https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126306
--- Comment #2 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Richard Biener <[email protected]>: https://gcc.gnu.org/g:bca597522679903c66f28afff49971663a37ab37 commit r17-4410-gbca597522679903c66f28afff49971663a37ab37 Author: Richard Biener <[email protected]> Date: Fri Sep 18 09:18:15 2026 +0200 tree-optimization/126306 - delay BB vectorization SLP discovery soft fail The following delays SLP discovery failure due to required unrolling when doing BB vectorization to after we have also analyzed the defs which can provide indication for where to best split the group. This does not add meaningful to compile-time or eats from the SLP discovery budget and can handle simple cases as shown in the testcase. The case in the PR requires a followup which does have such downside. PR tree-optimization/126306 * tree-vect-slp.cc (vect_build_slp_tree_1): Remove soft-failing. (vect_build_slp_tree_2): Add soft-failing here, delayed to after vect_get_and_check_slp_defs. (vect_get_and_check_slp_defs): When we'll soft-fail do not fall back to vect_external_def on mismatches. * gcc.dg/vect/bb-slp-pr126306-1.c: New testcase.
