From ccd992355df7192993c666236047820244914598 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Tue, 16 Apr 2024 21:19:13 +0200 Subject: Adding upstream version 1.21.8. Signed-off-by: Daniel Baumann --- test/fixedbugs/issue41780.go | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 test/fixedbugs/issue41780.go (limited to 'test/fixedbugs/issue41780.go') diff --git a/test/fixedbugs/issue41780.go b/test/fixedbugs/issue41780.go new file mode 100644 index 0000000..632c144 --- /dev/null +++ b/test/fixedbugs/issue41780.go @@ -0,0 +1,39 @@ +// run + +// Copyright 2020 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. + +// Checks that conversion of CMP(x,-y) -> CMN(x,y) is only applied in correct context. + +package main + +type decimal struct { + d [8]byte // digits, big-endian representation + dp int // decimal point +} + +var powtab = []int{1, 3, 6, 9, 13, 16, 19, 23, 26} + +//go:noinline +func foo(d *decimal) int { + exp := int(d.d[1]) + if d.dp < 0 || d.dp == 0 && d.d[0] < '5' { + var n int + if -d.dp >= len(powtab) { + n = 27 + } else { + n = powtab[-d.dp] // incorrect CMP -> CMN substitution causes indexing panic. + } + exp += n + } + return exp +} + +func main() { + var d decimal + d.d[0] = '1' + if foo(&d) != 1 { + println("FAILURE (though not the one this test was written to catch)") + } +} -- cgit v1.2.3