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85cfa4d55e
If both branches of a write barrier test go to the same block, then there's no unsafe points. This can only happen if the resulting memory state is somehow dead, which can only occur in degenerate cases, like infinite loops. No point in cleaning up the useless branch in these situations. Fixes #26024. Change-Id: I93a7df9fdf2fc94c6c4b1fe61180dc4fd4a0871f Reviewed-on: https://go-review.googlesource.com/123655 Reviewed-by: David Chase <drchase@google.com> Run-TryBot: Keith Randall <khr@golang.org> TryBot-Result: Gobot Gobot <gobot@golang.org>
29 lines
614 B
Go
29 lines
614 B
Go
// compile
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// Copyright 2018 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package r
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// f compiles into code where no stores remain in the two successors
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// of a write barrier block; i.e., they are empty. Pre-fix, this
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// results in an unexpected input to markUnsafePoints, that expects to
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// see a pair of non-empty plain blocks.
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func f() {
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var i int
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var s string
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for len(s) < len(s) {
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i++
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s = "a"
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}
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var b bool
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var sa []string
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for true {
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sa = []string{""}
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for b || i == 0 {
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}
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b = !b
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_ = sa
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}
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}
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