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| author | Michael Munday <mike.munday@ibm.com> | 2017-03-29 14:01:41 -0400 |
|---|---|---|
| committer | Michael Munday <mike.munday@ibm.com> | 2017-08-24 16:53:56 +0000 |
| commit | 744ebfde0460e1d8fff10672e4d1e8d9ece52556 (patch) | |
| tree | 30f9eca8178f7ce2b7534ab394e0e1dac4e42e60 /test/live2.go | |
| parent | 18b48afec9be0a1da4b23bebace0dc9f081dcee1 (diff) | |
| download | go-744ebfde0460e1d8fff10672e4d1e8d9ece52556.tar.gz go-744ebfde0460e1d8fff10672e4d1e8d9ece52556.zip | |
cmd/compile: eliminate stores to unread auto variables
This is a crude compiler pass to eliminate stores to auto variables
that are only ever written to.
Eliminates an unnecessary store to x from the following code:
func f() int {
var x := 1
return *(&x)
}
Fixes #19765.
Change-Id: If2c63a8ae67b8c590b6e0cc98a9610939a3eeffa
Reviewed-on: https://go-review.googlesource.com/38746
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Diffstat (limited to 'test/live2.go')
| -rw-r--r-- | test/live2.go | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/test/live2.go b/test/live2.go index 6138d369c9..5c5706d225 100644 --- a/test/live2.go +++ b/test/live2.go @@ -14,6 +14,9 @@ package main func printnl() +//go:noescape +func useT40(*T40) + type T40 struct { m map[int]int } @@ -27,7 +30,7 @@ func newT40() *T40 { func bad40() { t := newT40() // ERROR "live at call to makemap: .autotmp_[0-9]+ ret$" printnl() // ERROR "live at call to printnl: .autotmp_[0-9]+ ret$" - _ = t + useT40(t) // ERROR "live at call to useT40: .autotmp_[0-9]+ ret$" } func good40() { @@ -35,5 +38,5 @@ func good40() { ret.m = make(map[int]int) // ERROR "live at call to makemap: .autotmp_[0-9]+ ret$" t := &ret printnl() // ERROR "live at call to printnl: .autotmp_[0-9]+ ret$" - _ = t + useT40(t) // ERROR "live at call to useT40: .autotmp_[0-9]+ ret$" } |