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A comment on What is your favourite C programming trick?. Parent comment

Re:What is your favourite C programming trick? by matthavener on Friday October 14, 2011 @10:29AM (#3111276)
The ring buffer is a nice trick, but it only works on array sizes that are a multiple of 2. The generalized version would be "array[i++ % ARRAY_SIZE] = data". If ARRAY_SIZE happens to be a multiple of two, I'm sure most compilers would optimize to a bitmask anyways..
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Re:What is your favourite C programming trick? by mansr on Friday October 14, 2011 @10:42AM (#3111338)
And if it is not a power of 2, the % operation will be anything but fast. If a size not a power of 2 is strictly required, a simple increment and compare is almost certainly faster.
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