go/test/inline_unified.go
Matthew Dempsky 6a801d3082 cmd/compile/internal/noder: fix inlined function literal positions
When inlining function calls, we rewrite the position information on
all of the nodes to keep track of the inlining context. This is
necessary so that at runtime, we can synthesize additional stack
frames so that the inlining is transparent to the user.

However, for function literals, we *don't* want to apply this
rewriting to the underlying function. Because within the function
literal (when it's not itself inlined), the inlining context (if any)
will have already be available at the caller PC instead.

Unified IR was already getting this right in the case of user-written
statements within the function literal, which is what the unit test
for #46234 tested. However, it was still using inline-adjusted
positions for the function declaration and its parameters, which
occasionally end up getting used for generated code (e.g., loading
captured values from the closure record).

I've manually verified that this fixes the hang in
https://go.dev/play/p/avQ0qgRzOgt, and spot-checked the
-d=pctab=pctoinline output for kube-apiserver and kubelet and they
seem better.

However, I'm still working on a more robust test for this (hence
"Updates" not "Fixes") and internal assertions to verify that we're
emitting correct inline trees. In particular, there are still other
cases (even in the non-unified frontend) where we're producing
corrupt (but at least acyclic) inline trees.

Updates #54625.

Change-Id: Iacfd2e1eb06ae8dc299c0679f377461d3d46c15a
Reviewed-on: https://go-review.googlesource.com/c/go/+/425395
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2022-08-25 18:46:22 +00:00

22 lines
773 B
Go

// errorcheckwithauto -0 -m -d=inlfuncswithclosures=1
//go:build goexperiment.unified
// +build goexperiment.unified
// Copyright 2022 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 foo
func r(z int) int {
foo := func(x int) int { // ERROR "can inline r.func1" "func literal does not escape"
return x + z
}
bar := func(x int) int { // ERROR "func literal does not escape" "can inline r.func2"
return x + func(y int) int { // ERROR "can inline r.func2.1" "can inline r.func3"
return 2*y + x*z
}(x) // ERROR "inlining call to r.func2.1"
}
return foo(42) + bar(42) // ERROR "inlining call to r.func1" "inlining call to r.func2" "inlining call to r.func3"
}