/* Exception handling semantics and decomposition for trees.
- Copyright (C) 2003 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
This file is part of GCC.
we get to rtl. Once we're done with lowering here, if we lose
the information there's no way to recover it!
- (2) There are many more statements that *cannot* throw as
+ (2) There are many more statements that *cannot* throw as
compared to those that can. We should be saving some amount
of space by only allocating memory for those that can throw. */
n->region_nr = get_eh_region_number (region);
slot = htab_find_slot (throw_stmt_table, n, INSERT);
- if (*slot)
- abort ();
+ gcc_assert (!*slot);
*slot = n;
}
struct throw_stmt_node *n;
void **slot;
- if (num < 0)
- abort ();
+ gcc_assert (num >= 0);
n = ggc_alloc (sizeof (*n));
n->stmt = t;
n->region_nr = num;
slot = htab_find_slot (throw_stmt_table, n, INSERT);
- if (*slot)
- abort ();
+ gcc_assert (!*slot);
*slot = n;
}
n->parent = parent;
slot = htab_find_slot (finally_tree, n, INSERT);
- if (*slot)
- abort ();
+ gcc_assert (!*slot);
*slot = n;
}
struct leh_state
{
- /* What's "current" while constructing the eh region tree. These
+ /* What's "current" while constructing the eh region tree. These
correspond to variables of the same name in cfun->eh, which we
don't have easy access to. */
struct eh_region *cur_region;
struct leh_tf_state
{
/* Pointer to the TRY_FINALLY node under discussion. The try_finally_expr
- is the original TRY_FINALLY_EXPR. We need to retain this so that
+ is the original TRY_FINALLY_EXPR. We need to retain this so that
outside_finally_tree can reliably reference the tree used in the
collect_finally_tree data structures. */
tree try_finally_expr;
though subsequent transformations may have cleared that flag. */
tree fallthru_label;
- /* A label that has been registered with except.c to be the
+ /* A label that has been registered with except.c to be the
landing pad for this try block. */
tree eh_label;
static void lower_eh_filter (struct leh_state *, tree *);
static void lower_eh_constructs_1 (struct leh_state *, tree *);
-/* Comparison function for qsort/bsearch. We're interested in
+/* Comparison function for qsort/bsearch. We're interested in
searching goto queue elements for source statements. */
static int
tsi_link_after (tsi, new, TSI_CONTINUE_LINKING);
}
-/* The real work of replace_goto_queue. Returns with TSI updated to
+/* The real work of replace_goto_queue. Returns with TSI updated to
point to the next statement. */
static void replace_goto_queue_stmt_list (tree, struct leh_tf_state *);
break;
case STATEMENT_LIST:
- abort ();
+ gcc_unreachable ();
default:
/* These won't have gotos in them. */
static void
replace_goto_queue (struct leh_tf_state *tf)
{
+ if (tf->goto_queue_active == 0)
+ return;
replace_goto_queue_stmt_list (*tf->top_p, tf);
}
{
tree lab = GOTO_DESTINATION (stmt);
- /* Computed and non-local gotos do not get processed. Given
+ /* Computed and non-local gotos do not get processed. Given
their nature we can neither tell whether we've escaped the
finally block nor redirect them if we knew. */
if (TREE_CODE (lab) != LABEL_DECL)
/* No need to record gotos that don't leave the try block. */
if (! outside_finally_tree (lab, tf->try_finally_expr))
return;
-
+
if (! tf->dest_array)
{
VARRAY_TREE_INIT (tf->dest_array, 10, "dest_array");
break;
default:
- abort ();
+ gcc_unreachable ();
}
active = tf->goto_queue_active;
q = &tf->goto_queue[active];
tf->goto_queue_active = active + 1;
-
+
memset (q, 0, sizeof (*q));
q->stmt = stmt;
q->index = index;
for (i = 0; i < n; ++i)
{
tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i));
- if (outside_finally_tree (lab, tf->try_finally_expr))
- abort ();
+ gcc_assert (!outside_finally_tree (lab, tf->try_finally_expr));
}
}
#else
depends, I guess, but it does make generation of the switch in
lower_try_finally_switch easier. */
- if (TREE_CODE (ret_expr) == RESULT_DECL)
+ switch (TREE_CODE (ret_expr))
{
+ case RESULT_DECL:
if (!*return_value_p)
*return_value_p = ret_expr;
- else if (*return_value_p != ret_expr)
- abort ();
- q->cont_stmt = q->stmt;
- }
- else if (TREE_CODE (ret_expr) == MODIFY_EXPR)
- {
- tree result = TREE_OPERAND (ret_expr, 0);
- tree new, old = TREE_OPERAND (ret_expr, 1);
-
- if (!*return_value_p)
- {
- if (aggregate_value_p (TREE_TYPE (result),
- TREE_TYPE (current_function_decl)))
- /* If this function returns in memory, copy the argument
- into the return slot now. Otherwise, we might need to
- worry about magic return semantics, so we need to use a
- temporary to hold the value until we're actually ready
- to return. */
- new = result;
- else
- new = create_tmp_var (TREE_TYPE (old), "rettmp");
- *return_value_p = new;
- }
else
- new = *return_value_p;
+ gcc_assert (*return_value_p == ret_expr);
+ q->cont_stmt = q->stmt;
+ break;
- x = build (MODIFY_EXPR, TREE_TYPE (new), new, old);
- append_to_statement_list (x, &q->repl_stmt);
+ case MODIFY_EXPR:
+ {
+ tree result = TREE_OPERAND (ret_expr, 0);
+ tree new, old = TREE_OPERAND (ret_expr, 1);
+
+ if (!*return_value_p)
+ {
+ if (aggregate_value_p (TREE_TYPE (result),
+ TREE_TYPE (current_function_decl)))
+ /* If this function returns in memory, copy the argument
+ into the return slot now. Otherwise, we might need to
+ worry about magic return semantics, so we need to use a
+ temporary to hold the value until we're actually ready
+ to return. */
+ new = result;
+ else
+ new = create_tmp_var (TREE_TYPE (old), "rettmp");
+ *return_value_p = new;
+ }
+ else
+ new = *return_value_p;
+
+ x = build (MODIFY_EXPR, TREE_TYPE (new), new, old);
+ append_to_statement_list (x, &q->repl_stmt);
+
+ if (new == result)
+ x = result;
+ else
+ x = build (MODIFY_EXPR, TREE_TYPE (result), result, new);
+ q->cont_stmt = build1 (RETURN_EXPR, void_type_node, x);
+ }
- if (new == result)
- x = result;
- else
- x = build (MODIFY_EXPR, TREE_TYPE (result), result, new);
- q->cont_stmt = build1 (RETURN_EXPR, void_type_node, x);
+ default:
+ gcc_unreachable ();
}
- else
- abort ();
}
else
{
{
tree region = NULL;
- t = lhd_unsave_expr_now (t);
+ t = unsave_expr_now (t);
if (outer_state->tf)
region = outer_state->tf->try_finally_expr;
label = create_artificial_label ();
tf->fallthru_label = label;
if (tf->outer->tf)
- record_in_finally_tree (label, tf->outer->tf->try_finally_expr);
+ record_in_finally_tree (label, tf->outer->tf->try_finally_expr);
}
return label;
}
where "fintmp" is the temporary used in the switch statement generation
alternative considered below. For the nonce, we always choose the first
- option.
+ option.
- THIS_STATE may be null if if this is a try-cleanup, not a try-finally. */
+ THIS_STATE may be null if this is a try-cleanup, not a try-finally. */
static void
honor_protect_cleanup_actions (struct leh_state *outer_state,
tsi_link_after (&i, x, TSI_CONTINUE_LINKING);
x = build1 (RESX_EXPR, void_type_node,
- build_int_2 (get_eh_region_number (tf->region), 0));
+ build_int_cst (NULL_TREE,
+ get_eh_region_number (tf->region)));
tsi_link_after (&i, x, TSI_CONTINUE_LINKING);
}
append_to_statement_list (x, tf->top_p);
append_to_statement_list (finally, tf->top_p);
-
+
x = build1 (RESX_EXPR, void_type_node,
- build_int_2 (get_eh_region_number (tf->region), 0));
+ build_int_cst (NULL_TREE,
+ get_eh_region_number (tf->region)));
append_to_statement_list (x, tf->top_p);
return;
for (; q < qe; ++q)
do_goto_redirection (q, finally_label, NULL);
replace_goto_queue (tf);
-
+
if (VARRAY_TREE (tf->dest_array, 0) == tf->fallthru_label)
{
/* Reachable by goto to fallthru label only. Redirect it
append_to_statement_list (x, &new_stmt);
x = build1 (RESX_EXPR, void_type_node,
- build_int_2 (get_eh_region_number (tf->region), 0));
+ build_int_cst (NULL_TREE,
+ get_eh_region_number (tf->region)));
append_to_statement_list (x, &new_stmt);
}
if (tf->may_fallthru)
{
x = build (MODIFY_EXPR, void_type_node, finally_tmp,
- build_int_2 (fallthru_index, 0));
+ build_int_cst (NULL_TREE, fallthru_index));
append_to_statement_list (x, tf->top_p);
if (tf->may_throw)
last_case = build (CASE_LABEL_EXPR, void_type_node,
- build_int_2 (fallthru_index, 0), NULL,
+ build_int_cst (NULL_TREE, fallthru_index), NULL,
create_artificial_label ());
TREE_VEC_ELT (case_label_vec, last_case_index) = last_case;
last_case_index++;
append_to_statement_list (x, tf->top_p);
x = build (MODIFY_EXPR, void_type_node, finally_tmp,
- build_int_2 (eh_index, 0));
+ build_int_cst (NULL_TREE, eh_index));
append_to_statement_list (x, tf->top_p);
last_case = build (CASE_LABEL_EXPR, void_type_node,
- build_int_2 (eh_index, 0), NULL,
+ build_int_cst (NULL_TREE, eh_index), NULL,
create_artificial_label ());
TREE_VEC_ELT (case_label_vec, last_case_index) = last_case;
last_case_index++;
x = build (LABEL_EXPR, void_type_node, CASE_LABEL (last_case));
append_to_statement_list (x, &switch_body);
x = build1 (RESX_EXPR, void_type_node,
- build_int_2 (get_eh_region_number (tf->region), 0));
+ build_int_cst (NULL_TREE,
+ get_eh_region_number (tf->region)));
append_to_statement_list (x, &switch_body);
}
if (q->index < 0)
{
mod = build (MODIFY_EXPR, void_type_node, finally_tmp,
- build_int_2 (return_index, 0));
+ build_int_cst (NULL_TREE, return_index));
do_return_redirection (q, finally_label, mod, &return_val);
switch_id = return_index;
}
else
{
mod = build (MODIFY_EXPR, void_type_node, finally_tmp,
- build_int_2 (q->index, 0));
+ build_int_cst (NULL_TREE, q->index));
do_goto_redirection (q, finally_label, mod);
switch_id = q->index;
}
if (!TREE_VEC_ELT (case_label_vec, case_index))
{
last_case = build (CASE_LABEL_EXPR, void_type_node,
- build_int_2 (switch_id, 0), NULL,
+ build_int_cst (NULL_TREE, switch_id), NULL,
create_artificial_label ());
TREE_VEC_ELT (case_label_vec, case_index) = last_case;
/* A subroutine of lower_eh_constructs_1. Lower a TRY_FINALLY_EXPR nodes
to a sequence of labels and blocks, plus the exception region trees
- that record all the magic. This is complicated by the need to
+ that record all the magic. This is complicated by the need to
arrange for the FINALLY block to be executed on all exits. */
static void
}
/* A subroutine of lower_eh_constructs_1. Lower a TRY_CATCH_EXPR with a
- list of CATCH_EXPR nodes to a sequence of labels and blocks, plus the
+ list of CATCH_EXPR nodes to a sequence of labels and blocks, plus the
exception region trees that record all the magic. */
static void
struct eh_region *this_region;
tree inner = expr_first (TREE_OPERAND (*tp, 1));
tree eh_label;
-
+
if (EH_FILTER_MUST_NOT_THROW (inner))
this_region = gen_eh_region_must_not_throw (state->cur_region);
else
EH_FILTER_TYPES (inner));
this_state = *state;
this_state.cur_region = this_region;
-
+
lower_eh_constructs_1 (&this_state, &TREE_OPERAND (*tp, 0));
if (!get_eh_region_may_contain_throw (this_region))
record_stmt_eh_region (state->cur_region, t);
note_eh_region_may_contain_throw (state->cur_region);
- /* ??? For the benefit of calls.c, converting all this to rtl,
+ /* ??? For the benefit of calls.c, converting all this to rtl,
we need to record the call expression, not just the outer
modify statement. */
op = get_call_expr_in (t);
collect_eh_region_array ();
}
-struct tree_opt_pass pass_lower_eh =
+struct tree_opt_pass pass_lower_eh =
{
"eh", /* name */
NULL, /* gate */
PROP_gimple_leh, /* properties_provided */
PROP_gimple_lcf, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_func /* todo_flags_finish */
+ TODO_dump_func, /* todo_flags_finish */
+ 0 /* letter */
};
\f
make_edge (src, dst, EDGE_ABNORMAL | EDGE_EH);
}
-
+
void
make_eh_edges (tree stmt)
{
bool honor_snans = false;
bool fp_operation = false;
bool honor_trapv = false;
- tree t, base, idx;
+ tree t, base;
- if (TREE_CODE_CLASS (code) == '<'
- || TREE_CODE_CLASS (code) == '1'
- || TREE_CODE_CLASS (code) == '2')
+ if (TREE_CODE_CLASS (code) == tcc_comparison
+ || TREE_CODE_CLASS (code) == tcc_unary
+ || TREE_CODE_CLASS (code) == tcc_binary)
{
t = TREE_TYPE (expr);
fp_operation = FLOAT_TYPE_P (t);
case ARRAY_REF:
base = TREE_OPERAND (expr, 0);
- idx = TREE_OPERAND (expr, 1);
if (tree_could_trap_p (base))
return true;
return !in_array_bounds_p (expr);
case INDIRECT_REF:
+ case ALIGN_INDIRECT_REF:
+ case MISALIGNED_INDIRECT_REF:
return !TREE_THIS_NOTRAP (expr);
case ASM_EXPR:
return true;
return false;
+ case CALL_EXPR:
+ t = get_callee_fndecl (expr);
+ /* Assume that calls to weak functions may trap. */
+ if (!t || !DECL_P (t) || DECL_WEAK (t))
+ return true;
+ return false;
+
default:
/* Any floating arithmetic may trap. */
if (fp_operation && flag_trapping_math)
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