https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116460
--- Comment #23 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:172637cf0d9b7b2798f83b9c5f9598b449675cb0 commit r15-3210-g172637cf0d9b7b2798f83b9c5f9598b449675cb0 Author: Richard Biener <rguent...@suse.de> Date: Mon Aug 26 13:50:00 2024 +0200 tree-optimization/116460 - ICE with DCE in forwprop The following avoids removing stmts with defs that might still have uses in the IL before calling simple_dce_from_worklist which might remove those as that will wreck debug stmt generation. Instead first perform use-based DCE and then remove stmts which may have uses in code that CFG cleanup will remove. This requires tracking stmts in to_remove by their SSA def so we can check whether it was removed before without running into the issue that PHIs can be ggc_free()d upon removal. So this adds to_remove_defs in addition to to_remove which has to stay to track GIMPLE_NOPs we want to elide. PR tree-optimization/116460 * tree-ssa-forwprop.cc (pass_forwprop::execute): First do simple_dce_from_worklist and then remove stmts in to_remove. Track defs to be removed in to_remove_defs. * g++.dg/torture/pr116460.C: New testcase.
