On Fri, Nov 01, 2013 at 04:18:50PM -0000, David Laight wrote: > > How would you suggest replacing the jumps in this case? I agree it would be > > faster here, but I'm not sure how I would implement an increment using a > > single > > conditional move. > > I think you need 3 instructions, move a 0, conditionally move a 1 > then add. I suspect it won't be a win! > > If you do 'win' it is probably very dependent on how the instructions > get scheduled onto the execution units - which will probably make > it very cpu type dependant. > > David > I agree, that sounds interesting, but very cpu dependent. Thanks for the suggestion, Ben, but I think it would be better if we just did the prefetch here and re-addressed this area when AVX (or addcx/addox) instructions were available for testing on hardware.
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