1 /* Callgraph construction.
2 Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
3 Contributed by Jan Hubicka
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
24 #include "coretypes.h"
27 #include "tree-flow.h"
28 #include "langhooks.h"
29 #include "pointer-set.h"
32 #include "tree-gimple.h"
33 #include "tree-pass.h"
35 /* Walk tree and record all calls and references to functions/variables.
36 Called via walk_tree: TP is pointer to tree to be examined. */
39 record_reference (tree
*tp
, int *walk_subtrees
, void *data
)
43 switch (TREE_CODE (t
))
46 if (TREE_STATIC (t
) || DECL_EXTERNAL (t
))
48 varpool_mark_needed_node (varpool_node (t
));
49 if (lang_hooks
.callgraph
.analyze_expr
)
50 return lang_hooks
.callgraph
.analyze_expr (tp
, walk_subtrees
,
57 if (flag_unit_at_a_time
)
59 /* Record dereferences to the functions. This makes the
60 functions reachable unconditionally. */
61 tree decl
= TREE_OPERAND (*tp
, 0);
62 if (TREE_CODE (decl
) == FUNCTION_DECL
)
63 cgraph_mark_needed_node (cgraph_node (decl
));
68 /* Save some cycles by not walking types and declaration as we
69 won't find anything useful there anyway. */
70 if (IS_TYPE_OR_DECL_P (*tp
))
76 if ((unsigned int) TREE_CODE (t
) >= LAST_AND_UNUSED_TREE_CODE
)
77 return lang_hooks
.callgraph
.analyze_expr (tp
, walk_subtrees
, data
);
84 /* Give initial reasons why inlining would fail on all calls from
85 NODE. Those get either nullified or usually overwritten by more precise
89 initialize_inline_failed (struct cgraph_node
*node
)
91 struct cgraph_edge
*e
;
93 for (e
= node
->callers
; e
; e
= e
->next_caller
)
95 gcc_assert (!e
->callee
->global
.inlined_to
);
96 gcc_assert (e
->inline_failed
);
97 if (node
->local
.redefined_extern_inline
)
98 e
->inline_failed
= N_("redefined extern inline functions are not "
99 "considered for inlining");
100 else if (!node
->local
.inlinable
)
101 e
->inline_failed
= N_("function not inlinable");
102 else if (CALL_CANNOT_INLINE_P (e
->call_stmt
))
103 e
->inline_failed
= N_("mismatched arguments");
105 e
->inline_failed
= N_("function not considered for inlining");
109 /* Create cgraph edges for function calls.
110 Also look for functions and variables having addresses taken. */
113 build_cgraph_edges (void)
116 struct cgraph_node
*node
= cgraph_node (current_function_decl
);
117 struct pointer_set_t
*visited_nodes
= pointer_set_create ();
118 block_stmt_iterator bsi
;
120 int entry_freq
= ENTRY_BLOCK_PTR
->frequency
;
125 /* Create the callgraph edges and record the nodes referenced by the function.
128 for (bsi
= bsi_start (bb
); !bsi_end_p (bsi
); bsi_next (&bsi
))
130 tree stmt
= bsi_stmt (bsi
);
131 tree call
= get_call_expr_in (stmt
);
134 if (call
&& (decl
= get_callee_fndecl (call
)))
137 int n
= call_expr_nargs (call
);
138 int freq
= (!bb
->frequency
&& !entry_freq
? CGRAPH_FREQ_BASE
139 : bb
->frequency
* CGRAPH_FREQ_BASE
/ entry_freq
);
140 if (freq
> CGRAPH_FREQ_MAX
)
141 freq
= CGRAPH_FREQ_MAX
;
142 cgraph_create_edge (node
, cgraph_node (decl
), stmt
,
145 for (i
= 0; i
< n
; i
++)
146 walk_tree (&CALL_EXPR_ARG (call
, i
),
147 record_reference
, node
, visited_nodes
);
148 if (TREE_CODE (stmt
) == GIMPLE_MODIFY_STMT
)
149 walk_tree (&GIMPLE_STMT_OPERAND (stmt
, 0),
150 record_reference
, node
, visited_nodes
);
153 walk_tree (bsi_stmt_ptr (bsi
), record_reference
, node
, visited_nodes
);
156 /* Look for initializers of constant variables and private statics. */
157 for (step
= cfun
->unexpanded_var_list
;
159 step
= TREE_CHAIN (step
))
161 tree decl
= TREE_VALUE (step
);
162 if (TREE_CODE (decl
) == VAR_DECL
163 && (TREE_STATIC (decl
) && !DECL_EXTERNAL (decl
))
164 && flag_unit_at_a_time
)
165 varpool_finalize_decl (decl
);
166 else if (TREE_CODE (decl
) == VAR_DECL
&& DECL_INITIAL (decl
))
167 walk_tree (&DECL_INITIAL (decl
), record_reference
, node
, visited_nodes
);
170 pointer_set_destroy (visited_nodes
);
171 initialize_inline_failed (node
);
175 struct tree_opt_pass pass_build_cgraph_edges
=
179 build_cgraph_edges
, /* execute */
182 0, /* static_pass_number */
184 PROP_cfg
, /* properties_required */
185 0, /* properties_provided */
186 0, /* properties_destroyed */
187 0, /* todo_flags_start */
188 0, /* todo_flags_finish */
192 /* Record references to functions and other variables present in the
193 initial value of DECL, a variable. */
196 record_references_in_initializer (tree decl
)
198 struct pointer_set_t
*visited_nodes
= pointer_set_create ();
199 walk_tree (&DECL_INITIAL (decl
), record_reference
, NULL
, visited_nodes
);
200 pointer_set_destroy (visited_nodes
);
203 /* Rebuild cgraph edges for current function node. This needs to be run after
204 passes that don't update the cgraph. */
207 rebuild_cgraph_edges (void)
210 struct cgraph_node
*node
= cgraph_node (current_function_decl
);
211 block_stmt_iterator bsi
;
212 int entry_freq
= ENTRY_BLOCK_PTR
->frequency
;
217 cgraph_node_remove_callees (node
);
219 node
->count
= ENTRY_BLOCK_PTR
->count
;
222 for (bsi
= bsi_start (bb
); !bsi_end_p (bsi
); bsi_next (&bsi
))
224 tree stmt
= bsi_stmt (bsi
);
225 tree call
= get_call_expr_in (stmt
);
228 if (call
&& (decl
= get_callee_fndecl (call
)))
230 int freq
= (!bb
->frequency
&& !entry_freq
? CGRAPH_FREQ_BASE
231 : bb
->frequency
* CGRAPH_FREQ_BASE
/ entry_freq
);
232 if (freq
> CGRAPH_FREQ_MAX
)
233 freq
= CGRAPH_FREQ_MAX
;
234 cgraph_create_edge (node
, cgraph_node (decl
), stmt
,
235 bb
->count
, freq
, bb
->loop_depth
);
238 initialize_inline_failed (node
);
239 gcc_assert (!node
->global
.inlined_to
);
243 struct tree_opt_pass pass_rebuild_cgraph_edges
=
247 rebuild_cgraph_edges
, /* execute */
250 0, /* static_pass_number */
252 PROP_cfg
, /* properties_required */
253 0, /* properties_provided */
254 0, /* properties_destroyed */
255 0, /* todo_flags_start */
256 0, /* todo_flags_finish */