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-rw-r--r--test/escape.go224
1 files changed, 224 insertions, 0 deletions
diff --git a/test/escape.go b/test/escape.go
new file mode 100644
index 0000000..252a1e5
--- /dev/null
+++ b/test/escape.go
@@ -0,0 +1,224 @@
+// 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)
+ bad = true
+ }
+ if *q != v+1 {
+ println("wrong value want", v+1, "got", *q, "after", s)
+ bad = true
+ }
+}
+
+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 for_escapes3(x int, y int) (*int, *int) {
+ var f [2]func() *int
+ n := 0
+ for i := x; n < 2; i = y {
+ p := new(int)
+ *p = i
+ f[n] = func() *int { return p }
+ n++
+ }
+ return f[0](), f[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, q = for_escapes3(105, 106)
+ chk(p, q, 105, "for_escapes3")
+
+ _, 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")
+ }
+}