xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/cgraph.c (revision d536862b7d93d77932ef5de7eebdc48d76921b77)
1 /* Callgraph handling code.
2    Copyright (C) 2003-2019 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 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 /*  This file contains basic routines manipulating call graph
22 
23     The call-graph is a data structure designed for inter-procedural
24     optimization.  It represents a multi-graph where nodes are functions
25     (symbols within symbol table) and edges are call sites. */
26 
27 #include "config.h"
28 #include "system.h"
29 #include "coretypes.h"
30 #include "backend.h"
31 #include "target.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "gimple.h"
35 #include "predict.h"
36 #include "alloc-pool.h"
37 #include "gimple-ssa.h"
38 #include "cgraph.h"
39 #include "lto-streamer.h"
40 #include "fold-const.h"
41 #include "varasm.h"
42 #include "calls.h"
43 #include "print-tree.h"
44 #include "langhooks.h"
45 #include "intl.h"
46 #include "tree-eh.h"
47 #include "gimple-iterator.h"
48 #include "tree-cfg.h"
49 #include "tree-ssa.h"
50 #include "value-prof.h"
51 #include "ipa-utils.h"
52 #include "symbol-summary.h"
53 #include "tree-vrp.h"
54 #include "ipa-prop.h"
55 #include "ipa-fnsummary.h"
56 #include "cfgloop.h"
57 #include "gimple-pretty-print.h"
58 #include "tree-dfa.h"
59 #include "profile.h"
60 #include "params.h"
61 #include "context.h"
62 #include "gimplify.h"
63 #include "stringpool.h"
64 #include "attribs.h"
65 #include "selftest.h"
66 
67 /* FIXME: Only for PROP_loops, but cgraph shouldn't have to know about this.  */
68 #include "tree-pass.h"
69 
70 /* Queue of cgraph nodes scheduled to be lowered.  */
71 symtab_node *x_cgraph_nodes_queue;
72 #define cgraph_nodes_queue ((cgraph_node *)x_cgraph_nodes_queue)
73 
74 /* Symbol table global context.  */
75 symbol_table *symtab;
76 
77 /* List of hooks triggered on cgraph_edge events.  */
78 struct cgraph_edge_hook_list {
79   cgraph_edge_hook hook;
80   void *data;
81   struct cgraph_edge_hook_list *next;
82 };
83 
84 /* List of hooks triggered on cgraph_node events.  */
85 struct cgraph_node_hook_list {
86   cgraph_node_hook hook;
87   void *data;
88   struct cgraph_node_hook_list *next;
89 };
90 
91 /* List of hooks triggered on events involving two cgraph_edges.  */
92 struct cgraph_2edge_hook_list {
93   cgraph_2edge_hook hook;
94   void *data;
95   struct cgraph_2edge_hook_list *next;
96 };
97 
98 /* List of hooks triggered on events involving two cgraph_nodes.  */
99 struct cgraph_2node_hook_list {
100   cgraph_2node_hook hook;
101   void *data;
102   struct cgraph_2node_hook_list *next;
103 };
104 
105 /* Hash descriptor for cgraph_function_version_info.  */
106 
107 struct function_version_hasher : ggc_ptr_hash<cgraph_function_version_info>
108 {
109   static hashval_t hash (cgraph_function_version_info *);
110   static bool equal (cgraph_function_version_info *,
111 		     cgraph_function_version_info *);
112 };
113 
114 /* Map a cgraph_node to cgraph_function_version_info using this htab.
115    The cgraph_function_version_info has a THIS_NODE field that is the
116    corresponding cgraph_node..  */
117 
118 static GTY(()) hash_table<function_version_hasher> *cgraph_fnver_htab = NULL;
119 
120 /* Hash function for cgraph_fnver_htab.  */
121 hashval_t
122 function_version_hasher::hash (cgraph_function_version_info *ptr)
123 {
124   int uid = ptr->this_node->get_uid ();
125   return (hashval_t)(uid);
126 }
127 
128 /* eq function for cgraph_fnver_htab.  */
129 bool
130 function_version_hasher::equal (cgraph_function_version_info *n1,
131 			       	cgraph_function_version_info *n2)
132 {
133   return n1->this_node->get_uid () == n2->this_node->get_uid ();
134 }
135 
136 /* Mark as GC root all allocated nodes.  */
137 static GTY(()) struct cgraph_function_version_info *
138   version_info_node = NULL;
139 
140 /* Return true if NODE's address can be compared.  */
141 
142 bool
143 symtab_node::address_can_be_compared_p ()
144 {
145   /* Address of virtual tables and functions is never compared.  */
146   if (DECL_VIRTUAL_P (decl))
147     return false;
148   /* Address of C++ cdtors is never compared.  */
149   if (is_a <cgraph_node *> (this)
150       && (DECL_CXX_CONSTRUCTOR_P (decl)
151 	  || DECL_CXX_DESTRUCTOR_P (decl)))
152     return false;
153   /* Constant pool symbols addresses are never compared.
154      flag_merge_constants permits us to assume the same on readonly vars.  */
155   if (is_a <varpool_node *> (this)
156       && (DECL_IN_CONSTANT_POOL (decl)
157 	  || (flag_merge_constants >= 2
158 	      && TREE_READONLY (decl) && !TREE_THIS_VOLATILE (decl))))
159     return false;
160   return true;
161 }
162 
163 /* Get the cgraph_function_version_info node corresponding to node.  */
164 cgraph_function_version_info *
165 cgraph_node::function_version (void)
166 {
167   cgraph_function_version_info key;
168   key.this_node = this;
169 
170   if (cgraph_fnver_htab == NULL)
171     return NULL;
172 
173   return cgraph_fnver_htab->find (&key);
174 }
175 
176 /* Insert a new cgraph_function_version_info node into cgraph_fnver_htab
177    corresponding to cgraph_node NODE.  */
178 cgraph_function_version_info *
179 cgraph_node::insert_new_function_version (void)
180 {
181   version_info_node = NULL;
182   version_info_node = ggc_cleared_alloc<cgraph_function_version_info> ();
183   version_info_node->this_node = this;
184 
185   if (cgraph_fnver_htab == NULL)
186     cgraph_fnver_htab = hash_table<function_version_hasher>::create_ggc (2);
187 
188   *cgraph_fnver_htab->find_slot (version_info_node, INSERT)
189     = version_info_node;
190   return version_info_node;
191 }
192 
193 /* Remove the cgraph_function_version_info node given by DECL_V.  */
194 static void
195 delete_function_version (cgraph_function_version_info *decl_v)
196 {
197   if (decl_v == NULL)
198     return;
199 
200   if (decl_v->prev != NULL)
201     decl_v->prev->next = decl_v->next;
202 
203   if (decl_v->next != NULL)
204     decl_v->next->prev = decl_v->prev;
205 
206   if (cgraph_fnver_htab != NULL)
207     cgraph_fnver_htab->remove_elt (decl_v);
208 }
209 
210 /* Remove the cgraph_function_version_info and cgraph_node for DECL.  This
211    DECL is a duplicate declaration.  */
212 void
213 cgraph_node::delete_function_version_by_decl (tree decl)
214 {
215   cgraph_node *decl_node = cgraph_node::get (decl);
216 
217   if (decl_node == NULL)
218     return;
219 
220   delete_function_version (decl_node->function_version ());
221 
222   decl_node->remove ();
223 }
224 
225 /* Record that DECL1 and DECL2 are semantically identical function
226    versions.  */
227 void
228 cgraph_node::record_function_versions (tree decl1, tree decl2)
229 {
230   cgraph_node *decl1_node = cgraph_node::get_create (decl1);
231   cgraph_node *decl2_node = cgraph_node::get_create (decl2);
232   cgraph_function_version_info *decl1_v = NULL;
233   cgraph_function_version_info *decl2_v = NULL;
234   cgraph_function_version_info *before;
235   cgraph_function_version_info *after;
236 
237   gcc_assert (decl1_node != NULL && decl2_node != NULL);
238   decl1_v = decl1_node->function_version ();
239   decl2_v = decl2_node->function_version ();
240 
241   if (decl1_v != NULL && decl2_v != NULL)
242     return;
243 
244   if (decl1_v == NULL)
245     decl1_v = decl1_node->insert_new_function_version ();
246 
247   if (decl2_v == NULL)
248     decl2_v = decl2_node->insert_new_function_version ();
249 
250   /* Chain decl2_v and decl1_v.  All semantically identical versions
251      will be chained together.  */
252 
253   before = decl1_v;
254   after = decl2_v;
255 
256   while (before->next != NULL)
257     before = before->next;
258 
259   while (after->prev != NULL)
260     after= after->prev;
261 
262   before->next = after;
263   after->prev = before;
264 }
265 
266 /* Initialize callgraph dump file.  */
267 
268 void
269 symbol_table::initialize (void)
270 {
271   if (!dump_file)
272     dump_file = dump_begin (TDI_cgraph, NULL);
273 
274   if (!ipa_clones_dump_file)
275     ipa_clones_dump_file = dump_begin (TDI_clones, NULL);
276 }
277 
278 /* Allocate new callgraph node and insert it into basic data structures.  */
279 
280 cgraph_node *
281 symbol_table::create_empty (void)
282 {
283   cgraph_node *node = allocate_cgraph_symbol ();
284 
285   node->type = SYMTAB_FUNCTION;
286   node->frequency = NODE_FREQUENCY_NORMAL;
287   node->count_materialization_scale = REG_BR_PROB_BASE;
288   cgraph_count++;
289 
290   return node;
291 }
292 
293 /* Register HOOK to be called with DATA on each removed edge.  */
294 cgraph_edge_hook_list *
295 symbol_table::add_edge_removal_hook (cgraph_edge_hook hook, void *data)
296 {
297   cgraph_edge_hook_list *entry;
298   cgraph_edge_hook_list **ptr = &m_first_edge_removal_hook;
299 
300   entry = (cgraph_edge_hook_list *) xmalloc (sizeof (*entry));
301   entry->hook = hook;
302   entry->data = data;
303   entry->next = NULL;
304   while (*ptr)
305     ptr = &(*ptr)->next;
306   *ptr = entry;
307   return entry;
308 }
309 
310 /* Remove ENTRY from the list of hooks called on removing edges.  */
311 void
312 symbol_table::remove_edge_removal_hook (cgraph_edge_hook_list *entry)
313 {
314   cgraph_edge_hook_list **ptr = &m_first_edge_removal_hook;
315 
316   while (*ptr != entry)
317     ptr = &(*ptr)->next;
318   *ptr = entry->next;
319   free (entry);
320 }
321 
322 /* Call all edge removal hooks.  */
323 void
324 symbol_table::call_edge_removal_hooks (cgraph_edge *e)
325 {
326   cgraph_edge_hook_list *entry = m_first_edge_removal_hook;
327   while (entry)
328   {
329     entry->hook (e, entry->data);
330     entry = entry->next;
331   }
332 }
333 
334 /* Register HOOK to be called with DATA on each removed node.  */
335 cgraph_node_hook_list *
336 symbol_table::add_cgraph_removal_hook (cgraph_node_hook hook, void *data)
337 {
338   cgraph_node_hook_list *entry;
339   cgraph_node_hook_list **ptr = &m_first_cgraph_removal_hook;
340 
341   entry = (cgraph_node_hook_list *) xmalloc (sizeof (*entry));
342   entry->hook = hook;
343   entry->data = data;
344   entry->next = NULL;
345   while (*ptr)
346     ptr = &(*ptr)->next;
347   *ptr = entry;
348   return entry;
349 }
350 
351 /* Remove ENTRY from the list of hooks called on removing nodes.  */
352 void
353 symbol_table::remove_cgraph_removal_hook (cgraph_node_hook_list *entry)
354 {
355   cgraph_node_hook_list **ptr = &m_first_cgraph_removal_hook;
356 
357   while (*ptr != entry)
358     ptr = &(*ptr)->next;
359   *ptr = entry->next;
360   free (entry);
361 }
362 
363 /* Call all node removal hooks.  */
364 void
365 symbol_table::call_cgraph_removal_hooks (cgraph_node *node)
366 {
367   cgraph_node_hook_list *entry = m_first_cgraph_removal_hook;
368   while (entry)
369   {
370     entry->hook (node, entry->data);
371     entry = entry->next;
372   }
373 }
374 
375 /* Call all node removal hooks.  */
376 void
377 symbol_table::call_cgraph_insertion_hooks (cgraph_node *node)
378 {
379   cgraph_node_hook_list *entry = m_first_cgraph_insertion_hook;
380   while (entry)
381   {
382     entry->hook (node, entry->data);
383     entry = entry->next;
384   }
385 }
386 
387 
388 /* Register HOOK to be called with DATA on each inserted node.  */
389 cgraph_node_hook_list *
390 symbol_table::add_cgraph_insertion_hook (cgraph_node_hook hook, void *data)
391 {
392   cgraph_node_hook_list *entry;
393   cgraph_node_hook_list **ptr = &m_first_cgraph_insertion_hook;
394 
395   entry = (cgraph_node_hook_list *) xmalloc (sizeof (*entry));
396   entry->hook = hook;
397   entry->data = data;
398   entry->next = NULL;
399   while (*ptr)
400     ptr = &(*ptr)->next;
401   *ptr = entry;
402   return entry;
403 }
404 
405 /* Remove ENTRY from the list of hooks called on inserted nodes.  */
406 void
407 symbol_table::remove_cgraph_insertion_hook (cgraph_node_hook_list *entry)
408 {
409   cgraph_node_hook_list **ptr = &m_first_cgraph_insertion_hook;
410 
411   while (*ptr != entry)
412     ptr = &(*ptr)->next;
413   *ptr = entry->next;
414   free (entry);
415 }
416 
417 /* Register HOOK to be called with DATA on each duplicated edge.  */
418 cgraph_2edge_hook_list *
419 symbol_table::add_edge_duplication_hook (cgraph_2edge_hook hook, void *data)
420 {
421   cgraph_2edge_hook_list *entry;
422   cgraph_2edge_hook_list **ptr = &m_first_edge_duplicated_hook;
423 
424   entry = (cgraph_2edge_hook_list *) xmalloc (sizeof (*entry));
425   entry->hook = hook;
426   entry->data = data;
427   entry->next = NULL;
428   while (*ptr)
429     ptr = &(*ptr)->next;
430   *ptr = entry;
431   return entry;
432 }
433 
434 /* Remove ENTRY from the list of hooks called on duplicating edges.  */
435 void
436 symbol_table::remove_edge_duplication_hook (cgraph_2edge_hook_list *entry)
437 {
438   cgraph_2edge_hook_list **ptr = &m_first_edge_duplicated_hook;
439 
440   while (*ptr != entry)
441     ptr = &(*ptr)->next;
442   *ptr = entry->next;
443   free (entry);
444 }
445 
446 /* Call all edge duplication hooks.  */
447 void
448 symbol_table::call_edge_duplication_hooks (cgraph_edge *cs1, cgraph_edge *cs2)
449 {
450   cgraph_2edge_hook_list *entry = m_first_edge_duplicated_hook;
451   while (entry)
452   {
453     entry->hook (cs1, cs2, entry->data);
454     entry = entry->next;
455   }
456 }
457 
458 /* Register HOOK to be called with DATA on each duplicated node.  */
459 cgraph_2node_hook_list *
460 symbol_table::add_cgraph_duplication_hook (cgraph_2node_hook hook, void *data)
461 {
462   cgraph_2node_hook_list *entry;
463   cgraph_2node_hook_list **ptr = &m_first_cgraph_duplicated_hook;
464 
465   entry = (cgraph_2node_hook_list *) xmalloc (sizeof (*entry));
466   entry->hook = hook;
467   entry->data = data;
468   entry->next = NULL;
469   while (*ptr)
470     ptr = &(*ptr)->next;
471   *ptr = entry;
472   return entry;
473 }
474 
475 /* Remove ENTRY from the list of hooks called on duplicating nodes.  */
476 void
477 symbol_table::remove_cgraph_duplication_hook (cgraph_2node_hook_list *entry)
478 {
479   cgraph_2node_hook_list **ptr = &m_first_cgraph_duplicated_hook;
480 
481   while (*ptr != entry)
482     ptr = &(*ptr)->next;
483   *ptr = entry->next;
484   free (entry);
485 }
486 
487 /* Call all node duplication hooks.  */
488 void
489 symbol_table::call_cgraph_duplication_hooks (cgraph_node *node,
490 					     cgraph_node *node2)
491 {
492   cgraph_2node_hook_list *entry = m_first_cgraph_duplicated_hook;
493   while (entry)
494   {
495     entry->hook (node, node2, entry->data);
496     entry = entry->next;
497   }
498 }
499 
500 /* Return cgraph node assigned to DECL.  Create new one when needed.  */
501 
502 cgraph_node *
503 cgraph_node::create (tree decl)
504 {
505   cgraph_node *node = symtab->create_empty ();
506   gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
507 
508   node->decl = decl;
509 
510   node->count = profile_count::uninitialized ();
511 
512   if ((flag_openacc || flag_openmp)
513       && lookup_attribute ("omp declare target", DECL_ATTRIBUTES (decl)))
514     {
515       node->offloadable = 1;
516       if (ENABLE_OFFLOADING)
517 	g->have_offload = true;
518     }
519 
520   if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
521     node->ifunc_resolver = true;
522 
523   node->register_symbol ();
524 
525   if (DECL_CONTEXT (decl) && TREE_CODE (DECL_CONTEXT (decl)) == FUNCTION_DECL)
526     {
527       node->origin = cgraph_node::get_create (DECL_CONTEXT (decl));
528       node->next_nested = node->origin->nested;
529       node->origin->nested = node;
530     }
531   return node;
532 }
533 
534 /* Try to find a call graph node for declaration DECL and if it does not exist
535    or if it corresponds to an inline clone, create a new one.  */
536 
537 cgraph_node *
538 cgraph_node::get_create (tree decl)
539 {
540   cgraph_node *first_clone = cgraph_node::get (decl);
541 
542   if (first_clone && !first_clone->global.inlined_to)
543     return first_clone;
544 
545   cgraph_node *node = cgraph_node::create (decl);
546   if (first_clone)
547     {
548       first_clone->clone_of = node;
549       node->clones = first_clone;
550       symtab->symtab_prevail_in_asm_name_hash (node);
551       node->decl->decl_with_vis.symtab_node = node;
552       if (dump_file)
553 	fprintf (dump_file, "Introduced new external node "
554 		 "(%s) and turned into root of the clone tree.\n",
555 		 node->dump_name ());
556     }
557   else if (dump_file)
558     fprintf (dump_file, "Introduced new external node "
559 	     "(%s).\n", node->dump_name ());
560   return node;
561 }
562 
563 /* Mark ALIAS as an alias to DECL.  DECL_NODE is cgraph node representing
564    the function body is associated with (not necessarily cgraph_node (DECL).  */
565 
566 cgraph_node *
567 cgraph_node::create_alias (tree alias, tree target)
568 {
569   cgraph_node *alias_node;
570 
571   gcc_assert (TREE_CODE (target) == FUNCTION_DECL
572 	      || TREE_CODE (target) == IDENTIFIER_NODE);
573   gcc_assert (TREE_CODE (alias) == FUNCTION_DECL);
574   alias_node = cgraph_node::get_create (alias);
575   gcc_assert (!alias_node->definition);
576   alias_node->alias_target = target;
577   alias_node->definition = true;
578   alias_node->alias = true;
579   if (lookup_attribute ("weakref", DECL_ATTRIBUTES (alias)) != NULL)
580     alias_node->transparent_alias = alias_node->weakref = true;
581   if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (alias)))
582     alias_node->ifunc_resolver = true;
583   return alias_node;
584 }
585 
586 /* Attempt to mark ALIAS as an alias to DECL.  Return alias node if successful
587    and NULL otherwise.
588    Same body aliases are output whenever the body of DECL is output,
589    and cgraph_node::get (ALIAS) transparently returns
590    cgraph_node::get (DECL).  */
591 
592 cgraph_node *
593 cgraph_node::create_same_body_alias (tree alias, tree decl)
594 {
595   cgraph_node *n;
596 
597   /* If aliases aren't supported by the assembler, fail.  */
598   if (!TARGET_SUPPORTS_ALIASES)
599     return NULL;
600 
601   /* Langhooks can create same body aliases of symbols not defined.
602      Those are useless. Drop them on the floor.  */
603   if (symtab->global_info_ready)
604     return NULL;
605 
606   n = cgraph_node::create_alias (alias, decl);
607   n->cpp_implicit_alias = true;
608   if (symtab->cpp_implicit_aliases_done)
609     n->resolve_alias (cgraph_node::get (decl));
610   return n;
611 }
612 
613 /* Add thunk alias into callgraph.  The alias declaration is ALIAS and it
614    aliases DECL with an adjustments made into the first parameter.
615    See comments in struct cgraph_thunk_info for detail on the parameters.  */
616 
617 cgraph_node *
618 cgraph_node::create_thunk (tree alias, tree, bool this_adjusting,
619 			   HOST_WIDE_INT fixed_offset,
620 			   HOST_WIDE_INT virtual_value,
621 			   HOST_WIDE_INT indirect_offset,
622 			   tree virtual_offset,
623 			   tree real_alias)
624 {
625   cgraph_node *node;
626 
627   node = cgraph_node::get (alias);
628   if (node)
629     node->reset ();
630   else
631     node = cgraph_node::create (alias);
632 
633   /* Make sure that if VIRTUAL_OFFSET is in sync with VIRTUAL_VALUE.  */
634   gcc_checking_assert (virtual_offset
635 		       ? virtual_value == wi::to_wide (virtual_offset)
636 		       : virtual_value == 0);
637 
638   node->thunk.fixed_offset = fixed_offset;
639   node->thunk.virtual_value = virtual_value;
640   node->thunk.indirect_offset = indirect_offset;
641   node->thunk.alias = real_alias;
642   node->thunk.this_adjusting = this_adjusting;
643   node->thunk.virtual_offset_p = virtual_offset != NULL;
644   node->thunk.thunk_p = true;
645   node->definition = true;
646 
647   return node;
648 }
649 
650 /* Return the cgraph node that has ASMNAME for its DECL_ASSEMBLER_NAME.
651    Return NULL if there's no such node.  */
652 
653 cgraph_node *
654 cgraph_node::get_for_asmname (tree asmname)
655 {
656   /* We do not want to look at inline clones.  */
657   for (symtab_node *node = symtab_node::get_for_asmname (asmname);
658        node;
659        node = node->next_sharing_asm_name)
660     {
661       cgraph_node *cn = dyn_cast <cgraph_node *> (node);
662       if (cn && !cn->global.inlined_to)
663 	return cn;
664     }
665   return NULL;
666 }
667 
668 /* Returns a hash value for X (which really is a cgraph_edge).  */
669 
670 hashval_t
671 cgraph_edge_hasher::hash (cgraph_edge *e)
672 {
673   /* This is a really poor hash function, but it is what htab_hash_pointer
674      uses.  */
675   return (hashval_t) ((intptr_t)e->call_stmt >> 3);
676 }
677 
678 /* Returns a hash value for X (which really is a cgraph_edge).  */
679 
680 hashval_t
681 cgraph_edge_hasher::hash (gimple *call_stmt)
682 {
683   /* This is a really poor hash function, but it is what htab_hash_pointer
684      uses.  */
685   return (hashval_t) ((intptr_t)call_stmt >> 3);
686 }
687 
688 /* Return nonzero if the call_stmt of cgraph_edge X is stmt *Y.  */
689 
690 inline bool
691 cgraph_edge_hasher::equal (cgraph_edge *x, gimple *y)
692 {
693   return x->call_stmt == y;
694 }
695 
696 /* Add call graph edge E to call site hash of its caller.  */
697 
698 static inline void
699 cgraph_update_edge_in_call_site_hash (cgraph_edge *e)
700 {
701   gimple *call = e->call_stmt;
702   *e->caller->call_site_hash->find_slot_with_hash
703       (call, cgraph_edge_hasher::hash (call), INSERT) = e;
704 }
705 
706 /* Add call graph edge E to call site hash of its caller.  */
707 
708 static inline void
709 cgraph_add_edge_to_call_site_hash (cgraph_edge *e)
710 {
711   /* There are two speculative edges for every statement (one direct,
712      one indirect); always hash the direct one.  */
713   if (e->speculative && e->indirect_unknown_callee)
714     return;
715   cgraph_edge **slot = e->caller->call_site_hash->find_slot_with_hash
716       (e->call_stmt, cgraph_edge_hasher::hash (e->call_stmt), INSERT);
717   if (*slot)
718     {
719       gcc_assert (((cgraph_edge *)*slot)->speculative);
720       if (e->callee)
721 	*slot = e;
722       return;
723     }
724   gcc_assert (!*slot || e->speculative);
725   *slot = e;
726 }
727 
728 /* Return the callgraph edge representing the GIMPLE_CALL statement
729    CALL_STMT.  */
730 
731 cgraph_edge *
732 cgraph_node::get_edge (gimple *call_stmt)
733 {
734   cgraph_edge *e, *e2;
735   int n = 0;
736 
737   if (call_site_hash)
738     return call_site_hash->find_with_hash
739 	(call_stmt, cgraph_edge_hasher::hash (call_stmt));
740 
741   /* This loop may turn out to be performance problem.  In such case adding
742      hashtables into call nodes with very many edges is probably best
743      solution.  It is not good idea to add pointer into CALL_EXPR itself
744      because we want to make possible having multiple cgraph nodes representing
745      different clones of the same body before the body is actually cloned.  */
746   for (e = callees; e; e = e->next_callee)
747     {
748       if (e->call_stmt == call_stmt)
749 	break;
750       n++;
751     }
752 
753   if (!e)
754     for (e = indirect_calls; e; e = e->next_callee)
755       {
756 	if (e->call_stmt == call_stmt)
757 	  break;
758 	n++;
759       }
760 
761   if (n > 100)
762     {
763       call_site_hash = hash_table<cgraph_edge_hasher>::create_ggc (120);
764       for (e2 = callees; e2; e2 = e2->next_callee)
765 	cgraph_add_edge_to_call_site_hash (e2);
766       for (e2 = indirect_calls; e2; e2 = e2->next_callee)
767 	cgraph_add_edge_to_call_site_hash (e2);
768     }
769 
770   return e;
771 }
772 
773 
774 /* Change field call_stmt of edge to NEW_STMT.
775    If UPDATE_SPECULATIVE and E is any component of speculative
776    edge, then update all components.  */
777 
778 void
779 cgraph_edge::set_call_stmt (gcall *new_stmt, bool update_speculative)
780 {
781   tree decl;
782 
783   /* Speculative edges has three component, update all of them
784      when asked to.  */
785   if (update_speculative && speculative)
786     {
787       cgraph_edge *direct, *indirect;
788       ipa_ref *ref;
789 
790       speculative_call_info (direct, indirect, ref);
791       direct->set_call_stmt (new_stmt, false);
792       indirect->set_call_stmt (new_stmt, false);
793       ref->stmt = new_stmt;
794       return;
795     }
796 
797   /* Only direct speculative edges go to call_site_hash.  */
798   if (caller->call_site_hash
799       && (!speculative || !indirect_unknown_callee))
800     {
801       caller->call_site_hash->remove_elt_with_hash
802 	(call_stmt, cgraph_edge_hasher::hash (call_stmt));
803     }
804 
805   cgraph_edge *e = this;
806 
807   call_stmt = new_stmt;
808   if (indirect_unknown_callee
809       && (decl = gimple_call_fndecl (new_stmt)))
810     {
811       /* Constant propagation (and possibly also inlining?) can turn an
812 	 indirect call into a direct one.  */
813       cgraph_node *new_callee = cgraph_node::get (decl);
814 
815       gcc_checking_assert (new_callee);
816       e = make_direct (new_callee);
817     }
818 
819   function *fun = DECL_STRUCT_FUNCTION (e->caller->decl);
820   e->can_throw_external = stmt_can_throw_external (fun, new_stmt);
821   if (e->caller->call_site_hash)
822     cgraph_add_edge_to_call_site_hash (e);
823 }
824 
825 /* Allocate a cgraph_edge structure and fill it with data according to the
826    parameters of which only CALLEE can be NULL (when creating an indirect call
827    edge).  */
828 
829 cgraph_edge *
830 symbol_table::create_edge (cgraph_node *caller, cgraph_node *callee,
831 			   gcall *call_stmt, profile_count count,
832 			   bool indir_unknown_callee)
833 {
834   cgraph_edge *edge;
835 
836   /* LTO does not actually have access to the call_stmt since these
837      have not been loaded yet.  */
838   if (call_stmt)
839     {
840       /* This is a rather expensive check possibly triggering
841 	 construction of call stmt hashtable.  */
842       cgraph_edge *e;
843       gcc_checking_assert (!(e = caller->get_edge (call_stmt))
844 			   || e->speculative);
845 
846       gcc_assert (is_gimple_call (call_stmt));
847     }
848 
849   if (free_edges)
850     {
851       edge = free_edges;
852       free_edges = NEXT_FREE_EDGE (edge);
853     }
854   else
855     {
856       edge = ggc_alloc<cgraph_edge> ();
857       edge->m_summary_id = -1;
858     }
859 
860   edges_count++;
861 
862   gcc_assert (++edges_max_uid != 0);
863   edge->m_uid = edges_max_uid;
864   edge->aux = NULL;
865   edge->caller = caller;
866   edge->callee = callee;
867   edge->prev_caller = NULL;
868   edge->next_caller = NULL;
869   edge->prev_callee = NULL;
870   edge->next_callee = NULL;
871   edge->lto_stmt_uid = 0;
872 
873   edge->count = count;
874 
875   edge->call_stmt = call_stmt;
876   edge->can_throw_external
877     = call_stmt ? stmt_can_throw_external (DECL_STRUCT_FUNCTION (caller->decl),
878 					   call_stmt) : false;
879   if (call_stmt
880       && callee && callee->decl
881       && !gimple_check_call_matching_types (call_stmt, callee->decl,
882 					    false))
883     {
884       edge->inline_failed = CIF_MISMATCHED_ARGUMENTS;
885       edge->call_stmt_cannot_inline_p = true;
886     }
887   else
888     {
889       edge->inline_failed = CIF_FUNCTION_NOT_CONSIDERED;
890       edge->call_stmt_cannot_inline_p = false;
891     }
892 
893   edge->indirect_info = NULL;
894   edge->indirect_inlining_edge = 0;
895   edge->speculative = false;
896   edge->indirect_unknown_callee = indir_unknown_callee;
897   if (opt_for_fn (edge->caller->decl, flag_devirtualize)
898       && call_stmt && DECL_STRUCT_FUNCTION (caller->decl))
899     edge->in_polymorphic_cdtor
900       = decl_maybe_in_construction_p (NULL, NULL, call_stmt,
901 				      caller->decl);
902   else
903     edge->in_polymorphic_cdtor = caller->thunk.thunk_p;
904   if (call_stmt && caller->call_site_hash)
905     cgraph_add_edge_to_call_site_hash (edge);
906 
907   return edge;
908 }
909 
910 /* Create edge from a given function to CALLEE in the cgraph.  */
911 
912 cgraph_edge *
913 cgraph_node::create_edge (cgraph_node *callee,
914 			  gcall *call_stmt, profile_count count)
915 {
916   cgraph_edge *edge = symtab->create_edge (this, callee, call_stmt, count,
917 					   false);
918 
919   initialize_inline_failed (edge);
920 
921   edge->next_caller = callee->callers;
922   if (callee->callers)
923     callee->callers->prev_caller = edge;
924   edge->next_callee = callees;
925   if (callees)
926     callees->prev_callee = edge;
927   callees = edge;
928   callee->callers = edge;
929 
930   return edge;
931 }
932 
933 /* Allocate cgraph_indirect_call_info and set its fields to default values. */
934 
935 cgraph_indirect_call_info *
936 cgraph_allocate_init_indirect_info (void)
937 {
938   cgraph_indirect_call_info *ii;
939 
940   ii = ggc_cleared_alloc<cgraph_indirect_call_info> ();
941   ii->param_index = -1;
942   return ii;
943 }
944 
945 /* Create an indirect edge with a yet-undetermined callee where the call
946    statement destination is a formal parameter of the caller with index
947    PARAM_INDEX. */
948 
949 cgraph_edge *
950 cgraph_node::create_indirect_edge (gcall *call_stmt, int ecf_flags,
951 				   profile_count count,
952 				   bool compute_indirect_info)
953 {
954   cgraph_edge *edge = symtab->create_edge (this, NULL, call_stmt,
955 							    count, true);
956   tree target;
957 
958   initialize_inline_failed (edge);
959 
960   edge->indirect_info = cgraph_allocate_init_indirect_info ();
961   edge->indirect_info->ecf_flags = ecf_flags;
962   edge->indirect_info->vptr_changed = true;
963 
964   /* Record polymorphic call info.  */
965   if (compute_indirect_info
966       && call_stmt
967       && (target = gimple_call_fn (call_stmt))
968       && virtual_method_call_p (target))
969     {
970       ipa_polymorphic_call_context context (decl, target, call_stmt);
971 
972       /* Only record types can have virtual calls.  */
973       edge->indirect_info->polymorphic = true;
974       edge->indirect_info->param_index = -1;
975       edge->indirect_info->otr_token
976 	 = tree_to_uhwi (OBJ_TYPE_REF_TOKEN (target));
977       edge->indirect_info->otr_type = obj_type_ref_class (target);
978       gcc_assert (TREE_CODE (edge->indirect_info->otr_type) == RECORD_TYPE);
979       edge->indirect_info->context = context;
980     }
981 
982   edge->next_callee = indirect_calls;
983   if (indirect_calls)
984     indirect_calls->prev_callee = edge;
985   indirect_calls = edge;
986 
987   return edge;
988 }
989 
990 /* Remove the edge from the list of the callees of the caller.  */
991 
992 void
993 cgraph_edge::remove_caller (void)
994 {
995   if (prev_callee)
996     prev_callee->next_callee = next_callee;
997   if (next_callee)
998     next_callee->prev_callee = prev_callee;
999   if (!prev_callee)
1000     {
1001       if (indirect_unknown_callee)
1002 	caller->indirect_calls = next_callee;
1003       else
1004 	caller->callees = next_callee;
1005     }
1006   if (caller->call_site_hash)
1007     caller->call_site_hash->remove_elt_with_hash
1008 	(call_stmt, cgraph_edge_hasher::hash (call_stmt));
1009 }
1010 
1011 /* Put the edge onto the free list.  */
1012 
1013 void
1014 symbol_table::free_edge (cgraph_edge *e)
1015 {
1016   if (e->indirect_info)
1017     ggc_free (e->indirect_info);
1018 
1019   /* Clear out the edge so we do not dangle pointers.  */
1020   int summary_id = e->m_summary_id;
1021   memset (e, 0, sizeof (*e));
1022   e->m_summary_id = summary_id;
1023   NEXT_FREE_EDGE (e) = free_edges;
1024   free_edges = e;
1025   edges_count--;
1026 }
1027 
1028 /* Remove the edge in the cgraph.  */
1029 
1030 void
1031 cgraph_edge::remove (void)
1032 {
1033   /* Call all edge removal hooks.  */
1034   symtab->call_edge_removal_hooks (this);
1035 
1036   if (!indirect_unknown_callee)
1037     /* Remove from callers list of the callee.  */
1038     remove_callee ();
1039 
1040   /* Remove from callees list of the callers.  */
1041   remove_caller ();
1042 
1043   /* Put the edge onto the free list.  */
1044   symtab->free_edge (this);
1045 }
1046 
1047 /* Turn edge into speculative call calling N2. Update
1048    the profile so the direct call is taken COUNT times
1049    with FREQUENCY.
1050 
1051    At clone materialization time, the indirect call E will
1052    be expanded as:
1053 
1054    if (call_dest == N2)
1055      n2 ();
1056    else
1057      call call_dest
1058 
1059    At this time the function just creates the direct call,
1060    the referencd representing the if conditional and attaches
1061    them all to the orginal indirect call statement.
1062 
1063    Return direct edge created.  */
1064 
1065 cgraph_edge *
1066 cgraph_edge::make_speculative (cgraph_node *n2, profile_count direct_count)
1067 {
1068   cgraph_node *n = caller;
1069   ipa_ref *ref = NULL;
1070   cgraph_edge *e2;
1071 
1072   if (dump_file)
1073     fprintf (dump_file, "Indirect call -> speculative call %s => %s\n",
1074 	     n->dump_name (), n2->dump_name ());
1075   speculative = true;
1076   e2 = n->create_edge (n2, call_stmt, direct_count);
1077   initialize_inline_failed (e2);
1078   e2->speculative = true;
1079   if (TREE_NOTHROW (n2->decl))
1080     e2->can_throw_external = false;
1081   else
1082     e2->can_throw_external = can_throw_external;
1083   e2->lto_stmt_uid = lto_stmt_uid;
1084   e2->in_polymorphic_cdtor = in_polymorphic_cdtor;
1085   count -= e2->count;
1086   symtab->call_edge_duplication_hooks (this, e2);
1087   ref = n->create_reference (n2, IPA_REF_ADDR, call_stmt);
1088   ref->lto_stmt_uid = lto_stmt_uid;
1089   ref->speculative = speculative;
1090   n2->mark_address_taken ();
1091   return e2;
1092 }
1093 
1094 /* Speculative call consist of three components:
1095    1) an indirect edge representing the original call
1096    2) an direct edge representing the new call
1097    3) ADDR_EXPR reference representing the speculative check.
1098    All three components are attached to single statement (the indirect
1099    call) and if one of them exists, all of them must exist.
1100 
1101    Given speculative call edge, return all three components.
1102  */
1103 
1104 void
1105 cgraph_edge::speculative_call_info (cgraph_edge *&direct,
1106 				    cgraph_edge *&indirect,
1107 				    ipa_ref *&reference)
1108 {
1109   ipa_ref *ref;
1110   int i;
1111   cgraph_edge *e2;
1112   cgraph_edge *e = this;
1113 
1114   if (!e->indirect_unknown_callee)
1115     for (e2 = e->caller->indirect_calls;
1116 	 e2->call_stmt != e->call_stmt || e2->lto_stmt_uid != e->lto_stmt_uid;
1117 	 e2 = e2->next_callee)
1118       ;
1119   else
1120     {
1121       e2 = e;
1122       /* We can take advantage of the call stmt hash.  */
1123       if (e2->call_stmt)
1124 	{
1125 	  e = e->caller->get_edge (e2->call_stmt);
1126 	  gcc_assert (e->speculative && !e->indirect_unknown_callee);
1127 	}
1128       else
1129 	for (e = e->caller->callees;
1130 	     e2->call_stmt != e->call_stmt
1131 	     || e2->lto_stmt_uid != e->lto_stmt_uid;
1132 	     e = e->next_callee)
1133 	  ;
1134     }
1135   gcc_assert (e->speculative && e2->speculative);
1136   direct = e;
1137   indirect = e2;
1138 
1139   reference = NULL;
1140   for (i = 0; e->caller->iterate_reference (i, ref); i++)
1141     if (ref->speculative
1142 	&& ((ref->stmt && ref->stmt == e->call_stmt)
1143 	    || (!ref->stmt && ref->lto_stmt_uid == e->lto_stmt_uid)))
1144       {
1145 	reference = ref;
1146 	break;
1147       }
1148 
1149   /* Speculative edge always consist of all three components - direct edge,
1150      indirect and reference.  */
1151 
1152   gcc_assert (e && e2 && ref);
1153 }
1154 
1155 /* Speculative call edge turned out to be direct call to CALLE_DECL.
1156    Remove the speculative call sequence and return edge representing the call.
1157    It is up to caller to redirect the call as appropriate. */
1158 
1159 cgraph_edge *
1160 cgraph_edge::resolve_speculation (tree callee_decl)
1161 {
1162   cgraph_edge *edge = this;
1163   cgraph_edge *e2;
1164   ipa_ref *ref;
1165 
1166   gcc_assert (edge->speculative);
1167   edge->speculative_call_info (e2, edge, ref);
1168   if (!callee_decl
1169       || !ref->referred->semantically_equivalent_p
1170 	   (symtab_node::get (callee_decl)))
1171     {
1172       if (dump_file)
1173 	{
1174 	  if (callee_decl)
1175 	    {
1176 	      fprintf (dump_file, "Speculative indirect call %s => %s has "
1177 		       "turned out to have contradicting known target ",
1178 		       edge->caller->dump_name (),
1179 		       e2->callee->dump_name ());
1180 	      print_generic_expr (dump_file, callee_decl);
1181 	      fprintf (dump_file, "\n");
1182 	    }
1183 	  else
1184 	    {
1185 	      fprintf (dump_file, "Removing speculative call %s => %s\n",
1186 		       edge->caller->dump_name (),
1187 		       e2->callee->dump_name ());
1188 	    }
1189 	}
1190     }
1191   else
1192     {
1193       cgraph_edge *tmp = edge;
1194       if (dump_file)
1195         fprintf (dump_file, "Speculative call turned into direct call.\n");
1196       edge = e2;
1197       e2 = tmp;
1198       /* FIXME:  If EDGE is inlined, we should scale up the frequencies and counts
1199          in the functions inlined through it.  */
1200     }
1201   edge->count += e2->count;
1202   edge->speculative = false;
1203   e2->speculative = false;
1204   ref->remove_reference ();
1205   if (e2->indirect_unknown_callee || e2->inline_failed)
1206     e2->remove ();
1207   else
1208     e2->callee->remove_symbol_and_inline_clones ();
1209   if (edge->caller->call_site_hash)
1210     cgraph_update_edge_in_call_site_hash (edge);
1211   return edge;
1212 }
1213 
1214 /* Make an indirect edge with an unknown callee an ordinary edge leading to
1215    CALLEE.  DELTA is an integer constant that is to be added to the this
1216    pointer (first parameter) to compensate for skipping a thunk adjustment.  */
1217 
1218 cgraph_edge *
1219 cgraph_edge::make_direct (cgraph_node *callee)
1220 {
1221   cgraph_edge *edge = this;
1222   gcc_assert (indirect_unknown_callee);
1223 
1224   /* If we are redirecting speculative call, make it non-speculative.  */
1225   if (indirect_unknown_callee && speculative)
1226     {
1227       edge = edge->resolve_speculation (callee->decl);
1228 
1229       /* On successful speculation just return the pre existing direct edge.  */
1230       if (!indirect_unknown_callee)
1231         return edge;
1232     }
1233 
1234   indirect_unknown_callee = 0;
1235   ggc_free (indirect_info);
1236   indirect_info = NULL;
1237 
1238   /* Get the edge out of the indirect edge list. */
1239   if (prev_callee)
1240     prev_callee->next_callee = next_callee;
1241   if (next_callee)
1242     next_callee->prev_callee = prev_callee;
1243   if (!prev_callee)
1244     caller->indirect_calls = next_callee;
1245 
1246   /* Put it into the normal callee list */
1247   prev_callee = NULL;
1248   next_callee = caller->callees;
1249   if (caller->callees)
1250     caller->callees->prev_callee = edge;
1251   caller->callees = edge;
1252 
1253   /* Insert to callers list of the new callee.  */
1254   edge->set_callee (callee);
1255 
1256   if (call_stmt
1257       && !gimple_check_call_matching_types (call_stmt, callee->decl, false))
1258     {
1259       call_stmt_cannot_inline_p = true;
1260       inline_failed = CIF_MISMATCHED_ARGUMENTS;
1261     }
1262 
1263   /* We need to re-determine the inlining status of the edge.  */
1264   initialize_inline_failed (edge);
1265   return edge;
1266 }
1267 
1268 /* If necessary, change the function declaration in the call statement
1269    associated with E so that it corresponds to the edge callee.  */
1270 
1271 gimple *
1272 cgraph_edge::redirect_call_stmt_to_callee (void)
1273 {
1274   cgraph_edge *e = this;
1275 
1276   tree decl = gimple_call_fndecl (e->call_stmt);
1277   gcall *new_stmt;
1278   gimple_stmt_iterator gsi;
1279 
1280   if (e->speculative)
1281     {
1282       cgraph_edge *e2;
1283       gcall *new_stmt;
1284       ipa_ref *ref;
1285 
1286       e->speculative_call_info (e, e2, ref);
1287       /* If there already is an direct call (i.e. as a result of inliner's
1288 	 substitution), forget about speculating.  */
1289       if (decl)
1290 	e = e->resolve_speculation (decl);
1291       /* If types do not match, speculation was likely wrong.
1292          The direct edge was possibly redirected to the clone with a different
1293 	 signature.  We did not update the call statement yet, so compare it
1294 	 with the reference that still points to the proper type.  */
1295       else if (!gimple_check_call_matching_types (e->call_stmt,
1296 						  ref->referred->decl,
1297 						  true))
1298 	{
1299 	  if (dump_file)
1300 	    fprintf (dump_file, "Not expanding speculative call of %s -> %s\n"
1301 		     "Type mismatch.\n",
1302 		     e->caller->dump_name (),
1303 		     e->callee->dump_name ());
1304 	  e = e->resolve_speculation ();
1305 	  /* We are producing the final function body and will throw away the
1306 	     callgraph edges really soon.  Reset the counts/frequencies to
1307 	     keep verifier happy in the case of roundoff errors.  */
1308 	  e->count = gimple_bb (e->call_stmt)->count;
1309 	}
1310       /* Expand speculation into GIMPLE code.  */
1311       else
1312 	{
1313 	  if (dump_file)
1314 	    {
1315 	      fprintf (dump_file,
1316 		       "Expanding speculative call of %s -> %s count: ",
1317 		       e->caller->dump_name (),
1318 		       e->callee->dump_name ());
1319 	      e->count.dump (dump_file);
1320 	      fprintf (dump_file, "\n");
1321 	    }
1322 	  gcc_assert (e2->speculative);
1323 	  push_cfun (DECL_STRUCT_FUNCTION (e->caller->decl));
1324 
1325 	  profile_probability prob = e->count.probability_in (e->count
1326 							      + e2->count);
1327 	  if (!prob.initialized_p ())
1328 	    prob = profile_probability::even ();
1329 	  new_stmt = gimple_ic (e->call_stmt,
1330 				dyn_cast<cgraph_node *> (ref->referred),
1331 				prob);
1332 	  e->speculative = false;
1333 	  e->caller->set_call_stmt_including_clones (e->call_stmt, new_stmt,
1334 						     false);
1335 	  e->count = gimple_bb (e->call_stmt)->count;
1336 	  e2->speculative = false;
1337 	  e2->count = gimple_bb (e2->call_stmt)->count;
1338 	  ref->speculative = false;
1339 	  ref->stmt = NULL;
1340 	  /* Indirect edges are not both in the call site hash.
1341 	     get it updated.  */
1342 	  if (e->caller->call_site_hash)
1343 	    cgraph_update_edge_in_call_site_hash (e2);
1344 	  pop_cfun ();
1345 	  /* Continue redirecting E to proper target.  */
1346 	}
1347     }
1348 
1349 
1350   if (e->indirect_unknown_callee
1351       || decl == e->callee->decl)
1352     return e->call_stmt;
1353 
1354   if (flag_checking && decl)
1355     {
1356       cgraph_node *node = cgraph_node::get (decl);
1357       gcc_assert (!node || !node->clone.combined_args_to_skip);
1358     }
1359 
1360   if (symtab->dump_file)
1361     {
1362       fprintf (symtab->dump_file, "updating call of %s -> %s: ",
1363 	       e->caller->dump_name (), e->callee->dump_name ());
1364       print_gimple_stmt (symtab->dump_file, e->call_stmt, 0, dump_flags);
1365       if (e->callee->clone.combined_args_to_skip)
1366 	{
1367 	  fprintf (symtab->dump_file, " combined args to skip: ");
1368 	  dump_bitmap (symtab->dump_file,
1369 		       e->callee->clone.combined_args_to_skip);
1370 	}
1371     }
1372 
1373   if (e->callee->clone.combined_args_to_skip)
1374     {
1375       int lp_nr;
1376 
1377       new_stmt = e->call_stmt;
1378       if (e->callee->clone.combined_args_to_skip)
1379 	new_stmt
1380 	  = gimple_call_copy_skip_args (new_stmt,
1381 					e->callee->clone.combined_args_to_skip);
1382       tree old_fntype = gimple_call_fntype (e->call_stmt);
1383       gimple_call_set_fndecl (new_stmt, e->callee->decl);
1384       cgraph_node *origin = e->callee;
1385       while (origin->clone_of)
1386 	origin = origin->clone_of;
1387 
1388       if ((origin->former_clone_of
1389 	   && old_fntype == TREE_TYPE (origin->former_clone_of))
1390 	  || old_fntype == TREE_TYPE (origin->decl))
1391 	gimple_call_set_fntype (new_stmt, TREE_TYPE (e->callee->decl));
1392       else
1393 	{
1394 	  bitmap skip = e->callee->clone.combined_args_to_skip;
1395 	  tree t = cgraph_build_function_type_skip_args (old_fntype, skip,
1396 							 false);
1397 	  gimple_call_set_fntype (new_stmt, t);
1398 	}
1399 
1400       if (gimple_vdef (new_stmt)
1401 	  && TREE_CODE (gimple_vdef (new_stmt)) == SSA_NAME)
1402 	SSA_NAME_DEF_STMT (gimple_vdef (new_stmt)) = new_stmt;
1403 
1404       gsi = gsi_for_stmt (e->call_stmt);
1405 
1406       /* For optimized away parameters, add on the caller side
1407 	 before the call
1408 	 DEBUG D#X => parm_Y(D)
1409 	 stmts and associate D#X with parm in decl_debug_args_lookup
1410 	 vector to say for debug info that if parameter parm had been passed,
1411 	 it would have value parm_Y(D).  */
1412       if (e->callee->clone.combined_args_to_skip && MAY_HAVE_DEBUG_BIND_STMTS)
1413 	{
1414 	  vec<tree, va_gc> **debug_args
1415 	    = decl_debug_args_lookup (e->callee->decl);
1416 	  tree old_decl = gimple_call_fndecl (e->call_stmt);
1417 	  if (debug_args && old_decl)
1418 	    {
1419 	      tree parm;
1420 	      unsigned i = 0, num;
1421 	      unsigned len = vec_safe_length (*debug_args);
1422 	      unsigned nargs = gimple_call_num_args (e->call_stmt);
1423 	      for (parm = DECL_ARGUMENTS (old_decl), num = 0;
1424 		   parm && num < nargs;
1425 		   parm = DECL_CHAIN (parm), num++)
1426 		if (bitmap_bit_p (e->callee->clone.combined_args_to_skip, num)
1427 		    && is_gimple_reg (parm))
1428 		  {
1429 		    unsigned last = i;
1430 
1431 		    while (i < len && (**debug_args)[i] != DECL_ORIGIN (parm))
1432 		      i += 2;
1433 		    if (i >= len)
1434 		      {
1435 			i = 0;
1436 			while (i < last
1437 			       && (**debug_args)[i] != DECL_ORIGIN (parm))
1438 			  i += 2;
1439 			if (i >= last)
1440 			  continue;
1441 		      }
1442 		    tree ddecl = (**debug_args)[i + 1];
1443 		    tree arg = gimple_call_arg (e->call_stmt, num);
1444 		    if (!useless_type_conversion_p (TREE_TYPE (ddecl),
1445 						    TREE_TYPE (arg)))
1446 		      {
1447 			tree rhs1;
1448 			if (!fold_convertible_p (TREE_TYPE (ddecl), arg))
1449 			  continue;
1450 			if (TREE_CODE (arg) == SSA_NAME
1451 			    && gimple_assign_cast_p (SSA_NAME_DEF_STMT (arg))
1452 			    && (rhs1
1453 				= gimple_assign_rhs1 (SSA_NAME_DEF_STMT (arg)))
1454 			    && useless_type_conversion_p (TREE_TYPE (ddecl),
1455 							  TREE_TYPE (rhs1)))
1456 			  arg = rhs1;
1457 			else
1458 			  arg = fold_convert (TREE_TYPE (ddecl), arg);
1459 		      }
1460 
1461 		    gimple *def_temp
1462 		      = gimple_build_debug_bind (ddecl, unshare_expr (arg),
1463 						 e->call_stmt);
1464 		    gsi_insert_before (&gsi, def_temp, GSI_SAME_STMT);
1465 		  }
1466 	    }
1467 	}
1468 
1469       gsi_replace (&gsi, new_stmt, false);
1470       /* We need to defer cleaning EH info on the new statement to
1471          fixup-cfg.  We may not have dominator information at this point
1472 	 and thus would end up with unreachable blocks and have no way
1473 	 to communicate that we need to run CFG cleanup then.  */
1474       lp_nr = lookup_stmt_eh_lp (e->call_stmt);
1475       if (lp_nr != 0)
1476 	{
1477 	  remove_stmt_from_eh_lp (e->call_stmt);
1478 	  add_stmt_to_eh_lp (new_stmt, lp_nr);
1479 	}
1480     }
1481   else
1482     {
1483       new_stmt = e->call_stmt;
1484       gimple_call_set_fndecl (new_stmt, e->callee->decl);
1485       update_stmt_fn (DECL_STRUCT_FUNCTION (e->caller->decl), new_stmt);
1486     }
1487 
1488   /* If changing the call to __cxa_pure_virtual or similar noreturn function,
1489      adjust gimple_call_fntype too.  */
1490   if (gimple_call_noreturn_p (new_stmt)
1491       && VOID_TYPE_P (TREE_TYPE (TREE_TYPE (e->callee->decl)))
1492       && TYPE_ARG_TYPES (TREE_TYPE (e->callee->decl))
1493       && (TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (e->callee->decl)))
1494 	  == void_type_node))
1495     gimple_call_set_fntype (new_stmt, TREE_TYPE (e->callee->decl));
1496 
1497   /* If the call becomes noreturn, remove the LHS if possible.  */
1498   tree lhs = gimple_call_lhs (new_stmt);
1499   if (lhs
1500       && gimple_call_noreturn_p (new_stmt)
1501       && (VOID_TYPE_P (TREE_TYPE (gimple_call_fntype (new_stmt)))
1502 	  || should_remove_lhs_p (lhs)))
1503     {
1504       if (TREE_CODE (lhs) == SSA_NAME)
1505 	{
1506 	  tree var = create_tmp_reg_fn (DECL_STRUCT_FUNCTION (e->caller->decl),
1507 					TREE_TYPE (lhs), NULL);
1508 	  var = get_or_create_ssa_default_def
1509 		  (DECL_STRUCT_FUNCTION (e->caller->decl), var);
1510 	  gimple *set_stmt = gimple_build_assign (lhs, var);
1511           gsi = gsi_for_stmt (new_stmt);
1512 	  gsi_insert_before_without_update (&gsi, set_stmt, GSI_SAME_STMT);
1513 	  update_stmt_fn (DECL_STRUCT_FUNCTION (e->caller->decl), set_stmt);
1514 	}
1515       gimple_call_set_lhs (new_stmt, NULL_TREE);
1516       update_stmt_fn (DECL_STRUCT_FUNCTION (e->caller->decl), new_stmt);
1517     }
1518 
1519   /* If new callee has no static chain, remove it.  */
1520   if (gimple_call_chain (new_stmt) && !DECL_STATIC_CHAIN (e->callee->decl))
1521     {
1522       gimple_call_set_chain (new_stmt, NULL);
1523       update_stmt_fn (DECL_STRUCT_FUNCTION (e->caller->decl), new_stmt);
1524     }
1525 
1526   maybe_remove_unused_call_args (DECL_STRUCT_FUNCTION (e->caller->decl),
1527 				 new_stmt);
1528 
1529   e->caller->set_call_stmt_including_clones (e->call_stmt, new_stmt, false);
1530 
1531   if (symtab->dump_file)
1532     {
1533       fprintf (symtab->dump_file, "  updated to:");
1534       print_gimple_stmt (symtab->dump_file, e->call_stmt, 0, dump_flags);
1535     }
1536   return new_stmt;
1537 }
1538 
1539 /* Update or remove the corresponding cgraph edge if a GIMPLE_CALL
1540    OLD_STMT changed into NEW_STMT.  OLD_CALL is gimple_call_fndecl
1541    of OLD_STMT if it was previously call statement.
1542    If NEW_STMT is NULL, the call has been dropped without any
1543    replacement.  */
1544 
1545 static void
1546 cgraph_update_edges_for_call_stmt_node (cgraph_node *node,
1547 					gimple *old_stmt, tree old_call,
1548 					gimple *new_stmt)
1549 {
1550   tree new_call = (new_stmt && is_gimple_call (new_stmt))
1551 		  ? gimple_call_fndecl (new_stmt) : 0;
1552 
1553   /* We are seeing indirect calls, then there is nothing to update.  */
1554   if (!new_call && !old_call)
1555     return;
1556   /* See if we turned indirect call into direct call or folded call to one builtin
1557      into different builtin.  */
1558   if (old_call != new_call)
1559     {
1560       cgraph_edge *e = node->get_edge (old_stmt);
1561       cgraph_edge *ne = NULL;
1562       profile_count count;
1563 
1564       if (e)
1565 	{
1566 	  /* Keep calls marked as dead dead.  */
1567 	  if (new_stmt && is_gimple_call (new_stmt) && e->callee
1568 	      && fndecl_built_in_p (e->callee->decl, BUILT_IN_UNREACHABLE))
1569 	    {
1570               node->get_edge (old_stmt)->set_call_stmt
1571 		 (as_a <gcall *> (new_stmt));
1572 	      return;
1573 	    }
1574 	  /* See if the edge is already there and has the correct callee.  It
1575 	     might be so because of indirect inlining has already updated
1576 	     it.  We also might've cloned and redirected the edge.  */
1577 	  if (new_call && e->callee)
1578 	    {
1579 	      cgraph_node *callee = e->callee;
1580 	      while (callee)
1581 		{
1582 		  if (callee->decl == new_call
1583 		      || callee->former_clone_of == new_call)
1584 		    {
1585 		      e->set_call_stmt (as_a <gcall *> (new_stmt));
1586 		      return;
1587 		    }
1588 		  callee = callee->clone_of;
1589 		}
1590 	    }
1591 
1592 	  /* Otherwise remove edge and create new one; we can't simply redirect
1593 	     since function has changed, so inline plan and other information
1594 	     attached to edge is invalid.  */
1595 	  count = e->count;
1596  	  if (e->indirect_unknown_callee || e->inline_failed)
1597 	    e->remove ();
1598 	  else
1599 	    e->callee->remove_symbol_and_inline_clones ();
1600 	}
1601       else if (new_call)
1602 	{
1603 	  /* We are seeing new direct call; compute profile info based on BB.  */
1604 	  basic_block bb = gimple_bb (new_stmt);
1605 	  count = bb->count;
1606 	}
1607 
1608       if (new_call)
1609 	{
1610 	  ne = node->create_edge (cgraph_node::get_create (new_call),
1611 				  as_a <gcall *> (new_stmt), count);
1612 	  gcc_assert (ne->inline_failed);
1613 	}
1614     }
1615   /* We only updated the call stmt; update pointer in cgraph edge..  */
1616   else if (old_stmt != new_stmt)
1617     node->get_edge (old_stmt)->set_call_stmt (as_a <gcall *> (new_stmt));
1618 }
1619 
1620 /* Update or remove the corresponding cgraph edge if a GIMPLE_CALL
1621    OLD_STMT changed into NEW_STMT.  OLD_DECL is gimple_call_fndecl
1622    of OLD_STMT before it was updated (updating can happen inplace).  */
1623 
1624 void
1625 cgraph_update_edges_for_call_stmt (gimple *old_stmt, tree old_decl,
1626 				   gimple *new_stmt)
1627 {
1628   cgraph_node *orig = cgraph_node::get (cfun->decl);
1629   cgraph_node *node;
1630 
1631   gcc_checking_assert (orig);
1632   cgraph_update_edges_for_call_stmt_node (orig, old_stmt, old_decl, new_stmt);
1633   if (orig->clones)
1634     for (node = orig->clones; node != orig;)
1635       {
1636         cgraph_update_edges_for_call_stmt_node (node, old_stmt, old_decl, new_stmt);
1637 	if (node->clones)
1638 	  node = node->clones;
1639 	else if (node->next_sibling_clone)
1640 	  node = node->next_sibling_clone;
1641 	else
1642 	  {
1643 	    while (node != orig && !node->next_sibling_clone)
1644 	      node = node->clone_of;
1645 	    if (node != orig)
1646 	      node = node->next_sibling_clone;
1647 	  }
1648       }
1649 }
1650 
1651 
1652 /* Remove all callees from the node.  */
1653 
1654 void
1655 cgraph_node::remove_callees (void)
1656 {
1657   cgraph_edge *e, *f;
1658 
1659   /* It is sufficient to remove the edges from the lists of callers of
1660      the callees.  The callee list of the node can be zapped with one
1661      assignment.  */
1662   for (e = callees; e; e = f)
1663     {
1664       f = e->next_callee;
1665       symtab->call_edge_removal_hooks (e);
1666       if (!e->indirect_unknown_callee)
1667 	e->remove_callee ();
1668       symtab->free_edge (e);
1669     }
1670   for (e = indirect_calls; e; e = f)
1671     {
1672       f = e->next_callee;
1673       symtab->call_edge_removal_hooks (e);
1674       if (!e->indirect_unknown_callee)
1675 	e->remove_callee ();
1676       symtab->free_edge (e);
1677     }
1678   indirect_calls = NULL;
1679   callees = NULL;
1680   if (call_site_hash)
1681     {
1682       call_site_hash->empty ();
1683       call_site_hash = NULL;
1684     }
1685 }
1686 
1687 /* Remove all callers from the node.  */
1688 
1689 void
1690 cgraph_node::remove_callers (void)
1691 {
1692   cgraph_edge *e, *f;
1693 
1694   /* It is sufficient to remove the edges from the lists of callees of
1695      the callers.  The caller list of the node can be zapped with one
1696      assignment.  */
1697   for (e = callers; e; e = f)
1698     {
1699       f = e->next_caller;
1700       symtab->call_edge_removal_hooks (e);
1701       e->remove_caller ();
1702       symtab->free_edge (e);
1703     }
1704   callers = NULL;
1705 }
1706 
1707 /* Helper function for cgraph_release_function_body and free_lang_data.
1708    It releases body from function DECL without having to inspect its
1709    possibly non-existent symtab node.  */
1710 
1711 void
1712 release_function_body (tree decl)
1713 {
1714   function *fn = DECL_STRUCT_FUNCTION (decl);
1715   if (fn)
1716     {
1717       if (fn->cfg
1718 	  && loops_for_fn (fn))
1719 	{
1720 	  fn->curr_properties &= ~PROP_loops;
1721 	  loop_optimizer_finalize (fn);
1722 	}
1723       if (fn->gimple_df)
1724 	{
1725 	  delete_tree_ssa (fn);
1726 	  fn->eh = NULL;
1727 	}
1728       if (fn->cfg)
1729 	{
1730 	  gcc_assert (!dom_info_available_p (fn, CDI_DOMINATORS));
1731 	  gcc_assert (!dom_info_available_p (fn, CDI_POST_DOMINATORS));
1732 	  delete_tree_cfg_annotations (fn);
1733 	  clear_edges (fn);
1734 	  fn->cfg = NULL;
1735 	}
1736       if (fn->value_histograms)
1737 	free_histograms (fn);
1738       gimple_set_body (decl, NULL);
1739       /* Struct function hangs a lot of data that would leak if we didn't
1740          removed all pointers to it.   */
1741       ggc_free (fn);
1742       DECL_STRUCT_FUNCTION (decl) = NULL;
1743     }
1744   DECL_SAVED_TREE (decl) = NULL;
1745 }
1746 
1747 /* Release memory used to represent body of function.
1748    Use this only for functions that are released before being translated to
1749    target code (i.e. RTL).  Functions that are compiled to RTL and beyond
1750    are free'd in final.c via free_after_compilation().
1751    KEEP_ARGUMENTS are useful only if you want to rebuild body as thunk.  */
1752 
1753 void
1754 cgraph_node::release_body (bool keep_arguments)
1755 {
1756   ipa_transforms_to_apply.release ();
1757   if (!used_as_abstract_origin && symtab->state != PARSING)
1758     {
1759       DECL_RESULT (decl) = NULL;
1760 
1761       if (!keep_arguments)
1762 	DECL_ARGUMENTS (decl) = NULL;
1763     }
1764   /* If the node is abstract and needed, then do not clear
1765      DECL_INITIAL of its associated function declaration because it's
1766      needed to emit debug info later.  */
1767   if (!used_as_abstract_origin && DECL_INITIAL (decl))
1768     DECL_INITIAL (decl) = error_mark_node;
1769   release_function_body (decl);
1770   if (lto_file_data)
1771     {
1772       lto_free_function_in_decl_state_for_node (this);
1773       lto_file_data = NULL;
1774     }
1775 }
1776 
1777 /* Remove function from symbol table.  */
1778 
1779 void
1780 cgraph_node::remove (void)
1781 {
1782   if (symtab->ipa_clones_dump_file && symtab->cloned_nodes.contains (this))
1783     fprintf (symtab->ipa_clones_dump_file,
1784 	     "Callgraph removal;%s;%d;%s;%d;%d\n", asm_name (), order,
1785 	     DECL_SOURCE_FILE (decl), DECL_SOURCE_LINE (decl),
1786 	     DECL_SOURCE_COLUMN (decl));
1787 
1788   symtab->call_cgraph_removal_hooks (this);
1789   remove_callers ();
1790   remove_callees ();
1791   ipa_transforms_to_apply.release ();
1792   delete_function_version (function_version ());
1793 
1794   /* Incremental inlining access removed nodes stored in the postorder list.
1795      */
1796   force_output = false;
1797   forced_by_abi = false;
1798   cgraph_node *next = nested;
1799   for (cgraph_node *n = nested; n; n = next)
1800   {
1801     next = n->next_nested;
1802     n->origin = NULL;
1803     n->next_nested = NULL;
1804   }
1805   nested = NULL;
1806   if (origin)
1807     {
1808       cgraph_node **node2 = &origin->nested;
1809 
1810       while (*node2 != this)
1811 	node2 = &(*node2)->next_nested;
1812       *node2 = next_nested;
1813     }
1814   unregister ();
1815   if (prev_sibling_clone)
1816     prev_sibling_clone->next_sibling_clone = next_sibling_clone;
1817   else if (clone_of)
1818     clone_of->clones = next_sibling_clone;
1819   if (next_sibling_clone)
1820     next_sibling_clone->prev_sibling_clone = prev_sibling_clone;
1821   if (clones)
1822     {
1823       cgraph_node *n, *next;
1824 
1825       if (clone_of)
1826         {
1827 	  for (n = clones; n->next_sibling_clone; n = n->next_sibling_clone)
1828 	    n->clone_of = clone_of;
1829 	  n->clone_of = clone_of;
1830 	  n->next_sibling_clone = clone_of->clones;
1831 	  if (clone_of->clones)
1832 	    clone_of->clones->prev_sibling_clone = n;
1833 	  clone_of->clones = clones;
1834 	}
1835       else
1836         {
1837 	  /* We are removing node with clones.  This makes clones inconsistent,
1838 	     but assume they will be removed subsequently and just keep clone
1839 	     tree intact.  This can happen in unreachable function removal since
1840 	     we remove unreachable functions in random order, not by bottom-up
1841 	     walk of clone trees.  */
1842 	  for (n = clones; n; n = next)
1843 	    {
1844 	       next = n->next_sibling_clone;
1845 	       n->next_sibling_clone = NULL;
1846 	       n->prev_sibling_clone = NULL;
1847 	       n->clone_of = NULL;
1848 	    }
1849 	}
1850     }
1851 
1852   /* While all the clones are removed after being proceeded, the function
1853      itself is kept in the cgraph even after it is compiled.  Check whether
1854      we are done with this body and reclaim it proactively if this is the case.
1855      */
1856   if (symtab->state != LTO_STREAMING)
1857     {
1858       cgraph_node *n = cgraph_node::get (decl);
1859       if (!n
1860 	  || (!n->clones && !n->clone_of && !n->global.inlined_to
1861 	      && ((symtab->global_info_ready || in_lto_p)
1862 		  && (TREE_ASM_WRITTEN (n->decl)
1863 		      || DECL_EXTERNAL (n->decl)
1864 		      || !n->analyzed
1865 		      || (!flag_wpa && n->in_other_partition)))))
1866 	release_body ();
1867     }
1868   else
1869     {
1870       lto_free_function_in_decl_state_for_node (this);
1871       lto_file_data = NULL;
1872     }
1873 
1874   decl = NULL;
1875   if (call_site_hash)
1876     {
1877       call_site_hash->empty ();
1878       call_site_hash = NULL;
1879     }
1880 
1881   symtab->release_symbol (this);
1882 }
1883 
1884 /* Likewise indicate that a node is having address taken.  */
1885 
1886 void
1887 cgraph_node::mark_address_taken (void)
1888 {
1889   /* Indirect inlining can figure out that all uses of the address are
1890      inlined.  */
1891   if (global.inlined_to)
1892     {
1893       gcc_assert (cfun->after_inlining);
1894       gcc_assert (callers->indirect_inlining_edge);
1895       return;
1896     }
1897   /* FIXME: address_taken flag is used both as a shortcut for testing whether
1898      IPA_REF_ADDR reference exists (and thus it should be set on node
1899      representing alias we take address of) and as a test whether address
1900      of the object was taken (and thus it should be set on node alias is
1901      referring to).  We should remove the first use and the remove the
1902      following set.  */
1903   address_taken = 1;
1904   cgraph_node *node = ultimate_alias_target ();
1905   node->address_taken = 1;
1906 }
1907 
1908 /* Return local info for the compiled function.  */
1909 
1910 cgraph_local_info *
1911 cgraph_node::local_info (tree decl)
1912 {
1913   gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
1914   cgraph_node *node = get (decl);
1915   if (!node)
1916     return NULL;
1917   return &node->ultimate_alias_target ()->local;
1918 }
1919 
1920 /* Return local info for the compiled function.  */
1921 
1922 cgraph_rtl_info *
1923 cgraph_node::rtl_info (tree decl)
1924 {
1925   gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
1926   cgraph_node *node = get (decl);
1927   if (!node)
1928     return NULL;
1929   enum availability avail;
1930   node = node->ultimate_alias_target (&avail);
1931   if (decl != current_function_decl
1932       && (avail < AVAIL_AVAILABLE
1933 	  || (node->decl != current_function_decl
1934 	      && !TREE_ASM_WRITTEN (node->decl))))
1935     return NULL;
1936   /* Allocate if it doesn't exist.  */
1937   if (node->rtl == NULL)
1938     node->rtl = ggc_cleared_alloc<cgraph_rtl_info> ();
1939   return node->rtl;
1940 }
1941 
1942 /* Return a string describing the failure REASON.  */
1943 
1944 const char*
1945 cgraph_inline_failed_string (cgraph_inline_failed_t reason)
1946 {
1947 #undef DEFCIFCODE
1948 #define DEFCIFCODE(code, type, string)	string,
1949 
1950   static const char *cif_string_table[CIF_N_REASONS] = {
1951 #include "cif-code.def"
1952   };
1953 
1954   /* Signedness of an enum type is implementation defined, so cast it
1955      to unsigned before testing. */
1956   gcc_assert ((unsigned) reason < CIF_N_REASONS);
1957   return cif_string_table[reason];
1958 }
1959 
1960 /* Return a type describing the failure REASON.  */
1961 
1962 cgraph_inline_failed_type_t
1963 cgraph_inline_failed_type (cgraph_inline_failed_t reason)
1964 {
1965 #undef DEFCIFCODE
1966 #define DEFCIFCODE(code, type, string)	type,
1967 
1968   static cgraph_inline_failed_type_t cif_type_table[CIF_N_REASONS] = {
1969 #include "cif-code.def"
1970   };
1971 
1972   /* Signedness of an enum type is implementation defined, so cast it
1973      to unsigned before testing. */
1974   gcc_assert ((unsigned) reason < CIF_N_REASONS);
1975   return cif_type_table[reason];
1976 }
1977 
1978 /* Names used to print out the availability enum.  */
1979 const char * const cgraph_availability_names[] =
1980   {"unset", "not_available", "overwritable", "available", "local"};
1981 
1982 /* Output flags of edge to a file F.  */
1983 
1984 void
1985 cgraph_edge::dump_edge_flags (FILE *f)
1986 {
1987   if (speculative)
1988     fprintf (f, "(speculative) ");
1989   if (!inline_failed)
1990     fprintf (f, "(inlined) ");
1991   if (call_stmt_cannot_inline_p)
1992     fprintf (f, "(call_stmt_cannot_inline_p) ");
1993   if (indirect_inlining_edge)
1994     fprintf (f, "(indirect_inlining) ");
1995   if (count.initialized_p ())
1996     {
1997       fprintf (f, "(");
1998       count.dump (f);
1999       fprintf (f, ",");
2000       fprintf (f, "%.2f per call) ", sreal_frequency ().to_double ());
2001     }
2002   if (can_throw_external)
2003     fprintf (f, "(can throw external) ");
2004 }
2005 
2006 /* Dump call graph node to file F.  */
2007 
2008 void
2009 cgraph_node::dump (FILE *f)
2010 {
2011   cgraph_edge *edge;
2012 
2013   dump_base (f);
2014 
2015   if (global.inlined_to)
2016     fprintf (f, "  Function %s is inline copy in %s\n",
2017 	     dump_name (),
2018 	     global.inlined_to->dump_name ());
2019   if (clone_of)
2020     fprintf (f, "  Clone of %s\n", clone_of->dump_asm_name ());
2021   if (symtab->function_flags_ready)
2022     fprintf (f, "  Availability: %s\n",
2023 	     cgraph_availability_names [get_availability ()]);
2024 
2025   if (profile_id)
2026     fprintf (f, "  Profile id: %i\n",
2027 	     profile_id);
2028   cgraph_function_version_info *vi = function_version ();
2029   if (vi != NULL)
2030     {
2031       fprintf (f, "  Version info: ");
2032       if (vi->prev != NULL)
2033 	{
2034 	  fprintf (f, "prev: ");
2035 	  fprintf (f, "%s ", vi->prev->this_node->dump_asm_name ());
2036 	}
2037       if (vi->next != NULL)
2038 	{
2039 	  fprintf (f, "next: ");
2040 	  fprintf (f, "%s ", vi->next->this_node->dump_asm_name ());
2041 	}
2042       if (vi->dispatcher_resolver != NULL_TREE)
2043 	fprintf (f, "dispatcher: %s",
2044 		 lang_hooks.decl_printable_name (vi->dispatcher_resolver, 2));
2045 
2046       fprintf (f, "\n");
2047     }
2048   fprintf (f, "  Function flags:");
2049   if (count.initialized_p ())
2050     {
2051       fprintf (f, " count:");
2052       count.dump (f);
2053     }
2054   if (tp_first_run > 0)
2055     fprintf (f, " first_run:%i", tp_first_run);
2056   if (origin)
2057     fprintf (f, " nested in:%s", origin->asm_name ());
2058   if (gimple_has_body_p (decl))
2059     fprintf (f, " body");
2060   if (process)
2061     fprintf (f, " process");
2062   if (local.local)
2063     fprintf (f, " local");
2064   if (local.redefined_extern_inline)
2065     fprintf (f, " redefined_extern_inline");
2066   if (only_called_at_startup)
2067     fprintf (f, " only_called_at_startup");
2068   if (only_called_at_exit)
2069     fprintf (f, " only_called_at_exit");
2070   if (tm_clone)
2071     fprintf (f, " tm_clone");
2072   if (calls_comdat_local)
2073     fprintf (f, " calls_comdat_local");
2074   if (icf_merged)
2075     fprintf (f, " icf_merged");
2076   if (merged_comdat)
2077     fprintf (f, " merged_comdat");
2078   if (split_part)
2079     fprintf (f, " split_part");
2080   if (indirect_call_target)
2081     fprintf (f, " indirect_call_target");
2082   if (nonfreeing_fn)
2083     fprintf (f, " nonfreeing_fn");
2084   if (DECL_STATIC_CONSTRUCTOR (decl))
2085     fprintf (f," static_constructor (priority:%i)", get_init_priority ());
2086   if (DECL_STATIC_DESTRUCTOR (decl))
2087     fprintf (f," static_destructor (priority:%i)", get_fini_priority ());
2088   if (frequency == NODE_FREQUENCY_HOT)
2089     fprintf (f, " hot");
2090   if (frequency == NODE_FREQUENCY_UNLIKELY_EXECUTED)
2091     fprintf (f, " unlikely_executed");
2092   if (frequency == NODE_FREQUENCY_EXECUTED_ONCE)
2093     fprintf (f, " executed_once");
2094   if (opt_for_fn (decl, optimize_size))
2095     fprintf (f, " optimize_size");
2096   if (parallelized_function)
2097     fprintf (f, " parallelized_function");
2098 
2099   fprintf (f, "\n");
2100 
2101   if (thunk.thunk_p)
2102     {
2103       fprintf (f, "  Thunk");
2104       if (thunk.alias)
2105 	fprintf (f, "  of %s (asm:%s)",
2106 		 lang_hooks.decl_printable_name (thunk.alias, 2),
2107 		 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (thunk.alias)));
2108       fprintf (f, " fixed offset %i virtual value %i indirect_offset %i "
2109 		  "has virtual offset %i\n",
2110 	       (int)thunk.fixed_offset,
2111 	       (int)thunk.virtual_value,
2112 	       (int)thunk.indirect_offset,
2113 	       (int)thunk.virtual_offset_p);
2114     }
2115   else if (former_thunk_p ())
2116     fprintf (f, "  Former thunk fixed offset %i virtual value %i "
2117 	     "indirect_offset %i has virtual offset %i\n",
2118 	     (int)thunk.fixed_offset,
2119 	     (int)thunk.virtual_value,
2120 	     (int)thunk.indirect_offset,
2121 	     (int)thunk.virtual_offset_p);
2122   if (alias && thunk.alias
2123       && DECL_P (thunk.alias))
2124     {
2125       fprintf (f, "  Alias of %s",
2126 	       lang_hooks.decl_printable_name (thunk.alias, 2));
2127       if (DECL_ASSEMBLER_NAME_SET_P (thunk.alias))
2128 	fprintf (f, " (asm:%s)",
2129 		 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (thunk.alias)));
2130       fprintf (f, "\n");
2131     }
2132 
2133   fprintf (f, "  Called by: ");
2134 
2135   profile_count sum = profile_count::zero ();
2136   for (edge = callers; edge; edge = edge->next_caller)
2137     {
2138       fprintf (f, "%s ", edge->caller->dump_name ());
2139       edge->dump_edge_flags (f);
2140       if (edge->count.initialized_p ())
2141 	sum += edge->count.ipa ();
2142     }
2143 
2144   fprintf (f, "\n  Calls: ");
2145   for (edge = callees; edge; edge = edge->next_callee)
2146     {
2147       fprintf (f, "%s ", edge->callee->dump_name ());
2148       edge->dump_edge_flags (f);
2149     }
2150   fprintf (f, "\n");
2151 
2152   if (count.ipa ().initialized_p ())
2153     {
2154       bool ok = true;
2155       bool min = false;
2156       ipa_ref *ref;
2157 
2158       FOR_EACH_ALIAS (this, ref)
2159 	if (dyn_cast <cgraph_node *> (ref->referring)->count.initialized_p ())
2160 	  sum += dyn_cast <cgraph_node *> (ref->referring)->count.ipa ();
2161 
2162       if (global.inlined_to
2163 	  || (symtab->state < EXPANSION
2164 	      && ultimate_alias_target () == this && only_called_directly_p ()))
2165 	ok = !count.ipa ().differs_from_p (sum);
2166       else if (count.ipa () > profile_count::from_gcov_type (100)
2167 	       && count.ipa () < sum.apply_scale (99, 100))
2168 	ok = false, min = true;
2169       if (!ok)
2170 	{
2171 	  fprintf (f, "   Invalid sum of caller counts ");
2172 	  sum.dump (f);
2173 	  if (min)
2174 	    fprintf (f, ", should be at most ");
2175 	  else
2176 	    fprintf (f, ", should be ");
2177 	  count.ipa ().dump (f);
2178 	  fprintf (f, "\n");
2179 	}
2180     }
2181 
2182   for (edge = indirect_calls; edge; edge = edge->next_callee)
2183     {
2184       if (edge->indirect_info->polymorphic)
2185 	{
2186           fprintf (f, "   Polymorphic indirect call of type ");
2187 	  print_generic_expr (f, edge->indirect_info->otr_type, TDF_SLIM);
2188 	  fprintf (f, " token:%i", (int) edge->indirect_info->otr_token);
2189 	}
2190       else
2191         fprintf (f, "   Indirect call");
2192       edge->dump_edge_flags (f);
2193       if (edge->indirect_info->param_index != -1)
2194 	{
2195 	  fprintf (f, " of param:%i", edge->indirect_info->param_index);
2196 	  if (edge->indirect_info->agg_contents)
2197 	   fprintf (f, " loaded from %s %s at offset %i",
2198 		    edge->indirect_info->member_ptr ? "member ptr" : "aggregate",
2199 		    edge->indirect_info->by_ref ? "passed by reference":"",
2200 		    (int)edge->indirect_info->offset);
2201 	  if (edge->indirect_info->vptr_changed)
2202 	    fprintf (f, " (vptr maybe changed)");
2203 	}
2204       fprintf (f, "\n");
2205       if (edge->indirect_info->polymorphic)
2206 	edge->indirect_info->context.dump (f);
2207     }
2208 }
2209 
2210 /* Dump call graph node NODE to stderr.  */
2211 
2212 DEBUG_FUNCTION void
2213 cgraph_node::debug (void)
2214 {
2215   dump (stderr);
2216 }
2217 
2218 /* Dump the callgraph to file F.  */
2219 
2220 void
2221 cgraph_node::dump_cgraph (FILE *f)
2222 {
2223   cgraph_node *node;
2224 
2225   fprintf (f, "callgraph:\n\n");
2226   FOR_EACH_FUNCTION (node)
2227     node->dump (f);
2228 }
2229 
2230 /* Return true when the DECL can possibly be inlined.  */
2231 
2232 bool
2233 cgraph_function_possibly_inlined_p (tree decl)
2234 {
2235   if (!symtab->global_info_ready)
2236     return !DECL_UNINLINABLE (decl);
2237   return DECL_POSSIBLY_INLINED (decl);
2238 }
2239 
2240 /* cgraph_node is no longer nested function; update cgraph accordingly.  */
2241 void
2242 cgraph_node::unnest (void)
2243 {
2244   cgraph_node **node2 = &origin->nested;
2245   gcc_assert (origin);
2246 
2247   while (*node2 != this)
2248     node2 = &(*node2)->next_nested;
2249   *node2 = next_nested;
2250   origin = NULL;
2251 }
2252 
2253 /* Return function availability.  See cgraph.h for description of individual
2254    return values.  */
2255 enum availability
2256 cgraph_node::get_availability (symtab_node *ref)
2257 {
2258   if (ref)
2259     {
2260       cgraph_node *cref = dyn_cast <cgraph_node *> (ref);
2261       if (cref)
2262 	ref = cref->global.inlined_to;
2263     }
2264   enum availability avail;
2265   if (!analyzed)
2266     avail = AVAIL_NOT_AVAILABLE;
2267   else if (local.local)
2268     avail = AVAIL_LOCAL;
2269   else if (global.inlined_to)
2270     avail = AVAIL_AVAILABLE;
2271   else if (transparent_alias)
2272     ultimate_alias_target (&avail, ref);
2273   else if (ifunc_resolver
2274 	   || lookup_attribute ("noipa", DECL_ATTRIBUTES (decl)))
2275     avail = AVAIL_INTERPOSABLE;
2276   else if (!externally_visible)
2277     avail = AVAIL_AVAILABLE;
2278   /* If this is a reference from symbol itself and there are no aliases, we
2279      may be sure that the symbol was not interposed by something else because
2280      the symbol itself would be unreachable otherwise.
2281 
2282      Also comdat groups are always resolved in groups.  */
2283   else if ((this == ref && !has_aliases_p ())
2284            || (ref && get_comdat_group ()
2285                && get_comdat_group () == ref->get_comdat_group ()))
2286     avail = AVAIL_AVAILABLE;
2287   /* Inline functions are safe to be analyzed even if their symbol can
2288      be overwritten at runtime.  It is not meaningful to enforce any sane
2289      behavior on replacing inline function by different body.  */
2290   else if (DECL_DECLARED_INLINE_P (decl))
2291     avail = AVAIL_AVAILABLE;
2292 
2293   /* If the function can be overwritten, return OVERWRITABLE.  Take
2294      care at least of two notable extensions - the COMDAT functions
2295      used to share template instantiations in C++ (this is symmetric
2296      to code cp_cannot_inline_tree_fn and probably shall be shared and
2297      the inlinability hooks completely eliminated).  */
2298 
2299   else if (decl_replaceable_p (decl) && !DECL_EXTERNAL (decl))
2300     avail = AVAIL_INTERPOSABLE;
2301   else avail = AVAIL_AVAILABLE;
2302 
2303   return avail;
2304 }
2305 
2306 /* Worker for cgraph_node_can_be_local_p.  */
2307 static bool
2308 cgraph_node_cannot_be_local_p_1 (cgraph_node *node, void *)
2309 {
2310   return !(!node->force_output
2311 	   && ((DECL_COMDAT (node->decl)
2312 		&& !node->forced_by_abi
2313 		&& !node->used_from_object_file_p ()
2314 		&& !node->same_comdat_group)
2315 	       || !node->externally_visible));
2316 }
2317 
2318 /* Return true if cgraph_node can be made local for API change.
2319    Extern inline functions and C++ COMDAT functions can be made local
2320    at the expense of possible code size growth if function is used in multiple
2321    compilation units.  */
2322 bool
2323 cgraph_node::can_be_local_p (void)
2324 {
2325   return (!address_taken
2326 	  && !call_for_symbol_thunks_and_aliases (cgraph_node_cannot_be_local_p_1,
2327 						NULL, true));
2328 }
2329 
2330 /* Call callback on cgraph_node, thunks and aliases associated to cgraph_node.
2331    When INCLUDE_OVERWRITABLE is false, overwritable symbols are
2332    skipped.  When EXCLUDE_VIRTUAL_THUNKS is true, virtual thunks are
2333    skipped.  */
2334 bool
2335 cgraph_node::call_for_symbol_thunks_and_aliases (bool (*callback)
2336 						   (cgraph_node *, void *),
2337 						 void *data,
2338 						 bool include_overwritable,
2339 						 bool exclude_virtual_thunks)
2340 {
2341   cgraph_edge *e;
2342   ipa_ref *ref;
2343   enum availability avail = AVAIL_AVAILABLE;
2344 
2345   if (include_overwritable
2346       || (avail = get_availability ()) > AVAIL_INTERPOSABLE)
2347     {
2348       if (callback (this, data))
2349         return true;
2350     }
2351   FOR_EACH_ALIAS (this, ref)
2352     {
2353       cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring);
2354       if (include_overwritable
2355 	  || alias->get_availability () > AVAIL_INTERPOSABLE)
2356 	if (alias->call_for_symbol_thunks_and_aliases (callback, data,
2357 						     include_overwritable,
2358 						     exclude_virtual_thunks))
2359 	  return true;
2360     }
2361   if (avail <= AVAIL_INTERPOSABLE)
2362     return false;
2363   for (e = callers; e; e = e->next_caller)
2364     if (e->caller->thunk.thunk_p
2365 	&& (include_overwritable
2366 	    || e->caller->get_availability () > AVAIL_INTERPOSABLE)
2367 	&& !(exclude_virtual_thunks
2368 	     && e->caller->thunk.virtual_offset_p))
2369       if (e->caller->call_for_symbol_thunks_and_aliases (callback, data,
2370 						       include_overwritable,
2371 						       exclude_virtual_thunks))
2372 	return true;
2373 
2374   return false;
2375 }
2376 
2377 /* Worker to bring NODE local.  */
2378 
2379 bool
2380 cgraph_node::make_local (cgraph_node *node, void *)
2381 {
2382   gcc_checking_assert (node->can_be_local_p ());
2383   if (DECL_COMDAT (node->decl) || DECL_EXTERNAL (node->decl))
2384     {
2385       node->make_decl_local ();
2386       node->set_section (NULL);
2387       node->set_comdat_group (NULL);
2388       node->externally_visible = false;
2389       node->forced_by_abi = false;
2390       node->local.local = true;
2391       node->set_section (NULL);
2392       node->unique_name = ((node->resolution == LDPR_PREVAILING_DEF_IRONLY
2393 			   || node->resolution == LDPR_PREVAILING_DEF_IRONLY_EXP)
2394 			   && !flag_incremental_link);
2395       node->resolution = LDPR_PREVAILING_DEF_IRONLY;
2396       gcc_assert (node->get_availability () == AVAIL_LOCAL);
2397     }
2398   return false;
2399 }
2400 
2401 /* Bring cgraph node local.  */
2402 
2403 void
2404 cgraph_node::make_local (void)
2405 {
2406   call_for_symbol_thunks_and_aliases (cgraph_node::make_local, NULL, true);
2407 }
2408 
2409 /* Worker to set nothrow flag.  */
2410 
2411 static void
2412 set_nothrow_flag_1 (cgraph_node *node, bool nothrow, bool non_call,
2413 		    bool *changed)
2414 {
2415   cgraph_edge *e;
2416 
2417   if (nothrow && !TREE_NOTHROW (node->decl))
2418     {
2419       /* With non-call exceptions we can't say for sure if other function body
2420 	 was not possibly optimized to stil throw.  */
2421       if (!non_call || node->binds_to_current_def_p ())
2422 	{
2423 	  TREE_NOTHROW (node->decl) = true;
2424 	  *changed = true;
2425 	  for (e = node->callers; e; e = e->next_caller)
2426 	    e->can_throw_external = false;
2427 	}
2428     }
2429   else if (!nothrow && TREE_NOTHROW (node->decl))
2430     {
2431       TREE_NOTHROW (node->decl) = false;
2432       *changed = true;
2433     }
2434   ipa_ref *ref;
2435   FOR_EACH_ALIAS (node, ref)
2436     {
2437       cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring);
2438       if (!nothrow || alias->get_availability () > AVAIL_INTERPOSABLE)
2439 	set_nothrow_flag_1 (alias, nothrow, non_call, changed);
2440     }
2441   for (cgraph_edge *e = node->callers; e; e = e->next_caller)
2442     if (e->caller->thunk.thunk_p
2443 	&& (!nothrow || e->caller->get_availability () > AVAIL_INTERPOSABLE))
2444       set_nothrow_flag_1 (e->caller, nothrow, non_call, changed);
2445 }
2446 
2447 /* Set TREE_NOTHROW on NODE's decl and on aliases of NODE
2448    if any to NOTHROW.  */
2449 
2450 bool
2451 cgraph_node::set_nothrow_flag (bool nothrow)
2452 {
2453   bool changed = false;
2454   bool non_call = opt_for_fn (decl, flag_non_call_exceptions);
2455 
2456   if (!nothrow || get_availability () > AVAIL_INTERPOSABLE)
2457     set_nothrow_flag_1 (this, nothrow, non_call, &changed);
2458   else
2459     {
2460       ipa_ref *ref;
2461 
2462       FOR_EACH_ALIAS (this, ref)
2463 	{
2464 	  cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring);
2465 	  if (!nothrow || alias->get_availability () > AVAIL_INTERPOSABLE)
2466 	    set_nothrow_flag_1 (alias, nothrow, non_call, &changed);
2467 	}
2468     }
2469   return changed;
2470 }
2471 
2472 /* Worker to set malloc flag.  */
2473 static void
2474 set_malloc_flag_1 (cgraph_node *node, bool malloc_p, bool *changed)
2475 {
2476   if (malloc_p && !DECL_IS_MALLOC (node->decl))
2477     {
2478       DECL_IS_MALLOC (node->decl) = true;
2479       *changed = true;
2480     }
2481 
2482   ipa_ref *ref;
2483   FOR_EACH_ALIAS (node, ref)
2484     {
2485       cgraph_node *alias = dyn_cast<cgraph_node *> (ref->referring);
2486       if (!malloc_p || alias->get_availability () > AVAIL_INTERPOSABLE)
2487 	set_malloc_flag_1 (alias, malloc_p, changed);
2488     }
2489 
2490   for (cgraph_edge *e = node->callers; e; e = e->next_caller)
2491     if (e->caller->thunk.thunk_p
2492 	&& (!malloc_p || e->caller->get_availability () > AVAIL_INTERPOSABLE))
2493       set_malloc_flag_1 (e->caller, malloc_p, changed);
2494 }
2495 
2496 /* Set DECL_IS_MALLOC on NODE's decl and on NODE's aliases if any.  */
2497 
2498 bool
2499 cgraph_node::set_malloc_flag (bool malloc_p)
2500 {
2501   bool changed = false;
2502 
2503   if (!malloc_p || get_availability () > AVAIL_INTERPOSABLE)
2504     set_malloc_flag_1 (this, malloc_p, &changed);
2505   else
2506     {
2507       ipa_ref *ref;
2508 
2509       FOR_EACH_ALIAS (this, ref)
2510 	{
2511 	  cgraph_node *alias = dyn_cast<cgraph_node *> (ref->referring);
2512 	  if (!malloc_p || alias->get_availability () > AVAIL_INTERPOSABLE)
2513 	    set_malloc_flag_1 (alias, malloc_p, &changed);
2514 	}
2515     }
2516   return changed;
2517 }
2518 
2519 /* Worker to set_const_flag.  */
2520 
2521 static void
2522 set_const_flag_1 (cgraph_node *node, bool set_const, bool looping,
2523 		  bool *changed)
2524 {
2525   /* Static constructors and destructors without a side effect can be
2526      optimized out.  */
2527   if (set_const && !looping)
2528     {
2529       if (DECL_STATIC_CONSTRUCTOR (node->decl))
2530 	{
2531 	  DECL_STATIC_CONSTRUCTOR (node->decl) = 0;
2532 	  *changed = true;
2533 	}
2534       if (DECL_STATIC_DESTRUCTOR (node->decl))
2535 	{
2536 	  DECL_STATIC_DESTRUCTOR (node->decl) = 0;
2537 	  *changed = true;
2538 	}
2539     }
2540   if (!set_const)
2541     {
2542       if (TREE_READONLY (node->decl))
2543 	{
2544           TREE_READONLY (node->decl) = 0;
2545           DECL_LOOPING_CONST_OR_PURE_P (node->decl) = false;
2546 	  *changed = true;
2547 	}
2548     }
2549   else
2550     {
2551       /* Consider function:
2552 
2553 	 bool a(int *p)
2554 	 {
2555 	   return *p==*p;
2556 	 }
2557 
2558 	 During early optimization we will turn this into:
2559 
2560 	 bool a(int *p)
2561 	 {
2562 	   return true;
2563 	 }
2564 
2565 	 Now if this function will be detected as CONST however when interposed
2566 	 it may end up being just pure.  We always must assume the worst
2567 	 scenario here.  */
2568       if (TREE_READONLY (node->decl))
2569 	{
2570 	  if (!looping && DECL_LOOPING_CONST_OR_PURE_P (node->decl))
2571 	    {
2572               DECL_LOOPING_CONST_OR_PURE_P (node->decl) = false;
2573 	      *changed = true;
2574 	    }
2575 	}
2576       else if (node->binds_to_current_def_p ())
2577 	{
2578 	  TREE_READONLY (node->decl) = true;
2579           DECL_LOOPING_CONST_OR_PURE_P (node->decl) = looping;
2580 	  DECL_PURE_P (node->decl) = false;
2581 	  *changed = true;
2582 	}
2583       else
2584 	{
2585 	  if (dump_file && (dump_flags & TDF_DETAILS))
2586 	    fprintf (dump_file, "Dropping state to PURE because function does "
2587 		     "not bind to current def.\n");
2588 	  if (!DECL_PURE_P (node->decl))
2589 	    {
2590 	      DECL_PURE_P (node->decl) = true;
2591               DECL_LOOPING_CONST_OR_PURE_P (node->decl) = looping;
2592 	      *changed = true;
2593 	    }
2594 	  else if (!looping && DECL_LOOPING_CONST_OR_PURE_P (node->decl))
2595 	    {
2596               DECL_LOOPING_CONST_OR_PURE_P (node->decl) = false;
2597 	      *changed = true;
2598 	    }
2599 	}
2600     }
2601 
2602   ipa_ref *ref;
2603   FOR_EACH_ALIAS (node, ref)
2604     {
2605       cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring);
2606       if (!set_const || alias->get_availability () > AVAIL_INTERPOSABLE)
2607 	set_const_flag_1 (alias, set_const, looping, changed);
2608     }
2609   for (cgraph_edge *e = node->callers; e; e = e->next_caller)
2610     if (e->caller->thunk.thunk_p
2611 	&& (!set_const || e->caller->get_availability () > AVAIL_INTERPOSABLE))
2612       {
2613 	/* Virtual thunks access virtual offset in the vtable, so they can
2614 	   only be pure, never const.  */
2615         if (set_const
2616 	    && (e->caller->thunk.virtual_offset_p
2617 	        || !node->binds_to_current_def_p (e->caller)))
2618 	  *changed |= e->caller->set_pure_flag (true, looping);
2619 	else
2620 	  set_const_flag_1 (e->caller, set_const, looping, changed);
2621       }
2622 }
2623 
2624 /* If SET_CONST is true, mark function, aliases and thunks to be ECF_CONST.
2625    If SET_CONST if false, clear the flag.
2626 
2627    When setting the flag be careful about possible interposition and
2628    do not set the flag for functions that can be interposet and set pure
2629    flag for functions that can bind to other definition.
2630 
2631    Return true if any change was done. */
2632 
2633 bool
2634 cgraph_node::set_const_flag (bool set_const, bool looping)
2635 {
2636   bool changed = false;
2637   if (!set_const || get_availability () > AVAIL_INTERPOSABLE)
2638     set_const_flag_1 (this, set_const, looping, &changed);
2639   else
2640     {
2641       ipa_ref *ref;
2642 
2643       FOR_EACH_ALIAS (this, ref)
2644 	{
2645 	  cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring);
2646 	  if (!set_const || alias->get_availability () > AVAIL_INTERPOSABLE)
2647 	    set_const_flag_1 (alias, set_const, looping, &changed);
2648 	}
2649     }
2650   return changed;
2651 }
2652 
2653 /* Info used by set_pure_flag_1.  */
2654 
2655 struct set_pure_flag_info
2656 {
2657   bool pure;
2658   bool looping;
2659   bool changed;
2660 };
2661 
2662 /* Worker to set_pure_flag.  */
2663 
2664 static bool
2665 set_pure_flag_1 (cgraph_node *node, void *data)
2666 {
2667   struct set_pure_flag_info *info = (struct set_pure_flag_info *)data;
2668   /* Static constructors and destructors without a side effect can be
2669      optimized out.  */
2670   if (info->pure && !info->looping)
2671     {
2672       if (DECL_STATIC_CONSTRUCTOR (node->decl))
2673 	{
2674 	  DECL_STATIC_CONSTRUCTOR (node->decl) = 0;
2675 	  info->changed = true;
2676 	}
2677       if (DECL_STATIC_DESTRUCTOR (node->decl))
2678 	{
2679 	  DECL_STATIC_DESTRUCTOR (node->decl) = 0;
2680 	  info->changed = true;
2681 	}
2682     }
2683   if (info->pure)
2684     {
2685       if (!DECL_PURE_P (node->decl) && !TREE_READONLY (node->decl))
2686 	{
2687           DECL_PURE_P (node->decl) = true;
2688           DECL_LOOPING_CONST_OR_PURE_P (node->decl) = info->looping;
2689 	  info->changed = true;
2690 	}
2691       else if (DECL_LOOPING_CONST_OR_PURE_P (node->decl)
2692 	       && !info->looping)
2693 	{
2694           DECL_LOOPING_CONST_OR_PURE_P (node->decl) = false;
2695 	  info->changed = true;
2696 	}
2697     }
2698   else
2699     {
2700       if (DECL_PURE_P (node->decl))
2701 	{
2702           DECL_PURE_P (node->decl) = false;
2703           DECL_LOOPING_CONST_OR_PURE_P (node->decl) = false;
2704 	  info->changed = true;
2705 	}
2706     }
2707   return false;
2708 }
2709 
2710 /* Set DECL_PURE_P on cgraph_node's decl and on aliases of the node
2711    if any to PURE.
2712 
2713    When setting the flag, be careful about possible interposition.
2714    Return true if any change was done. */
2715 
2716 bool
2717 cgraph_node::set_pure_flag (bool pure, bool looping)
2718 {
2719   struct set_pure_flag_info info = {pure, looping, false};
2720   if (!pure)
2721     looping = false;
2722   call_for_symbol_thunks_and_aliases (set_pure_flag_1, &info, !pure, true);
2723   return info.changed;
2724 }
2725 
2726 /* Return true when cgraph_node cannot return or throw and thus
2727    it is safe to ignore its side effects for IPA analysis.  */
2728 
2729 bool
2730 cgraph_node::cannot_return_p (void)
2731 {
2732   int flags = flags_from_decl_or_type (decl);
2733   if (!opt_for_fn (decl, flag_exceptions))
2734     return (flags & ECF_NORETURN) != 0;
2735   else
2736     return ((flags & (ECF_NORETURN | ECF_NOTHROW))
2737 	     == (ECF_NORETURN | ECF_NOTHROW));
2738 }
2739 
2740 /* Return true when call of edge cannot lead to return from caller
2741    and thus it is safe to ignore its side effects for IPA analysis
2742    when computing side effects of the caller.
2743    FIXME: We could actually mark all edges that have no reaching
2744    patch to the exit block or throw to get better results.  */
2745 bool
2746 cgraph_edge::cannot_lead_to_return_p (void)
2747 {
2748   if (caller->cannot_return_p ())
2749     return true;
2750   if (indirect_unknown_callee)
2751     {
2752       int flags = indirect_info->ecf_flags;
2753       if (!opt_for_fn (caller->decl, flag_exceptions))
2754 	return (flags & ECF_NORETURN) != 0;
2755       else
2756 	return ((flags & (ECF_NORETURN | ECF_NOTHROW))
2757 		 == (ECF_NORETURN | ECF_NOTHROW));
2758     }
2759   else
2760     return callee->cannot_return_p ();
2761 }
2762 
2763 /* Return true if the call can be hot.  */
2764 
2765 bool
2766 cgraph_edge::maybe_hot_p (void)
2767 {
2768   if (!maybe_hot_count_p (NULL, count.ipa ()))
2769     return false;
2770   if (caller->frequency == NODE_FREQUENCY_UNLIKELY_EXECUTED
2771       || (callee
2772 	  && callee->frequency == NODE_FREQUENCY_UNLIKELY_EXECUTED))
2773     return false;
2774   if (caller->frequency > NODE_FREQUENCY_UNLIKELY_EXECUTED
2775       && (callee
2776 	  && callee->frequency <= NODE_FREQUENCY_EXECUTED_ONCE))
2777     return false;
2778   if (opt_for_fn (caller->decl, optimize_size))
2779     return false;
2780   if (caller->frequency == NODE_FREQUENCY_HOT)
2781     return true;
2782   /* If profile is now known yet, be conservative.
2783      FIXME: this predicate is used by early inliner and can do better there.  */
2784   if (symtab->state < IPA_SSA)
2785     return true;
2786   if (caller->frequency == NODE_FREQUENCY_EXECUTED_ONCE
2787       && sreal_frequency () * 2 < 3)
2788     return false;
2789   if (PARAM_VALUE (HOT_BB_FREQUENCY_FRACTION) == 0
2790       || sreal_frequency () * PARAM_VALUE (HOT_BB_FREQUENCY_FRACTION) <= 1)
2791     return false;
2792   return true;
2793 }
2794 
2795 /* Worker for cgraph_can_remove_if_no_direct_calls_p.  */
2796 
2797 static bool
2798 nonremovable_p (cgraph_node *node, void *)
2799 {
2800   return !node->can_remove_if_no_direct_calls_and_refs_p ();
2801 }
2802 
2803 /* Return true if whole comdat group can be removed if there are no direct
2804    calls to THIS.  */
2805 
2806 bool
2807 cgraph_node::can_remove_if_no_direct_calls_p (bool will_inline)
2808 {
2809   struct ipa_ref *ref;
2810 
2811   /* For local symbols or non-comdat group it is the same as
2812      can_remove_if_no_direct_calls_p.  */
2813   if (!externally_visible || !same_comdat_group)
2814     {
2815       if (DECL_EXTERNAL (decl))
2816 	return true;
2817       if (address_taken)
2818 	return false;
2819       return !call_for_symbol_and_aliases (nonremovable_p, NULL, true);
2820     }
2821 
2822   if (will_inline && address_taken)
2823     return false;
2824 
2825   /* Otheriwse check if we can remove the symbol itself and then verify
2826      that only uses of the comdat groups are direct call to THIS
2827      or its aliases.   */
2828   if (!can_remove_if_no_direct_calls_and_refs_p ())
2829     return false;
2830 
2831   /* Check that all refs come from within the comdat group.  */
2832   for (int i = 0; iterate_referring (i, ref); i++)
2833     if (ref->referring->get_comdat_group () != get_comdat_group ())
2834       return false;
2835 
2836   struct cgraph_node *target = ultimate_alias_target ();
2837   for (cgraph_node *next = dyn_cast<cgraph_node *> (same_comdat_group);
2838        next != this; next = dyn_cast<cgraph_node *> (next->same_comdat_group))
2839     {
2840       if (!externally_visible)
2841 	continue;
2842       if (!next->alias
2843 	  && !next->can_remove_if_no_direct_calls_and_refs_p ())
2844 	return false;
2845 
2846       /* If we see different symbol than THIS, be sure to check calls.  */
2847       if (next->ultimate_alias_target () != target)
2848 	for (cgraph_edge *e = next->callers; e; e = e->next_caller)
2849 	  if (e->caller->get_comdat_group () != get_comdat_group ()
2850 	      || will_inline)
2851 	    return false;
2852 
2853       /* If function is not being inlined, we care only about
2854 	 references outside of the comdat group.  */
2855       if (!will_inline)
2856         for (int i = 0; next->iterate_referring (i, ref); i++)
2857 	  if (ref->referring->get_comdat_group () != get_comdat_group ())
2858 	    return false;
2859     }
2860   return true;
2861 }
2862 
2863 /* Return true when function cgraph_node can be expected to be removed
2864    from program when direct calls in this compilation unit are removed.
2865 
2866    As a special case COMDAT functions are
2867    cgraph_can_remove_if_no_direct_calls_p while the are not
2868    cgraph_only_called_directly_p (it is possible they are called from other
2869    unit)
2870 
2871    This function behaves as cgraph_only_called_directly_p because eliminating
2872    all uses of COMDAT function does not make it necessarily disappear from
2873    the program unless we are compiling whole program or we do LTO.  In this
2874    case we know we win since dynamic linking will not really discard the
2875    linkonce section.  */
2876 
2877 bool
2878 cgraph_node::will_be_removed_from_program_if_no_direct_calls_p
2879 	 (bool will_inline)
2880 {
2881   gcc_assert (!global.inlined_to);
2882   if (DECL_EXTERNAL (decl))
2883     return true;
2884 
2885   if (!in_lto_p && !flag_whole_program)
2886     {
2887       /* If the symbol is in comdat group, we need to verify that whole comdat
2888 	 group becomes unreachable.  Technically we could skip references from
2889 	 within the group, too.  */
2890       if (!only_called_directly_p ())
2891 	return false;
2892       if (same_comdat_group && externally_visible)
2893 	{
2894 	  struct cgraph_node *target = ultimate_alias_target ();
2895 
2896 	  if (will_inline && address_taken)
2897 	    return true;
2898 	  for (cgraph_node *next = dyn_cast<cgraph_node *> (same_comdat_group);
2899 	       next != this;
2900 	       next = dyn_cast<cgraph_node *> (next->same_comdat_group))
2901 	    {
2902 	      if (!externally_visible)
2903 		continue;
2904 	      if (!next->alias
2905 		  && !next->only_called_directly_p ())
2906 		return false;
2907 
2908 	      /* If we see different symbol than THIS,
2909 		 be sure to check calls.  */
2910 	      if (next->ultimate_alias_target () != target)
2911 		for (cgraph_edge *e = next->callers; e; e = e->next_caller)
2912 		  if (e->caller->get_comdat_group () != get_comdat_group ()
2913 		      || will_inline)
2914 		    return false;
2915 	    }
2916 	}
2917       return true;
2918     }
2919   else
2920     return can_remove_if_no_direct_calls_p (will_inline);
2921 }
2922 
2923 
2924 /* Worker for cgraph_only_called_directly_p.  */
2925 
2926 static bool
2927 cgraph_not_only_called_directly_p_1 (cgraph_node *node, void *)
2928 {
2929   return !node->only_called_directly_or_aliased_p ();
2930 }
2931 
2932 /* Return true when function cgraph_node and all its aliases are only called
2933    directly.
2934    i.e. it is not externally visible, address was not taken and
2935    it is not used in any other non-standard way.  */
2936 
2937 bool
2938 cgraph_node::only_called_directly_p (void)
2939 {
2940   gcc_assert (ultimate_alias_target () == this);
2941   return !call_for_symbol_and_aliases (cgraph_not_only_called_directly_p_1,
2942 				       NULL, true);
2943 }
2944 
2945 
2946 /* Collect all callers of NODE.  Worker for collect_callers_of_node.  */
2947 
2948 static bool
2949 collect_callers_of_node_1 (cgraph_node *node, void *data)
2950 {
2951   vec<cgraph_edge *> *redirect_callers = (vec<cgraph_edge *> *)data;
2952   cgraph_edge *cs;
2953   enum availability avail;
2954   node->ultimate_alias_target (&avail);
2955 
2956   if (avail > AVAIL_INTERPOSABLE)
2957     for (cs = node->callers; cs != NULL; cs = cs->next_caller)
2958       if (!cs->indirect_inlining_edge
2959 	  && !cs->caller->thunk.thunk_p)
2960         redirect_callers->safe_push (cs);
2961   return false;
2962 }
2963 
2964 /* Collect all callers of cgraph_node and its aliases that are known to lead to
2965    cgraph_node (i.e. are not overwritable).  */
2966 
2967 vec<cgraph_edge *>
2968 cgraph_node::collect_callers (void)
2969 {
2970   vec<cgraph_edge *> redirect_callers = vNULL;
2971   call_for_symbol_thunks_and_aliases (collect_callers_of_node_1,
2972 				    &redirect_callers, false);
2973   return redirect_callers;
2974 }
2975 
2976 
2977 /* Return TRUE if NODE2 a clone of NODE or is equivalent to it.  Return
2978    optimistically true if this cannot be determined.  */
2979 
2980 static bool
2981 clone_of_p (cgraph_node *node, cgraph_node *node2)
2982 {
2983   node = node->ultimate_alias_target ();
2984   node2 = node2->ultimate_alias_target ();
2985 
2986   if (node2->clone_of == node
2987       || node2->former_clone_of == node->decl)
2988     return true;
2989 
2990   if (!node->thunk.thunk_p && !node->former_thunk_p ())
2991     {
2992       while (node2 && node->decl != node2->decl)
2993 	node2 = node2->clone_of;
2994       return node2 != NULL;
2995     }
2996 
2997   /* There are no virtual clones of thunks so check former_clone_of or if we
2998      might have skipped thunks because this adjustments are no longer
2999      necessary.  */
3000   while (node->thunk.thunk_p || node->former_thunk_p ())
3001     {
3002       if (!node->thunk.this_adjusting)
3003 	return false;
3004       /* In case of instrumented expanded thunks, which can have multiple calls
3005 	 in them, we do not know how to continue and just have to be
3006 	 optimistic.  */
3007       if (node->callees->next_callee)
3008 	return true;
3009       node = node->callees->callee->ultimate_alias_target ();
3010 
3011       if (!node2->clone.args_to_skip
3012 	  || !bitmap_bit_p (node2->clone.args_to_skip, 0))
3013 	return false;
3014       if (node2->former_clone_of == node->decl)
3015 	return true;
3016 
3017       cgraph_node *n2 = node2;
3018       while (n2 && node->decl != n2->decl)
3019 	n2 = n2->clone_of;
3020       if (n2)
3021 	return true;
3022     }
3023 
3024   return false;
3025 }
3026 
3027 /* Verify edge count and frequency.  */
3028 
3029 bool
3030 cgraph_edge::verify_count ()
3031 {
3032   bool error_found = false;
3033   if (!count.verify ())
3034     {
3035       error ("caller edge count invalid");
3036       error_found = true;
3037     }
3038   return error_found;
3039 }
3040 
3041 /* Switch to THIS_CFUN if needed and print STMT to stderr.  */
3042 static void
3043 cgraph_debug_gimple_stmt (function *this_cfun, gimple *stmt)
3044 {
3045   bool fndecl_was_null = false;
3046   /* debug_gimple_stmt needs correct cfun */
3047   if (cfun != this_cfun)
3048     set_cfun (this_cfun);
3049   /* ...and an actual current_function_decl */
3050   if (!current_function_decl)
3051     {
3052       current_function_decl = this_cfun->decl;
3053       fndecl_was_null = true;
3054     }
3055   debug_gimple_stmt (stmt);
3056   if (fndecl_was_null)
3057     current_function_decl = NULL;
3058 }
3059 
3060 /* Verify that call graph edge corresponds to DECL from the associated
3061    statement.  Return true if the verification should fail.  */
3062 
3063 bool
3064 cgraph_edge::verify_corresponds_to_fndecl (tree decl)
3065 {
3066   cgraph_node *node;
3067 
3068   if (!decl || callee->global.inlined_to)
3069     return false;
3070   if (symtab->state == LTO_STREAMING)
3071     return false;
3072   node = cgraph_node::get (decl);
3073 
3074   /* We do not know if a node from a different partition is an alias or what it
3075      aliases and therefore cannot do the former_clone_of check reliably.  When
3076      body_removed is set, we have lost all information about what was alias or
3077      thunk of and also cannot proceed.  */
3078   if (!node
3079       || node->body_removed
3080       || node->in_other_partition
3081       || callee->icf_merged
3082       || callee->in_other_partition)
3083     return false;
3084 
3085   node = node->ultimate_alias_target ();
3086 
3087   /* Optimizers can redirect unreachable calls or calls triggering undefined
3088      behavior to builtin_unreachable.  */
3089 
3090   if (fndecl_built_in_p (callee->decl, BUILT_IN_UNREACHABLE))
3091     return false;
3092 
3093   if (callee->former_clone_of != node->decl
3094       && (node != callee->ultimate_alias_target ())
3095       && !clone_of_p (node, callee))
3096     return true;
3097   else
3098     return false;
3099 }
3100 
3101 /* Verify cgraph nodes of given cgraph node.  */
3102 DEBUG_FUNCTION void
3103 cgraph_node::verify_node (void)
3104 {
3105   cgraph_edge *e;
3106   function *this_cfun = DECL_STRUCT_FUNCTION (decl);
3107   basic_block this_block;
3108   gimple_stmt_iterator gsi;
3109   bool error_found = false;
3110 
3111   if (seen_error ())
3112     return;
3113 
3114   timevar_push (TV_CGRAPH_VERIFY);
3115   error_found |= verify_base ();
3116   for (e = callees; e; e = e->next_callee)
3117     if (e->aux)
3118       {
3119 	error ("aux field set for edge %s->%s",
3120 	       identifier_to_locale (e->caller->name ()),
3121 	       identifier_to_locale (e->callee->name ()));
3122 	error_found = true;
3123       }
3124   if (!count.verify ())
3125     {
3126       error ("cgraph count invalid");
3127       error_found = true;
3128     }
3129   if (global.inlined_to && same_comdat_group)
3130     {
3131       error ("inline clone in same comdat group list");
3132       error_found = true;
3133     }
3134   if (!definition && !in_other_partition && local.local)
3135     {
3136       error ("local symbols must be defined");
3137       error_found = true;
3138     }
3139   if (global.inlined_to && externally_visible)
3140     {
3141       error ("externally visible inline clone");
3142       error_found = true;
3143     }
3144   if (global.inlined_to && address_taken)
3145     {
3146       error ("inline clone with address taken");
3147       error_found = true;
3148     }
3149   if (global.inlined_to && force_output)
3150     {
3151       error ("inline clone is forced to output");
3152       error_found = true;
3153     }
3154   for (e = indirect_calls; e; e = e->next_callee)
3155     {
3156       if (e->aux)
3157 	{
3158 	  error ("aux field set for indirect edge from %s",
3159 		 identifier_to_locale (e->caller->name ()));
3160 	  error_found = true;
3161 	}
3162       if (!e->indirect_unknown_callee
3163 	  || !e->indirect_info)
3164 	{
3165 	  error ("An indirect edge from %s is not marked as indirect or has "
3166 		 "associated indirect_info, the corresponding statement is: ",
3167 		 identifier_to_locale (e->caller->name ()));
3168 	  cgraph_debug_gimple_stmt (this_cfun, e->call_stmt);
3169 	  error_found = true;
3170 	}
3171     }
3172   bool check_comdat = comdat_local_p ();
3173   for (e = callers; e; e = e->next_caller)
3174     {
3175       if (e->verify_count ())
3176 	error_found = true;
3177       if (check_comdat
3178 	  && !in_same_comdat_group_p (e->caller))
3179 	{
3180 	  error ("comdat-local function called by %s outside its comdat",
3181 		 identifier_to_locale (e->caller->name ()));
3182 	  error_found = true;
3183 	}
3184       if (!e->inline_failed)
3185 	{
3186 	  if (global.inlined_to
3187 	      != (e->caller->global.inlined_to
3188 		  ? e->caller->global.inlined_to : e->caller))
3189 	    {
3190 	      error ("inlined_to pointer is wrong");
3191 	      error_found = true;
3192 	    }
3193 	  if (callers->next_caller)
3194 	    {
3195 	      error ("multiple inline callers");
3196 	      error_found = true;
3197 	    }
3198 	}
3199       else
3200 	if (global.inlined_to)
3201 	  {
3202 	    error ("inlined_to pointer set for noninline callers");
3203 	    error_found = true;
3204 	  }
3205     }
3206   for (e = callees; e; e = e->next_callee)
3207     {
3208       if (e->verify_count ())
3209 	error_found = true;
3210       if (gimple_has_body_p (e->caller->decl)
3211 	  && !e->caller->global.inlined_to
3212 	  && !e->speculative
3213 	  /* Optimized out calls are redirected to __builtin_unreachable.  */
3214 	  && (e->count.nonzero_p ()
3215 	      || ! e->callee->decl
3216 	      || !fndecl_built_in_p (e->callee->decl, BUILT_IN_UNREACHABLE))
3217 	  && count
3218 	      == ENTRY_BLOCK_PTR_FOR_FN (DECL_STRUCT_FUNCTION (decl))->count
3219 	  && (!e->count.ipa_p ()
3220 	      && e->count.differs_from_p (gimple_bb (e->call_stmt)->count)))
3221 	{
3222 	  error ("caller edge count does not match BB count");
3223 	  fprintf (stderr, "edge count: ");
3224 	  e->count.dump (stderr);
3225 	  fprintf (stderr, "\n bb count: ");
3226 	  gimple_bb (e->call_stmt)->count.dump (stderr);
3227 	  fprintf (stderr, "\n");
3228 	  error_found = true;
3229 	}
3230     }
3231   for (e = indirect_calls; e; e = e->next_callee)
3232     {
3233       if (e->verify_count ())
3234 	error_found = true;
3235       if (gimple_has_body_p (e->caller->decl)
3236 	  && !e->caller->global.inlined_to
3237 	  && !e->speculative
3238 	  && e->count.ipa_p ()
3239 	  && count
3240 	      == ENTRY_BLOCK_PTR_FOR_FN (DECL_STRUCT_FUNCTION (decl))->count
3241 	  && (!e->count.ipa_p ()
3242 	      && e->count.differs_from_p (gimple_bb (e->call_stmt)->count)))
3243 	{
3244 	  error ("indirect call count does not match BB count");
3245 	  fprintf (stderr, "edge count: ");
3246 	  e->count.dump (stderr);
3247 	  fprintf (stderr, "\n bb count: ");
3248 	  gimple_bb (e->call_stmt)->count.dump (stderr);
3249 	  fprintf (stderr, "\n");
3250 	  error_found = true;
3251 	}
3252     }
3253   if (!callers && global.inlined_to)
3254     {
3255       error ("inlined_to pointer is set but no predecessors found");
3256       error_found = true;
3257     }
3258   if (global.inlined_to == this)
3259     {
3260       error ("inlined_to pointer refers to itself");
3261       error_found = true;
3262     }
3263 
3264   if (clone_of)
3265     {
3266       cgraph_node *first_clone = clone_of->clones;
3267       if (first_clone != this)
3268 	{
3269 	  if (prev_sibling_clone->clone_of != clone_of)
3270 	    {
3271 	      error ("cgraph_node has wrong clone_of");
3272 	      error_found = true;
3273 	    }
3274 	}
3275     }
3276   if (clones)
3277     {
3278       cgraph_node *n;
3279       for (n = clones; n; n = n->next_sibling_clone)
3280 	if (n->clone_of != this)
3281 	  break;
3282       if (n)
3283 	{
3284 	  error ("cgraph_node has wrong clone list");
3285 	  error_found = true;
3286 	}
3287     }
3288   if ((prev_sibling_clone || next_sibling_clone) && !clone_of)
3289     {
3290        error ("cgraph_node is in clone list but it is not clone");
3291        error_found = true;
3292     }
3293   if (!prev_sibling_clone && clone_of && clone_of->clones != this)
3294     {
3295       error ("cgraph_node has wrong prev_clone pointer");
3296       error_found = true;
3297     }
3298   if (prev_sibling_clone && prev_sibling_clone->next_sibling_clone != this)
3299     {
3300       error ("double linked list of clones corrupted");
3301       error_found = true;
3302     }
3303 
3304   if (analyzed && alias)
3305     {
3306       bool ref_found = false;
3307       int i;
3308       ipa_ref *ref = NULL;
3309 
3310       if (callees)
3311 	{
3312 	  error ("Alias has call edges");
3313           error_found = true;
3314 	}
3315       for (i = 0; iterate_reference (i, ref); i++)
3316 	if (ref->use != IPA_REF_ALIAS)
3317 	  {
3318 	    error ("Alias has non-alias reference");
3319 	    error_found = true;
3320 	  }
3321 	else if (ref_found)
3322 	  {
3323 	    error ("Alias has more than one alias reference");
3324 	    error_found = true;
3325 	  }
3326 	else
3327 	  ref_found = true;
3328       if (!ref_found)
3329 	{
3330 	  error ("Analyzed alias has no reference");
3331 	  error_found = true;
3332 	}
3333     }
3334 
3335   if (analyzed && thunk.thunk_p)
3336     {
3337       if (!callees)
3338 	{
3339 	  error ("No edge out of thunk node");
3340           error_found = true;
3341 	}
3342       else if (callees->next_callee)
3343 	{
3344 	  error ("More than one edge out of thunk node");
3345           error_found = true;
3346 	}
3347       if (gimple_has_body_p (decl) && !global.inlined_to)
3348         {
3349 	  error ("Thunk is not supposed to have body");
3350           error_found = true;
3351         }
3352     }
3353   else if (analyzed && gimple_has_body_p (decl)
3354 	   && !TREE_ASM_WRITTEN (decl)
3355 	   && (!DECL_EXTERNAL (decl) || global.inlined_to)
3356 	   && !flag_wpa)
3357     {
3358       if (this_cfun->cfg)
3359 	{
3360 	  hash_set<gimple *> stmts;
3361 	  int i;
3362 	  ipa_ref *ref = NULL;
3363 
3364 	  /* Reach the trees by walking over the CFG, and note the
3365 	     enclosing basic-blocks in the call edges.  */
3366 	  FOR_EACH_BB_FN (this_block, this_cfun)
3367 	    {
3368 	      for (gsi = gsi_start_phis (this_block);
3369 		   !gsi_end_p (gsi); gsi_next (&gsi))
3370 		stmts.add (gsi_stmt (gsi));
3371 	      for (gsi = gsi_start_bb (this_block);
3372 		   !gsi_end_p (gsi);
3373 		   gsi_next (&gsi))
3374 		{
3375 		  gimple *stmt = gsi_stmt (gsi);
3376 		  stmts.add (stmt);
3377 		  if (is_gimple_call (stmt))
3378 		    {
3379 		      cgraph_edge *e = get_edge (stmt);
3380 		      tree decl = gimple_call_fndecl (stmt);
3381 		      if (e)
3382 			{
3383 			  if (e->aux)
3384 			    {
3385 			      error ("shared call_stmt:");
3386 			      cgraph_debug_gimple_stmt (this_cfun, stmt);
3387 			      error_found = true;
3388 			    }
3389 			  if (!e->indirect_unknown_callee)
3390 			    {
3391 			      if (e->verify_corresponds_to_fndecl (decl))
3392 				{
3393 				  error ("edge points to wrong declaration:");
3394 				  debug_tree (e->callee->decl);
3395 				  fprintf (stderr," Instead of:");
3396 				  debug_tree (decl);
3397 				  error_found = true;
3398 				}
3399 			    }
3400 			  else if (decl)
3401 			    {
3402 			      error ("an indirect edge with unknown callee "
3403 				     "corresponding to a call_stmt with "
3404 				     "a known declaration:");
3405 			      error_found = true;
3406 			      cgraph_debug_gimple_stmt (this_cfun, e->call_stmt);
3407 			    }
3408 			  e->aux = (void *)1;
3409 			}
3410 		      else if (decl)
3411 			{
3412 			  error ("missing callgraph edge for call stmt:");
3413 			  cgraph_debug_gimple_stmt (this_cfun, stmt);
3414 			  error_found = true;
3415 			}
3416 		    }
3417 		}
3418 	      }
3419 	    for (i = 0; iterate_reference (i, ref); i++)
3420 	      if (ref->stmt && !stmts.contains (ref->stmt))
3421 		{
3422 		  error ("reference to dead statement");
3423 		  cgraph_debug_gimple_stmt (this_cfun, ref->stmt);
3424 		  error_found = true;
3425 		}
3426 	}
3427       else
3428 	/* No CFG available?!  */
3429 	gcc_unreachable ();
3430 
3431       for (e = callees; e; e = e->next_callee)
3432 	{
3433 	  if (!e->aux)
3434 	    {
3435 	      error ("edge %s->%s has no corresponding call_stmt",
3436 		     identifier_to_locale (e->caller->name ()),
3437 		     identifier_to_locale (e->callee->name ()));
3438 	      cgraph_debug_gimple_stmt (this_cfun, e->call_stmt);
3439 	      error_found = true;
3440 	    }
3441 	  e->aux = 0;
3442 	}
3443       for (e = indirect_calls; e; e = e->next_callee)
3444 	{
3445 	  if (!e->aux && !e->speculative)
3446 	    {
3447 	      error ("an indirect edge from %s has no corresponding call_stmt",
3448 		     identifier_to_locale (e->caller->name ()));
3449 	      cgraph_debug_gimple_stmt (this_cfun, e->call_stmt);
3450 	      error_found = true;
3451 	    }
3452 	  e->aux = 0;
3453 	}
3454     }
3455 
3456   if (nested != NULL)
3457     {
3458       for (cgraph_node *n = nested; n != NULL; n = n->next_nested)
3459 	{
3460 	  if (n->origin == NULL)
3461 	    {
3462 	      error ("missing origin for a node in a nested list");
3463 	      error_found = true;
3464 	    }
3465 	  else if (n->origin != this)
3466 	    {
3467 	      error ("origin points to a different parent");
3468 	      error_found = true;
3469 	      break;
3470 	    }
3471 	}
3472     }
3473   if (next_nested != NULL && origin == NULL)
3474     {
3475       error ("missing origin for a node in a nested list");
3476       error_found = true;
3477     }
3478 
3479   if (error_found)
3480     {
3481       dump (stderr);
3482       internal_error ("verify_cgraph_node failed");
3483     }
3484   timevar_pop (TV_CGRAPH_VERIFY);
3485 }
3486 
3487 /* Verify whole cgraph structure.  */
3488 DEBUG_FUNCTION void
3489 cgraph_node::verify_cgraph_nodes (void)
3490 {
3491   cgraph_node *node;
3492 
3493   if (seen_error ())
3494     return;
3495 
3496   FOR_EACH_FUNCTION (node)
3497     node->verify ();
3498 }
3499 
3500 /* Walk the alias chain to return the function cgraph_node is alias of.
3501    Walk through thunks, too.
3502    When AVAILABILITY is non-NULL, get minimal availability in the chain.
3503    When REF is non-NULL, assume that reference happens in symbol REF
3504    when determining the availability.  */
3505 
3506 cgraph_node *
3507 cgraph_node::function_symbol (enum availability *availability,
3508 			      struct symtab_node *ref)
3509 {
3510   cgraph_node *node = ultimate_alias_target (availability, ref);
3511 
3512   while (node->thunk.thunk_p)
3513     {
3514       ref = node;
3515       node = node->callees->callee;
3516       if (availability)
3517 	{
3518 	  enum availability a;
3519 	  a = node->get_availability (ref);
3520 	  if (a < *availability)
3521 	    *availability = a;
3522 	}
3523       node = node->ultimate_alias_target (availability, ref);
3524     }
3525   return node;
3526 }
3527 
3528 /* Walk the alias chain to return the function cgraph_node is alias of.
3529    Walk through non virtual thunks, too.  Thus we return either a function
3530    or a virtual thunk node.
3531    When AVAILABILITY is non-NULL, get minimal availability in the chain.
3532    When REF is non-NULL, assume that reference happens in symbol REF
3533    when determining the availability.  */
3534 
3535 cgraph_node *
3536 cgraph_node::function_or_virtual_thunk_symbol
3537 				(enum availability *availability,
3538 				 struct symtab_node *ref)
3539 {
3540   cgraph_node *node = ultimate_alias_target (availability, ref);
3541 
3542   while (node->thunk.thunk_p && !node->thunk.virtual_offset_p)
3543     {
3544       ref = node;
3545       node = node->callees->callee;
3546       if (availability)
3547 	{
3548 	  enum availability a;
3549 	  a = node->get_availability (ref);
3550 	  if (a < *availability)
3551 	    *availability = a;
3552 	}
3553       node = node->ultimate_alias_target (availability, ref);
3554     }
3555   return node;
3556 }
3557 
3558 /* When doing LTO, read cgraph_node's body from disk if it is not already
3559    present.  */
3560 
3561 bool
3562 cgraph_node::get_untransformed_body (void)
3563 {
3564   lto_file_decl_data *file_data;
3565   const char *data, *name;
3566   size_t len;
3567   tree decl = this->decl;
3568 
3569   /* Check if body is already there.  Either we have gimple body or
3570      the function is thunk and in that case we set DECL_ARGUMENTS.  */
3571   if (DECL_ARGUMENTS (decl) || gimple_has_body_p (decl))
3572     return false;
3573 
3574   gcc_assert (in_lto_p && !DECL_RESULT (decl));
3575 
3576   timevar_push (TV_IPA_LTO_GIMPLE_IN);
3577 
3578   file_data = lto_file_data;
3579   name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
3580 
3581   /* We may have renamed the declaration, e.g., a static function.  */
3582   name = lto_get_decl_name_mapping (file_data, name);
3583   struct lto_in_decl_state *decl_state
3584 	 = lto_get_function_in_decl_state (file_data, decl);
3585 
3586   data = lto_get_section_data (file_data, LTO_section_function_body,
3587 			       name, &len, decl_state->compressed);
3588   if (!data)
3589     fatal_error (input_location, "%s: section %s is missing",
3590 		 file_data->file_name,
3591 		 name);
3592 
3593   gcc_assert (DECL_STRUCT_FUNCTION (decl) == NULL);
3594 
3595   if (!quiet_flag)
3596     fprintf (stderr, " in:%s", IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
3597   lto_input_function_body (file_data, this, data);
3598   lto_stats.num_function_bodies++;
3599   lto_free_section_data (file_data, LTO_section_function_body, name,
3600 			 data, len, decl_state->compressed);
3601   lto_free_function_in_decl_state_for_node (this);
3602   /* Keep lto file data so ipa-inline-analysis knows about cross module
3603      inlining.  */
3604 
3605   timevar_pop (TV_IPA_LTO_GIMPLE_IN);
3606 
3607   return true;
3608 }
3609 
3610 /* Prepare function body.  When doing LTO, read cgraph_node's body from disk
3611    if it is not already present.  When some IPA transformations are scheduled,
3612    apply them.  */
3613 
3614 bool
3615 cgraph_node::get_body (void)
3616 {
3617   bool updated;
3618 
3619   updated = get_untransformed_body ();
3620 
3621   /* Getting transformed body makes no sense for inline clones;
3622      we should never use this on real clones because they are materialized
3623      early.
3624      TODO: Materializing clones here will likely lead to smaller LTRANS
3625      footprint. */
3626   gcc_assert (!global.inlined_to && !clone_of);
3627   if (ipa_transforms_to_apply.exists ())
3628     {
3629       opt_pass *saved_current_pass = current_pass;
3630       FILE *saved_dump_file = dump_file;
3631       const char *saved_dump_file_name = dump_file_name;
3632       dump_flags_t saved_dump_flags = dump_flags;
3633       dump_file_name = NULL;
3634       set_dump_file (NULL);
3635 
3636       push_cfun (DECL_STRUCT_FUNCTION (decl));
3637       execute_all_ipa_transforms (true);
3638       cgraph_edge::rebuild_edges ();
3639       free_dominance_info (CDI_DOMINATORS);
3640       free_dominance_info (CDI_POST_DOMINATORS);
3641       pop_cfun ();
3642       updated = true;
3643 
3644       current_pass = saved_current_pass;
3645       set_dump_file (saved_dump_file);
3646       dump_file_name = saved_dump_file_name;
3647       dump_flags = saved_dump_flags;
3648     }
3649   return updated;
3650 }
3651 
3652 /* Return the DECL_STRUCT_FUNCTION of the function.  */
3653 
3654 struct function *
3655 cgraph_node::get_fun (void)
3656 {
3657   cgraph_node *node = this;
3658   struct function *fun = DECL_STRUCT_FUNCTION (node->decl);
3659 
3660   while (!fun && node->clone_of)
3661     {
3662       node = node->clone_of;
3663       fun = DECL_STRUCT_FUNCTION (node->decl);
3664     }
3665 
3666   return fun;
3667 }
3668 
3669 /* Verify if the type of the argument matches that of the function
3670    declaration.  If we cannot verify this or there is a mismatch,
3671    return false.  */
3672 
3673 static bool
3674 gimple_check_call_args (gimple *stmt, tree fndecl, bool args_count_match)
3675 {
3676   tree parms, p;
3677   unsigned int i, nargs;
3678 
3679   /* Calls to internal functions always match their signature.  */
3680   if (gimple_call_internal_p (stmt))
3681     return true;
3682 
3683   nargs = gimple_call_num_args (stmt);
3684 
3685   /* Get argument types for verification.  */
3686   if (fndecl)
3687     parms = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
3688   else
3689     parms = TYPE_ARG_TYPES (gimple_call_fntype (stmt));
3690 
3691   /* Verify if the type of the argument matches that of the function
3692      declaration.  If we cannot verify this or there is a mismatch,
3693      return false.  */
3694   if (fndecl && DECL_ARGUMENTS (fndecl))
3695     {
3696       for (i = 0, p = DECL_ARGUMENTS (fndecl);
3697 	   i < nargs;
3698 	   i++, p = DECL_CHAIN (p))
3699 	{
3700 	  tree arg;
3701 	  /* We cannot distinguish a varargs function from the case
3702 	     of excess parameters, still deferring the inlining decision
3703 	     to the callee is possible.  */
3704 	  if (!p)
3705 	    break;
3706 	  arg = gimple_call_arg (stmt, i);
3707 	  if (p == error_mark_node
3708 	      || DECL_ARG_TYPE (p) == error_mark_node
3709 	      || arg == error_mark_node
3710 	      || (!types_compatible_p (DECL_ARG_TYPE (p), TREE_TYPE (arg))
3711 		  && !fold_convertible_p (DECL_ARG_TYPE (p), arg)))
3712             return false;
3713 	}
3714       if (args_count_match && p)
3715 	return false;
3716     }
3717   else if (parms)
3718     {
3719       for (i = 0, p = parms; i < nargs; i++, p = TREE_CHAIN (p))
3720 	{
3721 	  tree arg;
3722 	  /* If this is a varargs function defer inlining decision
3723 	     to callee.  */
3724 	  if (!p)
3725 	    break;
3726 	  arg = gimple_call_arg (stmt, i);
3727 	  if (TREE_VALUE (p) == error_mark_node
3728 	      || arg == error_mark_node
3729 	      || TREE_CODE (TREE_VALUE (p)) == VOID_TYPE
3730 	      || (!types_compatible_p (TREE_VALUE (p), TREE_TYPE (arg))
3731 		  && !fold_convertible_p (TREE_VALUE (p), arg)))
3732             return false;
3733 	}
3734     }
3735   else
3736     {
3737       if (nargs != 0)
3738         return false;
3739     }
3740   return true;
3741 }
3742 
3743 /* Verify if the type of the argument and lhs of CALL_STMT matches
3744    that of the function declaration CALLEE. If ARGS_COUNT_MATCH is
3745    true, the arg count needs to be the same.
3746    If we cannot verify this or there is a mismatch, return false.  */
3747 
3748 bool
3749 gimple_check_call_matching_types (gimple *call_stmt, tree callee,
3750 				  bool args_count_match)
3751 {
3752   tree lhs;
3753 
3754   if ((DECL_RESULT (callee)
3755        && !DECL_BY_REFERENCE (DECL_RESULT (callee))
3756        && (lhs = gimple_call_lhs (call_stmt)) != NULL_TREE
3757        && !useless_type_conversion_p (TREE_TYPE (DECL_RESULT (callee)),
3758                                       TREE_TYPE (lhs))
3759        && !fold_convertible_p (TREE_TYPE (DECL_RESULT (callee)), lhs))
3760       || !gimple_check_call_args (call_stmt, callee, args_count_match))
3761     return false;
3762   return true;
3763 }
3764 
3765 /* Reset all state within cgraph.c so that we can rerun the compiler
3766    within the same process.  For use by toplev::finalize.  */
3767 
3768 void
3769 cgraph_c_finalize (void)
3770 {
3771   symtab = NULL;
3772 
3773   x_cgraph_nodes_queue = NULL;
3774 
3775   cgraph_fnver_htab = NULL;
3776   version_info_node = NULL;
3777 }
3778 
3779 /* A wroker for call_for_symbol_and_aliases.  */
3780 
3781 bool
3782 cgraph_node::call_for_symbol_and_aliases_1 (bool (*callback) (cgraph_node *,
3783 							      void *),
3784 					    void *data,
3785 					    bool include_overwritable)
3786 {
3787   ipa_ref *ref;
3788   FOR_EACH_ALIAS (this, ref)
3789     {
3790       cgraph_node *alias = dyn_cast <cgraph_node *> (ref->referring);
3791       if (include_overwritable
3792 	  || alias->get_availability () > AVAIL_INTERPOSABLE)
3793 	if (alias->call_for_symbol_and_aliases (callback, data,
3794 						include_overwritable))
3795 	  return true;
3796     }
3797   return false;
3798 }
3799 
3800 /* Return true if NODE has thunk.  */
3801 
3802 bool
3803 cgraph_node::has_thunk_p (cgraph_node *node, void *)
3804 {
3805   for (cgraph_edge *e = node->callers; e; e = e->next_caller)
3806     if (e->caller->thunk.thunk_p)
3807       return true;
3808   return false;
3809 }
3810 
3811 /* Expected frequency of executions within the function.  */
3812 
3813 sreal
3814 cgraph_edge::sreal_frequency ()
3815 {
3816   return count.to_sreal_scale (caller->global.inlined_to
3817 			       ? caller->global.inlined_to->count
3818 			       : caller->count);
3819 }
3820 
3821 
3822 /* During LTO stream in this can be used to check whether call can possibly
3823    be internal to the current translation unit.  */
3824 
3825 bool
3826 cgraph_edge::possibly_call_in_translation_unit_p (void)
3827 {
3828   gcc_checking_assert (in_lto_p && caller->prevailing_p ());
3829 
3830   /* While incremental linking we may end up getting function body later.  */
3831   if (flag_incremental_link == INCREMENTAL_LINK_LTO)
3832     return true;
3833 
3834   /* We may be smarter here and avoid stremaing in indirect calls we can't
3835      track, but that would require arranging stremaing the indirect call
3836      summary first.  */
3837   if (!callee)
3838     return true;
3839 
3840   /* If calle is local to the original translation unit, it will be defined.  */
3841   if (!TREE_PUBLIC (callee->decl) && !DECL_EXTERNAL (callee->decl))
3842     return true;
3843 
3844   /* Otherwise we need to lookup prevailing symbol (symbol table is not merged,
3845      yet) and see if it is a definition.  In fact we may also resolve aliases,
3846      but that is probably not too important.  */
3847   symtab_node *node = callee;
3848   for (int n = 10; node->previous_sharing_asm_name && n ; n--)
3849     node = node->previous_sharing_asm_name;
3850   if (node->previous_sharing_asm_name)
3851     node = symtab_node::get_for_asmname (DECL_ASSEMBLER_NAME (callee->decl));
3852   gcc_assert (TREE_PUBLIC (node->decl));
3853   return node->get_availability () >= AVAIL_AVAILABLE;
3854 }
3855 
3856 /* A stashed copy of "symtab" for use by selftest::symbol_table_test.
3857    This needs to be a global so that it can be a GC root, and thus
3858    prevent the stashed copy from being garbage-collected if the GC runs
3859    during a symbol_table_test.  */
3860 
3861 symbol_table *saved_symtab;
3862 
3863 #if CHECKING_P
3864 
3865 namespace selftest {
3866 
3867 /* class selftest::symbol_table_test.  */
3868 
3869 /* Constructor.  Store the old value of symtab, and create a new one.  */
3870 
3871 symbol_table_test::symbol_table_test ()
3872 {
3873   gcc_assert (saved_symtab == NULL);
3874   saved_symtab = symtab;
3875   symtab = new (ggc_cleared_alloc <symbol_table> ()) symbol_table ();
3876 }
3877 
3878 /* Destructor.  Restore the old value of symtab.  */
3879 
3880 symbol_table_test::~symbol_table_test ()
3881 {
3882   gcc_assert (saved_symtab != NULL);
3883   symtab = saved_symtab;
3884   saved_symtab = NULL;
3885 }
3886 
3887 /* Verify that symbol_table_test works.  */
3888 
3889 static void
3890 test_symbol_table_test ()
3891 {
3892   /* Simulate running two selftests involving symbol tables.  */
3893   for (int i = 0; i < 2; i++)
3894     {
3895       symbol_table_test stt;
3896       tree test_decl = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL,
3897 				   get_identifier ("test_decl"),
3898 				   build_function_type_list (void_type_node,
3899 							     NULL_TREE));
3900       cgraph_node *node = cgraph_node::get_create (test_decl);
3901       gcc_assert (node);
3902 
3903       /* Verify that the node has order 0 on both iterations,
3904 	 and thus that nodes have predictable dump names in selftests.  */
3905       ASSERT_EQ (node->order, 0);
3906       ASSERT_STREQ (node->dump_name (), "test_decl/0");
3907     }
3908 }
3909 
3910 /* Run all of the selftests within this file.  */
3911 
3912 void
3913 cgraph_c_tests ()
3914 {
3915   test_symbol_table_test ();
3916 }
3917 
3918 } // namespace selftest
3919 
3920 #endif /* CHECKING_P */
3921 
3922 #include "gt-cgraph.h"
3923