https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103665
--- Comment #1 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jan Hubicka <hubi...@gcc.gnu.org>: https://gcc.gnu.org/g:e93809f62363ba4b233858005aef652fb550e896 commit r12-5915-ge93809f62363ba4b233858005aef652fb550e896 Author: Jan Hubicka <j...@suse.cz> Date: Sun Dec 12 11:38:13 2021 +0100 Terminate BB analysis on NULL memory access in ipa-pure-const and ipa-modref As discussed in the PR, we miss some optimization becuase gimple-ssa-isolate-paths turns NULL memory accesses to volatile and adds __builtin_trap after them. This is seen as a side-effect by IPA analysis and additionally the (fully unreachable) builtin_trap is believed to load all global memory. I think we should think of less intrusive gimple representation of this, but it is also easy enough to special case that in IPA analysers as done in this patch. This is a win even if we improve the representation since gimple-ssa-isolate-paths is run late and this way we improve optimization early. This affects 1623 functions during cc1plus link. Bootstrapped/regtested x86_64-linux, comitted. gcc/ChangeLog: 2021-12-12 Jan Hubicka <hubi...@ucw.cz> PR ipa/103665 * ipa-modref.c (modref_access_analysis::analyze): Terminate BB analysis on NULL memory access. * ipa-pure-const.c (analyze_function): Likewise.
