cmd/compile: remove Zero and NilCheck for newobject
Recognize runtime.newobject and don't Zero or NilCheck it.
Fixes #15914 (?)
Updates #15390.
TBD: add test
Change-Id: Ia3bfa5c2ddbe2c27c92d9f68534a713b5ce95934
Reviewed-on: https://go-review.googlesource.com/27930
Run-TryBot: Cherry Zhang <cherryyz@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 8153703..d041afd 100644
--- a/src/cmd/compile/internal/ssa/rewritegeneric.go
+++ b/src/cmd/compile/internal/ssa/rewritegeneric.go
@@ -358,6 +358,8 @@
return rewriteValuegeneric_OpXor64(v, config)
case OpXor8:
return rewriteValuegeneric_OpXor8(v, config)
+ case OpZero:
+ return rewriteValuegeneric_OpZero(v, config)
}
return false
}
@@ -10969,7 +10971,43 @@
}
return false
}
-func rewriteBlockgeneric(b *Block) bool {
+func rewriteValuegeneric_OpZero(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Zero (Load (OffPtr [c] (SP)) mem:(StaticCall {sym} _)) mem2)
+ // cond: c == config.ctxt.FixedFrameSize() + config.PtrSize && mem2 == mem && isSameSym(sym, "runtime.newobject")
+ // result: mem
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpLoad {
+ break
+ }
+ v_0_0 := v_0.Args[0]
+ if v_0_0.Op != OpOffPtr {
+ break
+ }
+ c := v_0_0.AuxInt
+ v_0_0_0 := v_0_0.Args[0]
+ if v_0_0_0.Op != OpSP {
+ break
+ }
+ mem := v_0.Args[1]
+ if mem.Op != OpStaticCall {
+ break
+ }
+ sym := mem.Aux
+ mem2 := v.Args[1]
+ if !(c == config.ctxt.FixedFrameSize()+config.PtrSize && mem2 == mem && isSameSym(sym, "runtime.newobject")) {
+ break
+ }
+ v.reset(OpCopy)
+ v.Type = mem.Type
+ v.AddArg(mem)
+ return true
+ }
+ return false
+}
+func rewriteBlockgeneric(b *Block, config *Config) bool {
switch b.Kind {
case BlockCheck:
// match: (Check (NilCheck (GetG _) _) next)
@@ -10990,6 +11028,80 @@
_ = next
return true
}
+ // match: (Check (NilCheck (Load (OffPtr [c] (SP)) mem:(StaticCall {sym} _)) _) succ)
+ // cond: c == config.ctxt.FixedFrameSize() + config.PtrSize && isSameSym(sym, "runtime.newobject")
+ // result: (Plain nil succ)
+ for {
+ v := b.Control
+ if v.Op != OpNilCheck {
+ break
+ }
+ v_0 := v.Args[0]
+ if v_0.Op != OpLoad {
+ break
+ }
+ v_0_0 := v_0.Args[0]
+ if v_0_0.Op != OpOffPtr {
+ break
+ }
+ c := v_0_0.AuxInt
+ v_0_0_0 := v_0_0.Args[0]
+ if v_0_0_0.Op != OpSP {
+ break
+ }
+ mem := v_0.Args[1]
+ if mem.Op != OpStaticCall {
+ break
+ }
+ sym := mem.Aux
+ succ := b.Succs[0]
+ if !(c == config.ctxt.FixedFrameSize()+config.PtrSize && isSameSym(sym, "runtime.newobject")) {
+ break
+ }
+ b.Kind = BlockPlain
+ b.SetControl(nil)
+ _ = succ
+ return true
+ }
+ // match: (Check (NilCheck (OffPtr (Load (OffPtr [c] (SP)) mem:(StaticCall {sym} _))) _) succ)
+ // cond: c == config.ctxt.FixedFrameSize() + config.PtrSize && isSameSym(sym, "runtime.newobject")
+ // result: (Plain nil succ)
+ for {
+ v := b.Control
+ if v.Op != OpNilCheck {
+ break
+ }
+ v_0 := v.Args[0]
+ if v_0.Op != OpOffPtr {
+ break
+ }
+ v_0_0 := v_0.Args[0]
+ if v_0_0.Op != OpLoad {
+ break
+ }
+ v_0_0_0 := v_0_0.Args[0]
+ if v_0_0_0.Op != OpOffPtr {
+ break
+ }
+ c := v_0_0_0.AuxInt
+ v_0_0_0_0 := v_0_0_0.Args[0]
+ if v_0_0_0_0.Op != OpSP {
+ break
+ }
+ mem := v_0_0.Args[1]
+ if mem.Op != OpStaticCall {
+ break
+ }
+ sym := mem.Aux
+ succ := b.Succs[0]
+ if !(c == config.ctxt.FixedFrameSize()+config.PtrSize && isSameSym(sym, "runtime.newobject")) {
+ break
+ }
+ b.Kind = BlockPlain
+ b.SetControl(nil)
+ _ = succ
+ return true
+ }
case BlockIf:
// match: (If (Not cond) yes no)
// cond:
