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> > uninlining the code is too high a cost.
>
> I question that. Athlon does branch prediction on call targets, function
> calls are cheap. 3dnow saves 25%-50% of cycles on a copy. How many function
> calls can be paid for with 1000 cycles or so?
>
> My patch still inlines the standard string const_memcpy for the case of
> small known length.

We have a very large number of memcpy's of unknown short length (often in
interrupts) that are close to branches. A lot of

if(foo==NULL)
return
memcpy(..
stuff for example.

Im more than happy for someone to do the benches and prove me wrong

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