[dev.ssa] cmd/compile/internal/ssa: constant fold truncates and bool comparisons
Change-Id: I731722eb77f373ff7d6101f93830ab0a50497e2c
Reviewed-on: https://go-review.googlesource.com/19542
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
diff --git a/src/cmd/compile/internal/ssa/rewritegeneric.go b/src/cmd/compile/internal/ssa/rewritegeneric.go
index c6fcb22..ae36112 100644
--- a/src/cmd/compile/internal/ssa/rewritegeneric.go
+++ b/src/cmd/compile/internal/ssa/rewritegeneric.go
@@ -303,6 +303,18 @@
return rewriteValuegeneric_OpSub64(v, config)
case OpSub8:
return rewriteValuegeneric_OpSub8(v, config)
+ case OpTrunc16to8:
+ return rewriteValuegeneric_OpTrunc16to8(v, config)
+ case OpTrunc32to16:
+ return rewriteValuegeneric_OpTrunc32to16(v, config)
+ case OpTrunc32to8:
+ return rewriteValuegeneric_OpTrunc32to8(v, config)
+ case OpTrunc64to16:
+ return rewriteValuegeneric_OpTrunc64to16(v, config)
+ case OpTrunc64to32:
+ return rewriteValuegeneric_OpTrunc64to32(v, config)
+ case OpTrunc64to8:
+ return rewriteValuegeneric_OpTrunc64to8(v, config)
case OpXor16:
return rewriteValuegeneric_OpXor16(v, config)
case OpXor32:
@@ -1899,6 +1911,53 @@
v.AuxInt = 1
return true
}
+ // match: (Eq8 (ConstBool [c]) (ConstBool [d]))
+ // cond:
+ // result: (ConstBool [b2i((int8(c) != 0) == (int8(d) != 0))])
+ for {
+ if v.Args[0].Op != OpConstBool {
+ break
+ }
+ c := v.Args[0].AuxInt
+ if v.Args[1].Op != OpConstBool {
+ break
+ }
+ d := v.Args[1].AuxInt
+ v.reset(OpConstBool)
+ v.AuxInt = b2i((int8(c) != 0) == (int8(d) != 0))
+ return true
+ }
+ // match: (Eq8 (ConstBool [0]) x)
+ // cond:
+ // result: (Not x)
+ for {
+ if v.Args[0].Op != OpConstBool {
+ break
+ }
+ if v.Args[0].AuxInt != 0 {
+ break
+ }
+ x := v.Args[1]
+ v.reset(OpNot)
+ v.AddArg(x)
+ return true
+ }
+ // match: (Eq8 (ConstBool [1]) x)
+ // cond:
+ // result: x
+ for {
+ if v.Args[0].Op != OpConstBool {
+ break
+ }
+ if v.Args[0].AuxInt != 1 {
+ break
+ }
+ x := v.Args[1]
+ v.reset(OpCopy)
+ v.Type = x.Type
+ v.AddArg(x)
+ return true
+ }
// match: (Eq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x))
// cond:
// result: (Eq8 (Const8 <t> [c-d]) x)
@@ -1946,6 +2005,26 @@
v.AddArg(x)
return true
}
+ // match: (Eq8 x (ConstBool <t> [c]))
+ // cond: x.Op != OpConstBool
+ // result: (Eq8 (ConstBool <t> [c]) x)
+ for {
+ x := v.Args[0]
+ if v.Args[1].Op != OpConstBool {
+ break
+ }
+ t := v.Args[1].Type
+ c := v.Args[1].AuxInt
+ if !(x.Op != OpConstBool) {
+ break
+ }
+ v.reset(OpEq8)
+ v0 := b.NewValue0(v.Line, OpConstBool, t)
+ v0.AuxInt = c
+ v.AddArg(v0)
+ v.AddArg(x)
+ return true
+ }
// match: (Eq8 (Const8 [c]) (Const8 [d]))
// cond:
// result: (ConstBool [b2i(int8(c) == int8(d))])
@@ -4429,6 +4508,53 @@
v.AuxInt = 0
return true
}
+ // match: (Neq8 (ConstBool [c]) (ConstBool [d]))
+ // cond:
+ // result: (ConstBool [b2i((int8(c) != 0) != (int8(d) != 0))])
+ for {
+ if v.Args[0].Op != OpConstBool {
+ break
+ }
+ c := v.Args[0].AuxInt
+ if v.Args[1].Op != OpConstBool {
+ break
+ }
+ d := v.Args[1].AuxInt
+ v.reset(OpConstBool)
+ v.AuxInt = b2i((int8(c) != 0) != (int8(d) != 0))
+ return true
+ }
+ // match: (Neq8 (ConstBool [0]) x)
+ // cond:
+ // result: x
+ for {
+ if v.Args[0].Op != OpConstBool {
+ break
+ }
+ if v.Args[0].AuxInt != 0 {
+ break
+ }
+ x := v.Args[1]
+ v.reset(OpCopy)
+ v.Type = x.Type
+ v.AddArg(x)
+ return true
+ }
+ // match: (Neq8 (ConstBool [1]) x)
+ // cond:
+ // result: (Not x)
+ for {
+ if v.Args[0].Op != OpConstBool {
+ break
+ }
+ if v.Args[0].AuxInt != 1 {
+ break
+ }
+ x := v.Args[1]
+ v.reset(OpNot)
+ v.AddArg(x)
+ return true
+ }
// match: (Neq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x))
// cond:
// result: (Neq8 (Const8 <t> [c-d]) x)
@@ -4476,6 +4602,26 @@
v.AddArg(x)
return true
}
+ // match: (Neq8 x (ConstBool <t> [c]))
+ // cond: x.Op != OpConstBool
+ // result: (Neq8 (ConstBool <t> [c]) x)
+ for {
+ x := v.Args[0]
+ if v.Args[1].Op != OpConstBool {
+ break
+ }
+ t := v.Args[1].Type
+ c := v.Args[1].AuxInt
+ if !(x.Op != OpConstBool) {
+ break
+ }
+ v.reset(OpNeq8)
+ v0 := b.NewValue0(v.Line, OpConstBool, t)
+ v0.AuxInt = c
+ v.AddArg(v0)
+ v.AddArg(x)
+ return true
+ }
// match: (Neq8 (Const8 [c]) (Const8 [d]))
// cond:
// result: (ConstBool [b2i(int8(c) != int8(d))])
@@ -7275,6 +7421,108 @@
}
return false
}
+func rewriteValuegeneric_OpTrunc16to8(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Trunc16to8 (Const16 [c]))
+ // cond:
+ // result: (Const8 [int64(int8(c))])
+ for {
+ if v.Args[0].Op != OpConst16 {
+ break
+ }
+ c := v.Args[0].AuxInt
+ v.reset(OpConst8)
+ v.AuxInt = int64(int8(c))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpTrunc32to16(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Trunc32to16 (Const32 [c]))
+ // cond:
+ // result: (Const16 [int64(int16(c))])
+ for {
+ if v.Args[0].Op != OpConst32 {
+ break
+ }
+ c := v.Args[0].AuxInt
+ v.reset(OpConst16)
+ v.AuxInt = int64(int16(c))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpTrunc32to8(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Trunc32to8 (Const32 [c]))
+ // cond:
+ // result: (Const8 [int64(int8(c))])
+ for {
+ if v.Args[0].Op != OpConst32 {
+ break
+ }
+ c := v.Args[0].AuxInt
+ v.reset(OpConst8)
+ v.AuxInt = int64(int8(c))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpTrunc64to16(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Trunc64to16 (Const64 [c]))
+ // cond:
+ // result: (Const16 [int64(int16(c))])
+ for {
+ if v.Args[0].Op != OpConst64 {
+ break
+ }
+ c := v.Args[0].AuxInt
+ v.reset(OpConst16)
+ v.AuxInt = int64(int16(c))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpTrunc64to32(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Trunc64to32 (Const64 [c]))
+ // cond:
+ // result: (Const32 [int64(int32(c))])
+ for {
+ if v.Args[0].Op != OpConst64 {
+ break
+ }
+ c := v.Args[0].AuxInt
+ v.reset(OpConst32)
+ v.AuxInt = int64(int32(c))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpTrunc64to8(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Trunc64to8 (Const64 [c]))
+ // cond:
+ // result: (Const8 [int64(int8(c))])
+ for {
+ if v.Args[0].Op != OpConst64 {
+ break
+ }
+ c := v.Args[0].AuxInt
+ v.reset(OpConst8)
+ v.AuxInt = int64(int8(c))
+ return true
+ }
+ return false
+}
func rewriteValuegeneric_OpXor16(v *Value, config *Config) bool {
b := v.Block
_ = b
