2 Copyright (C) 2003-2015 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 /* This file implements two related passes:
22 - pass_data_ipa_function_and_variable_visibility run just after
23 symbol table, references and callgraph are built
25 - pass_data_ipa_function_and_variable_visibility run as first
26 proper IPA pass (that is after early optimization, or, (with LTO)
27 as a first pass done at link-time.
29 Purpose of both passes is to set correctly visibility properties
30 of all symbols. This includes:
32 - Symbol privatization:
34 Some symbols that are declared public by frontend may be
35 turned local (either by -fwhole-program flag, by linker plugin feedback
38 - Discovery of local functions:
40 A local function is one whose calls can occur only in the current
41 compilation unit and all its calls are explicit, so we can change
42 its calling convention. We simply mark all static functions whose
43 address is not taken as local.
45 externally_visible flag is set for symbols that can not be privatized.
46 For privatized symbols we clear TREE_PUBLIC flag and dismantle comdat
49 - Dismantling of comdat groups:
51 Comdat group represent a section that may be replaced by linker by
52 a different copy of the same section from other unit.
53 If we have resolution information (from linker plugin) and we know that
54 a given comdat gorup is prevailing, we can dismantle it and turn symbols
55 into normal symbols. If the resolution information says that the
56 section was previaled by copy from non-LTO code, we can also dismantle
57 it and turn all symbols into external.
61 Some symbols can be interposed by dynamic linker. Refering to these
62 symbols is expensive, since it needs to be overwritable by the dynamic
63 linker. In some cases we know that the interposition does not change
64 semantic and we can always refer to a local copy (as in the case of
65 inline function). In this case we produce a local alias and redirect
68 TODO: This should be done for references, too.
70 - Removal of static ocnstructors and destructors that have no side effects.
72 - Regularization of several oddities introduced by frontends that may
73 be impractical later in the optimization queue. */
77 #include "coretypes.h"
81 #include "gimple-expr.h"
82 #include "tree-pass.h"
87 /* Return true when NODE can not be local. Worker for cgraph_local_node_p. */
90 non_local_p (struct cgraph_node
*node
, void *data ATTRIBUTE_UNUSED
)
92 return !(node
->only_called_directly_or_aliased_p ()
93 /* i386 would need update to output thunk with locak calling
95 && !node
->thunk
.thunk_p
97 && !DECL_EXTERNAL (node
->decl
)
98 && !node
->externally_visible
99 && !node
->used_from_other_partition
100 && !node
->in_other_partition
);
103 /* Return true when function can be marked local. */
106 cgraph_node::local_p (void)
108 cgraph_node
*n
= ultimate_alias_target ();
110 if (n
->thunk
.thunk_p
)
111 return n
->callees
->callee
->local_p ();
112 return !n
->call_for_symbol_thunks_and_aliases (non_local_p
,
117 /* A helper for comdat_can_be_unshared_p. */
120 comdat_can_be_unshared_p_1 (symtab_node
*node
)
122 if (!node
->externally_visible
)
124 if (node
->address_can_be_compared_p ())
128 for (unsigned int i
= 0; node
->iterate_referring (i
, ref
); i
++)
129 if (ref
->address_matters_p ())
133 /* If the symbol is used in some weird way, better to not touch it. */
134 if (node
->force_output
)
137 /* Explicit instantiations needs to be output when possibly
139 if (node
->forced_by_abi
140 && TREE_PUBLIC (node
->decl
)
141 && (node
->resolution
!= LDPR_PREVAILING_DEF_IRONLY
142 && !flag_whole_program
))
145 /* Non-readonly and volatile variables can not be duplicated. */
146 if (is_a
<varpool_node
*> (node
)
147 && (!TREE_READONLY (node
->decl
)
148 || TREE_THIS_VOLATILE (node
->decl
)))
153 /* COMDAT functions must be shared only if they have address taken,
154 otherwise we can produce our own private implementation with
156 Return true when turning COMDAT functoin static can not lead to wrong
157 code when the resulting object links with a library defining same COMDAT.
159 Virtual functions do have their addresses taken from the vtables,
160 but in C++ there is no way to compare their addresses for equality. */
163 comdat_can_be_unshared_p (symtab_node
*node
)
165 if (!comdat_can_be_unshared_p_1 (node
))
167 if (node
->same_comdat_group
)
171 /* If more than one function is in the same COMDAT group, it must
172 be shared even if just one function in the comdat group has
174 for (next
= node
->same_comdat_group
;
175 next
!= node
; next
= next
->same_comdat_group
)
176 if (!comdat_can_be_unshared_p_1 (next
))
182 /* Return true when function NODE should be considered externally visible. */
185 cgraph_externally_visible_p (struct cgraph_node
*node
,
188 while (node
->transparent_alias
&& node
->definition
)
189 node
= node
->get_alias_target ();
190 if (!node
->definition
)
192 if (!TREE_PUBLIC (node
->decl
)
193 || DECL_EXTERNAL (node
->decl
))
196 /* Do not try to localize built-in functions yet. One of problems is that we
197 end up mangling their asm for WHOPR that makes it impossible to call them
198 using the implicit built-in declarations anymore. Similarly this enables
199 us to remove them as unreachable before actual calls may appear during
200 expansion or folding. */
201 if (DECL_BUILT_IN (node
->decl
))
204 /* If linker counts on us, we must preserve the function. */
205 if (node
->used_from_object_file_p ())
207 if (DECL_PRESERVE_P (node
->decl
))
209 if (lookup_attribute ("externally_visible",
210 DECL_ATTRIBUTES (node
->decl
)))
212 if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
213 && lookup_attribute ("dllexport",
214 DECL_ATTRIBUTES (node
->decl
)))
216 if (node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
)
218 /* When doing LTO or whole program, we can bring COMDAT functoins static.
219 This improves code quality and we know we will duplicate them at most twice
220 (in the case that we are not using plugin and link with object file
221 implementing same COMDAT) */
222 if (((in_lto_p
|| whole_program
) && !flag_incremental_link
)
223 && DECL_COMDAT (node
->decl
)
224 && comdat_can_be_unshared_p (node
))
227 /* When doing link time optimizations, hidden symbols become local. */
228 if ((in_lto_p
&& !flag_incremental_link
)
229 && (DECL_VISIBILITY (node
->decl
) == VISIBILITY_HIDDEN
230 || DECL_VISIBILITY (node
->decl
) == VISIBILITY_INTERNAL
)
231 /* Be sure that node is defined in IR file, not in other object
232 file. In that case we don't set used_from_other_object_file. */
235 else if (!whole_program
)
238 if (MAIN_NAME_P (DECL_NAME (node
->decl
)))
241 if (node
->instrumentation_clone
242 && MAIN_NAME_P (DECL_NAME (node
->orig_decl
)))
248 /* Return true when variable should be considered externally visible. */
251 varpool_node::externally_visible_p (void)
253 while (transparent_alias
&& definition
)
254 return get_alias_target ()->externally_visible_p ();
255 if (DECL_EXTERNAL (decl
))
258 if (!TREE_PUBLIC (decl
))
261 /* If linker counts on us, we must preserve the function. */
262 if (used_from_object_file_p ())
265 /* Bringing TLS variables local may cause dynamic linker failures
266 on limits of static TLS vars. */
267 if (DECL_THREAD_LOCAL_P (decl
)
268 && (DECL_TLS_MODEL (decl
) != TLS_MODEL_EMULATED
269 && DECL_TLS_MODEL (decl
) != TLS_MODEL_INITIAL_EXEC
))
272 if (DECL_HARD_REGISTER (decl
))
274 if (DECL_PRESERVE_P (decl
))
276 if (lookup_attribute ("externally_visible",
277 DECL_ATTRIBUTES (decl
)))
279 if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
280 && lookup_attribute ("dllexport",
281 DECL_ATTRIBUTES (decl
)))
284 /* See if we have linker information about symbol not being used or
285 if we need to make guess based on the declaration.
287 Even if the linker clams the symbol is unused, never bring internal
288 symbols that are declared by user as used or externally visible.
289 This is needed for i.e. references from asm statements. */
290 if (used_from_object_file_p ())
292 if (resolution
== LDPR_PREVAILING_DEF_IRONLY
)
295 /* As a special case, the COMDAT virtual tables can be unshared.
296 In LTO mode turn vtables into static variables. The variable is readonly,
297 so this does not enable more optimization, but referring static var
298 is faster for dynamic linking. Also this match logic hidding vtables
299 from LTO symbol tables. */
300 if (((in_lto_p
|| flag_whole_program
) && !flag_incremental_link
)
301 && DECL_COMDAT (decl
)
302 && comdat_can_be_unshared_p (this))
305 /* When doing link time optimizations, hidden symbols become local. */
306 if (in_lto_p
&& !flag_incremental_link
307 && (DECL_VISIBILITY (decl
) == VISIBILITY_HIDDEN
308 || DECL_VISIBILITY (decl
) == VISIBILITY_INTERNAL
)
309 /* Be sure that node is defined in IR file, not in other object
310 file. In that case we don't set used_from_other_object_file. */
313 else if (!flag_whole_program
)
316 /* Do not attempt to privatize COMDATS by default.
317 This would break linking with C++ libraries sharing
320 FIXME: We can do so for readonly vars with no address taken and
321 possibly also for vtables since no direct pointer comparsion is done.
322 It might be interesting to do so to reduce linking overhead. */
323 if (DECL_COMDAT (decl
) || DECL_WEAK (decl
))
328 /* Return true if reference to NODE can be replaced by a local alias.
329 Local aliases save dynamic linking overhead and enable more optimizations.
333 can_replace_by_local_alias (symtab_node
*node
)
335 #ifndef ASM_OUTPUT_DEF
336 /* If aliases aren't supported, we can't do replacement. */
339 /* Weakrefs have a reason to be non-local. Be sure we do not replace
341 while (node
->transparent_alias
&& node
->definition
&& !node
->weakref
)
342 node
= node
->get_alias_target ();
346 return (node
->get_availability () > AVAIL_INTERPOSABLE
347 && !decl_binds_to_current_def_p (node
->decl
)
348 && !node
->can_be_discarded_p ());
351 /* Return true if we can replace reference to NODE by local alias
352 within a virtual table. Generally we can replace function pointers
353 and virtual table pointers. */
356 can_replace_by_local_alias_in_vtable (symtab_node
*node
)
358 if (is_a
<varpool_node
*> (node
)
359 && !DECL_VIRTUAL_P (node
->decl
))
361 return can_replace_by_local_alias (node
);
364 /* walk_tree callback that rewrites initializer references. */
367 update_vtable_references (tree
*tp
, int *walk_subtrees
,
368 void *data ATTRIBUTE_UNUSED
)
370 if (TREE_CODE (*tp
) == VAR_DECL
371 || TREE_CODE (*tp
) == FUNCTION_DECL
)
373 if (can_replace_by_local_alias_in_vtable (symtab_node::get (*tp
)))
374 *tp
= symtab_node::get (*tp
)->noninterposable_alias ()->decl
;
377 else if (IS_TYPE_OR_DECL_P (*tp
))
382 /* In LTO we can remove COMDAT groups and weak symbols.
383 Either turn them into normal symbols or external symbol depending on
387 update_visibility_by_resolution_info (symtab_node
* node
)
391 if (!node
->externally_visible
392 || (!DECL_WEAK (node
->decl
) && !DECL_ONE_ONLY (node
->decl
))
393 || node
->resolution
== LDPR_UNKNOWN
)
396 define
= (node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
397 || node
->resolution
== LDPR_PREVAILING_DEF
398 || node
->resolution
== LDPR_UNDEF
399 || node
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
);
401 /* The linker decisions ought to agree in the whole group. */
402 if (node
->same_comdat_group
)
403 for (symtab_node
*next
= node
->same_comdat_group
;
404 next
!= node
; next
= next
->same_comdat_group
)
406 if (!next
->externally_visible
|| next
->transparent_alias
)
410 = define
== (next
->resolution
== LDPR_PREVAILING_DEF_IRONLY
411 || next
->resolution
== LDPR_PREVAILING_DEF
412 || next
->resolution
== LDPR_UNDEF
413 || next
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
);
414 gcc_assert (in_lto_p
|| same_def
);
419 if (node
->same_comdat_group
)
420 for (symtab_node
*next
= node
->same_comdat_group
;
421 next
!= node
; next
= next
->same_comdat_group
)
423 /* During incremental linking we need to keep symbol weak for future
424 linking. We can still drop definition if we know non-LTO world
426 if (!flag_incremental_link
)
428 DECL_WEAK (next
->decl
) = false;
429 next
->set_comdat_group (NULL
);
433 if (next
->externally_visible
)
434 DECL_EXTERNAL (next
->decl
) = true;
435 next
->set_comdat_group (NULL
);
439 /* During incremental linking we need to keep symbol weak for future
440 linking. We can still drop definition if we know non-LTO world prevails. */
441 if (!flag_incremental_link
)
443 DECL_WEAK (node
->decl
) = false;
444 node
->set_comdat_group (NULL
);
445 node
->dissolve_same_comdat_group_list ();
449 DECL_EXTERNAL (node
->decl
) = true;
450 node
->set_comdat_group (NULL
);
451 node
->dissolve_same_comdat_group_list ();
455 /* Decide on visibility of all symbols. */
458 function_and_variable_visibility (bool whole_program
)
460 struct cgraph_node
*node
;
463 /* All aliases should be procssed at this point. */
464 gcc_checking_assert (!alias_pairs
|| !alias_pairs
->length ());
466 FOR_EACH_FUNCTION (node
)
468 int flags
= flags_from_decl_or_type (node
->decl
);
470 /* Optimize away PURE and CONST constructors and destructors. */
472 && (flags
& (ECF_CONST
| ECF_PURE
))
473 && !(flags
& ECF_LOOPING_CONST_OR_PURE
))
475 DECL_STATIC_CONSTRUCTOR (node
->decl
) = 0;
476 DECL_STATIC_DESTRUCTOR (node
->decl
) = 0;
479 /* Frontends and alias code marks nodes as needed before parsing is finished.
480 We may end up marking as node external nodes where this flag is meaningless
482 if (DECL_EXTERNAL (node
->decl
) || !node
->definition
)
484 node
->force_output
= 0;
485 node
->forced_by_abi
= 0;
488 /* C++ FE on lack of COMDAT support create local COMDAT functions
489 (that ought to be shared but can not due to object format
490 limitations). It is necessary to keep the flag to make rest of C++ FE
491 happy. Clear the flag here to avoid confusion in middle-end. */
492 if (DECL_COMDAT (node
->decl
) && !TREE_PUBLIC (node
->decl
))
493 DECL_COMDAT (node
->decl
) = 0;
495 /* For external decls stop tracking same_comdat_group. It doesn't matter
496 what comdat group they are in when they won't be emitted in this TU. */
497 if (node
->same_comdat_group
&& DECL_EXTERNAL (node
->decl
))
501 for (symtab_node
*n
= node
->same_comdat_group
;
503 n
= n
->same_comdat_group
)
504 /* If at least one of same comdat group functions is external,
505 all of them have to be, otherwise it is a front-end bug. */
506 gcc_assert (DECL_EXTERNAL (n
->decl
));
508 node
->dissolve_same_comdat_group_list ();
510 gcc_assert ((!DECL_WEAK (node
->decl
)
511 && !DECL_COMDAT (node
->decl
))
512 || TREE_PUBLIC (node
->decl
)
514 || DECL_EXTERNAL (node
->decl
));
515 if (cgraph_externally_visible_p (node
, whole_program
))
517 gcc_assert (!node
->global
.inlined_to
);
518 node
->externally_visible
= true;
522 node
->externally_visible
= false;
523 node
->forced_by_abi
= false;
525 if (!node
->externally_visible
526 && node
->definition
&& !node
->weakref
527 && !DECL_EXTERNAL (node
->decl
))
529 gcc_assert (whole_program
|| in_lto_p
530 || !TREE_PUBLIC (node
->decl
));
531 node
->unique_name
|= ((node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
532 || node
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
533 && TREE_PUBLIC (node
->decl
)
534 && !flag_incremental_link
);
535 node
->resolution
= LDPR_PREVAILING_DEF_IRONLY
;
536 if (node
->same_comdat_group
&& TREE_PUBLIC (node
->decl
))
538 symtab_node
*next
= node
;
540 /* Set all members of comdat group local. */
541 if (node
->same_comdat_group
)
542 for (next
= node
->same_comdat_group
;
544 next
= next
->same_comdat_group
)
546 next
->set_comdat_group (NULL
);
548 next
->set_section (NULL
);
549 if (!next
->transparent_alias
)
550 next
->make_decl_local ();
551 next
->unique_name
|= ((next
->resolution
== LDPR_PREVAILING_DEF_IRONLY
552 || next
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
553 && TREE_PUBLIC (next
->decl
)
554 && !flag_incremental_link
);
556 /* cgraph_externally_visible_p has already checked all other nodes
557 in the group and they will all be made local. We need to
558 dissolve the group at once so that the predicate does not
560 node
->dissolve_same_comdat_group_list ();
562 if (TREE_PUBLIC (node
->decl
))
563 node
->set_comdat_group (NULL
);
564 if (DECL_COMDAT (node
->decl
) && !node
->alias
)
565 node
->set_section (NULL
);
566 if (!node
->transparent_alias
)
567 node
->make_decl_local ();
570 if (node
->thunk
.thunk_p
571 && !node
->thunk
.add_pointer_bounds_args
572 && TREE_PUBLIC (node
->decl
))
574 struct cgraph_node
*decl_node
= node
;
576 decl_node
= decl_node
->callees
->callee
->function_symbol ();
578 /* Thunks have the same visibility as function they are attached to.
579 Make sure the C++ front end set this up properly. */
580 if (DECL_ONE_ONLY (decl_node
->decl
))
582 gcc_checking_assert (DECL_COMDAT (node
->decl
)
583 == DECL_COMDAT (decl_node
->decl
));
584 gcc_checking_assert (node
->in_same_comdat_group_p (decl_node
));
585 gcc_checking_assert (node
->same_comdat_group
);
587 node
->forced_by_abi
= decl_node
->forced_by_abi
;
588 if (DECL_EXTERNAL (decl_node
->decl
))
589 DECL_EXTERNAL (node
->decl
) = 1;
592 update_visibility_by_resolution_info (node
);
594 FOR_EACH_DEFINED_FUNCTION (node
)
596 if (!node
->local
.local
)
597 node
->local
.local
|= node
->local_p ();
599 /* If we know that function can not be overwritten by a
600 different semantics and moreover its section can not be
601 discarded, replace all direct calls by calls to an
602 noninterposable alias. This make dynamic linking cheaper and
603 enable more optimization.
605 TODO: We can also update virtual tables. */
607 && can_replace_by_local_alias (node
))
609 cgraph_node
*alias
= dyn_cast
<cgraph_node
*>
610 (node
->noninterposable_alias ());
612 if (alias
&& alias
!= node
)
614 while (node
->callers
)
616 struct cgraph_edge
*e
= node
->callers
;
618 e
->redirect_callee (alias
);
619 if (gimple_has_body_p (e
->caller
->decl
))
621 push_cfun (DECL_STRUCT_FUNCTION (e
->caller
->decl
));
622 e
->redirect_call_stmt_to_callee ();
629 FOR_EACH_VARIABLE (vnode
)
631 /* weak flag makes no sense on local variables. */
632 gcc_assert (!DECL_WEAK (vnode
->decl
)
634 || TREE_PUBLIC (vnode
->decl
)
635 || DECL_EXTERNAL (vnode
->decl
));
636 /* In several cases declarations can not be common:
638 - when declaration has initializer
640 - when it has specific section
641 - when it resides in non-generic address space.
642 - if declaration is local, it will get into .local common section
643 so common flag is not needed. Frontends still produce these in
644 certain cases, such as for:
646 static int a __attribute__ ((common))
648 Canonicalize things here and clear the redundant flag. */
649 if (DECL_COMMON (vnode
->decl
)
650 && (!(TREE_PUBLIC (vnode
->decl
)
651 || DECL_EXTERNAL (vnode
->decl
))
652 || (DECL_INITIAL (vnode
->decl
)
653 && DECL_INITIAL (vnode
->decl
) != error_mark_node
)
654 || DECL_WEAK (vnode
->decl
)
655 || DECL_SECTION_NAME (vnode
->decl
) != NULL
656 || ! (ADDR_SPACE_GENERIC_P
657 (TYPE_ADDR_SPACE (TREE_TYPE (vnode
->decl
))))))
658 DECL_COMMON (vnode
->decl
) = 0;
660 FOR_EACH_DEFINED_VARIABLE (vnode
)
662 if (!vnode
->definition
)
664 if (vnode
->externally_visible_p ())
665 vnode
->externally_visible
= true;
668 vnode
->externally_visible
= false;
669 vnode
->forced_by_abi
= false;
671 if (lookup_attribute ("no_reorder",
672 DECL_ATTRIBUTES (vnode
->decl
)))
673 vnode
->no_reorder
= 1;
674 if (!vnode
->externally_visible
675 && !vnode
->transparent_alias
)
677 gcc_assert (in_lto_p
|| whole_program
|| !TREE_PUBLIC (vnode
->decl
));
678 vnode
->unique_name
|= ((vnode
->resolution
== LDPR_PREVAILING_DEF_IRONLY
680 == LDPR_PREVAILING_DEF_IRONLY_EXP
)
681 && TREE_PUBLIC (vnode
->decl
)
682 && !flag_incremental_link
);
683 if (vnode
->same_comdat_group
&& TREE_PUBLIC (vnode
->decl
))
685 symtab_node
*next
= vnode
;
687 /* Set all members of comdat group local. */
688 if (vnode
->same_comdat_group
)
689 for (next
= vnode
->same_comdat_group
;
691 next
= next
->same_comdat_group
)
693 next
->set_comdat_group (NULL
);
695 next
->set_section (NULL
);
696 if (!next
->transparent_alias
)
698 next
->make_decl_local ();
699 next
->unique_name
|= ((next
->resolution
== LDPR_PREVAILING_DEF_IRONLY
700 || next
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
701 && TREE_PUBLIC (next
->decl
)
702 && !flag_incremental_link
);
705 vnode
->dissolve_same_comdat_group_list ();
707 if (TREE_PUBLIC (vnode
->decl
))
708 vnode
->set_comdat_group (NULL
);
709 if (DECL_COMDAT (vnode
->decl
) && !vnode
->alias
)
710 vnode
->set_section (NULL
);
711 if (!vnode
->transparent_alias
)
713 vnode
->make_decl_local ();
714 vnode
->resolution
= LDPR_PREVAILING_DEF_IRONLY
;
717 update_visibility_by_resolution_info (vnode
);
719 /* Update virtual tables to point to local aliases where possible. */
720 if (DECL_VIRTUAL_P (vnode
->decl
)
721 && !DECL_EXTERNAL (vnode
->decl
))
727 /* See if there is something to update. */
728 for (i
= 0; vnode
->iterate_reference (i
, ref
); i
++)
729 if (ref
->use
== IPA_REF_ADDR
730 && can_replace_by_local_alias_in_vtable (ref
->referred
))
737 hash_set
<tree
> visited_nodes
;
739 vnode
->get_constructor ();
740 walk_tree (&DECL_INITIAL (vnode
->decl
),
741 update_vtable_references
, NULL
, &visited_nodes
);
742 vnode
->remove_all_references ();
743 record_references_in_initializer (vnode
->decl
, false);
750 fprintf (dump_file
, "\nMarking local functions:");
751 FOR_EACH_DEFINED_FUNCTION (node
)
752 if (node
->local
.local
)
753 fprintf (dump_file
, " %s", node
->name ());
754 fprintf (dump_file
, "\n\n");
755 fprintf (dump_file
, "\nMarking externally visible functions:");
756 FOR_EACH_DEFINED_FUNCTION (node
)
757 if (node
->externally_visible
)
758 fprintf (dump_file
, " %s", node
->name ());
759 fprintf (dump_file
, "\n\n");
760 fprintf (dump_file
, "\nMarking externally visible variables:");
761 FOR_EACH_DEFINED_VARIABLE (vnode
)
762 if (vnode
->externally_visible
)
763 fprintf (dump_file
, " %s", vnode
->name ());
764 fprintf (dump_file
, "\n\n");
766 symtab
->function_flags_ready
= true;
770 /* Local function pass handling visibilities. This happens before LTO streaming
771 so in particular -fwhole-program should be ignored at this level. */
775 const pass_data pass_data_ipa_function_and_variable_visibility
=
777 SIMPLE_IPA_PASS
, /* type */
778 "visibility", /* name */
779 OPTGROUP_NONE
, /* optinfo_flags */
780 TV_CGRAPHOPT
, /* tv_id */
781 0, /* properties_required */
782 0, /* properties_provided */
783 0, /* properties_destroyed */
784 0, /* todo_flags_start */
785 ( TODO_remove_functions
| TODO_dump_symtab
), /* todo_flags_finish */
788 /* Bring functions local at LTO time with -fwhole-program. */
791 whole_program_function_and_variable_visibility (void)
793 function_and_variable_visibility (flag_whole_program
);
795 ipa_discover_readonly_nonaddressable_vars ();
803 const pass_data pass_data_ipa_whole_program_visibility
=
806 "whole-program", /* name */
807 OPTGROUP_NONE
, /* optinfo_flags */
808 TV_CGRAPHOPT
, /* tv_id */
809 0, /* properties_required */
810 0, /* properties_provided */
811 0, /* properties_destroyed */
812 0, /* todo_flags_start */
813 ( TODO_remove_functions
| TODO_dump_symtab
), /* todo_flags_finish */
816 class pass_ipa_whole_program_visibility
: public ipa_opt_pass_d
819 pass_ipa_whole_program_visibility (gcc::context
*ctxt
)
820 : ipa_opt_pass_d (pass_data_ipa_whole_program_visibility
, ctxt
,
821 NULL
, /* generate_summary */
822 NULL
, /* write_summary */
823 NULL
, /* read_summary */
824 NULL
, /* write_optimization_summary */
825 NULL
, /* read_optimization_summary */
826 NULL
, /* stmt_fixup */
827 0, /* function_transform_todo_flags_start */
828 NULL
, /* function_transform */
829 NULL
) /* variable_transform */
832 /* opt_pass methods: */
834 virtual bool gate (function
*)
836 /* Do not re-run on ltrans stage. */
839 virtual unsigned int execute (function
*)
841 return whole_program_function_and_variable_visibility ();
844 }; // class pass_ipa_whole_program_visibility
849 make_pass_ipa_whole_program_visibility (gcc::context
*ctxt
)
851 return new pass_ipa_whole_program_visibility (ctxt
);
854 class pass_ipa_function_and_variable_visibility
: public simple_ipa_opt_pass
857 pass_ipa_function_and_variable_visibility (gcc::context
*ctxt
)
858 : simple_ipa_opt_pass (pass_data_ipa_function_and_variable_visibility
,
862 /* opt_pass methods: */
863 virtual unsigned int execute (function
*)
865 return function_and_variable_visibility (flag_whole_program
&& !flag_lto
);
868 }; // class pass_ipa_function_and_variable_visibility
870 simple_ipa_opt_pass
*
871 make_pass_ipa_function_and_variable_visibility (gcc::context
*ctxt
)
873 return new pass_ipa_function_and_variable_visibility (ctxt
);