languages/go
languages/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-09-06 00:19:45 +00:00
Code Issues Packages Projects Releases Wiki Activity

cmd/compile: remove bug workarounds in prove's loop inversion

Browse source 
I wrote theses checks because I got bad panics on some innocent functions,
turns out I was working around #63955 but I was not aware of that at the time.

The proper fix was included in CL 539977 this is now doing nothing.

Change-Id: I89329329933527b6f3cb817dc1e039a38f58da9a
Reviewed-on: https://go-review.googlesource.com/c/go/+/560975
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
This commit is contained in:
Jorropo 2024-02-03 09:06:30 +01:00 committed by Gopher Robot
parent b159c99eb7
commit ff35c382eb
1 changed files with 2 additions and 19 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

21
src/cmd/compile/internal/ssa/prove.go
View file

@ -878,34 +878,17 @@ func prove(f *Func) {
continue
}
header := ind.Block
check := header.Controls[0]
if check == nil {
// we don't know how to rewrite a loop that not simple comparison
continue
}
switch check.Op {
case OpLeq64, OpLeq32, OpLeq16, OpLeq8,
OpLess64, OpLess32, OpLess16, OpLess8:
default:
// we don't know how to rewrite a loop that not simple comparison
continue
}
if !((check.Args[0] == ind && check.Args[1] == end) ||
(check.Args[1] == ind && check.Args[0] == end)) {
// we don't know how to rewrite a loop that not simple comparison
continue
}
if end.Block == ind.Block {
// we can't rewrite loops where the condition depends on the loop body
// this simple check is forced to work because if this is true a Phi in ind.Block must exists
continue
}
check := ind.Block.Controls[0]
// invert the check
check.Args[0], check.Args[1] = check.Args[1], check.Args[0]
// invert start and end in the loop
// swap start and end in the loop
for i, v := range check.Args {
if v != end {
continue