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// run
//go:build !wasm
// +build !wasm
// Copyright 2021 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.
// wasm is excluded because the compiler chatter about register abi pragma ends up
// on stdout, and causes the expected output to not match.
package main
import (
"fmt"
)
var sink int = 3
//go:registerparams
//go:noinline
func F(a, b, c, d, e, f *int) {
G(f, e, d, c, b, a)
sink += *a // *a == 6 after swapping in G
}
//go:registerparams
//go:noinline
func G(a, b, c, d, e, f *int) {
var scratch [1000 * 100]int
scratch[*a] = *f // scratch[6] = 1
fmt.Println(*a, *b, *c, *d, *e, *f) // Forces it to spill b
sink = scratch[*b+1] // scratch[5+1] == 1
*f, *a = *a, *f
*e, *b = *b, *e
*d, *c = *c, *d
}
func main() {
a, b, c, d, e, f := 1, 2, 3, 4, 5, 6
F(&a, &b, &c, &d, &e, &f)
fmt.Println(a, b, c, d, e, f)
fmt.Println(sink)
}
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