PeerStreamer

/*

 * CPU detection code, extracted from mmx.h

 * (c)1997-99 by H. Dietz and R. Fisher

 * Converted to C and improved by Fabrice Bellard.

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#include <stdlib.h>

#include "dsputil.h"

#undef printf

#ifdef ARCH_X86_64

#  define REG_b "rbx"

#  define REG_S "rsi"

#else

#  define REG_b "ebx"

#  define REG_S "esi"

#endif

/* ebx saving is necessary for PIC. gcc seems unable to see it alone */

#define cpuid(index,eax,ebx,ecx,edx)\

    __asm __volatile\

        ("mov %%"REG_b", %%"REG_S"\n\t"\

         "cpuid\n\t"\

         "xchg %%"REG_b", %%"REG_S\

         : "=a" (eax), "=S" (ebx),\

           "=c" (ecx), "=d" (edx)\

         : "0" (index));

/* Function to test if multimedia instructions are supported...  */

int mm_support(void)

{

    int rval = 0;

    int eax, ebx, ecx, edx;

    int max_std_level, max_ext_level, std_caps=0, ext_caps=0;

    long a, c;

    __asm__ __volatile__ (

                          /* See if CPUID instruction is supported ... */

                          /* ... Get copies of EFLAGS into eax and ecx */

                          "pushf\n\t"

                          "pop %0\n\t"

                          "mov %0, %1\n\t"

                          /* ... Toggle the ID bit in one copy and store */

                          /*     to the EFLAGS reg */

                          "xor $0x200000, %0\n\t"

                          "push %0\n\t"

                          "popf\n\t"

                          /* ... Get the (hopefully modified) EFLAGS */

                          "pushf\n\t"

                          "pop %0\n\t"

                          : "=a" (a), "=c" (c)

                          :

                          : "cc"

                          );

    if (a == c)

        return 0; /* CPUID not supported */

    cpuid(0, max_std_level, ebx, ecx, edx);

    if(max_std_level >= 1){

        cpuid(1, eax, ebx, ecx, std_caps);

        if (std_caps & (1<<23))

            rval |= MM_MMX;

        if (std_caps & (1<<25))

            rval |= MM_MMXEXT | MM_SSE;

        if (std_caps & (1<<26))

            rval |= MM_SSE2;

        if (ecx & 1)

            rval |= MM_SSE3;

        if (ecx & 0x00000200 )

            rval |= MM_SSSE3;

    }

    cpuid(0x80000000, max_ext_level, ebx, ecx, edx);

    if(max_ext_level >= 0x80000001){

        cpuid(0x80000001, eax, ebx, ecx, ext_caps);

        if (ext_caps & (1<<31))

            rval |= MM_3DNOW;

        if (ext_caps & (1<<30))

            rval |= MM_3DNOWEXT;

        if (ext_caps & (1<<23))

            rval |= MM_MMX;

        if (ext_caps & (1<<22))

            rval |= MM_MMXEXT;

    }

#if 0

    av_log(NULL, AV_LOG_DEBUG, "%s%s%s%s%s%s%s%s\n",

        (rval&MM_MMX) ? "MMX ":"",

        (rval&MM_MMXEXT) ? "MMX2 ":"",

        (rval&MM_SSE) ? "SSE ":"",

        (rval&MM_SSE2) ? "SSE2 ":"",

        (rval&MM_SSE3) ? "SSE3 ":"",

        (rval&MM_SSSE3) ? "SSSE3 ":"",

        (rval&MM_3DNOW) ? "3DNow ":"",

        (rval&MM_3DNOWEXT) ? "3DNowExt ":"");

#endif

    return rval;

}

#ifdef __TEST__

int main ( void )

{

  int mm_flags;

  mm_flags = mm_support();

  printf("mm_support = 0x%08X\n",mm_flags);

  return 0;

}

#endif