https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99407
--- Comment #3 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:4bdf739f835520ccbc433dc9eac461895741f317 commit r13-2769-g4bdf739f835520ccbc433dc9eac461895741f317 Author: Richard Biener <rguent...@suse.de> Date: Thu Sep 22 09:40:40 2022 +0200 tree-optimization/99407 - DSE with data-ref analysis The following resolves the issue that DSE cannot handle references with variable offsets well when identifying possible uses of a store. Instead of just relying on ref_maybe_used_by_stmt_p we use data-ref analysis, making sure to perform that at most once per stmt. The new mode is only exercised by the DSE pass before loop optimization as specified by a new pass parameter and when expensive optimizations are enabled, so it's disabled below -O2. PR tree-optimization/99407 * tree-ssa-dse.cc (dse_stmt_to_dr_map): New global. (dse_classify_store): Use data-ref analysis to disambiguate more uses. (pass_dse::use_dr_analysis_p): New pass parameter. (pass_dse::set_pass_param): Implement. (pass_dse::execute): Allocate and deallocate dse_stmt_to_dr_map. * passes.def: Allow DR analysis for the DSE pass before loop. * gcc.dg/vect/tsvc/vect-tsvc-s243.c: Remove XFAIL.