https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98986
--- Comment #5 from Segher Boessenkool <segher at gcc dot gnu.org> --- (In reply to rsand...@gcc.gnu.org from comment #3) > FWIW, another similar thing I've wanted in the past is to try > recognising multiple possible constants in an (and X (const_int N)) > when X is known to have some bits clear. Often we try to make N contain > as few bits as possible, but that can give worse results than a fuller mask. This could be done in the target machine description, where it makes a lot more sense to do anyway, *if* nonzero_bits was generally usable there. I have Plans for that for GCC 12, but don't depend on it please :-)