https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81616
--- Comment #49 from Jan Hubicka <hubicka at ucw dot cz> --- > matrix.c is still needing additional options to get the best out of the Ryzen > processor. But is better than before (223029 clocks vs 371978 originally), > but 122677 is achievable with the right options. However the same can also be Aha, for ryzen we would still benefit from 256 vectorization. It is not a win overall and it will need bigger surgey to vectorizer to implement properly, so that will wait for next stage1 unfortunately. This is the gap between -march=znver1 -mtune=generic and -march=znver1, so about 17% Concerning your options -mprefer-vector-width=none -mno-fma -mno-avx2 -O3 With Martin's patch in -mno-fma should no longer have effect here. Not sure why -mno-avx2 would be a win either. We originally introduced it to disable scatter/gather in the other benchmark but that one is solved too. Do those two option still improve the scores for you. It is alaso mystery to me why -march=ivybridge would benefit anything as the isa is more or less supperset of znver. I will try to find more to check more. Honza
