diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/cmd/compile/internal/ssa/gen/ARM64.rules | 7 | ||||
| -rw-r--r-- | src/cmd/compile/internal/ssa/rewriteARM64.go | 48 |
2 files changed, 55 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/ssa/gen/ARM64.rules b/src/cmd/compile/internal/ssa/gen/ARM64.rules index 3f49a9bcf9..133a893610 100644 --- a/src/cmd/compile/internal/ssa/gen/ARM64.rules +++ b/src/cmd/compile/internal/ssa/gen/ARM64.rules @@ -133,6 +133,13 @@ (BitRev16 x) -> (SRLconst [48] (RBIT <typ.UInt64> x)) (BitRev8 x) -> (SRLconst [56] (RBIT <typ.UInt64> x)) +// In fact, UMOD will be translated into UREM instruction, and UREM is originally translated into +// UDIV and MSUB instructions. But if there is already an identical UDIV instruction just before or +// after UREM (case like quo, rem := z/y, z%y), then the second UDIV instruction becomes redundant. +// The purpose of this rule is to have this extra UDIV instruction removed in CSE pass. +(UMOD <typ.UInt64> x y) -> (MSUB <typ.UInt64> x y (UDIV <typ.UInt64> x y)) +(UMODW <typ.UInt32> x y) -> (MSUBW <typ.UInt32> x y (UDIVW <typ.UInt32> x y)) + // boolean ops -- booleans are represented with 0=false, 1=true (AndB x y) -> (AND x y) (OrB x y) -> (OR x y) diff --git a/src/cmd/compile/internal/ssa/rewriteARM64.go b/src/cmd/compile/internal/ssa/rewriteARM64.go index fe815efb14..45801a4003 100644 --- a/src/cmd/compile/internal/ssa/rewriteARM64.go +++ b/src/cmd/compile/internal/ssa/rewriteARM64.go @@ -30667,6 +30667,30 @@ func rewriteValueARM64_OpARM64UDIVW_0(v *Value) bool { return false } func rewriteValueARM64_OpARM64UMOD_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ + // match: (UMOD <typ.UInt64> x y) + // cond: + // result: (MSUB <typ.UInt64> x y (UDIV <typ.UInt64> x y)) + for { + if v.Type != typ.UInt64 { + break + } + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + v.reset(OpARM64MSUB) + v.Type = typ.UInt64 + v.AddArg(x) + v.AddArg(y) + v0 := b.NewValue0(v.Pos, OpARM64UDIV, typ.UInt64) + v0.AddArg(x) + v0.AddArg(y) + v.AddArg(v0) + return true + } // match: (UMOD _ (MOVDconst [1])) // cond: // result: (MOVDconst [0]) @@ -30724,6 +30748,30 @@ func rewriteValueARM64_OpARM64UMOD_0(v *Value) bool { return false } func rewriteValueARM64_OpARM64UMODW_0(v *Value) bool { + b := v.Block + _ = b + typ := &b.Func.Config.Types + _ = typ + // match: (UMODW <typ.UInt32> x y) + // cond: + // result: (MSUBW <typ.UInt32> x y (UDIVW <typ.UInt32> x y)) + for { + if v.Type != typ.UInt32 { + break + } + _ = v.Args[1] + x := v.Args[0] + y := v.Args[1] + v.reset(OpARM64MSUBW) + v.Type = typ.UInt32 + v.AddArg(x) + v.AddArg(y) + v0 := b.NewValue0(v.Pos, OpARM64UDIVW, typ.UInt32) + v0.AddArg(x) + v0.AddArg(y) + v.AddArg(v0) + return true + } // match: (UMODW _ (MOVDconst [c])) // cond: uint32(c)==1 // result: (MOVDconst [0]) |