1/* Callgraph handling code.
2   Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
3   Contributed by Jan Hubicka
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 2, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING.  If not, write to the Free
19Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
2002110-1301, USA.  */
21
22#ifndef GCC_CGRAPH_H
23#define GCC_CGRAPH_H
24#include "tree.h"
25#include "basic-block.h"
26
27enum availability
28{
29  /* Not yet set by cgraph_function_body_availability.  */
30  AVAIL_UNSET,
31  /* Function body/variable initializer is unknown.  */
32  AVAIL_NOT_AVAILABLE,
33  /* Function body/variable initializer is known but might be replaced
34     by a different one from other compilation unit and thus needs to
35     be dealt with a care.  Like AVAIL_NOT_AVAILABLE it can have
36     arbitrary side effects on escaping variables and functions, while
37     like AVAILABLE it might access static variables.  */
38  AVAIL_OVERWRITABLE,
39  /* Function body/variable initializer is known and will be used in final
40     program.  */
41  AVAIL_AVAILABLE,
42  /* Function body/variable initializer is known and all it's uses are explicitly
43     visible within current unit (ie it's address is never taken and it is not
44     exported to other units).
45     Currently used only for functions.  */
46  AVAIL_LOCAL
47};
48
49/* Information about the function collected locally.
50   Available after function is analyzed.  */
51
52struct cgraph_local_info GTY(())
53{
54  /* Size of the function before inlining.  */
55  int self_insns;
56
57  /* Set when function function is visible in current compilation unit only
58     and its address is never taken.  */
59  bool local;
60
61  /* Set when function is visible by other units.  */
62  bool externally_visible;
63
64  /* Set once it has been finalized so we consider it to be output.  */
65  bool finalized;
66
67  /* False when there something makes inlining impossible (such as va_arg).  */
68  bool inlinable;
69
70  /* True when function should be inlined independently on its size.  */
71  bool disregard_inline_limits;
72
73  /* True when the function has been originally extern inline, but it is
74     redefined now.  */
75  bool redefined_extern_inline;
76
77  /* True if statics_read_for_function and
78     statics_written_for_function contain valid data.  */
79  bool for_functions_valid;
80
81  /* True if the function is going to be emitted in some other translation
82     unit, referenced from vtable.  */
83  bool vtable_method;
84};
85
86/* Information about the function that needs to be computed globally
87   once compilation is finished.  Available only with -funit-at-time.  */
88
89struct cgraph_global_info GTY(())
90{
91  /* For inline clones this points to the function they will be inlined into.  */
92  struct cgraph_node *inlined_to;
93
94  /* Estimated size of the function after inlining.  */
95  int insns;
96
97  /* Estimated growth after inlining.  INT_MIN if not computed.  */
98  int estimated_growth;
99
100  /* Set iff the function has been inlined at least once.  */
101  bool inlined;
102};
103
104/* Information about the function that is propagated by the RTL backend.
105   Available only for functions that has been already assembled.  */
106
107struct cgraph_rtl_info GTY(())
108{
109   int preferred_incoming_stack_boundary;
110};
111
112/* The cgraph data structure.
113   Each function decl has assigned cgraph_node listing callees and callers.  */
114
115struct cgraph_node GTY((chain_next ("%h.next"), chain_prev ("%h.previous")))
116{
117  tree decl;
118  struct cgraph_edge *callees;
119  struct cgraph_edge *callers;
120  struct cgraph_node *next;
121  struct cgraph_node *previous;
122  /* For nested functions points to function the node is nested in.  */
123  struct cgraph_node *origin;
124  /* Points to first nested function, if any.  */
125  struct cgraph_node *nested;
126  /* Pointer to the next function with same origin, if any.  */
127  struct cgraph_node *next_nested;
128  /* Pointer to the next function in cgraph_nodes_queue.  */
129  struct cgraph_node *next_needed;
130  /* Pointer to the next clone.  */
131  struct cgraph_node *next_clone;
132  struct cgraph_node *prev_clone;
133  /* Pointer to a single unique cgraph node for this function.  If the
134     function is to be output, this is the copy that will survive.  */
135  struct cgraph_node *master_clone;
136
137  PTR GTY ((skip)) aux;
138
139  struct cgraph_local_info local;
140  struct cgraph_global_info global;
141  struct cgraph_rtl_info rtl;
142
143  /* Expected number of executions: calculated in profile.c.  */
144  gcov_type count;
145  /* Unique id of the node.  */
146  int uid;
147  /* Set when function must be output - it is externally visible
148     or its address is taken.  */
149  bool needed;
150  /* Set when function is reachable by call from other function
151     that is either reachable or needed.  */
152  bool reachable;
153  /* Set once the function is lowered (ie it's CFG is built).  */
154  bool lowered;
155  /* Set once the function has been instantiated and its callee
156     lists created.  */
157  bool analyzed;
158  /* Set when function is scheduled to be assembled.  */
159  bool output;
160  /* Set when function is visible by other units.  */
161  bool externally_visible;
162  /* Set for aliases once they got through assemble_alias.  */
163  bool alias;
164};
165
166struct cgraph_edge GTY((chain_next ("%h.next_caller"), chain_prev ("%h.prev_caller")))
167{
168  struct cgraph_node *caller;
169  struct cgraph_node *callee;
170  struct cgraph_edge *prev_caller;
171  struct cgraph_edge *next_caller;
172  struct cgraph_edge *prev_callee;
173  struct cgraph_edge *next_callee;
174  tree call_stmt;
175  PTR GTY ((skip (""))) aux;
176  /* When NULL, inline this call.  When non-NULL, points to the explanation
177     why function was not inlined.  */
178  const char *inline_failed;
179  /* Expected number of executions: calculated in profile.c.  */
180  gcov_type count;
181  /* Depth of loop nest, 1 means no loop nest.  */
182  int loop_nest;
183};
184
185/* The cgraph_varpool data structure.
186   Each static variable decl has assigned cgraph_varpool_node.  */
187
188struct cgraph_varpool_node GTY(())
189{
190  tree decl;
191  /* Pointer to the next function in cgraph_varpool_nodes.  */
192  struct cgraph_varpool_node *next;
193  /* Pointer to the next function in cgraph_varpool_nodes_queue.  */
194  struct cgraph_varpool_node *next_needed;
195
196  /* Set when function must be output - it is externally visible
197     or its address is taken.  */
198  bool needed;
199  /* Needed variables might become dead by optimization.  This flag
200     forces the variable to be output even if it appears dead otherwise.  */
201  bool force_output;
202  /* Set once the variable has been instantiated and its callee
203     lists created.  */
204  bool analyzed;
205  /* Set once it has been finalized so we consider it to be output.  */
206  bool finalized;
207  /* Set when variable is scheduled to be assembled.  */
208  bool output;
209  /* Set when function is visible by other units.  */
210  bool externally_visible;
211  /* Set for aliases once they got through assemble_alias.  */
212  bool alias;
213};
214
215extern GTY(()) struct cgraph_node *cgraph_nodes;
216extern GTY(()) int cgraph_n_nodes;
217extern GTY(()) int cgraph_max_uid;
218extern bool cgraph_global_info_ready;
219extern bool cgraph_function_flags_ready;
220extern GTY(()) struct cgraph_node *cgraph_nodes_queue;
221
222extern GTY(()) struct cgraph_varpool_node *cgraph_varpool_first_unanalyzed_node;
223extern GTY(()) struct cgraph_varpool_node *cgraph_varpool_nodes_queue;
224extern GTY(()) struct cgraph_varpool_node *cgraph_varpool_nodes;
225
226/* In cgraph.c  */
227void dump_cgraph (FILE *);
228void dump_cgraph_node (FILE *, struct cgraph_node *);
229void dump_varpool (FILE *);
230void dump_cgraph_varpool_node (FILE *, struct cgraph_varpool_node *);
231void cgraph_remove_edge (struct cgraph_edge *);
232void cgraph_remove_node (struct cgraph_node *);
233void cgraph_node_remove_callees (struct cgraph_node *node);
234struct cgraph_edge *cgraph_create_edge (struct cgraph_node *,
235					struct cgraph_node *,
236				        tree, gcov_type, int);
237struct cgraph_node *cgraph_node (tree);
238struct cgraph_node *cgraph_node_for_asm (tree asmname);
239struct cgraph_edge *cgraph_edge (struct cgraph_node *, tree);
240struct cgraph_local_info *cgraph_local_info (tree);
241struct cgraph_global_info *cgraph_global_info (tree);
242struct cgraph_rtl_info *cgraph_rtl_info (tree);
243const char * cgraph_node_name (struct cgraph_node *);
244struct cgraph_edge * cgraph_clone_edge (struct cgraph_edge *,
245				        struct cgraph_node *,
246				        tree, gcov_type, int, bool);
247struct cgraph_node * cgraph_clone_node (struct cgraph_node *, gcov_type,
248					int, bool);
249
250struct cgraph_varpool_node *cgraph_varpool_node (tree);
251struct cgraph_varpool_node *cgraph_varpool_node_for_asm (tree asmname);
252void cgraph_varpool_mark_needed_node (struct cgraph_varpool_node *);
253void cgraph_varpool_finalize_decl (tree);
254void cgraph_redirect_edge_callee (struct cgraph_edge *, struct cgraph_node *);
255
256bool cgraph_function_possibly_inlined_p (tree);
257void cgraph_unnest_node (struct cgraph_node *);
258void cgraph_varpool_enqueue_needed_node (struct cgraph_varpool_node *);
259void cgraph_varpool_reset_queue (void);
260bool decide_is_variable_needed (struct cgraph_varpool_node *, tree);
261
262enum availability cgraph_function_body_availability (struct cgraph_node *);
263enum availability cgraph_variable_initializer_availability (struct cgraph_varpool_node *);
264bool cgraph_is_master_clone (struct cgraph_node *);
265struct cgraph_node *cgraph_master_clone (struct cgraph_node *);
266
267/* In cgraphunit.c  */
268bool cgraph_assemble_pending_functions (void);
269bool cgraph_varpool_assemble_pending_decls (void);
270void cgraph_finalize_function (tree, bool);
271void cgraph_lower_function (struct cgraph_node *);
272void cgraph_finalize_compilation_unit (void);
273void cgraph_optimize (void);
274void cgraph_mark_needed_node (struct cgraph_node *);
275void cgraph_mark_reachable_node (struct cgraph_node *);
276bool cgraph_inline_p (struct cgraph_edge *, const char **reason);
277bool cgraph_preserve_function_body_p (tree);
278void verify_cgraph (void);
279void verify_cgraph_node (struct cgraph_node *);
280void cgraph_build_static_cdtor (char which, tree body, int priority);
281void cgraph_reset_static_var_maps (void);
282void init_cgraph (void);
283struct cgraph_node *cgraph_function_versioning (struct cgraph_node *,
284                                                varray_type, varray_type);
285
286/* In ipa.c  */
287bool cgraph_remove_unreachable_nodes (bool, FILE *);
288int cgraph_postorder (struct cgraph_node **);
289
290/* In ipa-inline.c  */
291bool cgraph_decide_inlining_incrementally (struct cgraph_node *, bool);
292void cgraph_clone_inlined_nodes (struct cgraph_edge *, bool, bool);
293void cgraph_mark_inline_edge (struct cgraph_edge *, bool);
294bool cgraph_default_inline_p (struct cgraph_node *, const char **);
295#endif  /* GCC_CGRAPH_H  */
296