https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65450
--- Comment #13 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Created attachment 35047 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35047&action=edit gcc5-pr65450.patch Fix that passed bootstrap/regtest on x86_64-linux and i686-linux. It is I think conservatively correct, on the other side we don't have any ccp pass after vectorization that could recompute that info, only vrp2 which doesn't do zero bits computation, so perhaps we should try harder.