_fix_scalar_msb
ret = _fix_scalar_msb(&x_, q, &x_); EG(ret, err);
ret = _fix_scalar_msb(&k_, q, &k_); EG(ret, err);
ret = _fix_scalar_msb(&k_, q, &k_); EG(ret, err);
ret = _fix_scalar_msb(&k_, q, &k_); EG(ret, err);
ret = _fix_scalar_msb(&k_, q, &k_); EG(ret, err);