https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109592
--- Comment #6 from Jeffrey A. Law <law at gcc dot gnu.org> --- I would still rather not introduce special cases for SUBREGs if we can avoid it. I think the question remains whether or not patching simplify-rtx's canonicalize_shift is sufficient to fix this problem (perhaps with the adjustment to fwprop as well). If they are, then they would be much preferred over the original patch which special cased SUBREGs.
