ASM_FMT_B2
op = ASM_OP_BR_CLOOP, fmt = ASM_FMT_B2;
op = ASM_OP_BR_CEXIT, fmt = ASM_FMT_B2;
op = ASM_OP_BR_CTOP, fmt = ASM_FMT_B2;
case ASM_FMT_B2: /* 0 dst */