https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119960
--- Comment #8 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Richard Biener <rgue...@gcc.gnu.org>: https://gcc.gnu.org/g:51ba233fe2db562390a6e0a3618420889761bc77 commit r16-305-g51ba233fe2db562390a6e0a3618420889761bc77 Author: Richard Biener <rguent...@suse.de> Date: Tue Apr 29 13:23:41 2025 +0200 tree-optimization/119960 - failed external SLP promotion The following addresses a too conservative sanity check of SLP nodes we want to promote external. The issue lies in code generation for such external which relies on get_later_stmt to figure an insert location. But get_later_stmt relies on the ability to totally order stmts, specifically implementation-wise that they are all from the same BB, which is what is verified at the moment. The patch changes this to require stmts to be orderable by dominance queries. For simplicity and seemingly enough for the testcase in PR119960, this handles the case of two distinct BBs. PR tree-optimization/119960 * tree-vect-slp.cc (vect_slp_can_convert_to_external): Handle cases where defs from multiple BBs are ordered by their dominance relation. * gcc.dg/vect/bb-slp-pr119960-1.c: New testcase.
