/*	Micro-Benchmark - benchmark using RDTSC

	Compare writing doubles to an array vs the sin() of that value

*/

#include <stdio.h>
#include <math.h>

/*	select mode	*/
#define WRITE_DOUBLE
#undef	COMPUTE_SIN

/*	My machine runs at 3.2 GHz	*/
#define PROCESSOR_FREQ	3200E6
#include "rdtsc.h"

/*	how many repetitions to measure	*/
#define REPS			1000

/*	size of the array	*/
#define ARRAY_SIZE		100

/*	Set MODE variables	*/
#if defined WRITE_DOUBLE
#define MODE "write double"
#elif defined COMPUTE_SIN
#define MODE "compute sin()"
#else
#error MODE undefined
#endif

/*	sadly not defined in VisualStudio.NET 2003	*/
#ifndef MIN
#define MIN(a,b) ((a) < (b) ? (a) : (b))
#endif



void main(void)
{
	double src[ARRAY_SIZE], dst[ARRAY_SIZE];
	tsc_counter t0, t1, t_min;
	int i, j;

	/*	init	*/
	for (i=0; i<ARRAY_SIZE; i++)
		src[i] = (double) i;

	/*	warm up everything; I ignore the Intel documentation on CPUID	*/

	/*	check it...	*/
	rdtsc_works();

	RDTSC(t0);
	for (i=0; i<ARRAY_SIZE; i++)
#if defined WRITE_DOUBLE
		dst[i] = src[i];
#elif defined COMPUTE_SIN
		dst[i] = sin(src[i]);
#endif
	RDTSC(t1);
	/*	TSC is 48 bit, set maximum	*/
	COUNTER_VAL(t_min) = 0xFFFFFFFFFFFF;

	/*	do the measurement	*/
	for (j=0; j<REPS; j++)
	{
		RDTSC(t0);
		for (i=0; i<ARRAY_SIZE; i++)
#if defined WRITE_DOUBLE
			dst[i] = src[i];
#elif defined COMPUTE_SIN
			dst[i] = sin(src[i]);
#endif
		RDTSC(t1);
		COUNTER_VAL(t_min) = MIN(COUNTER_VAL(t_min), COUNTER_DIFF(t1, t0));
	}

/*	result	*/
	printf("MODE: %s, REPS=%d, ARRAY_SIZE: %d\ncycles (low 32 bit): %d\n", MODE, REPS, ARRAY_SIZE, (int)COUNTER_LO(t_min));
}