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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 *string
var y int
//go:registerparams
//go:noinline
func F(a, b, c *int) (x int) {
x = *a
G(&x)
x += *b
G(&x)
x += *c
G(&x)
return
}
//go:registerparams
//go:noinline
func G(x *int) {
y += *x
fmt.Println("y = ", y)
}
//go:registerparams
//go:noinline
func X() {
*sink += " !!!!!!!!!!!!!!!"
}
//go:registerparams
//go:noinline
func H(s, t string) (result string) { // result leaks to heap
result = "Aloha! " + s + " " + t
sink = &result
r := ""
if len(s) <= len(t) {
r = "OKAY! "
X()
}
return r + result
}
//go:registerparams
//go:noinline
func K(s, t string) (result string) { // result spills
result = "Aloha! " + s + " " + t
r := ""
if len(s) <= len(t) {
r = "OKAY! "
X()
}
return r + result
}
func main() {
a, b, c := 1, 4, 16
x := F(&a, &b, &c)
fmt.Printf("x = %d\n", x)
y := H("Hello", "World!")
fmt.Println("len(y) =", len(y))
fmt.Println("y =", y)
z := H("Hello", "Pal!")
fmt.Println("len(z) =", len(z))
fmt.Println("z =", z)
fmt.Println()
y = K("Hello", "World!")
fmt.Println("len(y) =", len(y))
fmt.Println("y =", y)
z = K("Hello", "Pal!")
fmt.Println("len(z) =", len(z))
fmt.Println("z =", z)
}
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