https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121686
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
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Keywords| |missed-optimization
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
So it's
t.c:8:14: note: Analyze phi: k_17 = PHI <3(17), _52(14)>
t.c:8:14: missed: intermediate value used outside loop.
that we now fail to vectorize at all, with GCC 15 and forced SLP it
runs into hybrid detection (which is now removed, thus wrong-code),
failing to vectorize this. With classical vect we recognize this
as a vectorizable recurrence.
I have a patch.
