plain.c

gistfile1.c

#include <stdlib.h>
#include <stdio.h>
#include <sys/time.h>

#define SIZE (4*1000)

void double_elements(unsigned int *ptr, unsigned int size);

int main(void)
{	
	struct timeval tv1,tv2;
	unsigned int i;
	unsigned int  input_array[SIZE];
	
	
	for(i=0;i<SIZE;i++)
	{
		input_array[i]=i+1;
#ifdef DEBUG
		printf("Input:%d\n",input_array[i]);
#endif
	}
	gettimeofday(&tv1,NULL);
	double_elements(input_array,SIZE);
	gettimeofday(&tv2,NULL);
        printf("\n");
#ifdef DEBUG
	for(i=0;i<SIZE;i++)
		printf("Output:%d\n",input_array[i]);
#endif
	printf("Time for compute : %d microseconds\n", tv2.tv_usec - tv1.tv_usec +1000000 * (tv2.tv_sec - tv1.tv_sec));

	return 0;
	
}

void  double_elements(unsigned int *ptr, unsigned int size)
{
	unsigned int loop;
	for( loop= 0; loop<size; loop++)
		ptr[loop]<<=1;
	return;
}

arm-v7a8-linux-gnueabi-gcc plain.c -o plain