How does help me use popcnt to find how many bit pairs are used and how many are... | Hacker News

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		adgar on Sept 5, 2011 \| parent \| context \| favorite \| on: X86 Oddities How does help me use popcnt to find how many bit pairs are used and how many are empty? Edit: whoops, I gotcha. I'll profile this. Edit 2: no I won't profile it, because I don't have the instruction. Damn.

acqq on Sept 5, 2011 [–]

You don't need to have POPCNT to implement much faster bit counting:

http://graphics.stanford.edu/~seander/bithacks.html#CountBit...

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