https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120219
Filip Kastl <pheeck at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|[16 Regression] ~11% |[16 Regression] ~11%
|slowdown of 548.exchange2_r |slowdown of 548.exchange2_r
|on AMD Zen |on x86_64
--- Comment #2 from Filip Kastl <pheeck at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #1)
> There was a similar jump before, so maybe we're just hitting that very thing
> again? Has that been filed/bisected?
That's pr119919. Could be the same thing. pr119919 is caused by one of
Honza's recent vectorizer costing commits. As far as I understand, Andrew's
commit doesn't touch vectorizer directly, but I guess that loop optimizations
and the vectorizer are related.
Btw, I've just noticed that this slowdown also happened on Intel:
-O2 -march=generic -flto Intel Ice Lake (3rd generation Xeon)
https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=800.407.0
