qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-23 08:30:05 -07:00
Code Releases Activity

cmd/compile: remove ld/st-followed nil checks for PPC64

Browse Source 
Enabled checks (except for DUFF-ops which aren't implemented yet).
Added ppc64le to relevant test.

Also updated register list to reflect no-longer-reserved-
for-constants status (file was missed in that change).

Updates #16010.

Change-Id: I31b1aac19e14994f760f2ecd02edbeb1f78362e7
Reviewed-on: https://go-review.googlesource.com/28548
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This commit is contained in:
David Chase 2016-09-06 09:05:02 -07:00
parent b926bf83b0
commit 0e0ab20334
2 changed files with 66 additions and 61 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

125
src/cmd/compile/internal/ppc64/ssa.go
View File

@ -73,11 +73,11 @@ var ssaRegToReg = []int16{
ppc64.REG_F24,
ppc64.REG_F25,
ppc64.REG_F26,
// ppc64.REG_F27, // reserved for "floating conversion constant"
// ppc64.REG_F28, // 0.0
// ppc64.REG_F29, // 0.5
// ppc64.REG_F30, // 1.0
// ppc64.REG_F31, // 2.0
ppc64.REG_F27,
ppc64.REG_F28,
ppc64.REG_F29,
ppc64.REG_F30,
ppc64.REG_F31,
// ppc64.REG_CR0,
// ppc64.REG_CR1,
@ -94,6 +94,10 @@ var ssaRegToReg = []int16{
// ppc64.REG_CTR,
}
// Smallest possible faulting page at address zero,
// see ../../../../runtime/mheap.go:/minPhysPageSize
const minZeroPage = 4096
var condOps = map[ssa.Op]obj.As{
ssa.OpPPC64Equal: ppc64.ABEQ,
ssa.OpPPC64NotEqual: ppc64.ABNE,
@ -848,61 +852,62 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
case ssa.OpPPC64LoweredNilCheck:
// Optimization - if the subsequent block has a load or store
// at the same address, we don't need to issue this instruction.
// mem := v.Args[1]
// for _, w := range v.Block.Succs[0].Block().Values {
// if w.Op == ssa.OpPhi {
// if w.Type.IsMemory() {
// mem = w
// }
// continue
// }
// if len(w.Args) == 0 || !w.Args[len(w.Args)-1].Type.IsMemory() {
// // w doesn't use a store - can't be a memory op.
// continue
// }
// if w.Args[len(w.Args)-1] != mem {
// v.Fatalf("wrong store after nilcheck v=%s w=%s", v, w)
// }
// switch w.Op {
// case ssa.OpPPC64MOVBload, ssa.OpPPC64MOVBUload, ssa.OpPPC64MOVHload, ssa.OpPPC64MOVHUload,
// ssa.OpPPC64MOVWload, ssa.OpPPC64MOVFload, ssa.OpPPC64MOVDload,
// ssa.OpPPC64MOVBstore, ssa.OpPPC64MOVHstore, ssa.OpPPC64MOVWstore,
// ssa.OpPPC64MOVFstore, ssa.OpPPC64MOVDstore:
// // arg0 is ptr, auxint is offset
// if w.Args[0] == v.Args[0] && w.Aux == nil && w.AuxInt >= 0 && w.AuxInt < minZeroPage {
// if gc.Debug_checknil != 0 && int(v.Line) > 1 {
// gc.Warnl(v.Line, "removed nil check")
// }
// return
// }
// case ssa.OpPPC64DUFFZERO, ssa.OpPPC64LoweredZero, ssa.OpPPC64LoweredZeroU:
// // arg0 is ptr
// if w.Args[0] == v.Args[0] {
// if gc.Debug_checknil != 0 && int(v.Line) > 1 {
// gc.Warnl(v.Line, "removed nil check")
// }
// return
// }
// case ssa.OpPPC64DUFFCOPY, ssa.OpPPC64LoweredMove, ssa.OpPPC64LoweredMoveU:
// // arg0 is dst ptr, arg1 is src ptr
// if w.Args[0] == v.Args[0] || w.Args[1] == v.Args[0] {
// if gc.Debug_checknil != 0 && int(v.Line) > 1 {
// gc.Warnl(v.Line, "removed nil check")
// }
// return
// }
// default:
// }
// if w.Type.IsMemory() {
// if w.Op == ssa.OpVarDef || w.Op == ssa.OpVarKill || w.Op == ssa.OpVarLive {
// // these ops are OK
// mem = w
// continue
// }
// // We can't delay the nil check past the next store.
// break
// }
// }
mem := v.Args[1]
for _, w := range v.Block.Succs[0].Block().Values {
if w.Op == ssa.OpPhi {
if w.Type.IsMemory() {
mem = w
}
continue
}
if len(w.Args) == 0 || !w.Args[len(w.Args)-1].Type.IsMemory() {
// w doesn't use a store - can't be a memory op.
continue
}
if w.Args[len(w.Args)-1] != mem {
v.Fatalf("wrong store after nilcheck v=%s w=%s", v, w)
}
switch w.Op {
case ssa.OpPPC64MOVBload, ssa.OpPPC64MOVBZload, ssa.OpPPC64MOVHload, ssa.OpPPC64MOVHZload,
ssa.OpPPC64MOVWload, ssa.OpPPC64MOVWZload, ssa.OpPPC64MOVDload, ssa.OpPPC64FMOVDload, ssa.OpPPC64FMOVSload,
ssa.OpPPC64MOVBstore, ssa.OpPPC64MOVHstore, ssa.OpPPC64MOVWstore,
ssa.OpPPC64MOVDstore, ssa.OpPPC64FMOVSstore, ssa.OpPPC64FMOVDstore,
ssa.OpPPC64MOVDstorezero, ssa.OpPPC64MOVWstorezero, ssa.OpPPC64MOVHstorezero, ssa.OpPPC64MOVBstorezero:
// arg0 is ptr, auxint is offset
if w.Args[0] == v.Args[0] && w.Aux == nil && w.AuxInt >= 0 && w.AuxInt < minZeroPage {
if gc.Debug_checknil != 0 && int(v.Line) > 1 {
gc.Warnl(v.Line, "removed nil check")
}
return
}
case ssa.OpPPC64LoweredZero: // ssa.OpPPC64DUFFZERO,
// arg0 is ptr
if w.Args[0] == v.Args[0] {
if gc.Debug_checknil != 0 && int(v.Line) > 1 {
gc.Warnl(v.Line, "removed nil check")
}
return
}
case ssa.OpPPC64LoweredMove: // ssa.OpPPC64DUFFCOPY,
// arg0 is dst ptr, arg1 is src ptr
if w.Args[0] == v.Args[0] || w.Args[1] == v.Args[0] {
if gc.Debug_checknil != 0 && int(v.Line) > 1 {
gc.Warnl(v.Line, "removed nil check")
}
return
}
default:
}
if w.Type.IsMemory() {
if w.Op == ssa.OpVarDef || w.Op == ssa.OpVarKill || w.Op == ssa.OpVarLive {
// these ops are OK
mem = w
continue
}
// We can't delay the nil check past the next store.
break
}
}
// Issue a load which will fault if arg is nil.
p := gc.Prog(ppc64.AMOVB)
p.From.Type = obj.TYPE_MEM

2
test/nilptr3_ssa.go
View File

@ -1,5 +1,5 @@
// errorcheck -0 -d=nil
// +build amd64 arm amd64p32 386 arm64 mips64 mips64le
// +build amd64 arm amd64p32 386 arm64 mips64 mips64le ppc64le
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style