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

int main ()
{
  // Init sum
  int sum = 0;
  // Number of iterations
  int n = 100000000;

  struct timeval tv1, tv2;
  long int diff;

  // Start time
  gettimeofday (&tv1, NULL);

  // Loop with Sparc assembly into C source
  asm volatile ("clr %%g1\n\t" 
                "clr %%g2\n\t" 
                "mov %1, %%g1\n" // %1 = input parameter
		"loop:\n\t" 
		"add %%g2, 1, %%g2\n\t" 
		"subcc %%g1, 1, %%g1\n\t" 
		"bne loop\n\t" 
		"nop\n\t" 
		"mov %%g2, %0\n" // %0 = output parameter
		: "=r" (sum)     // output
		: "r" (n)        // input
		: "g1", "g2");   // clobbers

  // End time
  gettimeofday (&tv2, NULL);

  // Compute runtime for loop
  diff = (tv2.tv_sec - tv1.tv_sec) * 1000000L + (tv2.tv_usec - tv1.tv_usec);

  // Print results
  printf ("Elapsed time = %d usec\n", diff);
  printf ("Sum = %ld\n", sum);

  return 0;

}