The question is ill-posed: MFENCE does not equal LFENCE + SFENCE. LFENCE orders only loads with respect to other loads; SFENCE orders only stores with respect

The question is ill-posed: MFENCE does not equal LFENCE + SFENCE. LFENCE orders only loads with respect to other loads; SFENCE orders only stores with respect to other stores; but MFENCE orders not only loads w/r/t loads and stores w/r/t stores, but also loads w/r/t stores (and vice versa).