mirror of
https://github.com/golang/go
synced 2024-11-25 14:37:56 -07:00
a19cf510af
Currently, "x &^ y" gets rewriten into "x & ^y" during walk. It adds unnecessary complexity to other parts, which must aware about this. Instead, we can just implement "&^" in the conversion to SSA, so "&^" can be handled like other binary operators. However, this CL does not pass toolstash-check. It seems that implements "&^" in the conversion to SSA causes registers allocation change. With the parent: obj: 00212 (.../src/runtime/complex.go:47) MOVQ X0, AX obj: 00213 (.../src/runtime/complex.go:47) BTRQ $63, AX obj: 00214 (.../src/runtime/complex.go:47) MOVQ "".n(SP), CX obj: 00215 (.../src/runtime/complex.go:47) MOVQ $-9223372036854775808, DX obj: 00216 (.../src/runtime/complex.go:47) ANDQ DX, CX obj: 00217 (.../src/runtime/complex.go:47) ORQ AX, CX With this CL: obj: 00212 (.../src/runtime/complex.go:47) MOVQ X0, AX obj: 00213 (.../src/runtime/complex.go:47) BTRQ $63, AX obj: 00214 (.../src/runtime/complex.go:47) MOVQ $-9223372036854775808, CX obj: 00215 (.../src/runtime/complex.go:47) MOVQ "".n(SP), DX obj: 00216 (.../src/runtime/complex.go:47) ANDQ CX, DX obj: 00217 (.../src/runtime/complex.go:47) ORQ AX, DX Change-Id: I80acf8496a91be4804fb7ef3df04c19baae2754c Reviewed-on: https://go-review.googlesource.com/c/go/+/264660 Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com> Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Matthew Dempsky <mdempsky@google.com>
285 lines
6.1 KiB
Go
285 lines
6.1 KiB
Go
// errorcheck -0 -m -l
|
|
|
|
// Copyright 2012 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.
|
|
|
|
// Test, using compiler diagnostic flags, that bounds check elimination
|
|
// is eliminating the correct checks.
|
|
|
|
package foo
|
|
|
|
var (
|
|
s []int
|
|
|
|
a1 [1]int
|
|
a1k [1000]int
|
|
a100k [100000]int
|
|
|
|
p1 *[1]int
|
|
p1k *[1000]int
|
|
p100k *[100000]int
|
|
|
|
i int
|
|
ui uint
|
|
i8 int8
|
|
ui8 uint8
|
|
i16 int16
|
|
ui16 uint16
|
|
i32 int32
|
|
ui32 uint32
|
|
i64 int64
|
|
ui64 uint64
|
|
)
|
|
|
|
func main() {
|
|
// Most things need checks.
|
|
use(s[i])
|
|
use(a1[i])
|
|
use(a1k[i])
|
|
use(a100k[i])
|
|
use(p1[i])
|
|
use(p1k[i])
|
|
use(p100k[i])
|
|
|
|
use(s[ui])
|
|
use(a1[ui])
|
|
use(a1k[ui])
|
|
use(a100k[ui])
|
|
use(p1[ui])
|
|
use(p1k[ui])
|
|
use(p100k[ui])
|
|
|
|
use(s[i8])
|
|
use(a1[i8])
|
|
use(a1k[i8])
|
|
use(a100k[i8])
|
|
use(p1[i8])
|
|
use(p1k[i8])
|
|
use(p100k[i8])
|
|
|
|
// Unsigned 8-bit numbers don't need checks for len >= 2⁸.
|
|
use(s[ui8])
|
|
use(a1[ui8])
|
|
use(a1k[ui8]) // ERROR "index bounds check elided"
|
|
use(a100k[ui8]) // ERROR "index bounds check elided"
|
|
use(p1[ui8])
|
|
use(p1k[ui8]) // ERROR "index bounds check elided"
|
|
use(p100k[ui8]) // ERROR "index bounds check elided"
|
|
|
|
use(s[i16])
|
|
use(a1[i16])
|
|
use(a1k[i16])
|
|
use(a100k[i16])
|
|
use(p1[i16])
|
|
use(p1k[i16])
|
|
use(p100k[i16])
|
|
|
|
// Unsigned 16-bit numbers don't need checks for len >= 2¹⁶.
|
|
use(s[ui16])
|
|
use(a1[ui16])
|
|
use(a1k[ui16])
|
|
use(a100k[ui16]) // ERROR "index bounds check elided"
|
|
use(p1[ui16])
|
|
use(p1k[ui16])
|
|
use(p100k[ui16]) // ERROR "index bounds check elided"
|
|
|
|
use(s[i32])
|
|
use(a1[i32])
|
|
use(a1k[i32])
|
|
use(a100k[i32])
|
|
use(p1[i32])
|
|
use(p1k[i32])
|
|
use(p100k[i32])
|
|
|
|
use(s[ui32])
|
|
use(a1[ui32])
|
|
use(a1k[ui32])
|
|
use(a100k[ui32])
|
|
use(p1[ui32])
|
|
use(p1k[ui32])
|
|
use(p100k[ui32])
|
|
|
|
use(s[i64])
|
|
use(a1[i64])
|
|
use(a1k[i64])
|
|
use(a100k[i64])
|
|
use(p1[i64])
|
|
use(p1k[i64])
|
|
use(p100k[i64])
|
|
|
|
use(s[ui64])
|
|
use(a1[ui64])
|
|
use(a1k[ui64])
|
|
use(a100k[ui64])
|
|
use(p1[ui64])
|
|
use(p1k[ui64])
|
|
use(p100k[ui64])
|
|
|
|
// Mod truncates the maximum value to one less than the argument,
|
|
// but signed mod can be negative, so only unsigned mod counts.
|
|
use(s[i%999])
|
|
use(a1[i%999])
|
|
use(a1k[i%999])
|
|
use(a100k[i%999])
|
|
use(p1[i%999])
|
|
use(p1k[i%999])
|
|
use(p100k[i%999])
|
|
|
|
use(s[ui%999])
|
|
use(a1[ui%999])
|
|
use(a1k[ui%999]) // ERROR "index bounds check elided"
|
|
use(a100k[ui%999]) // ERROR "index bounds check elided"
|
|
use(p1[ui%999])
|
|
use(p1k[ui%999]) // ERROR "index bounds check elided"
|
|
use(p100k[ui%999]) // ERROR "index bounds check elided"
|
|
|
|
use(s[i%1000])
|
|
use(a1[i%1000])
|
|
use(a1k[i%1000])
|
|
use(a100k[i%1000])
|
|
use(p1[i%1000])
|
|
use(p1k[i%1000])
|
|
use(p100k[i%1000])
|
|
|
|
use(s[ui%1000])
|
|
use(a1[ui%1000])
|
|
use(a1k[ui%1000]) // ERROR "index bounds check elided"
|
|
use(a100k[ui%1000]) // ERROR "index bounds check elided"
|
|
use(p1[ui%1000])
|
|
use(p1k[ui%1000]) // ERROR "index bounds check elided"
|
|
use(p100k[ui%1000]) // ERROR "index bounds check elided"
|
|
|
|
use(s[i%1001])
|
|
use(a1[i%1001])
|
|
use(a1k[i%1001])
|
|
use(a100k[i%1001])
|
|
use(p1[i%1001])
|
|
use(p1k[i%1001])
|
|
use(p100k[i%1001])
|
|
|
|
use(s[ui%1001])
|
|
use(a1[ui%1001])
|
|
use(a1k[ui%1001])
|
|
use(a100k[ui%1001]) // ERROR "index bounds check elided"
|
|
use(p1[ui%1001])
|
|
use(p1k[ui%1001])
|
|
use(p100k[ui%1001]) // ERROR "index bounds check elided"
|
|
|
|
// Bitwise and truncates the maximum value to the mask value.
|
|
// The result (for a positive mask) cannot be negative, so elision
|
|
// applies to both signed and unsigned indexes.
|
|
use(s[i&999])
|
|
use(a1[i&999])
|
|
use(a1k[i&999]) // ERROR "index bounds check elided"
|
|
use(a100k[i&999]) // ERROR "index bounds check elided"
|
|
use(p1[i&999])
|
|
use(p1k[i&999]) // ERROR "index bounds check elided"
|
|
use(p100k[i&999]) // ERROR "index bounds check elided"
|
|
|
|
use(s[ui&999])
|
|
use(a1[ui&999])
|
|
use(a1k[ui&999]) // ERROR "index bounds check elided"
|
|
use(a100k[ui&999]) // ERROR "index bounds check elided"
|
|
use(p1[ui&999])
|
|
use(p1k[ui&999]) // ERROR "index bounds check elided"
|
|
use(p100k[ui&999]) // ERROR "index bounds check elided"
|
|
|
|
use(s[i&1000])
|
|
use(a1[i&1000])
|
|
use(a1k[i&1000])
|
|
use(a100k[i&1000]) // ERROR "index bounds check elided"
|
|
use(p1[i&1000])
|
|
use(p1k[i&1000])
|
|
use(p100k[i&1000]) // ERROR "index bounds check elided"
|
|
|
|
use(s[ui&1000])
|
|
use(a1[ui&1000])
|
|
use(a1k[ui&1000])
|
|
use(a100k[ui&1000]) // ERROR "index bounds check elided"
|
|
use(p1[ui&1000])
|
|
use(p1k[ui&1000])
|
|
use(p100k[ui&1000]) // ERROR "index bounds check elided"
|
|
|
|
use(a1[i&^-1]) // ERROR "index bounds check elided"
|
|
use(a1[i&^0])
|
|
use(a1[i&^-2])
|
|
use(a1[i&^1])
|
|
use(a1k[i&^-1]) // ERROR "index bounds check elided"
|
|
use(a1k[i&^0])
|
|
use(a1k[i&^-2]) // ERROR "index bounds check elided"
|
|
use(a1k[i&^1])
|
|
use(a1k[i8&^0])
|
|
use(a1k[i8&^-128]) // ERROR "index bounds check elided"
|
|
use(a1k[ui8&^1]) // ERROR "index bounds check elided"
|
|
use(a1k[ui16&^0xf000])
|
|
use(a1k[ui16&^0xff00]) // ERROR "index bounds check elided"
|
|
|
|
// Right shift cuts the effective number of bits in the index,
|
|
// but only for unsigned (signed stays negative).
|
|
use(s[i32>>22])
|
|
use(a1[i32>>22])
|
|
use(a1k[i32>>22])
|
|
use(a100k[i32>>22])
|
|
use(p1[i32>>22])
|
|
use(p1k[i32>>22])
|
|
use(p100k[i32>>22])
|
|
|
|
use(s[ui32>>22])
|
|
use(a1[ui32>>22])
|
|
use(a1k[ui32>>22])
|
|
use(a100k[ui32>>22]) // ERROR "index bounds check elided"
|
|
use(p1[ui32>>22])
|
|
use(p1k[ui32>>22])
|
|
use(p100k[ui32>>22]) // ERROR "index bounds check elided"
|
|
|
|
use(s[i32>>23])
|
|
use(a1[i32>>23])
|
|
use(a1k[i32>>23])
|
|
use(a100k[i32>>23])
|
|
use(p1[i32>>23])
|
|
use(p1k[i32>>23])
|
|
use(p100k[i32>>23])
|
|
|
|
use(s[ui32>>23])
|
|
use(a1[ui32>>23])
|
|
use(a1k[ui32>>23]) // ERROR "index bounds check elided"
|
|
use(a100k[ui32>>23]) // ERROR "index bounds check elided"
|
|
use(p1[ui32>>23])
|
|
use(p1k[ui32>>23]) // ERROR "index bounds check elided"
|
|
use(p100k[ui32>>23]) // ERROR "index bounds check elided"
|
|
|
|
// Division cuts the range like right shift does.
|
|
use(s[i/1e6])
|
|
use(a1[i/1e6])
|
|
use(a1k[i/1e6])
|
|
use(a100k[i/1e6])
|
|
use(p1[i/1e6])
|
|
use(p1k[i/1e6])
|
|
use(p100k[i/1e6])
|
|
|
|
use(s[ui/1e6])
|
|
use(a1[ui/1e6])
|
|
use(a1k[ui/1e6])
|
|
use(p1[ui/1e6])
|
|
use(p1k[ui/1e6])
|
|
|
|
use(s[i/1e7])
|
|
use(a1[i/1e7])
|
|
use(a1k[i/1e7])
|
|
use(a100k[i/1e7])
|
|
use(p1[i/1e7])
|
|
use(p1k[i/1e7])
|
|
use(p100k[i/1e7])
|
|
|
|
use(s[ui/1e7])
|
|
use(a1[ui/1e7])
|
|
use(p1[ui/1e7])
|
|
}
|
|
|
|
var sum int
|
|
|
|
func use(x int) {
|
|
sum += x
|
|
}
|