On Wed, Apr 05, 2023 at 09:07:30AM -0600, Jeff Law wrote: > On 4/5/23 08:21, Segher Boessenkool wrote: > >On Wed, Mar 29, 2023 at 07:48:00AM -0600, Jeff Law wrote: > >>So as mentioned in the PR the underlying issue here is combine changes > >>the form of an existing insn, but fails to force re-recognition. As a > >>result other parts of the compiler blow up. > > > >[snip] > > > >>The fix is trivial, reset the INSN_CODE to force re-recognition in the > >>case where try_combine fails. > > > >Thanks for the clear explanation! Okay for trunk. Also okay for all > >backports (after a week or so on trunk). > Thanks. I haven't seen this on any of the release branches, so no > strong opinions on backporting at this time. It's a pretty narrow bug > (no surprise given its been latent for something like 10 years).
Right. But it seems to me it has been there all those years? Does the new testcase fail on older branches? Even if not, it seems clear it is wrong on the older branches as well! But if you think it is too dangerous to backport, let's not. Thanks, Segher
