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performance - Speed of Comparison operators

In languages such as... well anything, both operators for < and <= (and their opposites) exist. Which would be faster, and how are they interpreted?

if (x <= y) { blah; }

or

if (x < y + 1) { blah; }

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Assuming no compiler optimizations (big assumption), the first will be faster, as <= is implemented by a single jle instruction, where as the latter requires an addition followed by a jl instruction.

http://en.wikibooks.org/wiki/X86_Assembly/Control_Flow#Jump_if_Less


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