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 } 45
