1 /* { dg-do compile { target { nonpic || pie_enabled } } } */
2 /* { dg-options "-O2 -fdump-tree-pre-stats -fdump-tree-fre1" } */
3 #include <stddef.h>
4 
5 union tree_node;
6 typedef union tree_node *tree;
7 
8 struct tree_common
9 {
10   tree chain;
11 };
12 
13 struct tree_list
14 {
15   struct tree_common common;
16   tree value;
17 };
18 
19 union tree_node
20 
21 {
22   struct tree_common common;
23   struct tree_list list;
24 };
25 
26 extern void abort (void) __attribute__((noreturn));
27 
28 void __attribute__((noinline))
foo(void)29 foo (void)
30 {
31   abort ();
32 }
33 
34 /* There are some reloaded loads of *cell, and cell->common.chain on various
35    branches.  */
36 void __attribute__((noinline))
remove_useless_vars(tree * unexpanded_var_list,int dump_file)37 remove_useless_vars (tree *unexpanded_var_list, int dump_file)
38 {
39   tree var, *cell;
40   int c = 0;
41   for (cell = unexpanded_var_list; *cell; )
42     {
43       var = (*cell)->list.value;
44       if (var)
45         {
46           if (dump_file)
47             foo ();
48 
49           *cell = ((*cell)->common.chain);
50           continue;
51         }
52 
53       cell = &((*cell)->common.chain);
54     }
55 }
56 extern void *malloc (__SIZE_TYPE__) __attribute__ ((malloc));
57 
58 int
main(void)59 main (void)
60 {
61   int i;
62   tree unexpanded_var_list, last = (tree) 0;
63 
64   for (i = 0; i < 2; i++)
65     {
66       unexpanded_var_list = malloc (sizeof (struct tree_list));
67       unexpanded_var_list->list.value = (tree) (ptrdiff_t) (i & 1);
68       unexpanded_var_list->common.chain = last;
69       last = unexpanded_var_list;
70     }
71 
72   remove_useless_vars (&unexpanded_var_list, 0);
73   return 0;
74 }
75 
76 /* { dg-final { scan-tree-dump-not "= unexpanded_var_list;" "fre1" } } */
77 /* { dg-final { scan-tree-dump-times "Eliminated: 1" 1 "pre" } } */
78 /* { dg-final { scan-tree-dump-times "Insertions: 1" 1 "pre" } } */
79