ffmpeg/libavcodec/x86/cpuid.c

135 lines
3.6 KiB
C

/*
* 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 "libavutil/x86_cpu.h"
#include "libavcodec/dsputil.h"
#undef printf
/* 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;
x86_reg a, c;
#if ARCH_X86_64
#define PUSHF "pushfq\n\t"
#define POPF "popfq\n\t"
#else
#define PUSHF "pushfl\n\t"
#define POPF "popfl\n\t"
#endif
__asm__ volatile (
/* See if CPUID instruction is supported ... */
/* ... Get copies of EFLAGS into eax and ecx */
PUSHF
"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
/* ... Get the (hopefully modified) EFLAGS */
PUSHF
"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 |= FF_MM_MMX;
if (std_caps & (1<<25))
rval |= FF_MM_MMXEXT
#if HAVE_SSE
| FF_MM_SSE;
if (std_caps & (1<<26))
rval |= FF_MM_SSE2;
if (ecx & 1)
rval |= FF_MM_SSE3;
if (ecx & 0x00000200 )
rval |= FF_MM_SSSE3
#endif
;
}
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 |= FF_MM_3DNOW;
if (ext_caps & (1<<30))
rval |= FF_MM_3DNOWEXT;
if (ext_caps & (1<<23))
rval |= FF_MM_MMX;
if (ext_caps & (1<<22))
rval |= FF_MM_MMXEXT;
}
#if 0
av_log(NULL, AV_LOG_DEBUG, "%s%s%s%s%s%s%s%s\n",
(rval&FF_MM_MMX) ? "MMX ":"",
(rval&FF_MM_MMXEXT) ? "MMX2 ":"",
(rval&FF_MM_SSE) ? "SSE ":"",
(rval&FF_MM_SSE2) ? "SSE2 ":"",
(rval&FF_MM_SSE3) ? "SSE3 ":"",
(rval&FF_MM_SSSE3) ? "SSSE3 ":"",
(rval&FF_MM_3DNOW) ? "3DNow ":"",
(rval&FF_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