https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103641
--- Comment #25 from Richard Biener <rguenth at gcc dot gnu.org> --- diff --git a/gcc/tree-vect-patterns.cc b/gcc/tree-vect-patterns.cc index bea04992160..856b8bd222e 100644 --- a/gcc/tree-vect-patterns.cc +++ b/gcc/tree-vect-patterns.cc @@ -3050,13 +3050,13 @@ vect_synth_mult_by_constant (vec_info *vinfo, tree op, tree val, /* Use MAX_COST here as we don't want to limit the sequence on rtx costs. The vectorizer's benefit analysis will decide whether it's beneficial to do this. */ - bool possible = choose_mult_variant (mode, hwval, &alg, + tree vectype = get_vectype_for_scalar_type (vinfo, multtype); + + bool possible = choose_mult_variant (TYPE_MODE (vectype), hwval, &alg, &variant, MAX_COST); if (!possible) return NULL; - tree vectype = get_vectype_for_scalar_type (vinfo, multtype); - if (!vectype || !target_supports_mult_synth_alg (&alg, variant, vectype, synth_shift_p)) improves compile-time from 29s to 12s for the testcase (-O0 compiled cc1 with checking enabled ...), I didn't analyze what the actual difference in the chosen multiplication sequence is of course.