1// run
2
3//go:build !wasm
4
5// Copyright 2021 The Go Authors. All rights reserved.
6// Use of this source code is governed by a BSD-style
7// license that can be found in the LICENSE file.
8
9// wasm is excluded because the compiler chatter about register abi pragma ends up
10// on stdout, and causes the expected output to not match.
11
12package main
13
14import "fmt"
15
16type i4 struct {
17	a, b, c, d int
18}
19
20//go:noinline
21func spills(px *i4) {
22}
23
24//go:registerparams
25//go:noinline
26func F(x i4) i4 {
27	ab := x.a + x.b
28	bc := x.b + x.c
29	cd := x.c + x.d
30	ad := x.a + x.d
31	ba := x.a - x.b
32	cb := x.b - x.c
33	dc := x.c - x.d
34	da := x.a - x.d
35	i := i4{ab*bc + da, cd*ad + cb, ba*cb + ad, dc*da + bc}
36	spills(&i)
37	return i
38}
39
40func main() {
41	x := i4{1, 2, 3, 4}
42	y := x
43	z := F(x)
44	if z != (i4{12, 34, 6, 8}) {
45		fmt.Printf("y=%v, z=%v\n", y, z)
46	}
47}
48