xref: /openbsd/gnu/gcc/gcc/cgraph.h (revision 404b540a)
1 /* Callgraph handling code.
2    Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
3    Contributed by Jan Hubicka
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 2, 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 COPYING.  If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
20 02110-1301, USA.  */
21 
22 #ifndef GCC_CGRAPH_H
23 #define GCC_CGRAPH_H
24 #include "tree.h"
25 #include "basic-block.h"
26 
27 enum 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 
52 struct 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   unsigned local : 1;
60 
61   /* Set when function is visible by other units.  */
62   unsigned externally_visible : 1;
63 
64   /* Set once it has been finalized so we consider it to be output.  */
65   unsigned finalized : 1;
66 
67   /* False when there something makes inlining impossible (such as va_arg).  */
68   unsigned inlinable : 1;
69 
70   /* True when function should be inlined independently on its size.  */
71   unsigned disregard_inline_limits : 1;
72 
73   /* True when the function has been originally extern inline, but it is
74      redefined now.  */
75   unsigned redefined_extern_inline : 1;
76 
77   /* True if statics_read_for_function and
78      statics_written_for_function contain valid data.  */
79   unsigned for_functions_valid : 1;
80 
81   /* True if the function is going to be emitted in some other translation
82      unit, referenced from vtable.  */
83   unsigned vtable_method : 1;
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 
89 struct 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 
107 struct 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 
115 struct 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   /* For functions with many calls sites it holds map from call expression
137      to the edge to speed up cgraph_edge function.  */
138   htab_t GTY((param_is (struct cgraph_edge))) call_site_hash;
139 
140   PTR GTY ((skip)) aux;
141 
142   struct cgraph_local_info local;
143   struct cgraph_global_info global;
144   struct cgraph_rtl_info rtl;
145 
146   /* Expected number of executions: calculated in profile.c.  */
147   gcov_type count;
148   /* Unique id of the node.  */
149   int uid;
150   /* Ordering of all cgraph nodes.  */
151   int order;
152 
153   /* Set when function must be output - it is externally visible
154      or its address is taken.  */
155   unsigned needed : 1;
156   /* Set when function is reachable by call from other function
157      that is either reachable or needed.  */
158   unsigned reachable : 1;
159   /* Set once the function is lowered (i.e. its CFG is built).  */
160   unsigned lowered : 1;
161   /* Set once the function has been instantiated and its callee
162      lists created.  */
163   unsigned analyzed : 1;
164   /* Set when function is scheduled to be assembled.  */
165   unsigned output : 1;
166   /* Set for aliases once they got through assemble_alias.  */
167   unsigned alias : 1;
168 
169   /* In non-unit-at-a-time mode the function body of inline candidates is saved
170      into clone before compiling so the function in original form can be
171      inlined later.  This pointer points to the clone.  */
172   tree inline_decl;
173 };
174 
175 struct cgraph_edge GTY((chain_next ("%h.next_caller"), chain_prev ("%h.prev_caller")))
176 {
177   struct cgraph_node *caller;
178   struct cgraph_node *callee;
179   struct cgraph_edge *prev_caller;
180   struct cgraph_edge *next_caller;
181   struct cgraph_edge *prev_callee;
182   struct cgraph_edge *next_callee;
183   tree call_stmt;
184   PTR GTY ((skip (""))) aux;
185   /* When NULL, inline this call.  When non-NULL, points to the explanation
186      why function was not inlined.  */
187   const char *inline_failed;
188   /* Expected number of executions: calculated in profile.c.  */
189   gcov_type count;
190   /* Depth of loop nest, 1 means no loop nest.  */
191   int loop_nest;
192 };
193 
194 typedef struct cgraph_edge *cgraph_edge_p;
195 
196 DEF_VEC_P(cgraph_edge_p);
197 DEF_VEC_ALLOC_P(cgraph_edge_p,heap);
198 
199 /* The cgraph_varpool data structure.
200    Each static variable decl has assigned cgraph_varpool_node.  */
201 
202 struct cgraph_varpool_node GTY(())
203 {
204   tree decl;
205   /* Pointer to the next function in cgraph_varpool_nodes.  */
206   struct cgraph_varpool_node *next;
207   /* Pointer to the next function in cgraph_varpool_nodes_queue.  */
208   struct cgraph_varpool_node *next_needed;
209   /* Ordering of all cgraph nodes.  */
210   int order;
211 
212   /* Set when function must be output - it is externally visible
213      or its address is taken.  */
214   unsigned needed : 1;
215   /* Needed variables might become dead by optimization.  This flag
216      forces the variable to be output even if it appears dead otherwise.  */
217   unsigned force_output : 1;
218   /* Set once the variable has been instantiated and its callee
219      lists created.  */
220   unsigned analyzed : 1;
221   /* Set once it has been finalized so we consider it to be output.  */
222   unsigned finalized : 1;
223   /* Set when variable is scheduled to be assembled.  */
224   unsigned output : 1;
225   /* Set when function is visible by other units.  */
226   unsigned externally_visible : 1;
227   /* Set for aliases once they got through assemble_alias.  */
228   unsigned alias : 1;
229 };
230 
231 /* Every top level asm statement is put into a cgraph_asm_node.  */
232 
233 struct cgraph_asm_node GTY(())
234 {
235   /* Next asm node.  */
236   struct cgraph_asm_node *next;
237   /* String for this asm node.  */
238   tree asm_str;
239   /* Ordering of all cgraph nodes.  */
240   int order;
241 };
242 
243 extern GTY(()) struct cgraph_node *cgraph_nodes;
244 extern GTY(()) int cgraph_n_nodes;
245 extern GTY(()) int cgraph_max_uid;
246 extern bool cgraph_global_info_ready;
247 extern bool cgraph_function_flags_ready;
248 extern GTY(()) struct cgraph_node *cgraph_nodes_queue;
249 extern GTY(()) struct cgraph_node *cgraph_expand_queue;
250 
251 extern GTY(()) struct cgraph_varpool_node *cgraph_varpool_first_unanalyzed_node;
252 extern GTY(()) struct cgraph_varpool_node *cgraph_varpool_last_needed_node;
253 extern GTY(()) struct cgraph_varpool_node *cgraph_varpool_nodes_queue;
254 extern GTY(()) struct cgraph_varpool_node *cgraph_varpool_nodes;
255 extern GTY(()) struct cgraph_asm_node *cgraph_asm_nodes;
256 extern GTY(()) int cgraph_order;
257 
258 /* In cgraph.c  */
259 void dump_cgraph (FILE *);
260 void dump_cgraph_node (FILE *, struct cgraph_node *);
261 void cgraph_insert_node_to_hashtable (struct cgraph_node *node);
262 void dump_varpool (FILE *);
263 void dump_cgraph_varpool_node (FILE *, struct cgraph_varpool_node *);
264 void cgraph_remove_edge (struct cgraph_edge *);
265 void cgraph_remove_node (struct cgraph_node *);
266 void cgraph_node_remove_callees (struct cgraph_node *node);
267 struct cgraph_edge *cgraph_create_edge (struct cgraph_node *,
268 					struct cgraph_node *,
269 					tree, gcov_type, int);
270 struct cgraph_node *cgraph_node (tree);
271 struct cgraph_node *cgraph_node_for_asm (tree asmname);
272 struct cgraph_edge *cgraph_edge (struct cgraph_node *, tree);
273 void cgraph_set_call_stmt (struct cgraph_edge *, tree);
274 struct cgraph_local_info *cgraph_local_info (tree);
275 struct cgraph_global_info *cgraph_global_info (tree);
276 struct cgraph_rtl_info *cgraph_rtl_info (tree);
277 const char * cgraph_node_name (struct cgraph_node *);
278 struct cgraph_edge * cgraph_clone_edge (struct cgraph_edge *,
279 					struct cgraph_node *,
280 					tree, gcov_type, int, bool);
281 struct cgraph_node * cgraph_clone_node (struct cgraph_node *, gcov_type,
282 					int, bool);
283 
284 struct cgraph_varpool_node *cgraph_varpool_node (tree);
285 struct cgraph_varpool_node *cgraph_varpool_node_for_asm (tree asmname);
286 void cgraph_varpool_mark_needed_node (struct cgraph_varpool_node *);
287 void cgraph_varpool_finalize_decl (tree);
288 void cgraph_redirect_edge_callee (struct cgraph_edge *, struct cgraph_node *);
289 
290 struct cgraph_asm_node *cgraph_add_asm_node (tree);
291 
292 bool cgraph_function_possibly_inlined_p (tree);
293 void cgraph_unnest_node (struct cgraph_node *);
294 void cgraph_varpool_enqueue_needed_node (struct cgraph_varpool_node *);
295 void cgraph_varpool_reset_queue (void);
296 bool decide_is_variable_needed (struct cgraph_varpool_node *, tree);
297 
298 enum availability cgraph_function_body_availability (struct cgraph_node *);
299 enum availability cgraph_variable_initializer_availability (struct cgraph_varpool_node *);
300 bool cgraph_is_master_clone (struct cgraph_node *);
301 struct cgraph_node *cgraph_master_clone (struct cgraph_node *);
302 void cgraph_add_new_function (tree);
303 
304 /* In cgraphunit.c  */
305 bool cgraph_assemble_pending_functions (void);
306 bool cgraph_varpool_assemble_pending_decls (void);
307 void cgraph_finalize_function (tree, bool);
308 void cgraph_finalize_compilation_unit (void);
309 void cgraph_optimize (void);
310 void cgraph_mark_needed_node (struct cgraph_node *);
311 void cgraph_mark_reachable_node (struct cgraph_node *);
312 bool cgraph_inline_p (struct cgraph_edge *, const char **reason);
313 bool cgraph_preserve_function_body_p (tree);
314 void verify_cgraph (void);
315 void verify_cgraph_node (struct cgraph_node *);
316 void cgraph_build_static_cdtor (char which, tree body, int priority);
317 void cgraph_reset_static_var_maps (void);
318 void init_cgraph (void);
319 struct cgraph_node *cgraph_function_versioning (struct cgraph_node *,
320 						VEC(cgraph_edge_p,heap)*,
321 						varray_type);
322 void cgraph_analyze_function (struct cgraph_node *);
323 struct cgraph_node *save_inline_function_body (struct cgraph_node *);
324 
325 /* In ipa.c  */
326 bool cgraph_remove_unreachable_nodes (bool, FILE *);
327 int cgraph_postorder (struct cgraph_node **);
328 
329 /* In ipa-inline.c  */
330 bool cgraph_decide_inlining_incrementally (struct cgraph_node *, bool);
331 void cgraph_clone_inlined_nodes (struct cgraph_edge *, bool, bool);
332 void cgraph_mark_inline_edge (struct cgraph_edge *, bool);
333 bool cgraph_default_inline_p (struct cgraph_node *, const char **);
334 #endif  /* GCC_CGRAPH_H  */
335