. | 17 to 9 | 2'568 | 5'28 | 4864 +A Selenitis. | 61 to 41 | 1'213 | 2'252 | 5386 +Glass vulgar. | 31 to 20 | 1'4025 | 2'58 | 5436 +Crystal of the Rock. | 25 to 16 | 1'445 | 2'65 | 5450 +Island Crystal. | 5 to 3 | 1'778 | 2'72 | 6536 +Sal Gemmæ. | 17 to 11 | 1'388 | 2'143 | 6477 +Alume. | 35 to 24 | 1'1267 | 1'714 | 6570 +Borax. | 22 to 15 | 1'1511 | 1'714 | 6716 +Niter. | 32 to 21 | 1'345 | 1'9 | 7079 +Dantzick Vitriol. | 303 to 200 | 1'295 | 1'715 | 7551 +Oil of Vitriol. | 10 to 7 | 1'041 | 1'7 | 6124 +Rain Water. | 529 to 396 | 0'7845 | 1' | 7845 +Gum Arabick. | 31 to 21 | 1'179 | 1'375 | 8574 +Spirit of Wine well | | | | + rectified. | 100 to 73 | 0'8765 | 0'866 | 10121 +Camphire. | 3 to 2 | 1'25 | 0'996 | 12551 +Oil Olive. | 22 to 15 | 1'1511 | 0'913 | 12607 +Linseed Oil. | 40 to 27 | 1'1948 | 0'932 | 12819 +Spirit of Turpentine.| 25 to 17 | 1'1626 | 0'874 | 13222 +Amber. | 14 to 9 | 1'42 | 1'04 | 13654 +A Diamond. | 100 to 41 | 4'949 | 3'4 | 14556 +---------------------+----------------+----------------+----------+----------- + +The Refraction of the Air in this Table is determin'd by that of the +Atmosphere observed by Astronomers. For, if Light pass through many +refracting Substances or Mediums gradually denser and denser, and +terminated with parallel Surfaces, the Sum of all the Refractions will +be equal to the single Refraction which it would have suffer'd in +passing immediately out of the first Medium into the last. And this +holds true, though the Number of the refracting Substances be increased +to Infinity, and the Distances from one another as much decreased, so +that the Light may be refracted in every Point of its Passage, and by +continual Refractions bent into a Curve-Line. And therefore the whole +Refraction of Light in passing through the Atmosphere from the highest +and rarest Part thereof down to the lowest and densest Part, must be +equal to the Refraction which it would suffer in passing at like +Obliquity out of a Vacuum immediately into Air of equal Density with +that in the lowest Part of the Atmosphere. + +Now, although a Pseudo-Topaz, a Selenitis, Rock Crystal, Island Crystal, +Vulgar Glass (that is, Sand melted together) and Glass of Antimony, +which are terrestrial stony alcalizate Concretes, and Air which probably +arises from such Substances by Fermentation, be Substances very +differing from one another in Density, yet by this Table, they have +their refractive Powers almost in the same Proportion to one another as +their Densities are, excepting that the Refraction of that strange +Substance, Island Crystal is a little bigger than the rest. And +particularly Air, which is 3500 Times rarer than the Pseudo-Topaz, and +4400 Times rarer than Glass of Antimony, and 2000 Times rarer than the +Selenitis, Glass vulgar, or Crystal of the Rock, has notwithstanding its +rarity the same refractive Power in respect of its Density which those +very dense Substances have in respect of theirs, excepting so far as +those differ from one another. + +Again, the Refraction of Camphire, Oil Olive, Linseed Oil, Spirit of +Turpentine and Amber, which are fat sulphureous unctuous Bodies, and a +Diamond, which probably is an unctuous Substance coagulated, have their +refractive Powers in Proportion to one another as their Densities +without any considerable Variation. But the refractive Powers of these +unctuous Substances are two or three Times greater in respect of their +Densities than the refractive Powers of the former Substances in respect +of theirs. + +Water has a refractive Power in a middle degree between those two sorts +of Substances, and probably is of a middle nature. For out of it grow +all vegetable and animal Substances, which consist as well of +sulphureous fat and inflamable Parts, as of earthy lean and alcalizate +ones. + +Salts and Vitriols have refractive Powers in a middle degree between +those of earthy Substances and Water, and accordingly are composed of +those two sorts of Substances. For by distillation and rectification of +their Spirits a great Part of them goes into Water, and a great Part +remains behind in the form of a dry fix'd Earth capable of +Vitrification. + +Spirit of Wine has a refractive Power in a middle degree between those +of Water and oily Substances, and accordingly seems to be composed of +both, united by Fermentation; the Water, by means of some saline Spirits +with which 'tis impregnated, dissolving the Oil, and volatizing it by +the Action. For Spirit of Wine is inflamable by means of its oily Parts, +and being distilled often from Salt of Tartar, grow by every +distillation more and more aqueous and phlegmatick. And Chymists +observe, that Vegetables (as Lavender, Rue, Marjoram, &c.) distilled +_per se_, before fermentation yield Oils without any burning Spirits, +but after fermentation yield ardent Spirits without Oils: Which shews, +that their Oil is by fermentation converted into Spirit. They find also, +that if Oils be poured in a small quantity upon fermentating Vegetables, +they distil over after fermentation in the form of Spirits. + +So then, by the foregoing Table, all Bodies seem to have their +refractive Powers proportional to their Densities, (or very nearly;) +excepting so far as they partake more or less of sulphureous oily +Particles, and thereby have their refractive Power made greater or less. +Whence it seems rational to attribute the refractive Power of all Bodies +chiefly, if not wholly, to the sulphureous Parts with which they abound. +For it's probable that all Bodies abound more or less with Sulphurs. And +as Light congregated by a Burning-glass acts most upon sulphureous +Bodies, to turn them into Fire and Flame; so, since all Action is +mutual, Sulphurs ought to act most upon Light. For that the action +between Light and Bodies is mutual, may appear from this Consideration; +That the densest Bodies which refract and reflect Light most strongly, +grow hottest in the Summer Sun, by the action of the refracted or +reflected Light. + +I have hitherto explain'd the power of Bodies to reflect and refract, +and shew'd, that thin transparent Plates, Fibres, and Particles, do, +according to their several thicknesses and densities, reflect several +sorts of Rays, and thereby appear of several Colours; and by consequence +that nothing more is requisite for producing all the Colours of natural +Bodies, than the several sizes and densities of their transparent +Particles. But whence it is that these Plates, Fibres, and Particles, +do, according to their several thicknesses and densities, reflect +several sorts of Rays, I have not yet explain'd. To give some insight +into this matter, and make way for understanding the next part of this +Book, I shall conclude this part with a few more Propositions. Those +which preceded respect the nature of Bodies, these the nature of Light: +For both must be understood, before the reason of their Actions upon one +another can be known. And because the last Proposition depended upon the +velocity of Light, I will begin with a Proposition of that kind. + + +PROP. XI. + +_Light is propagated from luminous Bodies in time, and spends about +seven or eight Minutes of an Hour in passing from the Sun to the Earth._ + +This was observed first by _Roemer_, and then by others, by means of the +Eclipses of the Satellites of _Jupiter_. For these Eclipses, when the +Earth is between the Sun and _Jupiter_, happen about seven or eight +Minutes sooner than they ought to do by the Tables, and when the Earth +is beyond the Sun they happen about seven or eight Minutes later than +they ought to do; the reason being, that the Light of the Satellites has +farther to go in the latter case than in the former by the Diameter of +the Earth's Orbit. Some inequalities of time may arise from the +Excentricities of the Orbs of the Satellites; but those cannot answer in +all the Satellites, and at all times to the Position and Distance of the +Earth from the Sun. The mean motions of _Jupiter_'s Satellites is also +swifter in his descent from his Aphelium to his Perihelium, than in his +ascent in the other half of his Orb. But this inequality has no respect +to the position of the Earth, and in the three interior Satellites is +insensible, as I find by computation from the Theory of their Gravity. + + +PROP. XII. + +_Every Ray of Light in its passage through any refracting Surface is put +into a certain transient Constitution or State, which in the progress of +the Ray returns at equal Intervals, and disposes the Ray at every return +to be easily transmitted through the next refracting Surface, and +between the returns to be easily reflected by it._ + +This is manifest by the 5th, 9th, 12th, and 15th Observations. For by +those Observations it appears, that one and the same sort of Rays at +equal Angles of Incidence on any thin transparent Plate, is alternately +reflected and transmitted for many Successions accordingly as the +thickness of the Plate increases in arithmetical Progression of the +Numbers, 0, 1, 2, 3, 4, 5, 6, 7, 8, &c. so that if the first Reflexion +(that which makes the first or innermost of the Rings of Colours there +described) be made at the thickness 1, the Rays shall be transmitted at +the thicknesses 0, 2, 4, 6, 8, 10, 12, &c. and thereby make the central +Spot and Rings of Light, which appear by transmission, and be reflected +at the thickness 1, 3, 5, 7, 9, 11, &c. and thereby make the Rings which +appear by Reflexion. And this alternate Reflexion and Transmission, as I +gather by the 24th Observation, continues for above an hundred +vicissitudes, and by the Observations in the next part of this Book, for +many thousands, being propagated from one Surface of a Glass Plate to +the other, though the thickness of the Plate be a quarter of an Inch or +above: So that this alternation seems to be propagated from every +refracting Surface to all distances without end or limitation. + +This alternate Reflexion and Refraction depends on both the Surfaces of +every thin Plate, because it depends on their distance. By the 21st +Observation, if either Surface of a thin Plate of _Muscovy_ Glass be +wetted, the Colours caused by the alternate Reflexion and Refraction +grow faint, and therefore it depends on them both. + +It is therefore perform'd at the second Surface; for if it were +perform'd at the first, before the Rays arrive at the second, it would +not depend on the second. + +It is also influenced by some action or disposition, propagated from the +first to the second, because otherwise at the second it would not depend +on the first. And this action or disposition, in its propagation, +intermits and returns by equal Intervals, because in all its progress it +inclines the Ray at one distance from the first Surface to be reflected +by the second, at another to be transmitted by it, and that by equal +Intervals for innumerable vicissitudes. And because the Ray is disposed +to Reflexion at the distances 1, 3, 5, 7, 9, &c. and to Transmission at +the distances 0, 2, 4, 6, 8, 10, &c. (for its transmission through the +first Surface, is at the distance 0, and it is transmitted through both +together, if their distance be infinitely little or much less than 1) +the disposition to be transmitted at the distances 2, 4, 6, 8, 10, &c. +is to be accounted a return of the same disposition which the Ray first +had at the distance 0, that is at its transmission through the first +refracting Surface. All which is the thing I would prove. + +What kind of action or disposition this is; Whether it consists in a +circulating or a vibrating motion of the Ray, or of the Medium, or +something else, I do not here enquire. Those that are averse from +assenting to any new Discoveries, but such as they can explain by an +Hypothesis, may for the present suppose, that as Stones by falling upon +Water put the Water into an undulating Motion, and all Bodies by +percussion excite vibrations in the Air; so the Rays of Light, by +impinging on any refracting or reflecting Surface, excite vibrations in +the refracting or reflecting Medium or Substance, and by exciting them +agitate the solid parts of the refracting or reflecting Body, and by +agitating them cause the Body to grow warm or hot; that the vibrations +thus excited are propagated in the refracting or reflecting Medium or +Substance, much after the manner that vibrations are propagated in the +Air for causing Sound, and move faster than the Rays so as to overtake +them; and that when any Ray is in that part of the vibration which +conspires with its Motion, it easily breaks through a refracting +Surface, but when it is in the contrary part of the vibration which +impedes its Motion, it is easily reflected; and, by consequence, that +every Ray is successively disposed to be easily reflected, or easily +transmitted, by every vibration which overtakes it. But whether this +Hypothesis be true or false I do not here consider. I content my self +with the bare Discovery, that the Rays of Light are by some cause or +other alternately disposed to be reflected or refracted for many +vicissitudes. + + +DEFINITION. + +_The returns of the disposition of any Ray to be reflected I will call +its_ Fits of easy Reflexion, _and those of its disposition to be +transmitted its_ Fits of easy Transmission, _and the space it passes +between every return and the next return, the_ Interval of its Fits. + + +PROP. XIII. + +_The reason why the Surfaces of all thick transparent Bodies reflect +part of the Light incident on them, and refract the rest, is, that some +Rays at their Incidence are in Fits of easy Reflexion, and others in +Fits of easy Transmission._ + +This may be gather'd from the 24th Observation, where the Light +reflected by thin Plates of Air and Glass, which to the naked Eye +appear'd evenly white all over the Plate, did through a Prism appear +waved with many Successions of Light and Darkness made by alternate Fits +of easy Reflexion and easy Transmission, the Prism severing and +distinguishing the Waves of which the white reflected Light was +composed, as was explain'd above. + +And hence Light is in Fits of easy Reflexion and easy Transmission, +before its Incidence on transparent Bodies. And probably it is put into +such fits at its first emission from luminous Bodies, and continues in +them during all its progress. For these Fits are of a lasting nature, as +will appear by the next part of this Book. + +In this Proposition I suppose the transparent Bodies to be thick; +because if the thickness of the Body be much less than the Interval of +the Fits of easy Reflexion and Transmission of the Rays, the Body loseth +its reflecting power. For if the Rays, which at their entering into the +Body are put into Fits of easy Transmission, arrive at the farthest +Surface of the Body before they be out of those Fits, they must be +transmitted. And this is the reason why Bubbles of Water lose their +reflecting power when they grow very thin; and why all opake Bodies, +when reduced into very small parts, become transparent. + + +PROP. XIV. + +_Those Surfaces of transparent Bodies, which if the Ray be in a Fit of +Refraction do refract it most strongly, if the Ray be in a Fit of +Reflexion do reflect it most easily._ + +For we shewed above, in _Prop._ 8. that the cause of Reflexion is not +the impinging of Light on the solid impervious parts of Bodies, but some +other power by which those solid parts act on Light at a distance. We +shewed also in _Prop._ 9. that Bodies reflect and refract Light by one +and the same power, variously exercised in various circumstances; and in +_Prop._ 1. that the most strongly refracting Surfaces reflect the most +Light: All which compared together evince and rarify both this and the +last Proposition. + + +PROP. XV. + +_In any one and the same sort of Rays, emerging in any Angle out of any +refracting Surface into one and the same Medium, the Interval of the +following Fits of easy Reflexion and Transmission are either accurately +or very nearly, as the Rectangle of the Secant of the Angle of +Refraction, and of the Secant of another Angle, whose Sine is the first +of 106 arithmetical mean Proportionals, between the Sines of Incidence +and Refraction, counted from the Sine of Refraction._ + +This is manifest by the 7th and 19th Observations. + + +PROP. XVI. + +_In several sorts of Rays emerging in equal Angles out of any refracting +Surface into the same Medium, the Intervals of the following Fits of +easy Reflexion and easy Transmission are either accurately, or very +nearly, as the Cube-Roots of the Squares of the lengths of a Chord, +which found the Notes in an Eight_, sol, la, fa, sol, la, mi, fa, sol, +_with all their intermediate degrees answering to the Colours of those +Rays, according to the Analogy described in the seventh Experiment of +the second Part of the first Book._ + +This is manifest by the 13th and 14th Observations. + + +PROP. XVII. + +_If Rays of any sort pass perpendicularly into several Mediums, the +Intervals of the Fits of easy Reflexion and Transmission in any one +Medium, are to those Intervals in any other, as the Sine of Incidence to +the Sine of Refraction, when the Rays pass out of the first of those two +Mediums into the second._ + +This is manifest by the 10th Observation. + + +PROP. XVIII. + +_If the Rays which paint the Colour in the Confine of yellow and orange +pass perpendicularly out of any Medium into Air, the Intervals of their +Fits of easy Reflexion are the 1/89000th part of an Inch. And of the +same length are the Intervals of their Fits of easy Transmission._ + +This is manifest by the 6th Observation. From these Propositions it is +easy to collect the Intervals of the Fits of easy Reflexion and easy +Transmission of any sort of Rays refracted in any angle into any Medium; +and thence to know, whether the Rays shall be reflected or transmitted +at their subsequent Incidence upon any other pellucid Medium. Which +thing, being useful for understanding the next part of this Book, was +here to be set down. And for the same reason I add the two following +Propositions. + + +PROP. XIX. + +_If any sort of Rays falling on the polite Surface of any pellucid +Medium be reflected back, the Fits of easy Reflexion, which they have at +the point of Reflexion, shall still continue to return; and the Returns +shall be at distances from the point of Reflexion in the arithmetical +progression of the Numbers 2, 4, 6, 8, 10, 12, &c. and between these +Fits the Rays shall be in Fits of easy Transmission._ + +For since the Fits of easy Reflexion and easy Transmission are of a +returning nature, there is no reason why these Fits, which continued +till the Ray arrived at the reflecting Medium, and there inclined the +Ray to Reflexion, should there cease. And if the Ray at the point of +Reflexion was in a Fit of easy Reflexion, the progression of the +distances of these Fits from that point must begin from 0, and so be of +the Numbers 0, 2, 4, 6, 8, &c. And therefore the progression of the +distances of the intermediate Fits of easy Transmission, reckon'd from +the same point, must be in the progression of the odd Numbers 1, 3, 5, +7, 9, &c. contrary to what happens when the Fits are propagated from +points of Refraction. + + +PROP. XX. + +_The Intervals of the Fits of easy Reflexion and easy Transmission, +propagated from points of Reflexion into any Medium, are equal to the +Intervals of the like Fits, which the same Rays would have, if refracted +into the same Medium in Angles of Refraction equal to their Angles of +Reflexion._ + +For when Light is reflected by the second Surface of thin Plates, it +goes out afterwards freely at the first Surface to make the Rings of +Colours which appear by Reflexion; and, by the freedom of its egress, +makes the Colours of these Rings more vivid and strong than those which +appear on the other side of the Plates by the transmitted Light. The +reflected Rays are therefore in Fits of easy Transmission at their +egress; which would not always happen, if the Intervals of the Fits +within the Plate after Reflexion were not equal, both in length and +number, to their Intervals before it. And this confirms also the +proportions set down in the former Proposition. For if the Rays both in +going in and out at the first Surface be in Fits of easy Transmission, +and the Intervals and Numbers of those Fits between the first and second +Surface, before and after Reflexion, be equal, the distances of the Fits +of easy Transmission from either Surface, must be in the same +progression after Reflexion as before; that is, from the first Surface +which transmitted them in the progression of the even Numbers 0, 2, 4, +6, 8, &c. and from the second which reflected them, in that of the odd +Numbers 1, 3, 5, 7, &c. But these two Propositions will become much more +evident by the Observations in the following part of this Book. + + + + +THE + +SECOND BOOK + +OF + +OPTICKS + + +_PART IV._ + +_Observations concerning the Reflexions and Colours of thick transparent +polish'd Plates._ + +There is no Glass or Speculum how well soever polished, but, besides the +Light which it refracts or reflects regularly, scatters every way +irregularly a faint Light, by means of which the polish'd Surface, when +illuminated in a dark room by a beam of the Sun's Light, may be easily +seen in all positions of the Eye. There are certain Phænomena of this +scatter'd Light, which when I first observed them, seem'd very strange +and surprizing to me. My Observations were as follows. + +_Obs._ 1. The Sun shining into my darken'd Chamber through a hole one +third of an Inch wide, I let the intromitted beam of Light fall +perpendicularly upon a Glass Speculum ground concave on one side and +convex on the other, to a Sphere of five Feet and eleven Inches Radius, +and Quick-silver'd over on the convex side. And holding a white opake +Chart, or a Quire of Paper at the center of the Spheres to which the +Speculum was ground, that is, at the distance of about five Feet and +eleven Inches from the Speculum, in such manner, that the beam of Light +might pass through a little hole made in the middle of the Chart to the +Speculum, and thence be reflected back to the same hole: I observed upon +the Chart four or five concentric Irises or Rings of Colours, like +Rain-bows, encompassing the hole much after the manner that those, which +in the fourth and following Observations of the first part of this Book +appear'd between the Object-glasses, encompassed the black Spot, but yet +larger and fainter than those. These Rings as they grew larger and +larger became diluter and fainter, so that the fifth was scarce visible. +Yet sometimes, when the Sun shone very clear, there appear'd faint +Lineaments of a sixth and seventh. If the distance of the Chart from the +Speculum was much greater or much less than that of six Feet, the Rings +became dilute and vanish'd. And if the distance of the Speculum from the +Window was much greater than that of six Feet, the reflected beam of +Light would be so broad at the distance of six Feet from the Speculum +where the Rings appear'd, as to obscure one or two of the innermost +Rings. And therefore I usually placed the Speculum at about six Feet +from the Window; so that its Focus might there fall in with the center +of its concavity at the Rings upon the Chart. And this Posture is always +to be understood in the following Observations where no other is +express'd. + +_Obs._ 2. The Colours of these Rain-bows succeeded one another from the +center outwards, in the same form and order with those which were made +in the ninth Observation of the first Part of this Book by Light not +reflected, but transmitted through the two Object-glasses. For, first, +there was in their common center a white round Spot of faint Light, +something broader than the reflected beam of Light, which beam sometimes +fell upon the middle of the Spot, and sometimes by a little inclination +of the Speculum receded from the middle, and left the Spot white to the +center. + +This white Spot was immediately encompassed with a dark grey or russet, +and that dark grey with the Colours of the first Iris; which Colours on +the inside next the dark grey were a little violet and indigo, and next +to that a blue, which on the outside grew pale, and then succeeded a +little greenish yellow, and after that a brighter yellow, and then on +the outward edge of the Iris a red which on the outside inclined to +purple. + +This Iris was immediately encompassed with a second, whose Colours were +in order from the inside outwards, purple, blue, green, yellow, light +red, a red mix'd with purple. + +Then immediately follow'd the Colours of the third Iris, which were in +order outwards a green inclining to purple, a good green, and a red more +bright than that of the former Iris. + +The fourth and fifth Iris seem'd of a bluish green within, and red +without, but so faintly that it was difficult to discern the Colours. + +_Obs._ 3. Measuring the Diameters of these Rings upon the Chart as +accurately as I could, I found them also in the same proportion to one +another with the Rings made by Light transmitted through the two +Object-glasses. For the Diameters of the four first of the bright Rings +measured between the brightest parts of their Orbits, at the distance of +six Feet from the Speculum were 1-11/16, 2-3/8, 2-11/12, 3-3/8 Inches, +whose Squares are in arithmetical progression of the numbers 1, 2, 3, 4. +If the white circular Spot in the middle be reckon'd amongst the Rings, +and its central Light, where it seems to be most luminous, be put +equipollent to an infinitely little Ring; the Squares of the Diameters +of the Rings will be in the progression 0, 1, 2, 3, 4, &c. I measured +also the Diameters of the dark Circles between these luminous ones, and +found their Squares in the progression of the numbers 1/2, 1-1/2, 2-1/2, +3-1/2, &c. the Diameters of the first four at the distance of six Feet +from the Speculum, being 1-3/16, 2-1/16, 2-2/3, 3-3/20 Inches. If the +distance of the Chart from the Speculum was increased or diminished, the +Diameters of the Circles were increased or diminished proportionally. + +_Obs._ 4. By the analogy between these Rings and those described in the +Observations of the first Part of this Book, I suspected that there +were many more of them which spread into one another, and by interfering +mix'd their Colours, and diluted one another so that they could not be +seen apart. I viewed them therefore through a Prism, as I did those in +the 24th Observation of the first Part of this Book. And when the Prism +was so placed as by refracting the Light of their mix'd Colours to +separate them, and distinguish the Rings from one another, as it did +those in that Observation, I could then see them distincter than before, +and easily number eight or nine of them, and sometimes twelve or +thirteen. And had not their Light been so very faint, I question not but +that I might have seen many more. + +_Obs._ 5. Placing a Prism at the Window to refract the intromitted beam +of Light, and cast the oblong Spectrum of Colours on the Speculum: I +covered the Speculum with a black Paper which had in the middle of it a +hole to let any one of the Colours pass through to the Speculum, whilst +the rest were intercepted by the Paper. And now I found Rings of that +Colour only which fell upon the Speculum. If the Speculum was +illuminated with red, the Rings were totally red with dark Intervals, if +with blue they were totally blue, and so of the other Colours. And when +they were illuminated with any one Colour, the Squares of their +Diameters measured between their most luminous Parts, were in the +arithmetical Progression of the Numbers, 0, 1, 2, 3, 4 and the Squares +of the Diameters of their dark Intervals in the Progression of the +intermediate Numbers 1/2, 1-1/2, 2-1/2, 3-1/2. But if the Colour was +varied, they varied their Magnitude. In the red they were largest, in +the indigo and violet least, and in the intermediate Colours yellow, +green, and blue, they were of several intermediate Bignesses answering +to the Colour, that is, greater in yellow than in green, and greater in +green than in blue. And hence I knew, that when the Speculum was +illuminated with white Light, the red and yellow on the outside of the +Rings were produced by the least refrangible Rays, and the blue and +violet by the most refrangible, and that the Colours of each Ring spread +into the Colours of the neighbouring Rings on either side, after the +manner explain'd in the first and second Part of this Book, and by +mixing diluted one another so that they could not be distinguish'd, +unless near the Center where they were least mix'd. For in this +Observation I could see the Rings more distinctly, and to a greater +Number than before, being able in the yellow Light to number eight or +nine of them, besides a faint shadow of a tenth. To satisfy my self how +much the Colours of the several Rings spread into one another, I +measured the Diameters of the second and third Rings, and found them +when made by the Confine of the red and orange to be to the same +Diameters when made by the Confine of blue and indigo, as 9 to 8, or +thereabouts. For it was hard to determine this Proportion accurately. +Also the Circles made successively by the red, yellow, and green, +differ'd more from one another than those made successively by the +green, blue, and indigo. For the Circle made by the violet was too dark +to be seen. To carry on the Computation, let us therefore suppose that +the Differences of the Diameters of the Circles made by the outmost red, +the Confine of red and orange, the Confine of orange and yellow, the +Confine of yellow and green, the Confine of green and blue, the Confine +of blue and indigo, the Confine of indigo and violet, and outmost +violet, are in proportion as the Differences of the Lengths of a +Monochord which sound the Tones in an Eight; _sol_, _la_, _fa_, _sol_, +_la_, _mi_, _fa_, _sol_, that is, as the Numbers 1/9, 1/18, 1/12, 1/12, +2/27, 1/27, 1/18. And if the Diameter of the Circle made by the Confine +of red and orange be 9A, and that of the Circle made by the Confine of +blue and indigo be 8A as above; their difference 9A-8A will be to the +difference of the Diameters of the Circles made by the outmost red, and +by the Confine of red and orange, as 1/18 + 1/12 + 1/12 + 2/27 to 1/9, +that is as 8/27 to 1/9, or 8 to 3, and to the difference of the Circles +made by the outmost violet, and by the Confine of blue and indigo, as +1/18 + 1/12 + 1/12 + 2/27 to 1/27 + 1/18, that is, as 8/27 to 5/54, or +as 16 to 5. And therefore these differences will be 3/8A and 5/16A. Add +the first to 9A and subduct the last from 8A, and you will have the +Diameters of the Circles made by the least and most refrangible Rays +75/8A and ((61-1/2)/8)A. These diameters are therefore to one another as +75 to 61-1/2 or 50 to 41, and their Squares as 2500 to 1681, that is, as +3 to 2 very nearly. Which proportion differs not much from the +proportion of the Diameters of the Circles made by the outmost red and +outmost violet, in the 13th Observation of the first part of this Book. + +_Obs._ 6. Placing my Eye where these Rings appear'd plainest, I saw the +Speculum tinged all over with Waves of Colours, (red, yellow, green, +blue;) like those which in the Observations of the first part of this +Book appeared between the Object-glasses, and upon Bubbles of Water, but +much larger. And after the manner of those, they were of various +magnitudes in various Positions of the Eye, swelling and shrinking as I +moved my Eye this way and that way. They were formed like Arcs of +concentrick Circles, as those were; and when my Eye was over against the +center of the concavity of the Speculum, (that is, 5 Feet and 10 Inches +distant from the Speculum,) their common center was in a right Line with +that center of concavity, and with the hole in the Window. But in other +postures of my Eye their center had other positions. They appear'd by +the Light of the Clouds propagated to the Speculum through the hole in +the Window; and when the Sun shone through that hole upon the Speculum, +his Light upon it was of the Colour of the Ring whereon it fell, but by +its splendor obscured the Rings made by the Light of the Clouds, unless +when the Speculum was removed to a great distance from the Window, so +that his Light upon it might be broad and faint. By varying the position +of my Eye, and moving it nearer to or farther from the direct beam of +the Sun's Light, the Colour of the Sun's reflected Light constantly +varied upon the Speculum, as it did upon my Eye, the same Colour always +appearing to a Bystander upon my Eye which to me appear'd upon the +Speculum. And thence I knew that the Rings of Colours upon the Chart +were made by these reflected Colours, propagated thither from the +Speculum in several Angles, and that their production depended not upon +the termination of Light and Shadow. + +_Obs._ 7. By the Analogy of all these Phænomena with those of the like +Rings of Colours described in the first part of this Book, it seemed to +me that these Colours were produced by this thick Plate of Glass, much +after the manner that those were produced by very thin Plates. For, upon +trial, I found that if the Quick-silver were rubb'd off from the +backside of the Speculum, the Glass alone would cause the same Rings of +Colours, but much more faint than before; and therefore the Phænomenon +depends not upon the Quick-silver, unless so far as the Quick-silver by +increasing the Reflexion of the backside of the Glass increases the +Light of the Rings of Colours. I found also that a Speculum of Metal +without Glass made some Years since for optical uses, and very well +wrought, produced none of those Rings; and thence I understood that +these Rings arise not from one specular Surface alone, but depend upon +the two Surfaces of the Plate of Glass whereof the Speculum was made, +and upon the thickness of the Glass between them. For as in the 7th and +19th Observations of the first part of this Book a thin Plate of Air, +Water, or Glass of an even thickness appeared of one Colour when the +Rays were perpendicular to it, of another when they were a little +oblique, of another when more oblique, of another when still more +oblique, and so on; so here, in the sixth Observation, the Light which +emerged out of the Glass in several Obliquities, made the Glass appear +of several Colours, and being propagated in those Obliquities to the +Chart, there painted Rings of those Colours. And as the reason why a +thin Plate appeared of several Colours in several Obliquities of the +Rays, was, that the Rays of one and the same sort are reflected by the +thin Plate at one obliquity and transmitted at another, and those of +other sorts transmitted where these are reflected, and reflected where +these are transmitted: So the reason why the thick Plate of Glass +whereof the Speculum was made did appear of various Colours in various +Obliquities, and in those Obliquities propagated those Colours to the +Chart, was, that the Rays of one and the same sort did at one Obliquity +emerge out of the Glass, at another did not emerge, but were reflected +back towards the Quick-silver by the hither Surface of the Glass, and +accordingly as the Obliquity became greater and greater, emerged and +were reflected alternately for many Successions; and that in one and the +same Obliquity the Rays of one sort were reflected, and those of another +transmitted. This is manifest by the fifth Observation of this part of +this Book. For in that Observation, when the Speculum was illuminated by +any one of the prismatick Colours, that Light made many Rings of the +same Colour upon the Chart with dark Intervals, and therefore at its +emergence out of the Speculum was alternately transmitted and not +transmitted from the Speculum to the Chart for many Successions, +according to the various Obliquities of its Emergence. And when the +Colour cast on the Speculum by the Prism was varied, the Rings became of +the Colour cast on it, and varied their bigness with their Colour, and +therefore the Light was now alternately transmitted and not transmitted +from the Speculum to the Chart at other Obliquities than before. It +seemed to me therefore that these Rings were of one and the same +original with those of thin Plates, but yet with this difference, that +those of thin Plates are made by the alternate Reflexions and +Transmissions of the Rays at the second Surface of the Plate, after one +passage through it; but here the Rays go twice through the Plate before +they are alternately reflected and transmitted. First, they go through +it from the first Surface to the Quick-silver, and then return through +it from the Quick-silver to the first Surface, and there are either +transmitted to the Chart or reflected back to the Quick-silver, +accordingly as they are in their Fits of easy Reflexion or Transmission +when they arrive at that Surface. For the Intervals of the Fits of the +Rays which fall perpendicularly on the Speculum, and are reflected back +in the same perpendicular Lines, by reason of the equality of these +Angles and Lines, are of the same length and number within the Glass +after Reflexion as before, by the 19th Proposition of the third part of +this Book. And therefore since all the Rays that enter through the +first Surface are in their Fits of easy Transmission at their entrance, +and as many of these as are reflected by the second are in their Fits of +easy Reflexion there, all these must be again in their Fits of easy +Transmission at their return to the first, and by consequence there go +out of the Glass to the Chart, and form upon it the white Spot of Light +in the center of the Rings. For the reason holds good in all sorts of +Rays, and therefore all sorts must go out promiscuously to that Spot, +and by their mixture cause it to be white. But the Intervals of the Fits +of those Rays which are reflected more obliquely than they enter, must +be greater after Reflexion than before, by the 15th and 20th +Propositions. And thence it may happen that the Rays at their return to +the first Surface, may in certain Obliquities be in Fits of easy +Reflexion, and return back to the Quick-silver, and in other +intermediate Obliquities be again in Fits of easy Transmission, and so +go out to the Chart, and paint on it the Rings of Colours about the +white Spot. And because the Intervals of the Fits at equal obliquities +are greater and fewer in the less refrangible Rays, and less and more +numerous in the more refrangible, therefore the less refrangible at +equal obliquities shall make fewer Rings than the more refrangible, and +the Rings made by those shall be larger than the like number of Rings +made by these; that is, the red Rings shall be larger than the yellow, +the yellow than the green, the green than the blue, and the blue than +the violet, as they were really found to be in the fifth Observation. +And therefore the first Ring of all Colours encompassing the white Spot +of Light shall be red without any violet within, and yellow, and green, +and blue in the middle, as it was found in the second Observation; and +these Colours in the second Ring, and those that follow, shall be more +expanded, till they spread into one another, and blend one another by +interfering. + +These seem to be the reasons of these Rings in general; and this put me +upon observing the thickness of the Glass, and considering whether the +dimensions and proportions of the Rings may be truly derived from it by +computation. + +_Obs._ 8. I measured therefore the thickness of this concavo-convex +Plate of Glass, and found it every where 1/4 of an Inch precisely. Now, +by the sixth Observation of the first Part of this Book, a thin Plate of +Air transmits the brightest Light of the first Ring, that is, the bright +yellow, when its thickness is the 1/89000th part of an Inch; and by the +tenth Observation of the same Part, a thin Plate of Glass transmits the +same Light of the same Ring, when its thickness is less in proportion of +the Sine of Refraction to the Sine of Incidence, that is, when its +thickness is the 11/1513000th or 1/137545th part of an Inch, supposing +the Sines are as 11 to 17. And if this thickness be doubled, it +transmits the same bright Light of the second Ring; if tripled, it +transmits that of the third, and so on; the bright yellow Light in all +these cases being in its Fits of Transmission. And therefore if its +thickness be multiplied 34386 times, so as to become 1/4 of an Inch, it +transmits the same bright Light of the 34386th Ring. Suppose this be the +bright yellow Light transmitted perpendicularly from the reflecting +convex side of the Glass through the concave side to the white Spot in +the center of the Rings of Colours on the Chart: And by a Rule in the +7th and 19th Observations in the first Part of this Book, and by the +15th and 20th Propositions of the third Part of this Book, if the Rays +be made oblique to the Glass, the thickness of the Glass requisite to +transmit the same bright Light of the same Ring in any obliquity, is to +this thickness of 1/4 of an Inch, as the Secant of a certain Angle to +the Radius, the Sine of which Angle is the first of an hundred and six +arithmetical Means between the Sines of Incidence and Refraction, +counted from the Sine of Incidence when the Refraction is made out of +any plated Body into any Medium encompassing it; that is, in this case, +out of Glass into Air. Now if the thickness of the Glass be increased by +degrees, so as to bear to its first thickness, (_viz._ that of a quarter +of an Inch,) the Proportions which 34386 (the number of Fits of the +perpendicular Rays in going through the Glass towards the white Spot in +the center of the Rings,) hath to 34385, 34384, 34383, and 34382, (the +numbers of the Fits of the oblique Rays in going through the Glass +towards the first, second, third, and fourth Rings of Colours,) and if +the first thickness be divided into 100000000 equal parts, the increased +thicknesses will be 100002908, 100005816, 100008725, and 100011633, and +the Angles of which these thicknesses are Secants will be 26´ 13´´, 37´ +5´´, 45´ 6´´, and 52´ 26´´, the Radius being 100000000; and the Sines of +these Angles are 762, 1079, 1321, and 1525, and the proportional Sines +of Refraction 1172, 1659, 2031, and 2345, the Radius being 100000. For +since the Sines of Incidence out of Glass into Air are to the Sines of +Refraction as 11 to 17, and to the above-mentioned Secants as 11 to the +first of 106 arithmetical Means between 11 and 17, that is, as 11 to +11-6/106, those Secants will be to the Sines of Refraction as 11-6/106, +to 17, and by this Analogy will give these Sines. So then, if the +obliquities of the Rays to the concave Surface of the Glass be such that +the Sines of their Refraction in passing out of the Glass through that +Surface into the Air be 1172, 1659, 2031, 2345, the bright Light of the +34386th Ring shall emerge at the thicknesses of the Glass, which are to +1/4 of an Inch as 34386 to 34385, 34384, 34383, 34382, respectively. And +therefore, if the thickness in all these Cases be 1/4 of an Inch (as it +is in the Glass of which the Speculum was made) the bright Light of the +34385th Ring shall emerge where the Sine of Refraction is 1172, and that +of the 34384th, 34383th, and 34382th Ring where the Sine is 1659, 2031, +and 2345 respectively. And in these Angles of Refraction the Light of +these Rings shall be propagated from the Speculum to the Chart, and +there paint Rings about the white central round Spot of Light which we +said was the Light of the 34386th Ring. And the Semidiameters of these +Rings shall subtend the Angles of Refraction made at the +Concave-Surface of the Speculum, and by consequence their Diameters +shall be to the distance of the Chart from the Speculum as those Sines +of Refraction doubled are to the Radius, that is, as 1172, 1659, 2031, +and 2345, doubled are to 100000. And therefore, if the distance of the +Chart from the Concave-Surface of the Speculum be six Feet (as it was in +the third of these Observations) the Diameters of the Rings of this +bright yellow Light upon the Chart shall be 1'688, 2'389, 2'925, 3'375 +Inches: For these Diameters are to six Feet, as the above-mention'd +Sines doubled are to the Radius. Now, these Diameters of the bright +yellow Rings, thus found by Computation are the very same with those +found in the third of these Observations by measuring them, _viz._ with +1-11/16, 2-3/8, 2-11/12, and 3-3/8 Inches, and therefore the Theory of +deriving these Rings from the thickness of the Plate of Glass of which +the Speculum was made, and from the Obliquity of the emerging Rays +agrees with the Observation. In this Computation I have equalled the +Diameters of the bright Rings made by Light of all Colours, to the +Diameters of the Rings made by the bright yellow. For this yellow makes +the brightest Part of the Rings of all Colours. If you desire the +Diameters of the Rings made by the Light of any other unmix'd Colour, +you may find them readily by putting them to the Diameters of the bright +yellow ones in a subduplicate Proportion of the Intervals of the Fits of +the Rays of those Colours when equally inclined to the refracting or +reflecting Surface which caused those Fits, that is, by putting the +Diameters of the Rings made by the Rays in the Extremities and Limits of +the seven Colours, red, orange, yellow, green, blue, indigo, violet, +proportional to the Cube-roots of the Numbers, 1, 8/9, 5/6, 3/4, 2/3, +3/5, 9/16, 1/2, which express the Lengths of a Monochord sounding the +Notes in an Eighth: For by this means the Diameters of the Rings of +these Colours will be found pretty nearly in the same Proportion to one +another, which they ought to have by the fifth of these Observations. + +And thus I satisfy'd my self, that these Rings were of the same kind and +Original with those of thin Plates, and by consequence that the Fits or +alternate Dispositions of the Rays to be reflected and transmitted are +propagated to great distances from every reflecting and refracting +Surface. But yet to put the matter out of doubt, I added the following +Observation. + +_Obs._ 9. If these Rings thus depend on the thickness of the Plate of +Glass, their Diameters at equal distances from several Speculums made of +such concavo-convex Plates of Glass as are ground on the same Sphere, +ought to be reciprocally in a subduplicate Proportion of the thicknesses +of the Plates of Glass. And if this Proportion be found true by +experience it will amount to a demonstration that these Rings (like +those formed in thin Plates) do depend on the thickness of the Glass. I +procured therefore another concavo-convex Plate of Glass ground on both +sides to the same Sphere with the former Plate. Its thickness was 5/62 +Parts of an Inch; and the Diameters of the three first bright Rings +measured between the brightest Parts of their Orbits at the distance of +six Feet from the Glass were 3·4-1/6·5-1/8· Inches. Now, the thickness +of the other Glass being 1/4 of an Inch was to the thickness of this +Glass as 1/4 to 5/62, that is as 31 to 10, or 310000000 to 100000000, +and the Roots of these Numbers are 17607 and 10000, and in the +Proportion of the first of these Roots to the second are the Diameters +of the bright Rings made in this Observation by the thinner Glass, +3·4-1/6·5-1/8, to the Diameters of the same Rings made in the third of +these Observations by the thicker Glass 1-11/16, 2-3/8. 2-11/12, that +is, the Diameters of the Rings are reciprocally in a subduplicate +Proportion of the thicknesses of the Plates of Glass. + +So then in Plates of Glass which are alike concave on one side, and +alike convex on the other side, and alike quick-silver'd on the convex +sides, and differ in nothing but their thickness, the Diameters of the +Rings are reciprocally in a subduplicate Proportion of the thicknesses +of the Plates. And this shews sufficiently that the Rings depend on both +the Surfaces of the Glass. They depend on the convex Surface, because +they are more luminous when that Surface is quick-silver'd over than +when it is without Quick-silver. They depend also upon the concave +Surface, because without that Surface a Speculum makes them not. They +depend on both Surfaces, and on the distances between them, because +their bigness is varied by varying only that distance. And this +dependence is of the same kind with that which the Colours of thin +Plates have on the distance of the Surfaces of those Plates, because the +bigness of the Rings, and their Proportion to one another, and the +variation of their bigness arising from the variation of the thickness +of the Glass, and the Orders of their Colours, is such as ought to +result from the Propositions in the end of the third Part of this Book, +derived from the Phænomena of the Colours of thin Plates set down in the +first Part. + +There are yet other Phænomena of these Rings of Colours, but such as +follow from the same Propositions, and therefore confirm both the Truth +of those Propositions, and the Analogy between these Rings and the Rings +of Colours made by very thin Plates. I shall subjoin some of them. + +_Obs._ 10. When the beam of the Sun's Light was reflected back from the +Speculum not directly to the hole in the Window, but to a place a little +distant from it, the common center of that Spot, and of all the Rings of +Colours fell in the middle way between the beam of the incident Light, +and the beam of the reflected Light, and by consequence in the center of +the spherical concavity of the Speculum, whenever the Chart on which the +Rings of Colours fell was placed at that center. And as the beam of +reflected Light by inclining the Speculum receded more and more from the +beam of incident Light and from the common center of the colour'd Rings +between them, those Rings grew bigger and bigger, and so also did the +white round Spot, and new Rings of Colours emerged successively out of +their common center, and the white Spot became a white Ring +encompassing them; and the incident and reflected beams of Light always +fell upon the opposite parts of this white Ring, illuminating its +Perimeter like two mock Suns in the opposite parts of an Iris. So then +the Diameter of this Ring, measured from the middle of its Light on one +side to the middle of its Light on the other side, was always equal to +the distance between the middle of the incident beam of Light, and the +middle of the reflected beam measured at the Chart on which the Rings +appeared: And the Rays which form'd this Ring were reflected by the +Speculum in Angles equal to their Angles of Incidence, and by +consequence to their Angles of Refraction at their entrance into the +Glass, but yet their Angles of Reflexion were not in the same Planes +with their Angles of Incidence. + +_Obs._ 11. The Colours of the new Rings were in a contrary order to +those of the former, and arose after this manner. The white round Spot +of Light in the middle of the Rings continued white to the center till +the distance of the incident and reflected beams at the Chart was about +7/8 parts of an Inch, and then it began to grow dark in the middle. And +when that distance was about 1-3/16 of an Inch, the white Spot was +become a Ring encompassing a dark round Spot which in the middle +inclined to violet and indigo. And the luminous Rings encompassing it +were grown equal to those dark ones which in the four first Observations +encompassed them, that is to say, the white Spot was grown a white Ring +equal to the first of those dark Rings, and the first of those luminous +Rings was now grown equal to the second of those dark ones, and the +second of those luminous ones to the third of those dark ones, and so +on. For the Diameters of the luminous Rings were now 1-3/16, 2-1/16, +2-2/3, 3-3/20, &c. Inches. + +When the distance between the incident and reflected beams of Light +became a little bigger, there emerged out of the middle of the dark Spot +after the indigo a blue, and then out of that blue a pale green, and +soon after a yellow and red. And when the Colour at the center was +brightest, being between yellow and red, the bright Rings were grown +equal to those Rings which in the four first Observations next +encompassed them; that is to say, the white Spot in the middle of those +Rings was now become a white Ring equal to the first of those bright +Rings, and the first of those bright ones was now become equal to the +second of those, and so on. For the Diameters of the white Ring, and of +the other luminous Rings encompassing it, were now 1-11/16, 2-3/8, +2-11/12, 3-3/8, &c. or thereabouts. + +When the distance of the two beams of Light at the Chart was a little +more increased, there emerged out of the middle in order after the red, +a purple, a blue, a green, a yellow, and a red inclining much to purple, +and when the Colour was brightest being between yellow and red, the +former indigo, blue, green, yellow and red, were become an Iris or Ring +of Colours equal to the first of those luminous Rings which appeared in +the four first Observations, and the white Ring which was now become +the second of the luminous Rings was grown equal to the second of those, +and the first of those which was now become the third Ring was become +equal to the third of those, and so on. For their Diameters were +1-11/16, 2-3/8, 2-11/12, 3-3/8 Inches, the distance of the two beams of +Light, and the Diameter of the white Ring being 2-3/8 Inches. + +When these two beams became more distant there emerged out of the middle +of the purplish red, first a darker round Spot, and then out of the +middle of that Spot a brighter. And now the former Colours (purple, +blue, green, yellow, and purplish red) were become a Ring equal to the +first of the bright Rings mentioned in the four first Observations, and +the Rings about this Ring were grown equal to the Rings about that +respectively; the distance between the two beams of Light and the +Diameter of the white Ring (which was now become the third Ring) being +about 3 Inches. + +The Colours of the Rings in the middle began now to grow very dilute, +and if the distance between the two Beams was increased half an Inch, or +an Inch more, they vanish'd whilst the white Ring, with one or two of +the Rings next it on either side, continued still visible. But if the +distance of the two beams of Light was still more increased, these also +vanished: For the Light which coming from several parts of the hole in +the Window fell upon the Speculum in several Angles of Incidence, made +Rings of several bignesses, which diluted and blotted out one another, +as I knew by intercepting some part of that Light. For if I intercepted +that part which was nearest to the Axis of the Speculum the Rings would +be less, if the other part which was remotest from it they would be +bigger. + +_Obs._ 12. When the Colours of the Prism were cast successively on the +Speculum, that Ring which in the two last Observations was white, was of +the same bigness in all the Colours, but the Rings without it were +greater in the green than in the blue, and still greater in the yellow, +and greatest in the red. And, on the contrary, the Rings within that +white Circle were less in the green than in the blue, and still less in +the yellow, and least in the red. For the Angles of Reflexion of those +Rays which made this Ring, being equal to their Angles of Incidence, the +Fits of every reflected Ray within the Glass after Reflexion are equal +in length and number to the Fits of the same Ray within the Glass before +its Incidence on the reflecting Surface. And therefore since all the +Rays of all sorts at their entrance into the Glass were in a Fit of +Transmission, they were also in a Fit of Transmission at their returning +to the same Surface after Reflexion; and by consequence were +transmitted, and went out to the white Ring on the Chart. This is the +reason why that Ring was of the same bigness in all the Colours, and why +in a mixture of all it appears white. But in Rays which are reflected in +other Angles, the Intervals of the Fits of the least refrangible being +greatest, make the Rings of their Colour in their progress from this +white Ring, either outwards or inwards, increase or decrease by the +greatest steps; so that the Rings of this Colour without are greatest, +and within least. And this is the reason why in the last Observation, +when the Speculum was illuminated with white Light, the exterior Rings +made by all Colours appeared red without and blue within, and the +interior blue without and red within. + +These are the Phænomena of thick convexo-concave Plates of Glass, which +are every where of the same thickness. There are yet other Phænomena +when these Plates are a little thicker on one side than on the other, +and others when the Plates are more or less concave than convex, or +plano-convex, or double-convex. For in all these cases the Plates make +Rings of Colours, but after various manners; all which, so far as I have +yet observed, follow from the Propositions in the end of the third part +of this Book, and so conspire to confirm the truth of those +Propositions. But the Phænomena are too various, and the Calculations +whereby they follow from those Propositions too intricate to be here +prosecuted. I content my self with having prosecuted this kind of +Phænomena so far as to discover their Cause, and by discovering it to +ratify the Propositions in the third Part of this Book. + +_Obs._ 13. As Light reflected by a Lens quick-silver'd on the backside +makes the Rings of Colours above described, so it ought to make the like +Rings of Colours in passing through a drop of Water. At the first +Reflexion of the Rays within the drop, some Colours ought to be +transmitted, as in the case of a Lens, and others to be reflected back +to the Eye. For instance, if the Diameter of a small drop or globule of +Water be about the 500th part of an Inch, so that a red-making Ray in +passing through the middle of this globule has 250 Fits of easy +Transmission within the globule, and that all the red-making Rays which +are at a certain distance from this middle Ray round about it have 249 +Fits within the globule, and all the like Rays at a certain farther +distance round about it have 248 Fits, and all those at a certain +farther distance 247 Fits, and so on; these concentrick Circles of Rays +after their transmission, falling on a white Paper, will make +concentrick Rings of red upon the Paper, supposing the Light which +passes through one single globule, strong enough to be sensible. And, in +like manner, the Rays of other Colours will make Rings of other Colours. +Suppose now that in a fair Day the Sun shines through a thin Cloud of +such globules of Water or Hail, and that the globules are all of the +same bigness; and the Sun seen through this Cloud shall appear +encompassed with the like concentrick Rings of Colours, and the Diameter +of the first Ring of red shall be 7-1/4 Degrees, that of the second +10-1/4 Degrees, that of the third 12 Degrees 33 Minutes. And accordingly +as the Globules of Water are bigger or less, the Rings shall be less or +bigger. This is the Theory, and Experience answers it. For in _June_ +1692, I saw by reflexion in a Vessel of stagnating Water three Halos, +Crowns, or Rings of Colours about the Sun, like three little Rain-bows, +concentrick to his Body. The Colours of the first or innermost Crown +were blue next the Sun, red without, and white in the middle between the +blue and red. Those of the second Crown were purple and blue within, and +pale red without, and green in the middle. And those of the third were +pale blue within, and pale red without; these Crowns enclosed one +another immediately, so that their Colours proceeded in this continual +order from the Sun outward: blue, white, red; purple, blue, green, pale +yellow and red; pale blue, pale red. The Diameter of the second Crown +measured from the middle of the yellow and red on one side of the Sun, +to the middle of the same Colour on the other side was 9-1/3 Degrees, or +thereabouts. The Diameters of the first and third I had not time to +measure, but that of the first seemed to be about five or six Degrees, +and that of the third about twelve. The like Crowns appear sometimes +about the Moon; for in the beginning of the Year 1664, _Febr._ 19th at +Night, I saw two such Crowns about her. The Diameter of the first or +innermost was about three Degrees, and that of the second about five +Degrees and an half. Next about the Moon was a Circle of white, and next +about that the inner Crown, which was of a bluish green within next the +white, and of a yellow and red without, and next about these Colours +were blue and green on the inside of the outward Crown, and red on the +outside of it. At the same time there appear'd a Halo about 22 Degrees +35´ distant from the center of the Moon. It was elliptical, and its long +Diameter was perpendicular to the Horizon, verging below farthest from +the Moon. I am told that the Moon has sometimes three or more +concentrick Crowns of Colours encompassing one another next about her +Body. The more equal the globules of Water or Ice are to one another, +the more Crowns of Colours will appear, and the Colours will be the more +lively. The Halo at the distance of 22-1/2 Degrees from the Moon is of +another sort. By its being oval and remoter from the Moon below than +above, I conclude, that it was made by Refraction in some sort of Hail +or Snow floating in the Air in an horizontal posture, the refracting +Angle being about 58 or 60 Degrees. + + + + +THE + +THIRD BOOK + +OF + +OPTICKS + + +_PART I._ + +_Observations concerning the Inflexions of the Rays of Light, and the +Colours made thereby._ + +Grimaldo has inform'd us, that if a beam of the Sun's Light be let into +a dark Room through a very small hole, the Shadows of things in this +Light will be larger than they ought to be if the Rays went on by the +Bodies in straight Lines, and that these Shadows have three parallel +Fringes, Bands or Ranks of colour'd Light adjacent to them. But if the +Hole be enlarged the Fringes grow broad and run into one another, so +that they cannot be distinguish'd. These broad Shadows and Fringes have +been reckon'd by some to proceed from the ordinary refraction of the +Air, but without due examination of the Matter. For the circumstances of +the Phænomenon, so far as I have observed them, are as follows. + +_Obs._ 1. I made in a piece of Lead a small Hole with a Pin, whose +breadth was the 42d part of an Inch. For 21 of those Pins laid together +took up the breadth of half an Inch. Through this Hole I let into my +darken'd Chamber a beam of the Sun's Light, and found that the Shadows +of Hairs, Thred, Pins, Straws, and such like slender Substances placed +in this beam of Light, were considerably broader than they ought to be, +if the Rays of Light passed on by these Bodies in right Lines. And +particularly a Hair of a Man's Head, whose breadth was but the 280th +part of an Inch, being held in this Light, at the distance of about +twelve Feet from the Hole, did cast a Shadow which at the distance of +four Inches from the Hair was the sixtieth part of an Inch broad, that +is, above four times broader than the Hair, and at the distance of two +Feet from the Hair was about the eight and twentieth part of an Inch +broad, that is, ten times broader than the Hair, and at the distance of +ten Feet was the eighth part of an Inch broad, that is 35 times broader. + +Nor is it material whether the Hair be encompassed with Air, or with any +other pellucid Substance. For I wetted a polish'd Plate of Glass, and +laid the Hair in the Water upon the Glass, and then laying another +polish'd Plate of Glass upon it, so that the Water might fill up the +space between the Glasses, I held them in the aforesaid beam of Light, +so that the Light might pass through them perpendicularly, and the +Shadow of the Hair was at the same distances as big as before. The +Shadows of Scratches made in polish'd Plates of Glass were also much +broader than they ought to be, and the Veins in polish'd Plates of Glass +did also cast the like broad Shadows. And therefore the great breadth of +these Shadows proceeds from some other cause than the Refraction of the +Air. + +Let the Circle X [in _Fig._ 1.] represent the middle of the Hair; ADG, +BEH, CFI, three Rays passing by one side of the Hair at several +distances; KNQ, LOR, MPS, three other Rays passing by the other side of +the Hair at the like distances; D, E, F, and N, O, P, the places where +the Rays are bent in their passage by the Hair; G, H, I, and Q, R, S, +the places where the Rays fall on a Paper GQ; IS the breadth of the +Shadow of the Hair cast on the Paper, and TI, VS, two Rays passing to +the Points I and S without bending when the Hair is taken away. And it's +manifest that all the Light between these two Rays TI and VS is bent in +passing by the Hair, and turned aside from the Shadow IS, because if any +part of this Light were not bent it would fall on the Paper within the +Shadow, and there illuminate the Paper, contrary to experience. And +because when the Paper is at a great distance from the Hair, the Shadow +is broad, and therefore the Rays TI and VS are at a great distance from +one another, it follows that the Hair acts upon the Rays of Light at a +good distance in their passing by it. But the Action is strongest on the +Rays which pass by at least distances, and grows weaker and weaker +accordingly as the Rays pass by at distances greater and greater, as is +represented in the Scheme: For thence it comes to pass, that the Shadow +of the Hair is much broader in proportion to the distance of the Paper +from the Hair, when the Paper is nearer the Hair, than when it is at a +great distance from it. + +_Obs._ 2. The Shadows of all Bodies (Metals, Stones, Glass, Wood, Horn, +Ice, &c.) in this Light were border'd with three Parallel Fringes or +Bands of colour'd Light, whereof that which was contiguous to the Shadow +was broadest and most luminous, and that which was remotest from it was +narrowest, and so faint, as not easily to be visible. It was difficult +to distinguish the Colours, unless when the Light fell very obliquely +upon a smooth Paper, or some other smooth white Body, so as to make them +appear much broader than they would otherwise do. And then the Colours +were plainly visible in this Order: The first or innermost Fringe was +violet and deep blue next the Shadow, and then light blue, green, and +yellow in the middle, and red without. The second Fringe was almost +contiguous to the first, and the third to the second, and both were blue +within, and yellow and red without, but their Colours were very faint, +especially those of the third. The Colours therefore proceeded in this +order from the Shadow; violet, indigo, pale blue, green, yellow, red; +blue, yellow, red; pale blue, pale yellow and red. The Shadows made by +Scratches and Bubbles in polish'd Plates of Glass were border'd with the +like Fringes of colour'd Light. And if Plates of Looking-glass sloop'd +off near the edges with a Diamond-cut, be held in the same beam of +Light, the Light which passes through the parallel Planes of the Glass +will be border'd with the like Fringes of Colours where those Planes +meet with the Diamond-cut, and by this means there will sometimes appear +four or five Fringes of Colours. Let AB, CD [in _Fig._ 2.] represent the +parallel Planes of a Looking-glass, and BD the Plane of the Diamond-cut, +making at B a very obtuse Angle with the Plane AB. And let all the Light +between the Rays ENI and FBM pass directly through the parallel Planes +of the Glass, and fall upon the Paper between I and M, and all the Light +between the Rays GO and HD be refracted by the oblique Plane of the +Diamond-cut BD, and fall upon the Paper between K and L; and the Light +which passes directly through the parallel Planes of the Glass, and +falls upon the Paper between I and M, will be border'd with three or +more Fringes at M. + +[Illustration: FIG. 1.] + +[Illustration: FIG. 2.] + +So by looking on the Sun through a Feather or black Ribband held close +to the Eye, several Rain-bows will appear; the Shadows which the Fibres +or Threds cast on the _Tunica Retina_, being border'd with the like +Fringes of Colours. + +_Obs._ 3. When the Hair was twelve Feet distant from this Hole, and its +Shadow fell obliquely upon a flat white Scale of Inches and Parts of an +Inch placed half a Foot beyond it, and also when the Shadow fell +perpendicularly upon the same Scale placed nine Feet beyond it; I +measured the breadth of the Shadow and Fringes as accurately as I could, +and found them in Parts of an Inch as follows. + +-------------------------------------------+-----------+-------- + | half a | Nine + At the Distance of | Foot | Feet +-------------------------------------------+-----------+-------- +The breadth of the Shadow | 1/54 | 1/9 +-------------------------------------------+-----------+-------- +The breadth between the Middles of the | 1/38 | + brightest Light of the innermost Fringes | or | + on either side the Shadow | 1/39 | 7/50 +-------------------------------------------+-----------+-------- +The breadth between the Middles of the | | + brightest Light of the middlemost Fringes| | + on either side the Shadow | 1/23-1/2 | 4/17 +-------------------------------------------+-----------+-------- +The breadth between the Middles of the | 1/18 | + brightest Light of the outmost Fringes | or | + on either side the Shadow | 1/18-1/2 | 3/10 +-------------------------------------------+-----------+-------- +The distance between the Middles of the | | + brightest Light of the first and second | | + Fringes | 1/120 | 1/21 +-------------------------------------------+-----------+-------- +The distance between the Middles of the | | + brightest Light of the second and third | | + Fringes | 1/170 | 1/31 +-------------------------------------------+-----------+-------- +The breadth of the luminous Part (green, | | + white, yellow, and red) of the first | | + Fringe | 1/170 | 1/32 +-------------------------------------------+-----------+-------- +The breadth of the darker Space between | | + the first and second Fringes | 1/240 | 1/45 +-------------------------------------------+-----------+-------- +The breadth of the luminous Part of the | | + second Fringe | 1/290 | 1/55 +-------------------------------------------+-----------+-------- +The breadth of the darker Space between | | + the second and third Fringes | 1/340 | 1/63 +-------------------------------------------+-----------+-------- + +These Measures I took by letting the Shadow of the Hair, at half a Foot +distance, fall so obliquely on the Scale, as to appear twelve times +broader than when it fell perpendicularly on it at the same distance, +and setting down in this Table the twelfth part of the Measures I then +took. + +_Obs._ 4. When the Shadow and Fringes were cast obliquely upon a smooth +white Body, and that Body was removed farther and farther from the Hair, +the first Fringe began to appear and look brighter than the rest of the +Light at the distance of less than a quarter of an Inch from the Hair, +and the dark Line or Shadow between that and the second Fringe began to +appear at a less distance from the Hair than that of the third part of +an Inch. The second Fringe began to appear at a distance from the Hair +of less than half an Inch, and the Shadow between that and the third +Fringe at a distance less than an inch, and the third Fringe at a +distance less than three Inches. At greater distances they became much +more sensible, but kept very nearly the same proportion of their +breadths and intervals which they had at their first appearing. For the +distance between the middle of the first, and middle of the second +Fringe, was to the distance between the middle of the second and middle +of the third Fringe, as three to two, or ten to seven. And the last of +these two distances was equal to the breadth of the bright Light or +luminous part of the first Fringe. And this breadth was to the breadth +of the bright Light of the second Fringe as seven to four, and to the +dark Interval of the first and second Fringe as three to two, and to +the like dark Interval between the second and third as two to one. For +the breadths of the Fringes seem'd to be in the progression of the +Numbers 1, sqrt(1/3), sqrt(1/5), and their Intervals to be in the +same progression with them; that is, the Fringes and their Intervals +together to be in the continual progression of the Numbers 1, +sqrt(1/2), sqrt(1/3), sqrt(1/4), sqrt(1/5), or thereabouts. And +these Proportions held the same very nearly at all distances from the +Hair; the dark Intervals of the Fringes being as broad in proportion to +the breadth of the Fringes at their first appearance as afterwards at +great distances from the Hair, though not so dark and distinct. + +_Obs._ 5. The Sun shining into my darken'd Chamber through a hole a +quarter of an Inch broad, I placed at the distance of two or three Feet +from the Hole a Sheet of Pasteboard, which was black'd all over on both +sides, and in the middle of it had a hole about three quarters of an +Inch square for the Light to pass through. And behind the hole I +fasten'd to the Pasteboard with Pitch the blade of a sharp Knife, to +intercept some part of the Light which passed through the hole. The +Planes of the Pasteboard and blade of the Knife were parallel to one +another, and perpendicular to the Rays. And when they were so placed +that none of the Sun's Light fell on the Pasteboard, but all of it +passed through the hole to the Knife, and there part of it fell upon the +blade of the Knife, and part of it passed by its edge; I let this part +of the Light which passed by, fall on a white Paper two or three Feet +beyond the Knife, and there saw two streams of faint Light shoot out +both ways from the beam of Light into the shadow, like the Tails of +Comets. But because the Sun's direct Light by its brightness upon the +Paper obscured these faint streams, so that I could scarce see them, I +made a little hole in the midst of the Paper for that Light to pass +through and fall on a black Cloth behind it; and then I saw the two +streams plainly. They were like one another, and pretty nearly equal in +length, and breadth, and quantity of Light. Their Light at that end next +the Sun's direct Light was pretty strong for the space of about a +quarter of an Inch, or half an Inch, and in all its progress from that +direct Light decreased gradually till it became insensible. The whole +length of either of these streams measured upon the paper at the +distance of three Feet from the Knife was about six or eight Inches; so +that it subtended an Angle at the edge of the Knife of about 10 or 12, +or at most 14 Degrees. Yet sometimes I thought I saw it shoot three or +four Degrees farther, but with a Light so very faint that I could scarce +perceive it, and suspected it might (in some measure at least) arise +from some other cause than the two streams did. For placing my Eye in +that Light beyond the end of that stream which was behind the Knife, and +looking towards the Knife, I could see a line of Light upon its edge, +and that not only when my Eye was in the line of the Streams, but also +when it was without that line either towards the point of the Knife, or +towards the handle. This line of Light appear'd contiguous to the edge +of the Knife, and was narrower than the Light of the innermost Fringe, +and narrowest when my Eye was farthest from the direct Light, and +therefore seem'd to pass between the Light of that Fringe and the edge +of the Knife, and that which passed nearest the edge to be most bent, +though not all of it. + +_Obs._ 6. I placed another Knife by this, so that their edges might be +parallel, and look towards one another, and that the beam of Light might +fall upon both the Knives, and some part of it pass between their edges. +And when the distance of their edges was about the 400th part of an +Inch, the stream parted in the middle, and left a Shadow between the two +parts. This Shadow was so black and dark that all the Light which passed +between the Knives seem'd to be bent, and turn'd aside to the one hand +or to the other. And as the Knives still approach'd one another the +Shadow grew broader, and the streams shorter at their inward ends which +were next the Shadow, until upon the contact of the Knives the whole +Light vanish'd, leaving its place to the Shadow. + +And hence I gather that the Light which is least bent, and goes to the +inward ends of the streams, passes by the edges of the Knives at the +greatest distance, and this distance when the Shadow begins to appear +between the streams, is about the 800th part of an Inch. And the Light +which passes by the edges of the Knives at distances still less and +less, is more and more bent, and goes to those parts of the streams +which are farther and farther from the direct Light; because when the +Knives approach one another till they touch, those parts of the streams +vanish last which are farthest from the direct Light. + +_Obs._ 7. In the fifth Observation the Fringes did not appear, but by +reason of the breadth of the hole in the Window became so broad as to +run into one another, and by joining, to make one continued Light in the +beginning of the streams. But in the sixth, as the Knives approached one +another, a little before the Shadow appeared between the two streams, +the Fringes began to appear on the inner ends of the Streams on either +side of the direct Light; three on one side made by the edge of one +Knife, and three on the other side made by the edge of the other Knife. +They were distinctest when the Knives were placed at the greatest +distance from the hole in the Window, and still became more distinct by +making the hole less, insomuch that I could sometimes see a faint +lineament of a fourth Fringe beyond the three above mention'd. And as +the Knives continually approach'd one another, the Fringes grew +distincter and larger, until they vanish'd. The outmost Fringe vanish'd +first, and the middlemost next, and the innermost last. And after they +were all vanish'd, and the line of Light which was in the middle between +them was grown very broad, enlarging it self on both sides into the +streams of Light described in the fifth Observation, the above-mention'd +Shadow began to appear in the middle of this line, and divide it along +the middle into two lines of Light, and increased until the whole Light +vanish'd. This enlargement of the Fringes was so great that the Rays +which go to the innermost Fringe seem'd to be bent above twenty times +more when this Fringe was ready to vanish, than when one of the Knives +was taken away. + +And from this and the former Observation compared, I gather, that the +Light of the first Fringe passed by the edge of the Knife at a distance +greater than the 800th part of an Inch, and the Light of the second +Fringe passed by the edge of the Knife at a greater distance than the +Light of the first Fringe did, and that of the third at a greater +distance than that of the second, and that of the streams of Light +described in the fifth and sixth Observations passed by the edges of the +Knives at less distances than that of any of the Fringes. + +_Obs._ 8. I caused the edges of two Knives to be ground truly strait, +and pricking their points into a Board so that their edges might look +towards one another, and meeting near their points contain a rectilinear +Angle, I fasten'd their Handles together with Pitch to make this Angle +invariable. The distance of the edges of the Knives from one another at +the distance of four Inches from the angular Point, where the edges of +the Knives met, was the eighth part of an Inch; and therefore the Angle +contain'd by the edges was about one Degree 54: The Knives thus fix'd +together I placed in a beam of the Sun's Light, let into my darken'd +Chamber through a Hole the 42d Part of an Inch wide, at the distance of +10 or 15 Feet from the Hole, and let the Light which passed between +their edges fall very obliquely upon a smooth white Ruler at the +distance of half an Inch, or an Inch from the Knives, and there saw the +Fringes by the two edges of the Knives run along the edges of the +Shadows of the Knives in Lines parallel to those edges without growing +sensibly broader, till they met in Angles equal to the Angle contained +by the edges of the Knives, and where they met and joined they ended +without crossing one another. But if the Ruler was held at a much +greater distance from the Knives, the Fringes where they were farther +from the Place of their Meeting, were a little narrower, and became +something broader and broader as they approach'd nearer and nearer to +one another, and after they met they cross'd one another, and then +became much broader than before. + +Whence I gather that the distances at which the Fringes pass by the +Knives are not increased nor alter'd by the approach of the Knives, but +the Angles in which the Rays are there bent are much increased by that +approach; and that the Knife which is nearest any Ray determines which +way the Ray shall be bent, and the other Knife increases the bent. + +_Obs._ 9. When the Rays fell very obliquely upon the Ruler at the +distance of the third Part of an Inch from the Knives, the dark Line +between the first and second Fringe of the Shadow of one Knife, and the +dark Line between the first and second Fringe of the Shadow of the other +knife met with one another, at the distance of the fifth Part of an Inch +from the end of the Light which passed between the Knives at the +concourse of their edges. And therefore the distance of the edges of the +Knives at the meeting of these dark Lines was the 160th Part of an Inch. +For as four Inches to the eighth Part of an Inch, so is any Length of +the edges of the Knives measured from the point of their concourse to +the distance of the edges of the Knives at the end of that Length, and +so is the fifth Part of an Inch to the 160th Part. So then the dark +Lines above-mention'd meet in the middle of the Light which passes +between the Knives where they are distant the 160th Part of an Inch, and +the one half of that Light passes by the edge of one Knife at a distance +not greater than the 320th Part of an Inch, and falling upon the Paper +makes the Fringes of the Shadow of that Knife, and the other half passes +by the edge of the other Knife, at a distance not greater than the 320th +Part of an Inch, and falling upon the Paper makes the Fringes of the +Shadow of the other Knife. But if the Paper be held at a distance from +the Knives greater than the third Part of an Inch, the dark Lines +above-mention'd meet at a greater distance than the fifth Part of an +Inch from the end of the Light which passed between the Knives at the +concourse of their edges; and therefore the Light which falls upon the +Paper where those dark Lines meet passes between the Knives where the +edges are distant above the 160th part of an Inch. + +For at another time, when the two Knives were distant eight Feet and +five Inches from the little hole in the Window, made with a small Pin as +above, the Light which fell upon the Paper where the aforesaid dark +lines met, passed between the Knives, where the distance between their +edges was as in the following Table, when the distance of the Paper from +the Knives was also as follows. + +-----------------------------+------------------------------ + | Distances between the edges + Distances of the Paper | of the Knives in millesimal + from the Knives in Inches. | parts of an Inch. +-----------------------------+------------------------------ + 1-1/2. | 0'012 + 3-1/3. | 0'020 + 8-3/5. | 0'034 + 32. | 0'057 + 96. | 0'081 + 131. | 0'087 +_____________________________|______________________________ + +And hence I gather, that the Light which makes the Fringes upon the +Paper is not the same Light at all distances of the Paper from the +Knives, but when the Paper is held near the Knives, the Fringes are made +by Light which passes by the edges of the Knives at a less distance, and +is more bent than when the Paper is held at a greater distance from the +Knives. + +[Illustration: FIG. 3.] + +_Obs._ 10. When the Fringes of the Shadows of the Knives fell +perpendicularly upon a Paper at a great distance from the Knives, they +were in the form of Hyperbola's, and their Dimensions were as follows. +Let CA, CB [in _Fig._ 3.] represent Lines drawn upon the Paper parallel +to the edges of the Knives, and between which all the Light would fall, +if it passed between the edges of the Knives without inflexion; DE a +Right Line drawn through C making the Angles ACD, BCE, equal to one +another, and terminating all the Light which falls upon the Paper from +the point where the edges of the Knives meet; _eis_, _fkt_, and _glv_, +three hyperbolical Lines representing the Terminus of the Shadow of one +of the Knives, the dark Line between the first and second Fringes of +that Shadow, and the dark Line between the second and third Fringes of +the same Shadow; _xip_, _ykq_, and _zlr_, three other hyperbolical Lines +representing the Terminus of the Shadow of the other Knife, the dark +Line between the first and second Fringes of that Shadow, and the dark +line between the second and third Fringes of the same Shadow. And +conceive that these three Hyperbola's are like and equal to the former +three, and cross them in the points _i_, _k_, and _l_, and that the +Shadows of the Knives are terminated and distinguish'd from the first +luminous Fringes by the lines _eis_ and _xip_, until the meeting and +crossing of the Fringes, and then those lines cross the Fringes in the +form of dark lines, terminating the first luminous Fringes within side, +and distinguishing them from another Light which begins to appear at +_i_, and illuminates all the triangular space _ip_DE_s_ comprehended by +these dark lines, and the right line DE. Of these Hyperbola's one +Asymptote is the line DE, and their other Asymptotes are parallel to the +lines CA and CB. Let _rv_ represent a line drawn any where upon the +Paper parallel to the Asymptote DE, and let this line cross the right +lines AC in _m_, and BC in _n_, and the six dark hyperbolical lines in +_p_, _q_, _r_; _s_, _t_, _v_; and by measuring the distances _ps_, _qt_, +_rv_, and thence collecting the lengths of the Ordinates _np_, _nq_, +_nr_ or _ms_, _mt_, _mv_, and doing this at several distances of the +line _rv_ from the Asymptote DD, you may find as many points of these +Hyperbola's as you please, and thereby know that these curve lines are +Hyperbola's differing little from the conical Hyperbola. And by +measuring the lines C_i_, C_k_, C_l_, you may find other points of these +Curves. + +For instance; when the Knives were distant from the hole in the Window +ten Feet, and the Paper from the Knives nine Feet, and the Angle +contained by the edges of the Knives to which the Angle ACB is equal, +was subtended by a Chord which was to the Radius as 1 to 32, and the +distance of the line _rv_ from the Asymptote DE was half an Inch: I +measured the lines _ps_, _qt_, _rv_, and found them 0'35, 0'65, 0'98 +Inches respectively; and by adding to their halfs the line 1/2 _mn_, +(which here was the 128th part of an Inch, or 0'0078 Inches,) the Sums +_np_, _nq_, _nr_, were 0'1828, 0'3328, 0'4978 Inches. I measured also +the distances of the brightest parts of the Fringes which run between +_pq_ and _st_, _qr_ and _tv_, and next beyond _r_ and _v_, and found +them 0'5, 0'8, and 1'17 Inches. + +_Obs._ 11. The Sun shining into my darken'd Room through a small round +hole made in a Plate of Lead with a slender Pin, as above; I placed at +the hole a Prism to refract the Light, and form on the opposite Wall the +Spectrum of Colours, described in the third Experiment of the first +Book. And then I found that the Shadows of all Bodies held in the +colour'd Light between the Prism and the Wall, were border'd with +Fringes of the Colour of that Light in which they were held. In the full +red Light they were totally red without any sensible blue or violet, and +in the deep blue Light they were totally blue without any sensible red +or yellow; and so in the green Light they were totally green, excepting +a little yellow and blue, which were mixed in the green Light of the +Prism. And comparing the Fringes made in the several colour'd Lights, I +found that those made in the red Light were largest, those made in the +violet were least, and those made in the green were of a middle bigness. +For the Fringes with which the Shadow of a Man's Hair were bordered, +being measured cross the Shadow at the distance of six Inches from the +Hair, the distance between the middle and most luminous part of the +first or innermost Fringe on one side of the Shadow, and that of the +like Fringe on the other side of the Shadow, was in the full red Light +1/37-1/4 of an Inch, and in the full violet 7/46. And the like distance +between the middle and most luminous parts of the second Fringes on +either side the Shadow was in the full red Light 1/22, and in the violet +1/27 of an Inch. And these distances of the Fringes held the same +proportion at all distances from the Hair without any sensible +variation. + +So then the Rays which made these Fringes in the red Light passed by the +Hair at a greater distance than those did which made the like Fringes in +the violet; and therefore the Hair in causing these Fringes acted alike +upon the red Light or least refrangible Rays at a greater distance, and +upon the violet or most refrangible Rays at a less distance, and by +those actions disposed the red Light into Larger Fringes, and the violet +into smaller, and the Lights of intermediate Colours into Fringes of +intermediate bignesses without changing the Colour of any sort of Light. + +When therefore the Hair in the first and second of these Observations +was held in the white beam of the Sun's Light, and cast a Shadow which +was border'd with three Fringes of coloured Light, those Colours arose +not from any new modifications impress'd upon the Rays of Light by the +Hair, but only from the various inflexions whereby the several Sorts of +Rays were separated from one another, which before separation, by the +mixture of all their Colours, composed the white beam of the Sun's +Light, but whenever separated compose Lights of the several Colours +which they are originally disposed to exhibit. In this 11th Observation, +where the Colours are separated before the Light passes by the Hair, the +least refrangible Rays, which when separated from the rest make red, +were inflected at a greater distance from the Hair, so as to make three +red Fringes at a greater distance from the middle of the Shadow of the +Hair; and the most refrangible Rays which when separated make violet, +were inflected at a less distance from the Hair, so as to make three +violet Fringes at a less distance from the middle of the Shadow of the +Hair. And other Rays of intermediate degrees of Refrangibility were +inflected at intermediate distances from the Hair, so as to make Fringes +of intermediate Colours at intermediate distances from the middle of the +Shadow of the Hair. And in the second Observation, where all the Colours +are mix'd in the white Light which passes by the Hair, these Colours are +separated by the various inflexions of the Rays, and the Fringes which +they make appear all together, and the innermost Fringes being +contiguous make one broad Fringe composed of all the Colours in due +order, the violet lying on the inside of the Fringe next the Shadow, the +red on the outside farthest from the Shadow, and the blue, green, and +yellow, in the middle. And, in like manner, the middlemost Fringes of +all the Colours lying in order, and being contiguous, make another broad +Fringe composed of all the Colours; and the outmost Fringes of all the +Colours lying in order, and being contiguous, make a third broad Fringe +composed of all the Colours. These are the three Fringes of colour'd +Light with which the Shadows of all Bodies are border'd in the second +Observation. + +When I made the foregoing Observations, I design'd to repeat most of +them with more care and exactness, and to make some new ones for +determining the manner how the Rays of Light are bent in their passage +by Bodies, for making the Fringes of Colours with the dark lines between +them. But I was then interrupted, and cannot now think of taking these +things into farther Consideration. And since I have not finish'd this +part of my Design, I shall conclude with proposing only some Queries, in +order to a farther search to be made by others. + +_Query_ 1. Do not Bodies act upon Light at a distance, and by their +action bend its Rays; and is not this action (_cæteris paribus_) +strongest at the least distance? + +_Qu._ 2. Do not the Rays which differ in Refrangibility differ also in +Flexibity; and are they not by their different Inflexions separated from +one another, so as after separation to make the Colours in the three +Fringes above described? And after what manner are they inflected to +make those Fringes? + +_Qu._ 3. Are not the Rays of Light in passing by the edges and sides of +Bodies, bent several times backwards and forwards, with a motion like +that of an Eel? And do not the three Fringes of colour'd Light +above-mention'd arise from three such bendings? + +_Qu._ 4. Do not the Rays of Light which fall upon Bodies, and are +reflected or refracted, begin to bend before they arrive at the Bodies; +and are they not reflected, refracted, and inflected, by one and the +same Principle, acting variously in various Circumstances? + +_Qu._ 5. Do not Bodies and Light act mutually upon one another; that is +to say, Bodies upon Light in emitting, reflecting, refracting and +inflecting it, and Light upon Bodies for heating them, and putting their +parts into a vibrating motion wherein heat consists? + +_Qu._ 6. Do not black Bodies conceive heat more easily from Light than +those of other Colours do, by reason that the Light falling on them is +not reflected outwards, but enters the Bodies, and is often reflected +and refracted within them, until it be stifled and lost? + +_Qu._ 7. Is not the strength and vigor of the action between Light and +sulphureous Bodies observed above, one reason why sulphureous Bodies +take fire more readily, and burn more vehemently than other Bodies do? + +_Qu._ 8. Do not all fix'd Bodies, when heated beyond a certain degree, +emit Light and shine; and is not this Emission perform'd by the +vibrating motions of their parts? And do not all Bodies which abound +with terrestrial parts, and especially with sulphureous ones, emit Light +as often as those parts are sufficiently agitated; whether that +agitation be made by Heat, or by Friction, or Percussion, or +Putrefaction, or by any vital Motion, or any other Cause? As for +instance; Sea-Water in a raging Storm; Quick-silver agitated in _vacuo_; +the Back of a Cat, or Neck of a Horse, obliquely struck or rubbed in a +dark place; Wood, Flesh and Fish while they putrefy; Vapours arising +from putrefy'd Waters, usually call'd _Ignes Fatui_; Stacks of moist Hay +or Corn growing hot by fermentation; Glow-worms and the Eyes of some +Animals by vital Motions; the vulgar _Phosphorus_ agitated by the +attrition of any Body, or by the acid Particles of the Air; Amber and +some Diamonds by striking, pressing or rubbing them; Scrapings of Steel +struck off with a Flint; Iron hammer'd very nimbly till it become so hot +as to kindle Sulphur thrown upon it; the Axletrees of Chariots taking +fire by the rapid rotation of the Wheels; and some Liquors mix'd with +one another whose Particles come together with an Impetus, as Oil of +Vitriol distilled from its weight of Nitre, and then mix'd with twice +its weight of Oil of Anniseeds. So also a Globe of Glass about 8 or 10 +Inches in diameter, being put into a Frame where it may be swiftly +turn'd round its Axis, will in turning shine where it rubs against the +palm of ones Hand apply'd to it: And if at the same time a piece of +white Paper or white Cloth, or the end of ones Finger be held at the +distance of about a quarter of an Inch or half an Inch from that part of +the Glass where it is most in motion, the electrick Vapour which is +excited by the friction of the Glass against the Hand, will by dashing +against the white Paper, Cloth or Finger, be put into such an agitation +as to emit Light, and make the white Paper, Cloth or Finger, appear +lucid like a Glowworm; and in rushing out of the Glass will sometimes +push against the finger so as to be felt. And the same things have been +found by rubbing a long and large Cylinder or Glass or Amber with a +Paper held in ones hand, and continuing the friction till the Glass grew +warm. + +_Qu._ 9. Is not Fire a Body heated so hot as to emit Light copiously? +For what else is a red hot Iron than Fire? And what else is a burning +Coal than red hot Wood? + +_Qu._ 10. Is not Flame a Vapour, Fume or Exhalation heated red hot, that +is, so hot as to shine? For Bodies do not flame without emitting a +copious Fume, and this Fume burns in the Flame. The _Ignis Fatuus_ is a +Vapour shining without heat, and is there not the same difference +between this Vapour and Flame, as between rotten Wood shining without +heat and burning Coals of Fire? In distilling hot Spirits, if the Head +of the Still be taken off, the Vapour which ascends out of the Still +will take fire at the Flame of a Candle, and turn into Flame, and the +Flame will run along the Vapour from the Candle to the Still. Some +Bodies heated by Motion, or Fermentation, if the heat grow intense, fume +copiously, and if the heat be great enough the Fumes will shine and +become Flame. Metals in fusion do not flame for want of a copious Fume, +except Spelter, which fumes copiously, and thereby flames. All flaming +Bodies, as Oil, Tallow, Wax, Wood, fossil Coals, Pitch, Sulphur, by +flaming waste and vanish into burning Smoke, which Smoke, if the Flame +be put out, is very thick and visible, and sometimes smells strongly, +but in the Flame loses its smell by burning, and according to the nature +of the Smoke the Flame is of several Colours, as that of Sulphur blue, +that of Copper open'd with sublimate green, that of Tallow yellow, that +of Camphire white. Smoke passing through Flame cannot but grow red hot, +and red hot Smoke can have no other appearance than that of Flame. When +Gun-powder takes fire, it goes away into Flaming Smoke. For the Charcoal +and Sulphur easily take fire, and set fire to the Nitre, and the Spirit +of the Nitre being thereby rarified into Vapour, rushes out with +Explosion much after the manner that the Vapour of Water rushes out of +an Æolipile; the Sulphur also being volatile is converted into Vapour, +and augments the Explosion. And the acid Vapour of the Sulphur (namely +that which distils under a Bell into Oil of Sulphur,) entring violently +into the fix'd Body of the Nitre, sets loose the Spirit of the Nitre, +and excites a great Fermentation, whereby the Heat is farther augmented, +and the fix'd Body of the Nitre is also rarified into Fume, and the +Explosion is thereby made more vehement and quick. For if Salt of Tartar +be mix'd with Gun-powder, and that Mixture be warm'd till it takes fire, +the Explosion will be more violent and quick than that of Gun-powder +alone; which cannot proceed from any other cause than the action of the +Vapour of the Gun-powder upon the Salt of Tartar, whereby that Salt is +rarified. The Explosion of Gun-powder arises therefore from the violent +action whereby all the Mixture being quickly and vehemently heated, is +rarified and converted into Fume and Vapour: which Vapour, by the +violence of that action, becoming so hot as to shine, appears in the +form of Flame. + +_Qu._ 11. Do not great Bodies conserve their heat the longest, their +parts heating one another, and may not great dense and fix'd Bodies, +when heated beyond a certain degree, emit Light so copiously, as by the +Emission and Re-action of its Light, and the Reflexions and Refractions +of its Rays within its Pores to grow still hotter, till it comes to a +certain period of heat, such as is that of the Sun? And are not the Sun +and fix'd Stars great Earths vehemently hot, whose heat is conserved by +the greatness of the Bodies, and the mutual Action and Reaction between +them, and the Light which they emit, and whose parts are kept from +fuming away, not only by their fixity, but also by the vast weight and +density of the Atmospheres incumbent upon them; and very strongly +compressing them, and condensing the Vapours and Exhalations which arise +from them? For if Water be made warm in any pellucid Vessel emptied of +Air, that Water in the _Vacuum_ will bubble and boil as vehemently as it +would in the open Air in a Vessel set upon the Fire till it conceives a +much greater heat. For the weight of the incumbent Atmosphere keeps down +the Vapours, and hinders the Water from boiling, until it grow much +hotter than is requisite to make it boil _in vacuo_. Also a mixture of +Tin and Lead being put upon a red hot Iron _in vacuo_ emits a Fume and +Flame, but the same Mixture in the open Air, by reason of the incumbent +Atmosphere, does not so much as emit any Fume which can be perceived by +Sight. In like manner the great weight of the Atmosphere which lies upon +the Globe of the Sun may hinder Bodies there from rising up and going +away from the Sun in the form of Vapours and Fumes, unless by means of a +far greater heat than that which on the Surface of our Earth would very +easily turn them into Vapours and Fumes. And the same great weight may +condense those Vapours and Exhalations as soon as they shall at any time +begin to ascend from the Sun, and make them presently fall back again +into him, and by that action increase his Heat much after the manner +that in our Earth the Air increases the Heat of a culinary Fire. And the +same weight may hinder the Globe of the Sun from being diminish'd, +unless by the Emission of Light, and a very small quantity of Vapours +and Exhalations. + +_Qu._ 12. Do not the Rays of Light in falling upon the bottom of the Eye +excite Vibrations in the _Tunica Retina_? Which Vibrations, being +propagated along the solid Fibres of the optick Nerves into the Brain, +cause the Sense of seeing. For because dense Bodies conserve their Heat +a long time, and the densest Bodies conserve their Heat the longest, the +Vibrations of their parts are of a lasting nature, and therefore may be +propagated along solid Fibres of uniform dense Matter to a great +distance, for conveying into the Brain the impressions made upon all the +Organs of Sense. For that Motion which can continue long in one and the +same part of a Body, can be propagated a long way from one part to +another, supposing the Body homogeneal, so that the Motion may not be +reflected, refracted, interrupted or disorder'd by any unevenness of the +Body. + +_Qu._ 13. Do not several sorts of Rays make Vibrations of several +bignesses, which according to their bignesses excite Sensations of +several Colours, much after the manner that the Vibrations of the Air, +according to their several bignesses excite Sensations of several +Sounds? And particularly do not the most refrangible Rays excite the +shortest Vibrations for making a Sensation of deep violet, the least +refrangible the largest for making a Sensation of deep red, and the +several intermediate sorts of Rays, Vibrations of several intermediate +bignesses to make Sensations of the several intermediate Colours? + +_Qu._ 14. May not the harmony and discord of Colours arise from the +proportions of the Vibrations propagated through the Fibres of the +optick Nerves into the Brain, as the harmony and discord of Sounds arise +from the proportions of the Vibrations of the Air? For some Colours, if +they be view'd together, are agreeable to one another, as those of Gold +and Indigo, and others disagree. + +_Qu._ 15. Are not the Species of Objects seen with both Eyes united +where the optick Nerves meet before they come into the Brain, the Fibres +on the right side of both Nerves uniting there, and after union going +thence into the Brain in the Nerve which is on the right side of the +Head, and the Fibres on the left side of both Nerves uniting in the same +place, and after union going into the Brain in the Nerve which is on the +left side of the Head, and these two Nerves meeting in the Brain in such +a manner that their Fibres make but one entire Species or Picture, half +of which on the right side of the Sensorium comes from the right side of +both Eyes through the right side of both optick Nerves to the place +where the Nerves meet, and from thence on the right side of the Head +into the Brain, and the other half on the left side of the Sensorium +comes in like manner from the left side of both Eyes. For the optick +Nerves of such Animals as look the same way with both Eyes (as of Men, +Dogs, Sheep, Oxen, &c.) meet before they come into the Brain, but the +optick Nerves of such Animals as do not look the same way with both Eyes +(as of Fishes, and of the Chameleon,) do not meet, if I am rightly +inform'd. + +_Qu._ 16. When a Man in the dark presses either corner of his Eye with +his Finger, and turns his Eye away from his Finger, he will see a Circle +of Colours like those in the Feather of a Peacock's Tail. If the Eye and +the Finger remain quiet these Colours vanish in a second Minute of Time, +but if the Finger be moved with a quavering Motion they appear again. Do +not these Colours arise from such Motions excited in the bottom of the +Eye by the Pressure and Motion of the Finger, as, at other times are +excited there by Light for causing Vision? And do not the Motions once +excited continue about a Second of Time before they cease? And when a +Man by a stroke upon his Eye sees a flash of Light, are not the like +Motions excited in the _Retina_ by the stroke? And when a Coal of Fire +moved nimbly in the circumference of a Circle, makes the whole +circumference appear like a Circle of Fire; is it not because the +Motions excited in the bottom of the Eye by the Rays of Light are of a +lasting nature, and continue till the Coal of Fire in going round +returns to its former place? And considering the lastingness of the +Motions excited in the bottom of the Eye by Light, are they not of a +vibrating nature? + +_Qu._ 17. If a stone be thrown into stagnating Water, the Waves excited +thereby continue some time to arise in the place where the Stone fell +into the Water, and are propagated from thence in concentrick Circles +upon the Surface of the Water to great distances. And the Vibrations or +Tremors excited in the Air by percussion, continue a little time to move +from the place of percussion in concentrick Spheres to great distances. +And in like manner, when a Ray of Light falls upon the Surface of any +pellucid Body, and is there refracted or reflected, may not Waves of +Vibrations, or Tremors, be thereby excited in the refracting or +reflecting Medium at the point of Incidence, and continue to arise +there, and to be propagated from thence as long as they continue to +arise and be propagated, when they are excited in the bottom of the Eye +by the Pressure or Motion of the Finger, or by the Light which comes +from the Coal of Fire in the Experiments above-mention'd? and are not +these Vibrations propagated from the point of Incidence to great +distances? And do they not overtake the Rays of Light, and by overtaking +them successively, do they not put them into the Fits of easy Reflexion +and easy Transmission described above? For if the Rays endeavour to +recede from the densest part of the Vibration, they may be alternately +accelerated and retarded by the Vibrations overtaking them. + +_Qu._ 18. If in two large tall cylindrical Vessels of Glass inverted, +two little Thermometers be suspended so as not to touch the Vessels, and +the Air be drawn out of one of these Vessels, and these Vessels thus +prepared be carried out of a cold place into a warm one; the Thermometer +_in vacuo_ will grow warm as much, and almost as soon as the Thermometer +which is not _in vacuo_. And when the Vessels are carried back into the +cold place, the Thermometer _in vacuo_ will grow cold almost as soon as +the other Thermometer. Is not the Heat of the warm Room convey'd through +the _Vacuum_ by the Vibrations of a much subtiler Medium than Air, which +after the Air was drawn out remained in the _Vacuum_? And is not this +Medium the same with that Medium by which Light is refracted and +reflected, and by whose Vibrations Light communicates Heat to Bodies, +and is put into Fits of easy Reflexion and easy Transmission? And do not +the Vibrations of this Medium in hot Bodies contribute to the +intenseness and duration of their Heat? And do not hot Bodies +communicate their Heat to contiguous cold ones, by the Vibrations of +this Medium propagated from them into the cold ones? And is not this +Medium exceedingly more rare and subtile than the Air, and exceedingly +more elastick and active? And doth it not readily pervade all Bodies? +And is it not (by its elastick force) expanded through all the Heavens? + +_Qu._ 19. Doth not the Refraction of Light proceed from the different +density of this Æthereal Medium in different places, the Light receding +always from the denser parts of the Medium? And is not the density +thereof greater in free and open Spaces void of Air and other grosser +Bodies, than within the Pores of Water, Glass, Crystal, Gems, and other +compact Bodies? For when Light passes through Glass or Crystal, and +falling very obliquely upon the farther Surface thereof is totally +reflected, the total Reflexion ought to proceed rather from the density +and vigour of the Medium without and beyond the Glass, than from the +rarity and weakness thereof. + +_Qu._ 20. Doth not this Æthereal Medium in passing out of Water, Glass, +Crystal, and other compact and dense Bodies into empty Spaces, grow +denser and denser by degrees, and by that means refract the Rays of +Light not in a point, but by bending them gradually in curve Lines? And +doth not the gradual condensation of this Medium extend to some distance +from the Bodies, and thereby cause the Inflexions of the Rays of Light, +which pass by the edges of dense Bodies, at some distance from the +Bodies? + +_Qu._ 21. Is not this Medium much rarer within the dense Bodies of the +Sun, Stars, Planets and Comets, than in the empty celestial Spaces +between them? And in passing from them to great distances, doth it not +grow denser and denser perpetually, and thereby cause the gravity of +those great Bodies towards one another, and of their parts towards the +Bodies; every Body endeavouring to go from the denser parts of the +Medium towards the rarer? For if this Medium be rarer within the Sun's +Body than at its Surface, and rarer there than at the hundredth part of +an Inch from its Body, and rarer there than at the fiftieth part of an +Inch from its Body, and rarer there than at the Orb of _Saturn_; I see +no reason why the Increase of density should stop any where, and not +rather be continued through all distances from the Sun to _Saturn_, and +beyond. And though this Increase of density may at great distances be +exceeding slow, yet if the elastick force of this Medium be exceeding +great, it may suffice to impel Bodies from the denser parts of the +Medium towards the rarer, with all that power which we call Gravity. And +that the elastick force of this Medium is exceeding great, may be +gather'd from the swiftness of its Vibrations. Sounds move about 1140 +_English_ Feet in a second Minute of Time, and in seven or eight Minutes +of Time they move about one hundred _English_ Miles. Light moves from +the Sun to us in about seven or eight Minutes of Time, which distance is +about 70,000,000 _English_ Miles, supposing the horizontal Parallax of +the Sun to be about 12´´. And the Vibrations or Pulses of this Medium, +that they may cause the alternate Fits of easy Transmission and easy +Reflexion, must be swifter than Light, and by consequence above 700,000 +times swifter than Sounds. And therefore the elastick force of this +Medium, in proportion to its density, must be above 700000 x 700000 +(that is, above 490,000,000,000) times greater than the elastick force +of the Air is in proportion to its density. For the Velocities of the +Pulses of elastick Mediums are in a subduplicate _Ratio_ of the +Elasticities and the Rarities of the Mediums taken together. + +As Attraction is stronger in small Magnets than in great ones in +proportion to their Bulk, and Gravity is greater in the Surfaces of +small Planets than in those of great ones in proportion to their bulk, +and small Bodies are agitated much more by electric attraction than +great ones; so the smallness of the Rays of Light may contribute very +much to the power of the Agent by which they are refracted. And so if +any one should suppose that _Æther_ (like our Air) may contain Particles +which endeavour to recede from one another (for I do not know what this +_Æther_ is) and that its Particles are exceedingly smaller than those of +Air, or even than those of Light: The exceeding smallness of its +Particles may contribute to the greatness of the force by which those +Particles may recede from one another, and thereby make that Medium +exceedingly more rare and elastick than Air, and by consequence +exceedingly less able to resist the motions of Projectiles, and +exceedingly more able to press upon gross Bodies, by endeavouring to +expand it self. + +_Qu._ 22. May not Planets and Comets, and all gross Bodies, perform +their Motions more freely, and with less resistance in this Æthereal +Medium than in any Fluid, which fills all Space adequately without +leaving any Pores, and by consequence is much denser than Quick-silver +or Gold? And may not its resistance be so small, as to be +inconsiderable? For instance; If this _Æther_ (for so I will call it) +should be supposed 700000 times more elastick than our Air, and above +700000 times more rare; its resistance would be above 600,000,000 times +less than that of Water. And so small a resistance would scarce make any +sensible alteration in the Motions of the Planets in ten thousand +Years. If any one would ask how a Medium can be so rare, let him tell me +how the Air, in the upper parts of the Atmosphere, can be above an +hundred thousand thousand times rarer than Gold. Let him also tell me, +how an electrick Body can by Friction emit an Exhalation so rare and +subtile, and yet so potent, as by its Emission to cause no sensible +Diminution of the weight of the electrick Body, and to be expanded +through a Sphere, whose Diameter is above two Feet, and yet to be able +to agitate and carry up Leaf Copper, or Leaf Gold, at the distance of +above a Foot from the electrick Body? And how the Effluvia of a Magnet +can be so rare and subtile, as to pass through a Plate of Glass without +any Resistance or Diminution of their Force, and yet so potent as to +turn a magnetick Needle beyond the Glass? + +_Qu._ 23. Is not Vision perform'd chiefly by the Vibrations of this +Medium, excited in the bottom of the Eye by the Rays of Light, and +propagated through the solid, pellucid and uniform Capillamenta of the +optick Nerves into the place of Sensation? And is not Hearing perform'd +by the Vibrations either of this or some other Medium, excited in the +auditory Nerves by the Tremors of the Air, and propagated through the +solid, pellucid and uniform Capillamenta of those Nerves into the place +of Sensation? And so of the other Senses. + +_Qu._ 24. Is not Animal Motion perform'd by the Vibrations of this +Medium, excited in the Brain by the power of the Will, and propagated +from thence through the solid, pellucid and uniform Capillamenta of the +Nerves into the Muscles, for contracting and dilating them? I suppose +that the Capillamenta of the Nerves are each of them solid and uniform, +that the vibrating Motion of the Æthereal Medium may be propagated along +them from one end to the other uniformly, and without interruption: For +Obstructions in the Nerves create Palsies. And that they may be +sufficiently uniform, I suppose them to be pellucid when view'd singly, +tho' the Reflexions in their cylindrical Surfaces may make the whole +Nerve (composed of many Capillamenta) appear opake and white. For +opacity arises from reflecting Surfaces, such as may disturb and +interrupt the Motions of this Medium. + +[Sidenote: _See the following Scheme, p. 356._] + +_Qu._ 25. Are there not other original Properties of the Rays of Light, +besides those already described? An instance of another original +Property we have in the Refraction of Island Crystal, described first by +_Erasmus Bartholine_, and afterwards more exactly by _Hugenius_, in his +Book _De la Lumiere_. This Crystal is a pellucid fissile Stone, clear as +Water or Crystal of the Rock, and without Colour; enduring a red Heat +without losing its transparency, and in a very strong Heat calcining +without Fusion. Steep'd a Day or two in Water, it loses its natural +Polish. Being rubb'd on Cloth, it attracts pieces of Straws and other +light things, like Ambar or Glass; and with _Aqua fortis_ it makes an +Ebullition. It seems to be a sort of Talk, and is found in form of an +oblique Parallelopiped, with six parallelogram Sides and eight solid +Angles. The obtuse Angles of the Parallelograms are each of them 101 +Degrees and 52 Minutes; the acute ones 78 Degrees and 8 Minutes. Two of +the solid Angles opposite to one another, as C and E, are compassed each +of them with three of these obtuse Angles, and each of the other six +with one obtuse and two acute ones. It cleaves easily in planes parallel +to any of its Sides, and not in any other Planes. It cleaves with a +glossy polite Surface not perfectly plane, but with some little +unevenness. It is easily scratch'd, and by reason of its softness it +takes a Polish very difficultly. It polishes better upon polish'd +Looking-glass than upon Metal, and perhaps better upon Pitch, Leather or +Parchment. Afterwards it must be rubb'd with a little Oil or white of an +Egg, to fill up its Scratches; whereby it will become very transparent +and polite. But for several Experiments, it is not necessary to polish +it. If a piece of this crystalline Stone be laid upon a Book, every +Letter of the Book seen through it will appear double, by means of a +double Refraction. And if any beam of Light falls either +perpendicularly, or in any oblique Angle upon any Surface of this +Crystal, it becomes divided into two beams by means of the same double +Refraction. Which beams are of the same Colour with the incident beam of +Light, and seem equal to one another in the quantity of their Light, or +very nearly equal. One of these Refractions is perform'd by the usual +Rule of Opticks, the Sine of Incidence out of Air into this Crystal +being to the Sine of Refraction, as five to three. The other +Refraction, which may be called the unusual Refraction, is perform'd by +the following Rule. + +[Illustration: FIG. 4.] + +Let ADBC represent the refracting Surface of the Crystal, C the biggest +solid Angle at that Surface, GEHF the opposite Surface, and CK a +perpendicular on that Surface. This perpendicular makes with the edge of +the Crystal CF, an Angle of 19 Degr. 3'. Join KF, and in it take KL, so +that the Angle KCL be 6 Degr. 40'. and the Angle LCF 12 Degr. 23'. And +if ST represent any beam of Light incident at T in any Angle upon the +refracting Surface ADBC, let TV be the refracted beam determin'd by the +given Portion of the Sines 5 to 3, according to the usual Rule of +Opticks. Draw VX parallel and equal to KL. Draw it the same way from V +in which L lieth from K; and joining TX, this line TX shall be the other +refracted beam carried from T to X, by the unusual Refraction. + +If therefore the incident beam ST be perpendicular to the refracting +Surface, the two beams TV and TX, into which it shall become divided, +shall be parallel to the lines CK and CL; one of those beams going +through the Crystal perpendicularly, as it ought to do by the usual Laws +of Opticks, and the other TX by an unusual Refraction diverging from the +perpendicular, and making with it an Angle VTX of about 6-2/3 Degrees, +as is found by Experience. And hence, the Plane VTX, and such like +Planes which are parallel to the Plane CFK, may be called the Planes of +perpendicular Refraction. And the Coast towards which the lines KL and +VX are drawn, may be call'd the Coast of unusual Refraction. + +In like manner Crystal of the Rock has a double Refraction: But the +difference of the two Refractions is not so great and manifest as in +Island Crystal. + +When the beam ST incident on Island Crystal is divided into two beams TV +and TX, and these two beams arrive at the farther Surface of the Glass; +the beam TV, which was refracted at the first Surface after the usual +manner, shall be again refracted entirely after the usual manner at the +second Surface; and the beam TX, which was refracted after the unusual +manner in the first Surface, shall be again refracted entirely after the +unusual manner in the second Surface; so that both these beams shall +emerge out of the second Surface in lines parallel to the first incident +beam ST. + +And if two pieces of Island Crystal be placed one after another, in such +manner that all the Surfaces of the latter be parallel to all the +corresponding Surfaces of the former: The Rays which are refracted after +the usual manner in the first Surface of the first Crystal, shall be +refracted after the usual manner in all the following Surfaces; and the +Rays which are refracted after the unusual manner in the first Surface, +shall be refracted after the unusual manner in all the following +Surfaces. And the same thing happens, though the Surfaces of the +Crystals be any ways inclined to one another, provided that their Planes +of perpendicular Refraction be parallel to one another. + +And therefore there is an original difference in the Rays of Light, by +means of which some Rays are in this Experiment constantly refracted +after the usual manner, and others constantly after the unusual manner: +For if the difference be not original, but arises from new Modifications +impress'd on the Rays at their first Refraction, it would be alter'd by +new Modifications in the three following Refractions; whereas it suffers +no alteration, but is constant, and has the same effect upon the Rays in +all the Refractions. The unusual Refraction is therefore perform'd by an +original property of the Rays. And it remains to be enquired, whether +the Rays have not more original Properties than are yet discover'd. + +_Qu._ 26. Have not the Rays of Light several sides, endued with several +original Properties? For if the Planes of perpendicular Refraction of +the second Crystal be at right Angles with the Planes of perpendicular +Refraction of the first Crystal, the Rays which are refracted after the +usual manner in passing through the first Crystal, will be all of them +refracted after the unusual manner in passing through the second +Crystal; and the Rays which are refracted after the unusual manner in +passing through the first Crystal, will be all of them refracted after +the usual manner in passing through the second Crystal. And therefore +there are not two sorts of Rays differing in their nature from one +another, one of which is constantly and in all Positions refracted after +the usual manner, and the other constantly and in all Positions after +the unusual manner. The difference between the two sorts of Rays in the +Experiment mention'd in the 25th Question, was only in the Positions of +the Sides of the Rays to the Planes of perpendicular Refraction. For one +and the same Ray is here refracted sometimes after the usual, and +sometimes after the unusual manner, according to the Position which its +Sides have to the Crystals. If the Sides of the Ray are posited the same +way to both Crystals, it is refracted after the same manner in them +both: But if that side of the Ray which looks towards the Coast of the +unusual Refraction of the first Crystal, be 90 Degrees from that side of +the same Ray which looks toward the Coast of the unusual Refraction of +the second Crystal, (which may be effected by varying the Position of +the second Crystal to the first, and by consequence to the Rays of +Light,) the Ray shall be refracted after several manners in the several +Crystals. There is nothing more required to determine whether the Rays +of Light which fall upon the second Crystal shall be refracted after +the usual or after the unusual manner, but to turn about this Crystal, +so that the Coast of this Crystal's unusual Refraction may be on this or +on that side of the Ray. And therefore every Ray may be consider'd as +having four Sides or Quarters, two of which opposite to one another +incline the Ray to be refracted after the unusual manner, as often as +either of them are turn'd towards the Coast of unusual Refraction; and +the other two, whenever either of them are turn'd towards the Coast of +unusual Refraction, do not incline it to be otherwise refracted than +after the usual manner. The two first may therefore be call'd the Sides +of unusual Refraction. And since these Dispositions were in the Rays +before their Incidence on the second, third, and fourth Surfaces of the +two Crystals, and suffered no alteration (so far as appears,) by the +Refraction of the Rays in their passage through those Surfaces, and the +Rays were refracted by the same Laws in all the four Surfaces; it +appears that those Dispositions were in the Rays originally, and +suffer'd no alteration by the first Refraction, and that by means of +those Dispositions the Rays were refracted at their Incidence on the +first Surface of the first Crystal, some of them after the usual, and +some of them after the unusual manner, accordingly as their Sides of +unusual Refraction were then turn'd towards the Coast of the unusual +Refraction of that Crystal, or sideways from it. + +Every Ray of Light has therefore two opposite Sides, originally endued +with a Property on which the unusual Refraction depends, and the other +two opposite Sides not endued with that Property. And it remains to be +enquired, whether there are not more Properties of Light by which the +Sides of the Rays differ, and are distinguished from one another. + +In explaining the difference of the Sides of the Rays above mention'd, I +have supposed that the Rays fall perpendicularly on the first Crystal. +But if they fall obliquely on it, the Success is the same. Those Rays +which are refracted after the usual manner in the first Crystal, will be +refracted after the unusual manner in the second Crystal, supposing the +Planes of perpendicular Refraction to be at right Angles with one +another, as above; and on the contrary. + +If the Planes of the perpendicular Refraction of the two Crystals be +neither parallel nor perpendicular to one another, but contain an acute +Angle: The two beams of Light which emerge out of the first Crystal, +will be each of them divided into two more at their Incidence on the +second Crystal. For in this case the Rays in each of the two beams will +some of them have their Sides of unusual Refraction, and some of them +their other Sides turn'd towards the Coast of the unusual Refraction of +the second Crystal. + +_Qu._ 27. Are not all Hypotheses erroneous which have hitherto been +invented for explaining the Phænomena of Light, by new Modifications of +the Rays? For those Phænomena depend not upon new Modifications, as has +been supposed, but upon the original and unchangeable Properties of the +Rays. + +_Qu._ 28. Are not all Hypotheses erroneous, in which Light is supposed +to consist in Pression or Motion, propagated through a fluid Medium? For +in all these Hypotheses the Phænomena of Light have been hitherto +explain'd by supposing that they arise from new Modifications of the +Rays; which is an erroneous Supposition. + +If Light consisted only in Pression propagated without actual Motion, it +would not be able to agitate and heat the Bodies which refract and +reflect it. If it consisted in Motion propagated to all distances in an +instant, it would require an infinite force every moment, in every +shining Particle, to generate that Motion. And if it consisted in +Pression or Motion, propagated either in an instant or in time, it would +bend into the Shadow. For Pression or Motion cannot be propagated in a +Fluid in right Lines, beyond an Obstacle which stops part of the Motion, +but will bend and spread every way into the quiescent Medium which lies +beyond the Obstacle. Gravity tends downwards, but the Pressure of Water +arising from Gravity tends every way with equal Force, and is propagated +as readily, and with as much force sideways as downwards, and through +crooked passages as through strait ones. The Waves on the Surface of +stagnating Water, passing by the sides of a broad Obstacle which stops +part of them, bend afterwards and dilate themselves gradually into the +quiet Water behind the Obstacle. The Waves, Pulses or Vibrations of the +Air, wherein Sounds consist, bend manifestly, though not so much as the +Waves of Water. For a Bell or a Cannon may be heard beyond a Hill which +intercepts the sight of the sounding Body, and Sounds are propagated as +readily through crooked Pipes as through streight ones. But Light is +never known to follow crooked Passages nor to bend into the Shadow. For +the fix'd Stars by the Interposition of any of the Planets cease to be +seen. And so do the Parts of the Sun by the Interposition of the Moon, +_Mercury_ or _Venus_. The Rays which pass very near to the edges of any +Body, are bent a little by the action of the Body, as we shew'd above; +but this bending is not towards but from the Shadow, and is perform'd +only in the passage of the Ray by the Body, and at a very small distance +from it. So soon as the Ray is past the Body, it goes right on. + +[Sidenote: _Mais pour dire comment cela se fait, je n'ay rien trove +jusqu' ici qui me satisfasse._ C. H. de la lumiere, c. 5, p. 91.] + +To explain the unusual Refraction of Island Crystal by Pression or +Motion propagated, has not hitherto been attempted (to my knowledge) +except by _Huygens_, who for that end supposed two several vibrating +Mediums within that Crystal. But when he tried the Refractions in two +successive pieces of that Crystal, and found them such as is mention'd +above; he confessed himself at a loss for explaining them. For Pressions +or Motions, propagated from a shining Body through an uniform Medium, +must be on all sides alike; whereas by those Experiments it appears, +that the Rays of Light have different Properties in their different +Sides. He suspected that the Pulses of _Æther_ in passing through the +first Crystal might receive certain new Modifications, which might +determine them to be propagated in this or that Medium within the +second Crystal, according to the Position of that Crystal. But what +Modifications those might be he could not say, nor think of any thing +satisfactory in that Point. And if he had known that the unusual +Refraction depends not on new Modifications, but on the original and +unchangeable Dispositions of the Rays, he would have found it as +difficult to explain how those Dispositions which he supposed to be +impress'd on the Rays by the first Crystal, could be in them before +their Incidence on that Crystal, and in general, how all Rays emitted by +shining Bodies, can have those Dispositions in them from the beginning. +To me, at least, this seems inexplicable, if Light be nothing else than +Pression or Motion propagated through _Æther_. + +And it is as difficult to explain by these Hypotheses, how Rays can be +alternately in Fits of easy Reflexion and easy Transmission; unless +perhaps one might suppose that there are in all Space two Æthereal +vibrating Mediums, and that the Vibrations of one of them constitute +Light, and the Vibrations of the other are swifter, and as often as they +overtake the Vibrations of the first, put them into those Fits. But how +two _Æthers_ can be diffused through all Space, one of which acts upon +the other, and by consequence is re-acted upon, without retarding, +shattering, dispersing and confounding one anothers Motions, is +inconceivable. And against filling the Heavens with fluid Mediums, +unless they be exceeding rare, a great Objection arises from the regular +and very lasting Motions of the Planets and Comets in all manner of +Courses through the Heavens. For thence it is manifest, that the Heavens +are void of all sensible Resistance, and by consequence of all sensible +Matter. + +For the resisting Power of fluid Mediums arises partly from the +Attrition of the Parts of the Medium, and partly from the _Vis inertiæ_ +of the Matter. That part of the Resistance of a spherical Body which +arises from the Attrition of the Parts of the Medium is very nearly as +the Diameter, or, at the most, as the _Factum_ of the Diameter, and the +Velocity of the spherical Body together. And that part of the Resistance +which arises from the _Vis inertiæ_ of the Matter, is as the Square of +that _Factum_. And by this difference the two sorts of Resistance may be +distinguish'd from one another in any Medium; and these being +distinguish'd, it will be found that almost all the Resistance of Bodies +of a competent Magnitude moving in Air, Water, Quick-silver, and such +like Fluids with a competent Velocity, arises from the _Vis inertiæ_ of +the Parts of the Fluid. + +Now that part of the resisting Power of any Medium which arises from the +Tenacity, Friction or Attrition of the Parts of the Medium, may be +diminish'd by dividing the Matter into smaller Parts, and making the +Parts more smooth and slippery: But that part of the Resistance which +arises from the _Vis inertiæ_, is proportional to the Density of the +Matter, and cannot be diminish'd by dividing the Matter into smaller +Parts, nor by any other means than by decreasing the Density of the +Medium. And for these Reasons the Density of fluid Mediums is very +nearly proportional to their Resistance. Liquors which differ not much +in Density, as Water, Spirit of Wine, Spirit of Turpentine, hot Oil, +differ not much in Resistance. Water is thirteen or fourteen times +lighter than Quick-silver and by consequence thirteen or fourteen times +rarer, and its Resistance is less than that of Quick-silver in the same +Proportion, or thereabouts, as I have found by Experiments made with +Pendulums. The open Air in which we breathe is eight or nine hundred +times lighter than Water, and by consequence eight or nine hundred times +rarer, and accordingly its Resistance is less than that of Water in the +same Proportion, or thereabouts; as I have also found by Experiments +made with Pendulums. And in thinner Air the Resistance is still less, +and at length, by ratifying the Air, becomes insensible. For small +Feathers falling in the open Air meet with great Resistance, but in a +tall Glass well emptied of Air, they fall as fast as Lead or Gold, as I +have seen tried several times. Whence the Resistance seems still to +decrease in proportion to the Density of the Fluid. For I do not find by +any Experiments, that Bodies moving in Quick-silver, Water or Air, meet +with any other sensible Resistance than what arises from the Density and +Tenacity of those sensible Fluids, as they would do if the Pores of +those Fluids, and all other Spaces, were filled with a dense and +subtile Fluid. Now if the Resistance in a Vessel well emptied of Air, +was but an hundred times less than in the open Air, it would be about a +million of times less than in Quick-silver. But it seems to be much less +in such a Vessel, and still much less in the Heavens, at the height of +three or four hundred Miles from the Earth, or above. For Mr. _Boyle_ +has shew'd that Air may be rarified above ten thousand times in Vessels +of Glass; and the Heavens are much emptier of Air than any _Vacuum_ we +can make below. For since the Air is compress'd by the Weight of the +incumbent Atmosphere, and the Density of Air is proportional to the +Force compressing it, it follows by Computation, that at the height of +about seven and a half _English_ Miles from the Earth, the Air is four +times rarer than at the Surface of the Earth; and at the height of 15 +Miles it is sixteen times rarer than that at the Surface of the Earth; +and at the height of 22-1/2, 30, or 38 Miles, it is respectively 64, +256, or 1024 times rarer, or thereabouts; and at the height of 76, 152, +228 Miles, it is about 1000000, 1000000000000, or 1000000000000000000 +times rarer; and so on. + +Heat promotes Fluidity very much by diminishing the Tenacity of Bodies. +It makes many Bodies fluid which are not fluid in cold, and increases +the Fluidity of tenacious Liquids, as of Oil, Balsam, and Honey, and +thereby decreases their Resistance. But it decreases not the Resistance +of Water considerably, as it would do if any considerable part of the +Resistance of Water arose from the Attrition or Tenacity of its Parts. +And therefore the Resistance of Water arises principally and almost +entirely from the _Vis inertiæ_ of its Matter; and by consequence, if +the Heavens were as dense as Water, they would not have much less +Resistance than Water; if as dense as Quick-silver, they would not have +much less Resistance than Quick-silver; if absolutely dense, or full of +Matter without any _Vacuum_, let the Matter be never so subtil and +fluid, they would have a greater Resistance than Quick-silver. A solid +Globe in such a Medium would lose above half its Motion in moving three +times the length of its Diameter, and a Globe not solid (such as are the +Planets,) would be retarded sooner. And therefore to make way for the +regular and lasting Motions of the Planets and Comets, it's necessary to +empty the Heavens of all Matter, except perhaps some very thin Vapours, +Steams, or Effluvia, arising from the Atmospheres of the Earth, Planets, +and Comets, and from such an exceedingly rare Æthereal Medium as we +described above. A dense Fluid can be of no use for explaining the +Phænomena of Nature, the Motions of the Planets and Comets being better +explain'd without it. It serves only to disturb and retard the Motions +of those great Bodies, and make the Frame of Nature languish: And in the +Pores of Bodies, it serves only to stop the vibrating Motions of their +Parts, wherein their Heat and Activity consists. And as it is of no use, +and hinders the Operations of Nature, and makes her languish, so there +is no evidence for its Existence, and therefore it ought to be rejected. +And if it be rejected, the Hypotheses that Light consists in Pression +or Motion, propagated through such a Medium, are rejected with it. + +And for rejecting such a Medium, we have the Authority of those the +oldest and most celebrated Philosophers of _Greece_ and _Phoenicia_, +who made a _Vacuum_, and Atoms, and the Gravity of Atoms, the first +Principles of their Philosophy; tacitly attributing Gravity to some +other Cause than dense Matter. Later Philosophers banish the +Consideration of such a Cause out of natural Philosophy, feigning +Hypotheses for explaining all things mechanically, and referring other +Causes to Metaphysicks: Whereas the main Business of natural Philosophy +is to argue from Phænomena without feigning Hypotheses, and to deduce +Causes from Effects, till we come to the very first Cause, which +certainly is not mechanical; and not only to unfold the Mechanism of the +World, but chiefly to resolve these and such like Questions. What is +there in places almost empty of Matter, and whence is it that the Sun +and Planets gravitate towards one another, without dense Matter between +them? Whence is it that Nature doth nothing in vain; and whence arises +all that Order and Beauty which we see in the World? To what end are +Comets, and whence is it that Planets move all one and the same way in +Orbs concentrick, while Comets move all manner of ways in Orbs very +excentrick; and what hinders the fix'd Stars from falling upon one +another? How came the Bodies of Animals to be contrived with so much +Art, and for what ends were their several Parts? Was the Eye contrived +without Skill in Opticks, and the Ear without Knowledge of Sounds? How +do the Motions of the Body follow from the Will, and whence is the +Instinct in Animals? Is not the Sensory of Animals that place to which +the sensitive Substance is present, and into which the sensible Species +of Things are carried through the Nerves and Brain, that there they may +be perceived by their immediate presence to that Substance? And these +things being rightly dispatch'd, does it not appear from Phænomena that +there is a Being incorporeal, living, intelligent, omnipresent, who in +infinite Space, as it were in his Sensory, sees the things themselves +intimately, and throughly perceives them, and comprehends them wholly by +their immediate presence to himself: Of which things the Images only +carried through the Organs of Sense into our little Sensoriums, are +there seen and beheld by that which in us perceives and thinks. And +though every true Step made in this Philosophy brings us not immediately +to the Knowledge of the first Cause, yet it brings us nearer to it, and +on that account is to be highly valued. + +_Qu._ 29. Are not the Rays of Light very small Bodies emitted from +shining Substances? For such Bodies will pass through uniform Mediums in +right Lines without bending into the Shadow, which is the Nature of the +Rays of Light. They will also be capable of several Properties, and be +able to conserve their Properties unchanged in passing through several +Mediums, which is another Condition of the Rays of Light. Pellucid +Substances act upon the Rays of Light at a distance in refracting, +reflecting, and inflecting them, and the Rays mutually agitate the Parts +of those Substances at a distance for heating them; and this Action and +Re-action at a distance very much resembles an attractive Force between +Bodies. If Refraction be perform'd by Attraction of the Rays, the Sines +of Incidence must be to the Sines of Refraction in a given Proportion, +as we shew'd in our Principles of Philosophy: And this Rule is true by +Experience. The Rays of Light in going out of Glass into a _Vacuum_, are +bent towards the Glass; and if they fall too obliquely on the _Vacuum_, +they are bent backwards into the Glass, and totally reflected; and this +Reflexion cannot be ascribed to the Resistance of an absolute _Vacuum_, +but must be caused by the Power of the Glass attracting the Rays at +their going out of it into the _Vacuum_, and bringing them back. For if +the farther Surface of the Glass be moisten'd with Water or clear Oil, +or liquid and clear Honey, the Rays which would otherwise be reflected +will go into the Water, Oil, or Honey; and therefore are not reflected +before they arrive at the farther Surface of the Glass, and begin to go +out of it. If they go out of it into the Water, Oil, or Honey, they go +on, because the Attraction of the Glass is almost balanced and rendered +ineffectual by the contrary Attraction of the Liquor. But if they go out +of it into a _Vacuum_ which has no Attraction to balance that of the +Glass, the Attraction of the Glass either bends and refracts them, or +brings them back and reflects them. And this is still more evident by +laying together two Prisms of Glass, or two Object-glasses of very long +Telescopes, the one plane, the other a little convex, and so compressing +them that they do not fully touch, nor are too far asunder. For the +Light which falls upon the farther Surface of the first Glass where the +Interval between the Glasses is not above the ten hundred thousandth +Part of an Inch, will go through that Surface, and through the Air or +_Vacuum_ between the Glasses, and enter into the second Glass, as was +explain'd in the first, fourth, and eighth Observations of the first +Part of the second Book. But, if the second Glass be taken away, the +Light which goes out of the second Surface of the first Glass into the +Air or _Vacuum_, will not go on forwards, but turns back into the first +Glass, and is reflected; and therefore it is drawn back by the Power of +the first Glass, there being nothing else to turn it back. Nothing more +is requisite for producing all the variety of Colours, and degrees of +Refrangibility, than that the Rays of Light be Bodies of different +Sizes, the least of which may take violet the weakest and darkest of the +Colours, and be more easily diverted by refracting Surfaces from the +right Course; and the rest as they are bigger and bigger, may make the +stronger and more lucid Colours, blue, green, yellow, and red, and be +more and more difficultly diverted. Nothing more is requisite for +putting the Rays of Light into Fits of easy Reflexion and easy +Transmission, than that they be small Bodies which by their attractive +Powers, or some other Force, stir up Vibrations in what they act upon, +which Vibrations being swifter than the Rays, overtake them +successively, and agitate them so as by turns to increase and decrease +their Velocities, and thereby put them into those Fits. And lastly, the +unusual Refraction of Island-Crystal looks very much as if it were +perform'd by some kind of attractive virtue lodged in certain Sides both +of the Rays, and of the Particles of the Crystal. For were it not for +some kind of Disposition or Virtue lodged in some Sides of the Particles +of the Crystal, and not in their other Sides, and which inclines and +bends the Rays towards the Coast of unusual Refraction, the Rays which +fall perpendicularly on the Crystal, would not be refracted towards that +Coast rather than towards any other Coast, both at their Incidence and +at their Emergence, so as to emerge perpendicularly by a contrary +Situation of the Coast of unusual Refraction at the second Surface; the +Crystal acting upon the Rays after they have pass'd through it, and are +emerging into the Air; or, if you please, into a _Vacuum_. And since the +Crystal by this Disposition or Virtue does not act upon the Rays, unless +when one of their Sides of unusual Refraction looks towards that Coast, +this argues a Virtue or Disposition in those Sides of the Rays, which +answers to, and sympathizes with that Virtue or Disposition of the +Crystal, as the Poles of two Magnets answer to one another. And as +Magnetism may be intended and remitted, and is found only in the Magnet +and in Iron: So this Virtue of refracting the perpendicular Rays is +greater in Island-Crystal, less in Crystal of the Rock, and is not yet +found in other Bodies. I do not say that this Virtue is magnetical: It +seems to be of another kind. I only say, that whatever it be, it's +difficult to conceive how the Rays of Light, unless they be Bodies, can +have a permanent Virtue in two of their Sides which is not in their +other Sides, and this without any regard to their Position to the Space +or Medium through which they pass. + +What I mean in this Question by a _Vacuum_, and by the Attractions of +the Rays of Light towards Glass or Crystal, may be understood by what +was said in the 18th, 19th, and 20th Questions. + +_Quest._ 30. Are not gross Bodies and Light convertible into one +another, and may not Bodies receive much of their Activity from the +Particles of Light which enter their Composition? For all fix'd Bodies +being heated emit Light so long as they continue sufficiently hot, and +Light mutually stops in Bodies as often as its Rays strike upon their +Parts, as we shew'd above. I know no Body less apt to shine than Water; +and yet Water by frequent Distillations changes into fix'd Earth, as Mr. +_Boyle_ has try'd; and then this Earth being enabled to endure a +sufficient Heat, shines by Heat like other Bodies. + +The changing of Bodies into Light, and Light into Bodies, is very +conformable to the Course of Nature, which seems delighted with +Transmutations. Water, which is a very fluid tasteless Salt, she changes +by Heat into Vapour, which is a sort of Air, and by Cold into Ice, which +is a hard, pellucid, brittle, fusible Stone; and this Stone returns into +Water by Heat, and Vapour returns into Water by Cold. Earth by Heat +becomes Fire, and by Cold returns into Earth. Dense Bodies by +Fermentation rarify into several sorts of Air, and this Air by +Fermentation, and sometimes without it, returns into dense Bodies. +Mercury appears sometimes in the form of a fluid Metal, sometimes in the +form of a hard brittle Metal, sometimes in the form of a corrosive +pellucid Salt call'd Sublimate, sometimes in the form of a tasteless, +pellucid, volatile white Earth, call'd _Mercurius Dulcis_; or in that of +a red opake volatile Earth, call'd Cinnaber; or in that of a red or +white Precipitate, or in that of a fluid Salt; and in Distillation it +turns into Vapour, and being agitated _in Vacuo_, it shines like Fire. +And after all these Changes it returns again into its first form of +Mercury. Eggs grow from insensible Magnitudes, and change into Animals; +Tadpoles into Frogs; and Worms into Flies. All Birds, Beasts and Fishes, +Insects, Trees, and other Vegetables, with their several Parts, grow out +of Water and watry Tinctures and Salts, and by Putrefaction return again +into watry Substances. And Water standing a few Days in the open Air, +yields a Tincture, which (like that of Malt) by standing longer yields a +Sediment and a Spirit, but before Putrefaction is fit Nourishment for +Animals and Vegetables. And among such various and strange +Transmutations, why may not Nature change Bodies into Light, and Light +into Bodies? + +_Quest._ 31. Have not the small Particles of Bodies certain Powers, +Virtues, or Forces, by which they act at a distance, not only upon the +Rays of Light for reflecting, refracting, and inflecting them, but also +upon one another for producing a great Part of the Phænomena of Nature? +For it's well known, that Bodies act one upon another by the Attractions +of Gravity, Magnetism, and Electricity; and these Instances shew the +Tenor and Course of Nature, and make it not improbable but that there +may be more attractive Powers than these. For Nature is very consonant +and conformable to her self. How these Attractions may be perform'd, I +do not here consider. What I call Attraction may be perform'd by +impulse, or by some other means unknown to me. I use that Word here to +signify only in general any Force by which Bodies tend towards one +another, whatsoever be the Cause. For we must learn from the Phænomena +of Nature what Bodies attract one another, and what are the Laws and +Properties of the Attraction, before we enquire the Cause by which the +Attraction is perform'd. The Attractions of Gravity, Magnetism, and +Electricity, reach to very sensible distances, and so have been observed +by vulgar Eyes, and there may be others which reach to so small +distances as hitherto escape Observation; and perhaps electrical +Attraction may reach to such small distances, even without being excited +by Friction. + +For when Salt of Tartar runs _per Deliquium_, is not this done by an +Attraction between the Particles of the Salt of Tartar, and the +Particles of the Water which float in the Air in the form of Vapours? +And why does not common Salt, or Salt-petre, or Vitriol, run _per +Deliquium_, but for want of such an Attraction? Or why does not Salt of +Tartar draw more Water out of the Air than in a certain Proportion to +its quantity, but for want of an attractive Force after it is satiated +with Water? And whence is it but from this attractive Power that Water +which alone distils with a gentle luke-warm Heat, will not distil from +Salt of Tartar without a great Heat? And is it not from the like +attractive Power between the Particles of Oil of Vitriol and the +Particles of Water, that Oil of Vitriol draws to it a good quantity of +Water out of the Air, and after it is satiated draws no more, and in +Distillation lets go the Water very difficultly? And when Water and Oil +of Vitriol poured successively into the same Vessel grow very hot in the +mixing, does not this Heat argue a great Motion in the Parts of the +Liquors? And does not this Motion argue, that the Parts of the two +Liquors in mixing coalesce with Violence, and by consequence rush +towards one another with an accelerated Motion? And when _Aqua fortis_, +or Spirit of Vitriol poured upon Filings of Iron dissolves the Filings +with a great Heat and Ebullition, is not this Heat and Ebullition +effected by a violent Motion of the Parts, and does not that Motion +argue that the acid Parts of the Liquor rush towards the Parts of the +Metal with violence, and run forcibly into its Pores till they get +between its outmost Particles, and the main Mass of the Metal, and +surrounding those Particles loosen them from the main Mass, and set them +at liberty to float off into the Water? And when the acid Particles, +which alone would distil with an easy Heat, will not separate from the +Particles of the Metal without a very violent Heat, does not this +confirm the Attraction between them? + +When Spirit of Vitriol poured upon common Salt or Salt-petre makes an +Ebullition with the Salt, and unites with it, and in Distillation the +Spirit of the common Salt or Salt-petre comes over much easier than it +would do before, and the acid part of the Spirit of Vitriol stays +behind; does not this argue that the fix'd Alcaly of the Salt attracts +the acid Spirit of the Vitriol more strongly than its own Spirit, and +not being able to hold them both, lets go its own? And when Oil of +Vitriol is drawn off from its weight of Nitre, and from both the +Ingredients a compound Spirit of Nitre is distilled, and two parts of +this Spirit are poured on one part of Oil of Cloves or Carraway Seeds, +or of any ponderous Oil of vegetable or animal Substances, or Oil of +Turpentine thicken'd with a little Balsam of Sulphur, and the Liquors +grow so very hot in mixing, as presently to send up a burning Flame; +does not this very great and sudden Heat argue that the two Liquors mix +with violence, and that their Parts in mixing run towards one another +with an accelerated Motion, and clash with the greatest Force? And is it +not for the same reason that well rectified Spirit of Wine poured on the +same compound Spirit flashes; and that the _Pulvis fulminans_, composed +of Sulphur, Nitre, and Salt of Tartar, goes off with a more sudden and +violent Explosion than Gun-powder, the acid Spirits of the Sulphur and +Nitre rushing towards one another, and towards the Salt of Tartar, with +so great a violence, as by the shock to turn the whole at once into +Vapour and Flame? Where the Dissolution is slow, it makes a slow +Ebullition and a gentle Heat; and where it is quicker, it makes a +greater Ebullition with more heat; and where it is done at once, the +Ebullition is contracted into a sudden Blast or violent Explosion, with +a heat equal to that of Fire and Flame. So when a Drachm of the +above-mention'd compound Spirit of Nitre was poured upon half a Drachm +of Oil of Carraway Seeds _in vacuo_, the Mixture immediately made a +flash like Gun-powder, and burst the exhausted Receiver, which was a +Glass six Inches wide, and eight Inches deep. And even the gross Body of +Sulphur powder'd, and with an equal weight of Iron Filings and a little +Water made into Paste, acts upon the Iron, and in five or six hours +grows too hot to be touch'd, and emits a Flame. And by these Experiments +compared with the great quantity of Sulphur with which the Earth +abounds, and the warmth of the interior Parts of the Earth, and hot +Springs, and burning Mountains, and with Damps, mineral Coruscations, +Earthquakes, hot suffocating Exhalations, Hurricanes, and Spouts; we may +learn that sulphureous Steams abound in the Bowels of the Earth and +ferment with Minerals, and sometimes take fire with a sudden Coruscation +and Explosion; and if pent up in subterraneous Caverns, burst the +Caverns with a great shaking of the Earth, as in springing of a Mine. +And then the Vapour generated by the Explosion, expiring through the +Pores of the Earth, feels hot and suffocates, and makes Tempests and +Hurricanes, and sometimes causes the Land to slide, or the Sea to boil, +and carries up the Water thereof in Drops, which by their weight fall +down again in Spouts. Also some sulphureous Steams, at all times when +the Earth is dry, ascending into the Air, ferment there with nitrous +Acids, and sometimes taking fire cause Lightning and Thunder, and fiery +Meteors. For the Air abounds with acid Vapours fit to promote +Fermentations, as appears by the rusting of Iron and Copper in it, the +kindling of Fire by blowing, and the beating of the Heart by means of +Respiration. Now the above-mention'd Motions are so great and violent as +to shew that in Fermentations the Particles of Bodies which almost rest, +are put into new Motions by a very potent Principle, which acts upon +them only when they approach one another, and causes them to meet and +clash with great violence, and grow hot with the motion, and dash one +another into pieces, and vanish into Air, and Vapour, and Flame. + +When Salt of Tartar _per deliquium_, being poured into the Solution of +any Metal, precipitates the Metal and makes it fall down to the bottom +of the Liquor in the form of Mud: Does not this argue that the acid +Particles are attracted more strongly by the Salt of Tartar than by the +Metal, and by the stronger Attraction go from the Metal to the Salt of +Tartar? And so when a Solution of Iron in _Aqua fortis_ dissolves the +_Lapis Calaminaris_, and lets go the Iron, or a Solution of Copper +dissolves Iron immersed in it and lets go the Copper, or a Solution of +Silver dissolves Copper and lets go the Silver, or a Solution of Mercury +in _Aqua fortis_ being poured upon Iron, Copper, Tin, or Lead, dissolves +the Metal and lets go the Mercury; does not this argue that the acid +Particles of the _Aqua fortis_ are attracted more strongly by the _Lapis +Calaminaris_ than by Iron, and more strongly by Iron than by Copper, and +more strongly by Copper than by Silver, and more strongly by Iron, +Copper, Tin, and Lead, than by Mercury? And is it not for the same +reason that Iron requires more _Aqua fortis_ to dissolve it than Copper, +and Copper more than the other Metals; and that of all Metals, Iron is +dissolved most easily, and is most apt to rust; and next after Iron, +Copper? + +When Oil of Vitriol is mix'd with a little Water, or is run _per +deliquium_, and in Distillation the Water ascends difficultly, and +brings over with it some part of the Oil of Vitriol in the form of +Spirit of Vitriol, and this Spirit being poured upon Iron, Copper, or +Salt of Tartar, unites with the Body and lets go the Water; doth not +this shew that the acid Spirit is attracted by the Water, and more +attracted by the fix'd Body than by the Water, and therefore lets go the +Water to close with the fix'd Body? And is it not for the same reason +that the Water and acid Spirits which are mix'd together in Vinegar, +_Aqua fortis_, and Spirit of Salt, cohere and rise together in +Distillation; but if the _Menstruum_ be poured on Salt of Tartar, or on +Lead, or Iron, or any fix'd Body which it can dissolve, the Acid by a +stronger Attraction adheres to the Body, and lets go the Water? And is +it not also from a mutual Attraction that the Spirits of Soot and +Sea-Salt unite and compose the Particles of Sal-armoniac, which are less +volatile than before, because grosser and freer from Water; and that the +Particles of Sal-armoniac in Sublimation carry up the Particles of +Antimony, which will not sublime alone; and that the Particles of +Mercury uniting with the acid Particles of Spirit of Salt compose +Mercury sublimate, and with the Particles of Sulphur, compose Cinnaber; +and that the Particles of Spirit of Wine and Spirit of Urine well +rectified unite, and letting go the Water which dissolved them, compose +a consistent Body; and that in subliming Cinnaber from Salt of Tartar, +or from quick Lime, the Sulphur by a stronger Attraction of the Salt or +Lime lets go the Mercury, and stays with the fix'd Body; and that when +Mercury sublimate is sublimed from Antimony, or from Regulus of +Antimony, the Spirit of Salt lets go the Mercury, and unites with the +antimonial metal which attracts it more strongly, and stays with it till +the Heat be great enough to make them both ascend together, and then +carries up the Metal with it in the form of a very fusible Salt, called +Butter of Antimony, although the Spirit of Salt alone be almost as +volatile as Water, and the Antimony alone as fix'd as Lead? + +When _Aqua fortis_ dissolves Silver and not Gold, and _Aqua regia_ +dissolves Gold and not Silver, may it not be said that _Aqua fortis_ is +subtil enough to penetrate Gold as well as Silver, but wants the +attractive Force to give it Entrance; and that _Aqua regia_ is subtil +enough to penetrate Silver as well as Gold, but wants the attractive +Force to give it Entrance? For _Aqua regia_ is nothing else than _Aqua +fortis_ mix'd with some Spirit of Salt, or with Sal-armoniac; and even +common Salt dissolved in _Aqua fortis_, enables the _Menstruum_ to +dissolve Gold, though the Salt be a gross Body. When therefore Spirit of +Salt precipitates Silver out of _Aqua fortis_, is it not done by +attracting and mixing with the _Aqua fortis_, and not attracting, or +perhaps repelling Silver? And when Water precipitates Antimony out of +the Sublimate of Antimony and Sal-armoniac, or out of Butter of +Antimony, is it not done by its dissolving, mixing with, and weakening +the Sal-armoniac or Spirit of Salt, and its not attracting, or perhaps +repelling the Antimony? And is it not for want of an attractive virtue +between the Parts of Water and Oil, of Quick-silver and Antimony, of +Lead and Iron, that these Substances do not mix; and by a weak +Attraction, that Quick-silver and Copper mix difficultly; and from a +strong one, that Quick-silver and Tin, Antimony and Iron, Water and +Salts, mix readily? And in general, is it not from the same Principle +that Heat congregates homogeneal Bodies, and separates heterogeneal +ones? + +When Arsenick with Soap gives a Regulus, and with Mercury sublimate a +volatile fusible Salt, like Butter of Antimony, doth not this shew that +Arsenick, which is a Substance totally volatile, is compounded of fix'd +and volatile Parts, strongly cohering by a mutual Attraction, so that +the volatile will not ascend without carrying up the fixed? And so, when +an equal weight of Spirit of Wine and Oil of Vitriol are digested +together, and in Distillation yield two fragrant and volatile Spirits +which will not mix with one another, and a fix'd black Earth remains +behind; doth not this shew that Oil of Vitriol is composed of volatile +and fix'd Parts strongly united by Attraction, so as to ascend together +in form of a volatile, acid, fluid Salt, until the Spirit of Wine +attracts and separates the volatile Parts from the fixed? And therefore, +since Oil of Sulphur _per Campanam_ is of the same Nature with Oil of +Vitriol, may it not be inferred, that Sulphur is also a mixture of +volatile and fix'd Parts so strongly cohering by Attraction, as to +ascend together in Sublimation. By dissolving Flowers of Sulphur in Oil +of Turpentine, and distilling the Solution, it is found that Sulphur is +composed of an inflamable thick Oil or fat Bitumen, an acid Salt, a very +fix'd Earth, and a little Metal. The three first were found not much +unequal to one another, the fourth in so small a quantity as scarce to +be worth considering. The acid Salt dissolved in Water, is the same with +Oil of Sulphur _per Campanam_, and abounding much in the Bowels of the +Earth, and particularly in Markasites, unites it self to the other +Ingredients of the Markasite, which are, Bitumen, Iron, Copper, and +Earth, and with them compounds Allum, Vitriol, and Sulphur. With the +Earth alone it compounds Allum; with the Metal alone, or Metal and +Earth together, it compounds Vitriol; and with the Bitumen and Earth it +compounds Sulphur. Whence it comes to pass that Markasites abound with +those three Minerals. And is it not from the mutual Attraction of the +Ingredients that they stick together for compounding these Minerals, and +that the Bitumen carries up the other Ingredients of the Sulphur, which +without it would not sublime? And the same Question may be put +concerning all, or almost all the gross Bodies in Nature. For all the +Parts of Animals and Vegetables are composed of Substances volatile and +fix'd, fluid and solid, as appears by their Analysis; and so are Salts +and Minerals, so far as Chymists have been hitherto able to examine +their Composition. + +When Mercury sublimate is re-sublimed with fresh Mercury, and becomes +_Mercurius Dulcis_, which is a white tasteless Earth scarce dissolvable +in Water, and _Mercurius Dulcis_ re-sublimed with Spirit of Salt returns +into Mercury sublimate; and when Metals corroded with a little acid turn +into rust, which is an Earth tasteless and indissolvable in Water, and +this Earth imbibed with more acid becomes a metallick Salt; and when +some Stones, as Spar of Lead, dissolved in proper _Menstruums_ become +Salts; do not these things shew that Salts are dry Earth and watry Acid +united by Attraction, and that the Earth will not become a Salt without +so much acid as makes it dissolvable in Water? Do not the sharp and +pungent Tastes of Acids arise from the strong Attraction whereby the +acid Particles rush upon and agitate the Particles of the Tongue? And +when Metals are dissolved in acid _Menstruums_, and the Acids in +conjunction with the Metal act after a different manner, so that the +Compound has a different Taste much milder than before, and sometimes a +sweet one; is it not because the Acids adhere to the metallick +Particles, and thereby lose much of their Activity? And if the Acid be +in too small a Proportion to make the Compound dissolvable in Water, +will it not by adhering strongly to the Metal become unactive and lose +its Taste, and the Compound be a tasteless Earth? For such things as are +not dissolvable by the Moisture of the Tongue, act not upon the Taste. + +As Gravity makes the Sea flow round the denser and weightier Parts of +the Globe of the Earth, so the Attraction may make the watry Acid flow +round the denser and compacter Particles of Earth for composing the +Particles of Salt. For otherwise the Acid would not do the Office of a +Medium between the Earth and common Water, for making Salts dissolvable +in the Water; nor would Salt of Tartar readily draw off the Acid from +dissolved Metals, nor Metals the Acid from Mercury. Now, as in the great +Globe of the Earth and Sea, the densest Bodies by their Gravity sink +down in Water, and always endeavour to go towards the Center of the +Globe; so in Particles of Salt, the densest Matter may always endeavour +to approach the Center of the Particle: So that a Particle of Salt may +be compared to a Chaos; being dense, hard, dry, and earthy in the +Center; and rare, soft, moist, and watry in the Circumference. And +hence it seems to be that Salts are of a lasting Nature, being scarce +destroy'd, unless by drawing away their watry Parts by violence, or by +letting them soak into the Pores of the central Earth by a gentle Heat +in Putrefaction, until the Earth be dissolved by the Water, and +separated into smaller Particles, which by reason of their Smallness +make the rotten Compound appear of a black Colour. Hence also it may be, +that the Parts of Animals and Vegetables preserve their several Forms, +and assimilate their Nourishment; the soft and moist Nourishment easily +changing its Texture by a gentle Heat and Motion, till it becomes like +the dense, hard, dry, and durable Earth in the Center of each Particle. +But when the Nourishment grows unfit to be assimilated, or the central +Earth grows too feeble to assimilate it, the Motion ends in Confusion, +Putrefaction, and Death. + +If a very small quantity of any Salt or Vitriol be dissolved in a great +quantity of Water, the Particles of the Salt or Vitriol will not sink to +the bottom, though they be heavier in Specie than the Water, but will +evenly diffuse themselves into all the Water, so as to make it as saline +at the top as at the bottom. And does not this imply that the Parts of +the Salt or Vitriol recede from one another, and endeavour to expand +themselves, and get as far asunder as the quantity of Water in which +they float, will allow? And does not this Endeavour imply that they have +a repulsive Force by which they fly from one another, or at least, that +they attract the Water more strongly than they do one another? For as +all things ascend in Water which are less attracted than Water, by the +gravitating Power of the Earth; so all the Particles of Salt which float +in Water, and are less attracted than Water by any one Particle of Salt, +must recede from that Particle, and give way to the more attracted +Water. + +When any saline Liquor is evaporated to a Cuticle and let cool, the Salt +concretes in regular Figures; which argues, that the Particles of the +Salt before they concreted, floated in the Liquor at equal distances in +rank and file, and by consequence that they acted upon one another by +some Power which at equal distances is equal, at unequal distances +unequal. For by such a Power they will range themselves uniformly, and +without it they will float irregularly, and come together as +irregularly. And since the Particles of Island-Crystal act all the same +way upon the Rays of Light for causing the unusual Refraction, may it +not be supposed that in the Formation of this Crystal, the Particles not +only ranged themselves in rank and file for concreting in regular +Figures, but also by some kind of polar Virtue turned their homogeneal +Sides the same way. + +The Parts of all homogeneal hard Bodies which fully touch one another, +stick together very strongly. And for explaining how this may be, some +have invented hooked Atoms, which is begging the Question; and others +tell us that Bodies are glued together by rest, that is, by an occult +Quality, or rather by nothing; and others, that they stick together by +conspiring Motions, that is, by relative rest amongst themselves. I had +rather infer from their Cohesion, that their Particles attract one +another by some Force, which in immediate Contact is exceeding strong, +at small distances performs the chymical Operations above-mention'd, and +reaches not far from the Particles with any sensible Effect. + +All Bodies seem to be composed of hard Particles: For otherwise Fluids +would not congeal; as Water, Oils, Vinegar, and Spirit or Oil of Vitriol +do by freezing; Mercury by Fumes of Lead; Spirit of Nitre and Mercury, +by dissolving the Mercury and evaporating the Flegm; Spirit of Wine and +Spirit of Urine, by deflegming and mixing them; and Spirit of Urine and +Spirit of Salt, by subliming them together to make Sal-armoniac. Even +the Rays of Light seem to be hard Bodies; for otherwise they would not +retain different Properties in their different Sides. And therefore +Hardness may be reckon'd the Property of all uncompounded Matter. At +least, this seems to be as evident as the universal Impenetrability of +Matter. For all Bodies, so far as Experience reaches, are either hard, +or may be harden'd; and we have no other Evidence of universal +Impenetrability, besides a large Experience without an experimental +Exception. Now if compound Bodies are so very hard as we find some of +them to be, and yet are very porous, and consist of Parts which are only +laid together; the simple Particles which are void of Pores, and were +never yet divided, must be much harder. For such hard Particles being +heaped up together, can scarce touch one another in more than a few +Points, and therefore must be separable by much less Force than is +requisite to break a solid Particle, whose Parts touch in all the Space +between them, without any Pores or Interstices to weaken their Cohesion. +And how such very hard Particles which are only laid together and touch +only in a few Points, can stick together, and that so firmly as they do, +without the assistance of something which causes them to be attracted or +press'd towards one another, is very difficult to conceive. + +The same thing I infer also from the cohering of two polish'd Marbles +_in vacuo_, and from the standing of Quick-silver in the Barometer at +the height of 50, 60 or 70 Inches, or above, when ever it is well-purged +of Air and carefully poured in, so that its Parts be every where +contiguous both to one another and to the Glass. The Atmosphere by its +weight presses the Quick-silver into the Glass, to the height of 29 or +30 Inches. And some other Agent raises it higher, not by pressing it +into the Glass, but by making its Parts stick to the Glass, and to one +another. For upon any discontinuation of Parts, made either by Bubbles +or by shaking the Glass, the whole Mercury falls down to the height of +29 or 30 Inches. + +And of the same kind with these Experiments are those that follow. If +two plane polish'd Plates of Glass (suppose two pieces of a polish'd +Looking-glass) be laid together, so that their sides be parallel and at +a very small distance from one another, and then their lower edges be +dipped into Water, the Water will rise up between them. And the less +the distance of the Glasses is, the greater will be the height to which +the Water will rise. If the distance be about the hundredth part of an +Inch, the Water will rise to the height of about an Inch; and if the +distance be greater or less in any Proportion, the height will be +reciprocally proportional to the distance very nearly. For the +attractive Force of the Glasses is the same, whether the distance +between them be greater or less; and the weight of the Water drawn up is +the same, if the height of it be reciprocally proportional to the +distance of the Glasses. And in like manner, Water ascends between two +Marbles polish'd plane, when their polish'd sides are parallel, and at a +very little distance from one another, And if slender Pipes of Glass be +dipped at one end into stagnating Water, the Water will rise up within +the Pipe, and the height to which it rises will be reciprocally +proportional to the Diameter of the Cavity of the Pipe, and will equal +the height to which it rises between two Planes of Glass, if the +Semi-diameter of the Cavity of the Pipe be equal to the distance between +the Planes, or thereabouts. And these Experiments succeed after the same +manner _in vacuo_ as in the open Air, (as hath been tried before the +Royal Society,) and therefore are not influenced by the Weight or +Pressure of the Atmosphere. + +And if a large Pipe of Glass be filled with sifted Ashes well pressed +together in the Glass, and one end of the Pipe be dipped into stagnating +Water, the Water will rise up slowly in the Ashes, so as in the space +of a Week or Fortnight to reach up within the Glass, to the height of 30 +or 40 Inches above the stagnating Water. And the Water rises up to this +height by the Action only of those Particles of the Ashes which are upon +the Surface of the elevated Water; the Particles which are within the +Water, attracting or repelling it as much downwards as upwards. And +therefore the Action of the Particles is very strong. But the Particles +of the Ashes being not so dense and close together as those of Glass, +their Action is not so strong as that of Glass, which keeps Quick-silver +suspended to the height of 60 or 70 Inches, and therefore acts with a +Force which would keep Water suspended to the height of above 60 Feet. + +By the same Principle, a Sponge sucks in Water, and the Glands in the +Bodies of Animals, according to their several Natures and Dispositions, +suck in various Juices from the Blood. + +If two plane polish'd Plates of Glass three or four Inches broad, and +twenty or twenty five long, be laid one of them parallel to the Horizon, +the other upon the first, so as at one of their ends to touch one +another, and contain an Angle of about 10 or 15 Minutes, and the same be +first moisten'd on their inward sides with a clean Cloth dipp'd into Oil +of Oranges or Spirit of Turpentine, and a Drop or two of the Oil or +Spirit be let fall upon the lower Glass at the other; so soon as the +upper Glass is laid down upon the lower, so as to touch it at one end as +above, and to touch the Drop at the other end, making with the lower +Glass an Angle of about 10 or 15 Minutes; the Drop will begin to move +towards the Concourse of the Glasses, and will continue to move with an +accelerated Motion, till it arrives at that Concourse of the Glasses. +For the two Glasses attract the Drop, and make it run that way towards +which the Attractions incline. And if when the Drop is in motion you +lift up that end of the Glasses where they meet, and towards which the +Drop moves, the Drop will ascend between the Glasses, and therefore is +attracted. And as you lift up the Glasses more and more, the Drop will +ascend slower and slower, and at length rest, being then carried +downward by its Weight, as much as upwards by the Attraction. And by +this means you may know the Force by which the Drop is attracted at all +distances from the Concourse of the Glasses. + +Now by some Experiments of this kind, (made by Mr. _Hauksbee_) it has +been found that the Attraction is almost reciprocally in a duplicate +Proportion of the distance of the middle of the Drop from the Concourse +of the Glasses, _viz._ reciprocally in a simple Proportion, by reason of +the spreading of the Drop, and its touching each Glass in a larger +Surface; and again reciprocally in a simple Proportion, by reason of the +Attractions growing stronger within the same quantity of attracting +Surface. The Attraction therefore within the same quantity of attracting +Surface, is reciprocally as the distance between the Glasses. And +therefore where the distance is exceeding small, the Attraction must be +exceeding great. By the Table in the second Part of the second Book, +wherein the thicknesses of colour'd Plates of Water between two Glasses +are set down, the thickness of the Plate where it appears very black, is +three eighths of the ten hundred thousandth part of an Inch. And where +the Oil of Oranges between the Glasses is of this thickness, the +Attraction collected by the foregoing Rule, seems to be so strong, as +within a Circle of an Inch in diameter, to suffice to hold up a Weight +equal to that of a Cylinder of Water of an Inch in diameter, and two or +three Furlongs in length. And where it is of a less thickness the +Attraction may be proportionally greater, and continue to increase, +until the thickness do not exceed that of a single Particle of the Oil. +There are therefore Agents in Nature able to make the Particles of +Bodies stick together by very strong Attractions. And it is the Business +of experimental Philosophy to find them out. + +Now the smallest Particles of Matter may cohere by the strongest +Attractions, and compose bigger Particles of weaker Virtue; and many of +these may cohere and compose bigger Particles whose Virtue is still +weaker, and so on for divers Successions, until the Progression end in +the biggest Particles on which the Operations in Chymistry, and the +Colours of natural Bodies depend, and which by cohering compose Bodies +of a sensible Magnitude. If the Body is compact, and bends or yields +inward to Pression without any sliding of its Parts, it is hard and +elastick, returning to its Figure with a Force rising from the mutual +Attraction of its Parts. If the Parts slide upon one another, the Body +is malleable or soft. If they slip easily, and are of a fit Size to be +agitated by Heat, and the Heat is big enough to keep them in Agitation, +the Body is fluid; and if it be apt to stick to things, it is humid; and +the Drops of every fluid affect a round Figure by the mutual Attraction +of their Parts, as the Globe of the Earth and Sea affects a round Figure +by the mutual Attraction of its Parts by Gravity. + +Since Metals dissolved in Acids attract but a small quantity of the +Acid, their attractive Force can reach but to a small distance from +them. And as in Algebra, where affirmative Quantities vanish and cease, +there negative ones begin; so in Mechanicks, where Attraction ceases, +there a repulsive Virtue ought to succeed. And that there is such a +Virtue, seems to follow from the Reflexions and Inflexions of the Rays +of Light. For the Rays are repelled by Bodies in both these Cases, +without the immediate Contact of the reflecting or inflecting Body. It +seems also to follow from the Emission of Light; the Ray so soon as it +is shaken off from a shining Body by the vibrating Motion of the Parts +of the Body, and gets beyond the reach of Attraction, being driven away +with exceeding great Velocity. For that Force which is sufficient to +turn it back in Reflexion, may be sufficient to emit it. It seems also +to follow from the Production of Air and Vapour. The Particles when they +are shaken off from Bodies by Heat or Fermentation, so soon as they are +beyond the reach of the Attraction of the Body, receding from it, and +also from one another with great Strength, and keeping at a distance, +so as sometimes to take up above a Million of Times more space than they +did before in the form of a dense Body. Which vast Contraction and +Expansion seems unintelligible, by feigning the Particles of Air to be +springy and ramous, or rolled up like Hoops, or by any other means than +a repulsive Power. The Particles of Fluids which do not cohere too +strongly, and are of such a Smallness as renders them most susceptible +of those Agitations which keep Liquors in a Fluor, are most easily +separated and rarified into Vapour, and in the Language of the Chymists, +they are volatile, rarifying with an easy Heat, and condensing with +Cold. But those which are grosser, and so less susceptible of Agitation, +or cohere by a stronger Attraction, are not separated without a stronger +Heat, or perhaps not without Fermentation. And these last are the Bodies +which Chymists call fix'd, and being rarified by Fermentation, become +true permanent Air; those Particles receding from one another with the +greatest Force, and being most difficultly brought together, which upon +Contact cohere most strongly. And because the Particles of permanent Air +are grosser, and arise from denser Substances than those of Vapours, +thence it is that true Air is more ponderous than Vapour, and that a +moist Atmosphere is lighter than a dry one, quantity for quantity. From +the same repelling Power it seems to be that Flies walk upon the Water +without wetting their Feet; and that the Object-glasses of long +Telescopes lie upon one another without touching; and that dry Powders +are difficultly made to touch one another so as to stick together, +unless by melting them, or wetting them with Water, which by exhaling +may bring them together; and that two polish'd Marbles, which by +immediate Contact stick together, are difficultly brought so close +together as to stick. + +And thus Nature will be very conformable to her self and very simple, +performing all the great Motions of the heavenly Bodies by the +Attraction of Gravity which intercedes those Bodies, and almost all the +small ones of their Particles by some other attractive and repelling +Powers which intercede the Particles. The _Vis inertiæ_ is a passive +Principle by which Bodies persist in their Motion or Rest, receive +Motion in proportion to the Force impressing it, and resist as much as +they are resisted. By this Principle alone there never could have been +any Motion in the World. Some other Principle was necessary for putting +Bodies into Motion; and now they are in Motion, some other Principle is +necessary for conserving the Motion. For from the various Composition of +two Motions, 'tis very certain that there is not always the same +quantity of Motion in the World. For if two Globes joined by a slender +Rod, revolve about their common Center of Gravity with an uniform +Motion, while that Center moves on uniformly in a right Line drawn in +the Plane of their circular Motion; the Sum of the Motions of the two +Globes, as often as the Globes are in the right Line described by their +common Center of Gravity, will be bigger than the Sum of their Motions, +when they are in a Line perpendicular to that right Line. By this +Instance it appears that Motion may be got or lost. But by reason of the +Tenacity of Fluids, and Attrition of their Parts, and the Weakness of +Elasticity in Solids, Motion is much more apt to be lost than got, and +is always upon the Decay. For Bodies which are either absolutely hard, +or so soft as to be void of Elasticity, will not rebound from one +another. Impenetrability makes them only stop. If two equal Bodies meet +directly _in vacuo_, they will by the Laws of Motion stop where they +meet, and lose all their Motion, and remain in rest, unless they be +elastick, and receive new Motion from their Spring. If they have so much +Elasticity as suffices to make them re-bound with a quarter, or half, or +three quarters of the Force with which they come together, they will +lose three quarters, or half, or a quarter of their Motion. And this may +be try'd, by letting two equal Pendulums fall against one another from +equal heights. If the Pendulums be of Lead or soft Clay, they will lose +all or almost all their Motions: If of elastick Bodies they will lose +all but what they recover from their Elasticity. If it be said, that +they can lose no Motion but what they communicate to other Bodies, the +consequence is, that _in vacuo_ they can lose no Motion, but when they +meet they must go on and penetrate one another's Dimensions. If three +equal round Vessels be filled, the one with Water, the other with Oil, +the third with molten Pitch, and the Liquors be stirred about alike to +give them a vortical Motion; the Pitch by its Tenacity will lose its +Motion quickly, the Oil being less tenacious will keep it longer, and +the Water being less tenacious will keep it longest, but yet will lose +it in a short time. Whence it is easy to understand, that if many +contiguous Vortices of molten Pitch were each of them as large as those +which some suppose to revolve about the Sun and fix'd Stars, yet these +and all their Parts would, by their Tenacity and Stiffness, communicate +their Motion to one another till they all rested among themselves. +Vortices of Oil or Water, or some fluider Matter, might continue longer +in Motion; but unless the Matter were void of all Tenacity and Attrition +of Parts, and Communication of Motion, (which is not to be supposed,) +the Motion would constantly decay. Seeing therefore the variety of +Motion which we find in the World is always decreasing, there is a +necessity of conserving and recruiting it by active Principles, such as +are the cause of Gravity, by which Planets and Comets keep their Motions +in their Orbs, and Bodies acquire great Motion in falling; and the cause +of Fermentation, by which the Heart and Blood of Animals are kept in +perpetual Motion and Heat; the inward Parts of the Earth are constantly +warm'd, and in some places grow very hot; Bodies burn and shine, +Mountains take fire, the Caverns of the Earth are blown up, and the Sun +continues violently hot and lucid, and warms all things by his Light. +For we meet with very little Motion in the World, besides what is owing +to these active Principles. And if it were not for these Principles, the +Bodies of the Earth, Planets, Comets, Sun, and all things in them, +would grow cold and freeze, and become inactive Masses; and all +Putrefaction, Generation, Vegetation and Life would cease, and the +Planets and Comets would not remain in their Orbs. + +All these things being consider'd, it seems probable to me, that God in +the Beginning form'd Matter in solid, massy, hard, impenetrable, +moveable Particles, of such Sizes and Figures, and with such other +Properties, and in such Proportion to Space, as most conduced to the End +for which he form'd them; and that these primitive Particles being +Solids, are incomparably harder than any porous Bodies compounded of +them; even so very hard, as never to wear or break in pieces; no +ordinary Power being able to divide what God himself made one in the +first Creation. While the Particles continue entire, they may compose +Bodies of one and the same Nature and Texture in all Ages: But should +they wear away, or break in pieces, the Nature of Things depending on +them, would be changed. Water and Earth, composed of old worn Particles +and Fragments of Particles, would not be of the same Nature and Texture +now, with Water and Earth composed of entire Particles in the Beginning. +And therefore, that Nature may be lasting, the Changes of corporeal +Things are to be placed only in the various Separations and new +Associations and Motions of these permanent Particles; compound Bodies +being apt to break, not in the midst of solid Particles, but where those +Particles are laid together, and only touch in a few Points. + +It seems to me farther, that these Particles have not only a _Vis +inertiæ_, accompanied with such passive Laws of Motion as naturally +result from that Force, but also that they are moved by certain active +Principles, such as is that of Gravity, and that which causes +Fermentation, and the Cohesion of Bodies. These Principles I consider, +not as occult Qualities, supposed to result from the specifick Forms of +Things, but as general Laws of Nature, by which the Things themselves +are form'd; their Truth appearing to us by Phænomena, though their +Causes be not yet discover'd. For these are manifest Qualities, and +their Causes only are occult. And the _Aristotelians_ gave the Name of +occult Qualities, not to manifest Qualities, but to such Qualities only +as they supposed to lie hid in Bodies, and to be the unknown Causes of +manifest Effects: Such as would be the Causes of Gravity, and of +magnetick and electrick Attractions, and of Fermentations, if we should +suppose that these Forces or Actions arose from Qualities unknown to us, +and uncapable of being discovered and made manifest. Such occult +Qualities put a stop to the Improvement of natural Philosophy, and +therefore of late Years have been rejected. To tell us that every +Species of Things is endow'd with an occult specifick Quality by which +it acts and produces manifest Effects, is to tell us nothing: But to +derive two or three general Principles of Motion from Phænomena, and +afterwards to tell us how the Properties and Actions of all corporeal +Things follow from those manifest Principles, would be a very great step +in Philosophy, though the Causes of those Principles were not yet +discover'd: And therefore I scruple not to propose the Principles of +Motion above-mention'd, they being of very general Extent, and leave +their Causes to be found out. + +Now by the help of these Principles, all material Things seem to have +been composed of the hard and solid Particles above-mention'd, variously +associated in the first Creation by the Counsel of an intelligent Agent. +For it became him who created them to set them in order. And if he did +so, it's unphilosophical to seek for any other Origin of the World, or +to pretend that it might arise out of a Chaos by the mere Laws of +Nature; though being once form'd, it may continue by those Laws for many +Ages. For while Comets move in very excentrick Orbs in all manner of +Positions, blind Fate could never make all the Planets move one and the +same way in Orbs concentrick, some inconsiderable Irregularities +excepted, which may have risen from the mutual Actions of Comets and +Planets upon one another, and which will be apt to increase, till this +System wants a Reformation. Such a wonderful Uniformity in the Planetary +System must be allowed the Effect of Choice. And so must the Uniformity +in the Bodies of Animals, they having generally a right and a left side +shaped alike, and on either side of their Bodies two Legs behind, and +either two Arms, or two Legs, or two Wings before upon their Shoulders, +and between their Shoulders a Neck running down into a Back-bone, and a +Head upon it; and in the Head two Ears, two Eyes, a Nose, a Mouth, and +a Tongue, alike situated. Also the first Contrivance of those very +artificial Parts of Animals, the Eyes, Ears, Brain, Muscles, Heart, +Lungs, Midriff, Glands, Larynx, Hands, Wings, swimming Bladders, natural +Spectacles, and other Organs of Sense and Motion; and the Instinct of +Brutes and Insects, can be the effect of nothing else than the Wisdom +and Skill of a powerful ever-living Agent, who being in all Places, is +more able by his Will to move the Bodies within his boundless uniform +Sensorium, and thereby to form and reform the Parts of the Universe, +than we are by our Will to move the Parts of our own Bodies. And yet we +are not to consider the World as the Body of God, or the several Parts +thereof, as the Parts of God. He is an uniform Being, void of Organs, +Members or Parts, and they are his Creatures subordinate to him, and +subservient to his Will; and he is no more the Soul of them, than the +Soul of Man is the Soul of the Species of Things carried through the +Organs of Sense into the place of its Sensation, where it perceives them +by means of its immediate Presence, without the Intervention of any +third thing. The Organs of Sense are not for enabling the Soul to +perceive the Species of Things in its Sensorium, but only for conveying +them thither; and God has no need of such Organs, he being every where +present to the Things themselves. And since Space is divisible _in +infinitum_, and Matter is not necessarily in all places, it may be also +allow'd that God is able to create Particles of Matter of several Sizes +and Figures, and in several Proportions to Space, and perhaps of +different Densities and Forces, and thereby to vary the Laws of Nature, +and make Worlds of several sorts in several Parts of the Universe. At +least, I see nothing of Contradiction in all this. + +As in Mathematicks, so in Natural Philosophy, the Investigation of +difficult Things by the Method of Analysis, ought ever to precede the +Method of Composition. This Analysis consists in making Experiments and +Observations, and in drawing general Conclusions from them by Induction, +and admitting of no Objections against the Conclusions, but such as are +taken from Experiments, or other certain Truths. For Hypotheses are not +to be regarded in experimental Philosophy. And although the arguing from +Experiments and Observations by Induction be no Demonstration of general +Conclusions; yet it is the best way of arguing which the Nature of +Things admits of, and may be looked upon as so much the stronger, by how +much the Induction is more general. And if no Exception occur from +Phænomena, the Conclusion may be pronounced generally. But if at any +time afterwards any Exception shall occur from Experiments, it may then +begin to be pronounced with such Exceptions as occur. By this way of +Analysis we may proceed from Compounds to Ingredients, and from Motions +to the Forces producing them; and in general, from Effects to their +Causes, and from particular Causes to more general ones, till the +Argument end in the most general. This is the Method of Analysis: And +the Synthesis consists in assuming the Causes discover'd, and +establish'd as Principles, and by them explaining the Phænomena +proceeding from them, and proving the Explanations. + +In the two first Books of these Opticks, I proceeded by this Analysis to +discover and prove the original Differences of the Rays of Light in +respect of Refrangibility, Reflexibility, and Colour, and their +alternate Fits of easy Reflexion and easy Transmission, and the +Properties of Bodies, both opake and pellucid, on which their Reflexions +and Colours depend. And these Discoveries being proved, may be assumed +in the Method of Composition for explaining the Phænomena arising from +them: An Instance of which Method I gave in the End of the first Book. +In this third Book I have only begun the Analysis of what remains to be +discover'd about Light and its Effects upon the Frame of Nature, hinting +several things about it, and leaving the Hints to be examin'd and +improv'd by the farther Experiments and Observations of such as are +inquisitive. And if natural Philosophy in all its Parts, by pursuing +this Method, shall at length be perfected, the Bounds of Moral +Philosophy will be also enlarged. For so far as we can know by natural +Philosophy what is the first Cause, what Power he has over us, and what +Benefits we receive from him, so far our Duty towards him, as well as +that towards one another, will appear to us by the Light of Nature. And +no doubt, if the Worship of false Gods had not blinded the Heathen, +their moral Philosophy would have gone farther than to the four +Cardinal Virtues; and instead of teaching the Transmigration of Souls, +and to worship the Sun and Moon, and dead Heroes, they would have taught +us to worship our true Author and Benefactor, as their Ancestors did +under the Government of _Noah_ and his Sons before they corrupted +themselves.
\ No newline at end of file diff --git a/src/testing/sub_test.go b/src/testing/sub_test.go index 9af3909b35..29803c06e2 100644 --- a/src/testing/sub_test.go +++ b/src/testing/sub_test.go @@ -594,8 +594,8 @@ func TestBRun(t *T) { func makeRegexp(s string) string { s = regexp.QuoteMeta(s) - s = strings.Replace(s, ":NNN:", `:\d\d\d:`, -1) - s = strings.Replace(s, "N\\.NNs", `\d*\.\d*s`, -1) + s = strings.ReplaceAll(s, ":NNN:", `:\d\d\d:`) + s = strings.ReplaceAll(s, "N\\.NNs", `\d*\.\d*s`) return s } diff --git a/src/text/template/exec.go b/src/text/template/exec.go index 214f72d51b..1d04c2982f 100644 --- a/src/text/template/exec.go +++ b/src/text/template/exec.go @@ -102,7 +102,7 @@ func (s *state) at(node parse.Node) { // doublePercent returns the string with %'s replaced by %%, if necessary, // so it can be used safely inside a Printf format string. func doublePercent(str string) string { - return strings.Replace(str, "%", "%%", -1) + return strings.ReplaceAll(str, "%", "%%") } // TODO: It would be nice if ExecError was more broken down, but diff --git a/src/time/zoneinfo.go b/src/time/zoneinfo.go index d2bc642d81..54c76f09e1 100644 --- a/src/time/zoneinfo.go +++ b/src/time/zoneinfo.go @@ -288,14 +288,23 @@ func LoadLocation(name string) (*Location, error) { env, _ := syscall.Getenv("ZONEINFO") zoneinfo = &env }) + var firstErr error if *zoneinfo != "" { if zoneData, err := loadTzinfoFromDirOrZip(*zoneinfo, name); err == nil { if z, err := LoadLocationFromTZData(name, zoneData); err == nil { return z, nil } + firstErr = err + } else if err != syscall.ENOENT { + firstErr = err } } - return loadLocation(name, zoneSources) + if z, err := loadLocation(name, zoneSources); err == nil { + return z, nil + } else if firstErr == nil { + firstErr = err + } + return nil, firstErr } // containsDotDot reports whether s contains "..". diff --git a/src/time/zoneinfo_android.go b/src/time/zoneinfo_android.go index 65e0975ab0..237ff202f9 100644 --- a/src/time/zoneinfo_android.go +++ b/src/time/zoneinfo_android.go @@ -11,6 +11,7 @@ package time import ( "errors" "runtime" + "syscall" ) var zoneSources = []string{ @@ -75,5 +76,5 @@ func androidLoadTzinfoFromTzdata(file, name string) ([]byte, error) { } return buf, nil } - return nil, errors.New("cannot find " + name + " in tzdata file " + file) + return nil, syscall.ENOENT } diff --git a/src/time/zoneinfo_read.go b/src/time/zoneinfo_read.go index 29244db29e..15d6aab1de 100644 --- a/src/time/zoneinfo_read.go +++ b/src/time/zoneinfo_read.go @@ -364,7 +364,7 @@ func loadTzinfoFromZip(zipfile, name string) ([]byte, error) { return buf, nil } - return nil, errors.New("cannot find " + name + " in zip file " + zipfile) + return nil, syscall.ENOENT } // loadTzinfoFromTzdata returns the time zone information of the time zone diff --git a/src/time/zoneinfo_test.go b/src/time/zoneinfo_test.go index 450f5aa114..4458ba8e26 100644 --- a/src/time/zoneinfo_test.go +++ b/src/time/zoneinfo_test.go @@ -5,6 +5,7 @@ package time_test import ( + "errors" "fmt" "os" "reflect" @@ -36,6 +37,16 @@ func TestEnvVarUsage(t *testing.T) { } } +func TestBadLocationErrMsg(t *testing.T) { + time.ResetZoneinfoForTesting() + loc := "Asia/SomethingNotExist" + want := errors.New("unknown time zone " + loc) + _, err := time.LoadLocation(loc) + if err.Error() != want.Error() { + t.Errorf("LoadLocation(%q) error = %v; want %v", loc, err, want) + } +} + func TestLoadLocationValidatesNames(t *testing.T) { time.ResetZoneinfoForTesting() const env = "ZONEINFO" |