[FFmpeg-devel] [RFC] [PATCH] CPU caps detection in FFmpeg

[Diego Biurrun]

On Sun, Mar 22, 2009 at 09:52:17AM +0100, Stefano Sabatini wrote:
> On date Sunday 2009-03-22 02:16:56 +0100, Michael Niedermayer encoded:
> > On Sun, Mar 22, 2009 at 02:00:12AM +0100, Stefano Sabatini wrote:
> > > 
> > > I took Michael request for having in vf_scale.c all the features of
> > > the libmpcodecs one very seriously ;-), so here it is an experimental
> > > attempt for implementing the sws CPU flags detection, so I ported the
> > > code from Mess^H^H^HPlayer.
> > > 
> > > It is not meant for review, but just to see if it could be eventually
> > > accepted, and if this is the right approach.
> > > 
> > > Just in the case, should I allocate av_cpu_caps statically?
> > 
> > what problem does
> > libavcodec/x86/cpuid.c
> > have?
> 
> 1) first of all I didn't know of its existence ;-)
> 
> 2) it fails at compilation with:
> 
> cd ~/src/libavfilter-soc/ffmpeg/libavcodec; make x86/cpuid-test; and
> x86/cpuid-test gcc -DHAVE_AV_CONFIG_H
> -I.. -I"/home/stefano/src/libavfilter-soc/ffmpeg"
> -I/home/stefano/include -D_ISOC99_SOURCE -D_POSIX_C_SOURCE=200112
> -std=c99 -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -g3
> -Wdeclaration-after-statement -Wall -Wno-switch
> -Wdisabled-optimization -Wpointer-arith -Wredundant-decls
> -Wno-pointer-sign -Wcast-qual -Wwrite-strings -Wtype-limits -Wundef
> -fno-math-errno -fno-signed-zeros -DTEST -c -o x86/cpuid-test.o
> x86/cpuid.c
> cc1: warning: -funit-at-a-time is required for inlining of functions that are only called once
> x86/cpuid.c:42:20: error: macro "mm_support" passed 1 arguments, but takes just 0
> x86/cpuid.c:43: error: expected ?=?, ?,?, ?;?, ?asm? or ?__attribute__? before ?{? token
> x86/cpuid.c: In function ?main?:
> x86/cpuid.c:127: error: expected identifier or ?(? before numeric constant
> x86/cpuid.c:128: error: lvalue required as left operand of assignment
> make: *** [x86/cpuid-test.o] Error 1
> 
> This is due to the fact that the mm_support() and mm_flags are defined
> as macro by dsputil.h.

No, the problem is that you have a broken tree or whatever.  Just

make libavcodec/x86/cpuid-test

works absolutely fine here.

Diego