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Question

How does the compiler determine which case block to jump into when using a tree-based n-way conditional?

a.

By comparing the provided value against each one of the possible cases in runtime.

b.

By subtracting certain values from the original value passed to the conditional block, constantly checking if the result is zero.

c.

By using an immediate, hard-coded address for the jump.

d.

By including a counter to control the number of iterations.

Posted under Reverse Engineering

Answer: (b).By subtracting certain values from the original value passed to the conditional block, constantly checking if the result is zero. Explanation:The compiler typically starts with the original value passed to the conditional block and gradually subtracts certain values from it (these are usually the case block values), constantly checking if the result is zero. This is simply an efficient way to determine which case block to jump into using the smallest possible code.

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Q. How does the compiler determine which case block to jump into when using a tree-based n-way conditional?

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