blob: e487bb89565f3fd75af9229e1843b810b9f043d5 [file] [log] [blame]
// run
// Copyright 2009 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
// Test for correct heap-moving of escaped variables.
// It is hard to check for the allocations, but it is easy
// to check that if you call the function twice at the
// same stack level, the pointers returned should be
// different.
var bad = false
var allptr = make([]*int, 0, 100)
func noalias(p, q *int, s string) {
n := len(allptr)
*p = -(n+1)
*q = -(n+2)
allptr = allptr[0:n+2]
allptr[n] = p
allptr[n+1] = q
n += 2
for i := 0; i < n; i++ {
if allptr[i] != nil && *allptr[i] != -(i+1) {
println("aliased pointers", -(i+1), *allptr[i], "after", s)
allptr[i] = nil
bad = true
}
}
}
func val(p, q *int, v int, s string) {
if *p != v {
println("wrong value want", v, "got", *p, "after", s)
bad = true
}
if *q != v+1 {
println("wrong value want", v+1, "got", *q, "after", s)
bad = true
}
}
func chk(p, q *int, v int, s string) {
val(p, q, v, s)
noalias(p, q, s)
}
func chkalias(p, q *int, v int, s string) {
if p != q {
println("want aliased pointers but got different after", s)
}
if *q != v+1 {
println("wrong value want", v+1, "got", *q, "after", s)
}
}
func i_escapes(x int) *int {
var i int
i = x
return &i
}
func j_escapes(x int) *int {
var j int = x
j = x
return &j
}
func k_escapes(x int) *int {
k := x
return &k
}
func in_escapes(x int) *int {
return &x
}
func send(c chan int, x int) {
c <- x
}
func select_escapes(x int) *int {
c := make(chan int)
go send(c, x)
select {
case req := <-c:
return &req
}
return nil
}
func select_escapes1(x int, y int) (*int, *int) {
c := make(chan int)
var a [2]int
var p [2]*int
a[0] = x
a[1] = y
for i := 0; i < 2; i++ {
go send(c, a[i])
select {
case req := <-c:
p[i] = &req
}
}
return p[0], p[1]
}
func range_escapes(x int) *int {
var a [1]int
a[0] = x
for _, v := range a {
return &v
}
return nil
}
// *is* aliased
func range_escapes2(x, y int) (*int, *int) {
var a [2]int
var p [2]*int
a[0] = x
a[1] = y
for k, v := range a {
p[k] = &v
}
return p[0], p[1]
}
// *is* aliased
func for_escapes2(x int, y int) (*int, *int) {
var p [2]*int
n := 0
for i := x; n < 2; i = y {
p[n] = &i
n++
}
return p[0], p[1]
}
func out_escapes(i int) (x int, p *int) {
x = i
p = &x // ERROR "address of out parameter"
return
}
func out_escapes_2(i int) (x int, p *int) {
x = i
return x, &x // ERROR "address of out parameter"
}
func defer1(i int) (x int) {
c := make(chan int)
go func() { x = i; c <- 1 }()
<-c
return
}
func main() {
p, q := i_escapes(1), i_escapes(2)
chk(p, q, 1, "i_escapes")
p, q = j_escapes(3), j_escapes(4)
chk(p, q, 3, "j_escapes")
p, q = k_escapes(5), k_escapes(6)
chk(p, q, 5, "k_escapes")
p, q = in_escapes(7), in_escapes(8)
chk(p, q, 7, "in_escapes")
p, q = select_escapes(9), select_escapes(10)
chk(p, q, 9, "select_escapes")
p, q = select_escapes1(11, 12)
chk(p, q, 11, "select_escapes1")
p, q = range_escapes(13), range_escapes(14)
chk(p, q, 13, "range_escapes")
p, q = range_escapes2(101, 102)
chkalias(p, q, 101, "range_escapes2")
p, q = for_escapes2(103, 104)
chkalias(p, q, 103, "for_escapes2")
_, p = out_escapes(15)
_, q = out_escapes(16)
chk(p, q, 15, "out_escapes")
_, p = out_escapes_2(17)
_, q = out_escapes_2(18)
chk(p, q, 17, "out_escapes_2")
x := defer1(20)
if x != 20 {
println("defer failed", x)
bad = true
}
if bad {
panic("BUG: no escape")
}
}