cmd/compile: fold constants from lsh/rsh/lsh and rsh/lsh/rsh
Fixes #14825
Change-Id: Ib44d80579a55c15d75ea2ad1ef54efa6ca66a9a6
Reviewed-on: https://go-review.googlesource.com/20745
Run-TryBot: Todd Neal <todd@tneal.org>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/cmd/compile/internal/ssa/rewritegeneric.go b/src/cmd/compile/internal/ssa/rewritegeneric.go
index 815468d..4ed4cbf 100644
--- a/src/cmd/compile/internal/ssa/rewritegeneric.go
+++ b/src/cmd/compile/internal/ssa/rewritegeneric.go
@@ -3420,6 +3420,39 @@
func rewriteValuegeneric_OpLsh16x16(v *Value, config *Config) bool {
b := v.Block
_ = b
+ // match: (Lsh16x16 (Rsh16Ux16 (Lsh16x16 x (Const16 [c1])) (Const16 [c2])) (Const16 [c3]))
+ // cond: c1 >= c2 && c3 >= c2
+ // result: (Lsh16x16 x (Const16 <config.fe.TypeUInt16()> [c1-c2+c3]))
+ for {
+ if v.Args[0].Op != OpRsh16Ux16 {
+ break
+ }
+ if v.Args[0].Args[0].Op != OpLsh16x16 {
+ break
+ }
+ x := v.Args[0].Args[0].Args[0]
+ if v.Args[0].Args[0].Args[1].Op != OpConst16 {
+ break
+ }
+ c1 := v.Args[0].Args[0].Args[1].AuxInt
+ if v.Args[0].Args[1].Op != OpConst16 {
+ break
+ }
+ c2 := v.Args[0].Args[1].AuxInt
+ if v.Args[1].Op != OpConst16 {
+ break
+ }
+ c3 := v.Args[1].AuxInt
+ if !(c1 >= c2 && c3 >= c2) {
+ break
+ }
+ v.reset(OpLsh16x16)
+ v.AddArg(x)
+ v0 := b.NewValue0(v.Line, OpConst16, config.fe.TypeUInt16())
+ v0.AuxInt = c1 - c2 + c3
+ v.AddArg(v0)
+ return true
+ }
// match: (Lsh16x16 <t> x (Const16 [c]))
// cond:
// result: (Lsh16x64 x (Const64 <t> [int64(uint16(c))]))
@@ -3601,6 +3634,39 @@
func rewriteValuegeneric_OpLsh32x32(v *Value, config *Config) bool {
b := v.Block
_ = b
+ // match: (Lsh32x32 (Rsh32Ux32 (Lsh32x32 x (Const32 [c1])) (Const32 [c2])) (Const32 [c3]))
+ // cond: c1 >= c2 && c3 >= c2
+ // result: (Lsh32x32 x (Const32 <config.fe.TypeUInt32()> [c1-c2+c3]))
+ for {
+ if v.Args[0].Op != OpRsh32Ux32 {
+ break
+ }
+ if v.Args[0].Args[0].Op != OpLsh32x32 {
+ break
+ }
+ x := v.Args[0].Args[0].Args[0]
+ if v.Args[0].Args[0].Args[1].Op != OpConst32 {
+ break
+ }
+ c1 := v.Args[0].Args[0].Args[1].AuxInt
+ if v.Args[0].Args[1].Op != OpConst32 {
+ break
+ }
+ c2 := v.Args[0].Args[1].AuxInt
+ if v.Args[1].Op != OpConst32 {
+ break
+ }
+ c3 := v.Args[1].AuxInt
+ if !(c1 >= c2 && c3 >= c2) {
+ break
+ }
+ v.reset(OpLsh32x32)
+ v.AddArg(x)
+ v0 := b.NewValue0(v.Line, OpConst32, config.fe.TypeUInt32())
+ v0.AuxInt = c1 - c2 + c3
+ v.AddArg(v0)
+ return true
+ }
// match: (Lsh32x32 <t> x (Const32 [c]))
// cond:
// result: (Lsh32x64 x (Const64 <t> [int64(uint32(c))]))
@@ -3840,6 +3906,39 @@
v.AuxInt = 0
return true
}
+ // match: (Lsh64x64 (Rsh64Ux64 (Lsh64x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3]))
+ // cond: c1 >= c2 && c3 >= c2
+ // result: (Lsh64x64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3]))
+ for {
+ if v.Args[0].Op != OpRsh64Ux64 {
+ break
+ }
+ if v.Args[0].Args[0].Op != OpLsh64x64 {
+ break
+ }
+ x := v.Args[0].Args[0].Args[0]
+ if v.Args[0].Args[0].Args[1].Op != OpConst64 {
+ break
+ }
+ c1 := v.Args[0].Args[0].Args[1].AuxInt
+ if v.Args[0].Args[1].Op != OpConst64 {
+ break
+ }
+ c2 := v.Args[0].Args[1].AuxInt
+ if v.Args[1].Op != OpConst64 {
+ break
+ }
+ c3 := v.Args[1].AuxInt
+ if !(c1 >= c2 && c3 >= c2) {
+ break
+ }
+ v.reset(OpLsh64x64)
+ v.AddArg(x)
+ v0 := b.NewValue0(v.Line, OpConst64, config.fe.TypeUInt64())
+ v0.AuxInt = c1 - c2 + c3
+ v.AddArg(v0)
+ return true
+ }
// match: (Lsh64x64 x (Const64 [0]))
// cond:
// result: x
@@ -4090,6 +4189,39 @@
func rewriteValuegeneric_OpLsh8x8(v *Value, config *Config) bool {
b := v.Block
_ = b
+ // match: (Lsh8x8 (Rsh8Ux8 (Lsh8x8 x (Const8 [c1])) (Const8 [c2])) (Const8 [c3]))
+ // cond: c1 >= c2 && c3 >= c2
+ // result: (Lsh8x8 x (Const8 <config.fe.TypeUInt8()> [c1-c2+c3]))
+ for {
+ if v.Args[0].Op != OpRsh8Ux8 {
+ break
+ }
+ if v.Args[0].Args[0].Op != OpLsh8x8 {
+ break
+ }
+ x := v.Args[0].Args[0].Args[0]
+ if v.Args[0].Args[0].Args[1].Op != OpConst8 {
+ break
+ }
+ c1 := v.Args[0].Args[0].Args[1].AuxInt
+ if v.Args[0].Args[1].Op != OpConst8 {
+ break
+ }
+ c2 := v.Args[0].Args[1].AuxInt
+ if v.Args[1].Op != OpConst8 {
+ break
+ }
+ c3 := v.Args[1].AuxInt
+ if !(c1 >= c2 && c3 >= c2) {
+ break
+ }
+ v.reset(OpLsh8x8)
+ v.AddArg(x)
+ v0 := b.NewValue0(v.Line, OpConst8, config.fe.TypeUInt8())
+ v0.AuxInt = c1 - c2 + c3
+ v.AddArg(v0)
+ return true
+ }
// match: (Lsh8x8 <t> x (Const8 [c]))
// cond:
// result: (Lsh8x64 x (Const64 <t> [int64(uint8(c))]))
@@ -5524,6 +5656,39 @@
func rewriteValuegeneric_OpRsh16Ux16(v *Value, config *Config) bool {
b := v.Block
_ = b
+ // match: (Rsh16Ux16 (Lsh16x16 (Rsh16Ux16 x (Const16 [c1])) (Const16 [c2])) (Const16 [c3]))
+ // cond: c1 >= c2 && c3 >= c2
+ // result: (Rsh16Ux16 x (Const16 <config.fe.TypeUInt16()> [c1-c2+c3]))
+ for {
+ if v.Args[0].Op != OpLsh16x16 {
+ break
+ }
+ if v.Args[0].Args[0].Op != OpRsh16Ux16 {
+ break
+ }
+ x := v.Args[0].Args[0].Args[0]
+ if v.Args[0].Args[0].Args[1].Op != OpConst16 {
+ break
+ }
+ c1 := v.Args[0].Args[0].Args[1].AuxInt
+ if v.Args[0].Args[1].Op != OpConst16 {
+ break
+ }
+ c2 := v.Args[0].Args[1].AuxInt
+ if v.Args[1].Op != OpConst16 {
+ break
+ }
+ c3 := v.Args[1].AuxInt
+ if !(c1 >= c2 && c3 >= c2) {
+ break
+ }
+ v.reset(OpRsh16Ux16)
+ v.AddArg(x)
+ v0 := b.NewValue0(v.Line, OpConst16, config.fe.TypeUInt16())
+ v0.AuxInt = c1 - c2 + c3
+ v.AddArg(v0)
+ return true
+ }
// match: (Rsh16Ux16 <t> x (Const16 [c]))
// cond:
// result: (Rsh16Ux64 x (Const64 <t> [int64(uint16(c))]))
@@ -5849,6 +6014,39 @@
func rewriteValuegeneric_OpRsh32Ux32(v *Value, config *Config) bool {
b := v.Block
_ = b
+ // match: (Rsh32Ux32 (Lsh32x32 (Rsh32Ux32 x (Const32 [c1])) (Const32 [c2])) (Const32 [c3]))
+ // cond: c1 >= c2 && c3 >= c2
+ // result: (Rsh32Ux32 x (Const32 <config.fe.TypeUInt32()> [c1-c2+c3]))
+ for {
+ if v.Args[0].Op != OpLsh32x32 {
+ break
+ }
+ if v.Args[0].Args[0].Op != OpRsh32Ux32 {
+ break
+ }
+ x := v.Args[0].Args[0].Args[0]
+ if v.Args[0].Args[0].Args[1].Op != OpConst32 {
+ break
+ }
+ c1 := v.Args[0].Args[0].Args[1].AuxInt
+ if v.Args[0].Args[1].Op != OpConst32 {
+ break
+ }
+ c2 := v.Args[0].Args[1].AuxInt
+ if v.Args[1].Op != OpConst32 {
+ break
+ }
+ c3 := v.Args[1].AuxInt
+ if !(c1 >= c2 && c3 >= c2) {
+ break
+ }
+ v.reset(OpRsh32Ux32)
+ v.AddArg(x)
+ v0 := b.NewValue0(v.Line, OpConst32, config.fe.TypeUInt32())
+ v0.AuxInt = c1 - c2 + c3
+ v.AddArg(v0)
+ return true
+ }
// match: (Rsh32Ux32 <t> x (Const32 [c]))
// cond:
// result: (Rsh32Ux64 x (Const64 <t> [int64(uint32(c))]))
@@ -6232,6 +6430,39 @@
v.AuxInt = 0
return true
}
+ // match: (Rsh64Ux64 (Lsh64x64 (Rsh64Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3]))
+ // cond: c1 >= c2 && c3 >= c2
+ // result: (Rsh64Ux64 x (Const64 <config.fe.TypeUInt64()> [c1-c2+c3]))
+ for {
+ if v.Args[0].Op != OpLsh64x64 {
+ break
+ }
+ if v.Args[0].Args[0].Op != OpRsh64Ux64 {
+ break
+ }
+ x := v.Args[0].Args[0].Args[0]
+ if v.Args[0].Args[0].Args[1].Op != OpConst64 {
+ break
+ }
+ c1 := v.Args[0].Args[0].Args[1].AuxInt
+ if v.Args[0].Args[1].Op != OpConst64 {
+ break
+ }
+ c2 := v.Args[0].Args[1].AuxInt
+ if v.Args[1].Op != OpConst64 {
+ break
+ }
+ c3 := v.Args[1].AuxInt
+ if !(c1 >= c2 && c3 >= c2) {
+ break
+ }
+ v.reset(OpRsh64Ux64)
+ v.AddArg(x)
+ v0 := b.NewValue0(v.Line, OpConst64, config.fe.TypeUInt64())
+ v0.AuxInt = c1 - c2 + c3
+ v.AddArg(v0)
+ return true
+ }
// match: (Rsh64Ux64 x (Const64 [0]))
// cond:
// result: x
@@ -6682,6 +6913,39 @@
func rewriteValuegeneric_OpRsh8Ux8(v *Value, config *Config) bool {
b := v.Block
_ = b
+ // match: (Rsh8Ux8 (Lsh8x8 (Rsh8Ux8 x (Const8 [c1])) (Const8 [c2])) (Const8 [c3]))
+ // cond: c1 >= c2 && c3 >= c2
+ // result: (Rsh8Ux8 x (Const8 <config.fe.TypeUInt8()> [c1-c2+c3]))
+ for {
+ if v.Args[0].Op != OpLsh8x8 {
+ break
+ }
+ if v.Args[0].Args[0].Op != OpRsh8Ux8 {
+ break
+ }
+ x := v.Args[0].Args[0].Args[0]
+ if v.Args[0].Args[0].Args[1].Op != OpConst8 {
+ break
+ }
+ c1 := v.Args[0].Args[0].Args[1].AuxInt
+ if v.Args[0].Args[1].Op != OpConst8 {
+ break
+ }
+ c2 := v.Args[0].Args[1].AuxInt
+ if v.Args[1].Op != OpConst8 {
+ break
+ }
+ c3 := v.Args[1].AuxInt
+ if !(c1 >= c2 && c3 >= c2) {
+ break
+ }
+ v.reset(OpRsh8Ux8)
+ v.AddArg(x)
+ v0 := b.NewValue0(v.Line, OpConst8, config.fe.TypeUInt8())
+ v0.AuxInt = c1 - c2 + c3
+ v.AddArg(v0)
+ return true
+ }
// match: (Rsh8Ux8 <t> x (Const8 [c]))
// cond:
// result: (Rsh8Ux64 x (Const64 <t> [int64(uint8(c))]))
