Why is this statement with bitwise operators the same as this if statement?

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How is if-statement and bitwise operations same in this example? 4 answers

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It first converts the comparison to subtraction with 128.

Then the sign of the result (whether subtracting went below 128) is expanded to either all zeroes or all ones, which is and ed to the value being added, zeroing it out if the result of the subtraction was negative.

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