gcc/testsuite/gcc.dg/20040305-1.c

   1
   2 /* The testcase failed due to corrupted alias information.
   3    During the crossjump analyzing step the mem alias info of the
   4    st instructions are merged and get copied during basic block
   5    reordering which leads to an insn with wrong alias info.
   6    The scheduler afterwards exchanges the mvc and st instructions
   7    not recognizing the anti dependence.  */
   8 /* { dg-do run { target s390-*-* } } */
   9 /* { dg-options "-O3 -mtune=z990 -fno-inline" } */
  10
  11 extern void exit (int);
  12 extern void abort (void);
  13
  14 int f;
  15 int g;
  16 int h;
  17
  18 int* x  = &f;
  19 int* p1 = &g;
  20 int* p2 = &h;
  21
  22 int
  23 foo(void)
  24 {
  25
  26   if (*x == 0)
  27     {
  28       x = p1;         /* mvc - memory to memory */
  29       p1 = (int*)0;   /* st  - register to memory */
  30       return 1;
  31     }
  32   if (*x == 5)
  33     {
  34       f = 1;
  35       g = 2;
  36
  37       p2 = (int*)0;   /* st */
  38       return 1;
  39     }
  40 }
  41
  42 int
  43 main (int argc, char** argv)
  44 {
  45   foo ();
  46
  47   /* If the scheduler has exchanged the mvc and st instructions,
  48      x is 0. The expected result is &g.  */
  49   if (x == &g)
  50     exit (0);
  51   else
  52     abort ();
  53 }