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Question

What is the Zero Flag used for in IA-32 code?

a.

Comparing two operands and testing whether they are equal.

b.

Setting the value of the most significant bit of the result.

c.

Reporting the binary parity of the lower 8 bits of certain arithmetic results.

d.

None of the above.

Posted under Reverse Engineering

Answer: (a).Comparing two operands and testing whether they are equal. Explanation:The Zero Flag is set when the result of an arithmetic operation is zero, and it is cleared if the result is nonzero. ZF is used in quite a few different situations in IA-32 code, but probably one of the most common uses it has is for comparing two operands and testing whether they are equal.

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Q. What is the Zero Flag used for in IA-32 code?

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