_nn_divrem_unshifted
ret = _nn_divrem_unshifted(q, &r, a, b_norm, v, cnt); EG(ret, err);
ret = _nn_divrem_unshifted(q, r, a, b, v, cnt);
ret = _nn_divrem_unshifted(q, r, a, &b_normalized, v, cnt);