1  #define N 100
       2  
       3  void __attribute__ ((noipa))
       4  foo (int *out, int *in, int step)
       5  {
       6    for (int i = 0; i < N; ++i)
       7      {
       8        out[0] = in[i];
       9        out[1] = 2;
      10        out += step;
      11      }
      12  }
      13  
      14  int in[N];
      15  int out[N * 2];
      16  
      17  int
      18  main (void)
      19  {
      20    for (int i = 0; i < N; ++i)
      21      {
      22        in[i] = i * (i + 1);
      23        asm volatile ("" ::: "memory");
      24      }
      25  
      26    foo (out, in, 1);
      27    for (int i = 0; i < N; ++i)
      28      if (out[i] != in[i])
      29        __builtin_abort ();
      30    if (out[N] != 2)
      31      __builtin_abort ();
      32  
      33    foo (out + N - 1, in, -1);
      34    if (out[0] != in[N - 1])
      35      __builtin_abort ();
      36    for (int i = 1; i <= N; ++i)
      37      if (out[i] != 2)
      38        __builtin_abort ();
      39  
      40    return 0;
      41  }
      42  
      43  /* { dg-final { scan-tree-dump-times "LOOP VECTORIZED" 1 "vect" { target { { ! vect_no_align } && vect_int } } } } */