1// run 2 3// Copyright 2009 The Go Authors. All rights reserved. 4// Use of this source code is governed by a BSD-style 5// license that can be found in the LICENSE file. 6 7package main 8 9// Test for correct heap-moving of escaped variables. 10// It is hard to check for the allocations, but it is easy 11// to check that if you call the function twice at the 12// same stack level, the pointers returned should be 13// different. 14 15var bad = false 16 17var allptr = make([]*int, 0, 100) 18 19func noalias(p, q *int, s string) { 20 n := len(allptr) 21 *p = -(n + 1) 22 *q = -(n + 2) 23 allptr = allptr[0 : n+2] 24 allptr[n] = p 25 allptr[n+1] = q 26 n += 2 27 for i := 0; i < n; i++ { 28 if allptr[i] != nil && *allptr[i] != -(i+1) { 29 println("aliased pointers", -(i + 1), *allptr[i], "after", s) 30 allptr[i] = nil 31 bad = true 32 } 33 } 34} 35 36func val(p, q *int, v int, s string) { 37 if *p != v { 38 println("wrong value want", v, "got", *p, "after", s) 39 bad = true 40 } 41 if *q != v+1 { 42 println("wrong value want", v+1, "got", *q, "after", s) 43 bad = true 44 } 45} 46 47func chk(p, q *int, v int, s string) { 48 val(p, q, v, s) 49 noalias(p, q, s) 50} 51 52func chkalias(p, q *int, v int, s string) { 53 if p != q { 54 println("want aliased pointers but got different after", s) 55 } 56 if *q != v+1 { 57 println("wrong value want", v+1, "got", *q, "after", s) 58 } 59} 60 61func i_escapes(x int) *int { 62 var i int 63 i = x 64 return &i 65} 66 67func j_escapes(x int) *int { 68 var j int = x 69 j = x 70 return &j 71} 72 73func k_escapes(x int) *int { 74 k := x 75 return &k 76} 77 78func in_escapes(x int) *int { 79 return &x 80} 81 82func send(c chan int, x int) { 83 c <- x 84} 85 86func select_escapes(x int) *int { 87 c := make(chan int) 88 go send(c, x) 89 select { 90 case req := <-c: 91 return &req 92 } 93 return nil 94} 95 96func select_escapes1(x int, y int) (*int, *int) { 97 c := make(chan int) 98 var a [2]int 99 var p [2]*int 100 a[0] = x 101 a[1] = y 102 for i := 0; i < 2; i++ { 103 go send(c, a[i]) 104 select { 105 case req := <-c: 106 p[i] = &req 107 } 108 } 109 return p[0], p[1] 110} 111 112func range_escapes(x int) *int { 113 var a [1]int 114 a[0] = x 115 for _, v := range a { 116 return &v 117 } 118 return nil 119} 120 121// *is* aliased 122func range_escapes2(x, y int) (*int, *int) { 123 var a [2]int 124 var p [2]*int 125 a[0] = x 126 a[1] = y 127 for k, v := range a { 128 p[k] = &v 129 } 130 return p[0], p[1] 131} 132 133// *is* aliased 134func for_escapes2(x int, y int) (*int, *int) { 135 var p [2]*int 136 n := 0 137 for i := x; n < 2; i = y { 138 p[n] = &i 139 n++ 140 } 141 return p[0], p[1] 142} 143 144func for_escapes3(x int, y int) (*int, *int) { 145 var f [2]func() *int 146 n := 0 147 for i := x; n < 2; i = y { 148 p := new(int) 149 *p = i 150 f[n] = func() *int { return p } 151 n++ 152 } 153 return f[0](), f[1]() 154} 155 156func out_escapes(i int) (x int, p *int) { 157 x = i 158 p = &x // ERROR "address of out parameter" 159 return 160} 161 162func out_escapes_2(i int) (x int, p *int) { 163 x = i 164 return x, &x // ERROR "address of out parameter" 165} 166 167func defer1(i int) (x int) { 168 c := make(chan int) 169 go func() { x = i; c <- 1 }() 170 <-c 171 return 172} 173 174func main() { 175 p, q := i_escapes(1), i_escapes(2) 176 chk(p, q, 1, "i_escapes") 177 178 p, q = j_escapes(3), j_escapes(4) 179 chk(p, q, 3, "j_escapes") 180 181 p, q = k_escapes(5), k_escapes(6) 182 chk(p, q, 5, "k_escapes") 183 184 p, q = in_escapes(7), in_escapes(8) 185 chk(p, q, 7, "in_escapes") 186 187 p, q = select_escapes(9), select_escapes(10) 188 chk(p, q, 9, "select_escapes") 189 190 p, q = select_escapes1(11, 12) 191 chk(p, q, 11, "select_escapes1") 192 193 p, q = range_escapes(13), range_escapes(14) 194 chk(p, q, 13, "range_escapes") 195 196 p, q = range_escapes2(101, 102) 197 chkalias(p, q, 101, "range_escapes2") 198 199 p, q = for_escapes2(103, 104) 200 chkalias(p, q, 103, "for_escapes2") 201 202 p, q = for_escapes3(105, 106) 203 chk(p, q, 105, "for_escapes3") 204 205 _, p = out_escapes(15) 206 _, q = out_escapes(16) 207 chk(p, q, 15, "out_escapes") 208 209 _, p = out_escapes_2(17) 210 _, q = out_escapes_2(18) 211 chk(p, q, 17, "out_escapes_2") 212 213 x := defer1(20) 214 if x != 20 { 215 println("defer failed", x) 216 bad = true 217 } 218 219 if bad { 220 panic("BUG: no escape") 221 } 222} 223