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   1 #ifndef UTIL_H_
   2 #define UTIL_H_
   3
   4 #include "inttypes.h"
   5
   6 #ifdef __GNUC__
   7 #define INLINE __inline
   8
   9 #elif defined(__WATCOMC__)
  10 #define INLINE __inline
  11
  12 #else
  13 #define INLINE
  14 #endif
  15
  16 /* fast conversion of double -> 32bit int
  17  * for details see:
  18  *  - http://chrishecker.com/images/f/fb/Gdmfp.pdf
  19  *  - http://stereopsis.com/FPU.html#convert
  20  */
  21 static INLINE int32_t cround64(double val)
  22 {
  23         val += 6755399441055744.0;
  24         return *(int32_t*)&val;
  25 }
  26
  27 uint32_t perf_start_count, perf_interval_count;
  28
  29 #ifdef __WATCOMC__
  30 void perf_start(void);
  31 #pragma aux perf_start = \
  32         "rdtsc" \
  33         "mov [perf_start_count], eax" \
  34         modify[eax edx];
  35
  36 void perf_end(void);
  37 #pragma aux perf_end = \
  38         "rdtsc" \
  39         "sub eax, [perf_start_count]" \
  40         "mov [perf_interval_count], eax" \
  41         modify [eax edx];
  42 #endif
  43
  44 #ifdef __GNUC__
  45 #define perf_start()  asm volatile ( \
  46         "rdtsc\n" \
  47         "mov %%eax, %0\n" \
  48         : "=m"(perf_start_count) :: "%eax", "%edx")
  49
  50 #define perf_end() asm volatile ( \
  51         "rdtsc\n" \
  52         "sub %1, %%eax\n" \
  53         "mov %%eax, %0\n" \
  54         : "=m"(perf_interval_count) \
  55         : "m"(perf_start_count) \
  56         : "%eax", "%edx")
  57 #endif
  58
  59 #ifdef _MSC_VER
  60 #define perf_start() \
  61         do { \
  62                 __asm { \
  63                         rdtsc \
  64                         mov [perf_start_count], eax \
  65                 } \
  66         } while(0)
  67
  68 #define perf_end() \
  69         do { \
  70                 __asm { \
  71                         rdtsc \
  72                         sub eax, [perf_start_count] \
  73                         mov [perf_interval_count], eax \
  74                 } \
  75         } while(0)
  76 #endif
  77
  78 #endif  /* UTIL_H_ */