tree
pop_stmt_list (tree t)
{
tree u = NULL_TREE;
/* Pop statement lists until we reach the target level. The extra
nestings will be due to outstanding cleanups. */
while (1)
{
u = stmt_list_stack->pop ();
if (!stmt_list_stack->is_empty ())
{
tree x = stmt_list_stack->last ();
STATEMENT_LIST_HAS_LABEL (x) |= STATEMENT_LIST_HAS_LABEL (u);
}
if (t == u)
break;
}
gcc_assert (u != NULL_TREE);
/* If the statement list is completely empty, just return it. This is
just as good small as build_empty_stmt, with the advantage that
statement lists are merged when they appended to one another. So
using the STATEMENT_LIST avoids pathological buildup of EMPTY_STMT_P
statements. */
if (TREE_SIDE_EFFECTS (t))
{
tree_stmt_iterator i = tsi_start (t);
/* If the statement list contained exactly one statement, then
extract it immediately. */
if (tsi_one_before_end_p (i))
{
u = tsi_stmt (i);
tsi_delink (&i);
free_stmt_list (t);
t = u;
}
}
return t;
}
void
tsi_link_before (tree_stmt_iterator *i, tree t, enum tsi_iterator_update mode)
{
struct tree_statement_list_node *head, *tail, *cur;
/* Die on looping. */
gcc_assert (t != i->container);
if (TREE_CODE (t) == STATEMENT_LIST)
{
head = STATEMENT_LIST_HEAD (t);
tail = STATEMENT_LIST_TAIL (t);
STATEMENT_LIST_HEAD (t) = NULL;
STATEMENT_LIST_TAIL (t) = NULL;
free_stmt_list (t);
/* Empty statement lists need no work. */
if (!head || !tail)
{
gcc_assert (head == tail);
return;
}
}
else
{
head = ggc_alloc (sizeof (*head));
head->prev = NULL;
head->next = NULL;
head->stmt = t;
tail = head;
}
TREE_SIDE_EFFECTS (i->container) = 1;
cur = i->ptr;
/* Link it into the list. */
if (cur)
{
head->prev = cur->prev;
if (head->prev)
head->prev->next = head;
else
STATEMENT_LIST_HEAD (i->container) = head;
tail->next = cur;
cur->prev = tail;
}
else
{
head->prev = STATEMENT_LIST_TAIL (i->container);
if (head->prev)
head->prev->next = head;
else
STATEMENT_LIST_HEAD (i->container) = head;
STATEMENT_LIST_TAIL (i->container) = tail;
}
/* Update the iterator, if requested. */
switch (mode)
{
case TSI_NEW_STMT:
case TSI_CONTINUE_LINKING:
case TSI_CHAIN_START:
i->ptr = head;
break;
case TSI_CHAIN_END:
i->ptr = tail;
break;
case TSI_SAME_STMT:
break;
}
}
