[FFmpeg-devel] [PATCH] avfilter, swresample, swscale: use fabs, fabsf instead of FFABS

Carl Eugen Hoyos cehoyos at ag.or.at
Wed Oct 14 12:49:45 CEST 2015

Ganesh Ajjanagadde <gajjanag <at> mit.edu> writes:

> What? My numbers actually show that the new code may be faster -

No, you are misunderstanding the numbers you posted.
(Or I misunderstand them but nobody said so yet.)

Highest runs are most relevant, skips have to be 
avoided (afaik).


> If you continue to post such stuff that has no basis, I might actually
> get tempted into finding out for which floating point values the new
> code is significantly faster, craft a relevant audio file, and post it
> showing a huge performance difference - my random numbers benchmark
> shows there must exist such values.

Please do so!

> > The more important question is if you can see the same
> > changes in the disassembly of af_astats.o as what
> > ubitux posted here for a short test function?
> I do. He uses clang/gcc, so do I.

Sorry, my understanding fails here (I am not a native speaker):
You did look at the disassembly of af_astats.o and there is 
inlined code instead of a function call?

> The reason (irrelevant) is that both
> of us run Arch.
> What is "more relevant" is if _you_ can see the changes 
> on some non Linux platform.

If you could show that it is faster on any platform 
I would already be happy!

Carl Eugen

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