1 /* Basic IPA utilities for type inheritance graph construction and
3 Copyright (C) 2013-2014 Free Software Foundation, Inc.
4 Contributed by Jan Hubicka
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 ODR = One Definition Rule
24 In short, the ODR states that:
25 1 In any translation unit, a template, type, function, or object can
26 have no more than one definition. Some of these can have any number
27 of declarations. A definition provides an instance.
28 2 In the entire program, an object or non-inline function cannot have
29 more than one definition; if an object or function is used, it must
30 have exactly one definition. You can declare an object or function
31 that is never used, in which case you don't have to provide
32 a definition. In no event can there be more than one definition.
33 3 Some things, like types, templates, and extern inline functions, can
34 be defined in more than one translation unit. For a given entity,
35 each definition must be the same. Non-extern objects and functions
36 in different translation units are different entities, even if their
37 names and types are the same.
40 This is the Gimple representation of type information of a polymorphic call.
41 It contains two parameters:
42 otr_type is a type of class whose method is called.
43 otr_token is the index into virtual table where address is taken.
46 This is the type inheritance information attached to each tree
47 RECORD_TYPE by the C++ frotend. It provides information about base
48 types and virtual tables.
50 BINFO is linked to the RECORD_TYPE by TYPE_BINFO.
51 BINFO also links to its type by BINFO_TYPE and to the virtual table by
54 Base types of a given type are enumerated by BINFO_BASE_BINFO
55 vector. Members of this vectors are not BINFOs associated
56 with a base type. Rather they are new copies of BINFOs
57 (base BINFOs). Their virtual tables may differ from
58 virtual table of the base type. Also BINFO_OFFSET specifies
59 offset of the base within the type.
61 In the case of single inheritance, the virtual table is shared
62 and BINFO_VTABLE of base BINFO is NULL. In the case of multiple
63 inheritance the individual virtual tables are pointer to by
64 BINFO_VTABLE of base binfos (that differs of BINFO_VTABLE of
65 binfo associated to the base type).
67 BINFO lookup for a given base type and offset can be done by
68 get_binfo_at_offset. It returns proper BINFO whose virtual table
69 can be used for lookup of virtual methods associated with the
73 This is an index of virtual method in virtual table associated
74 to the type defining it. Token can be looked up from OBJ_TYPE_REF
75 or from DECL_VINDEX of a given virtual table.
77 polymorphic (indirect) call
78 This is callgraph represention of virtual method call. Every
79 polymorphic call contains otr_type and otr_token taken from
80 original OBJ_TYPE_REF at callgraph construction time.
84 build_type_inheritance_graph triggers a construction of the type inheritance
87 We reconstruct it based on types of methods we see in the unit.
88 This means that the graph is not complete. Types with no methods are not
89 inserted into the graph. Also types without virtual methods are not
90 represented at all, though it may be easy to add this.
92 The inheritance graph is represented as follows:
94 Vertices are structures odr_type. Every odr_type may correspond
95 to one or more tree type nodes that are equivalent by ODR rule.
96 (the multiple type nodes appear only with linktime optimization)
98 Edges are represented by odr_type->base and odr_type->derived_types.
99 At the moment we do not track offsets of types for multiple inheritance.
102 possible_polymorphic_call_targets returns, given an parameters found in
103 indirect polymorphic edge all possible polymorphic call targets of the call.
105 pass_ipa_devirt performs simple speculative devirtualization.
110 #include "coretypes.h"
113 #include "print-tree.h"
117 #include "tree-pass.h"
118 #include "hash-set.h"
120 #include "hash-table.h"
122 #include "tree-pretty-print.h"
123 #include "ipa-utils.h"
124 #include "tree-ssa-alias.h"
125 #include "internal-fn.h"
126 #include "gimple-fold.h"
127 #include "gimple-expr.h"
129 #include "ipa-inline.h"
130 #include "diagnostic.h"
131 #include "tree-dfa.h"
132 #include "demangle.h"
134 #include "stor-layout.h"
137 static bool odr_types_equivalent_p (tree
, tree
, bool, bool *,
140 static bool odr_violation_reported
= false;
142 /* Dummy polymorphic call context. */
144 const ipa_polymorphic_call_context ipa_dummy_polymorphic_call_context
145 = {0, 0, NULL
, NULL
, false, true, true};
147 /* Pointer set of all call targets appearing in the cache. */
148 static hash_set
<cgraph_node
*> *cached_polymorphic_call_targets
;
150 /* The node of type inheritance graph. For each type unique in
151 One Defintion Rule (ODR) sense, we produce one node linking all
152 main variants of types equivalent to it, bases and derived types. */
154 struct GTY(()) odr_type_d
158 /* All bases; built only for main variants of types */
159 vec
<odr_type
> GTY((skip
)) bases
;
160 /* All derrived types with virtual methods seen in unit;
161 built only for main variants oftypes */
162 vec
<odr_type
> GTY((skip
)) derived_types
;
164 /* All equivalent types, if more than one. */
165 vec
<tree
, va_gc
> *types
;
166 /* Set of all equivalent types, if NON-NULL. */
167 hash_set
<tree
> * GTY((skip
)) types_set
;
169 /* Unique ID indexing the type in odr_types array. */
171 /* Is it in anonymous namespace? */
172 bool anonymous_namespace
;
173 /* Do we know about all derivations of given type? */
174 bool all_derivations_known
;
175 /* Did we report ODR violation here? */
179 static bool contains_type_p (tree
, HOST_WIDE_INT
, tree
);
182 /* Return true if BINFO corresponds to a type with virtual methods.
184 Every type has several BINFOs. One is the BINFO associated by the type
185 while other represents bases of derived types. The BINFOs representing
186 bases do not have BINFO_VTABLE pointer set when this is the single
187 inheritance (because vtables are shared). Look up the BINFO of type
188 and check presence of its vtable. */
191 polymorphic_type_binfo_p (tree binfo
)
193 /* See if BINFO's type has an virtual table associtated with it. */
194 return BINFO_VTABLE (TYPE_BINFO (BINFO_TYPE (binfo
)));
197 /* Return TRUE if all derived types of T are known and thus
198 we may consider the walk of derived type complete.
200 This is typically true only for final anonymous namespace types and types
201 defined within functions (that may be COMDAT and thus shared across units,
202 but with the same set of derived types). */
205 type_all_derivations_known_p (tree t
)
207 if (TYPE_FINAL_P (t
))
211 if (type_in_anonymous_namespace_p (t
))
213 return (decl_function_context (TYPE_NAME (t
)) != NULL
);
216 /* Return TURE if type's constructors are all visible. */
219 type_all_ctors_visible_p (tree t
)
222 && cgraph_state
>= CGRAPH_STATE_CONSTRUCTION
223 /* We can not always use type_all_derivations_known_p.
224 For function local types we must assume case where
225 the function is COMDAT and shared in between units.
227 TODO: These cases are quite easy to get, but we need
228 to keep track of C++ privatizing via -Wno-weak
229 as well as the IPA privatizing. */
230 && type_in_anonymous_namespace_p (t
);
233 /* Return TRUE if type may have instance. */
236 type_possibly_instantiated_p (tree t
)
241 /* TODO: Add abstract types here. */
242 if (!type_all_ctors_visible_p (t
))
245 vtable
= BINFO_VTABLE (TYPE_BINFO (t
));
246 if (TREE_CODE (vtable
) == POINTER_PLUS_EXPR
)
247 vtable
= TREE_OPERAND (TREE_OPERAND (vtable
, 0), 0);
248 vnode
= varpool_node::get (vtable
);
249 return vnode
&& vnode
->definition
;
252 /* One Definition Rule hashtable helpers. */
256 typedef odr_type_d value_type
;
257 typedef union tree_node compare_type
;
258 static inline hashval_t
hash (const value_type
*);
259 static inline bool equal (const value_type
*, const compare_type
*);
260 static inline void remove (value_type
*);
263 /* Return type that was declared with T's name so that T is an
264 qualified variant of it. */
267 main_odr_variant (const_tree t
)
269 if (TYPE_NAME (t
) && TREE_CODE (TYPE_NAME (t
)) == TYPE_DECL
)
270 return TREE_TYPE (TYPE_NAME (t
));
271 /* Unnamed types and non-C++ produced types can be compared by variants. */
273 return TYPE_MAIN_VARIANT (t
);
276 /* Produce hash based on type name. */
279 hash_type_name (tree t
)
281 gcc_checking_assert (main_odr_variant (t
) == t
);
283 /* If not in LTO, all main variants are unique, so we can do
286 return htab_hash_pointer (t
);
288 /* Anonymous types are unique. */
289 if (type_in_anonymous_namespace_p (t
))
290 return htab_hash_pointer (t
);
292 /* For polymorphic types, we can simply hash the virtual table. */
293 if (TREE_CODE (t
) == RECORD_TYPE
294 && TYPE_BINFO (t
) && BINFO_VTABLE (TYPE_BINFO (t
)))
296 tree v
= BINFO_VTABLE (TYPE_BINFO (t
));
299 if (TREE_CODE (v
) == POINTER_PLUS_EXPR
)
301 hash
= TREE_INT_CST_LOW (TREE_OPERAND (v
, 1));
302 v
= TREE_OPERAND (TREE_OPERAND (v
, 0), 0);
305 v
= DECL_ASSEMBLER_NAME (v
);
306 hash
= iterative_hash_hashval_t (hash
, htab_hash_pointer (v
));
310 /* Rest is not implemented yet. */
314 /* Return the computed hashcode for ODR_TYPE. */
317 odr_hasher::hash (const value_type
*odr_type
)
319 return hash_type_name (odr_type
->type
);
322 /* For languages with One Definition Rule, work out if
323 types are the same based on their name.
325 This is non-trivial for LTO where minnor differences in
326 the type representation may have prevented type merging
327 to merge two copies of otherwise equivalent type.
329 Until we start streaming mangled type names, this function works
330 only for polymorphic types. */
333 types_same_for_odr (const_tree type1
, const_tree type2
)
335 gcc_checking_assert (TYPE_P (type1
) && TYPE_P (type2
));
337 type1
= main_odr_variant (type1
);
338 type2
= main_odr_variant (type2
);
346 /* Check for anonymous namespaces. Those have !TREE_PUBLIC
347 on the corresponding TYPE_STUB_DECL. */
348 if (type_in_anonymous_namespace_p (type1
)
349 || type_in_anonymous_namespace_p (type2
))
352 /* See if types are obvoiusly different (i.e. different codes
353 or polymorphis wrt non-polymorphic). This is not strictly correct
354 for ODR violating programs, but we can't do better without streaming
356 if (TREE_CODE (type1
) != TREE_CODE (type2
))
358 if (TREE_CODE (type1
) == RECORD_TYPE
359 && (TYPE_BINFO (type1
) == NULL_TREE
) != (TYPE_BINFO (type1
) == NULL_TREE
))
361 if (TREE_CODE (type1
) == RECORD_TYPE
&& TYPE_BINFO (type1
)
362 && (BINFO_VTABLE (TYPE_BINFO (type1
)) == NULL_TREE
)
363 != (BINFO_VTABLE (TYPE_BINFO (type2
)) == NULL_TREE
))
366 /* At the moment we have no way to establish ODR equivlaence at LTO
367 other than comparing virtual table pointrs of polymorphic types.
368 Eventually we should start saving mangled names in TYPE_NAME.
369 Then this condition will become non-trivial. */
371 if (TREE_CODE (type1
) == RECORD_TYPE
372 && TYPE_BINFO (type1
) && TYPE_BINFO (type2
)
373 && BINFO_VTABLE (TYPE_BINFO (type1
))
374 && BINFO_VTABLE (TYPE_BINFO (type2
)))
376 tree v1
= BINFO_VTABLE (TYPE_BINFO (type1
));
377 tree v2
= BINFO_VTABLE (TYPE_BINFO (type2
));
378 gcc_assert (TREE_CODE (v1
) == POINTER_PLUS_EXPR
379 && TREE_CODE (v2
) == POINTER_PLUS_EXPR
);
380 return (operand_equal_p (TREE_OPERAND (v1
, 1),
381 TREE_OPERAND (v2
, 1), 0)
382 && DECL_ASSEMBLER_NAME
383 (TREE_OPERAND (TREE_OPERAND (v1
, 0), 0))
384 == DECL_ASSEMBLER_NAME
385 (TREE_OPERAND (TREE_OPERAND (v2
, 0), 0)));
391 /* Compare types T1 and T2 and return true if they are
395 odr_hasher::equal (const value_type
*t1
, const compare_type
*ct2
)
397 tree t2
= const_cast <tree
> (ct2
);
399 gcc_checking_assert (main_odr_variant (t2
) == t2
);
404 return types_same_for_odr (t1
->type
, t2
);
407 /* Free ODR type V. */
410 odr_hasher::remove (value_type
*v
)
413 v
->derived_types
.release ();
419 /* ODR type hash used to lookup ODR type based on tree type node. */
421 typedef hash_table
<odr_hasher
> odr_hash_type
;
422 static odr_hash_type
*odr_hash
;
424 /* ODR types are also stored into ODR_TYPE vector to allow consistent
425 walking. Bases appear before derived types. Vector is garbage collected
426 so we won't end up visiting empty types. */
428 static GTY(()) vec
<odr_type
, va_gc
> *odr_types_ptr
;
429 #define odr_types (*odr_types_ptr)
431 /* Set TYPE_BINFO of TYPE and its variants to BINFO. */
433 set_type_binfo (tree type
, tree binfo
)
435 for (; type
; type
= TYPE_NEXT_VARIANT (type
))
436 if (COMPLETE_TYPE_P (type
))
437 TYPE_BINFO (type
) = binfo
;
439 gcc_assert (!TYPE_BINFO (type
));
442 /* Compare T2 and T2 based on name or structure. */
445 odr_subtypes_equivalent_p (tree t1
, tree t2
, hash_set
<tree
> *visited
)
449 /* This can happen in incomplete types that should be handled earlier. */
450 gcc_assert (t1
&& t2
);
452 t1
= main_odr_variant (t1
);
453 t2
= main_odr_variant (t2
);
456 if (TREE_CODE (t1
) != TREE_CODE (t2
))
458 if ((TYPE_NAME (t1
) == NULL_TREE
) != (TYPE_NAME (t2
) == NULL_TREE
))
460 if (TYPE_NAME (t1
) && DECL_NAME (TYPE_NAME (t1
)) != DECL_NAME (TYPE_NAME (t2
)))
463 /* Anonymous namespace types must match exactly. */
464 an1
= type_in_anonymous_namespace_p (t1
);
465 an2
= type_in_anonymous_namespace_p (t2
);
466 if (an1
!= an2
|| an1
)
469 /* For types where we can not establish ODR equivalency, recurse and deeply
471 if (TREE_CODE (t1
) != RECORD_TYPE
472 || !TYPE_BINFO (t1
) || !TYPE_BINFO (t2
)
473 || !polymorphic_type_binfo_p (TYPE_BINFO (t1
))
474 || !polymorphic_type_binfo_p (TYPE_BINFO (t2
)))
476 /* This should really be a pair hash, but for the moment we do not need
477 100% reliability and it would be better to compare all ODR types so
478 recursion here is needed only for component types. */
479 if (visited
->add (t1
))
481 return odr_types_equivalent_p (t1
, t2
, false, NULL
, visited
);
483 return types_same_for_odr (t1
, t2
);
486 /* Output ODR violation warning about T1 and T2 with REASON.
487 Display location of ST1 and ST2 if REASON speaks about field or
489 If WARN is false, do nothing. Set WARNED if warning was indeed
493 warn_odr (tree t1
, tree t2
, tree st1
, tree st2
,
494 bool warn
, bool *warned
, const char *reason
)
496 tree decl2
= TYPE_NAME (t2
);
500 if (!warning_at (DECL_SOURCE_LOCATION (TYPE_NAME (t1
)), OPT_Wodr
,
501 "type %qT violates one definition rule",
506 else if (TREE_CODE (st1
) == FIELD_DECL
)
508 inform (DECL_SOURCE_LOCATION (decl2
),
509 "a different type is defined in another translation unit");
510 inform (DECL_SOURCE_LOCATION (st1
),
511 "the first difference of corresponding definitions is field %qD",
515 else if (TREE_CODE (st1
) == FUNCTION_DECL
)
517 inform (DECL_SOURCE_LOCATION (decl2
),
518 "a different type is defined in another translation unit");
519 inform (DECL_SOURCE_LOCATION (st1
),
520 "the first difference of corresponding definitions is method %qD",
526 inform (DECL_SOURCE_LOCATION (decl2
), reason
);
532 /* We already warned about ODR mismatch. T1 and T2 ought to be equivalent
533 because they are used on same place in ODR matching types.
534 They are not; inform the user. */
537 warn_types_mismatch (tree t1
, tree t2
)
539 if (!TYPE_NAME (t1
) || !TYPE_NAME (t2
))
541 /* In Firefox it is a common bug to have same types but in
542 different namespaces. Be a bit more informative on
544 if (TYPE_CONTEXT (t1
) && TYPE_CONTEXT (t2
)
545 && (((TREE_CODE (TYPE_CONTEXT (t1
)) == NAMESPACE_DECL
)
546 != (TREE_CODE (TYPE_CONTEXT (t2
)) == NAMESPACE_DECL
))
547 || (TREE_CODE (TYPE_CONTEXT (t1
)) == NAMESPACE_DECL
548 && (DECL_NAME (TYPE_CONTEXT (t1
)) !=
549 DECL_NAME (TYPE_CONTEXT (t2
))))))
550 inform (DECL_SOURCE_LOCATION (TYPE_NAME (t1
)),
551 "type %qT should match type %qT but is defined "
552 "in different namespace ",
555 inform (DECL_SOURCE_LOCATION (TYPE_NAME (t1
)),
556 "type %qT should match type %qT",
558 inform (DECL_SOURCE_LOCATION (TYPE_NAME (t2
)),
559 "the incompatible type is defined here");
562 /* Compare T1 and T2, report ODR violations if WARN is true and set
563 WARNED to true if anything is reported. Return true if types match.
564 If true is returned, the types are also compatible in the sense of
565 gimple_canonical_types_compatible_p. */
568 odr_types_equivalent_p (tree t1
, tree t2
, bool warn
, bool *warned
, hash_set
<tree
> *visited
)
570 /* Check first for the obvious case of pointer identity. */
573 gcc_assert (!type_in_anonymous_namespace_p (t1
));
574 gcc_assert (!type_in_anonymous_namespace_p (t2
));
576 /* Can't be the same type if the types don't have the same code. */
577 if (TREE_CODE (t1
) != TREE_CODE (t2
))
579 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
580 G_("a different type is defined in another translation unit"));
584 if (TYPE_QUALS (t1
) != TYPE_QUALS (t2
))
586 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
587 G_("a type with different qualifiers is defined in another "
588 "translation unit"));
592 if (comp_type_attributes (t1
, t2
) != 1)
594 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
595 G_("a type with attributes "
596 "is defined in another translation unit"));
600 if (TREE_CODE (t1
) == ENUMERAL_TYPE
)
603 for (v1
= TYPE_VALUES (t1
), v2
= TYPE_VALUES (t2
);
604 v1
&& v2
; v1
= TREE_CHAIN (v1
), v2
= TREE_CHAIN (v2
))
606 if (TREE_PURPOSE (v1
) != TREE_PURPOSE (v2
))
608 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
609 G_("an enum with different value name"
610 " is defined in another translation unit"));
613 if (TREE_VALUE (v1
) != TREE_VALUE (v2
)
614 && !operand_equal_p (DECL_INITIAL (TREE_VALUE (v1
)),
615 DECL_INITIAL (TREE_VALUE (v2
)), 0))
617 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
618 G_("an enum with different values is defined"
619 " in another translation unit"));
625 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
626 G_("an enum with mismatching number of values "
627 "is defined in another translation unit"));
632 /* Non-aggregate types can be handled cheaply. */
633 if (INTEGRAL_TYPE_P (t1
)
634 || SCALAR_FLOAT_TYPE_P (t1
)
635 || FIXED_POINT_TYPE_P (t1
)
636 || TREE_CODE (t1
) == VECTOR_TYPE
637 || TREE_CODE (t1
) == COMPLEX_TYPE
638 || TREE_CODE (t1
) == OFFSET_TYPE
639 || POINTER_TYPE_P (t1
))
641 if (TYPE_PRECISION (t1
) != TYPE_PRECISION (t2
))
643 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
644 G_("a type with different precision is defined "
645 "in another translation unit"));
648 if (TYPE_UNSIGNED (t1
) != TYPE_UNSIGNED (t2
))
650 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
651 G_("a type with different signedness is defined "
652 "in another translation unit"));
656 if (TREE_CODE (t1
) == INTEGER_TYPE
657 && TYPE_STRING_FLAG (t1
) != TYPE_STRING_FLAG (t2
))
659 /* char WRT uint_8? */
660 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
661 G_("a different type is defined in another "
662 "translation unit"));
666 /* For canonical type comparisons we do not want to build SCCs
667 so we cannot compare pointed-to types. But we can, for now,
668 require the same pointed-to type kind and match what
669 useless_type_conversion_p would do. */
670 if (POINTER_TYPE_P (t1
))
672 if (TYPE_ADDR_SPACE (TREE_TYPE (t1
))
673 != TYPE_ADDR_SPACE (TREE_TYPE (t2
)))
675 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
676 G_("it is defined as a pointer in different address "
677 "space in another translation unit"));
681 if (!odr_subtypes_equivalent_p (TREE_TYPE (t1
), TREE_TYPE (t2
), visited
))
683 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
684 G_("it is defined as a pointer to different type "
685 "in another translation unit"));
687 warn_types_mismatch (TREE_TYPE (t1
), TREE_TYPE (t2
));
692 /* Tail-recurse to components. */
693 if ((TREE_CODE (t1
) == VECTOR_TYPE
|| TREE_CODE (t1
) == COMPLEX_TYPE
)
694 && !odr_subtypes_equivalent_p (TREE_TYPE (t1
), TREE_TYPE (t2
), visited
))
696 /* Probably specific enough. */
697 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
698 G_("a different type is defined "
699 "in another translation unit"));
701 warn_types_mismatch (TREE_TYPE (t1
), TREE_TYPE (t2
));
705 gcc_assert (operand_equal_p (TYPE_SIZE (t1
), TYPE_SIZE (t2
), 0));
706 gcc_assert (operand_equal_p (TYPE_SIZE_UNIT (t1
),
707 TYPE_SIZE_UNIT (t2
), 0));
708 gcc_assert (TYPE_MODE (t1
) == TYPE_MODE (t2
));
713 /* Do type-specific comparisons. */
714 switch (TREE_CODE (t1
))
718 /* Array types are the same if the element types are the same and
719 the number of elements are the same. */
720 if (!odr_subtypes_equivalent_p (TREE_TYPE (t1
), TREE_TYPE (t2
), visited
))
722 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
723 G_("a different type is defined in another "
724 "translation unit"));
726 warn_types_mismatch (TREE_TYPE (t1
), TREE_TYPE (t2
));
728 gcc_assert (TYPE_STRING_FLAG (t1
) == TYPE_STRING_FLAG (t2
));
729 gcc_assert (TYPE_NONALIASED_COMPONENT (t1
)
730 == TYPE_NONALIASED_COMPONENT (t2
));
732 tree i1
= TYPE_DOMAIN (t1
);
733 tree i2
= TYPE_DOMAIN (t2
);
735 /* For an incomplete external array, the type domain can be
736 NULL_TREE. Check this condition also. */
737 if (i1
== NULL_TREE
|| i2
== NULL_TREE
)
740 tree min1
= TYPE_MIN_VALUE (i1
);
741 tree min2
= TYPE_MIN_VALUE (i2
);
742 tree max1
= TYPE_MAX_VALUE (i1
);
743 tree max2
= TYPE_MAX_VALUE (i2
);
745 /* In C++, minimums should be always 0. */
746 gcc_assert (min1
== min2
);
747 if (!operand_equal_p (max1
, max2
, 0))
749 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
750 G_("an array of different size is defined "
751 "in another translation unit"));
754 gcc_assert (operand_equal_p (TYPE_SIZE (t1
), TYPE_SIZE (t2
), 0));
755 gcc_assert (operand_equal_p (TYPE_SIZE_UNIT (t1
),
756 TYPE_SIZE_UNIT (t2
), 0));
762 /* Function types are the same if the return type and arguments types
764 if (!odr_subtypes_equivalent_p (TREE_TYPE (t1
), TREE_TYPE (t2
), visited
))
766 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
767 G_("has different return value "
768 "in another translation unit"));
770 warn_types_mismatch (TREE_TYPE (t1
), TREE_TYPE (t2
));
774 if (TYPE_ARG_TYPES (t1
) == TYPE_ARG_TYPES (t2
))
780 for (parms1
= TYPE_ARG_TYPES (t1
), parms2
= TYPE_ARG_TYPES (t2
);
782 parms1
= TREE_CHAIN (parms1
), parms2
= TREE_CHAIN (parms2
))
784 if (!odr_subtypes_equivalent_p
785 (TREE_VALUE (parms1
), TREE_VALUE (parms2
), visited
))
787 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
788 G_("has different parameters in another "
789 "translation unit"));
791 warn_types_mismatch (TREE_VALUE (parms1
),
792 TREE_VALUE (parms2
));
797 if (parms1
|| parms2
)
799 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
800 G_("has different parameters "
801 "in another translation unit"));
810 case QUAL_UNION_TYPE
:
814 /* For aggregate types, all the fields must be the same. */
815 if (COMPLETE_TYPE_P (t1
) && COMPLETE_TYPE_P (t2
))
817 for (f1
= TYPE_FIELDS (t1
), f2
= TYPE_FIELDS (t2
);
819 f1
= TREE_CHAIN (f1
), f2
= TREE_CHAIN (f2
))
821 /* Skip non-fields. */
822 while (f1
&& TREE_CODE (f1
) != FIELD_DECL
)
823 f1
= TREE_CHAIN (f1
);
824 while (f2
&& TREE_CODE (f2
) != FIELD_DECL
)
825 f2
= TREE_CHAIN (f2
);
828 if (DECL_ARTIFICIAL (f1
) != DECL_ARTIFICIAL (f2
))
830 if (DECL_NAME (f1
) != DECL_NAME (f2
)
831 && !DECL_ARTIFICIAL (f1
))
833 warn_odr (t1
, t2
, f1
, f2
, warn
, warned
,
834 G_("a field with different name is defined "
835 "in another translation unit"));
838 if (!odr_subtypes_equivalent_p (TREE_TYPE (f1
), TREE_TYPE (f2
), visited
))
840 /* Do not warn about artificial fields and just go into generic
841 field mismatch warning. */
842 if (DECL_ARTIFICIAL (f1
))
845 warn_odr (t1
, t2
, f1
, f2
, warn
, warned
,
846 G_("a field of same name but different type "
847 "is defined in another translation unit"));
849 warn_types_mismatch (TREE_TYPE (f1
), TREE_TYPE (f2
));
852 if (!gimple_compare_field_offset (f1
, f2
))
854 /* Do not warn about artificial fields and just go into generic
855 field mismatch warning. */
856 if (DECL_ARTIFICIAL (f1
))
858 warn_odr (t1
, t2
, t1
, t2
, warn
, warned
,
859 G_("fields has different layout "
860 "in another translation unit"));
863 gcc_assert (DECL_NONADDRESSABLE_P (f1
)
864 == DECL_NONADDRESSABLE_P (f2
));
867 /* If one aggregate has more fields than the other, they
871 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
872 G_("a type with different number of fields "
873 "is defined in another translation unit"));
876 if ((TYPE_MAIN_VARIANT (t1
) == t1
|| TYPE_MAIN_VARIANT (t2
) == t2
)
877 && (TYPE_METHODS (TYPE_MAIN_VARIANT (t1
))
878 != TYPE_METHODS (TYPE_MAIN_VARIANT (t2
))))
880 for (f1
= TYPE_METHODS (TYPE_MAIN_VARIANT (t1
)),
881 f2
= TYPE_METHODS (TYPE_MAIN_VARIANT (t2
));
882 f1
&& f2
; f1
= DECL_CHAIN (f1
), f2
= DECL_CHAIN (f2
))
884 if (DECL_ASSEMBLER_NAME (f1
) != DECL_ASSEMBLER_NAME (f2
))
886 warn_odr (t1
, t2
, f1
, f2
, warn
, warned
,
887 G_("a different method of same type "
888 "is defined in another translation unit"));
891 if (DECL_VIRTUAL_P (f1
) != DECL_VIRTUAL_P (f2
))
893 warn_odr (t1
, t2
, f1
, f2
, warn
, warned
,
894 G_("s definition that differs by virtual "
895 "keyword in another translation unit"));
898 if (DECL_VINDEX (f1
) != DECL_VINDEX (f2
))
900 warn_odr (t1
, t2
, f1
, f2
, warn
, warned
,
901 G_("virtual table layout differs in another "
902 "translation unit"));
905 if (odr_subtypes_equivalent_p (TREE_TYPE (f1
), TREE_TYPE (f2
), visited
))
907 warn_odr (t1
, t2
, f1
, f2
, warn
, warned
,
908 G_("method with incompatible type is defined "
909 "in another translation unit"));
915 warn_odr (t1
, t2
, NULL
, NULL
, warn
, warned
,
916 G_("a type with different number of methods "
917 "is defined in another translation unit"));
921 gcc_assert (operand_equal_p (TYPE_SIZE (t1
), TYPE_SIZE (t2
), 0));
922 gcc_assert (operand_equal_p (TYPE_SIZE_UNIT (t1
),
923 TYPE_SIZE_UNIT (t2
), 0));
934 /* TYPE is equivalent to VAL by ODR, but its tree representation differs
935 from VAL->type. This may happen in LTO where tree merging did not merge
936 all variants of the same type. It may or may not mean the ODR violation.
937 Add it to the list of duplicates and warn on some violations. */
940 add_type_duplicate (odr_type val
, tree type
)
942 bool build_bases
= false;
944 val
->types_set
= new hash_set
<tree
>;
946 /* Always prefer complete type to be the leader. */
947 if (!COMPLETE_TYPE_P (val
->type
)
948 && COMPLETE_TYPE_P (type
))
957 /* See if this duplicate is new. */
958 if (!val
->types_set
->add (type
))
961 bool base_mismatch
= false;
964 hash_set
<tree
> visited
;
966 gcc_assert (in_lto_p
);
967 vec_safe_push (val
->types
, type
);
969 /* First we compare memory layout. */
970 if (!odr_types_equivalent_p (val
->type
, type
, !flag_ltrans
&& !val
->odr_violated
,
974 odr_violation_reported
= true;
975 val
->odr_violated
= true;
976 if (cgraph_dump_file
)
978 fprintf (cgraph_dump_file
, "ODR violation\n");
980 print_node (cgraph_dump_file
, "", val
->type
, 0);
981 putc ('\n',cgraph_dump_file
);
982 print_node (cgraph_dump_file
, "", type
, 0);
983 putc ('\n',cgraph_dump_file
);
987 /* Next sanity check that bases are the same. If not, we will end
988 up producing wrong answers. */
989 if (COMPLETE_TYPE_P (type
) && COMPLETE_TYPE_P (val
->type
)
990 && TREE_CODE (val
->type
) == RECORD_TYPE
991 && TREE_CODE (type
) == RECORD_TYPE
992 && TYPE_BINFO (val
->type
) && TYPE_BINFO (type
))
994 for (j
= 0, i
= 0; i
< BINFO_N_BASE_BINFOS (TYPE_BINFO (type
)); i
++)
995 if (polymorphic_type_binfo_p (BINFO_BASE_BINFO (TYPE_BINFO (type
), i
)))
997 odr_type base
= get_odr_type
999 (BINFO_BASE_BINFO (TYPE_BINFO (type
),
1002 if (val
->bases
.length () <= j
|| val
->bases
[j
] != base
)
1003 base_mismatch
= true;
1009 odr_violation_reported
= true;
1011 if (!warned
&& !val
->odr_violated
)
1012 warn_odr (type
, val
->type
, NULL
, NULL
, !warned
, &warned
,
1013 "a type with the same name but different bases is "
1014 "defined in another translation unit");
1015 val
->odr_violated
= true;
1016 if (cgraph_dump_file
)
1018 fprintf (cgraph_dump_file
, "ODR bse violation or merging bug?\n");
1020 print_node (cgraph_dump_file
, "", val
->type
, 0);
1021 putc ('\n',cgraph_dump_file
);
1022 print_node (cgraph_dump_file
, "", type
, 0);
1023 putc ('\n',cgraph_dump_file
);
1028 /* Regularize things a little. During LTO same types may come with
1029 different BINFOs. Either because their virtual table was
1030 not merged by tree merging and only later at decl merging or
1031 because one type comes with external vtable, while other
1032 with internal. We want to merge equivalent binfos to conserve
1033 memory and streaming overhead.
1035 The external vtables are more harmful: they contain references
1036 to external declarations of methods that may be defined in the
1037 merged LTO unit. For this reason we absolutely need to remove
1038 them and replace by internal variants. Not doing so will lead
1039 to incomplete answers from possible_polymorphic_call_targets. */
1040 if (!flag_ltrans
&& merge
1041 && TREE_CODE (val
->type
) == RECORD_TYPE
1042 && TREE_CODE (type
) == RECORD_TYPE
1043 && TYPE_BINFO (val
->type
) && TYPE_BINFO (type
)
1044 && TYPE_MAIN_VARIANT (type
) == type
1045 && TYPE_MAIN_VARIANT (val
->type
) == val
->type
1046 && BINFO_VTABLE (TYPE_BINFO (val
->type
))
1047 && BINFO_VTABLE (TYPE_BINFO (type
)))
1049 tree master_binfo
= TYPE_BINFO (val
->type
);
1050 tree v1
= BINFO_VTABLE (master_binfo
);
1051 tree v2
= BINFO_VTABLE (TYPE_BINFO (type
));
1053 if (TREE_CODE (v1
) == POINTER_PLUS_EXPR
)
1055 gcc_assert (TREE_CODE (v2
) == POINTER_PLUS_EXPR
1056 && operand_equal_p (TREE_OPERAND (v1
, 1),
1057 TREE_OPERAND (v2
, 1), 0));
1058 v1
= TREE_OPERAND (TREE_OPERAND (v1
, 0), 0);
1059 v2
= TREE_OPERAND (TREE_OPERAND (v2
, 0), 0);
1061 gcc_assert (DECL_ASSEMBLER_NAME (v1
)
1062 == DECL_ASSEMBLER_NAME (v2
));
1064 if (DECL_EXTERNAL (v1
) && !DECL_EXTERNAL (v2
))
1068 set_type_binfo (val
->type
, TYPE_BINFO (type
));
1069 for (i
= 0; i
< val
->types
->length (); i
++)
1071 if (TYPE_BINFO ((*val
->types
)[i
])
1073 set_type_binfo ((*val
->types
)[i
], TYPE_BINFO (type
));
1075 BINFO_TYPE (TYPE_BINFO (type
)) = val
->type
;
1078 set_type_binfo (type
, master_binfo
);
1084 /* Get ODR type hash entry for TYPE. If INSERT is true, create
1085 possibly new entry. */
1088 get_odr_type (tree type
, bool insert
)
1093 bool build_bases
= false;
1094 bool insert_to_odr_array
= false;
1097 type
= main_odr_variant (type
);
1099 hash
= hash_type_name (type
);
1101 = odr_hash
->find_slot_with_hash (type
, hash
, insert
? INSERT
: NO_INSERT
);
1105 /* See if we already have entry for type. */
1110 /* With LTO we need to support multiple tree representation of
1111 the same ODR type. */
1112 if (val
->type
!= type
)
1113 build_bases
= add_type_duplicate (val
, type
);
1117 val
= ggc_cleared_alloc
<odr_type_d
> ();
1120 val
->derived_types
= vNULL
;
1121 val
->anonymous_namespace
= type_in_anonymous_namespace_p (type
);
1122 build_bases
= COMPLETE_TYPE_P (val
->type
);
1123 insert_to_odr_array
= true;
1126 if (build_bases
&& TREE_CODE (type
) == RECORD_TYPE
&& TYPE_BINFO (type
)
1127 && type
== TYPE_MAIN_VARIANT (type
))
1129 tree binfo
= TYPE_BINFO (type
);
1132 gcc_assert (BINFO_TYPE (TYPE_BINFO (val
->type
)) = type
);
1134 val
->all_derivations_known
= type_all_derivations_known_p (type
);
1136 for (i
= 0; i
< BINFO_N_BASE_BINFOS (binfo
); i
++)
1137 /* For now record only polymorphic types. other are
1138 pointless for devirtualization and we can not precisely
1139 determine ODR equivalency of these during LTO. */
1140 if (polymorphic_type_binfo_p (BINFO_BASE_BINFO (binfo
, i
)))
1142 odr_type base
= get_odr_type (BINFO_TYPE (BINFO_BASE_BINFO (binfo
,
1145 gcc_assert (TYPE_MAIN_VARIANT (base
->type
) == base
->type
);
1146 base
->derived_types
.safe_push (val
);
1147 val
->bases
.safe_push (base
);
1148 if (base
->id
> base_id
)
1152 /* Ensure that type always appears after bases. */
1153 if (insert_to_odr_array
)
1156 val
->id
= odr_types
.length ();
1157 vec_safe_push (odr_types_ptr
, val
);
1159 else if (base_id
> val
->id
)
1161 odr_types
[val
->id
] = 0;
1162 /* Be sure we did not recorded any derived types; these may need
1164 gcc_assert (val
->derived_types
.length() == 0);
1166 val
->id
= odr_types
.length ();
1167 vec_safe_push (odr_types_ptr
, val
);
1172 /* Dump ODR type T and all its derrived type. INDENT specify indentation for
1173 recusive printing. */
1176 dump_odr_type (FILE *f
, odr_type t
, int indent
=0)
1179 fprintf (f
, "%*s type %i: ", indent
* 2, "", t
->id
);
1180 print_generic_expr (f
, t
->type
, TDF_SLIM
);
1181 fprintf (f
, "%s", t
->anonymous_namespace
? " (anonymous namespace)":"");
1182 fprintf (f
, "%s\n", t
->all_derivations_known
? " (derivations known)":"");
1183 if (TYPE_NAME (t
->type
))
1185 fprintf (f
, "%*s defined at: %s:%i\n", indent
* 2, "",
1186 DECL_SOURCE_FILE (TYPE_NAME (t
->type
)),
1187 DECL_SOURCE_LINE (TYPE_NAME (t
->type
)));
1189 if (t
->bases
.length ())
1191 fprintf (f
, "%*s base odr type ids: ", indent
* 2, "");
1192 for (i
= 0; i
< t
->bases
.length (); i
++)
1193 fprintf (f
, " %i", t
->bases
[i
]->id
);
1196 if (t
->derived_types
.length ())
1198 fprintf (f
, "%*s derived types:\n", indent
* 2, "");
1199 for (i
= 0; i
< t
->derived_types
.length (); i
++)
1200 dump_odr_type (f
, t
->derived_types
[i
], indent
+ 1);
1205 /* Dump the type inheritance graph. */
1208 dump_type_inheritance_graph (FILE *f
)
1213 fprintf (f
, "\n\nType inheritance graph:\n");
1214 for (i
= 0; i
< odr_types
.length (); i
++)
1216 if (odr_types
[i
] && odr_types
[i
]->bases
.length () == 0)
1217 dump_odr_type (f
, odr_types
[i
]);
1219 for (i
= 0; i
< odr_types
.length (); i
++)
1221 if (odr_types
[i
] && odr_types
[i
]->types
&& odr_types
[i
]->types
->length ())
1224 fprintf (f
, "Duplicate tree types for odr type %i\n", i
);
1225 print_node (f
, "", odr_types
[i
]->type
, 0);
1226 for (j
= 0; j
< odr_types
[i
]->types
->length (); j
++)
1229 fprintf (f
, "duplicate #%i\n", j
);
1230 print_node (f
, "", (*odr_types
[i
]->types
)[j
], 0);
1231 t
= (*odr_types
[i
]->types
)[j
];
1232 while (TYPE_P (t
) && TYPE_CONTEXT (t
))
1234 t
= TYPE_CONTEXT (t
);
1235 print_node (f
, "", t
, 0);
1243 /* Given method type T, return type of class it belongs to.
1244 Lookup this pointer and get its type. */
1247 method_class_type (const_tree t
)
1249 tree first_parm_type
= TREE_VALUE (TYPE_ARG_TYPES (t
));
1250 gcc_assert (TREE_CODE (t
) == METHOD_TYPE
);
1252 return TREE_TYPE (first_parm_type
);
1255 /* Initialize IPA devirt and build inheritance tree graph. */
1258 build_type_inheritance_graph (void)
1260 struct symtab_node
*n
;
1261 FILE *inheritance_dump_file
;
1266 timevar_push (TV_IPA_INHERITANCE
);
1267 inheritance_dump_file
= dump_begin (TDI_inheritance
, &flags
);
1268 odr_hash
= new odr_hash_type (23);
1270 /* We reconstruct the graph starting of types of all methods seen in the
1273 if (is_a
<cgraph_node
*> (n
)
1274 && DECL_VIRTUAL_P (n
->decl
)
1275 && n
->real_symbol_p ())
1276 get_odr_type (TYPE_MAIN_VARIANT (method_class_type (TREE_TYPE (n
->decl
))),
1279 /* Look also for virtual tables of types that do not define any methods.
1281 We need it in a case where class B has virtual base of class A
1282 re-defining its virtual method and there is class C with no virtual
1283 methods with B as virtual base.
1285 Here we output B's virtual method in two variant - for non-virtual
1286 and virtual inheritance. B's virtual table has non-virtual version,
1287 while C's has virtual.
1289 For this reason we need to know about C in order to include both
1290 variants of B. More correctly, record_target_from_binfo should
1291 add both variants of the method when walking B, but we have no
1292 link in between them.
1294 We rely on fact that either the method is exported and thus we
1295 assume it is called externally or C is in anonymous namespace and
1296 thus we will see the vtable. */
1298 else if (is_a
<varpool_node
*> (n
)
1299 && DECL_VIRTUAL_P (n
->decl
)
1300 && TREE_CODE (DECL_CONTEXT (n
->decl
)) == RECORD_TYPE
1301 && TYPE_BINFO (DECL_CONTEXT (n
->decl
))
1302 && polymorphic_type_binfo_p (TYPE_BINFO (DECL_CONTEXT (n
->decl
))))
1303 get_odr_type (TYPE_MAIN_VARIANT (DECL_CONTEXT (n
->decl
)), true);
1304 if (inheritance_dump_file
)
1306 dump_type_inheritance_graph (inheritance_dump_file
);
1307 dump_end (TDI_inheritance
, inheritance_dump_file
);
1309 timevar_pop (TV_IPA_INHERITANCE
);
1312 /* Return true if N has reference from live virtual table
1313 (and thus can be a destination of polymorphic call).
1314 Be conservatively correct when callgraph is not built or
1315 if the method may be referred externally. */
1318 referenced_from_vtable_p (struct cgraph_node
*node
)
1321 struct ipa_ref
*ref
;
1324 if (node
->externally_visible
1325 || node
->used_from_other_partition
)
1328 /* Keep this test constant time.
1329 It is unlikely this can happen except for the case where speculative
1330 devirtualization introduced many speculative edges to this node.
1331 In this case the target is very likely alive anyway. */
1332 if (node
->ref_list
.referring
.length () > 100)
1335 /* We need references built. */
1336 if (cgraph_state
<= CGRAPH_STATE_CONSTRUCTION
)
1339 for (i
= 0; node
->iterate_referring (i
, ref
); i
++)
1341 if ((ref
->use
== IPA_REF_ALIAS
1342 && referenced_from_vtable_p (dyn_cast
<cgraph_node
*> (ref
->referring
)))
1343 || (ref
->use
== IPA_REF_ADDR
1344 && TREE_CODE (ref
->referring
->decl
) == VAR_DECL
1345 && DECL_VIRTUAL_P (ref
->referring
->decl
)))
1353 /* If TARGET has associated node, record it in the NODES array.
1354 CAN_REFER specify if program can refer to the target directly.
1355 if TARGET is unknown (NULL) or it can not be inserted (for example because
1356 its body was already removed and there is no way to refer to it), clear
1360 maybe_record_node (vec
<cgraph_node
*> &nodes
,
1361 tree target
, hash_set
<tree
> *inserted
,
1365 struct cgraph_node
*target_node
, *alias_target
;
1366 enum availability avail
;
1368 /* cxa_pure_virtual and __builtin_unreachable do not need to be added into
1369 list of targets; the runtime effect of calling them is undefined.
1370 Only "real" virtual methods should be accounted. */
1371 if (target
&& TREE_CODE (TREE_TYPE (target
)) != METHOD_TYPE
)
1376 /* The only case when method of anonymous namespace becomes unreferable
1377 is when we completely optimized it out. */
1380 || !type_in_anonymous_namespace_p (DECL_CONTEXT (target
)))
1388 target_node
= cgraph_node::get (target
);
1390 /* Preffer alias target over aliases, so we do not get confused by
1394 alias_target
= target_node
->ultimate_alias_target (&avail
);
1395 if (target_node
!= alias_target
1396 && avail
>= AVAIL_AVAILABLE
1397 && target_node
->get_availability ())
1398 target_node
= alias_target
;
1401 /* Method can only be called by polymorphic call if any
1402 of vtables refering to it are alive.
1404 While this holds for non-anonymous functions, too, there are
1405 cases where we want to keep them in the list; for example
1406 inline functions with -fno-weak are static, but we still
1407 may devirtualize them when instance comes from other unit.
1408 The same holds for LTO.
1410 Currently we ignore these functions in speculative devirtualization.
1411 ??? Maybe it would make sense to be more aggressive for LTO even
1414 && type_in_anonymous_namespace_p (DECL_CONTEXT (target
))
1416 || !referenced_from_vtable_p (target_node
)))
1418 /* See if TARGET is useful function we can deal with. */
1419 else if (target_node
!= NULL
1420 && (TREE_PUBLIC (target
)
1421 || DECL_EXTERNAL (target
)
1422 || target_node
->definition
)
1423 && target_node
->real_symbol_p ())
1425 gcc_assert (!target_node
->global
.inlined_to
);
1426 gcc_assert (target_node
->real_symbol_p ());
1427 if (!inserted
->add (target
))
1429 cached_polymorphic_call_targets
->add (target_node
);
1430 nodes
.safe_push (target_node
);
1434 && (!type_in_anonymous_namespace_p
1435 (DECL_CONTEXT (target
))
1440 /* See if BINFO's type match OUTER_TYPE. If so, lookup
1441 BINFO of subtype of OTR_TYPE at OFFSET and in that BINFO find
1442 method in vtable and insert method to NODES array
1443 or BASES_TO_CONSIDER if this array is non-NULL.
1444 Otherwise recurse to base BINFOs.
1445 This match what get_binfo_at_offset does, but with offset
1448 TYPE_BINFOS is a stack of BINFOS of types with defined
1449 virtual table seen on way from class type to BINFO.
1451 MATCHED_VTABLES tracks virtual tables we already did lookup
1452 for virtual function in. INSERTED tracks nodes we already
1455 ANONYMOUS is true if BINFO is part of anonymous namespace.
1457 Clear COMPLETEP when we hit unreferable target.
1461 record_target_from_binfo (vec
<cgraph_node
*> &nodes
,
1462 vec
<tree
> *bases_to_consider
,
1465 vec
<tree
> &type_binfos
,
1466 HOST_WIDE_INT otr_token
,
1468 HOST_WIDE_INT offset
,
1469 hash_set
<tree
> *inserted
,
1470 hash_set
<tree
> *matched_vtables
,
1474 tree type
= BINFO_TYPE (binfo
);
1479 if (BINFO_VTABLE (binfo
))
1480 type_binfos
.safe_push (binfo
);
1481 if (types_same_for_odr (type
, outer_type
))
1484 tree type_binfo
= NULL
;
1486 /* Lookup BINFO with virtual table. For normal types it is always last
1488 for (i
= type_binfos
.length () - 1; i
>= 0; i
--)
1489 if (BINFO_OFFSET (type_binfos
[i
]) == BINFO_OFFSET (binfo
))
1491 type_binfo
= type_binfos
[i
];
1494 if (BINFO_VTABLE (binfo
))
1496 /* If this is duplicated BINFO for base shared by virtual inheritance,
1497 we may not have its associated vtable. This is not a problem, since
1498 we will walk it on the other path. */
1501 tree inner_binfo
= get_binfo_at_offset (type_binfo
,
1505 gcc_assert (odr_violation_reported
);
1508 /* For types in anonymous namespace first check if the respective vtable
1509 is alive. If not, we know the type can't be called. */
1510 if (!flag_ltrans
&& anonymous
)
1512 tree vtable
= BINFO_VTABLE (inner_binfo
);
1513 varpool_node
*vnode
;
1515 if (TREE_CODE (vtable
) == POINTER_PLUS_EXPR
)
1516 vtable
= TREE_OPERAND (TREE_OPERAND (vtable
, 0), 0);
1517 vnode
= varpool_node::get (vtable
);
1518 if (!vnode
|| !vnode
->definition
)
1521 gcc_assert (inner_binfo
);
1522 if (bases_to_consider
1523 ? !matched_vtables
->contains (BINFO_VTABLE (inner_binfo
))
1524 : !matched_vtables
->add (BINFO_VTABLE (inner_binfo
)))
1527 tree target
= gimple_get_virt_method_for_binfo (otr_token
,
1530 if (!bases_to_consider
)
1531 maybe_record_node (nodes
, target
, inserted
, can_refer
, completep
);
1532 /* Destructors are never called via construction vtables. */
1533 else if (!target
|| !DECL_CXX_DESTRUCTOR_P (target
))
1534 bases_to_consider
->safe_push (target
);
1540 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
1541 /* Walking bases that have no virtual method is pointless excercise. */
1542 if (polymorphic_type_binfo_p (base_binfo
))
1543 record_target_from_binfo (nodes
, bases_to_consider
, base_binfo
, otr_type
,
1545 otr_token
, outer_type
, offset
, inserted
,
1546 matched_vtables
, anonymous
, completep
);
1547 if (BINFO_VTABLE (binfo
))
1551 /* Lookup virtual methods matching OTR_TYPE (with OFFSET and OTR_TOKEN)
1552 of TYPE, insert them to NODES, recurse into derived nodes.
1553 INSERTED is used to avoid duplicate insertions of methods into NODES.
1554 MATCHED_VTABLES are used to avoid duplicate walking vtables.
1555 Clear COMPLETEP if unreferable target is found.
1557 If CONSIDER_CONSTURCTION is true, record to BASES_TO_CONSDIER
1558 all cases where BASE_SKIPPED is true (because the base is abstract
1562 possible_polymorphic_call_targets_1 (vec
<cgraph_node
*> &nodes
,
1563 hash_set
<tree
> *inserted
,
1564 hash_set
<tree
> *matched_vtables
,
1567 HOST_WIDE_INT otr_token
,
1569 HOST_WIDE_INT offset
,
1571 vec
<tree
> &bases_to_consider
,
1572 bool consider_construction
)
1574 tree binfo
= TYPE_BINFO (type
->type
);
1576 vec
<tree
> type_binfos
= vNULL
;
1577 bool possibly_instantiated
= type_possibly_instantiated_p (type
->type
);
1579 /* We may need to consider types w/o instances because of possible derived
1580 types using their methods either directly or via construction vtables.
1581 We are safe to skip them when all derivations are known, since we will
1583 This is done by recording them to BASES_TO_CONSIDER array. */
1584 if (possibly_instantiated
|| consider_construction
)
1586 record_target_from_binfo (nodes
,
1587 (!possibly_instantiated
1588 && type_all_derivations_known_p (type
->type
))
1589 ? &bases_to_consider
: NULL
,
1590 binfo
, otr_type
, type_binfos
, otr_token
,
1592 inserted
, matched_vtables
,
1593 type
->anonymous_namespace
, completep
);
1595 type_binfos
.release ();
1596 for (i
= 0; i
< type
->derived_types
.length (); i
++)
1597 possible_polymorphic_call_targets_1 (nodes
, inserted
,
1600 type
->derived_types
[i
],
1601 otr_token
, outer_type
, offset
, completep
,
1602 bases_to_consider
, consider_construction
);
1605 /* Cache of queries for polymorphic call targets.
1607 Enumerating all call targets may get expensive when there are many
1608 polymorphic calls in the program, so we memoize all the previous
1609 queries and avoid duplicated work. */
1611 struct polymorphic_call_target_d
1613 HOST_WIDE_INT otr_token
;
1614 ipa_polymorphic_call_context context
;
1616 vec
<cgraph_node
*> targets
;
1617 int speculative_targets
;
1621 /* Polymorphic call target cache helpers. */
1623 struct polymorphic_call_target_hasher
1625 typedef polymorphic_call_target_d value_type
;
1626 typedef polymorphic_call_target_d compare_type
;
1627 static inline hashval_t
hash (const value_type
*);
1628 static inline bool equal (const value_type
*, const compare_type
*);
1629 static inline void remove (value_type
*);
1632 /* Return the computed hashcode for ODR_QUERY. */
1635 polymorphic_call_target_hasher::hash (const value_type
*odr_query
)
1637 inchash::hash
hstate (odr_query
->otr_token
);
1639 hstate
.add_wide_int (odr_query
->type
->id
);
1640 hstate
.merge_hash (TYPE_UID (odr_query
->context
.outer_type
));
1641 hstate
.add_wide_int (odr_query
->context
.offset
);
1643 if (odr_query
->context
.speculative_outer_type
)
1645 hstate
.merge_hash (TYPE_UID (odr_query
->context
.speculative_outer_type
));
1646 hstate
.add_wide_int (odr_query
->context
.speculative_offset
);
1648 hstate
.add_flag (odr_query
->context
.maybe_in_construction
);
1649 hstate
.add_flag (odr_query
->context
.maybe_derived_type
);
1650 hstate
.add_flag (odr_query
->context
.speculative_maybe_derived_type
);
1651 hstate
.commit_flag ();
1652 return hstate
.end ();
1655 /* Compare cache entries T1 and T2. */
1658 polymorphic_call_target_hasher::equal (const value_type
*t1
,
1659 const compare_type
*t2
)
1661 return (t1
->type
== t2
->type
&& t1
->otr_token
== t2
->otr_token
1662 && t1
->context
.offset
== t2
->context
.offset
1663 && t1
->context
.speculative_offset
== t2
->context
.speculative_offset
1664 && t1
->context
.outer_type
== t2
->context
.outer_type
1665 && t1
->context
.speculative_outer_type
== t2
->context
.speculative_outer_type
1666 && t1
->context
.maybe_in_construction
1667 == t2
->context
.maybe_in_construction
1668 && t1
->context
.maybe_derived_type
== t2
->context
.maybe_derived_type
1669 && (t1
->context
.speculative_maybe_derived_type
1670 == t2
->context
.speculative_maybe_derived_type
));
1673 /* Remove entry in polymorphic call target cache hash. */
1676 polymorphic_call_target_hasher::remove (value_type
*v
)
1678 v
->targets
.release ();
1682 /* Polymorphic call target query cache. */
1684 typedef hash_table
<polymorphic_call_target_hasher
>
1685 polymorphic_call_target_hash_type
;
1686 static polymorphic_call_target_hash_type
*polymorphic_call_target_hash
;
1688 /* Destroy polymorphic call target query cache. */
1691 free_polymorphic_call_targets_hash ()
1693 if (cached_polymorphic_call_targets
)
1695 delete polymorphic_call_target_hash
;
1696 polymorphic_call_target_hash
= NULL
;
1697 delete cached_polymorphic_call_targets
;
1698 cached_polymorphic_call_targets
= NULL
;
1702 /* When virtual function is removed, we may need to flush the cache. */
1705 devirt_node_removal_hook (struct cgraph_node
*n
, void *d ATTRIBUTE_UNUSED
)
1707 if (cached_polymorphic_call_targets
1708 && cached_polymorphic_call_targets
->contains (n
))
1709 free_polymorphic_call_targets_hash ();
1712 /* Return true when TYPE contains an polymorphic type and thus is interesting
1713 for devirtualization machinery. */
1716 contains_polymorphic_type_p (const_tree type
)
1718 type
= TYPE_MAIN_VARIANT (type
);
1720 if (RECORD_OR_UNION_TYPE_P (type
))
1722 if (TYPE_BINFO (type
)
1723 && polymorphic_type_binfo_p (TYPE_BINFO (type
)))
1725 for (tree fld
= TYPE_FIELDS (type
); fld
; fld
= DECL_CHAIN (fld
))
1726 if (TREE_CODE (fld
) == FIELD_DECL
1727 && !DECL_ARTIFICIAL (fld
)
1728 && contains_polymorphic_type_p (TREE_TYPE (fld
)))
1732 if (TREE_CODE (type
) == ARRAY_TYPE
)
1733 return contains_polymorphic_type_p (TREE_TYPE (type
));
1737 /* CONTEXT->OUTER_TYPE is a type of memory object where object of EXPECTED_TYPE
1738 is contained at CONTEXT->OFFSET. Walk the memory representation of
1739 CONTEXT->OUTER_TYPE and find the outermost class type that match
1740 EXPECTED_TYPE or contain EXPECTED_TYPE as a base. Update CONTEXT
1743 For example when CONTEXT represents type
1749 and we look for type at offset sizeof(int), we end up with B and offset 0.
1750 If the same is produced by multiple inheritance, we end up with A and offset
1753 If we can not find corresponding class, give up by setting
1754 CONTEXT->OUTER_TYPE to EXPECTED_TYPE and CONTEXT->OFFSET to NULL.
1755 Return true when lookup was sucesful. */
1758 get_class_context (ipa_polymorphic_call_context
*context
,
1761 tree type
= context
->outer_type
;
1762 HOST_WIDE_INT offset
= context
->offset
;
1763 bool speculative
= false;
1764 bool speculation_valid
= false;
1767 if (!context
->outer_type
)
1769 type
= context
->outer_type
= expected_type
;
1770 context
->offset
= offset
= 0;
1772 /* See if speculative type seem to be derrived from outer_type.
1773 Then speculation is valid only if it really is a derivate and derived types
1776 The test does not really look for derivate, but also accepts the case where
1777 outer_type is a field of speculative_outer_type. In this case eiter
1778 MAYBE_DERIVED_TYPE is false and we have full non-speculative information or
1779 the loop bellow will correctly update SPECULATIVE_OUTER_TYPE
1780 and SPECULATIVE_MAYBE_DERIVED_TYPE. */
1781 if (context
->speculative_outer_type
1782 && context
->speculative_offset
>= context
->offset
1783 && contains_type_p (context
->speculative_outer_type
,
1784 context
->offset
- context
->speculative_offset
,
1785 context
->outer_type
))
1786 speculation_valid
= context
->maybe_derived_type
;
1789 context
->speculative_outer_type
= NULL
;
1790 context
->speculative_offset
= 0;
1791 context
->speculative_maybe_derived_type
= false;
1794 /* Find the sub-object the constant actually refers to and mark whether it is
1795 an artificial one (as opposed to a user-defined one).
1797 This loop is performed twice; first time for outer_type and second time
1798 for speculative_outer_type. The second iteration has SPECULATIVE set. */
1801 HOST_WIDE_INT pos
, size
;
1804 /* On a match, just return what we found. */
1805 if (TREE_CODE (type
) == TREE_CODE (expected_type
)
1807 || (TREE_CODE (type
) == RECORD_TYPE
1808 && TYPE_BINFO (type
)
1809 && polymorphic_type_binfo_p (TYPE_BINFO (type
))))
1810 && types_same_for_odr (type
, expected_type
))
1814 gcc_assert (speculation_valid
);
1817 /* If we did not match the offset, just give up on speculation. */
1819 || (types_same_for_odr (context
->speculative_outer_type
,
1820 context
->outer_type
)
1821 && (context
->maybe_derived_type
1822 == context
->speculative_maybe_derived_type
)))
1824 context
->speculative_outer_type
= NULL
;
1825 context
->speculative_offset
= 0;
1831 /* Type can not contain itself on an non-zero offset. In that case
1839 /* If speculation is not valid or we determined type precisely,
1841 if (!speculation_valid
1842 || !context
->maybe_derived_type
)
1844 context
->speculative_outer_type
= NULL
;
1845 context
->speculative_offset
= 0;
1848 /* Otherwise look into speculation now. */
1852 type
= context
->speculative_outer_type
;
1853 offset
= context
->speculative_offset
;
1859 /* Walk fields and find corresponding on at OFFSET. */
1860 if (TREE_CODE (type
) == RECORD_TYPE
)
1862 for (fld
= TYPE_FIELDS (type
); fld
; fld
= DECL_CHAIN (fld
))
1864 if (TREE_CODE (fld
) != FIELD_DECL
)
1867 pos
= int_bit_position (fld
);
1868 size
= tree_to_uhwi (DECL_SIZE (fld
));
1869 if (pos
<= offset
&& (pos
+ size
) > offset
)
1876 type
= TYPE_MAIN_VARIANT (TREE_TYPE (fld
));
1878 /* DECL_ARTIFICIAL represents a basetype. */
1879 if (!DECL_ARTIFICIAL (fld
))
1883 context
->outer_type
= type
;
1884 context
->offset
= offset
;
1885 /* As soon as we se an field containing the type,
1886 we know we are not looking for derivations. */
1887 context
->maybe_derived_type
= false;
1891 context
->speculative_outer_type
= type
;
1892 context
->speculative_offset
= offset
;
1893 context
->speculative_maybe_derived_type
= false;
1897 else if (TREE_CODE (type
) == ARRAY_TYPE
)
1899 tree subtype
= TYPE_MAIN_VARIANT (TREE_TYPE (type
));
1901 /* Give up if we don't know array size. */
1902 if (!tree_fits_shwi_p (TYPE_SIZE (subtype
))
1903 || !tree_to_shwi (TYPE_SIZE (subtype
)) <= 0)
1905 offset
= offset
% tree_to_shwi (TYPE_SIZE (subtype
));
1909 context
->outer_type
= type
;
1910 context
->offset
= offset
;
1911 context
->maybe_derived_type
= false;
1915 context
->speculative_outer_type
= type
;
1916 context
->speculative_offset
= offset
;
1917 context
->speculative_maybe_derived_type
= false;
1920 /* Give up on anything else. */
1925 /* If we failed to find subtype we look for, give up and fall back to the
1926 most generic query. */
1928 context
->speculative_outer_type
= NULL
;
1929 context
->speculative_offset
= 0;
1930 context
->speculative_maybe_derived_type
= false;
1933 context
->outer_type
= expected_type
;
1934 context
->offset
= 0;
1935 context
->maybe_derived_type
= true;
1936 context
->maybe_in_construction
= true;
1937 /* POD can be changed to an instance of a polymorphic type by
1938 placement new. Here we play safe and assume that any
1939 non-polymorphic type is POD. */
1940 if ((TREE_CODE (type
) != RECORD_TYPE
1941 || !TYPE_BINFO (type
)
1942 || !polymorphic_type_binfo_p (TYPE_BINFO (type
)))
1943 && (!TYPE_SIZE (type
)
1944 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
1945 || (offset
+ tree_to_uhwi (TYPE_SIZE (expected_type
)) <=
1946 tree_to_uhwi (TYPE_SIZE (type
)))))
1951 /* Return true if OUTER_TYPE contains OTR_TYPE at OFFSET. */
1954 contains_type_p (tree outer_type
, HOST_WIDE_INT offset
,
1957 ipa_polymorphic_call_context context
= {offset
, 0,
1958 TYPE_MAIN_VARIANT (outer_type
),
1959 NULL
, false, true, false};
1960 return get_class_context (&context
, otr_type
);
1963 /* Lookup base of BINFO that has virtual table VTABLE with OFFSET. */
1966 subbinfo_with_vtable_at_offset (tree binfo
, unsigned HOST_WIDE_INT offset
,
1969 tree v
= BINFO_VTABLE (binfo
);
1972 unsigned HOST_WIDE_INT this_offset
;
1976 if (!vtable_pointer_value_to_vtable (v
, &v
, &this_offset
))
1979 if (offset
== this_offset
1980 && DECL_ASSEMBLER_NAME (v
) == DECL_ASSEMBLER_NAME (vtable
))
1984 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
1985 if (polymorphic_type_binfo_p (base_binfo
))
1987 base_binfo
= subbinfo_with_vtable_at_offset (base_binfo
, offset
, vtable
);
1994 /* T is known constant value of virtual table pointer.
1995 Store virtual table to V and its offset to OFFSET.
1996 Return false if T does not look like virtual table reference. */
1999 vtable_pointer_value_to_vtable (const_tree t
, tree
*v
,
2000 unsigned HOST_WIDE_INT
*offset
)
2002 /* We expect &MEM[(void *)&virtual_table + 16B].
2003 We obtain object's BINFO from the context of the virtual table.
2004 This one contains pointer to virtual table represented via
2005 POINTER_PLUS_EXPR. Verify that this pointer match to what
2006 we propagated through.
2008 In the case of virtual inheritance, the virtual tables may
2009 be nested, i.e. the offset may be different from 16 and we may
2010 need to dive into the type representation. */
2011 if (TREE_CODE (t
) == ADDR_EXPR
2012 && TREE_CODE (TREE_OPERAND (t
, 0)) == MEM_REF
2013 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (t
, 0), 0)) == ADDR_EXPR
2014 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (t
, 0), 1)) == INTEGER_CST
2015 && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t
, 0), 0), 0))
2017 && DECL_VIRTUAL_P (TREE_OPERAND (TREE_OPERAND
2018 (TREE_OPERAND (t
, 0), 0), 0)))
2020 *v
= TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t
, 0), 0), 0);
2021 *offset
= tree_to_uhwi (TREE_OPERAND (TREE_OPERAND (t
, 0), 1));
2025 /* Alternative representation, used by C++ frontend is POINTER_PLUS_EXPR.
2026 We need to handle it when T comes from static variable initializer or
2028 if (TREE_CODE (t
) == POINTER_PLUS_EXPR
)
2030 *offset
= tree_to_uhwi (TREE_OPERAND (t
, 1));
2031 t
= TREE_OPERAND (t
, 0);
2036 if (TREE_CODE (t
) != ADDR_EXPR
)
2038 *v
= TREE_OPERAND (t
, 0);
2042 /* T is known constant value of virtual table pointer. Return BINFO of the
2046 vtable_pointer_value_to_binfo (const_tree t
)
2049 unsigned HOST_WIDE_INT offset
;
2051 if (!vtable_pointer_value_to_vtable (t
, &vtable
, &offset
))
2054 /* FIXME: for stores of construction vtables we return NULL,
2055 because we do not have BINFO for those. Eventually we should fix
2056 our representation to allow this case to be handled, too.
2057 In the case we see store of BINFO we however may assume
2058 that standard folding will be ale to cope with it. */
2059 return subbinfo_with_vtable_at_offset (TYPE_BINFO (DECL_CONTEXT (vtable
)),
2063 /* We know that the instance is stored in variable or parameter
2064 (not dynamically allocated) and we want to disprove the fact
2065 that it may be in construction at invocation of CALL.
2067 For the variable to be in construction we actually need to
2068 be in constructor of corresponding global variable or
2069 the inline stack of CALL must contain the constructor.
2070 Check this condition. This check works safely only before
2071 IPA passes, because inline stacks may become out of date
2075 decl_maybe_in_construction_p (tree base
, tree outer_type
,
2076 gimple call
, tree function
)
2078 outer_type
= TYPE_MAIN_VARIANT (outer_type
);
2079 gcc_assert (DECL_P (base
));
2081 /* After inlining the code unification optimizations may invalidate
2082 inline stacks. Also we need to give up on global variables after
2083 IPA, because addresses of these may have been propagated to their
2085 if (DECL_STRUCT_FUNCTION (function
)->after_inlining
)
2088 /* Pure functions can not do any changes on the dynamic type;
2089 that require writting to memory. */
2090 if (!auto_var_in_fn_p (base
, function
)
2091 && flags_from_decl_or_type (function
) & (ECF_PURE
| ECF_CONST
))
2094 for (tree block
= gimple_block (call
); block
&& TREE_CODE (block
) == BLOCK
;
2095 block
= BLOCK_SUPERCONTEXT (block
))
2096 if (BLOCK_ABSTRACT_ORIGIN (block
)
2097 && TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block
)) == FUNCTION_DECL
)
2099 tree fn
= BLOCK_ABSTRACT_ORIGIN (block
);
2101 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
2102 || (!DECL_CXX_CONSTRUCTOR_P (fn
)
2103 || !DECL_CXX_DESTRUCTOR_P (fn
)))
2105 /* Watch for clones where we constant propagated the first
2106 argument (pointer to the instance). */
2107 fn
= DECL_ABSTRACT_ORIGIN (fn
);
2109 || !is_global_var (base
)
2110 || TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
2111 || (!DECL_CXX_CONSTRUCTOR_P (fn
)
2112 || !DECL_CXX_DESTRUCTOR_P (fn
)))
2115 if (flags_from_decl_or_type (fn
) & (ECF_PURE
| ECF_CONST
))
2118 /* FIXME: this can go away once we have ODR types equivalency on
2120 if (in_lto_p
&& !polymorphic_type_binfo_p (TYPE_BINFO (outer_type
)))
2122 tree type
= TYPE_MAIN_VARIANT (method_class_type (TREE_TYPE (fn
)));
2123 if (types_same_for_odr (type
, outer_type
))
2127 if (TREE_CODE (base
) == VAR_DECL
2128 && is_global_var (base
))
2130 if (TREE_CODE (TREE_TYPE (function
)) != METHOD_TYPE
2131 || (!DECL_CXX_CONSTRUCTOR_P (function
)
2132 || !DECL_CXX_DESTRUCTOR_P (function
)))
2134 if (!DECL_ABSTRACT_ORIGIN (function
))
2136 /* Watch for clones where we constant propagated the first
2137 argument (pointer to the instance). */
2138 function
= DECL_ABSTRACT_ORIGIN (function
);
2140 || TREE_CODE (TREE_TYPE (function
)) != METHOD_TYPE
2141 || (!DECL_CXX_CONSTRUCTOR_P (function
)
2142 || !DECL_CXX_DESTRUCTOR_P (function
)))
2145 /* FIXME: this can go away once we have ODR types equivalency on
2147 if (in_lto_p
&& !polymorphic_type_binfo_p (TYPE_BINFO (outer_type
)))
2149 tree type
= TYPE_MAIN_VARIANT (method_class_type (TREE_TYPE (function
)));
2150 if (types_same_for_odr (type
, outer_type
))
2156 /* Proudce polymorphic call context for call method of instance
2157 that is located within BASE (that is assumed to be a decl) at OFFSET. */
2160 get_polymorphic_call_info_for_decl (ipa_polymorphic_call_context
*context
,
2161 tree base
, HOST_WIDE_INT offset
)
2163 gcc_assert (DECL_P (base
));
2165 context
->outer_type
= TYPE_MAIN_VARIANT (TREE_TYPE (base
));
2166 context
->offset
= offset
;
2167 context
->speculative_outer_type
= NULL
;
2168 context
->speculative_offset
= 0;
2169 context
->speculative_maybe_derived_type
= true;
2170 /* Make very conservative assumption that all objects
2171 may be in construction.
2172 TODO: ipa-prop already contains code to tell better.
2174 context
->maybe_in_construction
= true;
2175 context
->maybe_derived_type
= false;
2178 /* CST is an invariant (address of decl), try to get meaningful
2179 polymorphic call context for polymorphic call of method
2180 if instance of OTR_TYPE that is located at OFFSET of this invariant.
2181 Return FALSE if nothing meaningful can be found. */
2184 get_polymorphic_call_info_from_invariant (ipa_polymorphic_call_context
*context
,
2187 HOST_WIDE_INT offset
)
2189 HOST_WIDE_INT offset2
, size
, max_size
;
2192 if (TREE_CODE (cst
) != ADDR_EXPR
)
2195 cst
= TREE_OPERAND (cst
, 0);
2196 base
= get_ref_base_and_extent (cst
, &offset2
, &size
, &max_size
);
2197 if (!DECL_P (base
) || max_size
== -1 || max_size
!= size
)
2200 /* Only type inconsistent programs can have otr_type that is
2201 not part of outer type. */
2202 if (!contains_type_p (TREE_TYPE (base
), offset
, otr_type
))
2205 get_polymorphic_call_info_for_decl (context
, base
, offset
);
2209 /* See if OP is SSA name initialized as a copy or by single assignment.
2210 If so, walk the SSA graph up. */
2213 walk_ssa_copies (tree op
)
2216 while (TREE_CODE (op
) == SSA_NAME
2217 && !SSA_NAME_IS_DEFAULT_DEF (op
)
2218 && SSA_NAME_DEF_STMT (op
)
2219 && gimple_assign_single_p (SSA_NAME_DEF_STMT (op
)))
2221 if (gimple_assign_load_p (SSA_NAME_DEF_STMT (op
)))
2223 op
= gimple_assign_rhs1 (SSA_NAME_DEF_STMT (op
));
2229 /* Given REF call in FNDECL, determine class of the polymorphic
2230 call (OTR_TYPE), its token (OTR_TOKEN) and CONTEXT.
2231 CALL is optional argument giving the actual statement (usually call) where
2232 the context is used.
2233 Return pointer to object described by the context */
2236 get_polymorphic_call_info (tree fndecl
,
2239 HOST_WIDE_INT
*otr_token
,
2240 ipa_polymorphic_call_context
*context
,
2244 *otr_type
= obj_type_ref_class (ref
);
2245 *otr_token
= tree_to_uhwi (OBJ_TYPE_REF_TOKEN (ref
));
2247 /* Set up basic info in case we find nothing interesting in the analysis. */
2248 context
->speculative_outer_type
= NULL
;
2249 context
->speculative_offset
= 0;
2250 context
->speculative_maybe_derived_type
= true;
2251 context
->outer_type
= TYPE_MAIN_VARIANT (*otr_type
);
2252 context
->offset
= 0;
2253 base_pointer
= OBJ_TYPE_REF_OBJECT (ref
);
2254 context
->maybe_derived_type
= true;
2255 context
->maybe_in_construction
= true;
2257 /* Walk SSA for outer object. */
2260 base_pointer
= walk_ssa_copies (base_pointer
);
2261 if (TREE_CODE (base_pointer
) == ADDR_EXPR
)
2263 HOST_WIDE_INT size
, max_size
;
2264 HOST_WIDE_INT offset2
;
2265 tree base
= get_ref_base_and_extent (TREE_OPERAND (base_pointer
, 0),
2266 &offset2
, &size
, &max_size
);
2268 /* If this is a varying address, punt. */
2269 if ((TREE_CODE (base
) == MEM_REF
|| DECL_P (base
))
2271 && max_size
== size
)
2273 /* We found dereference of a pointer. Type of the pointer
2274 and MEM_REF is meaningless, but we can look futher. */
2275 if (TREE_CODE (base
) == MEM_REF
)
2277 base_pointer
= TREE_OPERAND (base
, 0);
2279 += offset2
+ mem_ref_offset (base
).to_short_addr () * BITS_PER_UNIT
;
2280 context
->outer_type
= NULL
;
2282 /* We found base object. In this case the outer_type
2284 else if (DECL_P (base
))
2286 gcc_assert (!POINTER_TYPE_P (TREE_TYPE (base
)));
2288 /* Only type inconsistent programs can have otr_type that is
2289 not part of outer type. */
2290 if (!contains_type_p (TREE_TYPE (base
),
2291 context
->offset
+ offset2
, *otr_type
))
2293 /* Use OTR_TOKEN = INT_MAX as a marker of probably type inconsistent
2294 code sequences; we arrange the calls to be builtin_unreachable
2296 *otr_token
= INT_MAX
;
2297 return base_pointer
;
2299 get_polymorphic_call_info_for_decl (context
, base
,
2300 context
->offset
+ offset2
);
2301 if (context
->maybe_in_construction
&& call
)
2302 context
->maybe_in_construction
2303 = decl_maybe_in_construction_p (base
,
2304 context
->outer_type
,
2306 current_function_decl
);
2307 return base_pointer
;
2315 else if (TREE_CODE (base_pointer
) == POINTER_PLUS_EXPR
2316 && tree_fits_uhwi_p (TREE_OPERAND (base_pointer
, 1)))
2318 context
->offset
+= tree_to_shwi (TREE_OPERAND (base_pointer
, 1))
2320 base_pointer
= TREE_OPERAND (base_pointer
, 0);
2327 /* Try to determine type of the outer object. */
2328 if (TREE_CODE (base_pointer
) == SSA_NAME
2329 && SSA_NAME_IS_DEFAULT_DEF (base_pointer
)
2330 && TREE_CODE (SSA_NAME_VAR (base_pointer
)) == PARM_DECL
)
2332 /* See if parameter is THIS pointer of a method. */
2333 if (TREE_CODE (TREE_TYPE (fndecl
)) == METHOD_TYPE
2334 && SSA_NAME_VAR (base_pointer
) == DECL_ARGUMENTS (fndecl
))
2337 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (base_pointer
)));
2338 gcc_assert (TREE_CODE (context
->outer_type
) == RECORD_TYPE
);
2340 /* Dynamic casting has possibly upcasted the type
2341 in the hiearchy. In this case outer type is less
2342 informative than inner type and we should forget
2344 if (!contains_type_p (context
->outer_type
, context
->offset
,
2347 context
->outer_type
= NULL
;
2348 return base_pointer
;
2351 /* If the function is constructor or destructor, then
2352 the type is possibly in construction, but we know
2353 it is not derived type. */
2354 if (DECL_CXX_CONSTRUCTOR_P (fndecl
)
2355 || DECL_CXX_DESTRUCTOR_P (fndecl
))
2357 context
->maybe_in_construction
= true;
2358 context
->maybe_derived_type
= false;
2362 context
->maybe_derived_type
= true;
2363 context
->maybe_in_construction
= false;
2365 return base_pointer
;
2367 /* Non-PODs passed by value are really passed by invisible
2368 reference. In this case we also know the type of the
2370 if (DECL_BY_REFERENCE (SSA_NAME_VAR (base_pointer
)))
2373 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (base_pointer
)));
2374 gcc_assert (!POINTER_TYPE_P (context
->outer_type
));
2375 /* Only type inconsistent programs can have otr_type that is
2376 not part of outer type. */
2377 if (!contains_type_p (context
->outer_type
, context
->offset
,
2380 /* Use OTR_TOKEN = INT_MAX as a marker of probably type inconsistent
2381 code sequences; we arrange the calls to be builtin_unreachable
2383 *otr_token
= INT_MAX
;
2384 return base_pointer
;
2386 context
->maybe_derived_type
= false;
2387 context
->maybe_in_construction
= false;
2388 return base_pointer
;
2392 tree base_type
= TREE_TYPE (base_pointer
);
2394 if (TREE_CODE (base_pointer
) == SSA_NAME
2395 && SSA_NAME_IS_DEFAULT_DEF (base_pointer
)
2396 && TREE_CODE (SSA_NAME_VAR (base_pointer
)) != PARM_DECL
)
2398 /* Use OTR_TOKEN = INT_MAX as a marker of probably type inconsistent
2399 code sequences; we arrange the calls to be builtin_unreachable
2401 *otr_token
= INT_MAX
;
2402 return base_pointer
;
2404 if (TREE_CODE (base_pointer
) == SSA_NAME
2405 && SSA_NAME_DEF_STMT (base_pointer
)
2406 && gimple_assign_single_p (SSA_NAME_DEF_STMT (base_pointer
)))
2407 base_type
= TREE_TYPE (gimple_assign_rhs1
2408 (SSA_NAME_DEF_STMT (base_pointer
)));
2410 if (POINTER_TYPE_P (base_type
)
2411 && contains_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (base_type
)),
2415 context
->speculative_outer_type
= TYPE_MAIN_VARIANT
2416 (TREE_TYPE (base_type
));
2417 context
->speculative_offset
= context
->offset
;
2418 context
->speculative_maybe_derived_type
= true;
2420 /* TODO: There are multiple ways to derive a type. For instance
2421 if BASE_POINTER is passed to an constructor call prior our refernece.
2422 We do not make this type of flow sensitive analysis yet. */
2423 return base_pointer
;
2426 /* Walk bases of OUTER_TYPE that contain OTR_TYPE at OFFSET.
2427 Lookup their respecitve virtual methods for OTR_TOKEN and OTR_TYPE
2428 and insert them to NODES.
2430 MATCHED_VTABLES and INSERTED is used to avoid duplicated work. */
2433 record_targets_from_bases (tree otr_type
,
2434 HOST_WIDE_INT otr_token
,
2436 HOST_WIDE_INT offset
,
2437 vec
<cgraph_node
*> &nodes
,
2438 hash_set
<tree
> *inserted
,
2439 hash_set
<tree
> *matched_vtables
,
2444 HOST_WIDE_INT pos
, size
;
2448 if (types_same_for_odr (outer_type
, otr_type
))
2451 for (fld
= TYPE_FIELDS (outer_type
); fld
; fld
= DECL_CHAIN (fld
))
2453 if (TREE_CODE (fld
) != FIELD_DECL
)
2456 pos
= int_bit_position (fld
);
2457 size
= tree_to_shwi (DECL_SIZE (fld
));
2458 if (pos
<= offset
&& (pos
+ size
) > offset
2459 /* Do not get confused by zero sized bases. */
2460 && polymorphic_type_binfo_p (TYPE_BINFO (TREE_TYPE (fld
))))
2463 /* Within a class type we should always find correcponding fields. */
2464 gcc_assert (fld
&& TREE_CODE (TREE_TYPE (fld
)) == RECORD_TYPE
);
2466 /* Nonbasetypes should have been stripped by outer_class_type. */
2467 gcc_assert (DECL_ARTIFICIAL (fld
));
2469 outer_type
= TREE_TYPE (fld
);
2472 base_binfo
= get_binfo_at_offset (TYPE_BINFO (outer_type
),
2476 gcc_assert (odr_violation_reported
);
2479 gcc_assert (base_binfo
);
2480 if (!matched_vtables
->add (BINFO_VTABLE (base_binfo
)))
2483 tree target
= gimple_get_virt_method_for_binfo (otr_token
,
2486 if (!target
|| ! DECL_CXX_DESTRUCTOR_P (target
))
2487 maybe_record_node (nodes
, target
, inserted
, can_refer
, completep
);
2488 matched_vtables
->add (BINFO_VTABLE (base_binfo
));
2493 /* When virtual table is removed, we may need to flush the cache. */
2496 devirt_variable_node_removal_hook (varpool_node
*n
,
2497 void *d ATTRIBUTE_UNUSED
)
2499 if (cached_polymorphic_call_targets
2500 && DECL_VIRTUAL_P (n
->decl
)
2501 && type_in_anonymous_namespace_p (DECL_CONTEXT (n
->decl
)))
2502 free_polymorphic_call_targets_hash ();
2505 /* Return vector containing possible targets of polymorphic call of type
2506 OTR_TYPE caling method OTR_TOKEN within type of OTR_OUTER_TYPE and OFFSET.
2507 If INCLUDE_BASES is true, walk also base types of OUTER_TYPES containig
2508 OTR_TYPE and include their virtual method. This is useful for types
2509 possibly in construction or destruction where the virtual table may
2510 temporarily change to one of base types. INCLUDE_DERIVER_TYPES make
2511 us to walk the inheritance graph for all derivations.
2513 OTR_TOKEN == INT_MAX is used to mark calls that are provably
2514 undefined and should be redirected to unreachable.
2516 If COMPLETEP is non-NULL, store true if the list is complete.
2517 CACHE_TOKEN (if non-NULL) will get stored to an unique ID of entry
2518 in the target cache. If user needs to visit every target list
2519 just once, it can memoize them.
2521 SPECULATION_TARGETS specify number of targets that are speculatively
2522 likely. These include targets specified by the speculative part
2523 of polymoprhic call context and also exclude all targets for classes
2526 Returned vector is placed into cache. It is NOT caller's responsibility
2527 to free it. The vector can be freed on cgraph_remove_node call if
2528 the particular node is a virtual function present in the cache. */
2531 possible_polymorphic_call_targets (tree otr_type
,
2532 HOST_WIDE_INT otr_token
,
2533 ipa_polymorphic_call_context context
,
2536 int *speculative_targetsp
)
2538 static struct cgraph_node_hook_list
*node_removal_hook_holder
;
2539 vec
<cgraph_node
*> nodes
= vNULL
;
2540 vec
<tree
> bases_to_consider
= vNULL
;
2541 odr_type type
, outer_type
;
2542 polymorphic_call_target_d key
;
2543 polymorphic_call_target_d
**slot
;
2548 bool skipped
= false;
2550 otr_type
= TYPE_MAIN_VARIANT (otr_type
);
2552 /* If ODR is not initialized, return empty incomplete list. */
2558 *cache_token
= NULL
;
2559 if (speculative_targetsp
)
2560 *speculative_targetsp
= 0;
2564 /* If we hit type inconsistency, just return empty list of targets. */
2565 if (otr_token
== INT_MAX
)
2570 *cache_token
= NULL
;
2571 if (speculative_targetsp
)
2572 *speculative_targetsp
= 0;
2576 type
= get_odr_type (otr_type
, true);
2578 /* Recording type variants would wast results cache. */
2579 gcc_assert (!context
.outer_type
2580 || TYPE_MAIN_VARIANT (context
.outer_type
) == context
.outer_type
);
2582 /* Lookup the outer class type we want to walk. */
2583 if ((context
.outer_type
|| context
.speculative_outer_type
)
2584 && !get_class_context (&context
, otr_type
))
2589 *cache_token
= NULL
;
2590 if (speculative_targetsp
)
2591 *speculative_targetsp
= 0;
2595 /* Check that get_class_context kept the main variant. */
2596 gcc_assert (!context
.outer_type
2597 || TYPE_MAIN_VARIANT (context
.outer_type
) == context
.outer_type
);
2599 /* We canonicalize our query, so we do not need extra hashtable entries. */
2601 /* Without outer type, we have no use for offset. Just do the
2602 basic search from innter type */
2603 if (!context
.outer_type
)
2605 context
.outer_type
= otr_type
;
2608 /* We need to update our hiearchy if the type does not exist. */
2609 outer_type
= get_odr_type (context
.outer_type
, true);
2610 /* If the type is complete, there are no derivations. */
2611 if (TYPE_FINAL_P (outer_type
->type
))
2612 context
.maybe_derived_type
= false;
2614 /* Initialize query cache. */
2615 if (!cached_polymorphic_call_targets
)
2617 cached_polymorphic_call_targets
= new hash_set
<cgraph_node
*>;
2618 polymorphic_call_target_hash
2619 = new polymorphic_call_target_hash_type (23);
2620 if (!node_removal_hook_holder
)
2622 node_removal_hook_holder
=
2623 cgraph_add_node_removal_hook (&devirt_node_removal_hook
, NULL
);
2624 varpool_add_node_removal_hook (&devirt_variable_node_removal_hook
,
2629 /* Lookup cached answer. */
2631 key
.otr_token
= otr_token
;
2632 key
.context
= context
;
2633 slot
= polymorphic_call_target_hash
->find_slot (&key
, INSERT
);
2635 *cache_token
= (void *)*slot
;
2639 *completep
= (*slot
)->complete
;
2640 if (speculative_targetsp
)
2641 *speculative_targetsp
= (*slot
)->speculative_targets
;
2642 return (*slot
)->targets
;
2647 /* Do actual search. */
2648 timevar_push (TV_IPA_VIRTUAL_CALL
);
2649 *slot
= XCNEW (polymorphic_call_target_d
);
2651 *cache_token
= (void *)*slot
;
2652 (*slot
)->type
= type
;
2653 (*slot
)->otr_token
= otr_token
;
2654 (*slot
)->context
= context
;
2655 (*slot
)->speculative_targets
= 0;
2657 hash_set
<tree
> inserted
;
2658 hash_set
<tree
> matched_vtables
;
2660 if (context
.speculative_outer_type
)
2662 odr_type speculative_outer_type
;
2663 speculative_outer_type
= get_odr_type (context
.speculative_outer_type
, true);
2664 if (TYPE_FINAL_P (speculative_outer_type
->type
))
2665 context
.speculative_maybe_derived_type
= false;
2666 binfo
= get_binfo_at_offset (TYPE_BINFO (speculative_outer_type
->type
),
2667 context
.speculative_offset
, otr_type
);
2669 target
= gimple_get_virt_method_for_binfo (otr_token
, binfo
,
2676 /* In the case we get complete method, we don't need
2677 to walk derivations. */
2678 if (DECL_FINAL_P (target
))
2679 context
.speculative_maybe_derived_type
= false;
2681 if (type_possibly_instantiated_p (speculative_outer_type
->type
))
2682 maybe_record_node (nodes
, target
, &inserted
, can_refer
, &complete
);
2684 matched_vtables
.add (BINFO_VTABLE (binfo
));
2685 /* Next walk recursively all derived types. */
2686 if (context
.speculative_maybe_derived_type
)
2688 /* For anonymous namespace types we can attempt to build full type.
2689 All derivations must be in this unit (unless we see partial unit). */
2690 if (!type
->all_derivations_known
)
2692 for (i
= 0; i
< speculative_outer_type
->derived_types
.length(); i
++)
2693 possible_polymorphic_call_targets_1 (nodes
, &inserted
,
2696 speculative_outer_type
->derived_types
[i
],
2697 otr_token
, speculative_outer_type
->type
,
2698 context
.speculative_offset
, &complete
,
2702 /* Finally walk bases, if asked to. */
2703 (*slot
)->speculative_targets
= nodes
.length();
2706 /* First see virtual method of type itself. */
2707 binfo
= get_binfo_at_offset (TYPE_BINFO (outer_type
->type
),
2708 context
.offset
, otr_type
);
2710 target
= gimple_get_virt_method_for_binfo (otr_token
, binfo
,
2714 gcc_assert (odr_violation_reported
);
2718 /* Destructors are never called through construction virtual tables,
2719 because the type is always known. */
2720 if (target
&& DECL_CXX_DESTRUCTOR_P (target
))
2721 context
.maybe_in_construction
= false;
2725 /* In the case we get complete method, we don't need
2726 to walk derivations. */
2727 if (DECL_FINAL_P (target
))
2728 context
.maybe_derived_type
= false;
2731 /* If OUTER_TYPE is abstract, we know we are not seeing its instance. */
2732 if (type_possibly_instantiated_p (outer_type
->type
))
2733 maybe_record_node (nodes
, target
, &inserted
, can_refer
, &complete
);
2737 gcc_assert (in_lto_p
|| context
.maybe_derived_type
);
2741 matched_vtables
.add (BINFO_VTABLE (binfo
));
2743 /* Next walk recursively all derived types. */
2744 if (context
.maybe_derived_type
)
2746 /* For anonymous namespace types we can attempt to build full type.
2747 All derivations must be in this unit (unless we see partial unit). */
2748 if (!type
->all_derivations_known
)
2750 for (i
= 0; i
< outer_type
->derived_types
.length(); i
++)
2751 possible_polymorphic_call_targets_1 (nodes
, &inserted
,
2754 outer_type
->derived_types
[i
],
2755 otr_token
, outer_type
->type
,
2756 context
.offset
, &complete
,
2758 context
.maybe_in_construction
);
2761 /* Finally walk bases, if asked to. */
2762 if (!(*slot
)->speculative_targets
)
2763 (*slot
)->speculative_targets
= nodes
.length();
2765 /* Destructors are never called through construction virtual tables,
2766 because the type is always known. One of entries may be cxa_pure_virtual
2767 so look to at least two of them. */
2768 if (context
.maybe_in_construction
)
2769 for (i
=0 ; i
< MIN (nodes
.length (), 2); i
++)
2770 if (DECL_CXX_DESTRUCTOR_P (nodes
[i
]->decl
))
2771 context
.maybe_in_construction
= false;
2772 if (context
.maybe_in_construction
)
2774 if (type
!= outer_type
2776 || (context
.maybe_derived_type
2777 && !type_all_derivations_known_p (outer_type
->type
))))
2778 record_targets_from_bases (otr_type
, otr_token
, outer_type
->type
,
2779 context
.offset
, nodes
, &inserted
,
2780 &matched_vtables
, &complete
);
2782 maybe_record_node (nodes
, target
, &inserted
, can_refer
, &complete
);
2783 for (i
= 0; i
< bases_to_consider
.length(); i
++)
2784 maybe_record_node (nodes
, bases_to_consider
[i
], &inserted
, can_refer
, &complete
);
2786 bases_to_consider
.release();
2788 (*slot
)->targets
= nodes
;
2789 (*slot
)->complete
= complete
;
2791 *completep
= complete
;
2792 if (speculative_targetsp
)
2793 *speculative_targetsp
= (*slot
)->speculative_targets
;
2795 timevar_pop (TV_IPA_VIRTUAL_CALL
);
2799 /* Dump all possible targets of a polymorphic call. */
2802 dump_possible_polymorphic_call_targets (FILE *f
,
2804 HOST_WIDE_INT otr_token
,
2805 const ipa_polymorphic_call_context
&ctx
)
2807 vec
<cgraph_node
*> targets
;
2809 odr_type type
= get_odr_type (TYPE_MAIN_VARIANT (otr_type
), false);
2815 targets
= possible_polymorphic_call_targets (otr_type
, otr_token
,
2817 &final
, NULL
, &speculative
);
2818 fprintf (f
, " Targets of polymorphic call of type %i:", type
->id
);
2819 print_generic_expr (f
, type
->type
, TDF_SLIM
);
2820 fprintf (f
, " token %i\n", (int)otr_token
);
2821 if (ctx
.outer_type
|| ctx
.offset
)
2823 fprintf (f
, " Contained in type:");
2824 print_generic_expr (f
, ctx
.outer_type
, TDF_SLIM
);
2825 fprintf (f
, " at offset "HOST_WIDE_INT_PRINT_DEC
"\n",
2828 if (ctx
.speculative_outer_type
)
2830 fprintf (f
, " Speculatively contained in type:");
2831 print_generic_expr (f
, ctx
.speculative_outer_type
, TDF_SLIM
);
2832 fprintf (f
, " at offset "HOST_WIDE_INT_PRINT_DEC
"\n",
2833 ctx
.speculative_offset
);
2836 fprintf (f
, " %s%s%s%s\n ",
2837 final
? "This is a complete list." :
2838 "This is partial list; extra targets may be defined in other units.",
2839 ctx
.maybe_in_construction
? " (base types included)" : "",
2840 ctx
.maybe_derived_type
? " (derived types included)" : "",
2841 ctx
.speculative_maybe_derived_type
? " (speculative derived types included)" : "");
2842 for (i
= 0; i
< targets
.length (); i
++)
2845 if (i
== (unsigned)speculative
)
2846 fprintf (f
, "\n Targets that are not likely:\n"
2849 name
= cplus_demangle_v3 (targets
[i
]->asm_name (), 0);
2850 fprintf (f
, " %s/%i", name
? name
: targets
[i
]->name (), targets
[i
]->order
);
2853 if (!targets
[i
]->definition
)
2854 fprintf (f
, " (no definition%s)",
2855 DECL_DECLARED_INLINE_P (targets
[i
]->decl
)
2858 fprintf (f
, "\n\n");
2862 /* Return true if N can be possibly target of a polymorphic call of
2863 OTR_TYPE/OTR_TOKEN. */
2866 possible_polymorphic_call_target_p (tree otr_type
,
2867 HOST_WIDE_INT otr_token
,
2868 const ipa_polymorphic_call_context
&ctx
,
2869 struct cgraph_node
*n
)
2871 vec
<cgraph_node
*> targets
;
2873 enum built_in_function fcode
;
2876 if (TREE_CODE (TREE_TYPE (n
->decl
)) == FUNCTION_TYPE
2877 && ((fcode
= DECL_FUNCTION_CODE (n
->decl
))
2878 == BUILT_IN_UNREACHABLE
2879 || fcode
== BUILT_IN_TRAP
))
2884 targets
= possible_polymorphic_call_targets (otr_type
, otr_token
, ctx
, &final
);
2885 for (i
= 0; i
< targets
.length (); i
++)
2886 if (n
->semantically_equivalent_p (targets
[i
]))
2889 /* At a moment we allow middle end to dig out new external declarations
2890 as a targets of polymorphic calls. */
2891 if (!final
&& !n
->definition
)
2897 /* After callgraph construction new external nodes may appear.
2898 Add them into the graph. */
2901 update_type_inheritance_graph (void)
2903 struct cgraph_node
*n
;
2907 free_polymorphic_call_targets_hash ();
2908 timevar_push (TV_IPA_INHERITANCE
);
2909 /* We reconstruct the graph starting from types of all methods seen in the
2911 FOR_EACH_FUNCTION (n
)
2912 if (DECL_VIRTUAL_P (n
->decl
)
2914 && n
->real_symbol_p ())
2915 get_odr_type (method_class_type (TYPE_MAIN_VARIANT (TREE_TYPE (n
->decl
))),
2917 timevar_pop (TV_IPA_INHERITANCE
);
2921 /* Return true if N looks like likely target of a polymorphic call.
2922 Rule out cxa_pure_virtual, noreturns, function declared cold and
2923 other obvious cases. */
2926 likely_target_p (struct cgraph_node
*n
)
2929 /* cxa_pure_virtual and similar things are not likely. */
2930 if (TREE_CODE (TREE_TYPE (n
->decl
)) != METHOD_TYPE
)
2932 flags
= flags_from_decl_or_type (n
->decl
);
2933 if (flags
& ECF_NORETURN
)
2935 if (lookup_attribute ("cold",
2936 DECL_ATTRIBUTES (n
->decl
)))
2938 if (n
->frequency
< NODE_FREQUENCY_NORMAL
)
2940 /* If there are no virtual tables refering the target alive,
2941 the only way the target can be called is an instance comming from other
2942 compilation unit; speculative devirtualization is build around an
2943 assumption that won't happen. */
2944 if (!referenced_from_vtable_p (n
))
2949 /* The ipa-devirt pass.
2950 When polymorphic call has only one likely target in the unit,
2951 turn it into speculative call. */
2956 struct cgraph_node
*n
;
2957 hash_set
<void *> bad_call_targets
;
2958 struct cgraph_edge
*e
;
2960 int npolymorphic
= 0, nspeculated
= 0, nconverted
= 0, ncold
= 0;
2961 int nmultiple
= 0, noverwritable
= 0, ndevirtualized
= 0, nnotdefined
= 0;
2962 int nwrong
= 0, nok
= 0, nexternal
= 0, nartificial
= 0;
2964 FOR_EACH_DEFINED_FUNCTION (n
)
2966 bool update
= false;
2967 if (dump_file
&& n
->indirect_calls
)
2968 fprintf (dump_file
, "\n\nProcesing function %s/%i\n",
2969 n
->name (), n
->order
);
2970 for (e
= n
->indirect_calls
; e
; e
= e
->next_callee
)
2971 if (e
->indirect_info
->polymorphic
)
2973 struct cgraph_node
*likely_target
= NULL
;
2976 int speculative_targets
;
2977 vec
<cgraph_node
*>targets
2978 = possible_polymorphic_call_targets
2979 (e
, &final
, &cache_token
, &speculative_targets
);
2983 dump_possible_polymorphic_call_targets
2988 if (!cgraph_maybe_hot_edge_p (e
))
2991 fprintf (dump_file
, "Call is cold\n\n");
2998 fprintf (dump_file
, "Call is aready speculated\n\n");
3001 /* When dumping see if we agree with speculation. */
3005 if (bad_call_targets
.contains (cache_token
))
3008 fprintf (dump_file
, "Target list is known to be useless\n\n");
3012 for (i
= 0; i
< targets
.length (); i
++)
3013 if (likely_target_p (targets
[i
]))
3017 if (i
< (unsigned) speculative_targets
)
3019 likely_target
= NULL
;
3021 fprintf (dump_file
, "More than one likely target\n\n");
3026 likely_target
= targets
[i
];
3030 bad_call_targets
.add (cache_token
);
3033 /* This is reached only when dumping; check if we agree or disagree
3034 with the speculation. */
3037 struct cgraph_edge
*e2
;
3038 struct ipa_ref
*ref
;
3039 cgraph_speculative_call_info (e
, e2
, e
, ref
);
3040 if (e2
->callee
->ultimate_alias_target ()
3041 == likely_target
->ultimate_alias_target ())
3043 fprintf (dump_file
, "We agree with speculation\n\n");
3048 fprintf (dump_file
, "We disagree with speculation\n\n");
3053 if (!likely_target
->definition
)
3056 fprintf (dump_file
, "Target is not an definition\n\n");
3060 /* Do not introduce new references to external symbols. While we
3061 can handle these just well, it is common for programs to
3062 incorrectly with headers defining methods they are linked
3064 if (DECL_EXTERNAL (likely_target
->decl
))
3067 fprintf (dump_file
, "Target is external\n\n");
3071 /* Don't use an implicitly-declared destructor (c++/58678). */
3072 struct cgraph_node
*non_thunk_target
3073 = likely_target
->function_symbol ();
3074 if (DECL_ARTIFICIAL (non_thunk_target
->decl
)
3075 && DECL_COMDAT (non_thunk_target
->decl
))
3078 fprintf (dump_file
, "Target is artificial\n\n");
3082 if (likely_target
->get_availability () <= AVAIL_INTERPOSABLE
3083 && likely_target
->can_be_discarded_p ())
3086 fprintf (dump_file
, "Target is overwritable\n\n");
3090 else if (dbg_cnt (devirt
))
3092 if (dump_enabled_p ())
3094 location_t locus
= gimple_location_safe (e
->call_stmt
);
3095 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS
, locus
,
3096 "speculatively devirtualizing call in %s/%i to %s/%i\n",
3097 n
->name (), n
->order
,
3098 likely_target
->name (),
3099 likely_target
->order
);
3101 if (!likely_target
->can_be_discarded_p ())
3104 alias
= dyn_cast
<cgraph_node
*> (likely_target
->noninterposable_alias ());
3106 likely_target
= alias
;
3110 cgraph_turn_edge_to_speculative
3111 (e
, likely_target
, e
->count
* 8 / 10, e
->frequency
* 8 / 10);
3115 inline_update_overall_summary (n
);
3120 "%i polymorphic calls, %i devirtualized,"
3121 " %i speculatively devirtualized, %i cold\n"
3122 "%i have multiple targets, %i overwritable,"
3123 " %i already speculated (%i agree, %i disagree),"
3124 " %i external, %i not defined, %i artificial\n",
3125 npolymorphic
, ndevirtualized
, nconverted
, ncold
,
3126 nmultiple
, noverwritable
, nspeculated
, nok
, nwrong
,
3127 nexternal
, nnotdefined
, nartificial
);
3128 return ndevirtualized
? TODO_remove_functions
: 0;
3133 const pass_data pass_data_ipa_devirt
=
3135 IPA_PASS
, /* type */
3136 "devirt", /* name */
3137 OPTGROUP_NONE
, /* optinfo_flags */
3138 TV_IPA_DEVIRT
, /* tv_id */
3139 0, /* properties_required */
3140 0, /* properties_provided */
3141 0, /* properties_destroyed */
3142 0, /* todo_flags_start */
3143 ( TODO_dump_symtab
), /* todo_flags_finish */
3146 class pass_ipa_devirt
: public ipa_opt_pass_d
3149 pass_ipa_devirt (gcc::context
*ctxt
)
3150 : ipa_opt_pass_d (pass_data_ipa_devirt
, ctxt
,
3151 NULL
, /* generate_summary */
3152 NULL
, /* write_summary */
3153 NULL
, /* read_summary */
3154 NULL
, /* write_optimization_summary */
3155 NULL
, /* read_optimization_summary */
3156 NULL
, /* stmt_fixup */
3157 0, /* function_transform_todo_flags_start */
3158 NULL
, /* function_transform */
3159 NULL
) /* variable_transform */
3162 /* opt_pass methods: */
3163 virtual bool gate (function
*)
3165 return (flag_devirtualize
3166 && flag_devirtualize_speculatively
3170 virtual unsigned int execute (function
*) { return ipa_devirt (); }
3172 }; // class pass_ipa_devirt
3177 make_pass_ipa_devirt (gcc::context
*ctxt
)
3179 return new pass_ipa_devirt (ctxt
);
3182 #include "gt-ipa-devirt.h"