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go/test/reorder.go
Dhananjay Nakrani 1cde87b312 cmd/compile: Ensure left-to-right assignment
Add temporaries to reorder the assignment for OAS2XXX nodes.
This makes orderstmt(), rewrite
  a, b, c = ...
as
  tmp1, tmp2, tmp3 = ...
  a, b, c = tmp1, tmp2, tmp3
and
  a, ok = ...
as
  t1, t2 = ...
  a  = t1
  ok = t2

Fixes #13433.

Change-Id: Id0f5956e3a254d0a6f4b89b5f7b0e055b1f0e21f
Reviewed-on: https://go-review.googlesource.com/34713
Run-TryBot: Dhananjay Nakrani <dhananjayn@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-11 21:46:21 +00:00

152 lines
2.1 KiB
Go

// run
// Copyright 2011 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.
// Test reordering of assignments.
package main
import "fmt"
func main() {
p1()
p2()
p3()
p4()
p5()
p6()
p7()
p8()
p9()
}
var gx []int
func f(i int) int {
return gx[i]
}
func check(x []int, x0, x1, x2 int) {
if x[0] != x0 || x[1] != x1 || x[2] != x2 {
fmt.Printf("%v, want %d,%d,%d\n", x, x0, x1, x2)
panic("failed")
}
}
func check3(x, y, z, xx, yy, zz int) {
if x != xx || y != yy || z != zz {
fmt.Printf("%d,%d,%d, want %d,%d,%d\n", x, y, z, xx, yy, zz)
panic("failed")
}
}
func p1() {
x := []int{1, 2, 3}
i := 0
i, x[i] = 1, 100
_ = i
check(x, 100, 2, 3)
}
func p2() {
x := []int{1, 2, 3}
i := 0
x[i], i = 100, 1
_ = i
check(x, 100, 2, 3)
}
func p3() {
x := []int{1, 2, 3}
y := x
gx = x
x[1], y[0] = f(0), f(1)
check(x, 2, 1, 3)
}
func p4() {
x := []int{1, 2, 3}
y := x
gx = x
x[1], y[0] = gx[0], gx[1]
check(x, 2, 1, 3)
}
func p5() {
x := []int{1, 2, 3}
y := x
p := &x[0]
q := &x[1]
*p, *q = x[1], y[0]
check(x, 2, 1, 3)
}
func p6() {
x := 1
y := 2
z := 3
px := &x
py := &y
*px, *py = y, x
check3(x, y, z, 2, 1, 3)
}
func f1(x, y, z int) (xx, yy, zz int) {
return x, y, z
}
func f2() (x, y, z int) {
return f1(2, 1, 3)
}
func p7() {
x, y, z := f2()
check3(x, y, z, 2, 1, 3)
}
func p8() {
m := make(map[int]int)
m[0] = len(m)
if m[0] != 0 {
panic(m[0])
}
}
// Issue #13433: Left-to-right assignment of OAS2XXX nodes.
func p9() {
var x bool
// OAS2FUNC
x, x = fn()
checkOAS2XXX(x, "x, x = fn()")
// OAS2RECV
var c = make(chan bool, 10)
c <- false
x, x = <-c
checkOAS2XXX(x, "x, x <-c")
// OAS2MAPR
var m = map[int]bool{0: false}
x, x = m[0]
checkOAS2XXX(x, "x, x = m[0]")
// OAS2DOTTYPE
var i interface{} = false
x, x = i.(bool)
checkOAS2XXX(x, "x, x = i.(bool)")
}
//go:noinline
func fn() (bool, bool) { return false, true }
// checks the order of OAS2XXX.
func checkOAS2XXX(x bool, s string) {
if !x {
fmt.Printf("%s; got=(false); want=(true)\n", s)
panic("failed")
}
}