[Ffmpeg-devel] [PATCH] SSE counterpart of ff_imdct_calc_3dn2

[Michael Niedermayer]

Hi

On Tue, Sep 19, 2006 at 01:25:14PM +0200, Guillaume POIRIER wrote:
> Hi,
> 
> On 9/19/06, Zuxy Meng <zuxy.meng at gmail.com> wrote:
> >2006/9/19, Guillaume Poirier <gpoirier at mplayerhq.hu>:
> >> Diego Biurrun wrote:
> >> > On Thu, Sep 14, 2006 at 11:02:48AM +0200, Guillaume POIRIER wrote:
> >> >>On 9/14/06, Zuxy Meng <zuxy.meng at gmail.com> wrote:
> >> >>>2006/9/13, Benjamin Larsson <banan at student.ltu.se>:
> 
> >> >>Well, it still needs -fomit-frame-pointer to get compiled at all, so I
> >> >>don't think it's good to go, unless we add the requirement that FFmpeg
> >> >>needs to be compiled with -fomit-frame-pointer.
> >> >
> >> >
> >> > Wasn't this just on your specific gcc version?
> >>
> >> No, I've checked with GCC 3.3, 4.0.3, 4.2.x (from svn) and they all
> >> fail on the same code on IA32.
> >
> >IIRC another thread has pointed out that even ff_imdct_3dn2.c itself
> >won't compile without -fomit-frame-pointer....
> 
> That's possible, but I can't test. I don't have a 32-bits machine with
> 3dnow2 support in it...

you dont need one for _compiling_


> 
> Michael, what's your opinion about it?
> 
> Should lavc's makefile append '-fomit-frame-pointer' to compile
> libavcodec/i386/fft_3dn2.c as well as ff_imdct_calc_sse.diff?
> 
> It's a bit of a hack, but it would work.

hmm, dunno, what about PIC?

if noPIC works and PIC needs -fomit-frame-pointer then ive no objections
but if noPIC needs -fomit-frame-pointer then PIC as it has 1 register less
shouldnt work even with -fomit-frame-pointer and thats IMHO not so ideal

[...]
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Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

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