[Bug tree-optimization/111387] [13 Regression] ICE on valid code at -O2 and -O3: verify_ssa failed

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111387

--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:1990e6544b9f0db39c470b999c32d2ecdd419f46

commit r13-10355-g1990e6544b9f0db39c470b999c32d2ecdd419f46
Author: Richard Biener <rguenther@suse.de>
Date:   Wed Sep 13 11:04:31 2023 +0200

    tree-optimization/111387 - BB SLP and irreducible regions

    When we split an irreducible region for BB vectorization analysis
    the defensive handling of external backedge defs in
    vect_get_and_check_slp_defs doesn't work since that relies on
    dominance info to identify a backedge.  The testcase also shows
    we are iterating over the function in a sub-optimal way which is
    why we split the irreducible region in the first place.  The fix
    is to mark backedges and use EDGE_DFS_BACK to identify them.

            PR tree-optimization/111387
            * tree-vect-slp.cc (vect_get_and_check_slp_defs): Check
            EDGE_DFS_BACK when doing BB vectorization.
            (vect_slp_function): Mark backedges.

            * gcc.dg/torture/pr111387.c: New testcase.