gcc/testsuite/gcc.dg/tree-ssa/pta-escape-3.c

   1 /* { dg-do run } */
   2 /* { dg-options "-O -fdump-tree-alias-details -fdelete-null-pointer-checks" } */
   3
   4 int *i;
   5 void __attribute__((noinline))
   6 foo (void)
   7 {
   8   *i = 1;
   9 }
  10 int **__attribute__((noinline,const))
  11 foobar (void)
  12 {
  13   return &i;
  14 }
  15 int __attribute__((noinline))
  16 bar(int local_p)
  17 {
  18   int x = 0;
  19   int *j;
  20   int **p;
  21   if (local_p)
  22     p = &j;
  23   else
  24     p = foobar();
  25   *p = &x;  /* This makes x escape.  */
  26   foo ();
  27   return x;
  28 }
  29 extern void abort (void);
  30 int main()
  31 {
  32   int k = 2;
  33   i = &k;
  34   if (bar (1) != 0 || k != 1)
  35     abort ();
  36   if (bar (0) != 1)
  37     abort ();
  38   return 0;
  39 }
  40
  41 /* { dg-final { scan-tree-dump "ESCAPED = { NULL ESCAPED NONLOCAL x }" "alias" { target { ! keeps_null_pointer_checks } } } } */
  42 /* { dg-final { scan-tree-dump "ESCAPED = { ESCAPED NONLOCAL x }" "alias" { target { keeps_null_pointer_checks } } } } */