http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57858
--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Actually, it isn't vectorized at all, because PRE attempts to be smart, figures out that for the first iteration of the loop it can avoid computing the sqrt because the result will be one, and moves thus the sqrt call into the latch, but we can't vectorize any loops that have non-empty latches. So, either the vectorizer would need to undo this transformation, or PRE not do it at all, or arrange for it to be done only after vectorizations. Richard, any thoughts on this?
