https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107250
--- Comment #3 from Alexander Monakov <amonakov at gcc dot gnu.org> --- Well, obviously because in one function both 'f' and 'tmp' are live across the call, and in the other function only 'f' is live across the call. The difference is literally pushing one register vs. two registers, plus extra 8 bytes to preserve 16-byte ABI alignment.
