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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 extern uint32_t perf_start_count, perf_interval_count;
  28
  29 #ifdef __WATCOMC__
  30 void perf_start(void);
  31 #pragma aux perf_start = \
  32         "xor eax, eax" \
  33         "cpuid" \
  34         "rdtsc" \
  35         "mov [perf_start_count], eax" \
  36         modify[eax ebx ecx edx];
  37
  38 void perf_end(void);
  39 #pragma aux perf_end = \
  40         "xor eax, eax" \
  41         "cpuid" \
  42         "rdtsc" \
  43         "sub eax, [perf_start_count]" \
  44         "mov [perf_interval_count], eax" \
  45         modify [eax ebx ecx edx];
  46 #endif
  47
  48 #ifdef __GNUC__
  49 #define perf_start()  asm volatile ( \
  50         "xor %%eax, %%eax\n" \
  51         "cpuid\n" \
  52         "rdtsc\n" \
  53         "mov %%eax, %0\n" \
  54         : "=m"(perf_start_count) \
  55         :: "%eax", "%ebx", "%ecx", "%edx")
  56
  57 #define perf_end() asm volatile ( \
  58         "xor %%eax, %%eax\n" \
  59         "cpuid\n" \
  60         "rdtsc\n" \
  61         "sub %1, %%eax\n" \
  62         "mov %%eax, %0\n" \
  63         : "=m"(perf_interval_count) \
  64         : "m"(perf_start_count) \
  65         : "%eax", "%ebx", "%ecx", "%edx")
  66 #endif
  67
  68 #ifdef _MSC_VER
  69 #define perf_start() \
  70         do { \
  71                 __asm { \
  72                         xor eax, eax \
  73                         cpuid \
  74                         rdtsc \
  75                         mov [perf_start_count], eax \
  76                 } \
  77         } while(0)
  78
  79 #define perf_end() \
  80         do { \
  81                 __asm { \
  82                         xor eax, eax \
  83                         cpuid \
  84                         rdtsc \
  85                         sub eax, [perf_start_count] \
  86                         mov [perf_interval_count], eax \
  87                 } \
  88         } while(0)
  89 #endif
  90
  91 #endif  /* UTIL_H_ */