https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113734
--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
Another bug in the dependence checking code is
if (dr_may_alias_p (dr_ref, dr_read, loop_nest))
which will end up using TBAA - dr_may_alias_p doesn't think you are ever
going to move stores down across loads. To verify if that's possible
you need to use
if (dr_may_alias_p (dr_read, dr_ref, loop_nest))
instead.
Note there's still my very original review consideration that you move
stmts out-of-order but the main dependence checking the vectorizer does
assumes the stores and loads appear in their original order. I'm not
sure whether with the above we prove this doesn't matter.
