diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/cmd/compile/internal/ssa/gen/RISCV64.rules | 3 | ||||
| -rw-r--r-- | src/cmd/compile/internal/ssa/rewriteRISCV64.go | 25 |
2 files changed, 10 insertions, 18 deletions
diff --git a/src/cmd/compile/internal/ssa/gen/RISCV64.rules b/src/cmd/compile/internal/ssa/gen/RISCV64.rules index 1ffb9575e0..316e5f3726 100644 --- a/src/cmd/compile/internal/ssa/gen/RISCV64.rules +++ b/src/cmd/compile/internal/ssa/gen/RISCV64.rules @@ -141,8 +141,7 @@ // For positive x, bit 63 of x-1 is always 0, so the result is -1. // For zero x, bit 63 of x-1 is 1, so the result is 0. // -// TODO(prattmic): Use XORconst etc instead of XOR (MOVDconst). -(Slicemask <t> x) -> (XOR (MOVDconst [-1]) (SRA <t> (SUB <t> x (MOVDconst [1])) (MOVDconst [63]))) +(Slicemask <t> x) -> (XORI [-1] (SRAI <t> [63] (ADDI <t> [-1] x))) // Truncations // We ignore the unused high parts of registers, so truncates are just copies. diff --git a/src/cmd/compile/internal/ssa/rewriteRISCV64.go b/src/cmd/compile/internal/ssa/rewriteRISCV64.go index 61da7a41bd..3b8d42b035 100644 --- a/src/cmd/compile/internal/ssa/rewriteRISCV64.go +++ b/src/cmd/compile/internal/ssa/rewriteRISCV64.go @@ -4230,27 +4230,20 @@ func rewriteValueRISCV64_OpSignExt8to64(v *Value) bool { func rewriteValueRISCV64_OpSlicemask(v *Value) bool { v_0 := v.Args[0] b := v.Block - typ := &b.Func.Config.Types // match: (Slicemask <t> x) - // result: (XOR (MOVDconst [-1]) (SRA <t> (SUB <t> x (MOVDconst [1])) (MOVDconst [63]))) + // result: (XORI [-1] (SRAI <t> [63] (ADDI <t> [-1] x))) for { t := v.Type x := v_0 - v.reset(OpRISCV64XOR) - v0 := b.NewValue0(v.Pos, OpRISCV64MOVDconst, typ.UInt64) - v0.AuxInt = -1 + v.reset(OpRISCV64XORI) + v.AuxInt = -1 + v0 := b.NewValue0(v.Pos, OpRISCV64SRAI, t) + v0.AuxInt = 63 + v1 := b.NewValue0(v.Pos, OpRISCV64ADDI, t) + v1.AuxInt = -1 + v1.AddArg(x) + v0.AddArg(v1) v.AddArg(v0) - v1 := b.NewValue0(v.Pos, OpRISCV64SRA, t) - v2 := b.NewValue0(v.Pos, OpRISCV64SUB, t) - v2.AddArg(x) - v3 := b.NewValue0(v.Pos, OpRISCV64MOVDconst, typ.UInt64) - v3.AuxInt = 1 - v2.AddArg(v3) - v1.AddArg(v2) - v4 := b.NewValue0(v.Pos, OpRISCV64MOVDconst, typ.UInt64) - v4.AuxInt = 63 - v1.AddArg(v4) - v.AddArg(v1) return true } } |