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      1 #include "timing.h"
      2 #include <stdio.h>
      3 
      4 #define INPUT_TYPE int64_t
      5 #define INPUT_SIZE 256
      6 #define FUNCTION_NAME __muldi3
      7 
      8 #ifndef LIBNAME
      9 #define LIBNAME UNKNOWN
     10 #endif
     11 
     12 #define LIBSTRING		LIBSTRINGX(LIBNAME)
     13 #define LIBSTRINGX(a)	LIBSTRINGXX(a)
     14 #define LIBSTRINGXX(a)	#a
     15 
     16 INPUT_TYPE FUNCTION_NAME(INPUT_TYPE input1, INPUT_TYPE input2);
     17 
     18 int main(int argc, char *argv[]) {
     19 	INPUT_TYPE input1[INPUT_SIZE];
     20 	INPUT_TYPE input2[INPUT_SIZE];
     21 	int i, j;
     22 
     23 	srand(42);
     24 
     25 	// Initialize the input array with data of various sizes.
     26 	for (i=0; i<INPUT_SIZE; ++i) {
     27 		input1[i] = (((int64_t)rand() << 36) | (uint64_t)rand()) >> (rand() & 63);
     28 		input2[i] = (((int64_t)rand() << 36) | (uint64_t)rand()) >> (rand() & 63);
     29 	}
     30 
     31 	int64_t fixedInput = INT64_C(0x1234567890ABCDEF);
     32 
     33 	double bestTime = __builtin_inf();
     34 	void *dummyp;
     35 	for (j=0; j<1024; ++j) {
     36 
     37 		uint64_t startTime = mach_absolute_time();
     38 		for (i=0; i<INPUT_SIZE; ++i)
     39 			FUNCTION_NAME(input1[i], input2[i]);
     40 		uint64_t endTime = mach_absolute_time();
     41 
     42 		double thisTime = intervalInCycles(startTime, endTime);
     43 		bestTime = __builtin_fmin(thisTime, bestTime);
     44 
     45 		// Move the stack alignment between trials to eliminate (mostly) aliasing effects
     46 		dummyp = alloca(1);
     47 	}
     48 
     49 	printf("%16s: %f cycles.\n", LIBSTRING, bestTime / (double) INPUT_SIZE);
     50 
     51 	return 0;
     52 }
     53