Is < faster than <=?

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孤城傲影
孤城傲影 2020-11-22 13:43

Is if( a < 901 ) faster than if( a <= 900 ).

Not exactly as in this simple example, but there are slight performance changes on loop

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  •  刺人心
    刺人心 (楼主)
    2020-11-22 13:56

    They have the same speed. Maybe in some special architecture what he/she said is right, but in the x86 family at least I know they are the same. Because for doing this the CPU will do a substraction (a - b) and then check the flags of the flag register. Two bits of that register are called ZF (zero Flag) and SF (sign flag), and it is done in one cycle, because it will do it with one mask operation.

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