https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103116
--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-12 branch has been updated by Richard Biener <rgue...@gcc.gnu.org>: https://gcc.gnu.org/g:fdf50499a40399a48ac5e5d521ef93ed302be157 commit r12-8405-gfdf50499a40399a48ac5e5d521ef93ed302be157 Author: Richard Biener <rguent...@suse.de> Date: Wed May 4 10:43:07 2022 +0200 tree-optimization/103116 - SLP permutes and peeling for gaps The testcase shows that we can end up with a contiguous access across loop iterations but by means of permutations the elements accessed might only cover parts of a vector. In this case we end up with GROUP_GAP == 0 but still need to avoid accessing excess elements in the last loop iterations. Peeling for gaps is designed to cover this but a single scalar iteration might not cover all of the excess elements. The following ensures peeling for gaps is done in this situation and when that isn't sufficient because we need to peel more than one iteration (gcc.dg/vect/pr103116-2.c), fail the SLP vectorization. 2022-05-04 Richard Biener <rguent...@suse.de> PR tree-optimization/103116 * tree-vect-stmts.cc (get_group_load_store_type): Handle the case we need peeling for gaps even though GROUP_GAP is zero. * gcc.dg/vect/pr103116-1.c: New testcase. * gcc.dg/vect/pr103116-2.c: Likewise. (cherry picked from commit 52b7b86f8c72eb19e637f1e72ffd10f39b8cb829)
