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// 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
}
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