https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109907
--- Comment #8 from Georg-Johann Lay <gjl at gcc dot gnu.org> --- avr.md has this: > ;; ??? do_store_flag emits a hard-coded right shift to extract a bit without > ;; even considering rtx_costs, extzv, or a bit-test. See PR55181 for an > example. And I already tried to work around it in that PR, but forgot about it...