That depends on the CPU used. Modern CPU have more arithmetic units than logical... | Hacker News

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		feb on July 26, 2011 \| parent \| context \| favorite \| on: Ten Ways to Check if an Integer Is a Power Of Two ... That depends on the CPU used. Modern CPU have more arithmetic units than logical units and can perform more divisions than bit shifts. There was a good video presentation of that, but I can't find the link now. EDIT: http://blogs.msdn.com/b/shawnhar/archive/2007/03/19/a-story-... gives other reasons why multiplications can be faster than bit shifts.

aidenn0 on July 26, 2011 [–]

That's multiplies, not divides. Modern CPUs are still faster at shifts than divides, even the pentium4, which lacked a single-cycle shift unit.

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