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cmd/compile: interleave devirtualization and inlining

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This CL interleaves devirtualization and inlining, so that
devirtualized calls can be inlined.

Fixes #52193.

Change-Id: I681e7c55bdb90ebf6df315d334e7a58f05110d9c
Reviewed-on: https://go-review.googlesource.com/c/go/+/528321
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Bypass: Matthew Dempsky <mdempsky@google.com>
This commit is contained in:
Matthew Dempsky 2023-11-18 20:16:47 -08:00 committed by Gopher Robot
parent ee6b34797b
commit 4a90cdb03d
9 changed files with 265 additions and 207 deletions
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18
src/cmd/compile/internal/devirtualize/devirtualize.go
View File

@ -18,22 +18,9 @@ import (
"cmd/compile/internal/types"
)
// Static devirtualizes calls within fn where possible when the concrete callee
// StaticCall devirtualizes the given call if possible when the concrete callee
// is available statically.
func Static(fn *ir.Func) {
ir.CurFunc = fn
ir.VisitList(fn.Body, func(n ir.Node) {
switch n := n.(type) {
case *ir.CallExpr:
staticCall(n)
}
})
}
// staticCall devirtualizes the given call if possible when the concrete callee
// is available statically.
func staticCall(call *ir.CallExpr) {
func StaticCall(call *ir.CallExpr) {
// For promoted methods (including value-receiver methods promoted
// to pointer-receivers), the interface method wrapper may contain
// expressions that can panic (e.g., ODEREF, ODOTPTR,
@ -51,6 +38,7 @@ func staticCall(call *ir.CallExpr) {
if call.Op() != ir.OCALLINTER {
return
}
sel := call.Fun.(*ir.SelectorExpr)
r := ir.StaticValue(sel.X)
if r.Op() != ir.OCONVIFACE {

25
src/cmd/compile/internal/gc/main.go
View File

@ -9,10 +9,10 @@ import (
"bytes"
"cmd/compile/internal/base"
"cmd/compile/internal/coverage"
"cmd/compile/internal/devirtualize"
"cmd/compile/internal/dwarfgen"
"cmd/compile/internal/escape"
"cmd/compile/internal/inline"
"cmd/compile/internal/inline/interleaved"
"cmd/compile/internal/ir"
"cmd/compile/internal/logopt"
"cmd/compile/internal/loopvar"
@ -224,30 +224,15 @@ func Main(archInit func(*ssagen.ArchInfo)) {
}
}
base.Timer.Start("fe", "pgo-devirtualization")
if profile != nil && base.Debug.PGODevirtualize > 0 {
// TODO(prattmic): No need to use bottom-up visit order. This
// is mirroring the PGO IRGraph visit order, which also need
// not be bottom-up.
ir.VisitFuncsBottomUp(typecheck.Target.Funcs, func(list []*ir.Func, recursive bool) {
for _, fn := range list {
devirtualize.ProfileGuided(fn, profile)
}
})
ir.CurFunc = nil
}
// Interleaved devirtualization and inlining.
base.Timer.Start("fe", "devirtualize-and-inline")
interleaved.DevirtualizeAndInlinePackage(typecheck.Target, profile)
// Inlining
base.Timer.Start("fe", "inlining")
if base.Flag.LowerL != 0 {
inline.InlinePackage(profile)
}
noder.MakeWrappers(typecheck.Target) // must happen after inlining
// Devirtualize and get variable capture right in for loops
// Get variable capture right in for loops.
var transformed []loopvar.VarAndLoop
for _, fn := range typecheck.Target.Funcs {
devirtualize.Static(fn)
transformed = append(transformed, loopvar.ForCapture(fn)...)
}
ir.CurFunc = nil

242
src/cmd/compile/internal/inline/inl.go
View File

@ -76,8 +76,8 @@ var (
inlineHotMaxBudget int32 = 2000
)
// pgoInlinePrologue records the hot callsites from ir-graph.
func pgoInlinePrologue(p *pgo.Profile, funcs []*ir.Func) {
// PGOInlinePrologue records the hot callsites from ir-graph.
func PGOInlinePrologue(p *pgo.Profile, funcs []*ir.Func) {
if base.Debug.PGOInlineCDFThreshold != "" {
if s, err := strconv.ParseFloat(base.Debug.PGOInlineCDFThreshold, 64); err == nil && s >= 0 && s <= 100 {
inlineCDFHotCallSiteThresholdPercent = s
@ -134,79 +134,52 @@ func hotNodesFromCDF(p *pgo.Profile) (float64, []pgo.NamedCallEdge) {
return 0, p.NamedEdgeMap.ByWeight
}
// InlinePackage finds functions that can be inlined and clones them before walk expands them.
func InlinePackage(p *pgo.Profile) {
if base.Debug.PGOInline == 0 {
p = nil
// CanInlineFuncs computes whether a batch of functions are inlinable.
func CanInlineFuncs(funcs []*ir.Func, profile *pgo.Profile) {
if profile != nil {
PGOInlinePrologue(profile, funcs)
}
inlheur.SetupScoreAdjustments()
InlineDecls(p, typecheck.Target.Funcs, true)
// Perform a garbage collection of hidden closures functions that
// are no longer reachable from top-level functions following
// inlining. See #59404 and #59638 for more context.
garbageCollectUnreferencedHiddenClosures()
if base.Debug.DumpInlFuncProps != "" {
inlheur.DumpFuncProps(nil, base.Debug.DumpInlFuncProps)
}
if inlheur.Enabled() {
postProcessCallSites(p)
inlheur.TearDown()
}
ir.VisitFuncsBottomUp(funcs, func(list []*ir.Func, recursive bool) {
CanInlineSCC(list, recursive, profile)
})
}
// InlineDecls applies inlining to the given batch of declarations.
func InlineDecls(p *pgo.Profile, funcs []*ir.Func, doInline bool) {
if p != nil {
pgoInlinePrologue(p, funcs)
// CanInlineSCC computes the inlinability of functions within an SCC
// (strongly connected component).
//
// CanInlineSCC is designed to be used by ir.VisitFuncsBottomUp
// callbacks.
func CanInlineSCC(funcs []*ir.Func, recursive bool, profile *pgo.Profile) {
if base.Flag.LowerL == 0 {
return
}
doCanInline := func(n *ir.Func, recursive bool, numfns int) {
numfns := numNonClosures(funcs)
for _, fn := range funcs {
if !recursive || numfns > 1 {
// We allow inlining if there is no
// recursion, or the recursion cycle is
// across more than one function.
CanInline(n, p)
CanInline(fn, profile)
} else {
if base.Flag.LowerM > 1 && n.OClosure == nil {
fmt.Printf("%v: cannot inline %v: recursive\n", ir.Line(n), n.Nname)
if base.Flag.LowerM > 1 && fn.OClosure == nil {
fmt.Printf("%v: cannot inline %v: recursive\n", ir.Line(fn), fn.Nname)
}
}
if inlheur.Enabled() {
analyzeFuncProps(n, p)
analyzeFuncProps(fn, profile)
}
}
ir.VisitFuncsBottomUp(funcs, func(list []*ir.Func, recursive bool) {
numfns := numNonClosures(list)
// We visit functions within an SCC in fairly arbitrary order,
// so by computing inlinability for all functions in the SCC
// before performing any inlining, the results are less
// sensitive to the order within the SCC (see #58905 for an
// example).
// First compute inlinability for all functions in the SCC ...
for _, n := range list {
doCanInline(n, recursive, numfns)
}
// ... then make a second pass to do inlining of calls.
if doInline {
for _, n := range list {
InlineCalls(n, p)
}
}
})
}
// garbageCollectUnreferencedHiddenClosures makes a pass over all the
// GarbageCollectUnreferencedHiddenClosures makes a pass over all the
// top-level (non-hidden-closure) functions looking for nested closure
// functions that are reachable, then sweeps through the Target.Decls
// list and marks any non-reachable hidden closure function as dead.
// See issues #59404 and #59638 for more context.
func garbageCollectUnreferencedHiddenClosures() {
func GarbageCollectUnreferencedHiddenClosures() {
liveFuncs := make(map[*ir.Func]bool)
@ -336,7 +309,7 @@ func CanInline(fn *ir.Func, profile *pgo.Profile) {
visitor := hairyVisitor{
curFunc: fn,
isBigFunc: isBigFunc(fn),
isBigFunc: IsBigFunc(fn),
budget: budget,
maxBudget: budget,
extraCallCost: cc,
@ -732,14 +705,16 @@ opSwitch:
// particular, to avoid breaking the existing inlinability regress
// tests), we need to compensate for this here.
//
// See also identical logic in isBigFunc.
if init := n.Rhs[0].Init(); len(init) == 1 {
if _, ok := init[0].(*ir.AssignListStmt); ok {
// 4 for each value, because each temporary variable now
// appears 3 times (DCL, LHS, RHS), plus an extra DCL node.
//
// 1 for the extra "tmp1, tmp2 = f()" assignment statement.
v.budget += 4*int32(len(n.Lhs)) + 1
// See also identical logic in IsBigFunc.
if len(n.Rhs) > 0 {
if init := n.Rhs[0].Init(); len(init) == 1 {
if _, ok := init[0].(*ir.AssignListStmt); ok {
// 4 for each value, because each temporary variable now
// appears 3 times (DCL, LHS, RHS), plus an extra DCL node.
//
// 1 for the extra "tmp1, tmp2 = f()" assignment statement.
v.budget += 4*int32(len(n.Lhs)) + 1
}
}
}
@ -771,12 +746,15 @@ opSwitch:
return ir.DoChildren(n, v.do)
}
func isBigFunc(fn *ir.Func) bool {
// IsBigFunc reports whether fn is a "big" function.
//
// Note: The criteria for "big" is heuristic and subject to change.
func IsBigFunc(fn *ir.Func) bool {
budget := inlineBigFunctionNodes
return ir.Any(fn, func(n ir.Node) bool {
// See logic in hairyVisitor.doNode, explaining unified IR's
// handling of "a, b = f()" assignments.
if n, ok := n.(*ir.AssignListStmt); ok && n.Op() == ir.OAS2 {
if n, ok := n.(*ir.AssignListStmt); ok && n.Op() == ir.OAS2 && len(n.Rhs) > 0 {
if init := n.Rhs[0].Init(); len(init) == 1 {
if _, ok := init[0].(*ir.AssignListStmt); ok {
budget += 4*len(n.Lhs) + 1
@ -789,109 +767,40 @@ func isBigFunc(fn *ir.Func) bool {
})
}
// 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, profile *pgo.Profile) {
if inlheur.Enabled() && !fn.Wrapper() {
inlheur.ScoreCalls(fn)
defer inlheur.ScoreCallsCleanup()
// TryInlineCall returns an inlined call expression for call, or nil
// if inlining is not possible.
func TryInlineCall(callerfn *ir.Func, call *ir.CallExpr, bigCaller bool, profile *pgo.Profile) *ir.InlinedCallExpr {
if base.Flag.LowerL == 0 {
return nil
}
if base.Debug.DumpInlFuncProps != "" && !fn.Wrapper() {
inlheur.DumpFuncProps(fn, base.Debug.DumpInlFuncProps)
if call.Op() != ir.OCALLFUNC {
return nil
}
savefn := ir.CurFunc
ir.CurFunc = fn
bigCaller := isBigFunc(fn)
if bigCaller && base.Flag.LowerM > 1 {
fmt.Printf("%v: function %v considered 'big'; reducing max cost of inlinees\n", ir.Line(fn), fn)
}
var inlCalls []*ir.InlinedCallExpr
var edit func(ir.Node) ir.Node
edit = func(n ir.Node) ir.Node {
return inlnode(fn, n, bigCaller, &inlCalls, edit, profile)
}
ir.EditChildren(fn, edit)
// If we inlined any calls, we want to recursively visit their
// bodies for further inlining. However, we need to wait until
// *after* the original function body has been expanded, or else
// inlCallee can have false positives (e.g., #54632).
for len(inlCalls) > 0 {
call := inlCalls[0]
inlCalls = inlCalls[1:]
ir.EditChildren(call, edit)
if call.GoDefer || call.NoInline {
return nil
}
ir.CurFunc = savefn
}
// inlnode recurses over the tree to find inlineable calls, which will
// be turned into OINLCALLs by mkinlcall. When the recursion comes
// back up will examine left, right, list, rlist, ninit, ntest, nincr,
// nbody and nelse and use one of the 4 inlconv/glue functions above
// to turn the OINLCALL into an expression, a statement, or patch it
// in to this nodes list or rlist as appropriate.
// NOTE it makes no sense to pass the glue functions down the
// recursion to the level where the OINLCALL gets created because they
// have to edit /this/ n, so you'd have to push that one down as well,
// but then you may as well do it here. so this is cleaner and
// shorter and less complicated.
// The result of inlnode MUST be assigned back to n, e.g.
//
// n.Left = inlnode(n.Left)
func inlnode(callerfn *ir.Func, n ir.Node, bigCaller bool, inlCalls *[]*ir.InlinedCallExpr, edit func(ir.Node) ir.Node, profile *pgo.Profile) ir.Node {
if n == nil {
return n
}
switch n.Op() {
case ir.OTAILCALL:
n := n.(*ir.TailCallStmt)
n.Call.NoInline = true // Not inline a tail call for now. Maybe we could inline it just like RETURN fn(arg)?
case ir.OCALLFUNC:
n := n.(*ir.CallExpr)
if n.Fun.Op() == ir.OMETHEXPR {
// Prevent inlining some reflect.Value methods when using checkptr,
// even when package reflect was compiled without it (#35073).
if meth := ir.MethodExprName(n.Fun); meth != nil {
s := meth.Sym()
if base.Debug.Checkptr != 0 {
switch types.ReflectSymName(s) {
case "Value.UnsafeAddr", "Value.Pointer":
n.NoInline = true
}
}
// Prevent inlining some reflect.Value methods when using checkptr,
// even when package reflect was compiled without it (#35073).
if base.Debug.Checkptr != 0 && call.Fun.Op() == ir.OMETHEXPR {
if method := ir.MethodExprName(call.Fun); method != nil {
switch types.ReflectSymName(method.Sym()) {
case "Value.UnsafeAddr", "Value.Pointer":
return nil
}
}
}
lno := ir.SetPos(n)
ir.EditChildren(n, edit)
// with all the branches out of the way, it is now time to
// transmogrify this node itself unless inhibited by the
// switch at the top of this function.
switch n.Op() {
case ir.OCALLFUNC:
call := n.(*ir.CallExpr)
if call.GoDefer || call.NoInline {
break
}
if base.Flag.LowerM > 3 {
fmt.Printf("%v:call to func %+v\n", ir.Line(n), call.Fun)
}
if ir.IsIntrinsicCall(call) {
break
}
if fn := inlCallee(callerfn, call.Fun, profile); fn != nil && typecheck.HaveInlineBody(fn) {
n = mkinlcall(callerfn, call, fn, bigCaller, inlCalls)
}
if base.Flag.LowerM > 3 {
fmt.Printf("%v:call to func %+v\n", ir.Line(call), call.Fun)
}
base.Pos = lno
return n
if ir.IsIntrinsicCall(call) {
return nil
}
if fn := inlCallee(callerfn, call.Fun, profile); fn != nil && typecheck.HaveInlineBody(fn) {
return mkinlcall(callerfn, call, fn, bigCaller)
}
return nil
}
// inlCallee takes a function-typed expression and returns the underlying function ONAME
@ -1082,17 +991,16 @@ func canInlineCallExpr(callerfn *ir.Func, n *ir.CallExpr, callee *ir.Func, bigCa
return true
}
// If n is a OCALLFUNC node, and fn is an ONAME node for a
// function with an inlinable body, return an OINLCALL node that can replace n.
// The returned node's Ninit has the parameter assignments, the Nbody is the
// inlined function body, and (List, Rlist) contain the (input, output)
// parameters.
// mkinlcall returns an OINLCALL node that can replace OCALLFUNC n, or
// nil if it cannot be inlined. callerfn is the function that contains
// n, and fn is the function being called.
//
// The result of mkinlcall MUST be assigned back to n, e.g.
//
// n.Left = mkinlcall(n.Left, fn, isddd)
func mkinlcall(callerfn *ir.Func, n *ir.CallExpr, fn *ir.Func, bigCaller bool, inlCalls *[]*ir.InlinedCallExpr) ir.Node {
func mkinlcall(callerfn *ir.Func, n *ir.CallExpr, fn *ir.Func, bigCaller bool) *ir.InlinedCallExpr {
if !canInlineCallExpr(callerfn, n, fn, bigCaller, true) {
return n
return nil
}
typecheck.AssertFixedCall(n)
@ -1170,8 +1078,6 @@ func mkinlcall(callerfn *ir.Func, n *ir.CallExpr, fn *ir.Func, bigCaller bool, i
inlheur.UpdateCallsiteTable(callerfn, n, res)
}
*inlCalls = append(*inlCalls, res)
return res
}
@ -1275,7 +1181,7 @@ func isAtomicCoverageCounterUpdate(cn *ir.CallExpr) bool {
return v
}
func postProcessCallSites(profile *pgo.Profile) {
func PostProcessCallSites(profile *pgo.Profile) {
if base.Debug.DumpInlCallSiteScores != 0 {
budgetCallback := func(fn *ir.Func, prof *pgo.Profile) (int32, bool) {
v := inlineBudget(fn, prof, false, false)

132
src/cmd/compile/internal/inline/interleaved/interleaved.go Normal file
View File

@ -0,0 +1,132 @@
// Copyright 2023 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package interleaved implements the interleaved devirtualization and
// inlining pass.
package interleaved
import (
"cmd/compile/internal/base"
"cmd/compile/internal/devirtualize"
"cmd/compile/internal/inline"
"cmd/compile/internal/inline/inlheur"
"cmd/compile/internal/ir"
"cmd/compile/internal/pgo"
"cmd/compile/internal/typecheck"
"fmt"
)
// DevirtualizeAndInlinePackage interleaves devirtualization and inlining on
// all functions within pkg.
func DevirtualizeAndInlinePackage(pkg *ir.Package, profile *pgo.Profile) {
if profile != nil && base.Debug.PGODevirtualize > 0 {
// TODO(mdempsky): Integrate into DevirtualizeAndInlineFunc below.
ir.VisitFuncsBottomUp(typecheck.Target.Funcs, func(list []*ir.Func, recursive bool) {
for _, fn := range list {
devirtualize.ProfileGuided(fn, profile)
}
})
ir.CurFunc = nil
}
if base.Flag.LowerL != 0 {
inlheur.SetupScoreAdjustments()
}
var inlProfile *pgo.Profile // copy of profile for inlining
if base.Debug.PGOInline != 0 {
inlProfile = profile
}
if inlProfile != nil {
inline.PGOInlinePrologue(inlProfile, pkg.Funcs)
}
ir.VisitFuncsBottomUp(pkg.Funcs, func(funcs []*ir.Func, recursive bool) {
// We visit functions within an SCC in fairly arbitrary order,
// so by computing inlinability for all functions in the SCC
// before performing any inlining, the results are less
// sensitive to the order within the SCC (see #58905 for an
// example).
// First compute inlinability for all functions in the SCC ...
inline.CanInlineSCC(funcs, recursive, inlProfile)
// ... then make a second pass to do devirtualization and inlining
// of calls.
for _, fn := range funcs {
DevirtualizeAndInlineFunc(fn, inlProfile)
}
})
if base.Flag.LowerL != 0 {
// Perform a garbage collection of hidden closures functions that
// are no longer reachable from top-level functions following
// inlining. See #59404 and #59638 for more context.
inline.GarbageCollectUnreferencedHiddenClosures()
if base.Debug.DumpInlFuncProps != "" {
inlheur.DumpFuncProps(nil, base.Debug.DumpInlFuncProps)
}
if inlheur.Enabled() {
inline.PostProcessCallSites(inlProfile)
inlheur.TearDown()
}
}
}
// DevirtualizeAndInlineFunc interleaves devirtualization and inlining
// on a single function.
func DevirtualizeAndInlineFunc(fn *ir.Func, profile *pgo.Profile) {
ir.WithFunc(fn, func() {
if base.Flag.LowerL != 0 {
if inlheur.Enabled() && !fn.Wrapper() {
inlheur.ScoreCalls(fn)
defer inlheur.ScoreCallsCleanup()
}
if base.Debug.DumpInlFuncProps != "" && !fn.Wrapper() {
inlheur.DumpFuncProps(fn, base.Debug.DumpInlFuncProps)
}
}
bigCaller := base.Flag.LowerL != 0 && inline.IsBigFunc(fn)
if bigCaller && base.Flag.LowerM > 1 {
fmt.Printf("%v: function %v considered 'big'; reducing max cost of inlinees\n", ir.Line(fn), fn)
}
// Walk fn's body and apply devirtualization and inlining.
var inlCalls []*ir.InlinedCallExpr
var edit func(ir.Node) ir.Node
edit = func(n ir.Node) ir.Node {
switch n := n.(type) {
case *ir.TailCallStmt:
n.Call.NoInline = true // can't inline yet
}
ir.EditChildren(n, edit)
if call, ok := n.(*ir.CallExpr); ok {
devirtualize.StaticCall(call)
if inlCall := inline.TryInlineCall(fn, call, bigCaller, profile); inlCall != nil {
inlCalls = append(inlCalls, inlCall)
n = inlCall
}
}
return n
}
ir.EditChildren(fn, edit)
// If we inlined any calls, we want to recursively visit their
// bodies for further devirtualization and inlining. However, we
// need to wait until *after* the original function body has been
// expanded, or else inlCallee can have false positives (e.g.,
// #54632).
for len(inlCalls) > 0 {
call := inlCalls[0]
inlCalls = inlCalls[1:]
ir.EditChildren(call, edit)
}
})
}

3
src/cmd/compile/internal/noder/reader.go
View File

@ -15,6 +15,7 @@ import (
"cmd/compile/internal/base"
"cmd/compile/internal/dwarfgen"
"cmd/compile/internal/inline"
"cmd/compile/internal/inline/interleaved"
"cmd/compile/internal/ir"
"cmd/compile/internal/objw"
"cmd/compile/internal/reflectdata"
@ -3794,7 +3795,7 @@ func finishWrapperFunc(fn *ir.Func, target *ir.Package) {
// We generate wrappers after the global inlining pass,
// so we're responsible for applying inlining ourselves here.
// TODO(prattmic): plumb PGO.
inline.InlineCalls(fn, nil)
interleaved.DevirtualizeAndInlineFunc(fn, nil)
// The body of wrapper function after inlining may reveal new ir.OMETHVALUE node,
// we don't know whether wrapper function has been generated for it or not, so

2
src/cmd/compile/internal/noder/unified.go
View File

@ -280,7 +280,7 @@ func readBodies(target *ir.Package, duringInlining bool) {
oldLowerM := base.Flag.LowerM
base.Flag.LowerM = 0
inline.InlineDecls(nil, inlDecls, false)
inline.CanInlineFuncs(inlDecls, nil)
base.Flag.LowerM = oldLowerM
for _, fn := range inlDecls {

2
test/fixedbugs/issue42284.dir/a.go
View File

@ -20,7 +20,7 @@ func F(i I) I { // ERROR "can inline F" "leaking param: i to result ~r0 level=0"
func g() {
h := E() // ERROR "inlining call to E" "T\(0\) does not escape"
h.M() // ERROR "devirtualizing h.M to T"
h.M() // ERROR "devirtualizing h.M to T" "inlining call to T.M"
// BAD: T(0) could be stack allocated.
i := F(T(0)) // ERROR "inlining call to F" "T\(0\) escapes to heap"

2
test/fixedbugs/issue42284.dir/b.go
View File

@ -8,7 +8,7 @@ import "./a"
func g() {
h := a.E() // ERROR "inlining call to a.E" "T\(0\) does not escape"
h.M() // ERROR "devirtualizing h.M to a.T"
h.M() // ERROR "devirtualizing h.M to a.T" "inlining call to a.T.M"
// BAD: T(0) could be stack allocated.
i := a.F(a.T(0)) // ERROR "inlining call to a.F" "a.T\(0\) escapes to heap"

46
test/fixedbugs/issue52193.go Normal file
View File

@ -0,0 +1,46 @@
// errorcheck -0 -m
// Copyright 2023 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package p
import (
"crypto/ecdh"
"crypto/rand"
)
func F(peerShare []byte) ([]byte, error) { // ERROR "leaking param: peerShare"
p256 := ecdh.P256() // ERROR "inlining call to ecdh.P256"
ourKey, err := p256.GenerateKey(rand.Reader) // ERROR "devirtualizing p256.GenerateKey" "inlining call to ecdh.*GenerateKey"
if err != nil {
return nil, err
}
peerPublic, err := p256.NewPublicKey(peerShare) // ERROR "devirtualizing p256.NewPublicKey" "inlining call to ecdh.*NewPublicKey"
if err != nil {
return nil, err
}
return ourKey.ECDH(peerPublic)
}
// Test that inlining doesn't break if devirtualization exposes a new
// inlinable callee.
func f() { // ERROR "can inline f"
var i interface{ m() } = T(0) // ERROR "T\(0\) does not escape"
i.m() // ERROR "devirtualizing i.m"
}
type T int
func (T) m() { // ERROR "can inline T.m"
if never {
f() // ERROR "inlining call to f" "devirtualizing i.m" "T\(0\) does not escape"
}
}
var never bool