gcc/testsuite/gcc.dg/tree-ssa/loadpre6.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O2 -fdump-tree-pre-stats" } */
   3
   4 union tree_node;
   5 typedef union tree_node *tree;
   6
   7 struct tree_common
   8 {
   9   tree chain;
  10 };
  11
  12 struct tree_list
  13 {
  14   struct tree_common common;
  15   tree value;
  16 };
  17
  18 union tree_node
  19
  20 {
  21   struct tree_common common;
  22   struct tree_list list;
  23 };
  24
  25 extern void abort (void) __attribute__((noreturn));
  26
  27 void __attribute__((noinline))
  28 foo (void)
  29 {
  30   abort ();
  31 }
  32
  33 /* There are some reloaded loads of *cell, and cell->common.chain on various
  34    branches.  */
  35 void __attribute__((noinline))
  36 remove_useless_vars (tree *unexpanded_var_list, int dump_file)
  37 {
  38   tree var, *cell;
  39   int c = 0;
  40   for (cell = unexpanded_var_list; *cell; )
  41     {
  42       var = (*cell)->list.value;
  43       if (var)
  44         {
  45           if (dump_file)
  46             foo ();
  47
  48           *cell = ((*cell)->common.chain);
  49           continue;
  50         }
  51
  52       cell = &((*cell)->common.chain);
  53     }
  54 }
  55 extern void *malloc (__SIZE_TYPE__) __attribute__ ((malloc));
  56
  57 int
  58 main (void)
  59 {
  60   int i;
  61   tree unexpanded_var_list, last = (tree) 0;
  62
  63   for (i = 0; i < 2; i++)
  64     {
  65       unexpanded_var_list = malloc (sizeof (struct tree_list));
  66       unexpanded_var_list->list.value = (tree) (long unsigned) (i & 1);
  67       unexpanded_var_list->common.chain = last;
  68       last = unexpanded_var_list;
  69     }
  70
  71   remove_useless_vars (&unexpanded_var_list, 0);
  72   return 0;
  73 }
  74 /* { dg-final { scan-tree-dump-times "Eliminated: 2" 1 "pre" } } */
  75 /* { dg-final { cleanup-tree-dump "pre" } } */
  76