[FFmpeg-devel] [RFC] remove table_4_3_value with CONFIG_SMALL

Reimar Döffinger Reimar.Doeffinger
Thu Oct 15 12:28:09 CEST 2009


On Thu, Oct 15, 2009 at 11:19:05AM +0100, M?ns Rullg?rd wrote:
> Reimar D?ffinger <Reimar.Doeffinger at gmx.de> writes:
> > On Thu, Oct 15, 2009 at 09:59:33AM +0100, M?ns Rullg?rd wrote:
> >> It will totally murder performance on anything without an FPU.  Those
> >> are also the systems most likely to need CONFIG_SMALL, so this is not
> >> acceptable.
> >
> > Actually the only system that currently _needs_ CONFIG_SMALL is IA64.
> 
> IA64 builds with a plain ./configure over here.  It's --enable-shared
> that's breaking it.

Well, then IA64 with --enable-shared is the only system that definitely
needs it (though I hope that if I move the ff_sin tables to .rodata as well
hardcoded-tables will fix it).

> > Also, this is nearly the largest table in all of FFmpeg, so I very much
> > think it should be under CONFIG_SMALL.
> 
> I repeat, there is a large overlap between systems with limited RAM
> and those without FPU.  We don't want to make CONFIG_SMALL useless on
> those.  Didn't you have a different idea without floating-point too?

No, I only had a suggestion that avoids exp2f, it still needs cbrtf and
float multiplication.
It probably should be investigated more, the current form of the patch
probably is nonsense. I still don't think that it's a sensible approach
to have CONFIG_SMALL assume a slow/inexistent FPU.



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