https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109849
--- Comment #48 from Richard Biener <rguenth at gcc dot gnu.org> --- OK, so 'location' is relevant for refs like *q_19, and indicates the value of 'q_19' which would need to be remembered along with the stored value. I had added gcc.dg/torture/20211118-1.c for this which fails when allowing CONSTANT_CLASS_P values (so values we can remember). Unfortunately the clobber that's relevant here suffers from the same issue - we do not handle recovering the location to clobber for the store to be materialized on the alternate edge. So the only simple improvement I can offer is when the location has no loop variant components. A further enhancement would be to record the store location in another IV so we can properly re-materialize the last store(s). Profitability would tank, of course, and for clobbers this might be not a good idea anyway. For clobbers to loop variant addresses we could also simply decide to drop them alltogether (we'd have to drop them in-loop, of course).
