https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114121
--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> --- And it works even with -O2 -ftree-loop-vectorize -fno-tree-slp-vectorize and doesn't work with -O2 -fno-tree-loop-vectorize -ftree-slp-vectorize so will need to look at what SLP vectorization does here.
