quicktime/ffmpeg/libavcodec/i386/cputest.c

   1 /* Cpu detection code, extracted from mmx.h ((c)1997-99 by H. Dietz
   2    and R. Fisher). Converted to C and improved by Fabrice Bellard */
   3
   4 #include <stdlib.h>
   5 #include "../dsputil.h"
   6
   7 #ifdef ARCH_X86_64
   8 #  define REG_b "rbx"
   9 #  define REG_S "rsi"
  10 #else
  11 #  define REG_b "ebx"
  12 #  define REG_S "esi"
  13 #endif
  14
  15 /* ebx saving is necessary for PIC. gcc seems unable to see it alone */
  16 #define cpuid(index,eax,ebx,ecx,edx)\
  17     __asm __volatile\
  18         ("mov %%"REG_b", %%"REG_S"\n\t"\
  19          "cpuid\n\t"\
  20          "xchg %%"REG_b", %%"REG_S\
  21          : "=a" (eax), "=S" (ebx),\
  22            "=c" (ecx), "=d" (edx)\
  23          : "0" (index));
  24
  25 /* Function to test if multimedia instructions are supported...  */
  26 int mm_support(void)
  27 {
  28     int rval = 0;
  29     int eax, ebx, ecx, edx;
  30     int max_std_level, max_ext_level, std_caps=0, ext_caps=0;
  31     long a, c;
  32
  33     __asm__ __volatile__ (
  34                           /* See if CPUID instruction is supported ... */
  35                           /* ... Get copies of EFLAGS into eax and ecx */
  36                           "pushf\n\t"
  37                           "pop %0\n\t"
  38                           "mov %0, %1\n\t"
  39
  40                           /* ... Toggle the ID bit in one copy and store */
  41                           /*     to the EFLAGS reg */
  42                           "xor $0x200000, %0\n\t"
  43                           "push %0\n\t"
  44                           "popf\n\t"
  45
  46                           /* ... Get the (hopefully modified) EFLAGS */
  47                           "pushf\n\t"
  48                           "pop %0\n\t"
  49                           : "=a" (a), "=c" (c)
  50                           :
  51                           : "cc"
  52                           );
  53
  54     if (a == c)
  55         return 0; /* CPUID not supported */
  56
  57     cpuid(0, max_std_level, ebx, ecx, edx);
  58
  59     if(max_std_level >= 1){
  60         cpuid(1, eax, ebx, ecx, std_caps);
  61         if (std_caps & (1<<23))
  62             rval |= MM_MMX;
  63         if (std_caps & (1<<25))
  64             rval |= MM_MMXEXT | MM_SSE;
  65         if (std_caps & (1<<26))
  66             rval |= MM_SSE2;
  67     }
  68
  69     cpuid(0x80000000, max_ext_level, ebx, ecx, edx);
  70
  71     if(max_ext_level >= 0x80000001){
  72         cpuid(0x80000001, eax, ebx, ecx, ext_caps);
  73         if (ext_caps & (1<<31))
  74             rval |= MM_3DNOW;
  75         if (ext_caps & (1<<30))
  76             rval |= MM_3DNOWEXT;
  77         if (ext_caps & (1<<23))
  78             rval |= MM_MMX;
  79     }
  80
  81     cpuid(0, eax, ebx, ecx, edx);
  82     if (       ebx == 0x68747541 &&
  83                edx == 0x69746e65 &&
  84                ecx == 0x444d4163) {
  85         /* AMD */
  86         if(ext_caps & (1<<22))
  87             rval |= MM_MMXEXT;
  88     } else if (ebx == 0x746e6543 &&
  89                edx == 0x48727561 &&
  90                ecx == 0x736c7561) {  /*  "CentaurHauls" */
  91         /* VIA C3 */
  92         if(ext_caps & (1<<24))
  93           rval |= MM_MMXEXT;
  94     } else if (ebx == 0x69727943 &&
  95                edx == 0x736e4978 &&
  96                ecx == 0x64616574) {
  97         /* Cyrix Section */
  98         /* See if extended CPUID level 80000001 is supported */
  99         /* The value of CPUID/80000001 for the 6x86MX is undefined
 100            according to the Cyrix CPU Detection Guide (Preliminary
 101            Rev. 1.01 table 1), so we'll check the value of eax for
 102            CPUID/0 to see if standard CPUID level 2 is supported.
 103            According to the table, the only CPU which supports level
 104            2 is also the only one which supports extended CPUID levels.
 105         */
 106         if (eax < 2)
 107             return rval;
 108         if (ext_caps & (1<<24))
 109             rval |= MM_MMXEXT;
 110     }
 111 #if 0
 112     av_log(NULL, AV_LOG_DEBUG, "%s%s%s%s%s%s\n",
 113         (rval&MM_MMX) ? "MMX ":"",
 114         (rval&MM_MMXEXT) ? "MMX2 ":"",
 115         (rval&MM_SSE) ? "SSE ":"",
 116         (rval&MM_SSE2) ? "SSE2 ":"",
 117         (rval&MM_3DNOW) ? "3DNow ":"",
 118         (rval&MM_3DNOWEXT) ? "3DNowExt ":"");
 119 #endif
 120     return rval;
 121 }
 122
 123 #ifdef __TEST__
 124 int main ( void )
 125 {
 126   int mm_flags;
 127   mm_flags = mm_support();
 128   printf("mm_support = 0x%08X\n",mm_flags);
 129   return 0;
 130 }
 131 #endif