Stowage/go
2
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-12-08 06:10:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

cmd/compile/internal/pgo: remove most global state

Browse source 
Since pgo is a new package, it is reasonably straightforward to
encapsulate its state into a non-global object that we pass around,
which will help keep it isolated.

There are no functional changes in this CL, just packaging up the
globals into a new object.

There are two major pieces of cleanup remaining:

1. reflectdata and noder have separate InlineCalls calls for method
   wrappers. The Profile is not plumbed there yet, but this is not a
   regression as the globals were previously set only right around the
   main inlining pass in gc.Main.

2. pgo.ListOfHotCallSites is still global, as it will require more work
   to clean up. It is effectively a local variable in InlinePackage,
   except that it assumes that InlineCalls is immediately preceded by a
   CanInline call for the same function. This is not necessarily true
   due to the recursive nature of CanInline. This also means that some
   InlineCalls calls may be missing the list of hot callsites right now.

For #55022.

Change-Id: Ic1fe41f73df96861c65f8bfeecff89862b367290
Reviewed-on: https://go-review.googlesource.com/c/go/+/446303
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Michael Pratt <mpratt@google.com>
This commit is contained in:
Michael Pratt 2022-10-28 17:34:43 -04:00
parent 3848b44c75
commit 204be97d24
6 changed files with 190 additions and 175 deletions
Download patch file Download diff file Expand all files Collapse all files

64
src/cmd/compile/internal/inline/inl.go
View file

@ -75,8 +75,8 @@ var (
inlineHotMaxBudget int32 = 160
)
// InlinePrologue records the hot callsites from ir-graph.
func InlinePrologue() {
// pgoInlinePrologue records the hot callsites from ir-graph.
func pgoInlinePrologue(p *pgo.Profile) {
if s, err := strconv.ParseFloat(base.Debug.InlineHotFuncThreshold, 64); err == nil {
inlineHotFuncThresholdPercent = s
if base.Debug.PGOInline > 0 {
@ -98,14 +98,14 @@ func InlinePrologue() {
ir.VisitFuncsBottomUp(typecheck.Target.Decls, func(list []*ir.Func, recursive bool) {
for _, f := range list {
name := ir.PkgFuncName(f)
if n, ok := pgo.WeightedCG.IRNodes[name]; ok {
nodeweight := pgo.WeightInPercentage(n.Flat, pgo.GlobalTotalNodeWeight)
if n, ok := p.WeightedCG.IRNodes[name]; ok {
nodeweight := pgo.WeightInPercentage(n.Flat, p.TotalNodeWeight)
if nodeweight > inlineHotFuncThresholdPercent {
candHotNodeMap[n] = struct{}{}
}
for _, e := range pgo.WeightedCG.OutEdges[n] {
for _, e := range p.WeightedCG.OutEdges[n] {
if e.Weight != 0 {
edgeweightpercent := pgo.WeightInPercentage(e.Weight, pgo.GlobalTotalEdgeWeight)
edgeweightpercent := pgo.WeightInPercentage(e.Weight, p.TotalEdgeWeight)
if edgeweightpercent > inlineHotCallSiteThresholdPercent {
csi := pgo.CallSiteInfo{Line: e.CallSite, Caller: n.AST, Callee: e.Dst.AST}
if _, ok := candHotEdgeMap[csi]; !ok {
@ -119,29 +119,33 @@ func InlinePrologue() {
})
if base.Debug.PGOInline > 0 {
fmt.Printf("hot-cg before inline in dot format:")
pgo.PrintWeightedCallGraphDOT(inlineHotFuncThresholdPercent, inlineHotCallSiteThresholdPercent)
p.PrintWeightedCallGraphDOT(inlineHotFuncThresholdPercent, inlineHotCallSiteThresholdPercent)
}
}
// InlineEpilogue updates IRGraph after inlining.
func InlineEpilogue() {
// pgoInlineEpilogue updates IRGraph after inlining.
func pgoInlineEpilogue(p *pgo.Profile) {
if base.Debug.PGOInline > 0 {
ir.VisitFuncsBottomUp(typecheck.Target.Decls, func(list []*ir.Func, recursive bool) {
for _, f := range list {
name := ir.PkgFuncName(f)
if n, ok := pgo.WeightedCG.IRNodes[name]; ok {
pgo.RedirectEdges(n, inlinedCallSites)
if n, ok := p.WeightedCG.IRNodes[name]; ok {
p.RedirectEdges(n, inlinedCallSites)
}
}
})
// Print the call-graph after inlining. This is a debugging feature.
fmt.Printf("hot-cg after inline in dot:")
pgo.PrintWeightedCallGraphDOT(inlineHotFuncThresholdPercent, inlineHotCallSiteThresholdPercent)
p.PrintWeightedCallGraphDOT(inlineHotFuncThresholdPercent, inlineHotCallSiteThresholdPercent)
}
}
// InlinePackage finds functions that can be inlined and clones them before walk expands them.
func InlinePackage() {
func InlinePackage(p *pgo.Profile) {
if p != nil {
pgoInlinePrologue(p)
}
ir.VisitFuncsBottomUp(typecheck.Target.Decls, func(list []*ir.Func, recursive bool) {
numfns := numNonClosures(list)
for _, n := range list {
@ -149,21 +153,25 @@ func InlinePackage() {
// We allow inlining if there is no
// recursion, or the recursion cycle is
// across more than one function.
CanInline(n)
CanInline(n, p)
} else {
if base.Flag.LowerM > 1 {
fmt.Printf("%v: cannot inline %v: recursive\n", ir.Line(n), n.Nname)
}
}
InlineCalls(n)
InlineCalls(n, p)
}
})
if p != nil {
pgoInlineEpilogue(p)
}
}
// CanInline determines whether fn is inlineable.
// If so, CanInline saves copies of fn.Body and fn.Dcl in fn.Inl.
// fn and fn.Body will already have been typechecked.
func CanInline(fn *ir.Func) {
func CanInline(fn *ir.Func, profile *pgo.Profile) {
if fn.Nname == nil {
base.Fatalf("CanInline no nname %+v", fn)
}
@ -260,8 +268,8 @@ func CanInline(fn *ir.Func) {
// Update the budget for profile-guided inlining.
budget := int32(inlineMaxBudget)
if base.Flag.PgoProfile != "" && pgo.WeightedCG != nil {
if n, ok := pgo.WeightedCG.IRNodes[ir.PkgFuncName(fn)]; ok {
if profile != nil {
if n, ok := profile.WeightedCG.IRNodes[ir.PkgFuncName(fn)]; ok {
if _, ok := candHotNodeMap[n]; ok {
budget = int32(inlineHotMaxBudget)
if base.Debug.PGOInline > 0 {
@ -285,6 +293,7 @@ func CanInline(fn *ir.Func) {
budget: budget,
maxBudget: budget,
extraCallCost: cc,
profile: profile,
}
if visitor.tooHairy(fn) {
reason = visitor.reason
@ -352,6 +361,7 @@ type hairyVisitor struct {
extraCallCost int32
usedLocals ir.NameSet
do func(ir.Node) bool
profile *pgo.Profile
}
func (v *hairyVisitor) tooHairy(fn *ir.Func) bool {
@ -439,8 +449,8 @@ func (v *hairyVisitor) doNode(n ir.Node) bool {
}
// Determine if the callee edge is a for hot callee or not.
if base.Flag.PgoProfile != "" && pgo.WeightedCG != nil && v.curFunc != nil {
if fn := inlCallee(n.X); fn != nil && typecheck.HaveInlineBody(fn) {
if v.profile != nil && v.curFunc != nil {
if fn := inlCallee(n.X, v.profile); fn != nil && typecheck.HaveInlineBody(fn) {
line := int(base.Ctxt.InnermostPos(n.Pos()).RelLine())
csi := pgo.CallSiteInfo{Line: line, Caller: v.curFunc, Callee: fn}
if _, o := candHotEdgeMap[csi]; o {
@ -457,7 +467,7 @@ func (v *hairyVisitor) doNode(n ir.Node) bool {
break
}
if fn := inlCallee(n.X); fn != nil && typecheck.HaveInlineBody(fn) {
if fn := inlCallee(n.X, v.profile); fn != nil && typecheck.HaveInlineBody(fn) {
v.budget -= fn.Inl.Cost
break
}
@ -687,7 +697,7 @@ func inlcopy(n ir.Node) ir.Node {
// InlineCalls/inlnode walks fn's statements and expressions and substitutes any
// calls made to inlineable functions. This is the external entry point.
func InlineCalls(fn *ir.Func) {
func InlineCalls(fn *ir.Func, profile *pgo.Profile) {
savefn := ir.CurFunc
ir.CurFunc = fn
maxCost := int32(inlineMaxBudget)
@ -697,7 +707,7 @@ func InlineCalls(fn *ir.Func) {
var inlCalls []*ir.InlinedCallExpr
var edit func(ir.Node) ir.Node
edit = func(n ir.Node) ir.Node {
return inlnode(n, maxCost, &inlCalls, edit)
return inlnode(n, maxCost, &inlCalls, edit, profile)
}
ir.EditChildren(fn, edit)
@ -728,7 +738,7 @@ func InlineCalls(fn *ir.Func) {
// The result of inlnode MUST be assigned back to n, e.g.
//
// n.Left = inlnode(n.Left)
func inlnode(n ir.Node, maxCost int32, inlCalls *[]*ir.InlinedCallExpr, edit func(ir.Node) ir.Node) ir.Node {
func inlnode(n ir.Node, maxCost int32, inlCalls *[]*ir.InlinedCallExpr, edit func(ir.Node) ir.Node, profile *pgo.Profile) ir.Node {
if n == nil {
return n
}
@ -789,7 +799,7 @@ func inlnode(n ir.Node, maxCost int32, inlCalls *[]*ir.InlinedCallExpr, edit fun
if ir.IsIntrinsicCall(call) {
break
}
if fn := inlCallee(call.X); fn != nil && typecheck.HaveInlineBody(fn) {
if fn := inlCallee(call.X, profile); fn != nil && typecheck.HaveInlineBody(fn) {
n = mkinlcall(call, fn, maxCost, inlCalls, edit)
}
}
@ -801,7 +811,7 @@ func inlnode(n ir.Node, maxCost int32, inlCalls *[]*ir.InlinedCallExpr, edit fun
// inlCallee takes a function-typed expression and returns the underlying function ONAME
// that it refers to if statically known. Otherwise, it returns nil.
func inlCallee(fn ir.Node) *ir.Func {
func inlCallee(fn ir.Node, profile *pgo.Profile) *ir.Func {
fn = ir.StaticValue(fn)
switch fn.Op() {
case ir.OMETHEXPR:
@ -822,7 +832,7 @@ func inlCallee(fn ir.Node) *ir.Func {
case ir.OCLOSURE:
fn := fn.(*ir.ClosureExpr)
c := fn.Func
CanInline(c)
CanInline(c, profile)
return c
}
return nil