1// run
2
3// Copyright 2015 The Go Authors. All rights reserved.
4// Use of this source code is governed by a BSD-style
5// license that can be found in the LICENSE file.
6
7package main
8
9// Make sure the compiler knows that DUFFCOPY clobbers X0
10
11import "fmt"
12
13//go:noinline
14func f(x float64) float64 {
15	// y is allocated to X0
16	y := x + 5
17	// marshals z before y.  Marshaling z
18	// calls DUFFCOPY.
19	return g(z, y)
20}
21
22//go:noinline
23func g(b [64]byte, y float64) float64 {
24	return y
25}
26
27var z [64]byte
28
29func main() {
30	got := f(5)
31	if got != 10 {
32		panic(fmt.Sprintf("want 10, got %f", got))
33	}
34}
35