Are bit operations quick?

Posted by flashnik on Stack Overflow See other posts from Stack Overflow or by flashnik
Published on 2010-05-10T22:10:06Z Indexed on 2010/05/10 22:14 UTC
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bit-manipulation

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c++

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Performance

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storage

I'm dealing with a problem which needs to work with a lot of data. Currently its' values are represented as unsigned int. I know that real values do not exceed some limit, say 1000. That means that I can use unsigned short to store it. One profit is that it'll use less space. Do I have to pay for it by loosing in performance?

Another assumption. I decided to store data as short but all calling functions use int, so I need to convert between these datatypes when storing/extracting values. Wiil the performance lost be dramatic?

Third assumption. Due to great wish to econom memory I decided to use not short but just 10 bits packed into array of unsigned int. What will happen in this case comparing with previous ones?

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