floyd-warshall.c

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/* floyd-warshall.c: this file is part of PolyBench/C */

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

/* Include polybench common header. */
#include <polybench.h>

/* Include benchmark-specific header. */
#include "floyd-warshall.h"


/* Array initialization. */
static
void init_array (int n,
                 DATA_TYPE POLYBENCH_2D(path,N,N,n,n))
{
  int i, j;

  for (i = 0; i < n; i++)
    for (j = 0; j < n; j++) {
      path[i][j] = i*j%7+1;
      if ((i+j)%13 == 0 || (i+j)%7==0 || (i+j)%11 == 0)
         path[i][j] = 999;
    }
}


/* DCE code. Must scan the entire live-out data.
   Can be used also to check the correctness of the output. */
static
void print_array(int n,
                 DATA_TYPE POLYBENCH_2D(path,N,N,n,n))

{
  int i, j;

  POLYBENCH_DUMP_START;
  POLYBENCH_DUMP_BEGIN("path");
  for (i = 0; i < n; i++)
    for (j = 0; j < n; j++) {
      if ((i * n + j) % 20 == 0) fprintf (POLYBENCH_DUMP_TARGET, "\n");
      fprintf (POLYBENCH_DUMP_TARGET, DATA_PRINTF_MODIFIER, path[i][j]);
    }
  POLYBENCH_DUMP_END("path");
  POLYBENCH_DUMP_FINISH;
}


/* Main computational kernel. The whole function will be timed,
   including the call and return. */
__attribute__((noinline))
void kernel_floyd_warshall(int n,
                           DATA_TYPE POLYBENCH_2D(path,N,N,n,n))
{
  int i, j, k;

#pragma scop
  for (k = 0; k < _PB_N; k++)
    {
      for(i = 0; i < _PB_N; i++)
        for (j = 0; j < _PB_N; j++)
          path[i][j] = path[i][j] < path[i][k] + path[k][j] ?
            path[i][j] : path[i][k] + path[k][j];
    }
#pragma endscop

}


int main(int argc, char** argv)
{
  /* Retrieve problem size. */
  int n = N;

  /* Variable declaration/allocation. */
  POLYBENCH_2D_ARRAY_DECL(path, DATA_TYPE, N, N, n, n);


  /* Initialize array(s). */
  init_array (n, POLYBENCH_ARRAY(path));

  /* Start timer. */
  polybench_start_instruments;

  /* Run kernel. */
  kernel_floyd_warshall (n, POLYBENCH_ARRAY(path));

  /* Stop and print timer. */
  polybench_stop_instruments;
  polybench_print_instruments;

  /* Prevent dead-code elimination. All live-out data must be printed
     by the function call in argument. */
  polybench_prevent_dce(print_array(n, POLYBENCH_ARRAY(path)));

  /* Be clean. */
  POLYBENCH_FREE_ARRAY(path);

  return 0;
}