qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-24 17:30:18 -07:00
Code Releases Activity

[dev.ssa] cmd/compile/internal/ssa: replace load of store with a copy

Browse Source 
This is a AMD64 version of CL19743.
Saves additional 1574 bytes in go binary.
This also speeds up bzip2 by 1-4%

Change-Id: I031ba423663c4e83fdefe44e5296f24143e303da
Reviewed-on: https://go-review.googlesource.com/19939
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
This commit is contained in:
Ilya Tocar 2016-02-26 17:23:44 +03:00 committed by David Chase
parent 1b1d0a9a80
commit 5c5fa3628c
2 changed files with 94 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
src/cmd/compile/internal/ssa/gen/AMD64.rules
View File

@ -608,6 +608,12 @@
(MOVLQSX (MOVLload [off] {sym} ptr mem)) -> @v.Args[0].Block (MOVLQSXload <v.Type> [off] {sym} ptr mem)
(MOVLQZX (MOVLload [off] {sym} ptr mem)) -> @v.Args[0].Block (MOVLQZXload <v.Type> [off] {sym} ptr mem)
// replace load from same location as preceding store with copy
(MOVBload [off] {sym} ptr (MOVBstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
(MOVWload [off] {sym} ptr (MOVWstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
(MOVLload [off] {sym} ptr (MOVLstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
(MOVQload [off] {sym} ptr (MOVQstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> x
// Fold extensions and ANDs together.
(MOVBQZX (ANDBconst [c] x)) -> (ANDQconst [c & 0xff] x)
(MOVWQZX (ANDWconst [c] x)) -> (ANDQconst [c & 0xffff] x)

88
src/cmd/compile/internal/ssa/rewriteAMD64.go
View File

@ -5459,6 +5459,28 @@ func rewriteValueAMD64_OpAMD64MOVBQZX(v *Value, config *Config) bool {
func rewriteValueAMD64_OpAMD64MOVBload(v *Value, config *Config) bool {
b := v.Block
_ = b
// match: (MOVBload [off] {sym} ptr (MOVBstore [off2] {sym2} ptr2 x _))
// cond: sym == sym2 && off == off2 && isSamePtr(ptr, ptr2)
// result: x
for {
off := v.AuxInt
sym := v.Aux
ptr := v.Args[0]
if v.Args[1].Op != OpAMD64MOVBstore {
break
}
off2 := v.Args[1].AuxInt
sym2 := v.Args[1].Aux
ptr2 := v.Args[1].Args[0]
x := v.Args[1].Args[1]
if !(sym == sym2 && off == off2 && isSamePtr(ptr, ptr2)) {
break
}
v.reset(OpCopy)
v.Type = x.Type
v.AddArg(x)
return true
}
// match: (MOVBload [off1] {sym} (ADDQconst [off2] ptr) mem)
// cond:
// result: (MOVBload [addOff(off1, off2)] {sym} ptr mem)
@ -6042,6 +6064,28 @@ func rewriteValueAMD64_OpAMD64MOVLQZX(v *Value, config *Config) bool {
func rewriteValueAMD64_OpAMD64MOVLload(v *Value, config *Config) bool {
b := v.Block
_ = b
// match: (MOVLload [off] {sym} ptr (MOVLstore [off2] {sym2} ptr2 x _))
// cond: sym == sym2 && off == off2 && isSamePtr(ptr, ptr2)
// result: x
for {
off := v.AuxInt
sym := v.Aux
ptr := v.Args[0]
if v.Args[1].Op != OpAMD64MOVLstore {
break
}
off2 := v.Args[1].AuxInt
sym2 := v.Args[1].Aux
ptr2 := v.Args[1].Args[0]
x := v.Args[1].Args[1]
if !(sym == sym2 && off == off2 && isSamePtr(ptr, ptr2)) {
break
}
v.reset(OpCopy)
v.Type = x.Type
v.AddArg(x)
return true
}
// match: (MOVLload [off1] {sym} (ADDQconst [off2] ptr) mem)
// cond:
// result: (MOVLload [addOff(off1, off2)] {sym} ptr mem)
@ -6572,6 +6616,28 @@ func rewriteValueAMD64_OpAMD64MOVOstore(v *Value, config *Config) bool {
func rewriteValueAMD64_OpAMD64MOVQload(v *Value, config *Config) bool {
b := v.Block
_ = b
// match: (MOVQload [off] {sym} ptr (MOVQstore [off2] {sym2} ptr2 x _))
// cond: sym == sym2 && off == off2 && isSamePtr(ptr, ptr2)
// result: x
for {
off := v.AuxInt
sym := v.Aux
ptr := v.Args[0]
if v.Args[1].Op != OpAMD64MOVQstore {
break
}
off2 := v.Args[1].AuxInt
sym2 := v.Args[1].Aux
ptr2 := v.Args[1].Args[0]
x := v.Args[1].Args[1]
if !(sym == sym2 && off == off2 && isSamePtr(ptr, ptr2)) {
break
}
v.reset(OpCopy)
v.Type = x.Type
v.AddArg(x)
return true
}
// match: (MOVQload [off1] {sym} (ADDQconst [off2] ptr) mem)
// cond:
// result: (MOVQload [addOff(off1, off2)] {sym} ptr mem)
@ -7543,6 +7609,28 @@ func rewriteValueAMD64_OpAMD64MOVWQZX(v *Value, config *Config) bool {
func rewriteValueAMD64_OpAMD64MOVWload(v *Value, config *Config) bool {
b := v.Block
_ = b
// match: (MOVWload [off] {sym} ptr (MOVWstore [off2] {sym2} ptr2 x _))
// cond: sym == sym2 && off == off2 && isSamePtr(ptr, ptr2)
// result: x
for {
off := v.AuxInt
sym := v.Aux
ptr := v.Args[0]
if v.Args[1].Op != OpAMD64MOVWstore {
break
}
off2 := v.Args[1].AuxInt
sym2 := v.Args[1].Aux
ptr2 := v.Args[1].Args[0]
x := v.Args[1].Args[1]
if !(sym == sym2 && off == off2 && isSamePtr(ptr, ptr2)) {
break
}
v.reset(OpCopy)
v.Type = x.Type
v.AddArg(x)
return true
}
// match: (MOVWload [off1] {sym} (ADDQconst [off2] ptr) mem)
// cond:
// result: (MOVWload [addOff(off1, off2)] {sym} ptr mem)