https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78855
Uroš Bizjak <ubizjak at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |WAITING
Last reconfirmed| |2016-12-19
Ever confirmed|0 |1
--- Comment #1 from Uroš Bizjak <ubizjak at gmail dot com> ---
(In reply to Peter Cordes from comment #0)
> The penalty for doing the compare a couple instructions later on CPUs that
> don't support fusion might increasing the mispredict penalty by a couple
> cycles, I think. So I don't think we'd be hurting Atom a lot to help more
> common CPUs a little.
We do have FIXMEs to enable X86_TUNE_FUSE_CMP_AND_BRANCH for generic (and
intel) tunes. But the default for generic won't be changed until there are
benchmark results that confirm your suggestions.
