ffmpeg/libavutil/x86/emms.h

   1 /*
   2  * This file is part of FFmpeg.
   3  *
   4  * FFmpeg is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * FFmpeg is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with FFmpeg; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #ifndef AVUTIL_X86_EMMS_H
  20 #define AVUTIL_X86_EMMS_H
  21
  22 #include "config.h"
  23 #include "libavutil/attributes.h"
  24 #include "libavutil/cpu.h"
  25
  26 void avpriv_emms_yasm(void);
  27
  28 #if HAVE_MMX_INLINE
  29 #   define emms_c emms_c
  30 /**
  31  * Empty mmx state.
  32  * this must be called between any dsp function and float/double code.
  33  * for example sin(); dsp->idct_put(); emms_c(); cos()
  34  */
  35 static av_always_inline void emms_c(void)
  36 {
  37     if(av_get_cpu_flags() & AV_CPU_FLAG_MMX)
  38         __asm__ volatile ("emms" ::: "memory");
  39 }
  40 #elif HAVE_MMX && HAVE_MM_EMPTY
  41 #   include <mmintrin.h>
  42 #   define emms_c _mm_empty
  43 #elif HAVE_MMX_EXTERNAL
  44 #   define emms_c avpriv_emms_yasm
  45 #endif /* HAVE_MMX_INLINE */
  46
  47 #endif /* AVUTIL_X86_EMMS_H */