[Bug middle-end/121509] [16 Regression] runtime differences with -march=znver3

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121509

--- Comment #9 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:c5dab6fb402c93a92f6aa808c43956dfb9328190

commit r16-3162-gc5dab6fb402c93a92f6aa808c43956dfb9328190
Author: Richard Biener <rguenther@suse.de>
Date:   Tue Aug 12 09:51:54 2025 +0200

    tree-optimization/121509 - failure to detect unvectorizable loop

    With the hybrid stmt detection no longer working as a gate-keeper
    to detect unhandled stmts we have to, and can, detect those earlier.
    The appropriate place is vect_mark_stmts_to_be_vectorized where
    for trivially relevant PHIs we can stop analyzing when the PHI
    wasn't classified as a known def during vect_analyze_scalar_cycles.

            PR tree-optimization/121509
            * tree-vect-stmts.cc (vect_mark_stmts_to_be_vectorized):
            Fail early when we detect a relevant but not handled PHI.

            * gcc.dg/vect/pr121509.c: New testcase.