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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 13:14:23 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 13:14:23 +0000 |
commit | 73df946d56c74384511a194dd01dbe099584fd1a (patch) | |
tree | fd0bcea490dd81327ddfbb31e215439672c9a068 /test/fixedbugs/issue21655.go | |
parent | Initial commit. (diff) | |
download | golang-1.16-upstream.tar.xz golang-1.16-upstream.zip |
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'test/fixedbugs/issue21655.go')
-rw-r--r-- | test/fixedbugs/issue21655.go | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/test/fixedbugs/issue21655.go b/test/fixedbugs/issue21655.go new file mode 100644 index 0000000..66d4e3a --- /dev/null +++ b/test/fixedbugs/issue21655.go @@ -0,0 +1,62 @@ +// compile + +// Copyright 2017 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. + +// Make sure assembly offsets don't get too large. + +// To trigger issue21655, the index offset needs to be small +// enough to fit into an int32 (to get rewritten to an ADDQconst) +// but large enough to overflow an int32 after multiplying by the stride. + +package main + +func f1(a []int64, i int64) int64 { + return a[i+1<<30] +} +func f2(a []int32, i int64) int32 { + return a[i+1<<30] +} +func f3(a []int16, i int64) int16 { + return a[i+1<<30] +} +func f4(a []int8, i int64) int8 { + return a[i+1<<31] +} +func f5(a []float64, i int64) float64 { + return a[i+1<<30] +} +func f6(a []float32, i int64) float32 { + return a[i+1<<30] +} + +// Note: Before the fix for issue 21655, f{1,2,5,6} made +// the compiler crash. f3 silently generated the wrong +// code, using an offset of -1<<31 instead of 1<<31. +// (This is due to the assembler accepting offsets +// like 0x80000000 and silently using them as +// signed 32 bit offsets.) +// f4 was ok, but testing it can't hurt. + +func f7(ss []*string, i int) string { + const offset = 3 << 29 // 3<<29 * 4 = 3<<31 = 1<<31 mod 1<<32. + if i > offset { + return *ss[i-offset] + } + return "" +} +func f8(ss []*string, i int) string { + const offset = 3<<29 + 10 + if i > offset { + return *ss[i-offset] + } + return "" +} +func f9(ss []*string, i int) string { + const offset = 3<<29 - 10 + if i > offset { + return *ss[i-offset] + } + return "" +} |