mirror of
https://github.com/golang/go
synced 2024-11-18 12:24:48 -07:00
4fc45ae879
Match more patterns generated by the compiler where the index for a bound check is bounded through a AND operation, with different register sizes. These rules trigger a dozen of times in a bootstrap. Change-Id: Ic9fff16f21d08580f19a366c3ee1a372e58357d1 Reviewed-on: https://go-review.googlesource.com/37442 TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Keith Randall <khr@golang.org>
148 lines
2.7 KiB
Go
148 lines
2.7 KiB
Go
// +build amd64
|
|
// errorcheck -0 -d=ssa/check_bce/debug=3
|
|
|
|
package main
|
|
|
|
func f0(a []int) {
|
|
a[0] = 1 // ERROR "Found IsInBounds$"
|
|
a[0] = 1
|
|
a[6] = 1 // ERROR "Found IsInBounds$"
|
|
a[6] = 1
|
|
a[5] = 1
|
|
a[5] = 1
|
|
}
|
|
|
|
func f1(a [256]int, i int) {
|
|
var j int
|
|
useInt(a[i]) // ERROR "Found IsInBounds$"
|
|
j = i % 256
|
|
useInt(a[j]) // ERROR "Found IsInBounds$"
|
|
j = i & 255
|
|
useInt(a[j])
|
|
j = i & 17
|
|
useInt(a[j])
|
|
|
|
if 4 <= i && i < len(a) {
|
|
useInt(a[i])
|
|
useInt(a[i-1]) // ERROR "Found IsInBounds$"
|
|
// TODO: 'if 4 <= i && i < len(a)' gets rewritten to 'if uint(i - 4) < 256 - 4',
|
|
// which the bounds checker cannot yet use to infer that the next line doesn't need a bounds check.
|
|
useInt(a[i-4])
|
|
}
|
|
}
|
|
|
|
func f2(a [256]int, i uint) {
|
|
useInt(a[i]) // ERROR "Found IsInBounds$"
|
|
j := i % 256
|
|
useInt(a[j])
|
|
j = i & 255
|
|
useInt(a[j])
|
|
j = i & 17
|
|
useInt(a[j])
|
|
}
|
|
|
|
func f2a(a [35]int, i uint8) {
|
|
useInt(a[i]) // ERROR "Found IsInBounds$"
|
|
j := i & 34
|
|
useInt(a[j])
|
|
j = i & 17
|
|
useInt(a[j])
|
|
}
|
|
|
|
func f2b(a [35]int, i uint16) {
|
|
useInt(a[i]) // ERROR "Found IsInBounds$"
|
|
j := i & 34
|
|
useInt(a[j])
|
|
j = i & 17
|
|
useInt(a[j])
|
|
}
|
|
|
|
func f2c(a [35]int, i uint32) {
|
|
useInt(a[i]) // ERROR "Found IsInBounds$"
|
|
j := i & 34
|
|
useInt(a[j])
|
|
j = i & 17
|
|
useInt(a[j])
|
|
}
|
|
|
|
func f3(a [256]int, i uint8) {
|
|
useInt(a[i])
|
|
useInt(a[i+10])
|
|
useInt(a[i+14])
|
|
}
|
|
|
|
func f4(a [27]int, i uint8) {
|
|
useInt(a[i%15])
|
|
useInt(a[i%19])
|
|
useInt(a[i%27])
|
|
}
|
|
|
|
func f5(a []int) {
|
|
if len(a) > 5 {
|
|
useInt(a[5])
|
|
useSlice(a[6:])
|
|
useSlice(a[:6])
|
|
}
|
|
}
|
|
|
|
func f6(a [32]int, b [64]int, i int) {
|
|
useInt(a[uint32(i*0x07C4ACDD)>>27])
|
|
useInt(b[uint64(i*0x07C4ACDD)>>58])
|
|
useInt(a[uint(i*0x07C4ACDD)>>59])
|
|
|
|
// The following bounds should not be removed because they can overflow.
|
|
useInt(a[uint32(i*0x106297f105d0cc86)>>26]) // ERROR "Found IsInBounds$"
|
|
useInt(b[uint64(i*0x106297f105d0cc86)>>57]) // ERROR "Found IsInBounds$"
|
|
useInt(a[int32(i*0x106297f105d0cc86)>>26]) // ERROR "Found IsInBounds$"
|
|
useInt(b[int64(i*0x106297f105d0cc86)>>57]) // ERROR "Found IsInBounds$"
|
|
}
|
|
|
|
func g1(a []int) {
|
|
for i := range a {
|
|
a[i] = i
|
|
useSlice(a[:i+1])
|
|
useSlice(a[:i])
|
|
}
|
|
}
|
|
|
|
func g2(a []int) {
|
|
useInt(a[3]) // ERROR "Found IsInBounds$"
|
|
useInt(a[2])
|
|
useInt(a[1])
|
|
useInt(a[0])
|
|
}
|
|
|
|
func g3(a []int) {
|
|
for i := range a[:256] { // ERROR "Found IsSliceInBounds$"
|
|
useInt(a[i]) // ERROR "Found IsInBounds$"
|
|
}
|
|
b := a[:256]
|
|
for i := range b {
|
|
useInt(b[i])
|
|
}
|
|
}
|
|
|
|
func g4(a [100]int) {
|
|
for i := 10; i < 50; i++ {
|
|
useInt(a[i-10])
|
|
useInt(a[i])
|
|
useInt(a[i+25])
|
|
useInt(a[i+50])
|
|
|
|
// The following are out of bounds.
|
|
useInt(a[i-11]) // ERROR "Found IsInBounds$"
|
|
useInt(a[i+51]) // ERROR "Found IsInBounds$"
|
|
}
|
|
}
|
|
|
|
//go:noinline
|
|
func useInt(a int) {
|
|
}
|
|
|
|
//go:noinline
|
|
func useSlice(a []int) {
|
|
}
|
|
|
|
func main() {
|
|
}
|