[Bug tree-optimization/123315] [16 Regression] ICE during GIMPLE pass, Segmentation fault, at tree-vect-loop.cc:10694

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123315

Jeffrey A. Law <law at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Blocks|120763                      |
                 CC|                            |rguenth at gcc dot gnu.org

--- Comment #3 from Jeffrey A. Law <law at gcc dot gnu.org> ---
Bisected to:

ec1e49540f1df9917fdcd6c37c35583672ec613d is the first bad commit
commit ec1e49540f1df9917fdcd6c37c35583672ec613d
Author: Richard Biener <rguenther@suse.de>
Date:   Fri Nov 14 14:07:01 2025 +0100

    Decide on LOOP_VINFO_USING_SELECT_VL_P after determining partial vectors

    The following makes us decide on partial vectors first so we can
    use LOOP_VINFO_USING_PARTIAL_VECTORS_P to decide on a decrementing IV
    and LOOP_VINFO_USING_SELECT_VL_P as followup.

            * tree-vect-loop.cc (vect_determine_partial_vectors_and_peeling):
            Remove resetting of LOOP_VINFO_USING_SELECT_VL_P.
            (vect_analyze_loop_2): Decide on partial vectors before
            deciding on decrementing IV or .SELECT_VL usage.

I haven't done any further investigation.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120763
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