https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80355
--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:50b5877925ef5ae8e9f913d6d2b5ce0204ebc588 commit r12-2837-g50b5877925ef5ae8e9f913d6d2b5ce0204ebc588 Author: Jakub Jelinek <ja...@redhat.com> Date: Tue Aug 10 12:38:00 2021 +0200 i386: Allow some V32HImode and V64QImode permutations even without AVX512BW [PR80355] When working on the PR, I've noticed we generate terrible code for V32HImode or V64QImode permutations for -mavx512f -mno-avx512bw. Generally we can't do much with such permutations, but since PR68655 we can handle at least some, those expressible using V16SImode or V8DImode permutations, but that wasn't reachable, because ix86_vectorize_vec_perm_const didn't even try, it said without TARGET_AVX512BW it can't do anything, and with it can do everything, no d.testing_p attempts. This patch makes it try it for TARGET_AVX512F && !TARGET_AVX512BW. The first hunk is to avoid ICE, expand_vec_perm_even_odd_1 asserts d->vmode isn't V32HImode because expand_vec_perm_1 for AVX512BW handles already all permutations, but when we let it through without !TARGET_AVX512BW, expand_vec_perm_1 doesn't handle it. If we want, that hunk can be dropped if we implement in expand_vec_perm_even_odd_1 and its helper the even permutation as vpmovdw + vpmovdw + vinserti64x4 and odd permutation as vpsrld $16 + vpsrld $16 + vpmovdw + vpmovdw + vinserti64x4. 2021-08-10 Jakub Jelinek <ja...@redhat.com> PR target/80355 * config/i386/i386-expand.c (expand_vec_perm_even_odd): Return false for V32HImode if !TARGET_AVX512BW. (ix86_vectorize_vec_perm_const) <case E_V32HImode, case E_V64QImode>: If !TARGET_AVX512BW and TARGET_AVX512F and d.testing_p, don't fail early, but actually check the permutation. * gcc.target/i386/avx512f-pr80355-2.c: New test.