https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120941
--- Comment #19 from Filip Kastl <pheeck at gcc dot gnu.org> --- Well, if you want to reproduce the lbm slowdown, you need a Zen2 or Zen5 machine. I'm not sure how I would produce a testcase that would also uncover the slowdown on other microarchitectures, sorry. If I understand correctly, you have a Zen3 machine and don't have a Zen2 or Zen5 machine, right? Then there is also the bwaves slowdown on Zen3. It also bisects to your commit so it might be caused by the same problem. To reproduce that, compile 2017 bwaves_r with -Ofast -march=native with r16-1644-gaba3b9d3a48a07 and with the previous commit and you should get ~10% slowdown. Or use 2006 bwaves also with -Ofast -march=native and you should get ~5% slowdown.
