c - condition vs division -

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c - condition vs division -

given next statement executed lot:

inormval = ival / uratio;

would next create more sense (performance wise) if uratio == 1 (90%) of time?

if(uratio > 1) inormval = ival / uratio; else inormval = ival;

thanks..

you need profile measurement, it's hard guess. compiler might decide you're wrong , remove test, check , without optimizing.

the actual cost of (integer) partition might rather low, on modern desktop-class processors. according this pdf, costs on modern (wolfdale/nehalem/sandy bridge) of 32/32-bit partition 14-23/17-28/20-28 cycles respectively. so, if lot, might add together up. in case, parallel (vectorized) options if possible.

i seek avoid if @ possible, since introduces branch. branches have 2 disadvantages: create code more complex introducing multiple paths programmer reading code has understand, , can introduce execution overhead.

c performance division

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