c - What is the replacement of mod operator? -


this question has answer here:

i have code segment requires remainder of 2 ints. using modulus operator usual hearing takes more time. asking there way remainder more efficiently mod operation... following code 

int rem=gid%bpp

gid being int , bpp being 2,4,8,16,32.

it appears question bpp power of 2, in case can use instead:

int rem = gid & (bpp - 1);

however should not optimise prematurely - unless have profiled , know mod operation bottleneck should leave in original, more readable form.


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