cmd/internal/gc: cache ProgInfo in Prog
The ProgInfo is loaded many times during each analysis pass.
Load it once at the beginning (in Flowstart if using that, or explicitly,
as in plive.go) and then refer to the cached copy.
Removes many calls to proginfo.
Makes Prog a little bigger, but the previous CL more than compensates.
Change-Id: If90a12fc6729878fdae10444f9c3bedc8d85026e
Reviewed-on: https://go-review.googlesource.com/7745
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
diff --git a/src/cmd/internal/gc/popt.go b/src/cmd/internal/gc/popt.go
index 9070007..8dcd1df 100644
--- a/src/cmd/internal/gc/popt.go
+++ b/src/cmd/internal/gc/popt.go
@@ -355,15 +355,13 @@
var flowmark int
func Flowstart(firstp *obj.Prog, newData func() interface{}) *Graph {
- var info ProgInfo
-
// Count and mark instructions to annotate.
nf := 0
for p := firstp; p != nil; p = p.Link {
p.Opt = nil // should be already, but just in case
- info = Thearch.Proginfo(p)
- if info.Flags&Skip != 0 {
+ Thearch.Proginfo(p)
+ if p.Info.Flags&Skip != 0 {
continue
}
p.Opt = &flowmark
@@ -409,8 +407,7 @@
var p *obj.Prog
for f := start; f != nil; f = f.Link {
p = f.Prog
- info = Thearch.Proginfo(p)
- if info.Flags&Break == 0 {
+ if p.Info.Flags&Break == 0 {
f1 = f.Link
f.S1 = f1
f1.P1 = f
@@ -442,6 +439,7 @@
func Flowend(graph *Graph) {
for f := graph.Start; f != nil; f = f.Link {
+ f.Prog.Info.Flags = 0 // drop cached proginfo
f.Prog.Opt = nil
}
}
@@ -714,12 +712,8 @@
// We assume that the earliest reference to a temporary is its definition.
// This is not true of variables in general but our temporaries are all
// single-use (that's why we have so many!).
- var p *obj.Prog
- var info ProgInfo
for f := g.Start; f != nil; f = f.Link {
- p = f.Prog
- info = Thearch.Proginfo(p)
-
+ p := f.Prog
if p.From.Node != nil && ((p.From.Node).(*Node)).Opt != nil && p.To.Node != nil && ((p.To.Node).(*Node)).Opt != nil {
Fatal("double node %v", p)
}
@@ -740,7 +734,7 @@
}
f.Data = v.use
v.use = f
- if n == p.From.Node && (info.Flags&LeftAddr != 0) {
+ if n == p.From.Node && (p.Info.Flags&LeftAddr != 0) {
v.addr = 1
}
}
@@ -753,9 +747,6 @@
nkill := 0
// Special case.
- var p1 *obj.Prog
- var info1 ProgInfo
- var f *Flow
for i := 0; i < len(var_); i++ {
v = &var_[i]
if v.addr != 0 {
@@ -763,11 +754,10 @@
}
// Used in only one instruction, which had better be a write.
- f = v.use
+ f := v.use
if f != nil && f.Data.(*Flow) == nil {
- p = f.Prog
- info = Thearch.Proginfo(p)
- if p.To.Node == v.node && (info.Flags&RightWrite != 0) && info.Flags&RightRead == 0 {
+ p := f.Prog
+ if p.To.Node == v.node && (p.Info.Flags&RightWrite != 0) && p.Info.Flags&RightRead == 0 {
p.As = obj.ANOP
p.To = obj.Addr{}
v.removed = 1
@@ -785,14 +775,12 @@
// no jumps to the next instruction. Happens mainly in 386 compiler.
f = v.use
if f != nil && f.Link == f.Data.(*Flow) && (f.Data.(*Flow)).Data.(*Flow) == nil && Uniqp(f.Link) == f {
- p = f.Prog
- info = Thearch.Proginfo(p)
- p1 = f.Link.Prog
- info1 = Thearch.Proginfo(p1)
+ p := f.Prog
+ p1 := f.Link.Prog
const (
SizeAny = SizeB | SizeW | SizeL | SizeQ | SizeF | SizeD
)
- if p.From.Node == v.node && p1.To.Node == v.node && (info.Flags&Move != 0) && (info.Flags|info1.Flags)&(LeftAddr|RightAddr) == 0 && info.Flags&SizeAny == info1.Flags&SizeAny {
+ if p.From.Node == v.node && p1.To.Node == v.node && (p.Info.Flags&Move != 0) && (p.Info.Flags|p1.Info.Flags)&(LeftAddr|RightAddr) == 0 && p.Info.Flags&SizeAny == p1.Info.Flags&SizeAny {
p1.From = p.From
Thearch.Excise(f)
v.removed = 1
@@ -814,12 +802,12 @@
for i := 0; i < len(var_); i++ {
v = &var_[i]
gen++
- for f = v.use; f != nil; f = f.Data.(*Flow) {
+ for f := v.use; f != nil; f = f.Data.(*Flow) {
mergewalk(v, f, uint32(gen))
}
if v.addr != 0 {
gen++
- for f = v.use; f != nil; f = f.Data.(*Flow) {
+ for f := v.use; f != nil; f = f.Data.(*Flow) {
varkillwalk(v, f, uint32(gen))
}
}
@@ -935,7 +923,7 @@
// Update node references to use merged temporaries.
for f := g.Start; f != nil; f = f.Link {
- p = f.Prog
+ p := f.Prog
n, _ = p.From.Node.(*Node)
if n != nil {
v, _ = n.Opt.(*TempVar)
@@ -1109,13 +1097,9 @@
}
func nilwalkback(fcheck *Flow) {
- var p *obj.Prog
- var info ProgInfo
-
for f := fcheck; f != nil; f = Uniqp(f) {
- p = f.Prog
- info = Thearch.Proginfo(p)
- if (info.Flags&RightWrite != 0) && Thearch.Sameaddr(&p.To, &fcheck.Prog.From) {
+ p := f.Prog
+ if (p.Info.Flags&RightWrite != 0) && Thearch.Sameaddr(&p.To, &fcheck.Prog.From) {
// Found initialization of value we're checking for nil.
// without first finding the check, so this one is unchecked.
return
@@ -1146,8 +1130,7 @@
if(f1 != fcheck && p->as == ACHECKNIL && thearch.sameaddr(&p->from, &fcheck->prog->from))
break;
- thearch.proginfo(&info, p);
- if((info.flags & RightWrite) && thearch.sameaddr(&p->to, &fcheck->prog->from)) {
+ if((p.Info.flags & RightWrite) && thearch.sameaddr(&p->to, &fcheck->prog->from)) {
// Found initialization of value we're checking for nil.
// without first finding the check, so this one is unchecked.
fcheck->kill = 0;
@@ -1168,10 +1151,8 @@
for(f2 = f->p2; f2 != nil; f2 = f2->p2link)
nilwalkback(fcheck, f2, gen);
*/
-func nilwalkfwd(fcheck *Flow) {
- var p *obj.Prog
- var info ProgInfo
+func nilwalkfwd(fcheck *Flow) {
// If the path down from rcheck dereferences the address
// (possibly with a small offset) before writing to memory
// and before any subsequent checks, it's okay to wait for
@@ -1179,18 +1160,16 @@
// avoid problems like:
// _ = *x // should panic
// for {} // no writes but infinite loop may be considered visible
+
var last *Flow
-
for f := Uniqs(fcheck); f != nil; f = Uniqs(f) {
- p = f.Prog
- info = Thearch.Proginfo(p)
-
- if (info.Flags&LeftRead != 0) && Thearch.Smallindir(&p.From, &fcheck.Prog.From) {
+ p := f.Prog
+ if (p.Info.Flags&LeftRead != 0) && Thearch.Smallindir(&p.From, &fcheck.Prog.From) {
fcheck.Data = &killed
return
}
- if (info.Flags&(RightRead|RightWrite) != 0) && Thearch.Smallindir(&p.To, &fcheck.Prog.From) {
+ if (p.Info.Flags&(RightRead|RightWrite) != 0) && Thearch.Smallindir(&p.To, &fcheck.Prog.From) {
fcheck.Data = &killed
return
}
@@ -1201,12 +1180,12 @@
}
// Stop if value is lost.
- if (info.Flags&RightWrite != 0) && Thearch.Sameaddr(&p.To, &fcheck.Prog.From) {
+ if (p.Info.Flags&RightWrite != 0) && Thearch.Sameaddr(&p.To, &fcheck.Prog.From) {
return
}
// Stop if memory write.
- if (info.Flags&RightWrite != 0) && !Thearch.Regtyp(&p.To) {
+ if (p.Info.Flags&RightWrite != 0) && !Thearch.Regtyp(&p.To) {
return
}
