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// run
// Copyright 2024 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.
package main
import (
"fmt"
)
type someType []uint64
func (s *someType) push(v uint64) {
*s = append(*s, v)
}
func (s *someType) problematicFn(x1Lo, x1Hi, x2Lo, x2Hi uint64) {
r1 := int32(int16(x1Lo>>0)) * int32(int16(x2Lo>>0))
g()
r3 := int32(int16(x1Lo>>32)) * int32(int16(x2Lo>>32))
r4 := int32(int16(x1Lo>>48)) * int32(int16(x2Lo>>48))
r5 := int32(int16(x1Hi>>0)) * int32(int16(x2Hi>>0))
r7 := int32(int16(x1Hi>>32)) * int32(int16(x2Hi>>32))
r8 := int32(int16(x1Hi>>48)) * int32(int16(x2Hi>>48))
s.push(uint64(uint32(r1)) | (uint64(uint32(r3+r4)) << 32))
s.push(uint64(uint32(r5)) | (uint64(uint32(r7+r8)) << 32))
}
//go:noinline
func g() {
}
func main() {
s := &someType{}
s.problematicFn(0x1000100010001, 0x1000100010001, 0xffffffffffffffff, 0xffffffffffffffff)
for i := 0; i < 2; i++ {
if got, want := (*s)[i], uint64(0xfffffffeffffffff); got != want {
fmt.Printf("s[%d]=%x, want %x\n", i, got, want)
}
}
}
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