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cmd/6g: make proginfo register bits constants

Also replace proginfo call with cheaper calls where only flags are needed.

Change-Id: Ib6e5c12bd8752b87c0d8bcf22fa9e25e04a7941f
Reviewed-on: https://go-review.googlesource.com/7630
Reviewed-by: Rob Pike <r@golang.org>
This commit is contained in:
Russ Cox 2015-03-10 15:18:10 -04:00
parent 00b3b40b07
commit 1fdd1d181b
3 changed files with 30 additions and 19 deletions

View File

@ -45,14 +45,12 @@ const (
// do we need the carry bit // do we need the carry bit
func needc(p *obj.Prog) bool { func needc(p *obj.Prog) bool {
var info gc.ProgInfo
for p != nil { for p != nil {
info = proginfo(p) flags := progcarryflags(p)
if info.Flags&gc.UseCarry != 0 { if flags&gc.UseCarry != 0 {
return true return true
} }
if info.Flags&(gc.SetCarry|gc.KillCarry) != 0 { if flags&(gc.SetCarry|gc.KillCarry) != 0 {
return false return false
} }
p = p.Link p = p.Link
@ -508,15 +506,12 @@ func regconsttyp(a *obj.Addr) bool {
// is reg guaranteed to be truncated by a previous L instruction? // is reg guaranteed to be truncated by a previous L instruction?
func prevl(r0 *gc.Flow, reg int) bool { func prevl(r0 *gc.Flow, reg int) bool {
var p *obj.Prog
var info gc.ProgInfo
for r := (*gc.Flow)(gc.Uniqp(r0)); r != nil; r = gc.Uniqp(r) { for r := (*gc.Flow)(gc.Uniqp(r0)); r != nil; r = gc.Uniqp(r) {
p = r.Prog p := r.Prog
if p.To.Type == obj.TYPE_REG && int(p.To.Reg) == reg { if p.To.Type == obj.TYPE_REG && int(p.To.Reg) == reg {
info = proginfo(p) flags := progflags(p)
if info.Flags&gc.RightWrite != 0 { if flags&gc.RightWrite != 0 {
if info.Flags&gc.SizeL != 0 { if flags&gc.SizeL != 0 {
return true return true
} }
return false return false

View File

@ -10,13 +10,7 @@ import (
"cmd/internal/obj/x86" "cmd/internal/obj/x86"
) )
var ( const (
AX = RtoB(x86.REG_AX)
BX = RtoB(x86.REG_BX)
CX = RtoB(x86.REG_CX)
DX = RtoB(x86.REG_DX)
DI = RtoB(x86.REG_DI)
SI = RtoB(x86.REG_SI)
LeftRdwr uint32 = gc.LeftRead | gc.LeftWrite LeftRdwr uint32 = gc.LeftRead | gc.LeftWrite
RightRdwr uint32 = gc.RightRead | gc.RightWrite RightRdwr uint32 = gc.RightRead | gc.RightWrite
) )
@ -237,6 +231,18 @@ var progtable = [x86.ALAST]gc.ProgInfo{
x86.AXORW: gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0}, x86.AXORW: gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
} }
func progflags(p *obj.Prog) uint32 {
flags := progtable[p.As].Flags
if flags&gc.ImulAXDX != 0 && p.To.Type != obj.TYPE_NONE {
flags |= RightRdwr
}
return flags
}
func progcarryflags(p *obj.Prog) uint32 {
return progtable[p.As].Flags
}
func proginfo(p *obj.Prog) (info gc.ProgInfo) { func proginfo(p *obj.Prog) (info gc.ProgInfo) {
info = progtable[p.As] info = progtable[p.As]
if info.Flags == 0 { if info.Flags == 0 {

View File

@ -98,6 +98,16 @@ func doregbits(r int) uint64 {
return b return b
} }
// For ProgInfo.
const (
AX = 1 << (x86.REG_AX - x86.REG_AX)
BX = 1 << (x86.REG_BX - x86.REG_AX)
CX = 1 << (x86.REG_CX - x86.REG_AX)
DX = 1 << (x86.REG_DX - x86.REG_AX)
DI = 1 << (x86.REG_DI - x86.REG_AX)
SI = 1 << (x86.REG_SI - x86.REG_AX)
)
func RtoB(r int) uint64 { func RtoB(r int) uint64 {
if r < x86.REG_AX || r > x86.REG_R15 { if r < x86.REG_AX || r > x86.REG_R15 {
return 0 return 0