Initial commit: Go 1.23 release state

test/escape.go

@@ -0,0 +1,226 @@
+// 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
+	var k, v int
+	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
+	i := x
+	for ; 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")
+	}
+}