1  /* { dg-do run } */
       2  /* { dg-require-effective-target store_merge } */
       3  /* { dg-options "-O2 -fdump-tree-store-merging" } */
       4  
       5  struct bar
       6  {
       7    int a;
       8    unsigned char b;
       9    unsigned char c;
      10    short d;
      11    unsigned char e;
      12    unsigned char f;
      13    unsigned char g;
      14  };
      15  
      16  __attribute__ ((noinline)) void
      17  foozero (struct bar *p)
      18  {
      19    p->b = 0;
      20    p->a = 0;
      21    p->c = 0;
      22    p->d = 0;
      23    p->e = 0;
      24    p->f = 0;
      25    p->g = 0;
      26  }
      27  
      28  __attribute__ ((noinline)) void
      29  foo1 (struct bar *p)
      30  {
      31    p->b = 1;
      32    p->a = 2;
      33    p->c = 3;
      34    p->d = 4;
      35    p->e = 5;
      36    p->f = 0;
      37    p->g = 0xff;
      38  }
      39  
      40  __attribute__ ((noinline)) void
      41  foo2 (struct bar *p, struct bar *p2)
      42  {
      43    p->b = 0xff;
      44    p2->b = 0xa;
      45    p->a = 0xfffff;
      46    p2->c = 0xc;
      47    p->c = 0xff;
      48    p2->d = 0xbf;
      49    p->d = 0xfff;
      50  }
      51  
      52  int
      53  main (void)
      54  {
      55    struct bar b1, b2;
      56    foozero (&b1);
      57    foozero (&b2);
      58  
      59    foo1 (&b1);
      60    if (b1.b != 1 || b1.a != 2 || b1.c != 3 || b1.d != 4 || b1.e != 5
      61        || b1.f != 0 || b1.g != 0xff)
      62      __builtin_abort ();
      63  
      64    foozero (&b1);
      65    /* Make sure writes to aliasing struct pointers preserve the
      66       correct order.  */
      67    foo2 (&b1, &b1);
      68    if (b1.b != 0xa || b1.a != 0xfffff || b1.c != 0xff || b1.d != 0xfff)
      69      __builtin_abort ();
      70  
      71    foozero (&b1);
      72    foo2 (&b1, &b2);
      73    if (b1.a != 0xfffff || b1.b != 0xff || b1.c != 0xff || b1.d != 0xfff
      74        || b2.b != 0xa || b2.c != 0xc || b2.d != 0xbf)
      75      __builtin_abort ();
      76  
      77    return 0;
      78  }
      79  
      80  /* { dg-final { scan-tree-dump-times "Merging successful" 2 "store-merging" } } */