vect-1.c

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/* { dg-do compile } */
/* { dg-require-effective-target vect_int } */
/* { dg-require-effective-target vect_float } */

#define N 16

void fbar (float *);
void ibar (int *);
void sbar (short *);

/* multiple loops */

foo (int n)
{
  float a[N+1];
  float b[N];
  float c[N];
  float d[N];
  int ia[N];
  int ib[N];
  int ic[N];
  short sa[N];
  short sb[N];
  short sc[N];
  int i,j;
  int diff = 0;
  char cb[N];
  char cc[N];
  char image[N][N];
  char block[N][N];

  /* Not vectorizable yet (cross-iteration cycle).  */
  diff = 0;
  for (i = 0; i < N; i++) {
    diff += (cb[i] - cc[i]);
  }
  ibar (&diff);


  /* Not vectorizable yet (outer-loop: not attempted. 
     inner-loop: cross iteration cycle; multi-dimensional arrays).  */
  diff = 0;
  for (i = 0; i < N; i++) {
    for (i = 0; i < N; i++) {
      diff += (image[i][j] - block[i][j]);
    }
  }
  ibar (&diff);


  /* Vectorizable.  */
  for (i = 0; i < N; i++){
    a[i] = b[i];
  }
  fbar (a);


  /* Vectorizable.  */
  for (i = 0; i < N; i++){
    a[i] = b[i] + c[i] + d[i];
  }
  fbar (a);


  /* Not vectorizable yet (access pattern).  */
  for (i = 0; i < N/2; i++){
    a[i] = b[2*i+1] * c[2*i+1] - b[2*i] * c[2*i];
    d[i] = b[2*i] * c[2*i+1] + b[2*i+1] * c[2*i];
  }
  fbar (a);


  /* Vectorizable.  */
  for (i = 0; i < N; i++){
    a[i] = b[i] + c[i];
    d[i] = b[i] + c[i];
    ia[i] = ib[i] + ic[i];
  }
  ibar (ia);
  fbar (a);
  fbar (d);


  /* Not vectorizable yet (two types with different nunits in vector).  */
  for (i = 0; i < N; i++){
    ia[i] = ib[i] + ic[i];
    sa[i] = sb[i] + sc[i];
  }
  ibar (ia);
  sbar (sa);


  /* Not vetorizable yet (too conservative dependence test).  */
  for (i = 0; i < N; i++){
    a[i] = b[i] + c[i];
    a[i+1] = b[i] + c[i];
  }
  fbar (a);
}

/* { dg-final { scan-tree-dump-times "vectorized 3 loops" 1 "vect" } } */
/* { dg-final { scan-tree-dump-times "Vectorizing an unaligned access" 0 "vect" } } */
/* { dg-final { cleanup-tree-dump "vect" } } */