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7e9d55eeeb
For non-unit increment, loopbce checks to see if the increment evenly divides the difference between (constant) loop start and end. This test panics when the increment is zero. Fix: check for zero, if found, don't optimize the loop. Also added missing copyright notice to loopbce.go. Fixes #26043. Change-Id: I5f460104879cacc94481949234c9ce8c519d6380 Reviewed-on: https://go-review.googlesource.com/120759 Run-TryBot: David Chase <drchase@google.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
33 lines
543 B
Go
33 lines
543 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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// This program results in a loop inferred to increment
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// j by 0, causing bounds check elimination to attempt
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// something%0, which panics (in the bug).
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package q
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func f() {
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var s1 string
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var b bool
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if b {
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b = !b
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s1 += "a"
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}
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var s2 string
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var i, j int
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if (s1 <= "") || (s2 >= "") {
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j = len(s1[:6])
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} else {
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i = len("b")
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}
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for j < 0 {
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j += i
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}
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}
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