You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
63 lines
1.5 KiB
63 lines
1.5 KiB
// 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 ""
|
|
}
|