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题目: 判断ZF, PF, SF的值
最后一个没有看懂, al的最高位为1, SF为什么会等于0呢, 是因为mul指令的结果存放在ax所以最后判断的时候是看ax的最高位吗
- code segment
- start:
- sub al,al ; 结果:00000000b ZF = 1, PF = 1, SF = 0
- mov al,1 ; 结果:00000001b ZF = 1, PF = 1, SF = 0
- push ax ; 结果:00000001b ZF = 1, PF = 1, SF = 0
- pop bx ; 结果:00000001b ZF = 1, PF = 1, SF = 0
- add al,bl ; 结果:00000010b ZF = 0, PF = 0, SF = 0
- add al,10 ; 结果:00001100b ZF = 0, PF = 1, SF = 0
- mul al ; 结果:10010000b ZF = 0, PF = 1, SF = 0
- mov ax, 4c00h
- int 21h
- code ends
- end start
复制代码
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