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/* { dg-do compile { target nonpic } } */
/* { dg-options "-O2 -fdump-tree-pre-stats -fdump-tree-fre1" } */
#include <stddef.h>
union tree_node;
typedef union tree_node *tree;
struct tree_common
{
tree chain;
};
struct tree_list
{
struct tree_common common;
tree value;
};
union tree_node
{
struct tree_common common;
struct tree_list list;
};
extern void abort (void) __attribute__((noreturn));
void __attribute__((noinline))
foo (void)
{
abort ();
}
/* There are some reloaded loads of *cell, and cell->common.chain on various
branches. */
void __attribute__((noinline))
remove_useless_vars (tree *unexpanded_var_list, int dump_file)
{
tree var, *cell;
int c = 0;
for (cell = unexpanded_var_list; *cell; )
{
var = (*cell)->list.value;
if (var)
{
if (dump_file)
foo ();
*cell = ((*cell)->common.chain);
continue;
}
cell = &((*cell)->common.chain);
}
}
extern void *malloc (__SIZE_TYPE__) __attribute__ ((malloc));
int
main (void)
{
int i;
tree unexpanded_var_list, last = (tree) 0;
for (i = 0; i < 2; i++)
{
unexpanded_var_list = malloc (sizeof (struct tree_list));
unexpanded_var_list->list.value = (tree) (ptrdiff_t) (i & 1);
unexpanded_var_list->common.chain = last;
last = unexpanded_var_list;
}
remove_useless_vars (&unexpanded_var_list, 0);
return 0;
}
/* { dg-final { scan-tree-dump-not "= unexpanded_var_list;" "fre1" } } */
/* { dg-final { scan-tree-dump-times "Eliminated: 1" 1 "pre" } } */
/* { dg-final { scan-tree-dump-times "Insertions: 2" 1 "pre" } } */
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