https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102659
--- Comment #7 from CVS 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:9b2ad21ab3ebc21a3408108327fa1a7cbedaf217 commit r12-4398-g9b2ad21ab3ebc21a3408108327fa1a7cbedaf217 Author: Richard Biener <rguent...@suse.de> Date: Thu Oct 14 09:00:25 2021 +0200 tree-optimization/102659 - really avoid undef overflow in if-conversion This plugs the remaining hole of POINTER_PLUS_EXPR with undefined overflow. Unfortunately we have to go through some lengths to not put invariant conversions into the loop body since that confuses the vectorizers gather/scatter discovery which relies on identifying an invariant component of plus and minus expressions. We can emit those in the loop preheader but then we have to accept that being non-empty when looking for the LOOP_VECTORIZED internal function call in the vectorizer. 2021-10-14 Richard Biener <rguent...@suse.de> PR tree-optimization/102659 * tree-if-conv.c (if_convertible_gimple_assign_stmt_p): Also rewrite pointer typed undefined overflow operations. (predicate_statements): Likewise. Make sure to emit invariant conversions in the preheader. * tree-vectorizer.c (vect_loop_vectorized_call): Look through non-empty preheaders. * tree-data-ref.c (dr_analyze_indices): Strip useless conversions to the MEM_REF base type.
