2 Copyright (C) 2012-2020 Free Software Foundation, Inc.
3 Contributed by Jan Hubicka
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
23 #include "coretypes.h"
31 #include "lto-streamer.h"
32 #include "print-tree.h"
34 #include "langhooks.h"
36 #include "ipa-utils.h"
38 #include "stringpool.h"
42 static const char *ipa_ref_use_name
[] = {"read","write","addr","alias"};
44 const char * const ld_plugin_symbol_resolution_names
[]=
49 "prevailing_def_ironly",
55 "prevailing_def_ironly_exp"
58 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at ALIAS
59 until we find an identifier that is not itself a transparent alias. */
62 ultimate_transparent_alias_target (tree alias
)
66 while (IDENTIFIER_TRANSPARENT_ALIAS (target
))
68 gcc_checking_assert (TREE_CHAIN (target
));
69 target
= TREE_CHAIN (target
);
71 gcc_checking_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target
)
72 && ! TREE_CHAIN (target
));
78 /* Hash asmnames ignoring the user specified marks. */
81 symbol_table::decl_assembler_name_hash (const_tree asmname
)
83 if (IDENTIFIER_POINTER (asmname
)[0] == '*')
85 const char *decl_str
= IDENTIFIER_POINTER (asmname
) + 1;
86 size_t ulp_len
= strlen (user_label_prefix
);
90 else if (strncmp (decl_str
, user_label_prefix
, ulp_len
) == 0)
93 return htab_hash_string (decl_str
);
96 return htab_hash_string (IDENTIFIER_POINTER (asmname
));
99 /* Return true if assembler names NAME1 and NAME2 leads to the same symbol
103 symbol_table::assembler_names_equal_p (const char *name1
, const char *name2
)
109 size_t ulp_len
= strlen (user_label_prefix
);
115 else if (strncmp (name1
, user_label_prefix
, ulp_len
) == 0)
122 size_t ulp_len
= strlen (user_label_prefix
);
128 else if (strncmp (name2
, user_label_prefix
, ulp_len
) == 0)
133 return !strcmp (name1
, name2
);
138 /* Compare ASMNAME with the DECL_ASSEMBLER_NAME of DECL. */
141 symbol_table::decl_assembler_name_equal (tree decl
, const_tree asmname
)
143 tree decl_asmname
= DECL_ASSEMBLER_NAME (decl
);
144 const char *decl_str
;
145 const char *asmname_str
;
147 if (decl_asmname
== asmname
)
150 decl_str
= IDENTIFIER_POINTER (decl_asmname
);
151 asmname_str
= IDENTIFIER_POINTER (asmname
);
152 return assembler_names_equal_p (decl_str
, asmname_str
);
156 /* Returns nonzero if P1 and P2 are equal. */
158 /* Insert NODE to assembler name hash. */
161 symbol_table::insert_to_assembler_name_hash (symtab_node
*node
,
164 if (is_a
<varpool_node
*> (node
) && DECL_HARD_REGISTER (node
->decl
))
166 gcc_checking_assert (!node
->previous_sharing_asm_name
167 && !node
->next_sharing_asm_name
);
168 if (assembler_name_hash
)
172 tree decl
= node
->decl
;
174 tree name
= DECL_ASSEMBLER_NAME (node
->decl
);
176 /* C++ FE can produce decls without associated assembler name and insert
177 them to symtab to hold section or TLS information. */
181 hashval_t hash
= decl_assembler_name_hash (name
);
182 aslot
= assembler_name_hash
->find_slot_with_hash (name
, hash
, INSERT
);
183 gcc_assert (*aslot
!= node
);
184 node
->next_sharing_asm_name
= (symtab_node
*)*aslot
;
186 (*aslot
)->previous_sharing_asm_name
= node
;
189 /* Update also possible inline clones sharing a decl. */
190 cnode
= dyn_cast
<cgraph_node
*> (node
);
191 if (cnode
&& cnode
->clones
&& with_clones
)
192 for (cnode
= cnode
->clones
; cnode
; cnode
= cnode
->next_sibling_clone
)
193 if (cnode
->decl
== decl
)
194 insert_to_assembler_name_hash (cnode
, true);
199 /* Remove NODE from assembler name hash. */
202 symbol_table::unlink_from_assembler_name_hash (symtab_node
*node
,
205 if (assembler_name_hash
)
208 tree decl
= node
->decl
;
210 if (node
->next_sharing_asm_name
)
211 node
->next_sharing_asm_name
->previous_sharing_asm_name
212 = node
->previous_sharing_asm_name
;
213 if (node
->previous_sharing_asm_name
)
215 node
->previous_sharing_asm_name
->next_sharing_asm_name
216 = node
->next_sharing_asm_name
;
220 tree name
= DECL_ASSEMBLER_NAME (node
->decl
);
226 hashval_t hash
= decl_assembler_name_hash (name
);
227 slot
= assembler_name_hash
->find_slot_with_hash (name
, hash
,
229 gcc_assert (*slot
== node
);
230 if (!node
->next_sharing_asm_name
)
231 assembler_name_hash
->clear_slot (slot
);
233 *slot
= node
->next_sharing_asm_name
;
235 node
->next_sharing_asm_name
= NULL
;
236 node
->previous_sharing_asm_name
= NULL
;
238 /* Update also possible inline clones sharing a decl. */
239 cnode
= dyn_cast
<cgraph_node
*> (node
);
240 if (cnode
&& cnode
->clones
&& with_clones
)
241 for (cnode
= cnode
->clones
; cnode
; cnode
= cnode
->next_sibling_clone
)
242 if (cnode
->decl
== decl
)
243 unlink_from_assembler_name_hash (cnode
, true);
247 /* Arrange node to be first in its entry of assembler_name_hash. */
250 symbol_table::symtab_prevail_in_asm_name_hash (symtab_node
*node
)
252 unlink_from_assembler_name_hash (node
, false);
253 insert_to_assembler_name_hash (node
, false);
256 /* Initialize asm name hash unless. */
259 symbol_table::symtab_initialize_asm_name_hash (void)
262 if (!assembler_name_hash
)
264 assembler_name_hash
= hash_table
<asmname_hasher
>::create_ggc (10);
265 FOR_EACH_SYMBOL (node
)
266 insert_to_assembler_name_hash (node
, false);
270 /* Set the DECL_ASSEMBLER_NAME and update symtab hashtables. */
273 symbol_table::change_decl_assembler_name (tree decl
, tree name
)
275 symtab_node
*node
= NULL
;
277 /* We can have user ASM names on things, like global register variables, that
278 are not in the symbol table. */
279 if ((VAR_P (decl
) && (TREE_STATIC (decl
) || DECL_EXTERNAL (decl
)))
280 || TREE_CODE (decl
) == FUNCTION_DECL
)
281 node
= symtab_node::get (decl
);
282 if (!DECL_ASSEMBLER_NAME_SET_P (decl
))
284 SET_DECL_ASSEMBLER_NAME (decl
, name
);
286 insert_to_assembler_name_hash (node
, true);
290 if (name
== DECL_ASSEMBLER_NAME (decl
))
293 tree alias
= (IDENTIFIER_TRANSPARENT_ALIAS (DECL_ASSEMBLER_NAME (decl
))
294 ? TREE_CHAIN (DECL_ASSEMBLER_NAME (decl
))
297 unlink_from_assembler_name_hash (node
, true);
299 const char *old_name
= IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl
));
300 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl
))
301 && DECL_RTL_SET_P (decl
))
302 warning (0, "%qD renamed after being referenced in assembly", decl
);
304 SET_DECL_ASSEMBLER_NAME (decl
, name
);
307 IDENTIFIER_TRANSPARENT_ALIAS (name
) = 1;
308 TREE_CHAIN (name
) = alias
;
310 /* If we change assembler name, also all transparent aliases must
311 be updated. There are three kinds - those having same assembler name,
312 those being renamed in varasm.c and weakref being renamed by the
316 insert_to_assembler_name_hash (node
, true);
318 for (unsigned i
= 0; node
->iterate_direct_aliases (i
, ref
); i
++)
320 struct symtab_node
*alias
= ref
->referring
;
321 if (alias
->transparent_alias
&& !alias
->weakref
322 && symbol_table::assembler_names_equal_p
323 (old_name
, IDENTIFIER_POINTER (
324 DECL_ASSEMBLER_NAME (alias
->decl
))))
325 change_decl_assembler_name (alias
->decl
, name
);
326 else if (alias
->transparent_alias
327 && IDENTIFIER_TRANSPARENT_ALIAS (alias
->decl
))
329 gcc_assert (TREE_CHAIN (DECL_ASSEMBLER_NAME (alias
->decl
))
330 && IDENTIFIER_TRANSPARENT_ALIAS
331 (DECL_ASSEMBLER_NAME (alias
->decl
)));
333 TREE_CHAIN (DECL_ASSEMBLER_NAME (alias
->decl
)) =
334 ultimate_transparent_alias_target
335 (DECL_ASSEMBLER_NAME (node
->decl
));
337 #ifdef ASM_OUTPUT_WEAKREF
338 else gcc_assert (!alias
->transparent_alias
|| alias
->weakref
);
340 else gcc_assert (!alias
->transparent_alias
);
343 gcc_assert (!node
->transparent_alias
|| !node
->definition
345 || TREE_CHAIN (DECL_ASSEMBLER_NAME (decl
))
346 || symbol_table::assembler_names_equal_p
347 (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl
)),
350 (node
->get_alias_target ()->decl
))));
355 /* Hash sections by their names. */
358 section_name_hasher::hash (section_hash_entry
*n
)
360 return htab_hash_string (n
->name
);
363 /* Return true if section P1 name equals to P2. */
366 section_name_hasher::equal (section_hash_entry
*n1
, const char *name
)
368 return n1
->name
== name
|| !strcmp (n1
->name
, name
);
371 /* Add node into symbol table. This function is not used directly, but via
372 cgraph/varpool node creation routines. */
375 symtab_node::register_symbol (void)
377 symtab
->register_symbol (this);
379 if (!decl
->decl_with_vis
.symtab_node
)
380 decl
->decl_with_vis
.symtab_node
= this;
384 /* Be sure to do this last; C++ FE might create new nodes via
385 DECL_ASSEMBLER_NAME langhook! */
386 symtab
->insert_to_assembler_name_hash (this, false);
389 /* Remove NODE from same comdat group. */
392 symtab_node::remove_from_same_comdat_group (void)
394 if (same_comdat_group
)
397 for (prev
= same_comdat_group
;
398 prev
->same_comdat_group
!= this;
399 prev
= prev
->same_comdat_group
)
401 if (same_comdat_group
== prev
)
402 prev
->same_comdat_group
= NULL
;
404 prev
->same_comdat_group
= same_comdat_group
;
405 same_comdat_group
= NULL
;
406 set_comdat_group (NULL
);
410 /* Remove node from symbol table. This function is not used directly, but via
411 cgraph/varpool node removal routines. */
414 symtab_node::unregister (void)
416 remove_all_references ();
417 remove_all_referring ();
419 /* Remove reference to section. */
420 set_section_for_node (NULL
);
422 remove_from_same_comdat_group ();
424 symtab
->unregister (this);
426 /* During LTO symtab merging we temporarily corrupt decl to symtab node
428 gcc_assert (decl
->decl_with_vis
.symtab_node
|| in_lto_p
);
429 if (decl
->decl_with_vis
.symtab_node
== this)
431 symtab_node
*replacement_node
= NULL
;
432 if (cgraph_node
*cnode
= dyn_cast
<cgraph_node
*> (this))
433 replacement_node
= cnode
->find_replacement ();
434 decl
->decl_with_vis
.symtab_node
= replacement_node
;
436 if (!is_a
<varpool_node
*> (this) || !DECL_HARD_REGISTER (decl
))
437 symtab
->unlink_from_assembler_name_hash (this, false);
438 if (in_init_priority_hash
)
439 symtab
->init_priority_hash
->remove (this);
443 /* Remove symbol from symbol table. */
446 symtab_node::remove (void)
448 if (cgraph_node
*cnode
= dyn_cast
<cgraph_node
*> (this))
450 else if (varpool_node
*vnode
= dyn_cast
<varpool_node
*> (this))
454 /* Add NEW_ to the same comdat group that OLD is in. */
457 symtab_node::add_to_same_comdat_group (symtab_node
*old_node
)
459 gcc_assert (old_node
->get_comdat_group ());
460 gcc_assert (!same_comdat_group
);
461 gcc_assert (this != old_node
);
463 set_comdat_group (old_node
->get_comdat_group ());
464 same_comdat_group
= old_node
;
465 if (!old_node
->same_comdat_group
)
466 old_node
->same_comdat_group
= this;
470 for (n
= old_node
->same_comdat_group
;
471 n
->same_comdat_group
!= old_node
;
472 n
= n
->same_comdat_group
)
474 n
->same_comdat_group
= this;
478 if (comdat_local_p ()
479 && (n
= dyn_cast
<cgraph_node
*> (this)) != NULL
)
481 for (cgraph_edge
*e
= n
->callers
; e
; e
= e
->next_caller
)
482 if (e
->caller
->inlined_to
)
483 e
->caller
->inlined_to
->calls_comdat_local
= true;
485 e
->caller
->calls_comdat_local
= true;
489 /* Dissolve the same_comdat_group list in which NODE resides. */
492 symtab_node::dissolve_same_comdat_group_list (void)
494 symtab_node
*n
= this;
497 if (!same_comdat_group
)
501 next
= n
->same_comdat_group
;
502 n
->same_comdat_group
= NULL
;
503 if (dyn_cast
<cgraph_node
*> (n
))
504 dyn_cast
<cgraph_node
*> (n
)->calls_comdat_local
= false;
505 /* Clear comdat_group for comdat locals, since
506 make_decl_local doesn't. */
507 if (!TREE_PUBLIC (n
->decl
))
508 n
->set_comdat_group (NULL
);
514 /* Return printable assembler name of NODE.
515 This function is used only for debugging. When assembler name
516 is unknown go with identifier name. */
519 symtab_node::asm_name () const
521 if (!DECL_ASSEMBLER_NAME_SET_P (decl
))
523 return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl
));
526 /* Return printable identifier name. */
529 symtab_node::name () const
531 if (!DECL_NAME (decl
))
533 if (DECL_ASSEMBLER_NAME_SET_P (decl
))
538 return lang_hooks
.decl_printable_name (decl
, 2);
542 symtab_node::get_dump_name (bool asm_name_p
) const
545 const char *fname
= asm_name_p
? asm_name () : name ();
546 unsigned l
= strlen (fname
);
548 char *s
= (char *)ggc_internal_cleared_alloc (l
+ EXTRA
);
549 snprintf (s
, l
+ EXTRA
, "%s/%d", fname
, order
);
555 symtab_node::dump_name () const
557 return get_dump_name (false);
561 symtab_node::dump_asm_name () const
563 return get_dump_name (true);
566 /* Return ipa reference from this symtab_node to
567 REFERRED_NODE or REFERRED_VARPOOL_NODE. USE_TYPE specify type
571 symtab_node::create_reference (symtab_node
*referred_node
,
572 enum ipa_ref_use use_type
)
574 return create_reference (referred_node
, use_type
, NULL
);
578 /* Return ipa reference from this symtab_node to
579 REFERRED_NODE or REFERRED_VARPOOL_NODE. USE_TYPE specify type
580 of the use and STMT the statement (if it exists). */
583 symtab_node::create_reference (symtab_node
*referred_node
,
584 enum ipa_ref_use use_type
, gimple
*stmt
)
586 ipa_ref
*ref
= NULL
, *ref2
= NULL
;
587 ipa_ref_list
*list
, *list2
;
588 ipa_ref_t
*old_references
;
590 gcc_checking_assert (!stmt
|| is_a
<cgraph_node
*> (this));
591 gcc_checking_assert (use_type
!= IPA_REF_ALIAS
|| !stmt
);
594 old_references
= vec_safe_address (list
->references
);
595 vec_safe_grow (list
->references
, vec_safe_length (list
->references
) + 1,
597 ref
= &list
->references
->last ();
599 list2
= &referred_node
->ref_list
;
601 /* IPA_REF_ALIAS is always inserted at the beginning of the list. */
602 if(use_type
== IPA_REF_ALIAS
)
604 list2
->referring
.safe_insert (0, ref
);
605 ref
->referred_index
= 0;
607 for (unsigned int i
= 1; i
< list2
->referring
.length (); i
++)
608 list2
->referring
[i
]->referred_index
= i
;
612 list2
->referring
.safe_push (ref
);
613 ref
->referred_index
= list2
->referring
.length () - 1;
616 ref
->referring
= this;
617 ref
->referred
= referred_node
;
619 ref
->lto_stmt_uid
= 0;
620 ref
->speculative_id
= 0;
622 ref
->speculative
= 0;
624 /* If vector was moved in memory, update pointers. */
625 if (old_references
!= list
->references
->address ())
628 for (i
= 0; iterate_reference(i
, ref2
); i
++)
629 ref2
->referred_ref_list ()->referring
[ref2
->referred_index
] = ref2
;
635 symtab_node::maybe_create_reference (tree val
, gimple
*stmt
)
638 ipa_ref_use use_type
;
640 switch (TREE_CODE (val
))
643 use_type
= IPA_REF_LOAD
;
646 use_type
= IPA_REF_ADDR
;
649 gcc_assert (!handled_component_p (val
));
653 val
= get_base_var (val
);
654 if (val
&& VAR_OR_FUNCTION_DECL_P (val
))
656 symtab_node
*referred
= symtab_node::get (val
);
657 gcc_checking_assert (referred
);
658 return create_reference (referred
, use_type
, stmt
);
663 /* Clone all references from symtab NODE to this symtab_node. */
666 symtab_node::clone_references (symtab_node
*node
)
668 ipa_ref
*ref
= NULL
, *ref2
= NULL
;
670 for (i
= 0; node
->iterate_reference (i
, ref
); i
++)
672 bool speculative
= ref
->speculative
;
673 unsigned int stmt_uid
= ref
->lto_stmt_uid
;
674 unsigned int spec_id
= ref
->speculative_id
;
676 ref2
= create_reference (ref
->referred
, ref
->use
, ref
->stmt
);
677 ref2
->speculative
= speculative
;
678 ref2
->lto_stmt_uid
= stmt_uid
;
679 ref2
->speculative_id
= spec_id
;
683 /* Clone all referring from symtab NODE to this symtab_node. */
686 symtab_node::clone_referring (symtab_node
*node
)
688 ipa_ref
*ref
= NULL
, *ref2
= NULL
;
690 for (i
= 0; node
->iterate_referring(i
, ref
); i
++)
692 bool speculative
= ref
->speculative
;
693 unsigned int stmt_uid
= ref
->lto_stmt_uid
;
694 unsigned int spec_id
= ref
->speculative_id
;
696 ref2
= ref
->referring
->create_reference (this, ref
->use
, ref
->stmt
);
697 ref2
->speculative
= speculative
;
698 ref2
->lto_stmt_uid
= stmt_uid
;
699 ref2
->speculative_id
= spec_id
;
703 /* Clone reference REF to this symtab_node and set its stmt to STMT. */
706 symtab_node::clone_reference (ipa_ref
*ref
, gimple
*stmt
)
708 bool speculative
= ref
->speculative
;
709 unsigned int stmt_uid
= ref
->lto_stmt_uid
;
710 unsigned int spec_id
= ref
->speculative_id
;
713 ref2
= create_reference (ref
->referred
, ref
->use
, stmt
);
714 ref2
->speculative
= speculative
;
715 ref2
->lto_stmt_uid
= stmt_uid
;
716 ref2
->speculative_id
= spec_id
;
720 /* Find the structure describing a reference to REFERRED_NODE
721 and associated with statement STMT. */
724 symtab_node::find_reference (symtab_node
*referred_node
,
725 gimple
*stmt
, unsigned int lto_stmt_uid
)
730 for (i
= 0; iterate_reference (i
, r
); i
++)
731 if (r
->referred
== referred_node
733 && ((stmt
&& r
->stmt
== stmt
)
734 || (lto_stmt_uid
&& r
->lto_stmt_uid
== lto_stmt_uid
)
735 || (!stmt
&& !lto_stmt_uid
&& !r
->stmt
&& !r
->lto_stmt_uid
)))
740 /* Remove all references that are associated with statement STMT. */
743 symtab_node::remove_stmt_references (gimple
*stmt
)
748 while (iterate_reference (i
, r
))
750 r
->remove_reference ();
755 /* Remove all stmt references in non-speculative references.
756 Those are not maintained during inlining & cloning.
757 The exception are speculative references that are updated along
758 with callgraph edges associated with them. */
761 symtab_node::clear_stmts_in_references (void)
766 for (i
= 0; iterate_reference (i
, r
); i
++)
771 r
->speculative_id
= 0;
775 /* Remove all references in ref list. */
778 symtab_node::remove_all_references (void)
780 while (vec_safe_length (ref_list
.references
))
781 ref_list
.references
->last ().remove_reference ();
782 vec_free (ref_list
.references
);
785 /* Remove all referring items in ref list. */
788 symtab_node::remove_all_referring (void)
790 while (ref_list
.referring
.length ())
791 ref_list
.referring
.last ()->remove_reference ();
792 ref_list
.referring
.release ();
795 /* Dump references in ref list to FILE. */
798 symtab_node::dump_references (FILE *file
)
802 for (i
= 0; iterate_reference (i
, ref
); i
++)
804 fprintf (file
, "%s (%s) ", ref
->referred
->dump_asm_name (),
805 ipa_ref_use_name
[ref
->use
]);
806 if (ref
->speculative
)
807 fprintf (file
, "(speculative) ");
809 fprintf (file
, "\n");
812 /* Dump referring in list to FILE. */
815 symtab_node::dump_referring (FILE *file
)
819 for (i
= 0; iterate_referring(i
, ref
); i
++)
821 fprintf (file
, "%s (%s) ", ref
->referring
->dump_asm_name (),
822 ipa_ref_use_name
[ref
->use
]);
823 if (ref
->speculative
)
824 fprintf (file
, "(speculative) ");
826 fprintf (file
, "\n");
829 static const char * const symtab_type_names
[] = {"symbol", "function", "variable"};
831 /* Dump the visibility of the symbol. */
834 symtab_node::get_visibility_string () const
836 static const char * const visibility_types
[]
837 = { "default", "protected", "hidden", "internal" };
838 return visibility_types
[DECL_VISIBILITY (decl
)];
841 /* Dump the type_name of the symbol. */
843 symtab_node::get_symtab_type_string () const
845 return symtab_type_names
[type
];
848 /* Dump base fields of symtab nodes to F. Not to be used directly. */
851 symtab_node::dump_base (FILE *f
)
853 static const char * const visibility_types
[] = {
854 "default", "protected", "hidden", "internal"
857 fprintf (f
, "%s (%s)", dump_asm_name (), name ());
858 dump_addr (f
, " @", (void *)this);
859 fprintf (f
, "\n Type: %s", symtab_type_names
[type
]);
862 fprintf (f
, " definition");
864 fprintf (f
, " analyzed");
866 fprintf (f
, " alias");
867 if (transparent_alias
)
868 fprintf (f
, " transparent_alias");
870 fprintf (f
, " weakref");
872 fprintf (f
, " symver");
873 if (cpp_implicit_alias
)
874 fprintf (f
, " cpp_implicit_alias");
876 fprintf (f
, " target:%s",
877 DECL_P (alias_target
)
878 ? IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME
880 : IDENTIFIER_POINTER (alias_target
));
882 fprintf (f
, "\n Body removed by symtab_remove_unreachable_nodes");
883 fprintf (f
, "\n Visibility:");
884 if (in_other_partition
)
885 fprintf (f
, " in_other_partition");
886 if (used_from_other_partition
)
887 fprintf (f
, " used_from_other_partition");
889 fprintf (f
, " force_output");
891 fprintf (f
, " forced_by_abi");
892 if (externally_visible
)
893 fprintf (f
, " externally_visible");
895 fprintf (f
, " no_reorder");
896 if (resolution
!= LDPR_UNKNOWN
)
898 ld_plugin_symbol_resolution_names
[(int)resolution
]);
899 if (TREE_ASM_WRITTEN (decl
))
900 fprintf (f
, " asm_written");
901 if (DECL_EXTERNAL (decl
))
902 fprintf (f
, " external");
903 if (TREE_PUBLIC (decl
))
904 fprintf (f
, " public");
905 if (DECL_COMMON (decl
))
906 fprintf (f
, " common");
907 if (DECL_WEAK (decl
))
908 fprintf (f
, " weak");
909 if (DECL_DLLIMPORT_P (decl
))
910 fprintf (f
, " dll_import");
911 if (DECL_COMDAT (decl
))
912 fprintf (f
, " comdat");
913 if (get_comdat_group ())
914 fprintf (f
, " comdat_group:%s",
915 IDENTIFIER_POINTER (get_comdat_group_id ()));
916 if (DECL_ONE_ONLY (decl
))
917 fprintf (f
, " one_only");
919 fprintf (f
, " section:%s",
921 if (implicit_section
)
922 fprintf (f
," (implicit_section)");
923 if (DECL_VISIBILITY_SPECIFIED (decl
))
924 fprintf (f
, " visibility_specified");
925 if (DECL_VISIBILITY (decl
))
926 fprintf (f
, " visibility:%s",
927 visibility_types
[DECL_VISIBILITY (decl
)]);
928 if (DECL_VIRTUAL_P (decl
))
929 fprintf (f
, " virtual");
930 if (DECL_ARTIFICIAL (decl
))
931 fprintf (f
, " artificial");
932 if (TREE_CODE (decl
) == FUNCTION_DECL
)
934 if (DECL_STATIC_CONSTRUCTOR (decl
))
935 fprintf (f
, " constructor");
936 if (DECL_STATIC_DESTRUCTOR (decl
))
937 fprintf (f
, " destructor");
940 fprintf (f
, " ifunc_resolver");
943 if (same_comdat_group
)
944 fprintf (f
, " Same comdat group as: %s\n",
945 same_comdat_group
->dump_asm_name ());
946 if (next_sharing_asm_name
)
947 fprintf (f
, " next sharing asm name: %i\n",
948 next_sharing_asm_name
->order
);
949 if (previous_sharing_asm_name
)
950 fprintf (f
, " previous sharing asm name: %i\n",
951 previous_sharing_asm_name
->order
);
954 fprintf (f
, " Address is taken.\n");
957 fprintf (f
, " Aux:");
958 dump_addr (f
, " @", (void *)aux
);
962 fprintf (f
, " References: ");
964 fprintf (f
, " Referring: ");
967 fprintf (f
, " Read from file: %s\n",
968 lto_file_data
->file_name
);
971 /* Dump symtab node to F. */
974 symtab_node::dump (FILE *f
)
976 if (cgraph_node
*cnode
= dyn_cast
<cgraph_node
*> (this))
978 else if (varpool_node
*vnode
= dyn_cast
<varpool_node
*> (this))
983 symtab_node::dump_graphviz (FILE *f
)
985 if (cgraph_node
*cnode
= dyn_cast
<cgraph_node
*> (this))
986 cnode
->dump_graphviz (f
);
990 symbol_table::dump (FILE *f
)
993 fprintf (f
, "Symbol table:\n\n");
994 FOR_EACH_SYMBOL (node
)
999 symbol_table::dump_graphviz (FILE *f
)
1002 fprintf (f
, "digraph symtab {\n");
1003 FOR_EACH_SYMBOL (node
)
1004 node
->dump_graphviz (f
);
1009 symbol_table::debug (void)
1014 /* Return the cgraph node that has ASMNAME for its DECL_ASSEMBLER_NAME.
1015 Return NULL if there's no such node. */
1018 symtab_node::get_for_asmname (const_tree asmname
)
1022 symtab
->symtab_initialize_asm_name_hash ();
1023 hashval_t hash
= symtab
->decl_assembler_name_hash (asmname
);
1025 = symtab
->assembler_name_hash
->find_slot_with_hash (asmname
, hash
,
1036 /* Dump symtab node NODE to stderr. */
1039 symtab_node::debug (void)
1044 /* Verify common part of symtab nodes. */
1047 /* Disable warnings about missing quoting in GCC diagnostics for
1048 the verification errors. Their format strings don't follow GCC
1049 diagnostic conventions and the calls are ultimately followed by
1050 one to internal_error. */
1051 # pragma GCC diagnostic push
1052 # pragma GCC diagnostic ignored "-Wformat-diag"
1056 symtab_node::verify_base (void)
1058 bool error_found
= false;
1059 symtab_node
*hashed_node
;
1061 if (is_a
<cgraph_node
*> (this))
1063 if (TREE_CODE (decl
) != FUNCTION_DECL
)
1065 error ("function symbol is not function");
1068 else if ((lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl
))
1070 != dyn_cast
<cgraph_node
*> (this)->ifunc_resolver
)
1072 error ("inconsistent %<ifunc%> attribute");
1076 else if (is_a
<varpool_node
*> (this))
1080 error ("variable symbol is not variable");
1086 error ("node has unknown type");
1089 if (order
< 0 || order
>= symtab
->order
)
1091 error ("node has invalid order %i", order
);
1095 if (symtab
->state
!= LTO_STREAMING
)
1097 hashed_node
= symtab_node::get (decl
);
1100 error ("node not found node->decl->decl_with_vis.symtab_node");
1103 if (hashed_node
!= this
1104 && (!is_a
<cgraph_node
*> (this)
1105 || !dyn_cast
<cgraph_node
*> (this)->clone_of
1106 || dyn_cast
<cgraph_node
*> (this)->clone_of
->decl
!= decl
))
1108 error ("node differs from node->decl->decl_with_vis.symtab_node");
1112 if (symtab
->assembler_name_hash
)
1114 hashed_node
= symtab_node::get_for_asmname (DECL_ASSEMBLER_NAME (decl
));
1117 if (hashed_node
->previous_sharing_asm_name
)
1119 error ("assembler name hash list corrupted");
1122 else if (previous_sharing_asm_name
== NULL
)
1124 if (hashed_node
!= this)
1126 error ("assembler name hash list corrupted");
1130 else if (!(is_a
<varpool_node
*> (this) && DECL_HARD_REGISTER (decl
)))
1132 if (!asmname_hasher::equal (previous_sharing_asm_name
,
1133 DECL_ASSEMBLER_NAME (decl
)))
1135 error ("node not found in symtab assembler name hash");
1141 if (previous_sharing_asm_name
1142 && previous_sharing_asm_name
->next_sharing_asm_name
!= this)
1144 error ("double linked list of assembler names corrupted");
1147 if (body_removed
&& definition
)
1149 error ("node has body_removed but is definition");
1152 if (analyzed
&& !definition
)
1154 error ("node is analyzed but it is not a definition");
1157 if (cpp_implicit_alias
&& !alias
)
1159 error ("node is alias but not implicit alias");
1162 if (alias
&& !definition
&& !weakref
)
1164 error ("node is alias but not definition");
1167 if (weakref
&& !transparent_alias
)
1169 error ("node is weakref but not an transparent_alias");
1172 if (transparent_alias
&& !alias
)
1174 error ("node is transparent_alias but not an alias");
1177 if (symver
&& !alias
)
1179 error ("node is symver but not alias");
1182 /* Limitation of gas requires us to output targets of symver aliases as
1183 global symbols. This is binutils PR 25295. */
1185 && (!TREE_PUBLIC (get_alias_target ()->decl
)
1186 || DECL_VISIBILITY (get_alias_target ()->decl
) != VISIBILITY_DEFAULT
))
1188 error ("symver target is not exported with default visibility");
1192 && (!TREE_PUBLIC (decl
)
1193 || DECL_VISIBILITY (decl
) != VISIBILITY_DEFAULT
))
1195 error ("symver is not exported with default visibility");
1198 if (same_comdat_group
)
1200 symtab_node
*n
= same_comdat_group
;
1202 if (!n
->get_comdat_group ())
1204 error ("node is in same_comdat_group list but has no comdat_group");
1207 if (n
->get_comdat_group () != get_comdat_group ())
1209 error ("same_comdat_group list across different groups");
1212 if (n
->type
!= type
)
1214 error ("mixing different types of symbol in same comdat groups is not supported");
1219 error ("node is alone in a comdat group");
1224 if (!n
->same_comdat_group
)
1226 error ("same_comdat_group is not a circular list");
1230 n
= n
->same_comdat_group
;
1233 if (comdat_local_p ())
1235 ipa_ref
*ref
= NULL
;
1237 for (int i
= 0; iterate_referring (i
, ref
); ++i
)
1239 if (!in_same_comdat_group_p (ref
->referring
))
1241 error ("comdat-local symbol referred to by %s outside its "
1243 identifier_to_locale (ref
->referring
->name()));
1249 if (implicit_section
&& !get_section ())
1251 error ("implicit_section flag is set but section isn%'t");
1254 if (get_section () && get_comdat_group ()
1255 && !implicit_section
1256 && !lookup_attribute ("section", DECL_ATTRIBUTES (decl
)))
1258 error ("Both section and comdat group is set");
1261 /* TODO: Add string table for sections, so we do not keep holding duplicated
1263 if (alias
&& definition
1264 && get_section () != get_alias_target ()->get_section ()
1266 || !get_alias_target ()->get_section ()
1267 || strcmp (get_section(),
1268 get_alias_target ()->get_section ())))
1270 error ("Alias and target%'s section differs");
1271 get_alias_target ()->dump (stderr
);
1274 if (alias
&& definition
1275 && get_comdat_group () != get_alias_target ()->get_comdat_group ())
1277 error ("Alias and target%'s comdat groups differs");
1278 get_alias_target ()->dump (stderr
);
1281 if (transparent_alias
&& definition
&& !weakref
)
1283 symtab_node
*to
= get_alias_target ();
1285 = IDENTIFIER_POINTER (
1286 ultimate_transparent_alias_target (DECL_ASSEMBLER_NAME (decl
)));
1288 = IDENTIFIER_POINTER (
1289 ultimate_transparent_alias_target (DECL_ASSEMBLER_NAME (to
->decl
)));
1290 if (!symbol_table::assembler_names_equal_p (name1
, name2
))
1292 error ("Transparent alias and target%'s assembler names differs");
1293 get_alias_target ()->dump (stderr
);
1297 if (transparent_alias
&& definition
1298 && get_alias_target()->transparent_alias
&& get_alias_target()->analyzed
)
1300 error ("Chained transparent aliases");
1301 get_alias_target ()->dump (stderr
);
1308 /* Verify consistency of NODE. */
1311 symtab_node::verify (void)
1316 timevar_push (TV_CGRAPH_VERIFY
);
1317 if (cgraph_node
*node
= dyn_cast
<cgraph_node
*> (this))
1318 node
->verify_node ();
1323 internal_error ("symtab_node::verify failed");
1325 timevar_pop (TV_CGRAPH_VERIFY
);
1328 /* Verify symbol table for internal consistency. */
1331 symtab_node::verify_symtab_nodes (void)
1334 hash_map
<tree
, symtab_node
*> comdat_head_map (251);
1337 for (anode
= symtab
->first_asm_symbol (); anode
; anode
= anode
->next
)
1338 if (anode
->order
< 0 || anode
->order
>= symtab
->order
)
1340 error ("invalid order in asm node %i", anode
->order
);
1341 internal_error ("symtab_node::verify failed");
1344 FOR_EACH_SYMBOL (node
)
1347 if (node
->get_comdat_group ())
1349 symtab_node
**entry
, *s
;
1352 entry
= &comdat_head_map
.get_or_insert (node
->get_comdat_group (),
1356 else if (!DECL_EXTERNAL (node
->decl
))
1358 for (s
= (*entry
)->same_comdat_group
;
1359 s
!= NULL
&& s
!= node
&& s
!= *entry
;
1360 s
= s
->same_comdat_group
)
1362 if (!s
|| s
== *entry
)
1364 error ("Two symbols with same comdat_group are not linked by "
1365 "the same_comdat_group list.");
1368 internal_error ("symtab_node::verify failed");
1376 # pragma GCC diagnostic pop
1379 /* Make DECL local. FIXME: We shouldn't need to mess with rtl this early,
1380 but other code such as notice_global_symbol generates rtl. */
1383 symtab_node::make_decl_local (void)
1390 IDENTIFIER_TRANSPARENT_ALIAS (DECL_ASSEMBLER_NAME (decl
)) = 0;
1391 TREE_CHAIN (DECL_ASSEMBLER_NAME (decl
)) = NULL_TREE
;
1392 symtab
->change_decl_assembler_name
1393 (decl
, DECL_ASSEMBLER_NAME (get_alias_target ()->decl
));
1394 DECL_ATTRIBUTES (decl
) = remove_attribute ("weakref",
1395 DECL_ATTRIBUTES (decl
));
1397 /* Avoid clearing comdat_groups on comdat-local decls. */
1398 else if (TREE_PUBLIC (decl
) == 0)
1401 /* Localizing a symbol also make all its transparent aliases local. */
1403 for (unsigned i
= 0; iterate_direct_aliases (i
, ref
); i
++)
1405 struct symtab_node
*alias
= ref
->referring
;
1406 if (alias
->transparent_alias
)
1407 alias
->make_decl_local ();
1412 DECL_COMMON (decl
) = 0;
1413 /* ADDRESSABLE flag is not defined for public symbols. */
1414 TREE_ADDRESSABLE (decl
) = 1;
1415 TREE_STATIC (decl
) = 1;
1418 gcc_assert (TREE_CODE (decl
) == FUNCTION_DECL
);
1420 DECL_COMDAT (decl
) = 0;
1421 DECL_WEAK (decl
) = 0;
1422 DECL_EXTERNAL (decl
) = 0;
1423 DECL_VISIBILITY_SPECIFIED (decl
) = 0;
1424 DECL_VISIBILITY (decl
) = VISIBILITY_DEFAULT
;
1425 TREE_PUBLIC (decl
) = 0;
1426 DECL_DLLIMPORT_P (decl
) = 0;
1427 if (!DECL_RTL_SET_P (decl
))
1430 /* Update rtl flags. */
1431 make_decl_rtl (decl
);
1433 rtl
= DECL_RTL (decl
);
1437 symbol
= XEXP (rtl
, 0);
1438 if (GET_CODE (symbol
) != SYMBOL_REF
)
1441 SYMBOL_REF_WEAK (symbol
) = DECL_WEAK (decl
);
1444 /* Copy visibility from N.
1445 This is useful when THIS becomes a transparent alias of N. */
1448 symtab_node::copy_visibility_from (symtab_node
*n
)
1450 gcc_checking_assert (n
->weakref
== weakref
);
1453 for (unsigned i
= 0; iterate_direct_aliases (i
, ref
); i
++)
1455 struct symtab_node
*alias
= ref
->referring
;
1456 if (alias
->transparent_alias
)
1457 alias
->copy_visibility_from (n
);
1462 DECL_COMMON (decl
) = DECL_COMMON (n
->decl
);
1463 /* ADDRESSABLE flag is not defined for public symbols. */
1464 if (TREE_PUBLIC (decl
) && !TREE_PUBLIC (n
->decl
))
1465 TREE_ADDRESSABLE (decl
) = 1;
1466 TREE_STATIC (decl
) = TREE_STATIC (n
->decl
);
1468 else gcc_assert (TREE_CODE (decl
) == FUNCTION_DECL
);
1470 DECL_COMDAT (decl
) = DECL_COMDAT (n
->decl
);
1471 DECL_WEAK (decl
) = DECL_WEAK (n
->decl
);
1472 DECL_EXTERNAL (decl
) = DECL_EXTERNAL (n
->decl
);
1473 DECL_VISIBILITY_SPECIFIED (decl
) = DECL_VISIBILITY_SPECIFIED (n
->decl
);
1474 DECL_VISIBILITY (decl
) = DECL_VISIBILITY (n
->decl
);
1475 TREE_PUBLIC (decl
) = TREE_PUBLIC (n
->decl
);
1476 DECL_DLLIMPORT_P (decl
) = DECL_DLLIMPORT_P (n
->decl
);
1477 resolution
= n
->resolution
;
1478 set_comdat_group (n
->get_comdat_group ());
1479 call_for_symbol_and_aliases (symtab_node::set_section
,
1480 const_cast<char *>(n
->get_section ()), true);
1481 externally_visible
= n
->externally_visible
;
1482 if (!DECL_RTL_SET_P (decl
))
1485 /* Update rtl flags. */
1486 make_decl_rtl (decl
);
1488 rtx rtl
= DECL_RTL (decl
);
1492 rtx symbol
= XEXP (rtl
, 0);
1493 if (GET_CODE (symbol
) != SYMBOL_REF
)
1496 SYMBOL_REF_WEAK (symbol
) = DECL_WEAK (decl
);
1499 /* Walk the alias chain to return the symbol NODE is alias of.
1500 If NODE is not an alias, return NODE.
1501 Assumes NODE is known to be alias. */
1504 symtab_node::ultimate_alias_target_1 (enum availability
*availability
,
1507 bool transparent_p
= false;
1509 /* To determine visibility of the target, we follow ELF semantic of aliases.
1510 Here alias is an alternative assembler name of a given definition. Its
1511 availability prevails the availability of its target (i.e. static alias of
1512 weak definition is available.
1514 Transparent alias is just alternative name of a given symbol used within
1515 one compilation unit and is translated prior hitting the object file. It
1516 inherits the visibility of its target.
1517 Weakref is a different animal (and noweak definition is weak).
1519 If we ever get into supporting targets with different semantics, a target
1520 hook will be needed here. */
1524 transparent_p
= transparent_alias
;
1526 *availability
= get_availability (ref
);
1528 *availability
= AVAIL_NOT_AVAILABLE
;
1531 symtab_node
*node
= this;
1534 if (node
->alias
&& node
->analyzed
)
1535 node
= node
->get_alias_target ();
1538 if (!availability
|| (!transparent_p
&& node
->analyzed
))
1540 else if (node
->analyzed
&& !node
->transparent_alias
)
1541 *availability
= node
->get_availability (ref
);
1543 *availability
= AVAIL_NOT_AVAILABLE
;
1546 if (node
&& availability
&& transparent_p
1547 && node
->transparent_alias
)
1549 *availability
= node
->get_availability (ref
);
1550 transparent_p
= false;
1554 *availability
= AVAIL_NOT_AVAILABLE
;
1558 /* C++ FE sometimes change linkage flags after producing same body aliases.
1560 FIXME: C++ produce implicit aliases for virtual functions and vtables that
1561 are obviously equivalent. The way it is doing so is however somewhat
1562 kludgy and interferes with the visibility code. As a result we need to
1563 copy the visibility from the target to get things right. */
1566 symtab_node::fixup_same_cpp_alias_visibility (symtab_node
*target
)
1568 if (is_a
<cgraph_node
*> (this))
1570 DECL_DECLARED_INLINE_P (decl
)
1571 = DECL_DECLARED_INLINE_P (target
->decl
);
1572 DECL_DISREGARD_INLINE_LIMITS (decl
)
1573 = DECL_DISREGARD_INLINE_LIMITS (target
->decl
);
1575 /* FIXME: It is not really clear why those flags should not be copied for
1579 DECL_WEAK (decl
) = DECL_WEAK (target
->decl
);
1580 DECL_EXTERNAL (decl
) = DECL_EXTERNAL (target
->decl
);
1581 DECL_VISIBILITY (decl
) = DECL_VISIBILITY (target
->decl
);
1583 if (TREE_PUBLIC (decl
))
1587 DECL_EXTERNAL (decl
) = DECL_EXTERNAL (target
->decl
);
1588 DECL_COMDAT (decl
) = DECL_COMDAT (target
->decl
);
1589 group
= target
->get_comdat_group ();
1590 set_comdat_group (group
);
1591 if (group
&& !same_comdat_group
)
1592 add_to_same_comdat_group (target
);
1594 externally_visible
= target
->externally_visible
;
1597 /* Set section, do not recurse into aliases.
1598 When one wants to change section of a symbol and its aliases,
1602 symtab_node::set_section_for_node (const char *section
)
1604 const char *current
= get_section ();
1605 section_hash_entry
**slot
;
1607 if (current
== section
1608 || (current
&& section
1609 && !strcmp (current
, section
)))
1614 x_section
->ref_count
--;
1615 if (!x_section
->ref_count
)
1617 hashval_t hash
= htab_hash_string (x_section
->name
);
1618 slot
= symtab
->section_hash
->find_slot_with_hash (x_section
->name
,
1620 ggc_free (x_section
);
1621 symtab
->section_hash
->clear_slot (slot
);
1627 implicit_section
= false;
1630 if (!symtab
->section_hash
)
1631 symtab
->section_hash
= hash_table
<section_name_hasher
>::create_ggc (10);
1632 slot
= symtab
->section_hash
->find_slot_with_hash (section
,
1633 htab_hash_string (section
),
1636 x_section
= (section_hash_entry
*)*slot
;
1639 int len
= strlen (section
);
1640 *slot
= x_section
= ggc_cleared_alloc
<section_hash_entry
> ();
1641 x_section
->name
= ggc_vec_alloc
<char> (len
+ 1);
1642 memcpy (x_section
->name
, section
, len
+ 1);
1644 x_section
->ref_count
++;
1647 /* Worker for set_section. */
1650 symtab_node::set_section (symtab_node
*n
, void *s
)
1652 n
->set_section_for_node ((char *)s
);
1656 /* Set section of symbol and its aliases. */
1659 symtab_node::set_section (const char *section
)
1661 gcc_assert (!this->alias
|| !this->analyzed
);
1662 call_for_symbol_and_aliases
1663 (symtab_node::set_section
, const_cast<char *>(section
), true);
1666 /* Return the initialization priority. */
1669 symtab_node::get_init_priority ()
1671 if (!this->in_init_priority_hash
)
1672 return DEFAULT_INIT_PRIORITY
;
1674 symbol_priority_map
*h
= symtab
->init_priority_hash
->get (this);
1675 return h
? h
->init
: DEFAULT_INIT_PRIORITY
;
1678 /* Return the finalization priority. */
1681 cgraph_node::get_fini_priority ()
1683 if (!this->in_init_priority_hash
)
1684 return DEFAULT_INIT_PRIORITY
;
1685 symbol_priority_map
*h
= symtab
->init_priority_hash
->get (this);
1686 return h
? h
->fini
: DEFAULT_INIT_PRIORITY
;
1689 /* Return the initialization and finalization priority information for
1690 DECL. If there is no previous priority information, a freshly
1691 allocated structure is returned. */
1693 symbol_priority_map
*
1694 symtab_node::priority_info (void)
1696 if (!symtab
->init_priority_hash
)
1697 symtab
->init_priority_hash
= hash_map
<symtab_node
*, symbol_priority_map
>::create_ggc (13);
1700 symbol_priority_map
*h
1701 = &symtab
->init_priority_hash
->get_or_insert (this, &existed
);
1704 h
->init
= DEFAULT_INIT_PRIORITY
;
1705 h
->fini
= DEFAULT_INIT_PRIORITY
;
1706 in_init_priority_hash
= true;
1712 /* Set initialization priority to PRIORITY. */
1715 symtab_node::set_init_priority (priority_type priority
)
1717 symbol_priority_map
*h
;
1719 if (is_a
<cgraph_node
*> (this))
1720 gcc_assert (DECL_STATIC_CONSTRUCTOR (this->decl
));
1722 if (priority
== DEFAULT_INIT_PRIORITY
)
1724 gcc_assert (get_init_priority() == priority
);
1727 h
= priority_info ();
1731 /* Set finalization priority to PRIORITY. */
1734 cgraph_node::set_fini_priority (priority_type priority
)
1736 symbol_priority_map
*h
;
1738 gcc_assert (DECL_STATIC_DESTRUCTOR (this->decl
));
1740 if (priority
== DEFAULT_INIT_PRIORITY
)
1742 gcc_assert (get_fini_priority() == priority
);
1745 h
= priority_info ();
1749 /* Worker for symtab_resolve_alias. */
1752 symtab_node::set_implicit_section (symtab_node
*n
,
1753 void *data ATTRIBUTE_UNUSED
)
1755 n
->implicit_section
= true;
1759 /* Add reference recording that symtab node is alias of TARGET.
1760 The function can fail in the case of aliasing cycles; in this case
1761 it returns false. */
1764 symtab_node::resolve_alias (symtab_node
*target
, bool transparent
)
1768 gcc_assert (!analyzed
&& !vec_safe_length (ref_list
.references
));
1770 /* Never let cycles to creep into the symbol table alias references;
1771 those will make alias walkers to be infinite. */
1772 for (n
= target
; n
&& n
->alias
;
1773 n
= n
->analyzed
? n
->get_alias_target () : NULL
)
1776 if (is_a
<cgraph_node
*> (this))
1777 error ("function %q+D part of alias cycle", decl
);
1778 else if (is_a
<varpool_node
*> (this))
1779 error ("variable %q+D part of alias cycle", decl
);
1786 /* "analyze" the node - i.e. mark the reference. */
1790 transparent
|= transparent_alias
;
1791 transparent_alias
= transparent
;
1793 while (target
->transparent_alias
&& target
->analyzed
)
1794 target
= target
->get_alias_target ();
1795 create_reference (target
, IPA_REF_ALIAS
, NULL
);
1797 /* Add alias into the comdat group of its target unless it is already there. */
1798 if (same_comdat_group
)
1799 remove_from_same_comdat_group ();
1800 set_comdat_group (NULL
);
1801 if (target
->get_comdat_group ())
1802 add_to_same_comdat_group (target
);
1804 if ((get_section () != target
->get_section ()
1805 || target
->get_comdat_group ()) && get_section () && !implicit_section
)
1807 error ("section of alias %q+D must match section of its target", decl
);
1809 call_for_symbol_and_aliases (symtab_node::set_section
,
1810 const_cast<char *>(target
->get_section ()), true);
1811 if (target
->implicit_section
)
1812 call_for_symbol_and_aliases (set_implicit_section
, NULL
, true);
1814 /* Alias targets become redundant after alias is resolved into an reference.
1815 We do not want to keep it around or we would have to mind updating them
1816 when renaming symbols. */
1817 alias_target
= NULL
;
1819 if (!transparent
&& cpp_implicit_alias
&& symtab
->state
>= CONSTRUCTION
)
1820 fixup_same_cpp_alias_visibility (target
);
1822 /* If alias has address taken, so does the target. */
1824 target
->ultimate_alias_target ()->address_taken
= true;
1826 /* All non-transparent aliases of THIS are now in fact aliases of TARGET.
1827 If alias is transparent, also all transparent aliases of THIS are now
1829 Also merge same comdat group lists. */
1831 for (unsigned i
= 0; iterate_direct_aliases (i
, ref
);)
1833 struct symtab_node
*alias_alias
= ref
->referring
;
1834 if (alias_alias
->get_comdat_group ())
1836 alias_alias
->remove_from_same_comdat_group ();
1837 alias_alias
->set_comdat_group (NULL
);
1838 if (target
->get_comdat_group ())
1839 alias_alias
->add_to_same_comdat_group (target
);
1841 if ((!alias_alias
->transparent_alias
1842 && !alias_alias
->symver
)
1845 alias_alias
->remove_all_references ();
1846 alias_alias
->create_reference (target
, IPA_REF_ALIAS
, NULL
);
1853 /* Worker searching noninterposable alias. */
1856 symtab_node::noninterposable_alias (symtab_node
*node
, void *data
)
1858 if (!node
->transparent_alias
&& decl_binds_to_current_def_p (node
->decl
))
1860 symtab_node
*fn
= node
->ultimate_alias_target ();
1862 /* Ensure that the alias is well formed this may not be the case
1863 of user defined aliases and currently it is not always the case
1864 of C++ same body aliases (that is a bug). */
1865 if (TREE_TYPE (node
->decl
) != TREE_TYPE (fn
->decl
)
1866 || DECL_CONTEXT (node
->decl
) != DECL_CONTEXT (fn
->decl
)
1867 || (TREE_CODE (node
->decl
) == FUNCTION_DECL
1868 && flags_from_decl_or_type (node
->decl
)
1869 != flags_from_decl_or_type (fn
->decl
))
1870 || DECL_ATTRIBUTES (node
->decl
) != DECL_ATTRIBUTES (fn
->decl
))
1872 *(symtab_node
**)data
= node
;
1878 /* If node cannot be overwriten by static or dynamic linker to point to
1879 different definition, return NODE. Otherwise look for alias with such
1880 property and if none exists, introduce new one. */
1883 symtab_node::noninterposable_alias (void)
1886 symtab_node
*new_node
= NULL
;
1888 /* First try to look up existing alias or base object
1889 (if that is already non-overwritable). */
1890 symtab_node
*node
= ultimate_alias_target ();
1891 gcc_assert (!node
->alias
&& !node
->weakref
);
1892 node
->call_for_symbol_and_aliases (symtab_node::noninterposable_alias
,
1893 (void *)&new_node
, true);
1897 /* If aliases aren't supported by the assembler, fail. */
1898 if (!TARGET_SUPPORTS_ALIASES
)
1901 /* Otherwise create a new one. */
1902 new_decl
= copy_node (node
->decl
);
1903 DECL_DLLIMPORT_P (new_decl
) = 0;
1904 tree name
= clone_function_name (node
->decl
, "localalias");
1907 unsigned long num
= 0;
1908 /* In the rare case we already have a localalias, but the above
1909 node->call_for_symbol_and_aliases call didn't find any suitable,
1910 iterate until we find one not used yet. */
1911 while (symtab_node::get_for_asmname (name
))
1912 name
= clone_function_name (node
->decl
, "localalias", num
++);
1914 DECL_NAME (new_decl
) = name
;
1915 if (TREE_CODE (new_decl
) == FUNCTION_DECL
)
1916 DECL_STRUCT_FUNCTION (new_decl
) = NULL
;
1917 DECL_INITIAL (new_decl
) = NULL
;
1918 SET_DECL_ASSEMBLER_NAME (new_decl
, DECL_NAME (new_decl
));
1919 SET_DECL_RTL (new_decl
, NULL
);
1921 /* Update the properties. */
1922 DECL_EXTERNAL (new_decl
) = 0;
1923 TREE_PUBLIC (new_decl
) = 0;
1924 DECL_COMDAT (new_decl
) = 0;
1925 DECL_WEAK (new_decl
) = 0;
1927 /* Since the aliases can be added to vtables, keep DECL_VIRTUAL flag. */
1928 DECL_VIRTUAL_P (new_decl
) = DECL_VIRTUAL_P (node
->decl
);
1929 if (TREE_CODE (new_decl
) == FUNCTION_DECL
)
1931 DECL_STATIC_CONSTRUCTOR (new_decl
) = 0;
1932 DECL_STATIC_DESTRUCTOR (new_decl
) = 0;
1933 new_node
= cgraph_node::create_alias (new_decl
, node
->decl
);
1935 cgraph_node
*new_cnode
= dyn_cast
<cgraph_node
*> (new_node
),
1936 *cnode
= dyn_cast
<cgraph_node
*> (node
);
1938 new_cnode
->unit_id
= cnode
->unit_id
;
1939 new_cnode
->merged_comdat
= cnode
->merged_comdat
;
1940 new_cnode
->merged_extern_inline
= cnode
->merged_extern_inline
;
1944 TREE_READONLY (new_decl
) = TREE_READONLY (node
->decl
);
1945 DECL_INITIAL (new_decl
) = error_mark_node
;
1946 new_node
= varpool_node::create_alias (new_decl
, node
->decl
);
1948 new_node
->resolve_alias (node
);
1949 gcc_assert (decl_binds_to_current_def_p (new_decl
)
1950 && targetm
.binds_local_p (new_decl
));
1954 /* Return true if symtab node and TARGET represents
1955 semantically equivalent symbols. */
1958 symtab_node::semantically_equivalent_p (symtab_node
*target
)
1960 enum availability avail
;
1964 /* Equivalent functions are equivalent. */
1965 if (decl
== target
->decl
)
1968 /* If symbol is not overwritable by different implementation,
1969 walk to the base object it defines. */
1970 ba
= ultimate_alias_target (&avail
);
1971 if (avail
>= AVAIL_AVAILABLE
)
1978 bb
= target
->ultimate_alias_target (&avail
);
1979 if (avail
>= AVAIL_AVAILABLE
)
1989 /* Classify symbol symtab node for partitioning. */
1991 enum symbol_partitioning_class
1992 symtab_node::get_partitioning_class (void)
1994 /* Inline clones are always duplicated.
1995 This include external declarations. */
1996 cgraph_node
*cnode
= dyn_cast
<cgraph_node
*> (this);
1998 if (DECL_ABSTRACT_P (decl
))
1999 return SYMBOL_EXTERNAL
;
2001 if (cnode
&& cnode
->inlined_to
)
2002 return SYMBOL_DUPLICATE
;
2004 /* Transparent aliases are always duplicated. */
2005 if (transparent_alias
)
2006 return definition
? SYMBOL_DUPLICATE
: SYMBOL_EXTERNAL
;
2008 /* External declarations are external. */
2009 if (DECL_EXTERNAL (decl
))
2010 return SYMBOL_EXTERNAL
;
2012 /* Even static aliases of external functions as external. Those can happen
2013 when COMDAT got resolved to non-IL implementation. */
2014 if (alias
&& DECL_EXTERNAL (ultimate_alias_target ()->decl
))
2015 return SYMBOL_EXTERNAL
;
2017 if (varpool_node
*vnode
= dyn_cast
<varpool_node
*> (this))
2019 if (alias
&& definition
&& !ultimate_alias_target ()->definition
)
2020 return SYMBOL_EXTERNAL
;
2021 /* Constant pool references use local symbol names that cannot
2022 be promoted global. We should never put into a constant pool
2023 objects that cannot be duplicated across partitions. */
2024 if (DECL_IN_CONSTANT_POOL (decl
))
2025 return SYMBOL_DUPLICATE
;
2026 if (DECL_HARD_REGISTER (decl
))
2027 return SYMBOL_DUPLICATE
;
2028 gcc_checking_assert (vnode
->definition
);
2030 /* Functions that are cloned may stay in callgraph even if they are unused.
2031 Handle them as external; compute_ltrans_boundary take care to make
2032 proper things to happen (i.e. to make them appear in the boundary but
2033 with body streamed, so clone can me materialized). */
2034 else if (!dyn_cast
<cgraph_node
*> (this)->function_symbol ()->definition
)
2035 return SYMBOL_EXTERNAL
;
2037 /* Linker discardable symbols are duplicated to every use unless they are
2039 if (DECL_ONE_ONLY (decl
)
2042 && !used_from_object_file_p ())
2043 return SYMBOL_DUPLICATE
;
2045 return SYMBOL_PARTITION
;
2048 /* Return true when symbol is known to be non-zero. */
2051 symtab_node::nonzero_address ()
2053 /* Weakrefs may be NULL when their target is not defined. */
2054 if (alias
&& weakref
)
2058 symtab_node
*target
= ultimate_alias_target ();
2060 if (target
->alias
&& target
->weakref
)
2062 /* We cannot recurse to target::nonzero. It is possible that the
2063 target is used only via the alias.
2064 We may walk references and look for strong use, but we do not know
2065 if this strong use will survive to final binary, so be
2067 ??? Maybe we could do the lookup during late optimization that
2068 could be useful to eliminate the NULL pointer checks in LTO
2070 if (target
->definition
&& !DECL_EXTERNAL (target
->decl
))
2072 if (target
->resolution
!= LDPR_UNKNOWN
2073 && target
->resolution
!= LDPR_UNDEF
2074 && !target
->can_be_discarded_p ()
2075 && flag_delete_null_pointer_checks
)
2083 /* With !flag_delete_null_pointer_checks we assume that symbols may
2084 bind to NULL. This is on by default on embedded targets only.
2086 Otherwise all non-WEAK symbols must be defined and thus non-NULL or
2087 linking fails. Important case of WEAK we want to do well are comdats,
2088 which also must be defined somewhere.
2090 When parsing, beware the cases when WEAK attribute is added later. */
2091 if ((!DECL_WEAK (decl
) || DECL_COMDAT (decl
))
2092 && flag_delete_null_pointer_checks
)
2094 refuse_visibility_changes
= true;
2098 /* If target is defined and not extern, we know it will be
2099 output and thus it will bind to non-NULL.
2100 Play safe for flag_delete_null_pointer_checks where weak definition may
2101 be re-defined by NULL. */
2102 if (definition
&& !DECL_EXTERNAL (decl
)
2103 && (flag_delete_null_pointer_checks
|| !DECL_WEAK (decl
)))
2105 if (!DECL_WEAK (decl
))
2106 refuse_visibility_changes
= true;
2110 /* As the last resort, check the resolution info. */
2111 if (resolution
!= LDPR_UNKNOWN
2112 && resolution
!= LDPR_UNDEF
2113 && !can_be_discarded_p ()
2114 && flag_delete_null_pointer_checks
)
2119 /* Return 0 if symbol is known to have different address than S2,
2120 Return 1 if symbol is known to have same address as S2,
2121 return -1 otherwise.
2123 If MEMORY_ACCESSED is true, assume that both memory pointer to THIS
2124 and S2 is going to be accessed. This eliminates the situations when
2125 either THIS or S2 is NULL and is useful for comparing bases when deciding
2126 about memory aliasing. */
2128 symtab_node::equal_address_to (symtab_node
*s2
, bool memory_accessed
)
2130 enum availability avail1
, avail2
;
2132 /* A Shortcut: equivalent symbols are always equivalent. */
2136 /* Unwind transparent aliases first; those are always equal to their
2138 if (this->transparent_alias
&& this->analyzed
)
2139 return this->get_alias_target ()->equal_address_to (s2
);
2140 while (s2
->transparent_alias
&& s2
->analyzed
)
2141 s2
= s2
->get_alias_target();
2146 /* For non-interposable aliases, lookup and compare their actual definitions.
2147 Also check if the symbol needs to bind to given definition. */
2148 symtab_node
*rs1
= ultimate_alias_target (&avail1
);
2149 symtab_node
*rs2
= s2
->ultimate_alias_target (&avail2
);
2150 bool binds_local1
= rs1
->analyzed
&& decl_binds_to_current_def_p (this->decl
);
2151 bool binds_local2
= rs2
->analyzed
&& decl_binds_to_current_def_p (s2
->decl
);
2152 bool really_binds_local1
= binds_local1
;
2153 bool really_binds_local2
= binds_local2
;
2155 /* Addresses of vtables and virtual functions cannot be used by user
2156 code and are used only within speculation. In this case we may make
2157 symbol equivalent to its alias even if interposition may break this
2158 rule. Doing so will allow us to turn speculative inlining into
2159 non-speculative more aggressively. */
2160 if (DECL_VIRTUAL_P (this->decl
) && avail1
>= AVAIL_AVAILABLE
)
2161 binds_local1
= true;
2162 if (DECL_VIRTUAL_P (s2
->decl
) && avail2
>= AVAIL_AVAILABLE
)
2163 binds_local2
= true;
2165 /* If both definitions are available we know that even if they are bound
2166 to other unit they must be defined same way and therefore we can use
2167 equivalence test. */
2168 if (rs1
!= rs2
&& avail1
>= AVAIL_AVAILABLE
&& avail2
>= AVAIL_AVAILABLE
)
2169 binds_local1
= binds_local2
= true;
2171 if (binds_local1
&& binds_local2
&& rs1
== rs2
)
2173 /* We made use of the fact that alias is not weak. */
2175 refuse_visibility_changes
= true;
2177 s2
->refuse_visibility_changes
= true;
2181 /* If both symbols may resolve to NULL, we cannot really prove them
2183 if (!memory_accessed
&& !nonzero_address () && !s2
->nonzero_address ())
2186 /* Except for NULL, functions and variables never overlap. */
2187 if (TREE_CODE (decl
) != TREE_CODE (s2
->decl
))
2190 /* If one of the symbols is unresolved alias, punt. */
2191 if (rs1
->alias
|| rs2
->alias
)
2194 /* If we have a non-interposale definition of at least one of the symbols
2195 and the other symbol is different, we know other unit cannot interpose
2196 it to the first symbol; all aliases of the definition needs to be
2197 present in the current unit. */
2198 if (((really_binds_local1
|| really_binds_local2
)
2199 /* If we have both definitions and they are different, we know they
2200 will be different even in units they binds to. */
2201 || (binds_local1
&& binds_local2
))
2204 /* We make use of the fact that one symbol is not alias of the other
2205 and that the definition is non-interposable. */
2206 refuse_visibility_changes
= true;
2207 s2
->refuse_visibility_changes
= true;
2208 rs1
->refuse_visibility_changes
= true;
2209 rs2
->refuse_visibility_changes
= true;
2213 /* TODO: Alias oracle basically assume that addresses of global variables
2214 are different unless they are declared as alias of one to another while
2215 the code folding comparisons doesn't.
2216 We probably should be consistent and use this fact here, too, but for
2217 the moment return false only when we are called from the alias oracle. */
2219 return memory_accessed
&& rs1
!= rs2
? 0 : -1;
2222 /* Worker for call_for_symbol_and_aliases. */
2225 symtab_node::call_for_symbol_and_aliases_1 (bool (*callback
) (symtab_node
*,
2228 bool include_overwritable
)
2231 FOR_EACH_ALIAS (this, ref
)
2233 symtab_node
*alias
= ref
->referring
;
2234 if (include_overwritable
2235 || alias
->get_availability () > AVAIL_INTERPOSABLE
)
2236 if (alias
->call_for_symbol_and_aliases (callback
, data
,
2237 include_overwritable
))
2243 /* Return true if address of N is possibly compared. */
2246 address_matters_1 (symtab_node
*n
, void *)
2248 struct ipa_ref
*ref
;
2250 if (!n
->address_can_be_compared_p ())
2252 if (n
->externally_visible
|| n
->force_output
)
2255 for (unsigned int i
= 0; n
->iterate_referring (i
, ref
); i
++)
2256 if (ref
->address_matters_p ())
2261 /* Return true if symbol's address may possibly be compared to other
2262 symbol's address. */
2265 symtab_node::address_matters_p ()
2267 gcc_assert (!alias
);
2268 return call_for_symbol_and_aliases (address_matters_1
, NULL
, true);
2271 /* Return true if symbol's alignment may be increased. */
2274 symtab_node::can_increase_alignment_p (void)
2276 symtab_node
*target
= ultimate_alias_target ();
2278 /* For now support only variables. */
2282 /* With -fno-toplevel-reorder we may have already output the constant. */
2283 if (TREE_ASM_WRITTEN (target
->decl
))
2286 /* If target is already placed in an anchor, we cannot touch its
2288 if (DECL_RTL_SET_P (target
->decl
)
2289 && MEM_P (DECL_RTL (target
->decl
))
2290 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (DECL_RTL (target
->decl
), 0)))
2293 /* Constant pool entries may be shared. */
2294 if (DECL_IN_CONSTANT_POOL (target
->decl
))
2297 /* We cannot change alignment of symbols that may bind to symbols
2298 in other translation unit that may contain a definition with lower
2300 if (!decl_binds_to_current_def_p (decl
))
2303 /* When compiling partition, be sure the symbol is not output by other
2306 && (target
->in_other_partition
2307 || target
->get_partitioning_class () == SYMBOL_DUPLICATE
))
2310 /* Do not override the alignment as specified by the ABI when the used
2311 attribute is set. */
2312 if (DECL_PRESERVE_P (decl
) || DECL_PRESERVE_P (target
->decl
))
2315 /* Do not override explicit alignment set by the user when an explicit
2316 section name is also used. This is a common idiom used by many
2317 software projects. */
2318 if (DECL_SECTION_NAME (target
->decl
) != NULL
&& !target
->implicit_section
)
2324 /* Worker for symtab_node::increase_alignment. */
2327 increase_alignment_1 (symtab_node
*n
, void *v
)
2329 unsigned int align
= (size_t)v
;
2330 if (DECL_ALIGN (n
->decl
) < align
2331 && n
->can_increase_alignment_p ())
2333 SET_DECL_ALIGN (n
->decl
, align
);
2334 DECL_USER_ALIGN (n
->decl
) = 1;
2339 /* Increase alignment of THIS to ALIGN. */
2342 symtab_node::increase_alignment (unsigned int align
)
2344 gcc_assert (can_increase_alignment_p () && align
<= MAX_OFILE_ALIGNMENT
);
2345 ultimate_alias_target()->call_for_symbol_and_aliases (increase_alignment_1
,
2346 (void *)(size_t) align
,
2348 gcc_assert (DECL_ALIGN (decl
) >= align
);
2351 /* Helper for symtab_node::definition_alignment. */
2354 get_alignment_1 (symtab_node
*n
, void *v
)
2356 *((unsigned int *)v
) = MAX (*((unsigned int *)v
), DECL_ALIGN (n
->decl
));
2360 /* Return desired alignment of the definition. This is NOT alignment useful
2361 to access THIS, because THIS may be interposable and DECL_ALIGN should
2362 be used instead. It however must be guaranteed when output definition
2366 symtab_node::definition_alignment ()
2368 unsigned int align
= 0;
2369 gcc_assert (!alias
);
2370 call_for_symbol_and_aliases (get_alignment_1
, &align
, true);
2374 /* Return symbol used to separate symbol name from suffix. */
2377 symbol_table::symbol_suffix_separator ()
2379 #ifndef NO_DOT_IN_LABEL
2381 #elif !defined NO_DOLLAR_IN_LABEL
2388 /* Return true when references to this symbol from REF must bind to current
2389 definition in final executable. */
2392 symtab_node::binds_to_current_def_p (symtab_node
*ref
)
2396 if (transparent_alias
)
2398 && get_alias_target()->binds_to_current_def_p (ref
);
2399 cgraph_node
*cnode
= dyn_cast
<cgraph_node
*> (this);
2400 if (cnode
&& cnode
->ifunc_resolver
)
2402 if (decl_binds_to_current_def_p (decl
))
2405 /* Inline clones always binds locally. */
2406 if (cnode
&& cnode
->inlined_to
)
2409 if (DECL_EXTERNAL (decl
))
2412 gcc_assert (externally_visible
);
2416 cgraph_node
*cref
= dyn_cast
<cgraph_node
*> (ref
);
2418 ref
= cref
->inlined_to
;
2421 /* If this is a reference from symbol itself and there are no aliases, we
2422 may be sure that the symbol was not interposed by something else because
2423 the symbol itself would be unreachable otherwise. This is important
2424 to optimize recursive functions well.
2426 This assumption may be broken by inlining: if symbol is interposable
2427 but the body is available (i.e. declared inline), inliner may make
2428 the body reachable even with interposition. */
2429 if (this == ref
&& !has_aliases_p ()
2431 || symtab
->state
>= IPA_SSA_AFTER_INLINING
2432 || get_availability () >= AVAIL_INTERPOSABLE
))
2436 /* References within one comdat group are always bound in a group. */
2438 && symtab
->state
>= IPA_SSA_AFTER_INLINING
2439 && get_comdat_group ()
2440 && get_comdat_group () == ref
->get_comdat_group ())
2446 /* Return true if symbol should be output to the symbol table. */
2449 symtab_node::output_to_lto_symbol_table_p (void)
2451 /* Only externally visible symbols matter. */
2452 if (!TREE_PUBLIC (decl
))
2454 if (!real_symbol_p ())
2456 /* FIXME: variables probably should not be considered as real symbols at
2458 if (VAR_P (decl
) && DECL_HARD_REGISTER (decl
))
2460 if (TREE_CODE (decl
) == FUNCTION_DECL
&& !definition
2461 && fndecl_built_in_p (decl
))
2463 /* Builtins like those for most math functions have actual implementations
2464 in libraries so make sure to output references into the symbol table to
2465 make those libraries referenced. Note this is incomplete handling for
2466 now and only covers math functions. */
2467 if (builtin_with_linkage_p (decl
))
2473 /* We have real symbol that should be in symbol table. However try to trim
2474 down the references to libraries bit more because linker will otherwise
2475 bring unnecessary object files into the final link.
2476 FIXME: The following checks can easily be confused i.e. by self recursive
2477 function or self-referring variable. */
2479 /* We keep external functions in symtab for sake of inlining
2480 and devirtualization. We do not want to see them in symbol table as
2481 references unless they are really used. */
2482 cgraph_node
*cnode
= dyn_cast
<cgraph_node
*> (this);
2483 if (cnode
&& (!definition
|| DECL_EXTERNAL (decl
))
2487 /* Ignore all references from external vars initializers - they are not really
2488 part of the compilation unit until they are used by folding. Some symbols,
2489 like references to external construction vtables cannot be referred to at
2490 all. We decide this at can_refer_decl_in_current_unit_p. */
2491 if (!definition
|| DECL_EXTERNAL (decl
))
2494 struct ipa_ref
*ref
;
2495 for (i
= 0; iterate_referring (i
, ref
); i
++)
2497 if (ref
->use
== IPA_REF_ALIAS
)
2499 if (is_a
<cgraph_node
*> (ref
->referring
))
2501 if (!DECL_EXTERNAL (ref
->referring
->decl
))