[FFmpeg-devel] [PATCH] set HAVE_MMX2 in config.h

Zuxy Meng zuxy.meng
Wed Mar 19 06:39:16 CET 2008


2008/3/19, Alexander Strange <astrange at ithinksw.com>:
> On Tue, Mar 18, 2008 at 11:03 PM, Michael Niedermayer <michaelni at gmx.at> wrote:
> >
> > On Tue, Mar 18, 2008 at 10:37:34PM -0400, Alexander Strange wrote:
> >  >
> >  > On Mar 18, 2008, at 5:57 PM, Gert Vervoort wrote:
> >  >>
> >  >> Enabling HAVE_MMX2 for swscale gives an linker error on x86-64 when
> >  >> compiling as a shared library:
> >  >>
> >  >> gcc -shared -Wl,-soname,libswscale.so.0 -L"/tmp/ffmpeg"/libavutil
> >  >> -rdynamic -export-dynamic -Wl,--warn-common -Wl,--as-needed
> >  >> -Wl,-rpath-link,"/tmp/ffmpeg"/libavcodec
> >  >> -Wl,-rpath-link,"/tmp/ffmpeg"/libavformat
> >  >> -Wl,-rpath-link,"/tmp/ffmpeg"/libavutil -Wl,-Bsymbolic -o
> >  >> libswscale.so.0 rgb2rgb.o swscale.o yuv2rgb.o -lavutil -lz -pthread -lm
> >  >> -lamrnb -lm -lamrwb -lm -lfaac -lfaad -lmp3lame -lm   -ldl -ldl -lX11
> >  >> -lXext
> >  >> /usr/bin/ld: swscale.o: relocation R_X86_64_32S against `a local symbol'
> >  >> can not be used when making a shared object; recompile with -fPIC
> >  >> swscale.o: could not read symbols: Bad value
> >  >> collect2: ld returned 1 exit status
> >  >> make[1]: *** [libswscale.so.0] Error 1
> >  >> make[1]: Leaving directory `/tmp/ffmpeg/libswscale'
> >  >> make: *** [lib] Error 2
> >  >> [gert at apollo ffmpeg]$
> >  >
> >  > The attached patch fixes 64-bit but breaks any system with an
> >  > EXTERN_PREFIX.
> >  > Suggestions?
> >
> >  Well figure out the proper syntax for all the systems and do whatever
> >  is needed so that it ends in there.
> >
> >  [...]
>
> This patch generates the right asm by making a new LOCAL_MANGLE().
>
> I tested it on 64-bit, but it turns out fast_bilinear crashes there
> whether or not the patch is applied, unless you run it under valgrind.
> Don't have time to debug it.

Because we're using self-modifying code but don't follow Intel/AMD's
suggestions?
-- 
Zuxy
Beauty is truth,
While truth is beauty.
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