https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126977
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- There's also CLZ and friends with the value-at-zero and other magic IFNs (.DEFERRED_INIT comes to my mind, as well as the BIAS value for vector load/stores). Maybe some internal_flag_arg_p (code_helper, unsigned) helper would be useful. "internal flag" as in something that isn't a runtime value.
