[Bug tree-optimization/95570] vect: ICE: Segmentation fault in vect_loop_versioning

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95570
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Sandiford <rsand...@gcc.gnu.org>:

https://gcc.gnu.org/g:d30846a02eb9ea43b61311e74fbf05692ffefba2

commit r11-1283-gd30846a02eb9ea43b61311e74fbf05692ffefba2
Author: Fei Yang <felix.y...@huawei.com>
Date:   Fri Jun 12 11:37:00 2020 +0100

    vect: Fix an ICE in vect_loop_versioning [PR95570]

    In the test case for PR95570, the only data reference in the loop is a
    gather-statter access.  Scalar evolution analysis for this data reference
    failed, so DR_STEP is NULL_TREE.  This leads to the segmentation fault.
    We should filter out scatter-gather access in
vect_enhance_data_refs_alignment.

    2020-06-12  Felix Yang  <felix.y...@huawei.com>

    gcc/
            PR tree-optimization/95570
            * tree-vect-data-refs.c (vect_relevant_for_alignment_p): New
function.
            (vect_verify_datarefs_alignment): Call it to filter out data
references
            in the loop whose alignment is irrelevant.
            (vect_get_peeling_costs_all_drs): Likewise.
            (vect_peeling_supportable): Likewise.
            (vect_enhance_data_refs_alignment): Likewise.

    gcc/testsuite/

            PR tree-optimization/95570
            * gcc.dg/vect/pr95570.c: New test.