[Bug fortran/65450] [4.9/5 Regression]: Unaligned access with -O3 -mtune=k8

[jakub at gcc dot gnu.org]

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.