[Bug tree-optimization/77689] Missing vectorization lead to huge performance loss

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77689

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Markus Trippelsdorf from comment #2)
> Clang is pretty impressive using libc++ and -Ofast:

Looks like they can remove all stores from the loop.  Though it does not remove
the empty loop afterwards though.