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Question

What do compilers usually do when the multiplier is a constant?

a.

Use MUL/IMUL instruction

b.

Use SHL and ADD instructions

c.

Use LEA instruction

d.

None of the above

Posted under Reverse Engineering

Answer: (b).Use SHL and ADD instructions Explanation:When the multiplier is a constant, compilers usually avoid using MUL/IMUL instructions and instead use SHL and ADD instructions.

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Q. What do compilers usually do when the multiplier is a constant?

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