1 /* Basic IPA optimizations and utilities.
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/>. */
22 #include "coretypes.h"
26 #include "stringpool.h"
28 #include "tree-pass.h"
29 #include "pointer-set.h"
30 #include "gimple-expr.h"
34 #include "tree-iterator.h"
35 #include "ipa-utils.h"
36 #include "ipa-inline.h"
37 #include "tree-inline.h"
41 /* Return true when NODE can not be local. Worker for cgraph_local_node_p. */
44 cgraph_non_local_node_p_1 (struct cgraph_node
*node
, void *data ATTRIBUTE_UNUSED
)
46 /* FIXME: Aliases can be local, but i386 gets thunks wrong then. */
47 return !(cgraph_only_called_directly_or_aliased_p (node
)
48 && !ipa_ref_has_aliases_p (&node
->ref_list
)
50 && !DECL_EXTERNAL (node
->decl
)
51 && !node
->externally_visible
52 && !node
->used_from_other_partition
53 && !node
->in_other_partition
);
56 /* Return true when function can be marked local. */
59 cgraph_local_node_p (struct cgraph_node
*node
)
61 struct cgraph_node
*n
= cgraph_function_or_thunk_node (node
, NULL
);
63 /* FIXME: thunks can be considered local, but we need prevent i386
64 from attempting to change calling convention of them. */
67 return !cgraph_for_node_and_aliases (n
,
68 cgraph_non_local_node_p_1
, NULL
, true);
72 /* Return true when NODE has ADDR reference. */
75 has_addr_references_p (struct cgraph_node
*node
,
76 void *data ATTRIBUTE_UNUSED
)
81 for (i
= 0; ipa_ref_list_referring_iterate (&node
->ref_list
,
83 if (ref
->use
== IPA_REF_ADDR
)
88 /* Look for all functions inlined to NODE and update their inlined_to pointers
92 update_inlined_to_pointer (struct cgraph_node
*node
, struct cgraph_node
*inlined_to
)
94 struct cgraph_edge
*e
;
95 for (e
= node
->callees
; e
; e
= e
->next_callee
)
96 if (e
->callee
->global
.inlined_to
)
98 e
->callee
->global
.inlined_to
= inlined_to
;
99 update_inlined_to_pointer (e
->callee
, inlined_to
);
103 /* Add symtab NODE to queue starting at FIRST.
105 The queue is linked via AUX pointers and terminated by pointer to 1.
106 We enqueue nodes at two occasions: when we find them reachable or when we find
107 their bodies needed for further clonning. In the second case we mark them
108 by pointer to 2 after processing so they are re-queue when they become
112 enqueue_node (symtab_node
*node
, symtab_node
**first
,
113 struct pointer_set_t
*reachable
)
115 /* Node is still in queue; do nothing. */
116 if (node
->aux
&& node
->aux
!= (void *) 2)
118 /* Node was already processed as unreachable, re-enqueue
119 only if it became reachable now. */
120 if (node
->aux
== (void *)2 && !pointer_set_contains (reachable
, node
))
126 /* Process references. */
129 process_references (struct ipa_ref_list
*list
,
131 bool before_inlining_p
,
132 struct pointer_set_t
*reachable
)
136 for (i
= 0; ipa_ref_list_reference_iterate (list
, i
, ref
); i
++)
138 symtab_node
*node
= ref
->referred
;
140 if (node
->definition
&& !node
->in_other_partition
141 && ((!DECL_EXTERNAL (node
->decl
) || node
->alias
)
142 || (((before_inlining_p
143 && (cgraph_state
< CGRAPH_STATE_IPA_SSA
144 || !lookup_attribute ("always_inline",
145 DECL_ATTRIBUTES (node
->decl
)))))
146 /* We use variable constructors during late complation for
147 constant folding. Keep references alive so partitioning
148 knows about potential references. */
149 || (TREE_CODE (node
->decl
) == VAR_DECL
151 && ctor_for_folding (node
->decl
)
152 != error_mark_node
))))
153 pointer_set_insert (reachable
, node
);
154 enqueue_node (node
, first
, reachable
);
158 /* EDGE is an polymorphic call. If BEFORE_INLINING_P is set, mark
159 all its potential targets as reachable to permit later inlining if
160 devirtualization happens. After inlining still keep their declarations
161 around, so we can devirtualize to a direct call.
163 Also try to make trivial devirutalization when no or only one target is
167 walk_polymorphic_call_targets (pointer_set_t
*reachable_call_targets
,
168 struct cgraph_edge
*edge
,
170 pointer_set_t
*reachable
, bool before_inlining_p
)
175 vec
<cgraph_node
*>targets
176 = possible_polymorphic_call_targets
177 (edge
, &final
, &cache_token
);
179 if (!pointer_set_insert (reachable_call_targets
,
182 for (i
= 0; i
< targets
.length (); i
++)
184 struct cgraph_node
*n
= targets
[i
];
186 /* Do not bother to mark virtual methods in anonymous namespace;
187 either we will find use of virtual table defining it, or it is
189 if (TREE_CODE (TREE_TYPE (n
->decl
)) == METHOD_TYPE
190 && type_in_anonymous_namespace_p
191 (method_class_type (TREE_TYPE (n
->decl
))))
194 /* Prior inlining, keep alive bodies of possible targets for
197 && (before_inlining_p
198 && (cgraph_state
< CGRAPH_STATE_IPA_SSA
199 || !lookup_attribute ("always_inline",
200 DECL_ATTRIBUTES (n
->decl
)))))
201 pointer_set_insert (reachable
, n
);
203 /* Even after inlining we want to keep the possible targets in the
204 boundary, so late passes can still produce direct call even if
205 the chance for inlining is lost. */
206 enqueue_node (n
, first
, reachable
);
210 /* Very trivial devirtualization; when the type is
211 final or anonymous (so we know all its derivation)
212 and there is only one possible virtual call target,
213 make the edge direct. */
216 if (targets
.length () <= 1)
218 cgraph_node
*target
, *node
= edge
->caller
;
219 if (targets
.length () == 1)
222 target
= cgraph_get_create_node
223 (builtin_decl_implicit (BUILT_IN_UNREACHABLE
));
227 "Devirtualizing call in %s/%i to %s/%i\n",
228 edge
->caller
->name (),
230 target
->name (), target
->order
);
231 edge
= cgraph_make_edge_direct (edge
, target
);
232 if (inline_summary_vec
)
233 inline_update_overall_summary (node
);
234 else if (edge
->call_stmt
)
235 cgraph_redirect_edge_call_stmt_to_callee (edge
);
240 /* Perform reachability analysis and reclaim all unreachable nodes.
242 The algorithm is basically mark&sweep but with some extra refinements:
244 - reachable extern inline functions needs special handling; the bodies needs
245 to stay in memory until inlining in hope that they will be inlined.
246 After inlining we release their bodies and turn them into unanalyzed
247 nodes even when they are reachable.
249 BEFORE_INLINING_P specify whether we are before or after inlining.
251 - virtual functions are kept in callgraph even if they seem unreachable in
252 hope calls to them will be devirtualized.
254 Again we remove them after inlining. In late optimization some
255 devirtualization may happen, but it is not important since we won't inline
256 the call. In theory early opts and IPA should work out all important cases.
258 - virtual clones needs bodies of their origins for later materialization;
259 this means that we want to keep the body even if the origin is unreachable
260 otherwise. To avoid origin from sitting in the callgraph and being
261 walked by IPA passes, we turn them into unanalyzed nodes with body
264 We maintain set of function declaration where body needs to stay in
265 body_needed_for_clonning
267 Inline clones represent special case: their declaration match the
268 declaration of origin and cgraph_remove_node already knows how to
269 reshape callgraph and preserve body when offline copy of function or
270 inline clone is being removed.
272 - C++ virtual tables keyed to other unit are represented as DECL_EXTERNAL
273 variables with DECL_INITIAL set. We finalize these and keep reachable
274 ones around for constant folding purposes. After inlining we however
275 stop walking their references to let everything static referneced by them
276 to be removed when it is otherwise unreachable.
278 We maintain queue of both reachable symbols (i.e. defined symbols that needs
279 to stay) and symbols that are in boundary (i.e. external symbols referenced
280 by reachable symbols or origins of clones). The queue is represented
281 as linked list by AUX pointer terminated by 1.
283 At the end we keep all reachable symbols. For symbols in boundary we always
284 turn definition into a declaration, but we may keep function body around
285 based on body_needed_for_clonning
287 All symbols that enter the queue have AUX pointer non-zero and are in the
288 boundary. Pointer set REACHABLE is used to track reachable symbols.
290 Every symbol can be visited twice - once as part of boundary and once
291 as real reachable symbol. enqueue_node needs to decide whether the
292 node needs to be re-queued for second processing. For this purpose
293 we set AUX pointer of processed symbols in the boundary to constant 2. */
296 symtab_remove_unreachable_nodes (bool before_inlining_p
, FILE *file
)
298 symtab_node
*first
= (symtab_node
*) (void *) 1;
299 struct cgraph_node
*node
, *next
;
300 varpool_node
*vnode
, *vnext
;
301 bool changed
= false;
302 struct pointer_set_t
*reachable
= pointer_set_create ();
303 struct pointer_set_t
*body_needed_for_clonning
= pointer_set_create ();
304 struct pointer_set_t
*reachable_call_targets
= pointer_set_create ();
306 timevar_push (TV_IPA_UNREACHABLE
);
307 #ifdef ENABLE_CHECKING
310 if (optimize
&& flag_devirtualize
)
311 build_type_inheritance_graph ();
313 fprintf (file
, "\nReclaiming functions:");
314 #ifdef ENABLE_CHECKING
315 FOR_EACH_FUNCTION (node
)
316 gcc_assert (!node
->aux
);
317 FOR_EACH_VARIABLE (vnode
)
318 gcc_assert (!vnode
->aux
);
320 /* Mark functions whose bodies are obviously needed.
321 This is mostly when they can be referenced externally. Inline clones
322 are special since their declarations are shared with master clone and thus
323 cgraph_can_remove_if_no_direct_calls_and_refs_p should not be called on them. */
324 FOR_EACH_FUNCTION (node
)
326 node
->used_as_abstract_origin
= false;
328 && !node
->global
.inlined_to
329 && !node
->in_other_partition
330 && !cgraph_can_remove_if_no_direct_calls_and_refs_p (node
))
332 gcc_assert (!node
->global
.inlined_to
);
333 pointer_set_insert (reachable
, node
);
334 enqueue_node (node
, &first
, reachable
);
337 gcc_assert (!node
->aux
);
340 /* Mark variables that are obviously needed. */
341 FOR_EACH_DEFINED_VARIABLE (vnode
)
342 if (!varpool_can_remove_if_no_refs (vnode
)
343 && !vnode
->in_other_partition
)
345 pointer_set_insert (reachable
, vnode
);
346 enqueue_node (vnode
, &first
, reachable
);
349 /* Perform reachability analysis. */
350 while (first
!= (symtab_node
*) (void *) 1)
352 bool in_boundary_p
= !pointer_set_contains (reachable
, first
);
353 symtab_node
*node
= first
;
355 first
= (symtab_node
*)first
->aux
;
357 /* If we are processing symbol in boundary, mark its AUX pointer for
358 possible later re-processing in enqueue_node. */
360 node
->aux
= (void *)2;
363 if (TREE_CODE (node
->decl
) == FUNCTION_DECL
364 && DECL_ABSTRACT_ORIGIN (node
->decl
))
366 struct cgraph_node
*origin_node
367 = cgraph_get_create_node (DECL_ABSTRACT_ORIGIN (node
->decl
));
368 origin_node
->used_as_abstract_origin
= true;
369 enqueue_node (origin_node
, &first
, reachable
);
371 /* If any symbol in a comdat group is reachable, force
372 all externally visible symbols in the same comdat
373 group to be reachable as well. Comdat-local symbols
374 can be discarded if all uses were inlined. */
375 if (node
->same_comdat_group
)
378 for (next
= node
->same_comdat_group
;
380 next
= next
->same_comdat_group
)
381 if (!symtab_comdat_local_p (next
)
382 && !pointer_set_insert (reachable
, next
))
383 enqueue_node (next
, &first
, reachable
);
385 /* Mark references as reachable. */
386 process_references (&node
->ref_list
, &first
,
387 before_inlining_p
, reachable
);
390 if (cgraph_node
*cnode
= dyn_cast
<cgraph_node
> (node
))
392 /* Mark the callees reachable unless they are direct calls to extern
393 inline functions we decided to not inline. */
396 struct cgraph_edge
*e
;
397 /* Keep alive possible targets for devirtualization. */
398 if (optimize
&& flag_devirtualize
)
400 struct cgraph_edge
*next
;
401 for (e
= cnode
->indirect_calls
; e
; e
= next
)
403 next
= e
->next_callee
;
404 if (e
->indirect_info
->polymorphic
)
405 walk_polymorphic_call_targets (reachable_call_targets
,
406 e
, &first
, reachable
,
410 for (e
= cnode
->callees
; e
; e
= e
->next_callee
)
412 if (e
->callee
->definition
413 && !e
->callee
->in_other_partition
414 && (!e
->inline_failed
415 || !DECL_EXTERNAL (e
->callee
->decl
)
417 || before_inlining_p
))
419 /* Be sure that we will not optimize out alias target
421 if (DECL_EXTERNAL (e
->callee
->decl
)
423 && before_inlining_p
)
425 pointer_set_insert (reachable
,
426 cgraph_function_node (e
->callee
));
428 pointer_set_insert (reachable
, e
->callee
);
430 enqueue_node (e
->callee
, &first
, reachable
);
433 /* When inline clone exists, mark body to be preserved so when removing
434 offline copy of the function we don't kill it. */
435 if (cnode
->global
.inlined_to
)
436 pointer_set_insert (body_needed_for_clonning
, cnode
->decl
);
438 /* For non-inline clones, force their origins to the boundary and ensure
439 that body is not removed. */
440 while (cnode
->clone_of
)
442 bool noninline
= cnode
->clone_of
->decl
!= cnode
->decl
;
443 cnode
= cnode
->clone_of
;
446 pointer_set_insert (body_needed_for_clonning
, cnode
->decl
);
447 enqueue_node (cnode
, &first
, reachable
);
452 /* If any reachable function has simd clones, mark them as
453 reachable as well. */
454 if (cnode
->simd_clones
)
457 for (next
= cnode
->simd_clones
;
459 next
= next
->simdclone
->next_clone
)
461 || !pointer_set_insert (reachable
, next
))
462 enqueue_node (next
, &first
, reachable
);
465 /* When we see constructor of external variable, keep referred nodes in the
466 boundary. This will also hold initializers of the external vars NODE
468 varpool_node
*vnode
= dyn_cast
<varpool_node
> (node
);
470 && DECL_EXTERNAL (node
->decl
)
475 for (int i
= 0; ipa_ref_list_reference_iterate (&node
->ref_list
, i
, ref
); i
++)
476 enqueue_node (ref
->referred
, &first
, reachable
);
480 /* Remove unreachable functions. */
481 for (node
= cgraph_first_function (); node
; node
= next
)
483 next
= cgraph_next_function (node
);
485 /* If node is not needed at all, remove it. */
489 fprintf (file
, " %s/%i", node
->name (), node
->order
);
490 cgraph_remove_node (node
);
493 /* If node is unreachable, remove its body. */
494 else if (!pointer_set_contains (reachable
, node
))
496 if (!pointer_set_contains (body_needed_for_clonning
, node
->decl
))
497 cgraph_release_function_body (node
);
498 else if (!node
->clone_of
)
499 gcc_assert (in_lto_p
|| DECL_RESULT (node
->decl
));
500 if (node
->definition
)
503 fprintf (file
, " %s/%i", node
->name (), node
->order
);
504 node
->body_removed
= true;
505 node
->analyzed
= false;
506 node
->definition
= false;
507 node
->cpp_implicit_alias
= false;
509 node
->thunk
.thunk_p
= false;
510 node
->weakref
= false;
511 /* After early inlining we drop always_inline attributes on
512 bodies of functions that are still referenced (have their
514 DECL_ATTRIBUTES (node
->decl
)
515 = remove_attribute ("always_inline",
516 DECL_ATTRIBUTES (node
->decl
));
517 if (!node
->in_other_partition
)
518 node
->local
.local
= false;
519 cgraph_node_remove_callees (node
);
520 symtab_remove_from_same_comdat_group (node
);
521 ipa_remove_all_references (&node
->ref_list
);
526 gcc_assert (node
->clone_of
|| !cgraph_function_with_gimple_body_p (node
)
527 || in_lto_p
|| DECL_RESULT (node
->decl
));
530 /* Inline clones might be kept around so their materializing allows further
531 cloning. If the function the clone is inlined into is removed, we need
532 to turn it into normal cone. */
533 FOR_EACH_FUNCTION (node
)
535 if (node
->global
.inlined_to
538 gcc_assert (node
->clones
);
539 node
->global
.inlined_to
= NULL
;
540 update_inlined_to_pointer (node
, node
);
545 /* Remove unreachable variables. */
547 fprintf (file
, "\nReclaiming variables:");
548 for (vnode
= varpool_first_variable (); vnode
; vnode
= vnext
)
550 vnext
= varpool_next_variable (vnode
);
552 /* For can_refer_decl_in_current_unit_p we want to track for
553 all external variables if they are defined in other partition
555 && (!flag_ltrans
|| !DECL_EXTERNAL (vnode
->decl
)))
558 fprintf (file
, " %s/%i", vnode
->name (), vnode
->order
);
559 varpool_remove_node (vnode
);
562 else if (!pointer_set_contains (reachable
, vnode
))
565 if (vnode
->definition
)
568 fprintf (file
, " %s", vnode
->name ());
571 vnode
->body_removed
= true;
572 vnode
->definition
= false;
573 vnode
->analyzed
= false;
576 symtab_remove_from_same_comdat_group (vnode
);
578 /* Keep body if it may be useful for constant folding. */
579 if ((init
= ctor_for_folding (vnode
->decl
)) == error_mark_node
)
580 varpool_remove_initializer (vnode
);
582 DECL_INITIAL (vnode
->decl
) = init
;
583 ipa_remove_all_references (&vnode
->ref_list
);
589 pointer_set_destroy (reachable
);
590 pointer_set_destroy (body_needed_for_clonning
);
591 pointer_set_destroy (reachable_call_targets
);
593 /* Now update address_taken flags and try to promote functions to be local. */
595 fprintf (file
, "\nClearing address taken flags:");
596 FOR_EACH_DEFINED_FUNCTION (node
)
597 if (node
->address_taken
598 && !node
->used_from_other_partition
)
600 if (!cgraph_for_node_and_aliases (node
, has_addr_references_p
, NULL
, true))
603 fprintf (file
, " %s", node
->name ());
604 node
->address_taken
= false;
606 if (cgraph_local_node_p (node
))
608 node
->local
.local
= true;
610 fprintf (file
, " (local)");
615 fprintf (file
, "\n");
617 #ifdef ENABLE_CHECKING
621 /* If we removed something, perhaps profile could be improved. */
622 if (changed
&& optimize
&& inline_edge_summary_vec
.exists ())
623 FOR_EACH_DEFINED_FUNCTION (node
)
624 ipa_propagate_frequency (node
);
626 timevar_pop (TV_IPA_UNREACHABLE
);
630 /* Discover variables that have no longer address taken or that are read only
631 and update their flags.
633 FIXME: This can not be done in between gimplify and omp_expand since
634 readonly flag plays role on what is shared and what is not. Currently we do
635 this transformation as part of whole program visibility and re-do at
636 ipa-reference pass (to take into account clonning), but it would
637 make sense to do it before early optimizations. */
640 ipa_discover_readonly_nonaddressable_vars (void)
644 fprintf (dump_file
, "Clearing variable flags:");
645 FOR_EACH_VARIABLE (vnode
)
646 if (vnode
->definition
&& varpool_all_refs_explicit_p (vnode
)
647 && (TREE_ADDRESSABLE (vnode
->decl
)
648 || !TREE_READONLY (vnode
->decl
)))
650 bool written
= false;
651 bool address_taken
= false;
654 for (i
= 0; ipa_ref_list_referring_iterate (&vnode
->ref_list
,
656 && (!written
|| !address_taken
); i
++)
660 address_taken
= true;
668 if (TREE_ADDRESSABLE (vnode
->decl
) && !address_taken
)
671 fprintf (dump_file
, " %s (addressable)", vnode
->name ());
672 TREE_ADDRESSABLE (vnode
->decl
) = 0;
674 if (!TREE_READONLY (vnode
->decl
) && !address_taken
&& !written
675 /* Making variable in explicit section readonly can cause section
677 See e.g. gcc.c-torture/compile/pr23237.c */
678 && DECL_SECTION_NAME (vnode
->decl
) == NULL
)
681 fprintf (dump_file
, " %s (read-only)", vnode
->name ());
682 TREE_READONLY (vnode
->decl
) = 1;
686 fprintf (dump_file
, "\n");
689 /* Return true when there is a reference to node and it is not vtable. */
691 address_taken_from_non_vtable_p (symtab_node
*node
)
695 for (i
= 0; ipa_ref_list_referring_iterate (&node
->ref_list
,
697 if (ref
->use
== IPA_REF_ADDR
)
700 if (is_a
<cgraph_node
> (ref
->referring
))
702 node
= ipa_ref_referring_varpool_node (ref
);
703 if (!DECL_VIRTUAL_P (node
->decl
))
709 /* A helper for comdat_can_be_unshared_p. */
712 comdat_can_be_unshared_p_1 (symtab_node
*node
)
714 if (!node
->externally_visible
)
716 /* When address is taken, we don't know if equality comparison won't
717 break eventually. Exception are virutal functions, C++
718 constructors/destructors and vtables, where this is not possible by
719 language standard. */
720 if (!DECL_VIRTUAL_P (node
->decl
)
721 && (TREE_CODE (node
->decl
) != FUNCTION_DECL
722 || (!DECL_CXX_CONSTRUCTOR_P (node
->decl
)
723 && !DECL_CXX_DESTRUCTOR_P (node
->decl
)))
724 && address_taken_from_non_vtable_p (node
))
727 /* If the symbol is used in some weird way, better to not touch it. */
728 if (node
->force_output
)
731 /* Explicit instantiations needs to be output when possibly
733 if (node
->forced_by_abi
734 && TREE_PUBLIC (node
->decl
)
735 && (node
->resolution
!= LDPR_PREVAILING_DEF_IRONLY
736 && !flag_whole_program
))
739 /* Non-readonly and volatile variables can not be duplicated. */
740 if (is_a
<varpool_node
> (node
)
741 && (!TREE_READONLY (node
->decl
)
742 || TREE_THIS_VOLATILE (node
->decl
)))
747 /* COMDAT functions must be shared only if they have address taken,
748 otherwise we can produce our own private implementation with
750 Return true when turning COMDAT functoin static can not lead to wrong
751 code when the resulting object links with a library defining same COMDAT.
753 Virtual functions do have their addresses taken from the vtables,
754 but in C++ there is no way to compare their addresses for equality. */
757 comdat_can_be_unshared_p (symtab_node
*node
)
759 if (!comdat_can_be_unshared_p_1 (node
))
761 if (node
->same_comdat_group
)
765 /* If more than one function is in the same COMDAT group, it must
766 be shared even if just one function in the comdat group has
768 for (next
= node
->same_comdat_group
;
769 next
!= node
; next
= next
->same_comdat_group
)
770 if (!comdat_can_be_unshared_p_1 (next
))
776 /* Return true when function NODE should be considered externally visible. */
779 cgraph_externally_visible_p (struct cgraph_node
*node
,
782 if (!node
->definition
)
784 if (!TREE_PUBLIC (node
->decl
)
785 || DECL_EXTERNAL (node
->decl
))
788 /* Do not try to localize built-in functions yet. One of problems is that we
789 end up mangling their asm for WHOPR that makes it impossible to call them
790 using the implicit built-in declarations anymore. Similarly this enables
791 us to remove them as unreachable before actual calls may appear during
792 expansion or folding. */
793 if (DECL_BUILT_IN (node
->decl
))
796 /* If linker counts on us, we must preserve the function. */
797 if (symtab_used_from_object_file_p (node
))
799 if (DECL_PRESERVE_P (node
->decl
))
801 if (lookup_attribute ("externally_visible",
802 DECL_ATTRIBUTES (node
->decl
)))
804 if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
805 && lookup_attribute ("dllexport",
806 DECL_ATTRIBUTES (node
->decl
)))
808 if (node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
)
810 /* When doing LTO or whole program, we can bring COMDAT functoins static.
811 This improves code quality and we know we will duplicate them at most twice
812 (in the case that we are not using plugin and link with object file
813 implementing same COMDAT) */
814 if ((in_lto_p
|| whole_program
)
815 && DECL_COMDAT (node
->decl
)
816 && comdat_can_be_unshared_p (node
))
819 /* When doing link time optimizations, hidden symbols become local. */
821 && (DECL_VISIBILITY (node
->decl
) == VISIBILITY_HIDDEN
822 || DECL_VISIBILITY (node
->decl
) == VISIBILITY_INTERNAL
)
823 /* Be sure that node is defined in IR file, not in other object
824 file. In that case we don't set used_from_other_object_file. */
827 else if (!whole_program
)
830 if (MAIN_NAME_P (DECL_NAME (node
->decl
)))
836 /* Return true when variable VNODE should be considered externally visible. */
839 varpool_externally_visible_p (varpool_node
*vnode
)
841 if (DECL_EXTERNAL (vnode
->decl
))
844 if (!TREE_PUBLIC (vnode
->decl
))
847 /* If linker counts on us, we must preserve the function. */
848 if (symtab_used_from_object_file_p (vnode
))
851 if (DECL_HARD_REGISTER (vnode
->decl
))
853 if (DECL_PRESERVE_P (vnode
->decl
))
855 if (lookup_attribute ("externally_visible",
856 DECL_ATTRIBUTES (vnode
->decl
)))
858 if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
859 && lookup_attribute ("dllexport",
860 DECL_ATTRIBUTES (vnode
->decl
)))
863 /* See if we have linker information about symbol not being used or
864 if we need to make guess based on the declaration.
866 Even if the linker clams the symbol is unused, never bring internal
867 symbols that are declared by user as used or externally visible.
868 This is needed for i.e. references from asm statements. */
869 if (symtab_used_from_object_file_p (vnode
))
871 if (vnode
->resolution
== LDPR_PREVAILING_DEF_IRONLY
)
874 /* As a special case, the COMDAT virtual tables can be unshared.
875 In LTO mode turn vtables into static variables. The variable is readonly,
876 so this does not enable more optimization, but referring static var
877 is faster for dynamic linking. Also this match logic hidding vtables
878 from LTO symbol tables. */
879 if ((in_lto_p
|| flag_whole_program
)
880 && DECL_COMDAT (vnode
->decl
)
881 && comdat_can_be_unshared_p (vnode
))
884 /* When doing link time optimizations, hidden symbols become local. */
886 && (DECL_VISIBILITY (vnode
->decl
) == VISIBILITY_HIDDEN
887 || DECL_VISIBILITY (vnode
->decl
) == VISIBILITY_INTERNAL
)
888 /* Be sure that node is defined in IR file, not in other object
889 file. In that case we don't set used_from_other_object_file. */
890 && vnode
->definition
)
892 else if (!flag_whole_program
)
895 /* Do not attempt to privatize COMDATS by default.
896 This would break linking with C++ libraries sharing
899 FIXME: We can do so for readonly vars with no address taken and
900 possibly also for vtables since no direct pointer comparsion is done.
901 It might be interesting to do so to reduce linking overhead. */
902 if (DECL_COMDAT (vnode
->decl
) || DECL_WEAK (vnode
->decl
))
907 /* Return true if reference to NODE can be replaced by a local alias.
908 Local aliases save dynamic linking overhead and enable more optimizations.
912 can_replace_by_local_alias (symtab_node
*node
)
914 return (symtab_node_availability (node
) > AVAIL_OVERWRITABLE
915 && !symtab_can_be_discarded (node
));
918 /* Mark visibility of all functions.
920 A local function is one whose calls can occur only in the current
921 compilation unit and all its calls are explicit, so we can change
922 its calling convention. We simply mark all static functions whose
923 address is not taken as local.
925 We also change the TREE_PUBLIC flag of all declarations that are public
926 in language point of view but we want to overwrite this default
927 via visibilities for the backend point of view. */
930 function_and_variable_visibility (bool whole_program
)
932 struct cgraph_node
*node
;
935 /* All aliases should be procssed at this point. */
936 gcc_checking_assert (!alias_pairs
|| !alias_pairs
->length ());
938 FOR_EACH_FUNCTION (node
)
940 int flags
= flags_from_decl_or_type (node
->decl
);
942 /* Optimize away PURE and CONST constructors and destructors. */
944 && (flags
& (ECF_CONST
| ECF_PURE
))
945 && !(flags
& ECF_LOOPING_CONST_OR_PURE
))
947 DECL_STATIC_CONSTRUCTOR (node
->decl
) = 0;
948 DECL_STATIC_DESTRUCTOR (node
->decl
) = 0;
951 /* Frontends and alias code marks nodes as needed before parsing is finished.
952 We may end up marking as node external nodes where this flag is meaningless
954 if (DECL_EXTERNAL (node
->decl
) || !node
->definition
)
956 node
->force_output
= 0;
957 node
->forced_by_abi
= 0;
960 /* C++ FE on lack of COMDAT support create local COMDAT functions
961 (that ought to be shared but can not due to object format
962 limitations). It is necessary to keep the flag to make rest of C++ FE
963 happy. Clear the flag here to avoid confusion in middle-end. */
964 if (DECL_COMDAT (node
->decl
) && !TREE_PUBLIC (node
->decl
))
965 DECL_COMDAT (node
->decl
) = 0;
967 /* For external decls stop tracking same_comdat_group. It doesn't matter
968 what comdat group they are in when they won't be emitted in this TU. */
969 if (node
->same_comdat_group
&& DECL_EXTERNAL (node
->decl
))
971 #ifdef ENABLE_CHECKING
974 for (n
= node
->same_comdat_group
;
976 n
= n
->same_comdat_group
)
977 /* If at least one of same comdat group functions is external,
978 all of them have to be, otherwise it is a front-end bug. */
979 gcc_assert (DECL_EXTERNAL (n
->decl
));
981 symtab_dissolve_same_comdat_group_list (node
);
983 gcc_assert ((!DECL_WEAK (node
->decl
)
984 && !DECL_COMDAT (node
->decl
))
985 || TREE_PUBLIC (node
->decl
)
987 || DECL_EXTERNAL (node
->decl
));
988 if (cgraph_externally_visible_p (node
, whole_program
))
990 gcc_assert (!node
->global
.inlined_to
);
991 node
->externally_visible
= true;
995 node
->externally_visible
= false;
996 node
->forced_by_abi
= false;
998 if (!node
->externally_visible
999 && node
->definition
&& !node
->weakref
1000 && !DECL_EXTERNAL (node
->decl
))
1002 gcc_assert (whole_program
|| in_lto_p
1003 || !TREE_PUBLIC (node
->decl
));
1004 node
->unique_name
= ((node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
1005 || node
->unique_name
1006 || node
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
1007 && TREE_PUBLIC (node
->decl
));
1008 node
->resolution
= LDPR_PREVAILING_DEF_IRONLY
;
1009 if (node
->same_comdat_group
&& TREE_PUBLIC (node
->decl
))
1011 symtab_node
*next
= node
;
1013 /* Set all members of comdat group local. */
1014 if (node
->same_comdat_group
)
1015 for (next
= node
->same_comdat_group
;
1017 next
= next
->same_comdat_group
)
1019 symtab_make_decl_local (next
->decl
);
1020 next
->unique_name
= ((next
->resolution
== LDPR_PREVAILING_DEF_IRONLY
1021 || next
->unique_name
1022 || next
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
1023 && TREE_PUBLIC (next
->decl
));
1025 /* cgraph_externally_visible_p has already checked all other nodes
1026 in the group and they will all be made local. We need to
1027 dissolve the group at once so that the predicate does not
1029 symtab_dissolve_same_comdat_group_list (node
);
1031 symtab_make_decl_local (node
->decl
);
1034 if (node
->thunk
.thunk_p
1035 && TREE_PUBLIC (node
->decl
))
1037 struct cgraph_node
*decl_node
= node
;
1039 decl_node
= cgraph_function_node (decl_node
->callees
->callee
, NULL
);
1041 /* Thunks have the same visibility as function they are attached to.
1042 Make sure the C++ front end set this up properly. */
1043 if (DECL_ONE_ONLY (decl_node
->decl
))
1045 gcc_checking_assert (DECL_COMDAT (node
->decl
)
1046 == DECL_COMDAT (decl_node
->decl
));
1047 gcc_checking_assert (DECL_COMDAT_GROUP (node
->decl
)
1048 == DECL_COMDAT_GROUP (decl_node
->decl
));
1049 gcc_checking_assert (node
->same_comdat_group
);
1051 node
->forced_by_abi
= decl_node
->forced_by_abi
;
1052 if (DECL_EXTERNAL (decl_node
->decl
))
1053 DECL_EXTERNAL (node
->decl
) = 1;
1056 /* If whole comdat group is used only within LTO code, we can dissolve it,
1057 we handle the unification ourselves.
1058 We keep COMDAT and weak so visibility out of DSO does not change.
1059 Later we may bring the symbols static if they are not exported. */
1060 if (DECL_ONE_ONLY (node
->decl
)
1061 && (node
->resolution
== LDPR_PREVAILING_DEF_IRONLY
1062 || node
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
))
1064 symtab_node
*next
= node
;
1066 if (node
->same_comdat_group
)
1067 for (next
= node
->same_comdat_group
;
1069 next
= next
->same_comdat_group
)
1070 if (next
->externally_visible
1071 && (next
->resolution
!= LDPR_PREVAILING_DEF_IRONLY
1072 && next
->resolution
!= LDPR_PREVAILING_DEF_IRONLY_EXP
))
1076 if (node
->same_comdat_group
)
1077 for (next
= node
->same_comdat_group
;
1079 next
= next
->same_comdat_group
)
1081 DECL_COMDAT_GROUP (next
->decl
) = NULL
;
1082 DECL_WEAK (next
->decl
) = false;
1084 DECL_COMDAT_GROUP (node
->decl
) = NULL
;
1085 symtab_dissolve_same_comdat_group_list (node
);
1089 FOR_EACH_DEFINED_FUNCTION (node
)
1091 node
->local
.local
|= cgraph_local_node_p (node
);
1093 /* If we know that function can not be overwritten by a different semantics
1094 and moreover its section can not be discarded, replace all direct calls
1095 by calls to an nonoverwritable alias. This make dynamic linking
1096 cheaper and enable more optimization.
1098 TODO: We can also update virtual tables. */
1099 if (node
->callers
&& can_replace_by_local_alias (node
))
1101 struct cgraph_node
*alias
= cgraph (symtab_nonoverwritable_alias (node
));
1103 if (alias
&& alias
!= node
)
1105 while (node
->callers
)
1107 struct cgraph_edge
*e
= node
->callers
;
1109 cgraph_redirect_edge_callee (e
, alias
);
1110 if (gimple_has_body_p (e
->caller
->decl
))
1112 push_cfun (DECL_STRUCT_FUNCTION (e
->caller
->decl
));
1113 cgraph_redirect_edge_call_stmt_to_callee (e
);
1120 FOR_EACH_VARIABLE (vnode
)
1122 /* weak flag makes no sense on local variables. */
1123 gcc_assert (!DECL_WEAK (vnode
->decl
)
1125 || TREE_PUBLIC (vnode
->decl
)
1126 || DECL_EXTERNAL (vnode
->decl
));
1127 /* In several cases declarations can not be common:
1129 - when declaration has initializer
1130 - when it is in weak
1131 - when it has specific section
1132 - when it resides in non-generic address space.
1133 - if declaration is local, it will get into .local common section
1134 so common flag is not needed. Frontends still produce these in
1135 certain cases, such as for:
1137 static int a __attribute__ ((common))
1139 Canonicalize things here and clear the redundant flag. */
1140 if (DECL_COMMON (vnode
->decl
)
1141 && (!(TREE_PUBLIC (vnode
->decl
)
1142 || DECL_EXTERNAL (vnode
->decl
))
1143 || (DECL_INITIAL (vnode
->decl
)
1144 && DECL_INITIAL (vnode
->decl
) != error_mark_node
)
1145 || DECL_WEAK (vnode
->decl
)
1146 || DECL_SECTION_NAME (vnode
->decl
) != NULL
1147 || ! (ADDR_SPACE_GENERIC_P
1148 (TYPE_ADDR_SPACE (TREE_TYPE (vnode
->decl
))))))
1149 DECL_COMMON (vnode
->decl
) = 0;
1151 FOR_EACH_DEFINED_VARIABLE (vnode
)
1153 if (!vnode
->definition
)
1155 if (varpool_externally_visible_p (vnode
))
1156 vnode
->externally_visible
= true;
1159 vnode
->externally_visible
= false;
1160 vnode
->forced_by_abi
= false;
1162 if (!vnode
->externally_visible
1165 gcc_assert (in_lto_p
|| whole_program
|| !TREE_PUBLIC (vnode
->decl
));
1166 vnode
->unique_name
= ((vnode
->resolution
== LDPR_PREVAILING_DEF_IRONLY
1167 || vnode
->resolution
== LDPR_PREVAILING_DEF_IRONLY_EXP
)
1168 && TREE_PUBLIC (vnode
->decl
));
1169 symtab_make_decl_local (vnode
->decl
);
1170 if (vnode
->same_comdat_group
)
1171 symtab_dissolve_same_comdat_group_list (vnode
);
1172 vnode
->resolution
= LDPR_PREVAILING_DEF_IRONLY
;
1178 fprintf (dump_file
, "\nMarking local functions:");
1179 FOR_EACH_DEFINED_FUNCTION (node
)
1180 if (node
->local
.local
)
1181 fprintf (dump_file
, " %s", node
->name ());
1182 fprintf (dump_file
, "\n\n");
1183 fprintf (dump_file
, "\nMarking externally visible functions:");
1184 FOR_EACH_DEFINED_FUNCTION (node
)
1185 if (node
->externally_visible
)
1186 fprintf (dump_file
, " %s", node
->name ());
1187 fprintf (dump_file
, "\n\n");
1188 fprintf (dump_file
, "\nMarking externally visible variables:");
1189 FOR_EACH_DEFINED_VARIABLE (vnode
)
1190 if (vnode
->externally_visible
)
1191 fprintf (dump_file
, " %s", vnode
->name ());
1192 fprintf (dump_file
, "\n\n");
1194 cgraph_function_flags_ready
= true;
1198 /* Local function pass handling visibilities. This happens before LTO streaming
1199 so in particular -fwhole-program should be ignored at this level. */
1202 local_function_and_variable_visibility (void)
1204 return function_and_variable_visibility (flag_whole_program
&& !flag_lto
);
1209 const pass_data pass_data_ipa_function_and_variable_visibility
=
1211 SIMPLE_IPA_PASS
, /* type */
1212 "visibility", /* name */
1213 OPTGROUP_NONE
, /* optinfo_flags */
1214 false, /* has_gate */
1215 true, /* has_execute */
1216 TV_CGRAPHOPT
, /* tv_id */
1217 0, /* properties_required */
1218 0, /* properties_provided */
1219 0, /* properties_destroyed */
1220 0, /* todo_flags_start */
1221 ( TODO_remove_functions
| TODO_dump_symtab
), /* todo_flags_finish */
1224 class pass_ipa_function_and_variable_visibility
: public simple_ipa_opt_pass
1227 pass_ipa_function_and_variable_visibility (gcc::context
*ctxt
)
1228 : simple_ipa_opt_pass (pass_data_ipa_function_and_variable_visibility
,
1232 /* opt_pass methods: */
1233 unsigned int execute () {
1234 return local_function_and_variable_visibility ();
1237 }; // class pass_ipa_function_and_variable_visibility
1241 simple_ipa_opt_pass
*
1242 make_pass_ipa_function_and_variable_visibility (gcc::context
*ctxt
)
1244 return new pass_ipa_function_and_variable_visibility (ctxt
);
1247 /* Free inline summary. */
1250 free_inline_summary (void)
1252 inline_free_summary ();
1258 const pass_data pass_data_ipa_free_inline_summary
=
1260 SIMPLE_IPA_PASS
, /* type */
1261 "*free_inline_summary", /* name */
1262 OPTGROUP_NONE
, /* optinfo_flags */
1263 false, /* has_gate */
1264 true, /* has_execute */
1265 TV_IPA_FREE_INLINE_SUMMARY
, /* tv_id */
1266 0, /* properties_required */
1267 0, /* properties_provided */
1268 0, /* properties_destroyed */
1269 0, /* todo_flags_start */
1270 0, /* todo_flags_finish */
1273 class pass_ipa_free_inline_summary
: public simple_ipa_opt_pass
1276 pass_ipa_free_inline_summary (gcc::context
*ctxt
)
1277 : simple_ipa_opt_pass (pass_data_ipa_free_inline_summary
, ctxt
)
1280 /* opt_pass methods: */
1281 unsigned int execute () { return free_inline_summary (); }
1283 }; // class pass_ipa_free_inline_summary
1287 simple_ipa_opt_pass
*
1288 make_pass_ipa_free_inline_summary (gcc::context
*ctxt
)
1290 return new pass_ipa_free_inline_summary (ctxt
);
1293 /* Do not re-run on ltrans stage. */
1296 gate_whole_program_function_and_variable_visibility (void)
1298 return !flag_ltrans
;
1301 /* Bring functionss local at LTO time with -fwhole-program. */
1304 whole_program_function_and_variable_visibility (void)
1306 function_and_variable_visibility (flag_whole_program
);
1308 ipa_discover_readonly_nonaddressable_vars ();
1314 const pass_data pass_data_ipa_whole_program_visibility
=
1316 IPA_PASS
, /* type */
1317 "whole-program", /* name */
1318 OPTGROUP_NONE
, /* optinfo_flags */
1319 true, /* has_gate */
1320 true, /* has_execute */
1321 TV_CGRAPHOPT
, /* tv_id */
1322 0, /* properties_required */
1323 0, /* properties_provided */
1324 0, /* properties_destroyed */
1325 0, /* todo_flags_start */
1326 ( TODO_remove_functions
| TODO_dump_symtab
), /* todo_flags_finish */
1329 class pass_ipa_whole_program_visibility
: public ipa_opt_pass_d
1332 pass_ipa_whole_program_visibility (gcc::context
*ctxt
)
1333 : ipa_opt_pass_d (pass_data_ipa_whole_program_visibility
, ctxt
,
1334 NULL
, /* generate_summary */
1335 NULL
, /* write_summary */
1336 NULL
, /* read_summary */
1337 NULL
, /* write_optimization_summary */
1338 NULL
, /* read_optimization_summary */
1339 NULL
, /* stmt_fixup */
1340 0, /* function_transform_todo_flags_start */
1341 NULL
, /* function_transform */
1342 NULL
) /* variable_transform */
1345 /* opt_pass methods: */
1347 return gate_whole_program_function_and_variable_visibility ();
1349 unsigned int execute () {
1350 return whole_program_function_and_variable_visibility ();
1353 }; // class pass_ipa_whole_program_visibility
1358 make_pass_ipa_whole_program_visibility (gcc::context
*ctxt
)
1360 return new pass_ipa_whole_program_visibility (ctxt
);
1363 /* Generate and emit a static constructor or destructor. WHICH must
1364 be one of 'I' (for a constructor) or 'D' (for a destructor). BODY
1365 is a STATEMENT_LIST containing GENERIC statements. PRIORITY is the
1366 initialization priority for this constructor or destructor.
1368 FINAL specify whether the externally visible name for collect2 should
1372 cgraph_build_static_cdtor_1 (char which
, tree body
, int priority
, bool final
)
1374 static int counter
= 0;
1376 tree decl
, name
, resdecl
;
1378 /* The priority is encoded in the constructor or destructor name.
1379 collect2 will sort the names and arrange that they are called at
1382 sprintf (which_buf
, "%c_%.5d_%d", which
, priority
, counter
++);
1384 /* Proudce sane name but one not recognizable by collect2, just for the
1385 case we fail to inline the function. */
1386 sprintf (which_buf
, "sub_%c_%.5d_%d", which
, priority
, counter
++);
1387 name
= get_file_function_name (which_buf
);
1389 decl
= build_decl (input_location
, FUNCTION_DECL
, name
,
1390 build_function_type_list (void_type_node
, NULL_TREE
));
1391 current_function_decl
= decl
;
1393 resdecl
= build_decl (input_location
,
1394 RESULT_DECL
, NULL_TREE
, void_type_node
);
1395 DECL_ARTIFICIAL (resdecl
) = 1;
1396 DECL_RESULT (decl
) = resdecl
;
1397 DECL_CONTEXT (resdecl
) = decl
;
1399 allocate_struct_function (decl
, false);
1401 TREE_STATIC (decl
) = 1;
1402 TREE_USED (decl
) = 1;
1403 DECL_ARTIFICIAL (decl
) = 1;
1404 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl
) = 1;
1405 DECL_SAVED_TREE (decl
) = body
;
1406 if (!targetm
.have_ctors_dtors
&& final
)
1408 TREE_PUBLIC (decl
) = 1;
1409 DECL_PRESERVE_P (decl
) = 1;
1411 DECL_UNINLINABLE (decl
) = 1;
1413 DECL_INITIAL (decl
) = make_node (BLOCK
);
1414 TREE_USED (DECL_INITIAL (decl
)) = 1;
1416 DECL_SOURCE_LOCATION (decl
) = input_location
;
1417 cfun
->function_end_locus
= input_location
;
1422 DECL_STATIC_CONSTRUCTOR (decl
) = 1;
1423 decl_init_priority_insert (decl
, priority
);
1426 DECL_STATIC_DESTRUCTOR (decl
) = 1;
1427 decl_fini_priority_insert (decl
, priority
);
1433 gimplify_function_tree (decl
);
1435 cgraph_add_new_function (decl
, false);
1438 current_function_decl
= NULL
;
1441 /* Generate and emit a static constructor or destructor. WHICH must
1442 be one of 'I' (for a constructor) or 'D' (for a destructor). BODY
1443 is a STATEMENT_LIST containing GENERIC statements. PRIORITY is the
1444 initialization priority for this constructor or destructor. */
1447 cgraph_build_static_cdtor (char which
, tree body
, int priority
)
1449 cgraph_build_static_cdtor_1 (which
, body
, priority
, false);
1452 /* A vector of FUNCTION_DECLs declared as static constructors. */
1453 static vec
<tree
> static_ctors
;
1454 /* A vector of FUNCTION_DECLs declared as static destructors. */
1455 static vec
<tree
> static_dtors
;
1457 /* When target does not have ctors and dtors, we call all constructor
1458 and destructor by special initialization/destruction function
1459 recognized by collect2.
1461 When we are going to build this function, collect all constructors and
1462 destructors and turn them into normal functions. */
1465 record_cdtor_fn (struct cgraph_node
*node
)
1467 if (DECL_STATIC_CONSTRUCTOR (node
->decl
))
1468 static_ctors
.safe_push (node
->decl
);
1469 if (DECL_STATIC_DESTRUCTOR (node
->decl
))
1470 static_dtors
.safe_push (node
->decl
);
1471 node
= cgraph_get_node (node
->decl
);
1472 DECL_DISREGARD_INLINE_LIMITS (node
->decl
) = 1;
1475 /* Define global constructors/destructor functions for the CDTORS, of
1476 which they are LEN. The CDTORS are sorted by initialization
1477 priority. If CTOR_P is true, these are constructors; otherwise,
1478 they are destructors. */
1481 build_cdtor (bool ctor_p
, vec
<tree
> cdtors
)
1484 size_t len
= cdtors
.length ();
1491 priority_type priority
;
1500 p
= ctor_p
? DECL_INIT_PRIORITY (fn
) : DECL_FINI_PRIORITY (fn
);
1503 else if (p
!= priority
)
1509 /* When there is only one cdtor and target supports them, do nothing. */
1511 && targetm
.have_ctors_dtors
)
1516 /* Find the next batch of constructors/destructors with the same
1517 initialization priority. */
1522 call
= build_call_expr (fn
, 0);
1524 DECL_STATIC_CONSTRUCTOR (fn
) = 0;
1526 DECL_STATIC_DESTRUCTOR (fn
) = 0;
1527 /* We do not want to optimize away pure/const calls here.
1528 When optimizing, these should be already removed, when not
1529 optimizing, we want user to be able to breakpoint in them. */
1530 TREE_SIDE_EFFECTS (call
) = 1;
1531 append_to_statement_list (call
, &body
);
1533 gcc_assert (body
!= NULL_TREE
);
1534 /* Generate a function to call all the function of like
1536 cgraph_build_static_cdtor_1 (ctor_p
? 'I' : 'D', body
, priority
, true);
1540 /* Comparison function for qsort. P1 and P2 are actually of type
1541 "tree *" and point to static constructors. DECL_INIT_PRIORITY is
1542 used to determine the sort order. */
1545 compare_ctor (const void *p1
, const void *p2
)
1552 f1
= *(const tree
*)p1
;
1553 f2
= *(const tree
*)p2
;
1554 priority1
= DECL_INIT_PRIORITY (f1
);
1555 priority2
= DECL_INIT_PRIORITY (f2
);
1557 if (priority1
< priority2
)
1559 else if (priority1
> priority2
)
1562 /* Ensure a stable sort. Constructors are executed in backwarding
1563 order to make LTO initialize braries first. */
1564 return DECL_UID (f2
) - DECL_UID (f1
);
1567 /* Comparison function for qsort. P1 and P2 are actually of type
1568 "tree *" and point to static destructors. DECL_FINI_PRIORITY is
1569 used to determine the sort order. */
1572 compare_dtor (const void *p1
, const void *p2
)
1579 f1
= *(const tree
*)p1
;
1580 f2
= *(const tree
*)p2
;
1581 priority1
= DECL_FINI_PRIORITY (f1
);
1582 priority2
= DECL_FINI_PRIORITY (f2
);
1584 if (priority1
< priority2
)
1586 else if (priority1
> priority2
)
1589 /* Ensure a stable sort. */
1590 return DECL_UID (f1
) - DECL_UID (f2
);
1593 /* Generate functions to call static constructors and destructors
1594 for targets that do not support .ctors/.dtors sections. These
1595 functions have magic names which are detected by collect2. */
1598 build_cdtor_fns (void)
1600 if (!static_ctors
.is_empty ())
1602 gcc_assert (!targetm
.have_ctors_dtors
|| in_lto_p
);
1603 static_ctors
.qsort (compare_ctor
);
1604 build_cdtor (/*ctor_p=*/true, static_ctors
);
1607 if (!static_dtors
.is_empty ())
1609 gcc_assert (!targetm
.have_ctors_dtors
|| in_lto_p
);
1610 static_dtors
.qsort (compare_dtor
);
1611 build_cdtor (/*ctor_p=*/false, static_dtors
);
1615 /* Look for constructors and destructors and produce function calling them.
1616 This is needed for targets not supporting ctors or dtors, but we perform the
1617 transformation also at linktime to merge possibly numerous
1618 constructors/destructors into single function to improve code locality and
1622 ipa_cdtor_merge (void)
1624 struct cgraph_node
*node
;
1625 FOR_EACH_DEFINED_FUNCTION (node
)
1626 if (DECL_STATIC_CONSTRUCTOR (node
->decl
)
1627 || DECL_STATIC_DESTRUCTOR (node
->decl
))
1628 record_cdtor_fn (node
);
1630 static_ctors
.release ();
1631 static_dtors
.release ();
1635 /* Perform the pass when we have no ctors/dtors support
1636 or at LTO time to merge multiple constructors into single
1640 gate_ipa_cdtor_merge (void)
1642 return !targetm
.have_ctors_dtors
|| (optimize
&& in_lto_p
);
1647 const pass_data pass_data_ipa_cdtor_merge
=
1649 IPA_PASS
, /* type */
1651 OPTGROUP_NONE
, /* optinfo_flags */
1652 true, /* has_gate */
1653 true, /* has_execute */
1654 TV_CGRAPHOPT
, /* tv_id */
1655 0, /* properties_required */
1656 0, /* properties_provided */
1657 0, /* properties_destroyed */
1658 0, /* todo_flags_start */
1659 0, /* todo_flags_finish */
1662 class pass_ipa_cdtor_merge
: public ipa_opt_pass_d
1665 pass_ipa_cdtor_merge (gcc::context
*ctxt
)
1666 : ipa_opt_pass_d (pass_data_ipa_cdtor_merge
, ctxt
,
1667 NULL
, /* generate_summary */
1668 NULL
, /* write_summary */
1669 NULL
, /* read_summary */
1670 NULL
, /* write_optimization_summary */
1671 NULL
, /* read_optimization_summary */
1672 NULL
, /* stmt_fixup */
1673 0, /* function_transform_todo_flags_start */
1674 NULL
, /* function_transform */
1675 NULL
) /* variable_transform */
1678 /* opt_pass methods: */
1679 bool gate () { return gate_ipa_cdtor_merge (); }
1680 unsigned int execute () { return ipa_cdtor_merge (); }
1682 }; // class pass_ipa_cdtor_merge
1687 make_pass_ipa_cdtor_merge (gcc::context
*ctxt
)
1689 return new pass_ipa_cdtor_merge (ctxt
);