What is the ZF behavior for the imul instruction? [duplicate]

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ZF not set as a result of MUL instruction in assembly language (1 answer)

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The instruction set reference says that the ZF is undefined for the imul instruction. So what happens to the ZF if I multiply a value in a register by an immediate value of 0x0?

Answer 1

Undefined means that result can be anything and none of the values matter anything.