// Copyright 2023 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.
//go:build go1.21
// goversion can be pinned to anything strictly before 1.22.
package main
import (
"reflect"
)
func main() {
test_init()
bound()
manyvars()
nocond()
nopost()
address_sequences()
post_escapes()
// Clones from cmd/compile/internal/loopvar/testdata .
for_complicated_esc_address()
for_esc_address()
for_esc_closure()
for_esc_method()
}
// pre-go1.22 all of i will have the same address and the value of 6.
var same = func(m, n int) []*int {
var r []*int
for i := m; i <= n; i++ {
r = append(r, &i)
}
return r
}(3, 5)
func test_init() {
if len(same) != 3 {
panic(same)
}
for i := range same {
for j := range same {
if !(same[i] == same[j]) {
panic(same)
}
}
}
for i := range same {
if *(same[i]) != 6 {
panic(same)
}
}
}
func bound() {
b := func(k int) func() int {
var f func() int
for i := 0; i < k; i++ {
f = func() int { return i } // shared address will equal k.
}
return f
}
if got := b(0); got != nil {
panic(got)
}
if got := b(5); got() != 5 {
panic(got())
}
}
func manyvars() {
// Tests declaring many variables and having one in the middle escape.
var f func() int
for i, j, k, l, m, n, o, p := 7, 6, 5, 4, 3, 2, 1, 0; p < 6; l, p = l+1, p+1 {
_, _, _, _, _, _, _, _ = i, j, k, l, m, n, o, p
f = func() int { return l } // address *after* post updates l
}
if f() != 10 { // l == p+4
panic(f())
}
}
func nocond() {
var c, b, e *int
for p := 0; ; p++ {
if p%7 == 0 {
c = &p
continue
} else if p == 20 {
b = &p
break
}
e = &p
}
if *c != 20 {
panic(c)
}
if *b != 20 {
panic(b)
}
if *e != 20 {
panic(e)
}
}
func nopost() {
var first, last *int
for p := 0; p < 20; {
if first == nil {
first = &p
}
last = &p
p++
}
if *first != 20 {
panic(first)
}
if *last != 20 {
panic(last)
}
}
func address_sequences() {
var c, b, p []*int
cond := func(x *int) bool {
c = append(c, x)
return *x < 5
}
body := func(x *int) {
b = append(b, x)
}
post := func(x *int) {
p = append(p, x)
(*x)++
}
for i := 0; cond(&i); post(&i) {
body(&i)
}
if c[0] != c[1] {
panic(c)
}
if !reflect.DeepEqual(c[:5], b) {
panic(c)
}
if !reflect.DeepEqual(c[1:], p) {
panic(c)
}
if !reflect.DeepEqual(b[1:], p[:4]) {
panic(b)
}
}
func post_escapes() {
var p []*int
post := func(x *int) {
p = append(p, x)
(*x)++
}
for i := 0; i < 5; post(&i) {
}
var got []int
for _, x := range p {
got = append(got, *x)
}
if want := []int{5, 5, 5, 5, 5}; !reflect.DeepEqual(got, want) {
panic(got)
}
}
func for_complicated_esc_address() {
// Clone of for_complicated_esc_adress.go
ss, sa := shared(23)
ps, pa := private(23)
es, ea := experiment(23)
if ss != ps || ss != es || sa != ea || pa != 188 {
println("shared s, a", ss, sa, "; private, s, a", ps, pa, "; experiment s, a", es, ea)
panic("for_complicated_esc_address")
}
}
func experiment(x int) (int, int) {
sum := 0
var is []*int
for i := x; i != 1; i = i / 2 {
for j := 0; j < 10; j++ {
if i == j { // 10 skips
continue
}
sum++
}
i = i*3 + 1
if i&1 == 0 {
is = append(is, &i)
for i&2 == 0 {
i = i >> 1
}
} else {
i = i + i
}
}
asum := 0
for _, pi := range is {
asum += *pi
}
return sum, asum
}
func private(x int) (int, int) {
sum := 0
var is []*int
I := x
for ; I != 1; I = I / 2 {
i := I
for j := 0; j < 10; j++ {
if i == j { // 10 skips
I = i
continue
}
sum++
}
i = i*3 + 1
if i&1 == 0 {
is = append(is, &i)
for i&2 == 0 {
i = i >> 1
}
} else {
i = i + i
}
I = i
}
asum := 0
for _, pi := range is {
asum += *pi
}
return sum, asum
}
func shared(x int) (int, int) {
sum := 0
var is []*int
i := x
for ; i != 1; i = i / 2 {
for j := 0; j < 10; j++ {
if i == j { // 10 skips
continue
}
sum++
}
i = i*3 + 1
if i&1 == 0 {
is = append(is, &i)
for i&2 == 0 {
i = i >> 1
}
} else {
i = i + i
}
}
asum := 0
for _, pi := range is {
asum += *pi
}
return sum, asum
}
func for_esc_address() {
// Clone of for_esc_address.go
sum := 0
var is []*int
for i := 0; i < 10; i++ {
for j := 0; j < 10; j++ {
if i == j { // 10 skips
continue
}
sum++
}
if i&1 == 0 {
is = append(is, &i)
}
}
bug := false
if sum != 100-10 {
println("wrong sum, expected", 90, ", saw", sum)
bug = true
}
if len(is) != 5 {
println("wrong iterations, expected ", 5, ", saw", len(is))
bug = true
}
sum = 0
for _, pi := range is {
sum += *pi
}
if sum != 10+10+10+10+10 {
println("wrong sum, expected ", 50, ", saw ", sum)
bug = true
}
if bug {
panic("for_esc_address")
}
}
func for_esc_closure() {
// Clone of for_esc_closure.go
var is []func() int
sum := 0
for i := 0; i < 10; i++ {
for j := 0; j < 10; j++ {
if i == j { // 10 skips
continue
}
sum++
}
if i&1 == 0 {
is = append(is, func() int {
if i%17 == 15 {
i++
}
return i
})
}
}
bug := false
if sum != 100-10 {
println("wrong sum, expected ", 90, ", saw", sum)
bug = true
}
if len(is) != 5 {
println("wrong iterations, expected ", 5, ", saw", len(is))
bug = true
}
sum = 0
for _, f := range is {
sum += f()
}
if sum != 10+10+10+10+10 {
println("wrong sum, expected ", 50, ", saw ", sum)
bug = true
}
if bug {
panic("for_esc_closure")
}
}
type I int
func (x *I) method() int {
return int(*x)
}
func for_esc_method() {
// Clone of for_esc_method.go
sum := 0
var is []func() int
for i := I(0); int(i) < 10; i++ {
for j := 0; j < 10; j++ {
if int(i) == j { // 10 skips
continue
}
sum++
}
if i&1 == 0 {
is = append(is, i.method)
}
}
bug := false
if sum != 100-10 {
println("wrong sum, expected ", 90, ", saw ", sum)
bug = true
}
if len(is) != 5 {
println("wrong iterations, expected ", 5, ", saw", len(is))
bug = true
}
sum = 0
for _, m := range is {
sum += m()
}
if sum != 10+10+10+10+10 {
println("wrong sum, expected ", 50, ", saw ", sum)
bug = true
}
if bug {
panic("for_esc_method")
}
}
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