[Bug tree-optimization/126997] [17 Regression] ICE exact_div, at poly-int.h:2179 with SLP vectorisation

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126997

--- Comment #3 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:66ed104db50c639c79e7ba2826ccd6df41cb37c1

commit r17-3584-g66ed104db50c639c79e7ba2826ccd6df41cb37c1
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Aug 24 11:24:57 2026 +0200

    tree-optimization/126997 - hoist invariants after unswitching

    The following makes sure to hoist loop invariants after unswitching
    a loop.  Invariant stmts in a loop can make vectorization less
    effective and now confuse it.  While if-conversion moves invariants
    already, when there's nothing to if-convert this isn't done.  This
    follows what loop interchange and unroll-and-jam already do.

            PR tree-optimization/126997
            * tree-ssa-loop-unswitch.cc (tree_ssa_unswitch_loops):
            Perform invariant motion when we unswitched a loop.

            * gcc.dg/torture/pr126997.c: New testcase.