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 3, 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 COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
23 #include "coretypes.h"
26 #include "tree-flow.h"
27 #include "langhooks.h"
28 #include "pointer-set.h"
31 #include "tree-gimple.h"
32 #include "tree-pass.h"
34 /* Walk tree and record all calls and references to functions/variables.
35 Called via walk_tree: TP is pointer to tree to be examined. */
38 record_reference (tree *tp, int *walk_subtrees, void *data)
42 switch (TREE_CODE (t))
45 if (TREE_STATIC (t) || DECL_EXTERNAL (t))
47 varpool_mark_needed_node (varpool_node (t));
48 if (lang_hooks.callgraph.analyze_expr)
49 return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees,
56 if (flag_unit_at_a_time)
58 /* Record dereferences to the functions. This makes the
59 functions reachable unconditionally. */
60 tree decl = TREE_OPERAND (*tp, 0);
61 if (TREE_CODE (decl) == FUNCTION_DECL)
62 cgraph_mark_needed_node (cgraph_node (decl));
67 /* Save some cycles by not walking types and declaration as we
68 won't find anything useful there anyway. */
69 if (IS_TYPE_OR_DECL_P (*tp))
75 if ((unsigned int) TREE_CODE (t) >= LAST_AND_UNUSED_TREE_CODE)
76 return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees, data);
83 /* Give initial reasons why inlining would fail on all calls from
84 NODE. Those get either nullified or usually overwritten by more precise
88 initialize_inline_failed (struct cgraph_node *node)
90 struct cgraph_edge *e;
92 for (e = node->callers; e; e = e->next_caller)
94 gcc_assert (!e->callee->global.inlined_to);
95 gcc_assert (e->inline_failed);
96 if (node->local.redefined_extern_inline)
97 e->inline_failed = N_("redefined extern inline functions are not "
98 "considered for inlining");
99 else if (!node->local.inlinable)
100 e->inline_failed = N_("function not inlinable");
101 else if (CALL_CANNOT_INLINE_P (e->call_stmt))
102 e->inline_failed = N_("mismatched arguments");
104 e->inline_failed = N_("function not considered for inlining");
108 /* Create cgraph edges for function calls.
109 Also look for functions and variables having addresses taken. */
112 build_cgraph_edges (void)
115 struct cgraph_node *node = cgraph_node (current_function_decl);
116 struct pointer_set_t *visited_nodes = pointer_set_create ();
117 block_stmt_iterator bsi;
119 int entry_freq = ENTRY_BLOCK_PTR->frequency;
124 /* Create the callgraph edges and record the nodes referenced by the function.
127 for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
129 tree stmt = bsi_stmt (bsi);
130 tree call = get_call_expr_in (stmt);
133 if (call && (decl = get_callee_fndecl (call)))
136 int n = call_expr_nargs (call);
137 int freq = (!bb->frequency && !entry_freq ? CGRAPH_FREQ_BASE
138 : bb->frequency * CGRAPH_FREQ_BASE / entry_freq);
139 if (freq > CGRAPH_FREQ_MAX)
140 freq = CGRAPH_FREQ_MAX;
141 cgraph_create_edge (node, cgraph_node (decl), stmt,
144 for (i = 0; i < n; i++)
145 walk_tree (&CALL_EXPR_ARG (call, i),
146 record_reference, node, visited_nodes);
147 if (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT)
148 walk_tree (&GIMPLE_STMT_OPERAND (stmt, 0),
149 record_reference, node, visited_nodes);
152 walk_tree (bsi_stmt_ptr (bsi), record_reference, node, visited_nodes);
155 /* Look for initializers of constant variables and private statics. */
156 for (step = cfun->unexpanded_var_list;
158 step = TREE_CHAIN (step))
160 tree decl = TREE_VALUE (step);
161 if (TREE_CODE (decl) == VAR_DECL
162 && (TREE_STATIC (decl) && !DECL_EXTERNAL (decl))
163 && flag_unit_at_a_time)
164 varpool_finalize_decl (decl);
165 else if (TREE_CODE (decl) == VAR_DECL && DECL_INITIAL (decl))
166 walk_tree (&DECL_INITIAL (decl), record_reference, node, visited_nodes);
169 pointer_set_destroy (visited_nodes);
170 initialize_inline_failed (node);
174 struct tree_opt_pass pass_build_cgraph_edges =
178 build_cgraph_edges, /* execute */
181 0, /* static_pass_number */
183 PROP_cfg, /* properties_required */
184 0, /* properties_provided */
185 0, /* properties_destroyed */
186 0, /* todo_flags_start */
187 0, /* todo_flags_finish */
191 /* Record references to functions and other variables present in the
192 initial value of DECL, a variable. */
195 record_references_in_initializer (tree decl)
197 struct pointer_set_t *visited_nodes = pointer_set_create ();
198 walk_tree (&DECL_INITIAL (decl), record_reference, NULL, visited_nodes);
199 pointer_set_destroy (visited_nodes);
202 /* Rebuild cgraph edges for current function node. This needs to be run after
203 passes that don't update the cgraph. */
206 rebuild_cgraph_edges (void)
209 struct cgraph_node *node = cgraph_node (current_function_decl);
210 block_stmt_iterator bsi;
211 int entry_freq = ENTRY_BLOCK_PTR->frequency;
216 cgraph_node_remove_callees (node);
218 node->count = ENTRY_BLOCK_PTR->count;
221 for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
223 tree stmt = bsi_stmt (bsi);
224 tree call = get_call_expr_in (stmt);
227 if (call && (decl = get_callee_fndecl (call)))
229 int freq = (!bb->frequency && !entry_freq ? CGRAPH_FREQ_BASE
230 : bb->frequency * CGRAPH_FREQ_BASE / entry_freq);
231 if (freq > CGRAPH_FREQ_MAX)
232 freq = CGRAPH_FREQ_MAX;
233 cgraph_create_edge (node, cgraph_node (decl), stmt,
234 bb->count, freq, bb->loop_depth);
237 initialize_inline_failed (node);
238 gcc_assert (!node->global.inlined_to);
242 struct tree_opt_pass pass_rebuild_cgraph_edges =
246 rebuild_cgraph_edges, /* execute */
249 0, /* static_pass_number */
251 PROP_cfg, /* properties_required */
252 0, /* properties_provided */
253 0, /* properties_destroyed */
254 0, /* todo_flags_start */
255 0, /* todo_flags_finish */