[Bug tree-optimization/113896] [12 Regression] Assigning array elements in the wrong order after floating point optimization since r12-8841

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113896

--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:2f16c53558d01135f0f78cf78a2f722b774684d7

commit r12-10155-g2f16c53558d01135f0f78cf78a2f722b774684d7
Author: Richard Biener <rguenther@suse.de>
Date:   Tue Feb 13 13:43:44 2024 +0100

    tree-optimization/113896 - reduction of permuted external vector

    The following fixes eliding of the permutation of a BB reduction
    of an existing vector which breaks materialization of live lanes
    as we fail to permute the SLP_TREE_SCALAR_STMTS vector.

            PR tree-optimization/113896
            * tree-vect-slp.cc (vect_optimize_slp): Permute
            SLP_TREE_SCALAR_STMTS when eliding a permuation in a
            VEC_PERM node we need to preserve because it wraps an
            extern vector.

            * g++.dg/torture/pr113896.C: New testcase.