fdtd-2d.c

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/* fdtd-2d.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 "fdtd-2d.h"


/* Array initialization. */
static
void init_array (int tmax,
                 int nx,
                 int ny,
                 DATA_TYPE POLYBENCH_2D(ex,NX,NY,nx,ny),
                 DATA_TYPE POLYBENCH_2D(ey,NX,NY,nx,ny),
                 DATA_TYPE POLYBENCH_2D(hz,NX,NY,nx,ny),
                 DATA_TYPE POLYBENCH_1D(_fict_,TMAX,tmax))
{
  int i, j;

  for (i = 0; i < tmax; i++)
    _fict_[i] = (DATA_TYPE) i;
  for (i = 0; i < nx; i++)
    for (j = 0; j < ny; j++)
      {
        ex[i][j] = ((DATA_TYPE) i*(j+1)) / nx;
        ey[i][j] = ((DATA_TYPE) i*(j+2)) / ny;
        hz[i][j] = ((DATA_TYPE) i*(j+3)) / nx;
      }
}


/* 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 nx,
                 int ny,
                 DATA_TYPE POLYBENCH_2D(ex,NX,NY,nx,ny),
                 DATA_TYPE POLYBENCH_2D(ey,NX,NY,nx,ny),
                 DATA_TYPE POLYBENCH_2D(hz,NX,NY,nx,ny))
{
  int i, j;

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

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

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


/* Main computational kernel. The whole function will be timed,
   including the call and return. */
__attribute__((noinline))
void kernel_fdtd_2d(int tmax,
                    int nx,
                    int ny,
                    DATA_TYPE POLYBENCH_2D(ex,NX,NY,nx,ny),
                    DATA_TYPE POLYBENCH_2D(ey,NX,NY,nx,ny),
                    DATA_TYPE POLYBENCH_2D(hz,NX,NY,nx,ny),
                    DATA_TYPE POLYBENCH_1D(_fict_,TMAX,tmax))
{
  int t, i, j;

#pragma scop

  for(t = 0; t < _PB_TMAX; t++)
    {
      for (j = 0; j < _PB_NY; j++)
        ey[0][j] = _fict_[t];
      for (i = 1; i < _PB_NX; i++)
        for (j = 0; j < _PB_NY; j++)
          ey[i][j] = ey[i][j] - SCALAR_VAL(0.5)*(hz[i][j]-hz[i-1][j]);
      for (i = 0; i < _PB_NX; i++)
        for (j = 1; j < _PB_NY; j++)
          ex[i][j] = ex[i][j] - SCALAR_VAL(0.5)*(hz[i][j]-hz[i][j-1]);
      for (i = 0; i < _PB_NX - 1; i++)
        for (j = 0; j < _PB_NY - 1; j++)
          hz[i][j] = hz[i][j] - SCALAR_VAL(0.7)*  (ex[i][j+1] - ex[i][j] +
                                       ey[i+1][j] - ey[i][j]);
    }

#pragma endscop
}


int main(int argc, char** argv)
{
  /* Retrieve problem size. */
  int tmax = TMAX;
  int nx = NX;
  int ny = NY;

  /* Variable declaration/allocation. */
  POLYBENCH_2D_ARRAY_DECL(ex,DATA_TYPE,NX,NY,nx,ny);
  POLYBENCH_2D_ARRAY_DECL(ey,DATA_TYPE,NX,NY,nx,ny);
  POLYBENCH_2D_ARRAY_DECL(hz,DATA_TYPE,NX,NY,nx,ny);
  POLYBENCH_1D_ARRAY_DECL(_fict_,DATA_TYPE,TMAX,tmax);

  /* Initialize array(s). */
  init_array (tmax, nx, ny,
              POLYBENCH_ARRAY(ex),
              POLYBENCH_ARRAY(ey),
              POLYBENCH_ARRAY(hz),
              POLYBENCH_ARRAY(_fict_));

  /* Start timer. */
  polybench_start_instruments;

  /* Run kernel. */
  kernel_fdtd_2d (tmax, nx, ny,
                  POLYBENCH_ARRAY(ex),
                  POLYBENCH_ARRAY(ey),
                  POLYBENCH_ARRAY(hz),
                  POLYBENCH_ARRAY(_fict_));


  /* 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(nx, ny, POLYBENCH_ARRAY(ex),
                                    POLYBENCH_ARRAY(ey),
                                    POLYBENCH_ARRAY(hz)));

  /* Be clean. */
  POLYBENCH_FREE_ARRAY(ex);
  POLYBENCH_FREE_ARRAY(ey);
  POLYBENCH_FREE_ARRAY(hz);
  POLYBENCH_FREE_ARRAY(_fict_);

  return 0;
}