Mercurial > hg > CbC > CbC_gcc

comparison gcc/ipa.c @ 0:a06113de4d67

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
first commit
author kent <kent@cr.ie.u-ryukyu.ac.jp>
date Fri, 17 Jul 2009 14:47:48 +0900
parents
children 77e2b8dfacca
comparison
equal deleted inserted replaced
-1:000000000000 0:a06113de4d67
1 /* Basic IPA optimizations and utilities.
2 Copyright (C) 2003, 2004, 2005, 2007, 2008 Free Software Foundation,
3 Inc.
4
5 This file is part of GCC.
6
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
10 version.
11
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
15 for more details.
16
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/>. */
20
21 #include "config.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "tm.h"
25 #include "cgraph.h"
26 #include "tree-pass.h"
27 #include "timevar.h"
28
29 /* Fill array order with all nodes with output flag set in the reverse
30 topological order. */
31
32 int
33 cgraph_postorder (struct cgraph_node **order)
34 {
35 struct cgraph_node *node, *node2;
36 int stack_size = 0;
37 int order_pos = 0;
38 struct cgraph_edge *edge, last;
39
40 struct cgraph_node **stack =
41 XCNEWVEC (struct cgraph_node *, cgraph_n_nodes);
42
43 /* We have to deal with cycles nicely, so use a depth first traversal
44 output algorithm. Ignore the fact that some functions won't need
45 to be output and put them into order as well, so we get dependencies
46 right through inline functions. */
47 for (node = cgraph_nodes; node; node = node->next)
48 node->aux = NULL;
49 for (node = cgraph_nodes; node; node = node->next)
50 if (!node->aux)
51 {
52 node2 = node;
53 if (!node->callers)
54 node->aux = &last;
55 else
56 node->aux = node->callers;
57 while (node2)
58 {
59 while (node2->aux != &last)
60 {
61 edge = (struct cgraph_edge *) node2->aux;
62 if (edge->next_caller)
63 node2->aux = edge->next_caller;
64 else
65 node2->aux = &last;
66 if (!edge->caller->aux)
67 {
68 if (!edge->caller->callers)
69 edge->caller->aux = &last;
70 else
71 edge->caller->aux = edge->caller->callers;
72 stack[stack_size++] = node2;
73 node2 = edge->caller;
74 break;
75 }
76 }
77 if (node2->aux == &last)
78 {
79 order[order_pos++] = node2;
80 if (stack_size)
81 node2 = stack[--stack_size];
82 else
83 node2 = NULL;
84 }
85 }
86 }
87 free (stack);
88 for (node = cgraph_nodes; node; node = node->next)
89 node->aux = NULL;
90 return order_pos;
91 }
92
93 /* Perform reachability analysis and reclaim all unreachable nodes.
94 If BEFORE_INLINING_P is true this function is called before inlining
95 decisions has been made. If BEFORE_INLINING_P is false this function also
96 removes unneeded bodies of extern inline functions. */
97
98 bool
99 cgraph_remove_unreachable_nodes (bool before_inlining_p, FILE *file)
100 {
101 struct cgraph_node *first = (struct cgraph_node *) (void *) 1;
102 struct cgraph_node *node, *next;
103 bool changed = false;
104
105 #ifdef ENABLE_CHECKING
106 verify_cgraph ();
107 #endif
108 if (file)
109 fprintf (file, "\nReclaiming functions:");
110 #ifdef ENABLE_CHECKING
111 for (node = cgraph_nodes; node; node = node->next)
112 gcc_assert (!node->aux);
113 #endif
114 for (node = cgraph_nodes; node; node = node->next)
115 if (node->needed && !node->global.inlined_to
116 && ((!DECL_EXTERNAL (node->decl))
117 || !node->analyzed
118 || before_inlining_p))
119 {
120 node->aux = first;
121 first = node;
122 }
123 else
124 gcc_assert (!node->aux);
125
126 /* Perform reachability analysis. As a special case do not consider
127 extern inline functions not inlined as live because we won't output
128 them at all. */
129 while (first != (void *) 1)
130 {
131 struct cgraph_edge *e;
132 node = first;
133 first = (struct cgraph_node *) first->aux;
134
135 for (e = node->callees; e; e = e->next_callee)
136 if (!e->callee->aux
137 && node->analyzed
138 && (!e->inline_failed || !e->callee->analyzed
139 || (!DECL_EXTERNAL (e->callee->decl))
140 || before_inlining_p))
141 {
142 e->callee->aux = first;
143 first = e->callee;
144 }
145 }
146
147 /* Remove unreachable nodes. Extern inline functions need special care;
148 Unreachable extern inline functions shall be removed.
149 Reachable extern inline functions we never inlined shall get their bodies
150 eliminated.
151 Reachable extern inline functions we sometimes inlined will be turned into
152 unanalyzed nodes so they look like for true extern functions to the rest
153 of code. Body of such functions is released via remove_node once the
154 inline clones are eliminated. */
155 for (node = cgraph_nodes; node; node = next)
156 {
157 next = node->next;
158 if (!node->aux)
159 {
160 node->global.inlined_to = NULL;
161 if (file)
162 fprintf (file, " %s", cgraph_node_name (node));
163 if (!node->analyzed || !DECL_EXTERNAL (node->decl)
164 || before_inlining_p)
165 cgraph_remove_node (node);
166 else
167 {
168 struct cgraph_edge *e;
169
170 for (e = node->callers; e; e = e->next_caller)
171 if (e->caller->aux)
172 break;
173 if (e || node->needed)
174 {
175 struct cgraph_node *clone;
176
177 for (clone = node->next_clone; clone;
178 clone = clone->next_clone)
179 if (clone->aux)
180 break;
181 if (!clone)
182 {
183 cgraph_release_function_body (node);
184 node->analyzed = false;
185 }
186 cgraph_node_remove_callees (node);
187 node->analyzed = false;
188 node->local.inlinable = false;
189 }
190 else
191 cgraph_remove_node (node);
192 }
193 changed = true;
194 }
195 }
196 for (node = cgraph_nodes; node; node = node->next)
197 node->aux = NULL;
198 #ifdef ENABLE_CHECKING
199 verify_cgraph ();
200 #endif
201 return changed;
202 }
203
204 /* Mark visibility of all functions.
205
206 A local function is one whose calls can occur only in the current
207 compilation unit and all its calls are explicit, so we can change
208 its calling convention. We simply mark all static functions whose
209 address is not taken as local.
210
211 We also change the TREE_PUBLIC flag of all declarations that are public
212 in language point of view but we want to overwrite this default
213 via visibilities for the backend point of view. */
214
215 static unsigned int
216 function_and_variable_visibility (void)
217 {
218 struct cgraph_node *node;
219 struct varpool_node *vnode;
220
221 for (node = cgraph_nodes; node; node = node->next)
222 {
223 if (node->reachable
224 && (DECL_COMDAT (node->decl)
225 || (!flag_whole_program
226 && TREE_PUBLIC (node->decl) && !DECL_EXTERNAL (node->decl))))
227 node->local.externally_visible = true;
228 if (!node->local.externally_visible && node->analyzed
229 && !DECL_EXTERNAL (node->decl))
230 {
231 gcc_assert (flag_whole_program || !TREE_PUBLIC (node->decl));
232 TREE_PUBLIC (node->decl) = 0;
233 }
234 node->local.local = (!node->needed
235 && node->analyzed
236 && !DECL_EXTERNAL (node->decl)
237 && !node->local.externally_visible);
238 }
239 for (vnode = varpool_nodes_queue; vnode; vnode = vnode->next_needed)
240 {
241 if (vnode->needed
242 && !flag_whole_program
243 && (DECL_COMDAT (vnode->decl) || TREE_PUBLIC (vnode->decl)))
244 vnode->externally_visible = 1;
245 if (!vnode->externally_visible)
246 {
247 gcc_assert (flag_whole_program || !TREE_PUBLIC (vnode->decl));
248 TREE_PUBLIC (vnode->decl) = 0;
249 }
250 gcc_assert (TREE_STATIC (vnode->decl));
251 }
252
253 if (dump_file)
254 {
255 fprintf (dump_file, "\nMarking local functions:");
256 for (node = cgraph_nodes; node; node = node->next)
257 if (node->local.local)
258 fprintf (dump_file, " %s", cgraph_node_name (node));
259 fprintf (dump_file, "\n\n");
260 fprintf (dump_file, "\nMarking externally visible functions:");
261 for (node = cgraph_nodes; node; node = node->next)
262 if (node->local.externally_visible)
263 fprintf (dump_file, " %s", cgraph_node_name (node));
264 fprintf (dump_file, "\n\n");
265 }
266 cgraph_function_flags_ready = true;
267 return 0;
268 }
269
270 struct simple_ipa_opt_pass pass_ipa_function_and_variable_visibility =
271 {
272 {
273 SIMPLE_IPA_PASS,
274 "visibility", /* name */
275 NULL, /* gate */
276 function_and_variable_visibility, /* execute */
277 NULL, /* sub */
278 NULL, /* next */
279 0, /* static_pass_number */
280 TV_CGRAPHOPT, /* tv_id */
281 0, /* properties_required */
282 0, /* properties_provided */
283 0, /* properties_destroyed */
284 0, /* todo_flags_start */
285 TODO_remove_functions | TODO_dump_cgraph/* todo_flags_finish */
286 }
287 };