1  /* { dg-do compile } */
       2  /* { dg-options "-O2 -ftree-loop-distribution -ftree-loop-distribute-patterns -fdump-tree-ldist-details -fdump-tree-optimized" } */
       3  
       4  extern void bar(int);
       5  
       6  void
       7  foo (unsigned i, unsigned n)
       8  {
       9    int a[30];
      10    int b[30];
      11    if (n == 0)
      12      return;
      13    for (i=0; i < n; i++)
      14      a[i] = b[i] = 0;
      15  
      16    while (1)
      17      if (b[0])
      18        bar (a[i - 1]);
      19  }
      20  
      21  /* We should apply loop distribution and generate 1 memset (0).  PRE optimizes
      22     away a[] completely.  */
      23  
      24  /* { dg-final { scan-tree-dump "distributed: split to 0 loops and 1 library calls" "ldist" } } */
      25  /* { dg-final { scan-tree-dump-times "generated memset zero" 1 "ldist" } } */
      26  /* { dg-final { scan-tree-dump-times "int a" 0 "optimized" } } */