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 */