2 Copyright (C) 2003-2014 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 "tree-pass.h"
83 #include "gimple-expr.h"
86 /* Return true when NODE can not be local. Worker for cgraph_local_node_p. */
89 cgraph_node::non_local_p (struct cgraph_node
*node
, void *data ATTRIBUTE_UNUSED
)
91 /* FIXME: Aliases can be local, but i386 gets thunks wrong then. */
92 return !(node
->only_called_directly_or_aliased_p ()
93 && !node
->has_aliases_p ()
95 && !DECL_EXTERNAL (node
->decl
)
96 && !node
->externally_visible
97 && !node
->used_from_other_partition
98 && !node
->in_other_partition
);
101 /* Return true when function can be marked local. */
104 cgraph_node::local_p (void)
106 cgraph_node
*n
= ultimate_alias_target ();
108 /* FIXME: thunks can be considered local, but we need prevent i386
109 from attempting to change calling convention of them. */
110 if (n
->thunk
.thunk_p
)
112 return !n
->call_for_symbol_thunks_and_aliases (cgraph_node::non_local_p
,
117 /* Return true when there is a reference to node and it is not vtable. */
120 symtab_node::address_taken_from_non_vtable_p (void)
123 struct ipa_ref
*ref
= NULL
;
125 for (i
= 0; iterate_referring (i
, ref
); i
++)
126 if (ref
->use
== IPA_REF_ADDR
)
129 if (is_a
<cgraph_node
*> (ref
->referring
))
131 node
= dyn_cast
<varpool_node
*> (ref
->referring
);
132 if (!DECL_VIRTUAL_P (node
->decl
))
138 /* A helper for comdat_can_be_unshared_p. */
141 comdat_can_be_unshared_p_1 (symtab_node
*node
)
143 if (!node
->externally_visible
)
145 /* When address is taken, we don't know if equality comparison won't
146 break eventually. Exception are virutal functions, C++
147 constructors/destructors and vtables, where this is not possible by
148 language standard. */
149 if (!DECL_VIRTUAL_P (node
->decl
)
150 && (TREE_CODE (node
->decl
) != FUNCTION_DECL
151 || (!DECL_CXX_CONSTRUCTOR_P (node
->decl
)
152 && !DECL_CXX_DESTRUCTOR_P (node
->decl
)))
153 && node
->address_taken_from_non_vtable_p ())
156 /* If the symbol is used in some weird way, better to not touch it. */
157 if (node
->force_output
)
160 /* Explicit instantiations needs to be output when possibly
162 if (node
->forced_by_abi
163 && TREE_PUBLIC (node
->decl
)
164 && (node
->resolution
!= LDPR_PREVAILING_DEF_IRONLY
165 && !flag_whole_program
))
168 /* Non-readonly and volatile variables can not be duplicated. */
169 if (is_a
<varpool_node
*> (node
)
170 && (!TREE_READONLY (node
->decl
)
171 || TREE_THIS_VOLATILE (node
->decl
)))
176 /* COMDAT functions must be shared only if they have address taken,
177 otherwise we can produce our own private implementation with
179 Return true when turning COMDAT functoin static can not lead to wrong
180 code when the resulting object links with a library defining same COMDAT.
182 Virtual functions do have their addresses taken from the vtables,
183 but in C++ there is no way to compare their addresses for equality. */
186 comdat_can_be_unshared_p (symtab_node
*node
)
188 if (!comdat_can_be_unshared_p_1 (node
))
190 if (node
->same_comdat_group
)
194 /* If more than one function is in the same COMDAT group, it must
195 be shared even if just one function in the comdat group has
197 for (next
= node
->same_comdat_group
;
198 next
!= node
; next
= next
->same_comdat_group
)
199 if (!comdat_can_be_unshared_p_1 (next
))
205 /* Return true when function NODE should be considered externally visible. */
208 cgraph_externally_visible_p (struct cgraph_node
*node
,
211 if (!node
->definition
)
213 if (!TREE_PUBLIC (node
->decl
)
214 || DECL_EXTERNAL (node
->decl
))
217 /* Do not try to localize built-in functions yet. One of problems is that we
218 end up mangling their asm for WHOPR that makes it impossible to call them
219 using the implicit built-in declarations anymore. Similarly this enables
220 us to remove them as unreachable before actual calls may appear during
221 expansion or folding. */
222 if (DECL_BUILT_IN (node
->decl
))
225 /* If linker counts on us, we must preserve the function. */
226 if (node
->used_from_object_file_p ())
228 if (DECL_PRESERVE_P (node
->decl
))
230 if (lookup_attribute ("externally_visible",
231 DECL_ATTRIBUTES (node
->decl
)))
233 if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
234 && lookup_attribute ("dllexport",
235 DECL_ATTRIBUTES (node
->decl
)))
237 if (node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
)
239 /* When doing LTO or whole program, we can bring COMDAT functoins static.
240 This improves code quality and we know we will duplicate them at most twice
241 (in the case that we are not using plugin and link with object file
242 implementing same COMDAT) */
243 if ((in_lto_p
|| whole_program
)
244 && DECL_COMDAT (node
->decl
)
245 && comdat_can_be_unshared_p (node
))
248 /* When doing link time optimizations, hidden symbols become local. */
250 && (DECL_VISIBILITY (node
->decl
) == VISIBILITY_HIDDEN
251 || DECL_VISIBILITY (node
->decl
) == VISIBILITY_INTERNAL
)
252 /* Be sure that node is defined in IR file, not in other object
253 file. In that case we don't set used_from_other_object_file. */
256 else if (!whole_program
)
259 if (MAIN_NAME_P (DECL_NAME (node
->decl
)))
265 /* Return true when variable should be considered externally visible. */
268 varpool_node::externally_visible_p (void)
270 if (DECL_EXTERNAL (decl
))
273 if (!TREE_PUBLIC (decl
))
276 /* If linker counts on us, we must preserve the function. */
277 if (used_from_object_file_p ())
280 if (DECL_HARD_REGISTER (decl
))
282 if (DECL_PRESERVE_P (decl
))
284 if (lookup_attribute ("externally_visible",
285 DECL_ATTRIBUTES (decl
)))
287 if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
288 && lookup_attribute ("dllexport",
289 DECL_ATTRIBUTES (decl
)))
292 /* See if we have linker information about symbol not being used or
293 if we need to make guess based on the declaration.
295 Even if the linker clams the symbol is unused, never bring internal
296 symbols that are declared by user as used or externally visible.
297 This is needed for i.e. references from asm statements. */
298 if (used_from_object_file_p ())
300 if (resolution
== LDPR_PREVAILING_DEF_IRONLY
)
303 /* As a special case, the COMDAT virtual tables can be unshared.
304 In LTO mode turn vtables into static variables. The variable is readonly,
305 so this does not enable more optimization, but referring static var
306 is faster for dynamic linking. Also this match logic hidding vtables
307 from LTO symbol tables. */
308 if ((in_lto_p
|| flag_whole_program
)
309 && DECL_COMDAT (decl
)
310 && comdat_can_be_unshared_p (this))
313 /* When doing link time optimizations, hidden symbols become local. */
315 && (DECL_VISIBILITY (decl
) == VISIBILITY_HIDDEN
316 || DECL_VISIBILITY (decl
) == VISIBILITY_INTERNAL
)
317 /* Be sure that node is defined in IR file, not in other object
318 file. In that case we don't set used_from_other_object_file. */
321 else if (!flag_whole_program
)
324 /* Do not attempt to privatize COMDATS by default.
325 This would break linking with C++ libraries sharing
328 FIXME: We can do so for readonly vars with no address taken and
329 possibly also for vtables since no direct pointer comparsion is done.
330 It might be interesting to do so to reduce linking overhead. */
331 if (DECL_COMDAT (decl
) || DECL_WEAK (decl
))
336 /* Return true if reference to NODE can be replaced by a local alias.
337 Local aliases save dynamic linking overhead and enable more optimizations.
341 can_replace_by_local_alias (symtab_node
*node
)
343 return (node
->get_availability () > AVAIL_INTERPOSABLE
344 && !decl_binds_to_current_def_p (node
->decl
)
345 && !node
->can_be_discarded_p ());
348 /* Return true if we can replace refernece to NODE by local alias
349 within a virtual table. Generally we can replace function pointers
350 and virtual table pointers. */
353 can_replace_by_local_alias_in_vtable (symtab_node
*node
)
355 if (is_a
<varpool_node
*> (node
)
356 && !DECL_VIRTUAL_P (node
->decl
))
358 return can_replace_by_local_alias (node
);
361 /* walk_tree callback that rewrites initializer references. */
364 update_vtable_references (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
366 if (TREE_CODE (*tp
) == VAR_DECL
367 || TREE_CODE (*tp
) == FUNCTION_DECL
)
369 if (can_replace_by_local_alias_in_vtable (symtab_node::get (*tp
)))
370 *tp
= symtab_node::get (*tp
)->noninterposable_alias ()->decl
;
373 else if (IS_TYPE_OR_DECL_P (*tp
))
378 /* In LTO we can remove COMDAT groups and weak symbols.
379 Either turn them into normal symbols or external symbol depending on
383 update_visibility_by_resolution_info (symtab_node
* node
)
387 if (!node
->externally_visible
388 || (!DECL_WEAK (node
->decl
) && !DECL_ONE_ONLY (node
->decl
))
389 || node
->resolution
== LDPR_UNKNOWN
)
392 define
= (node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
393 || node
->resolution
== LDPR_PREVAILING_DEF
394 || node
->resolution
== LDPR_UNDEF
395 || node
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
);
397 /* The linker decisions ought to agree in the whole group. */
398 if (node
->same_comdat_group
)
399 for (symtab_node
*next
= node
->same_comdat_group
;
400 next
!= node
; next
= next
->same_comdat_group
)
401 gcc_assert (!next
->externally_visible
402 || define
== (next
->resolution
== LDPR_PREVAILING_DEF_IRONLY
403 || next
->resolution
== LDPR_PREVAILING_DEF
404 || next
->resolution
== LDPR_UNDEF
405 || next
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
));
407 if (node
->same_comdat_group
)
408 for (symtab_node
*next
= node
->same_comdat_group
;
409 next
!= node
; next
= next
->same_comdat_group
)
411 next
->set_comdat_group (NULL
);
412 DECL_WEAK (next
->decl
) = false;
413 if (next
->externally_visible
415 DECL_EXTERNAL (next
->decl
) = true;
417 node
->set_comdat_group (NULL
);
418 DECL_WEAK (node
->decl
) = false;
420 DECL_EXTERNAL (node
->decl
) = true;
421 node
->dissolve_same_comdat_group_list ();
424 /* Decide on visibility of all symbols. */
427 function_and_variable_visibility (bool whole_program
)
429 struct cgraph_node
*node
;
432 /* All aliases should be procssed at this point. */
433 gcc_checking_assert (!alias_pairs
|| !alias_pairs
->length ());
435 FOR_EACH_FUNCTION (node
)
437 int flags
= flags_from_decl_or_type (node
->decl
);
439 /* Optimize away PURE and CONST constructors and destructors. */
441 && (flags
& (ECF_CONST
| ECF_PURE
))
442 && !(flags
& ECF_LOOPING_CONST_OR_PURE
))
444 DECL_STATIC_CONSTRUCTOR (node
->decl
) = 0;
445 DECL_STATIC_DESTRUCTOR (node
->decl
) = 0;
448 /* Frontends and alias code marks nodes as needed before parsing is finished.
449 We may end up marking as node external nodes where this flag is meaningless
451 if (DECL_EXTERNAL (node
->decl
) || !node
->definition
)
453 node
->force_output
= 0;
454 node
->forced_by_abi
= 0;
457 /* C++ FE on lack of COMDAT support create local COMDAT functions
458 (that ought to be shared but can not due to object format
459 limitations). It is necessary to keep the flag to make rest of C++ FE
460 happy. Clear the flag here to avoid confusion in middle-end. */
461 if (DECL_COMDAT (node
->decl
) && !TREE_PUBLIC (node
->decl
))
462 DECL_COMDAT (node
->decl
) = 0;
464 /* For external decls stop tracking same_comdat_group. It doesn't matter
465 what comdat group they are in when they won't be emitted in this TU. */
466 if (node
->same_comdat_group
&& DECL_EXTERNAL (node
->decl
))
468 #ifdef ENABLE_CHECKING
471 for (n
= node
->same_comdat_group
;
473 n
= n
->same_comdat_group
)
474 /* If at least one of same comdat group functions is external,
475 all of them have to be, otherwise it is a front-end bug. */
476 gcc_assert (DECL_EXTERNAL (n
->decl
));
478 node
->dissolve_same_comdat_group_list ();
480 gcc_assert ((!DECL_WEAK (node
->decl
)
481 && !DECL_COMDAT (node
->decl
))
482 || TREE_PUBLIC (node
->decl
)
484 || DECL_EXTERNAL (node
->decl
));
485 if (cgraph_externally_visible_p (node
, whole_program
))
487 gcc_assert (!node
->global
.inlined_to
);
488 node
->externally_visible
= true;
492 node
->externally_visible
= false;
493 node
->forced_by_abi
= false;
495 if (!node
->externally_visible
496 && node
->definition
&& !node
->weakref
497 && !DECL_EXTERNAL (node
->decl
))
499 gcc_assert (whole_program
|| in_lto_p
500 || !TREE_PUBLIC (node
->decl
));
501 node
->unique_name
= ((node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
503 || node
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
504 && TREE_PUBLIC (node
->decl
));
505 node
->resolution
= LDPR_PREVAILING_DEF_IRONLY
;
506 if (node
->same_comdat_group
&& TREE_PUBLIC (node
->decl
))
508 symtab_node
*next
= node
;
510 /* Set all members of comdat group local. */
511 if (node
->same_comdat_group
)
512 for (next
= node
->same_comdat_group
;
514 next
= next
->same_comdat_group
)
516 next
->set_comdat_group (NULL
);
518 next
->set_section (NULL
);
519 next
->make_decl_local ();
520 next
->unique_name
= ((next
->resolution
== LDPR_PREVAILING_DEF_IRONLY
522 || next
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
523 && TREE_PUBLIC (next
->decl
));
525 /* cgraph_externally_visible_p has already checked all other nodes
526 in the group and they will all be made local. We need to
527 dissolve the group at once so that the predicate does not
529 node
->dissolve_same_comdat_group_list ();
531 if (TREE_PUBLIC (node
->decl
))
532 node
->set_comdat_group (NULL
);
533 if (DECL_COMDAT (node
->decl
) && !node
->alias
)
534 node
->set_section (NULL
);
535 node
->make_decl_local ();
538 if (node
->thunk
.thunk_p
539 && TREE_PUBLIC (node
->decl
))
541 struct cgraph_node
*decl_node
= node
;
543 decl_node
= decl_node
->callees
->callee
->function_symbol ();
545 /* Thunks have the same visibility as function they are attached to.
546 Make sure the C++ front end set this up properly. */
547 if (DECL_ONE_ONLY (decl_node
->decl
))
549 gcc_checking_assert (DECL_COMDAT (node
->decl
)
550 == DECL_COMDAT (decl_node
->decl
));
551 gcc_checking_assert (node
->in_same_comdat_group_p (decl_node
));
552 gcc_checking_assert (node
->same_comdat_group
);
554 node
->forced_by_abi
= decl_node
->forced_by_abi
;
555 if (DECL_EXTERNAL (decl_node
->decl
))
556 DECL_EXTERNAL (node
->decl
) = 1;
559 update_visibility_by_resolution_info (node
);
561 FOR_EACH_DEFINED_FUNCTION (node
)
563 node
->local
.local
|= node
->local_p ();
565 /* If we know that function can not be overwritten by a different semantics
566 and moreover its section can not be discarded, replace all direct calls
567 by calls to an noninterposable alias. This make dynamic linking
568 cheaper and enable more optimization.
570 TODO: We can also update virtual tables. */
572 && can_replace_by_local_alias (node
))
574 cgraph_node
*alias
= dyn_cast
<cgraph_node
*>
575 (node
->noninterposable_alias ());
577 if (alias
&& alias
!= node
)
579 while (node
->callers
)
581 struct cgraph_edge
*e
= node
->callers
;
583 e
->redirect_callee (alias
);
584 if (gimple_has_body_p (e
->caller
->decl
))
586 push_cfun (DECL_STRUCT_FUNCTION (e
->caller
->decl
));
587 e
->redirect_call_stmt_to_callee ();
594 FOR_EACH_VARIABLE (vnode
)
596 /* weak flag makes no sense on local variables. */
597 gcc_assert (!DECL_WEAK (vnode
->decl
)
599 || TREE_PUBLIC (vnode
->decl
)
600 || DECL_EXTERNAL (vnode
->decl
));
601 /* In several cases declarations can not be common:
603 - when declaration has initializer
605 - when it has specific section
606 - when it resides in non-generic address space.
607 - if declaration is local, it will get into .local common section
608 so common flag is not needed. Frontends still produce these in
609 certain cases, such as for:
611 static int a __attribute__ ((common))
613 Canonicalize things here and clear the redundant flag. */
614 if (DECL_COMMON (vnode
->decl
)
615 && (!(TREE_PUBLIC (vnode
->decl
)
616 || DECL_EXTERNAL (vnode
->decl
))
617 || (DECL_INITIAL (vnode
->decl
)
618 && DECL_INITIAL (vnode
->decl
) != error_mark_node
)
619 || DECL_WEAK (vnode
->decl
)
620 || DECL_SECTION_NAME (vnode
->decl
) != NULL
621 || ! (ADDR_SPACE_GENERIC_P
622 (TYPE_ADDR_SPACE (TREE_TYPE (vnode
->decl
))))))
623 DECL_COMMON (vnode
->decl
) = 0;
625 FOR_EACH_DEFINED_VARIABLE (vnode
)
627 if (!vnode
->definition
)
629 if (vnode
->externally_visible_p ())
630 vnode
->externally_visible
= true;
633 vnode
->externally_visible
= false;
634 vnode
->forced_by_abi
= false;
636 if (!vnode
->externally_visible
639 gcc_assert (in_lto_p
|| whole_program
|| !TREE_PUBLIC (vnode
->decl
));
640 vnode
->unique_name
= ((vnode
->resolution
== LDPR_PREVAILING_DEF_IRONLY
641 || vnode
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
642 && TREE_PUBLIC (vnode
->decl
));
643 if (vnode
->same_comdat_group
&& TREE_PUBLIC (vnode
->decl
))
645 symtab_node
*next
= vnode
;
647 /* Set all members of comdat group local. */
648 if (vnode
->same_comdat_group
)
649 for (next
= vnode
->same_comdat_group
;
651 next
= next
->same_comdat_group
)
653 next
->set_comdat_group (NULL
);
655 next
->set_section (NULL
);
656 next
->make_decl_local ();
657 next
->unique_name
= ((next
->resolution
== LDPR_PREVAILING_DEF_IRONLY
659 || next
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
660 && TREE_PUBLIC (next
->decl
));
662 vnode
->dissolve_same_comdat_group_list ();
664 if (TREE_PUBLIC (vnode
->decl
))
665 vnode
->set_comdat_group (NULL
);
666 if (DECL_COMDAT (vnode
->decl
) && !vnode
->alias
)
667 vnode
->set_section (NULL
);
668 vnode
->make_decl_local ();
669 vnode
->resolution
= LDPR_PREVAILING_DEF_IRONLY
;
671 update_visibility_by_resolution_info (vnode
);
673 /* Update virtual tables to point to local aliases where possible. */
674 if (DECL_VIRTUAL_P (vnode
->decl
)
675 && !DECL_EXTERNAL (vnode
->decl
))
681 /* See if there is something to update. */
682 for (i
= 0; vnode
->iterate_referring (i
, ref
); i
++)
683 if (ref
->use
== IPA_REF_ADDR
684 && can_replace_by_local_alias_in_vtable (ref
->referred
))
691 hash_set
<tree
> visited_nodes
;
693 vnode
->get_constructor ();
694 walk_tree (&DECL_INITIAL (vnode
->decl
),
695 update_vtable_references
, NULL
, &visited_nodes
);
696 vnode
->remove_all_references ();
697 record_references_in_initializer (vnode
->decl
, false);
704 fprintf (dump_file
, "\nMarking local functions:");
705 FOR_EACH_DEFINED_FUNCTION (node
)
706 if (node
->local
.local
)
707 fprintf (dump_file
, " %s", node
->name ());
708 fprintf (dump_file
, "\n\n");
709 fprintf (dump_file
, "\nMarking externally visible functions:");
710 FOR_EACH_DEFINED_FUNCTION (node
)
711 if (node
->externally_visible
)
712 fprintf (dump_file
, " %s", node
->name ());
713 fprintf (dump_file
, "\n\n");
714 fprintf (dump_file
, "\nMarking externally visible variables:");
715 FOR_EACH_DEFINED_VARIABLE (vnode
)
716 if (vnode
->externally_visible
)
717 fprintf (dump_file
, " %s", vnode
->name ());
718 fprintf (dump_file
, "\n\n");
720 symtab
->function_flags_ready
= true;
724 /* Local function pass handling visibilities. This happens before LTO streaming
725 so in particular -fwhole-program should be ignored at this level. */
729 const pass_data pass_data_ipa_function_and_variable_visibility
=
731 SIMPLE_IPA_PASS
, /* type */
732 "visibility", /* name */
733 OPTGROUP_NONE
, /* optinfo_flags */
734 TV_CGRAPHOPT
, /* tv_id */
735 0, /* properties_required */
736 0, /* properties_provided */
737 0, /* properties_destroyed */
738 0, /* todo_flags_start */
739 ( TODO_remove_functions
| TODO_dump_symtab
), /* todo_flags_finish */
742 /* Bring functions local at LTO time with -fwhole-program. */
745 whole_program_function_and_variable_visibility (void)
747 function_and_variable_visibility (flag_whole_program
);
749 ipa_discover_readonly_nonaddressable_vars ();
757 const pass_data pass_data_ipa_whole_program_visibility
=
760 "whole-program", /* name */
761 OPTGROUP_NONE
, /* optinfo_flags */
762 TV_CGRAPHOPT
, /* tv_id */
763 0, /* properties_required */
764 0, /* properties_provided */
765 0, /* properties_destroyed */
766 0, /* todo_flags_start */
767 ( TODO_remove_functions
| TODO_dump_symtab
), /* todo_flags_finish */
770 class pass_ipa_whole_program_visibility
: public ipa_opt_pass_d
773 pass_ipa_whole_program_visibility (gcc::context
*ctxt
)
774 : ipa_opt_pass_d (pass_data_ipa_whole_program_visibility
, ctxt
,
775 NULL
, /* generate_summary */
776 NULL
, /* write_summary */
777 NULL
, /* read_summary */
778 NULL
, /* write_optimization_summary */
779 NULL
, /* read_optimization_summary */
780 NULL
, /* stmt_fixup */
781 0, /* function_transform_todo_flags_start */
782 NULL
, /* function_transform */
783 NULL
) /* variable_transform */
786 /* opt_pass methods: */
788 virtual bool gate (function
*)
790 /* Do not re-run on ltrans stage. */
793 virtual unsigned int execute (function
*)
795 return whole_program_function_and_variable_visibility ();
798 }; // class pass_ipa_whole_program_visibility
803 make_pass_ipa_whole_program_visibility (gcc::context
*ctxt
)
805 return new pass_ipa_whole_program_visibility (ctxt
);
808 class pass_ipa_function_and_variable_visibility
: public simple_ipa_opt_pass
811 pass_ipa_function_and_variable_visibility (gcc::context
*ctxt
)
812 : simple_ipa_opt_pass (pass_data_ipa_function_and_variable_visibility
,
816 /* opt_pass methods: */
817 virtual unsigned int execute (function
*)
819 return function_and_variable_visibility (flag_whole_program
&& !flag_lto
);
822 }; // class pass_ipa_function_and_variable_visibility
824 simple_ipa_opt_pass
*
825 make_pass_ipa_function_and_variable_visibility (gcc::context
*ctxt
)
827 return new pass_ipa_function_and_variable_visibility (ctxt
);