[Bug tree-optimization/57558] Issue with number of iterations calculation

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57558

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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             Blocks|                            |53947

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
That's because the first variant can loop infinitely for n == ULONG_MAX
and that "infinite" cannot be represented using new induction variable
as the vectorizer wants to.  Well, not easily at least.