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