compiler-rt/test/builtins/timing/floatundidf.c

   1 #include "timing.h"
   2 #include <stdio.h>
   3
   4 #ifndef LIBNAME
   5 #define LIBNAME UNKNOWN
   6 #endif
   7
   8 #define LIBSTRING               LIBSTRINGX(LIBNAME)
   9 #define LIBSTRINGX(a)   LIBSTRINGXX(a)
  10 #define LIBSTRINGXX(a)  #a
  11
  12 double __floatundidf(uint64_t x);
  13
  14 int main(int argc, char *argv[]) {
  15 #define INPUT_SIZE 512
  16         uint64_t input[INPUT_SIZE];
  17         int i, j;
  18
  19         srand(42);
  20
  21         // Initialize the input array with data of various sizes.
  22         for (i=0; i<INPUT_SIZE; ++i)
  23                 input[i] = (((uint64_t)rand() << 32) | (uint64_t)rand()) >> (rand() & 63);
  24
  25         double bestTime = __builtin_inf();
  26         void *dummyp;
  27         for (j=0; j<1024; ++j) {
  28
  29                 uint64_t startTime = mach_absolute_time();
  30                 for (i=0; i<INPUT_SIZE; ++i)
  31                         __floatundidf(input[i]);
  32                 uint64_t endTime = mach_absolute_time();
  33
  34                 double thisTime = intervalInCycles(startTime, endTime);
  35                 bestTime = __builtin_fmin(thisTime, bestTime);
  36
  37                 // Move the stack alignment between trials to eliminate (mostly) aliasing effects
  38                 dummyp = alloca(1);
  39         }
  40
  41         printf("%16s: %f cycles.\n", LIBSTRING, bestTime / (double) INPUT_SIZE);
  42
  43         return 0;
  44 }