[Bug tree-optimization/106293] [13/14 Regression] 456.hmmer at -Ofast -march=native regressed by 19% on zen2 and zen3 in July 2022

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106293

--- Comment #25 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jan Hubicka from comment #24)
> g:2e93b92c1ec5fbbbe10765c6e059c3c90d564245 fixes the profile update after
> cancelled distribution. However it does not help hmmer since we actually
> vectorize that loop iterating 0 times.  We need to figure out proper
> iteration count for that and convince loop distribution and vectorizer to do
> nothing on it.

or use a smaller VF?  I doubt the scalar loop iterates zero times?