https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111444
--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> --- OK, so the issue is that we're recording the IPA result with the wrong VUSE since we're calling vn_reference_lookup_2 with !data->last_vuse_ptr but data->finish (vr->set, vr->base_set, v) inserts a hashtable entry with data->last_vuse. Note it's somewhat unexpected that vn_reference_lookup_2 performs hashtable insertion which is what causes the issue. It's also not as easy as using the updated vuse since if we're coming from translation through a memcpy that would be wrong. In fact we probably want to avoid doing any insertion if theres sth fishy going on (!data->last_vuse_ptr). The best fix would likely be to pre-insert all the IPA-CP known constants instead of trying to discover them "late". I'm testing the easy fix for now.
