trying to simplify an algorithm

Ian Molton spyro at f2s.com
Mon Feb 28 03:42:15 PST 2005


Johan V. wrote:

> I know it's very obscured. Think about the wasted clock cycles for a minute,
> the above can be implemented without conditional jumps ...

More to the point though I think technically its broken. Im fairly sure 
C only defines 0 to be false. *all* other values are true, therefore you 
are relying on the compiler to use 1.

also from an assembler standpoint, some CPUs may not be able to 
implement reg = (a>0) without a branch.

best to use conditionals and let the compiler work out how best to fit 
them around the target CPU. (even better to go fix gcc so it does that well)



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