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 
main(int argc,char * argv[])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 }
45