[MPlayer-dev-eng] [RFC] disable fastmemcpy on x86-64 by default

[Sven Gothel]

On Sunday 27 May 2007 at 10:19, Reimar D?ffinger wrote:
> Hello,
> since SSE is part of the x86-64 architecture, at least glibc makes use
> of it for its memcpy and some quick (and imprecise) tests indicate that
> it's at least not slower.
> So what do you think about attached patch? Can someone do more concise
> benchmarks?
> 

Well, as Michael N. stated, it depends on size,
that's why the next gcc will decide on that size, 
how the memcpy 'function call' will be treated.
I.e. all below a 1 kbytes can be copied faster with sse2.

http://www.greyhound-data.com/gunnar/glibc/index.htm?page=benchmarks

So, till this new gcc is available, IMHO a generic memcpy inline function
shall make one happy, if size<1024 { .. double pointer stream copy } else
old fashion glibc memcpy ..

And yes .. it makes a huge difference ;-)

Cheers, Sven

> Greetings,
> Reimar Döffinger
> 



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