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eefe9a99 JH |
1 | /* Basic IPA utilities for type inheritance graph construction and |
2 | devirtualization. | |
23a5b65a | 3 | Copyright (C) 2013-2014 Free Software Foundation, Inc. |
eefe9a99 JH |
4 | Contributed by Jan Hubicka |
5 | ||
6 | This file is part of GCC. | |
7 | ||
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 | |
11 | version. | |
12 | ||
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 | |
16 | for more details. | |
17 | ||
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/>. */ | |
21 | ||
22 | /* Brief vocalburary: | |
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. | |
38 | ||
39 | OTR = OBJ_TYPE_REF | |
0e1474e5 | 40 | This is the Gimple representation of type information of a polymorphic call. |
eefe9a99 JH |
41 | It contains two parameters: |
42 | otr_type is a type of class whose method is called. | |
0e1474e5 | 43 | otr_token is the index into virtual table where address is taken. |
eefe9a99 JH |
44 | |
45 | BINFO | |
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. | |
49 | ||
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 | |
52 | BINFO_VTABLE. | |
53 | ||
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 | |
0e1474e5 | 58 | virtual table of the base type. Also BINFO_OFFSET specifies |
eefe9a99 JH |
59 | offset of the base within the type. |
60 | ||
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). | |
66 | ||
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 | |
70 | base type. | |
71 | ||
72 | token | |
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 | |
0e1474e5 | 75 | or from DECL_VINDEX of a given virtual table. |
eefe9a99 JH |
76 | |
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. | |
81 | ||
82 | What we do here: | |
83 | ||
84 | build_type_inheritance_graph triggers a construction of the type inheritance | |
85 | graph. | |
86 | ||
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 | |
0e1474e5 | 89 | inserted into the graph. Also types without virtual methods are not |
eefe9a99 JH |
90 | represented at all, though it may be easy to add this. |
91 | ||
92 | The inheritance graph is represented as follows: | |
93 | ||
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) | |
97 | ||
0e1474e5 | 98 | Edges are represented by odr_type->base and odr_type->derived_types. |
eefe9a99 JH |
99 | At the moment we do not track offsets of types for multiple inheritance. |
100 | Adding this is easy. | |
101 | ||
102 | possible_polymorphic_call_targets returns, given an parameters found in | |
103 | indirect polymorphic edge all possible polymorphic call targets of the call. | |
bbc9396b JH |
104 | |
105 | pass_ipa_devirt performs simple speculative devirtualization. | |
eefe9a99 JH |
106 | */ |
107 | ||
108 | #include "config.h" | |
109 | #include "system.h" | |
110 | #include "coretypes.h" | |
111 | #include "tm.h" | |
4d648807 | 112 | #include "tree.h" |
d8a2d370 DN |
113 | #include "print-tree.h" |
114 | #include "calls.h" | |
eefe9a99 | 115 | #include "cgraph.h" |
d8a2d370 | 116 | #include "expr.h" |
eefe9a99 | 117 | #include "tree-pass.h" |
eefe9a99 JH |
118 | #include "pointer-set.h" |
119 | #include "target.h" | |
120 | #include "hash-table.h" | |
121 | #include "tree-pretty-print.h" | |
122 | #include "ipa-utils.h" | |
2fb9a547 AM |
123 | #include "tree-ssa-alias.h" |
124 | #include "internal-fn.h" | |
125 | #include "gimple-fold.h" | |
126 | #include "gimple-expr.h" | |
eefe9a99 | 127 | #include "gimple.h" |
bbc9396b | 128 | #include "ipa-inline.h" |
61a74079 | 129 | #include "diagnostic.h" |
68377e53 | 130 | #include "tree-dfa.h" |
ec77d61f JH |
131 | #include "demangle.h" |
132 | ||
133 | static bool odr_violation_reported = false; | |
68377e53 JH |
134 | |
135 | /* Dummy polymorphic call context. */ | |
136 | ||
137 | const ipa_polymorphic_call_context ipa_dummy_polymorphic_call_context | |
138 | = {0, NULL, false, true}; | |
eefe9a99 | 139 | |
0e1474e5 JH |
140 | /* Pointer set of all call targets appearing in the cache. */ |
141 | static pointer_set_t *cached_polymorphic_call_targets; | |
142 | ||
eefe9a99 JH |
143 | /* The node of type inheritance graph. For each type unique in |
144 | One Defintion Rule (ODR) sense, we produce one node linking all | |
145 | main variants of types equivalent to it, bases and derived types. */ | |
146 | ||
147 | struct GTY(()) odr_type_d | |
148 | { | |
eefe9a99 JH |
149 | /* leader type. */ |
150 | tree type; | |
151 | /* All bases. */ | |
152 | vec<odr_type> GTY((skip)) bases; | |
153 | /* All derrived types with virtual methods seen in unit. */ | |
154 | vec<odr_type> GTY((skip)) derived_types; | |
0e1474e5 | 155 | |
61a74079 JH |
156 | /* All equivalent types, if more than one. */ |
157 | vec<tree, va_gc> *types; | |
158 | /* Set of all equivalent types, if NON-NULL. */ | |
159 | pointer_set_t * GTY((skip)) types_set; | |
160 | ||
0e1474e5 JH |
161 | /* Unique ID indexing the type in odr_types array. */ |
162 | int id; | |
eefe9a99 JH |
163 | /* Is it in anonymous namespace? */ |
164 | bool anonymous_namespace; | |
2d1644bf JH |
165 | /* Do we know about all derivations of given type? */ |
166 | bool all_derivations_known; | |
eefe9a99 JH |
167 | }; |
168 | ||
169 | ||
0e1474e5 JH |
170 | /* Return true if BINFO corresponds to a type with virtual methods. |
171 | ||
172 | Every type has several BINFOs. One is the BINFO associated by the type | |
173 | while other represents bases of derived types. The BINFOs representing | |
174 | bases do not have BINFO_VTABLE pointer set when this is the single | |
175 | inheritance (because vtables are shared). Look up the BINFO of type | |
176 | and check presence of its vtable. */ | |
eefe9a99 JH |
177 | |
178 | static inline bool | |
179 | polymorphic_type_binfo_p (tree binfo) | |
180 | { | |
181 | /* See if BINFO's type has an virtual table associtated with it. */ | |
182 | return BINFO_VTABLE (TYPE_BINFO (BINFO_TYPE (binfo))); | |
183 | } | |
184 | ||
2d1644bf JH |
185 | /* Return TRUE if all derived types of T are known and thus |
186 | we may consider the walk of derived type complete. | |
187 | ||
188 | This is typically true only for final anonymous namespace types and types | |
189 | defined within functions (that may be COMDAT and thus shared across units, | |
190 | but with the same set of derived types). */ | |
191 | ||
192 | static bool | |
193 | type_all_derivations_known_p (tree t) | |
194 | { | |
195 | if (TYPE_FINAL_P (t)) | |
196 | return true; | |
197 | if (flag_ltrans) | |
198 | return false; | |
199 | if (type_in_anonymous_namespace_p (t)) | |
200 | return true; | |
201 | return (decl_function_context (TYPE_NAME (t)) != NULL); | |
202 | } | |
203 | ||
204 | /* Return TURE if type's constructors are all visible. */ | |
205 | ||
206 | static bool | |
207 | type_all_ctors_visible_p (tree t) | |
208 | { | |
209 | return !flag_ltrans | |
210 | && cgraph_state >= CGRAPH_STATE_CONSTRUCTION | |
211 | /* We can not always use type_all_derivations_known_p. | |
212 | For function local types we must assume case where | |
213 | the function is COMDAT and shared in between units. | |
214 | ||
215 | TODO: These cases are quite easy to get, but we need | |
216 | to keep track of C++ privatizing via -Wno-weak | |
217 | as well as the IPA privatizing. */ | |
218 | && type_in_anonymous_namespace_p (t); | |
219 | } | |
220 | ||
221 | /* Return TRUE if type may have instance. */ | |
222 | ||
223 | static bool | |
224 | type_possibly_instantiated_p (tree t) | |
225 | { | |
226 | tree vtable; | |
227 | varpool_node *vnode; | |
228 | ||
229 | /* TODO: Add abstract types here. */ | |
230 | if (!type_all_ctors_visible_p (t)) | |
231 | return true; | |
232 | ||
233 | vtable = BINFO_VTABLE (TYPE_BINFO (t)); | |
234 | if (TREE_CODE (vtable) == POINTER_PLUS_EXPR) | |
235 | vtable = TREE_OPERAND (TREE_OPERAND (vtable, 0), 0); | |
236 | vnode = varpool_get_node (vtable); | |
237 | return vnode && vnode->definition; | |
238 | } | |
239 | ||
eefe9a99 JH |
240 | /* One Definition Rule hashtable helpers. */ |
241 | ||
242 | struct odr_hasher | |
243 | { | |
244 | typedef odr_type_d value_type; | |
245 | typedef union tree_node compare_type; | |
246 | static inline hashval_t hash (const value_type *); | |
247 | static inline bool equal (const value_type *, const compare_type *); | |
248 | static inline void remove (value_type *); | |
249 | }; | |
250 | ||
251 | /* Produce hash based on type name. */ | |
252 | ||
253 | hashval_t | |
254 | hash_type_name (tree t) | |
255 | { | |
256 | gcc_checking_assert (TYPE_MAIN_VARIANT (t) == t); | |
257 | ||
258 | /* If not in LTO, all main variants are unique, so we can do | |
259 | pointer hash. */ | |
260 | if (!in_lto_p) | |
261 | return htab_hash_pointer (t); | |
262 | ||
263 | /* Anonymous types are unique. */ | |
264 | if (type_in_anonymous_namespace_p (t)) | |
265 | return htab_hash_pointer (t); | |
266 | ||
61a74079 JH |
267 | /* For polymorphic types, we can simply hash the virtual table. */ |
268 | if (TYPE_BINFO (t) && BINFO_VTABLE (TYPE_BINFO (t))) | |
269 | { | |
270 | tree v = BINFO_VTABLE (TYPE_BINFO (t)); | |
271 | hashval_t hash = 0; | |
272 | ||
273 | if (TREE_CODE (v) == POINTER_PLUS_EXPR) | |
274 | { | |
275 | hash = TREE_INT_CST_LOW (TREE_OPERAND (v, 1)); | |
276 | v = TREE_OPERAND (TREE_OPERAND (v, 0), 0); | |
277 | } | |
278 | ||
279 | v = DECL_ASSEMBLER_NAME (v); | |
61a74079 JH |
280 | hash = iterative_hash_hashval_t (hash, htab_hash_pointer (v)); |
281 | return hash; | |
282 | } | |
283 | ||
eefe9a99 JH |
284 | /* Rest is not implemented yet. */ |
285 | gcc_unreachable (); | |
286 | } | |
287 | ||
288 | /* Return the computed hashcode for ODR_TYPE. */ | |
289 | ||
290 | inline hashval_t | |
291 | odr_hasher::hash (const value_type *odr_type) | |
292 | { | |
293 | return hash_type_name (odr_type->type); | |
294 | } | |
295 | ||
0e1474e5 | 296 | /* Compare types T1 and T2 and return true if they are |
eefe9a99 JH |
297 | equivalent. */ |
298 | ||
299 | inline bool | |
300 | odr_hasher::equal (const value_type *t1, const compare_type *ct2) | |
301 | { | |
302 | tree t2 = const_cast <tree> (ct2); | |
303 | ||
304 | gcc_checking_assert (TYPE_MAIN_VARIANT (ct2) == ct2); | |
305 | if (t1->type == t2) | |
306 | return true; | |
307 | if (!in_lto_p) | |
308 | return false; | |
309 | return types_same_for_odr (t1->type, t2); | |
310 | } | |
311 | ||
0e1474e5 | 312 | /* Free ODR type V. */ |
eefe9a99 JH |
313 | |
314 | inline void | |
315 | odr_hasher::remove (value_type *v) | |
316 | { | |
317 | v->bases.release (); | |
318 | v->derived_types.release (); | |
61a74079 JH |
319 | if (v->types_set) |
320 | pointer_set_destroy (v->types_set); | |
eefe9a99 JH |
321 | ggc_free (v); |
322 | } | |
323 | ||
324 | /* ODR type hash used to lookup ODR type based on tree type node. */ | |
325 | ||
326 | typedef hash_table <odr_hasher> odr_hash_type; | |
327 | static odr_hash_type odr_hash; | |
328 | ||
329 | /* ODR types are also stored into ODR_TYPE vector to allow consistent | |
330 | walking. Bases appear before derived types. Vector is garbage collected | |
331 | so we won't end up visiting empty types. */ | |
332 | ||
333 | static GTY(()) vec <odr_type, va_gc> *odr_types_ptr; | |
334 | #define odr_types (*odr_types_ptr) | |
335 | ||
61a74079 JH |
336 | /* TYPE is equivalent to VAL by ODR, but its tree representation differs |
337 | from VAL->type. This may happen in LTO where tree merging did not merge | |
338 | all variants of the same type. It may or may not mean the ODR violation. | |
339 | Add it to the list of duplicates and warn on some violations. */ | |
340 | ||
341 | static void | |
342 | add_type_duplicate (odr_type val, tree type) | |
343 | { | |
344 | if (!val->types_set) | |
345 | val->types_set = pointer_set_create (); | |
346 | ||
347 | /* See if this duplicate is new. */ | |
348 | if (!pointer_set_insert (val->types_set, type)) | |
349 | { | |
350 | bool merge = true; | |
351 | bool base_mismatch = false; | |
352 | gcc_assert (in_lto_p); | |
353 | vec_safe_push (val->types, type); | |
354 | unsigned int i,j; | |
355 | ||
356 | /* First we compare memory layout. */ | |
357 | if (!types_compatible_p (val->type, type)) | |
358 | { | |
359 | merge = false; | |
ec77d61f | 360 | odr_violation_reported = true; |
61a74079 JH |
361 | if (BINFO_VTABLE (TYPE_BINFO (val->type)) |
362 | && warning_at (DECL_SOURCE_LOCATION (TYPE_NAME (type)), 0, | |
363 | "type %qD violates one definition rule ", | |
364 | type)) | |
365 | inform (DECL_SOURCE_LOCATION (TYPE_NAME (val->type)), | |
366 | "a type with the same name but different layout is " | |
367 | "defined in another translation unit"); | |
61a74079 JH |
368 | if (cgraph_dump_file) |
369 | { | |
370 | fprintf (cgraph_dump_file, "ODR violation or merging or ODR type bug?\n"); | |
371 | ||
372 | print_node (cgraph_dump_file, "", val->type, 0); | |
373 | putc ('\n',cgraph_dump_file); | |
374 | print_node (cgraph_dump_file, "", type, 0); | |
375 | putc ('\n',cgraph_dump_file); | |
376 | } | |
377 | } | |
378 | ||
379 | /* Next sanity check that bases are the same. If not, we will end | |
380 | up producing wrong answers. */ | |
381 | for (j = 0, i = 0; i < BINFO_N_BASE_BINFOS (TYPE_BINFO (type)); i++) | |
382 | if (polymorphic_type_binfo_p (BINFO_BASE_BINFO (TYPE_BINFO (type), i))) | |
383 | { | |
384 | odr_type base = get_odr_type | |
385 | (BINFO_TYPE | |
386 | (BINFO_BASE_BINFO (TYPE_BINFO (type), | |
387 | i)), | |
388 | true); | |
389 | if (val->bases.length () <= j || val->bases[j] != base) | |
390 | base_mismatch = true; | |
391 | j++; | |
392 | } | |
393 | if (base_mismatch) | |
394 | { | |
395 | merge = false; | |
ec77d61f | 396 | odr_violation_reported = true; |
61a74079 JH |
397 | |
398 | if (warning_at (DECL_SOURCE_LOCATION (TYPE_NAME (type)), 0, | |
399 | "type %qD violates one definition rule ", | |
400 | type)) | |
401 | inform (DECL_SOURCE_LOCATION (TYPE_NAME (val->type)), | |
402 | "a type with the same name but different bases is " | |
403 | "defined in another translation unit"); | |
404 | if (cgraph_dump_file) | |
405 | { | |
406 | fprintf (cgraph_dump_file, "ODR bse violation or merging bug?\n"); | |
407 | ||
408 | print_node (cgraph_dump_file, "", val->type, 0); | |
409 | putc ('\n',cgraph_dump_file); | |
410 | print_node (cgraph_dump_file, "", type, 0); | |
411 | putc ('\n',cgraph_dump_file); | |
412 | } | |
413 | } | |
414 | ||
415 | /* Regularize things a little. During LTO same types may come with | |
416 | different BINFOs. Either because their virtual table was | |
417 | not merged by tree merging and only later at decl merging or | |
418 | because one type comes with external vtable, while other | |
419 | with internal. We want to merge equivalent binfos to conserve | |
420 | memory and streaming overhead. | |
421 | ||
422 | The external vtables are more harmful: they contain references | |
423 | to external declarations of methods that may be defined in the | |
424 | merged LTO unit. For this reason we absolutely need to remove | |
425 | them and replace by internal variants. Not doing so will lead | |
426 | to incomplete answers from possible_polymorphic_call_targets. */ | |
427 | if (!flag_ltrans && merge) | |
428 | { | |
429 | tree master_binfo = TYPE_BINFO (val->type); | |
430 | tree v1 = BINFO_VTABLE (master_binfo); | |
431 | tree v2 = BINFO_VTABLE (TYPE_BINFO (type)); | |
432 | ||
433 | if (TREE_CODE (v1) == POINTER_PLUS_EXPR) | |
434 | { | |
435 | gcc_assert (TREE_CODE (v2) == POINTER_PLUS_EXPR | |
436 | && operand_equal_p (TREE_OPERAND (v1, 1), | |
437 | TREE_OPERAND (v2, 1), 0)); | |
438 | v1 = TREE_OPERAND (TREE_OPERAND (v1, 0), 0); | |
439 | v2 = TREE_OPERAND (TREE_OPERAND (v2, 0), 0); | |
440 | } | |
441 | gcc_assert (DECL_ASSEMBLER_NAME (v1) | |
442 | == DECL_ASSEMBLER_NAME (v2)); | |
443 | ||
444 | if (DECL_EXTERNAL (v1) && !DECL_EXTERNAL (v2)) | |
445 | { | |
446 | unsigned int i; | |
447 | ||
448 | TYPE_BINFO (val->type) = TYPE_BINFO (type); | |
c3284718 | 449 | for (i = 0; i < val->types->length (); i++) |
61a74079 JH |
450 | { |
451 | if (TYPE_BINFO ((*val->types)[i]) | |
452 | == master_binfo) | |
453 | TYPE_BINFO ((*val->types)[i]) = TYPE_BINFO (type); | |
454 | } | |
455 | } | |
456 | else | |
457 | TYPE_BINFO (type) = master_binfo; | |
458 | } | |
459 | } | |
460 | } | |
461 | ||
eefe9a99 JH |
462 | /* Get ODR type hash entry for TYPE. If INSERT is true, create |
463 | possibly new entry. */ | |
464 | ||
465 | odr_type | |
466 | get_odr_type (tree type, bool insert) | |
467 | { | |
468 | odr_type_d **slot; | |
469 | odr_type val; | |
470 | hashval_t hash; | |
471 | ||
472 | type = TYPE_MAIN_VARIANT (type); | |
473 | gcc_checking_assert (TYPE_MAIN_VARIANT (type) == type); | |
474 | hash = hash_type_name (type); | |
475 | slot = odr_hash.find_slot_with_hash (type, hash, insert ? INSERT : NO_INSERT); | |
476 | if (!slot) | |
477 | return NULL; | |
478 | ||
479 | /* See if we already have entry for type. */ | |
480 | if (*slot) | |
481 | { | |
482 | val = *slot; | |
483 | ||
61a74079 JH |
484 | /* With LTO we need to support multiple tree representation of |
485 | the same ODR type. */ | |
486 | if (val->type != type) | |
487 | add_type_duplicate (val, type); | |
eefe9a99 JH |
488 | } |
489 | else | |
490 | { | |
491 | tree binfo = TYPE_BINFO (type); | |
492 | unsigned int i; | |
493 | ||
494 | val = ggc_alloc_cleared_odr_type_d (); | |
495 | val->type = type; | |
496 | val->bases = vNULL; | |
497 | val->derived_types = vNULL; | |
0e1474e5 | 498 | val->anonymous_namespace = type_in_anonymous_namespace_p (type); |
2d1644bf | 499 | val->all_derivations_known = type_all_derivations_known_p (type); |
eefe9a99 JH |
500 | *slot = val; |
501 | for (i = 0; i < BINFO_N_BASE_BINFOS (binfo); i++) | |
502 | /* For now record only polymorphic types. other are | |
503 | pointless for devirtualization and we can not precisely | |
504 | determine ODR equivalency of these during LTO. */ | |
505 | if (polymorphic_type_binfo_p (BINFO_BASE_BINFO (binfo, i))) | |
506 | { | |
507 | odr_type base = get_odr_type (BINFO_TYPE (BINFO_BASE_BINFO (binfo, | |
508 | i)), | |
509 | true); | |
510 | base->derived_types.safe_push (val); | |
511 | val->bases.safe_push (base); | |
512 | } | |
513 | /* First record bases, then add into array so ids are increasing. */ | |
514 | if (odr_types_ptr) | |
c3284718 | 515 | val->id = odr_types.length (); |
eefe9a99 JH |
516 | vec_safe_push (odr_types_ptr, val); |
517 | } | |
518 | return val; | |
519 | } | |
520 | ||
521 | /* Dump ODR type T and all its derrived type. INDENT specify indentation for | |
522 | recusive printing. */ | |
523 | ||
524 | static void | |
525 | dump_odr_type (FILE *f, odr_type t, int indent=0) | |
526 | { | |
527 | unsigned int i; | |
528 | fprintf (f, "%*s type %i: ", indent * 2, "", t->id); | |
529 | print_generic_expr (f, t->type, TDF_SLIM); | |
2d1644bf JH |
530 | fprintf (f, "%s", t->anonymous_namespace ? " (anonymous namespace)":""); |
531 | fprintf (f, "%s\n", t->all_derivations_known ? " (derivations known)":""); | |
eefe9a99 JH |
532 | if (TYPE_NAME (t->type)) |
533 | { | |
534 | fprintf (f, "%*s defined at: %s:%i\n", indent * 2, "", | |
535 | DECL_SOURCE_FILE (TYPE_NAME (t->type)), | |
536 | DECL_SOURCE_LINE (TYPE_NAME (t->type))); | |
537 | } | |
c3284718 | 538 | if (t->bases.length ()) |
eefe9a99 JH |
539 | { |
540 | fprintf (f, "%*s base odr type ids: ", indent * 2, ""); | |
c3284718 | 541 | for (i = 0; i < t->bases.length (); i++) |
eefe9a99 JH |
542 | fprintf (f, " %i", t->bases[i]->id); |
543 | fprintf (f, "\n"); | |
544 | } | |
c3284718 | 545 | if (t->derived_types.length ()) |
eefe9a99 JH |
546 | { |
547 | fprintf (f, "%*s derived types:\n", indent * 2, ""); | |
c3284718 | 548 | for (i = 0; i < t->derived_types.length (); i++) |
eefe9a99 JH |
549 | dump_odr_type (f, t->derived_types[i], indent + 1); |
550 | } | |
551 | fprintf (f, "\n"); | |
552 | } | |
553 | ||
554 | /* Dump the type inheritance graph. */ | |
555 | ||
556 | static void | |
557 | dump_type_inheritance_graph (FILE *f) | |
558 | { | |
559 | unsigned int i; | |
0e1474e5 JH |
560 | if (!odr_types_ptr) |
561 | return; | |
eefe9a99 | 562 | fprintf (f, "\n\nType inheritance graph:\n"); |
c3284718 | 563 | for (i = 0; i < odr_types.length (); i++) |
eefe9a99 | 564 | { |
c3284718 | 565 | if (odr_types[i]->bases.length () == 0) |
eefe9a99 JH |
566 | dump_odr_type (f, odr_types[i]); |
567 | } | |
c3284718 | 568 | for (i = 0; i < odr_types.length (); i++) |
61a74079 | 569 | { |
c3284718 | 570 | if (odr_types[i]->types && odr_types[i]->types->length ()) |
61a74079 JH |
571 | { |
572 | unsigned int j; | |
573 | fprintf (f, "Duplicate tree types for odr type %i\n", i); | |
574 | print_node (f, "", odr_types[i]->type, 0); | |
c3284718 | 575 | for (j = 0; j < odr_types[i]->types->length (); j++) |
61a74079 JH |
576 | { |
577 | tree t; | |
578 | fprintf (f, "duplicate #%i\n", j); | |
579 | print_node (f, "", (*odr_types[i]->types)[j], 0); | |
580 | t = (*odr_types[i]->types)[j]; | |
581 | while (TYPE_P (t) && TYPE_CONTEXT (t)) | |
582 | { | |
583 | t = TYPE_CONTEXT (t); | |
584 | print_node (f, "", t, 0); | |
585 | } | |
586 | putc ('\n',f); | |
587 | } | |
588 | } | |
589 | } | |
eefe9a99 JH |
590 | } |
591 | ||
592 | /* Given method type T, return type of class it belongs to. | |
593 | Lookup this pointer and get its type. */ | |
594 | ||
64cbf23d | 595 | tree |
eefe9a99 JH |
596 | method_class_type (tree t) |
597 | { | |
598 | tree first_parm_type = TREE_VALUE (TYPE_ARG_TYPES (t)); | |
68377e53 | 599 | gcc_assert (TREE_CODE (t) == METHOD_TYPE); |
eefe9a99 JH |
600 | |
601 | return TREE_TYPE (first_parm_type); | |
602 | } | |
603 | ||
604 | /* Initialize IPA devirt and build inheritance tree graph. */ | |
605 | ||
606 | void | |
607 | build_type_inheritance_graph (void) | |
608 | { | |
b270b096 | 609 | struct symtab_node *n; |
eefe9a99 JH |
610 | FILE *inheritance_dump_file; |
611 | int flags; | |
612 | ||
613 | if (odr_hash.is_created ()) | |
614 | return; | |
615 | timevar_push (TV_IPA_INHERITANCE); | |
616 | inheritance_dump_file = dump_begin (TDI_inheritance, &flags); | |
617 | odr_hash.create (23); | |
618 | ||
619 | /* We reconstruct the graph starting of types of all methods seen in the | |
620 | the unit. */ | |
b270b096 JH |
621 | FOR_EACH_SYMBOL (n) |
622 | if (is_a <cgraph_node> (n) | |
623 | && DECL_VIRTUAL_P (n->decl) | |
67348ccc DM |
624 | && symtab_real_symbol_p (n)) |
625 | get_odr_type (method_class_type (TREE_TYPE (n->decl)), true); | |
b270b096 JH |
626 | |
627 | /* Look also for virtual tables of types that do not define any methods. | |
628 | ||
629 | We need it in a case where class B has virtual base of class A | |
630 | re-defining its virtual method and there is class C with no virtual | |
631 | methods with B as virtual base. | |
632 | ||
633 | Here we output B's virtual method in two variant - for non-virtual | |
634 | and virtual inheritance. B's virtual table has non-virtual version, | |
635 | while C's has virtual. | |
636 | ||
637 | For this reason we need to know about C in order to include both | |
638 | variants of B. More correctly, record_target_from_binfo should | |
639 | add both variants of the method when walking B, but we have no | |
640 | link in between them. | |
641 | ||
642 | We rely on fact that either the method is exported and thus we | |
643 | assume it is called externally or C is in anonymous namespace and | |
644 | thus we will see the vtable. */ | |
645 | ||
646 | else if (is_a <varpool_node> (n) | |
647 | && DECL_VIRTUAL_P (n->decl) | |
648 | && TREE_CODE (DECL_CONTEXT (n->decl)) == RECORD_TYPE | |
649 | && TYPE_BINFO (DECL_CONTEXT (n->decl)) | |
650 | && polymorphic_type_binfo_p (TYPE_BINFO (DECL_CONTEXT (n->decl)))) | |
651 | get_odr_type (DECL_CONTEXT (n->decl), true); | |
eefe9a99 JH |
652 | if (inheritance_dump_file) |
653 | { | |
654 | dump_type_inheritance_graph (inheritance_dump_file); | |
655 | dump_end (TDI_inheritance, inheritance_dump_file); | |
656 | } | |
657 | timevar_pop (TV_IPA_INHERITANCE); | |
658 | } | |
659 | ||
ccb05ef2 JH |
660 | /* Return true if N has reference from live virtual table |
661 | (and thus can be a destination of polymorphic call). | |
662 | Be conservatively correct when callgraph is not built or | |
663 | if the method may be referred externally. */ | |
664 | ||
665 | static bool | |
666 | referenced_from_vtable_p (struct cgraph_node *node) | |
667 | { | |
668 | int i; | |
669 | struct ipa_ref *ref; | |
670 | bool found = false; | |
671 | ||
672 | if (node->externally_visible | |
673 | || node->used_from_other_partition) | |
674 | return true; | |
675 | ||
676 | /* Keep this test constant time. | |
677 | It is unlikely this can happen except for the case where speculative | |
678 | devirtualization introduced many speculative edges to this node. | |
679 | In this case the target is very likely alive anyway. */ | |
680 | if (node->ref_list.referring.length () > 100) | |
681 | return true; | |
682 | ||
683 | /* We need references built. */ | |
684 | if (cgraph_state <= CGRAPH_STATE_CONSTRUCTION) | |
685 | return true; | |
686 | ||
687 | for (i = 0; ipa_ref_list_referring_iterate (&node->ref_list, | |
688 | i, ref); i++) | |
689 | ||
690 | if ((ref->use == IPA_REF_ALIAS | |
691 | && referenced_from_vtable_p (cgraph (ref->referring))) | |
692 | || (ref->use == IPA_REF_ADDR | |
693 | && TREE_CODE (ref->referring->decl) == VAR_DECL | |
694 | && DECL_VIRTUAL_P (ref->referring->decl))) | |
695 | { | |
696 | found = true; | |
697 | break; | |
698 | } | |
699 | return found; | |
700 | } | |
701 | ||
68377e53 | 702 | /* If TARGET has associated node, record it in the NODES array. |
ec77d61f JH |
703 | CAN_REFER specify if program can refer to the target directly. |
704 | if TARGET is unknown (NULL) or it can not be inserted (for example because | |
705 | its body was already removed and there is no way to refer to it), clear | |
706 | COMPLETEP. */ | |
eefe9a99 JH |
707 | |
708 | static void | |
709 | maybe_record_node (vec <cgraph_node *> &nodes, | |
68377e53 | 710 | tree target, pointer_set_t *inserted, |
ec77d61f | 711 | bool can_refer, |
68377e53 | 712 | bool *completep) |
eefe9a99 JH |
713 | { |
714 | struct cgraph_node *target_node; | |
88f592e3 JH |
715 | |
716 | /* cxa_pure_virtual and __builtin_unreachable do not need to be added into | |
717 | list of targets; the runtime effect of calling them is undefined. | |
718 | Only "real" virtual methods should be accounted. */ | |
719 | if (target && TREE_CODE (TREE_TYPE (target)) != METHOD_TYPE) | |
720 | return; | |
eefe9a99 | 721 | |
ec77d61f JH |
722 | if (!can_refer) |
723 | { | |
724 | /* The only case when method of anonymous namespace becomes unreferable | |
725 | is when we completely optimized it out. */ | |
726 | if (flag_ltrans | |
727 | || !target | |
88f592e3 | 728 | || !type_in_anonymous_namespace_p (DECL_CONTEXT (target))) |
ec77d61f JH |
729 | *completep = false; |
730 | return; | |
731 | } | |
732 | ||
88f592e3 | 733 | if (!target) |
68377e53 JH |
734 | return; |
735 | ||
736 | target_node = cgraph_get_node (target); | |
737 | ||
ccb05ef2 JH |
738 | /* Method can only be called by polymorphic call if any |
739 | of vtables refering to it are alive. | |
740 | ||
741 | While this holds for non-anonymous functions, too, there are | |
742 | cases where we want to keep them in the list; for example | |
743 | inline functions with -fno-weak are static, but we still | |
744 | may devirtualize them when instance comes from other unit. | |
745 | The same holds for LTO. | |
746 | ||
747 | Currently we ignore these functions in speculative devirtualization. | |
748 | ??? Maybe it would make sense to be more aggressive for LTO even | |
749 | eslewhere. */ | |
750 | if (!flag_ltrans | |
751 | && type_in_anonymous_namespace_p (DECL_CONTEXT (target)) | |
752 | && (!target_node | |
753 | || !referenced_from_vtable_p (target_node))) | |
754 | ; | |
755 | /* See if TARGET is useful function we can deal with. */ | |
756 | else if (target_node != NULL | |
757 | && (TREE_PUBLIC (target) | |
758 | || DECL_EXTERNAL (target) | |
759 | || target_node->definition) | |
760 | && symtab_real_symbol_p (target_node)) | |
0e1474e5 | 761 | { |
68377e53 JH |
762 | gcc_assert (!target_node->global.inlined_to); |
763 | gcc_assert (symtab_real_symbol_p (target_node)); | |
764 | if (!pointer_set_insert (inserted, target)) | |
765 | { | |
766 | pointer_set_insert (cached_polymorphic_call_targets, | |
767 | target_node); | |
768 | nodes.safe_push (target_node); | |
769 | } | |
0e1474e5 | 770 | } |
68377e53 | 771 | else if (completep |
2d1644bf JH |
772 | && (!type_in_anonymous_namespace_p |
773 | (DECL_CONTEXT (target)) | |
774 | || flag_ltrans)) | |
0439a947 | 775 | *completep = false; |
eefe9a99 JH |
776 | } |
777 | ||
68377e53 JH |
778 | /* See if BINFO's type match OUTER_TYPE. If so, lookup |
779 | BINFO of subtype of OTR_TYPE at OFFSET and in that BINFO find | |
2d1644bf JH |
780 | method in vtable and insert method to NODES array |
781 | or BASES_TO_CONSIDER if this array is non-NULL. | |
eefe9a99 JH |
782 | Otherwise recurse to base BINFOs. |
783 | This match what get_binfo_at_offset does, but with offset | |
784 | being unknown. | |
785 | ||
a3788dde JH |
786 | TYPE_BINFOS is a stack of BINFOS of types with defined |
787 | virtual table seen on way from class type to BINFO. | |
eefe9a99 JH |
788 | |
789 | MATCHED_VTABLES tracks virtual tables we already did lookup | |
68377e53 JH |
790 | for virtual function in. INSERTED tracks nodes we already |
791 | inserted. | |
3462aa02 JH |
792 | |
793 | ANONYMOUS is true if BINFO is part of anonymous namespace. | |
ec77d61f JH |
794 | |
795 | Clear COMPLETEP when we hit unreferable target. | |
eefe9a99 JH |
796 | */ |
797 | ||
798 | static void | |
68377e53 | 799 | record_target_from_binfo (vec <cgraph_node *> &nodes, |
2d1644bf | 800 | vec <tree> *bases_to_consider, |
68377e53 JH |
801 | tree binfo, |
802 | tree otr_type, | |
a3788dde | 803 | vec <tree> &type_binfos, |
68377e53 JH |
804 | HOST_WIDE_INT otr_token, |
805 | tree outer_type, | |
806 | HOST_WIDE_INT offset, | |
807 | pointer_set_t *inserted, | |
808 | pointer_set_t *matched_vtables, | |
ec77d61f JH |
809 | bool anonymous, |
810 | bool *completep) | |
eefe9a99 JH |
811 | { |
812 | tree type = BINFO_TYPE (binfo); | |
813 | int i; | |
814 | tree base_binfo; | |
815 | ||
eefe9a99 | 816 | |
a3788dde JH |
817 | if (BINFO_VTABLE (binfo)) |
818 | type_binfos.safe_push (binfo); | |
68377e53 | 819 | if (types_same_for_odr (type, outer_type)) |
eefe9a99 | 820 | { |
a3788dde JH |
821 | int i; |
822 | tree type_binfo = NULL; | |
823 | ||
824 | /* Lookup BINFO with virtual table. For normal types it is always last | |
825 | binfo on stack. */ | |
826 | for (i = type_binfos.length () - 1; i >= 0; i--) | |
827 | if (BINFO_OFFSET (type_binfos[i]) == BINFO_OFFSET (binfo)) | |
828 | { | |
829 | type_binfo = type_binfos[i]; | |
830 | break; | |
831 | } | |
832 | if (BINFO_VTABLE (binfo)) | |
833 | type_binfos.pop (); | |
834 | /* If this is duplicated BINFO for base shared by virtual inheritance, | |
835 | we may not have its associated vtable. This is not a problem, since | |
836 | we will walk it on the other path. */ | |
837 | if (!type_binfo) | |
6d6af792 | 838 | return; |
68377e53 JH |
839 | tree inner_binfo = get_binfo_at_offset (type_binfo, |
840 | offset, otr_type); | |
ec77d61f JH |
841 | if (!inner_binfo) |
842 | { | |
843 | gcc_assert (odr_violation_reported); | |
844 | return; | |
845 | } | |
3462aa02 JH |
846 | /* For types in anonymous namespace first check if the respective vtable |
847 | is alive. If not, we know the type can't be called. */ | |
848 | if (!flag_ltrans && anonymous) | |
849 | { | |
68377e53 | 850 | tree vtable = BINFO_VTABLE (inner_binfo); |
2c8326a5 | 851 | varpool_node *vnode; |
3462aa02 JH |
852 | |
853 | if (TREE_CODE (vtable) == POINTER_PLUS_EXPR) | |
854 | vtable = TREE_OPERAND (TREE_OPERAND (vtable, 0), 0); | |
855 | vnode = varpool_get_node (vtable); | |
67348ccc | 856 | if (!vnode || !vnode->definition) |
3462aa02 JH |
857 | return; |
858 | } | |
68377e53 | 859 | gcc_assert (inner_binfo); |
2d1644bf JH |
860 | if (bases_to_consider |
861 | ? !pointer_set_contains (matched_vtables, BINFO_VTABLE (inner_binfo)) | |
862 | : !pointer_set_insert (matched_vtables, BINFO_VTABLE (inner_binfo))) | |
68377e53 | 863 | { |
ec77d61f JH |
864 | bool can_refer; |
865 | tree target = gimple_get_virt_method_for_binfo (otr_token, | |
866 | inner_binfo, | |
867 | &can_refer); | |
2d1644bf JH |
868 | if (!bases_to_consider) |
869 | maybe_record_node (nodes, target, inserted, can_refer, completep); | |
870 | /* Destructors are never called via construction vtables. */ | |
871 | else if (!target || !DECL_CXX_DESTRUCTOR_P (target)) | |
872 | bases_to_consider->safe_push (target); | |
68377e53 | 873 | } |
eefe9a99 JH |
874 | return; |
875 | } | |
876 | ||
877 | /* Walk bases. */ | |
878 | for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++) | |
879 | /* Walking bases that have no virtual method is pointless excercise. */ | |
880 | if (polymorphic_type_binfo_p (base_binfo)) | |
2d1644bf | 881 | record_target_from_binfo (nodes, bases_to_consider, base_binfo, otr_type, |
a3788dde | 882 | type_binfos, |
68377e53 | 883 | otr_token, outer_type, offset, inserted, |
ec77d61f | 884 | matched_vtables, anonymous, completep); |
a3788dde JH |
885 | if (BINFO_VTABLE (binfo)) |
886 | type_binfos.pop (); | |
eefe9a99 JH |
887 | } |
888 | ||
889 | /* Lookup virtual methods matching OTR_TYPE (with OFFSET and OTR_TOKEN) | |
890 | of TYPE, insert them to NODES, recurse into derived nodes. | |
891 | INSERTED is used to avoid duplicate insertions of methods into NODES. | |
ec77d61f | 892 | MATCHED_VTABLES are used to avoid duplicate walking vtables. |
2d1644bf JH |
893 | Clear COMPLETEP if unreferable target is found. |
894 | ||
895 | If CONSIDER_CONSTURCTION is true, record to BASES_TO_CONSDIER | |
896 | all cases where BASE_SKIPPED is true (because the base is abstract | |
897 | class). */ | |
eefe9a99 JH |
898 | |
899 | static void | |
900 | possible_polymorphic_call_targets_1 (vec <cgraph_node *> &nodes, | |
901 | pointer_set_t *inserted, | |
902 | pointer_set_t *matched_vtables, | |
903 | tree otr_type, | |
904 | odr_type type, | |
68377e53 JH |
905 | HOST_WIDE_INT otr_token, |
906 | tree outer_type, | |
ec77d61f | 907 | HOST_WIDE_INT offset, |
2d1644bf JH |
908 | bool *completep, |
909 | vec <tree> &bases_to_consider, | |
910 | bool consider_construction) | |
eefe9a99 JH |
911 | { |
912 | tree binfo = TYPE_BINFO (type->type); | |
913 | unsigned int i; | |
a3788dde | 914 | vec <tree> type_binfos = vNULL; |
2d1644bf JH |
915 | bool possibly_instantiated = type_possibly_instantiated_p (type->type); |
916 | ||
917 | /* We may need to consider types w/o instances because of possible derived | |
918 | types using their methods either directly or via construction vtables. | |
919 | We are safe to skip them when all derivations are known, since we will | |
920 | handle them later. | |
921 | This is done by recording them to BASES_TO_CONSIDER array. */ | |
922 | if (possibly_instantiated || consider_construction) | |
923 | { | |
924 | record_target_from_binfo (nodes, | |
925 | (!possibly_instantiated | |
926 | && type_all_derivations_known_p (type->type)) | |
927 | ? &bases_to_consider : NULL, | |
928 | binfo, otr_type, type_binfos, otr_token, | |
929 | outer_type, offset, | |
930 | inserted, matched_vtables, | |
931 | type->anonymous_namespace, completep); | |
932 | } | |
a3788dde | 933 | type_binfos.release (); |
c3284718 | 934 | for (i = 0; i < type->derived_types.length (); i++) |
eefe9a99 JH |
935 | possible_polymorphic_call_targets_1 (nodes, inserted, |
936 | matched_vtables, | |
937 | otr_type, | |
938 | type->derived_types[i], | |
2d1644bf JH |
939 | otr_token, outer_type, offset, completep, |
940 | bases_to_consider, consider_construction); | |
eefe9a99 JH |
941 | } |
942 | ||
943 | /* Cache of queries for polymorphic call targets. | |
944 | ||
945 | Enumerating all call targets may get expensive when there are many | |
946 | polymorphic calls in the program, so we memoize all the previous | |
947 | queries and avoid duplicated work. */ | |
948 | ||
949 | struct polymorphic_call_target_d | |
950 | { | |
eefe9a99 | 951 | HOST_WIDE_INT otr_token; |
68377e53 JH |
952 | ipa_polymorphic_call_context context; |
953 | odr_type type; | |
eefe9a99 | 954 | vec <cgraph_node *> targets; |
ec77d61f JH |
955 | int nonconstruction_targets; |
956 | bool complete; | |
eefe9a99 JH |
957 | }; |
958 | ||
959 | /* Polymorphic call target cache helpers. */ | |
960 | ||
961 | struct polymorphic_call_target_hasher | |
962 | { | |
963 | typedef polymorphic_call_target_d value_type; | |
964 | typedef polymorphic_call_target_d compare_type; | |
965 | static inline hashval_t hash (const value_type *); | |
966 | static inline bool equal (const value_type *, const compare_type *); | |
967 | static inline void remove (value_type *); | |
968 | }; | |
969 | ||
970 | /* Return the computed hashcode for ODR_QUERY. */ | |
971 | ||
972 | inline hashval_t | |
973 | polymorphic_call_target_hasher::hash (const value_type *odr_query) | |
974 | { | |
68377e53 JH |
975 | hashval_t hash; |
976 | ||
977 | hash = iterative_hash_host_wide_int | |
978 | (odr_query->otr_token, | |
979 | odr_query->type->id); | |
980 | hash = iterative_hash_hashval_t (TYPE_UID (odr_query->context.outer_type), | |
981 | hash); | |
982 | hash = iterative_hash_host_wide_int (odr_query->context.offset, hash); | |
983 | return iterative_hash_hashval_t | |
984 | (((int)odr_query->context.maybe_in_construction << 1) | |
985 | | (int)odr_query->context.maybe_derived_type, hash); | |
eefe9a99 JH |
986 | } |
987 | ||
988 | /* Compare cache entries T1 and T2. */ | |
989 | ||
990 | inline bool | |
991 | polymorphic_call_target_hasher::equal (const value_type *t1, | |
992 | const compare_type *t2) | |
993 | { | |
68377e53 JH |
994 | return (t1->type == t2->type && t1->otr_token == t2->otr_token |
995 | && t1->context.offset == t2->context.offset | |
996 | && t1->context.outer_type == t2->context.outer_type | |
997 | && t1->context.maybe_in_construction | |
998 | == t2->context.maybe_in_construction | |
999 | && t1->context.maybe_derived_type == t2->context.maybe_derived_type); | |
eefe9a99 JH |
1000 | } |
1001 | ||
1002 | /* Remove entry in polymorphic call target cache hash. */ | |
1003 | ||
1004 | inline void | |
1005 | polymorphic_call_target_hasher::remove (value_type *v) | |
1006 | { | |
1007 | v->targets.release (); | |
1008 | free (v); | |
1009 | } | |
1010 | ||
1011 | /* Polymorphic call target query cache. */ | |
1012 | ||
1013 | typedef hash_table <polymorphic_call_target_hasher> | |
1014 | polymorphic_call_target_hash_type; | |
1015 | static polymorphic_call_target_hash_type polymorphic_call_target_hash; | |
eefe9a99 JH |
1016 | |
1017 | /* Destroy polymorphic call target query cache. */ | |
1018 | ||
1019 | static void | |
1020 | free_polymorphic_call_targets_hash () | |
1021 | { | |
0e1474e5 JH |
1022 | if (cached_polymorphic_call_targets) |
1023 | { | |
1024 | polymorphic_call_target_hash.dispose (); | |
1025 | pointer_set_destroy (cached_polymorphic_call_targets); | |
1026 | cached_polymorphic_call_targets = NULL; | |
1027 | } | |
eefe9a99 JH |
1028 | } |
1029 | ||
1030 | /* When virtual function is removed, we may need to flush the cache. */ | |
1031 | ||
1032 | static void | |
1033 | devirt_node_removal_hook (struct cgraph_node *n, void *d ATTRIBUTE_UNUSED) | |
1034 | { | |
0e1474e5 JH |
1035 | if (cached_polymorphic_call_targets |
1036 | && pointer_set_contains (cached_polymorphic_call_targets, n)) | |
eefe9a99 JH |
1037 | free_polymorphic_call_targets_hash (); |
1038 | } | |
1039 | ||
68377e53 JH |
1040 | /* CONTEXT->OUTER_TYPE is a type of memory object where object of EXPECTED_TYPE |
1041 | is contained at CONTEXT->OFFSET. Walk the memory representation of | |
1042 | CONTEXT->OUTER_TYPE and find the outermost class type that match | |
1043 | EXPECTED_TYPE or contain EXPECTED_TYPE as a base. Update CONTEXT | |
1044 | to represent it. | |
1045 | ||
1046 | For example when CONTEXT represents type | |
1047 | class A | |
1048 | { | |
1049 | int a; | |
1050 | class B b; | |
1051 | } | |
1052 | and we look for type at offset sizeof(int), we end up with B and offset 0. | |
1053 | If the same is produced by multiple inheritance, we end up with A and offset | |
1054 | sizeof(int). | |
1055 | ||
1056 | If we can not find corresponding class, give up by setting | |
1057 | CONTEXT->OUTER_TYPE to EXPECTED_TYPE and CONTEXT->OFFSET to NULL. | |
1058 | Return true when lookup was sucesful. */ | |
1059 | ||
1060 | static bool | |
1061 | get_class_context (ipa_polymorphic_call_context *context, | |
1062 | tree expected_type) | |
1063 | { | |
1064 | tree type = context->outer_type; | |
1065 | HOST_WIDE_INT offset = context->offset; | |
1066 | ||
1067 | /* Find the sub-object the constant actually refers to and mark whether it is | |
1068 | an artificial one (as opposed to a user-defined one). */ | |
1069 | while (true) | |
1070 | { | |
1071 | HOST_WIDE_INT pos, size; | |
1072 | tree fld; | |
1073 | ||
1074 | /* On a match, just return what we found. */ | |
1075 | if (TREE_CODE (type) == TREE_CODE (expected_type) | |
1076 | && types_same_for_odr (type, expected_type)) | |
1077 | { | |
3b4e93c3 JH |
1078 | /* Type can not contain itself on an non-zero offset. In that case |
1079 | just give up. */ | |
1080 | if (offset != 0) | |
1081 | goto give_up; | |
68377e53 JH |
1082 | gcc_assert (offset == 0); |
1083 | return true; | |
1084 | } | |
1085 | ||
1086 | /* Walk fields and find corresponding on at OFFSET. */ | |
1087 | if (TREE_CODE (type) == RECORD_TYPE) | |
1088 | { | |
1089 | for (fld = TYPE_FIELDS (type); fld; fld = DECL_CHAIN (fld)) | |
1090 | { | |
1091 | if (TREE_CODE (fld) != FIELD_DECL) | |
1092 | continue; | |
1093 | ||
1094 | pos = int_bit_position (fld); | |
1095 | size = tree_to_uhwi (DECL_SIZE (fld)); | |
1096 | if (pos <= offset && (pos + size) > offset) | |
1097 | break; | |
1098 | } | |
1099 | ||
1100 | if (!fld) | |
1101 | goto give_up; | |
1102 | ||
1103 | type = TREE_TYPE (fld); | |
1104 | offset -= pos; | |
1105 | /* DECL_ARTIFICIAL represents a basetype. */ | |
1106 | if (!DECL_ARTIFICIAL (fld)) | |
1107 | { | |
1108 | context->outer_type = type; | |
1109 | context->offset = offset; | |
1110 | /* As soon as we se an field containing the type, | |
1111 | we know we are not looking for derivations. */ | |
1112 | context->maybe_derived_type = false; | |
1113 | } | |
1114 | } | |
1115 | else if (TREE_CODE (type) == ARRAY_TYPE) | |
1116 | { | |
1117 | tree subtype = TREE_TYPE (type); | |
1118 | ||
1119 | /* Give up if we don't know array size. */ | |
1120 | if (!tree_fits_shwi_p (TYPE_SIZE (subtype)) | |
1121 | || !tree_to_shwi (TYPE_SIZE (subtype)) <= 0) | |
1122 | goto give_up; | |
1123 | offset = offset % tree_to_shwi (TYPE_SIZE (subtype)); | |
1124 | type = subtype; | |
1125 | context->outer_type = type; | |
1126 | context->offset = offset; | |
1127 | context->maybe_derived_type = false; | |
1128 | } | |
1129 | /* Give up on anything else. */ | |
1130 | else | |
1131 | goto give_up; | |
1132 | } | |
1133 | ||
1134 | /* If we failed to find subtype we look for, give up and fall back to the | |
1135 | most generic query. */ | |
1136 | give_up: | |
1137 | context->outer_type = expected_type; | |
1138 | context->offset = 0; | |
1139 | context->maybe_derived_type = true; | |
1140 | return false; | |
1141 | } | |
1142 | ||
1143 | /* Return true if OUTER_TYPE contains OTR_TYPE at OFFSET. */ | |
1144 | ||
1145 | static bool | |
1146 | contains_type_p (tree outer_type, HOST_WIDE_INT offset, | |
1147 | tree otr_type) | |
1148 | { | |
1149 | ipa_polymorphic_call_context context = {offset, outer_type, | |
1150 | false, true}; | |
1151 | return get_class_context (&context, otr_type); | |
1152 | } | |
1153 | ||
390675c8 JH |
1154 | /* Lookup base of BINFO that has virtual table VTABLE with OFFSET. */ |
1155 | ||
1156 | static tree | |
85942f45 JH |
1157 | subbinfo_with_vtable_at_offset (tree binfo, unsigned HOST_WIDE_INT offset, |
1158 | tree vtable) | |
390675c8 JH |
1159 | { |
1160 | tree v = BINFO_VTABLE (binfo); | |
1161 | int i; | |
1162 | tree base_binfo; | |
85942f45 | 1163 | unsigned HOST_WIDE_INT this_offset; |
390675c8 | 1164 | |
85942f45 JH |
1165 | if (v) |
1166 | { | |
1167 | if (!vtable_pointer_value_to_vtable (v, &v, &this_offset)) | |
1168 | gcc_unreachable (); | |
1169 | ||
1170 | if (offset == this_offset | |
1171 | && DECL_ASSEMBLER_NAME (v) == DECL_ASSEMBLER_NAME (vtable)) | |
1172 | return binfo; | |
1173 | } | |
390675c8 | 1174 | |
390675c8 JH |
1175 | for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++) |
1176 | if (polymorphic_type_binfo_p (base_binfo)) | |
1177 | { | |
1178 | base_binfo = subbinfo_with_vtable_at_offset (base_binfo, offset, vtable); | |
1179 | if (base_binfo) | |
1180 | return base_binfo; | |
1181 | } | |
1182 | return NULL; | |
1183 | } | |
1184 | ||
85942f45 JH |
1185 | /* T is known constant value of virtual table pointer. |
1186 | Store virtual table to V and its offset to OFFSET. | |
1187 | Return false if T does not look like virtual table reference. */ | |
390675c8 | 1188 | |
85942f45 JH |
1189 | bool |
1190 | vtable_pointer_value_to_vtable (tree t, tree *v, unsigned HOST_WIDE_INT *offset) | |
390675c8 JH |
1191 | { |
1192 | /* We expect &MEM[(void *)&virtual_table + 16B]. | |
1193 | We obtain object's BINFO from the context of the virtual table. | |
1194 | This one contains pointer to virtual table represented via | |
1195 | POINTER_PLUS_EXPR. Verify that this pointer match to what | |
1196 | we propagated through. | |
1197 | ||
1198 | In the case of virtual inheritance, the virtual tables may | |
1199 | be nested, i.e. the offset may be different from 16 and we may | |
1200 | need to dive into the type representation. */ | |
85942f45 | 1201 | if (TREE_CODE (t) == ADDR_EXPR |
390675c8 JH |
1202 | && TREE_CODE (TREE_OPERAND (t, 0)) == MEM_REF |
1203 | && TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 0)) == ADDR_EXPR | |
1204 | && TREE_CODE (TREE_OPERAND (TREE_OPERAND (t, 0), 1)) == INTEGER_CST | |
1205 | && (TREE_CODE (TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 0)) | |
1206 | == VAR_DECL) | |
1207 | && DECL_VIRTUAL_P (TREE_OPERAND (TREE_OPERAND | |
1208 | (TREE_OPERAND (t, 0), 0), 0))) | |
1209 | { | |
85942f45 JH |
1210 | *v = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (t, 0), 0), 0); |
1211 | *offset = tree_to_uhwi (TREE_OPERAND (TREE_OPERAND (t, 0), 1)); | |
1212 | return true; | |
390675c8 | 1213 | } |
85942f45 JH |
1214 | |
1215 | /* Alternative representation, used by C++ frontend is POINTER_PLUS_EXPR. | |
1216 | We need to handle it when T comes from static variable initializer or | |
1217 | BINFO. */ | |
1218 | if (TREE_CODE (t) == POINTER_PLUS_EXPR) | |
1219 | { | |
1220 | *offset = tree_to_uhwi (TREE_OPERAND (t, 1)); | |
1221 | t = TREE_OPERAND (t, 0); | |
1222 | } | |
1223 | else | |
1224 | *offset = 0; | |
1225 | ||
1226 | if (TREE_CODE (t) != ADDR_EXPR) | |
1227 | return false; | |
1228 | *v = TREE_OPERAND (t, 0); | |
1229 | return true; | |
1230 | } | |
1231 | ||
1232 | /* T is known constant value of virtual table pointer. Return BINFO of the | |
1233 | instance type. */ | |
1234 | ||
1235 | tree | |
1236 | vtable_pointer_value_to_binfo (tree t) | |
1237 | { | |
1238 | tree vtable; | |
1239 | unsigned HOST_WIDE_INT offset; | |
1240 | ||
1241 | if (!vtable_pointer_value_to_vtable (t, &vtable, &offset)) | |
1242 | return NULL_TREE; | |
1243 | ||
1244 | /* FIXME: for stores of construction vtables we return NULL, | |
1245 | because we do not have BINFO for those. Eventually we should fix | |
1246 | our representation to allow this case to be handled, too. | |
1247 | In the case we see store of BINFO we however may assume | |
1248 | that standard folding will be ale to cope with it. */ | |
1249 | return subbinfo_with_vtable_at_offset (TYPE_BINFO (DECL_CONTEXT (vtable)), | |
1250 | offset, vtable); | |
390675c8 JH |
1251 | } |
1252 | ||
5bccb77a JH |
1253 | /* Proudce polymorphic call context for call method of instance |
1254 | that is located within BASE (that is assumed to be a decl) at OFFSET. */ | |
1255 | ||
1256 | static void | |
1257 | get_polymorphic_call_info_for_decl (ipa_polymorphic_call_context *context, | |
1258 | tree base, HOST_WIDE_INT offset) | |
1259 | { | |
1260 | gcc_assert (DECL_P (base)); | |
1261 | ||
1262 | context->outer_type = TREE_TYPE (base); | |
1263 | context->offset = offset; | |
1264 | /* Make very conservative assumption that all objects | |
1265 | may be in construction. | |
1266 | TODO: ipa-prop already contains code to tell better. | |
1267 | merge it later. */ | |
1268 | context->maybe_in_construction = true; | |
1269 | context->maybe_derived_type = false; | |
1270 | } | |
1271 | ||
1272 | /* CST is an invariant (address of decl), try to get meaningful | |
1273 | polymorphic call context for polymorphic call of method | |
1274 | if instance of OTR_TYPE that is located at OFFSET of this invariant. | |
1275 | Return FALSE if nothing meaningful can be found. */ | |
1276 | ||
1277 | bool | |
1278 | get_polymorphic_call_info_from_invariant (ipa_polymorphic_call_context *context, | |
1279 | tree cst, | |
1280 | tree otr_type, | |
1281 | HOST_WIDE_INT offset) | |
1282 | { | |
1283 | HOST_WIDE_INT offset2, size, max_size; | |
1284 | tree base; | |
1285 | ||
1286 | if (TREE_CODE (cst) != ADDR_EXPR) | |
79c7de84 | 1287 | return false; |
5bccb77a JH |
1288 | |
1289 | cst = TREE_OPERAND (cst, 0); | |
1290 | base = get_ref_base_and_extent (cst, &offset2, &size, &max_size); | |
79c7de84 EB |
1291 | if (!DECL_P (base) || max_size == -1 || max_size != size) |
1292 | return false; | |
5bccb77a JH |
1293 | |
1294 | /* Only type inconsistent programs can have otr_type that is | |
1295 | not part of outer type. */ | |
79c7de84 EB |
1296 | if (!contains_type_p (TREE_TYPE (base), offset, otr_type)) |
1297 | return false; | |
5bccb77a | 1298 | |
79c7de84 | 1299 | get_polymorphic_call_info_for_decl (context, base, offset); |
5bccb77a JH |
1300 | return true; |
1301 | } | |
1302 | ||
68377e53 JH |
1303 | /* Given REF call in FNDECL, determine class of the polymorphic |
1304 | call (OTR_TYPE), its token (OTR_TOKEN) and CONTEXT. | |
1305 | Return pointer to object described by the context */ | |
1306 | ||
1307 | tree | |
1308 | get_polymorphic_call_info (tree fndecl, | |
1309 | tree ref, | |
1310 | tree *otr_type, | |
1311 | HOST_WIDE_INT *otr_token, | |
1312 | ipa_polymorphic_call_context *context) | |
1313 | { | |
1314 | tree base_pointer; | |
1315 | *otr_type = obj_type_ref_class (ref); | |
1316 | *otr_token = tree_to_uhwi (OBJ_TYPE_REF_TOKEN (ref)); | |
1317 | ||
1318 | /* Set up basic info in case we find nothing interesting in the analysis. */ | |
1319 | context->outer_type = *otr_type; | |
1320 | context->offset = 0; | |
1321 | base_pointer = OBJ_TYPE_REF_OBJECT (ref); | |
1322 | context->maybe_derived_type = true; | |
2d1644bf | 1323 | context->maybe_in_construction = true; |
68377e53 JH |
1324 | |
1325 | /* Walk SSA for outer object. */ | |
1326 | do | |
1327 | { | |
1328 | if (TREE_CODE (base_pointer) == SSA_NAME | |
1329 | && !SSA_NAME_IS_DEFAULT_DEF (base_pointer) | |
1330 | && SSA_NAME_DEF_STMT (base_pointer) | |
1331 | && gimple_assign_single_p (SSA_NAME_DEF_STMT (base_pointer))) | |
1332 | { | |
1333 | base_pointer = gimple_assign_rhs1 (SSA_NAME_DEF_STMT (base_pointer)); | |
1334 | STRIP_NOPS (base_pointer); | |
1335 | } | |
1336 | else if (TREE_CODE (base_pointer) == ADDR_EXPR) | |
1337 | { | |
1338 | HOST_WIDE_INT size, max_size; | |
1339 | HOST_WIDE_INT offset2; | |
1340 | tree base = get_ref_base_and_extent (TREE_OPERAND (base_pointer, 0), | |
1341 | &offset2, &size, &max_size); | |
1342 | ||
1343 | /* If this is a varying address, punt. */ | |
1344 | if ((TREE_CODE (base) == MEM_REF || DECL_P (base)) | |
1345 | && max_size != -1 | |
1346 | && max_size == size) | |
1347 | { | |
1348 | /* We found dereference of a pointer. Type of the pointer | |
1349 | and MEM_REF is meaningless, but we can look futher. */ | |
1350 | if (TREE_CODE (base) == MEM_REF) | |
1351 | { | |
1352 | base_pointer = TREE_OPERAND (base, 0); | |
1353 | context->offset | |
1354 | += offset2 + mem_ref_offset (base).low * BITS_PER_UNIT; | |
1355 | context->outer_type = NULL; | |
1356 | } | |
1357 | /* We found base object. In this case the outer_type | |
1358 | is known. */ | |
1359 | else if (DECL_P (base)) | |
1360 | { | |
7656ee72 | 1361 | gcc_assert (!POINTER_TYPE_P (TREE_TYPE (base))); |
68377e53 JH |
1362 | |
1363 | /* Only type inconsistent programs can have otr_type that is | |
1364 | not part of outer type. */ | |
7656ee72 JH |
1365 | if (!contains_type_p (TREE_TYPE (base), |
1366 | context->offset + offset2, *otr_type)) | |
3e86c6a8 JH |
1367 | { |
1368 | /* Use OTR_TOKEN = INT_MAX as a marker of probably type inconsistent | |
1369 | code sequences; we arrange the calls to be builtin_unreachable | |
1370 | later. */ | |
1371 | *otr_token = INT_MAX; | |
1372 | return base_pointer; | |
1373 | } | |
5bccb77a JH |
1374 | get_polymorphic_call_info_for_decl (context, base, |
1375 | context->offset + offset2); | |
7656ee72 | 1376 | return NULL; |
68377e53 JH |
1377 | } |
1378 | else | |
1379 | break; | |
1380 | } | |
1381 | else | |
1382 | break; | |
1383 | } | |
1384 | else if (TREE_CODE (base_pointer) == POINTER_PLUS_EXPR | |
1385 | && tree_fits_uhwi_p (TREE_OPERAND (base_pointer, 1))) | |
1386 | { | |
1387 | context->offset += tree_to_shwi (TREE_OPERAND (base_pointer, 1)) | |
1388 | * BITS_PER_UNIT; | |
1389 | base_pointer = TREE_OPERAND (base_pointer, 0); | |
1390 | } | |
1391 | else | |
1392 | break; | |
1393 | } | |
1394 | while (true); | |
1395 | ||
1396 | /* Try to determine type of the outer object. */ | |
1397 | if (TREE_CODE (base_pointer) == SSA_NAME | |
1398 | && SSA_NAME_IS_DEFAULT_DEF (base_pointer) | |
1399 | && TREE_CODE (SSA_NAME_VAR (base_pointer)) == PARM_DECL) | |
1400 | { | |
1401 | /* See if parameter is THIS pointer of a method. */ | |
1402 | if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE | |
1403 | && SSA_NAME_VAR (base_pointer) == DECL_ARGUMENTS (fndecl)) | |
1404 | { | |
1405 | context->outer_type = TREE_TYPE (TREE_TYPE (base_pointer)); | |
1406 | gcc_assert (TREE_CODE (context->outer_type) == RECORD_TYPE); | |
1407 | ||
1408 | /* Dynamic casting has possibly upcasted the type | |
1409 | in the hiearchy. In this case outer type is less | |
1410 | informative than inner type and we should forget | |
1411 | about it. */ | |
1412 | if (!contains_type_p (context->outer_type, context->offset, | |
1413 | *otr_type)) | |
1414 | { | |
1415 | context->outer_type = NULL; | |
1416 | return base_pointer; | |
1417 | } | |
1418 | ||
1419 | /* If the function is constructor or destructor, then | |
d74db8ff | 1420 | the type is possibly in construction, but we know |
68377e53 JH |
1421 | it is not derived type. */ |
1422 | if (DECL_CXX_CONSTRUCTOR_P (fndecl) | |
1423 | || DECL_CXX_DESTRUCTOR_P (fndecl)) | |
1424 | { | |
1425 | context->maybe_in_construction = true; | |
1426 | context->maybe_derived_type = false; | |
1427 | } | |
1428 | else | |
1429 | { | |
1430 | context->maybe_derived_type = true; | |
1431 | context->maybe_in_construction = false; | |
1432 | } | |
1433 | return base_pointer; | |
1434 | } | |
1435 | /* Non-PODs passed by value are really passed by invisible | |
1436 | reference. In this case we also know the type of the | |
1437 | object. */ | |
1438 | if (DECL_BY_REFERENCE (SSA_NAME_VAR (base_pointer))) | |
1439 | { | |
1440 | context->outer_type = TREE_TYPE (TREE_TYPE (base_pointer)); | |
1441 | gcc_assert (!POINTER_TYPE_P (context->outer_type)); | |
1442 | /* Only type inconsistent programs can have otr_type that is | |
1443 | not part of outer type. */ | |
1444 | if (!contains_type_p (context->outer_type, context->offset, | |
1445 | *otr_type)) | |
1446 | { | |
3e86c6a8 JH |
1447 | /* Use OTR_TOKEN = INT_MAX as a marker of probably type inconsistent |
1448 | code sequences; we arrange the calls to be builtin_unreachable | |
1449 | later. */ | |
1450 | *otr_token = INT_MAX; | |
68377e53 JH |
1451 | return base_pointer; |
1452 | } | |
1453 | context->maybe_derived_type = false; | |
1454 | context->maybe_in_construction = false; | |
1455 | return base_pointer; | |
1456 | } | |
1457 | } | |
1458 | /* TODO: There are multiple ways to derive a type. For instance | |
1459 | if BASE_POINTER is passed to an constructor call prior our refernece. | |
1460 | We do not make this type of flow sensitive analysis yet. */ | |
1461 | return base_pointer; | |
1462 | } | |
1463 | ||
1464 | /* Walk bases of OUTER_TYPE that contain OTR_TYPE at OFFSET. | |
1465 | Lookup their respecitve virtual methods for OTR_TOKEN and OTR_TYPE | |
1466 | and insert them to NODES. | |
1467 | ||
1468 | MATCHED_VTABLES and INSERTED is used to avoid duplicated work. */ | |
1469 | ||
1470 | static void | |
1471 | record_targets_from_bases (tree otr_type, | |
1472 | HOST_WIDE_INT otr_token, | |
1473 | tree outer_type, | |
1474 | HOST_WIDE_INT offset, | |
ec77d61f | 1475 | vec <cgraph_node *> &nodes, |
68377e53 JH |
1476 | pointer_set_t *inserted, |
1477 | pointer_set_t *matched_vtables, | |
1478 | bool *completep) | |
1479 | { | |
1480 | while (true) | |
1481 | { | |
1482 | HOST_WIDE_INT pos, size; | |
1483 | tree base_binfo; | |
1484 | tree fld; | |
1485 | ||
1486 | if (types_same_for_odr (outer_type, otr_type)) | |
1487 | return; | |
1488 | ||
1489 | for (fld = TYPE_FIELDS (outer_type); fld; fld = DECL_CHAIN (fld)) | |
1490 | { | |
1491 | if (TREE_CODE (fld) != FIELD_DECL) | |
1492 | continue; | |
1493 | ||
1494 | pos = int_bit_position (fld); | |
1495 | size = tree_to_shwi (DECL_SIZE (fld)); | |
ec77d61f JH |
1496 | if (pos <= offset && (pos + size) > offset |
1497 | /* Do not get confused by zero sized bases. */ | |
1498 | && polymorphic_type_binfo_p (TYPE_BINFO (TREE_TYPE (fld)))) | |
68377e53 JH |
1499 | break; |
1500 | } | |
1501 | /* Within a class type we should always find correcponding fields. */ | |
1502 | gcc_assert (fld && TREE_CODE (TREE_TYPE (fld)) == RECORD_TYPE); | |
1503 | ||
1504 | /* Nonbasetypes should have been stripped by outer_class_type. */ | |
1505 | gcc_assert (DECL_ARTIFICIAL (fld)); | |
1506 | ||
1507 | outer_type = TREE_TYPE (fld); | |
1508 | offset -= pos; | |
1509 | ||
1510 | base_binfo = get_binfo_at_offset (TYPE_BINFO (outer_type), | |
1511 | offset, otr_type); | |
ec77d61f JH |
1512 | if (!base_binfo) |
1513 | { | |
1514 | gcc_assert (odr_violation_reported); | |
1515 | return; | |
1516 | } | |
68377e53 JH |
1517 | gcc_assert (base_binfo); |
1518 | if (!pointer_set_insert (matched_vtables, BINFO_VTABLE (base_binfo))) | |
1519 | { | |
ec77d61f JH |
1520 | bool can_refer; |
1521 | tree target = gimple_get_virt_method_for_binfo (otr_token, | |
1522 | base_binfo, | |
1523 | &can_refer); | |
2d1644bf JH |
1524 | if (!target || ! DECL_CXX_DESTRUCTOR_P (target)) |
1525 | maybe_record_node (nodes, target, inserted, can_refer, completep); | |
68377e53 JH |
1526 | pointer_set_insert (matched_vtables, BINFO_VTABLE (base_binfo)); |
1527 | } | |
1528 | } | |
1529 | } | |
1530 | ||
3462aa02 JH |
1531 | /* When virtual table is removed, we may need to flush the cache. */ |
1532 | ||
1533 | static void | |
2c8326a5 | 1534 | devirt_variable_node_removal_hook (varpool_node *n, |
3462aa02 JH |
1535 | void *d ATTRIBUTE_UNUSED) |
1536 | { | |
1537 | if (cached_polymorphic_call_targets | |
67348ccc DM |
1538 | && DECL_VIRTUAL_P (n->decl) |
1539 | && type_in_anonymous_namespace_p (DECL_CONTEXT (n->decl))) | |
3462aa02 JH |
1540 | free_polymorphic_call_targets_hash (); |
1541 | } | |
1542 | ||
eefe9a99 | 1543 | /* Return vector containing possible targets of polymorphic call of type |
68377e53 JH |
1544 | OTR_TYPE caling method OTR_TOKEN within type of OTR_OUTER_TYPE and OFFSET. |
1545 | If INCLUDE_BASES is true, walk also base types of OUTER_TYPES containig | |
1546 | OTR_TYPE and include their virtual method. This is useful for types | |
1547 | possibly in construction or destruction where the virtual table may | |
1548 | temporarily change to one of base types. INCLUDE_DERIVER_TYPES make | |
1549 | us to walk the inheritance graph for all derivations. | |
1550 | ||
3e86c6a8 JH |
1551 | OTR_TOKEN == INT_MAX is used to mark calls that are provably |
1552 | undefined and should be redirected to unreachable. | |
1553 | ||
add5c763 | 1554 | If COMPLETEP is non-NULL, store true if the list is complete. |
eefe9a99 JH |
1555 | CACHE_TOKEN (if non-NULL) will get stored to an unique ID of entry |
1556 | in the target cache. If user needs to visit every target list | |
1557 | just once, it can memoize them. | |
1558 | ||
ec77d61f JH |
1559 | NONCONSTRUCTION_TARGETS specify number of targets with asumption that |
1560 | the type is not in the construction. Those targets appear first in the | |
1561 | vector returned. | |
1562 | ||
eefe9a99 JH |
1563 | Returned vector is placed into cache. It is NOT caller's responsibility |
1564 | to free it. The vector can be freed on cgraph_remove_node call if | |
1565 | the particular node is a virtual function present in the cache. */ | |
1566 | ||
1567 | vec <cgraph_node *> | |
1568 | possible_polymorphic_call_targets (tree otr_type, | |
1569 | HOST_WIDE_INT otr_token, | |
68377e53 JH |
1570 | ipa_polymorphic_call_context context, |
1571 | bool *completep, | |
ec77d61f JH |
1572 | void **cache_token, |
1573 | int *nonconstruction_targetsp) | |
eefe9a99 JH |
1574 | { |
1575 | static struct cgraph_node_hook_list *node_removal_hook_holder; | |
1576 | pointer_set_t *inserted; | |
1577 | pointer_set_t *matched_vtables; | |
add5c763 | 1578 | vec <cgraph_node *> nodes = vNULL; |
2d1644bf | 1579 | vec <tree> bases_to_consider = vNULL; |
68377e53 | 1580 | odr_type type, outer_type; |
eefe9a99 JH |
1581 | polymorphic_call_target_d key; |
1582 | polymorphic_call_target_d **slot; | |
1583 | unsigned int i; | |
1584 | tree binfo, target; | |
ec77d61f JH |
1585 | bool complete; |
1586 | bool can_refer; | |
2d1644bf | 1587 | bool skipped = false; |
eefe9a99 | 1588 | |
3e86c6a8 | 1589 | /* If ODR is not initialized, return empty incomplete list. */ |
79c7de84 EB |
1590 | if (!odr_hash.is_created ()) |
1591 | { | |
1592 | if (completep) | |
1593 | *completep = false; | |
ec77d61f JH |
1594 | if (nonconstruction_targetsp) |
1595 | *nonconstruction_targetsp = 0; | |
79c7de84 EB |
1596 | return nodes; |
1597 | } | |
add5c763 | 1598 | |
3e86c6a8 JH |
1599 | /* If we hit type inconsistency, just return empty list of targets. */ |
1600 | if (otr_token == INT_MAX) | |
1601 | { | |
1602 | if (completep) | |
1603 | *completep = true; | |
1604 | if (nonconstruction_targetsp) | |
1605 | *nonconstruction_targetsp = 0; | |
1606 | return nodes; | |
1607 | } | |
1608 | ||
68377e53 | 1609 | type = get_odr_type (otr_type, true); |
eefe9a99 | 1610 | |
68377e53 | 1611 | /* Lookup the outer class type we want to walk. */ |
3e86c6a8 JH |
1612 | if (context.outer_type |
1613 | && !get_class_context (&context, otr_type)) | |
1614 | { | |
1615 | if (completep) | |
1616 | *completep = false; | |
1617 | if (nonconstruction_targetsp) | |
1618 | *nonconstruction_targetsp = 0; | |
1619 | return nodes; | |
1620 | } | |
eefe9a99 | 1621 | |
79c7de84 | 1622 | /* We canonicalize our query, so we do not need extra hashtable entries. */ |
68377e53 JH |
1623 | |
1624 | /* Without outer type, we have no use for offset. Just do the | |
1625 | basic search from innter type */ | |
1626 | if (!context.outer_type) | |
1627 | { | |
1628 | context.outer_type = otr_type; | |
1629 | context.offset = 0; | |
1630 | } | |
1631 | /* We need to update our hiearchy if the type does not exist. */ | |
1632 | outer_type = get_odr_type (context.outer_type, true); | |
ec77d61f | 1633 | /* If the type is complete, there are no derivations. */ |
68377e53 JH |
1634 | if (TYPE_FINAL_P (outer_type->type)) |
1635 | context.maybe_derived_type = false; | |
eefe9a99 JH |
1636 | |
1637 | /* Initialize query cache. */ | |
1638 | if (!cached_polymorphic_call_targets) | |
1639 | { | |
1640 | cached_polymorphic_call_targets = pointer_set_create (); | |
1641 | polymorphic_call_target_hash.create (23); | |
1642 | if (!node_removal_hook_holder) | |
3462aa02 JH |
1643 | { |
1644 | node_removal_hook_holder = | |
1645 | cgraph_add_node_removal_hook (&devirt_node_removal_hook, NULL); | |
1646 | varpool_add_node_removal_hook (&devirt_variable_node_removal_hook, | |
1647 | NULL); | |
1648 | } | |
eefe9a99 JH |
1649 | } |
1650 | ||
1651 | /* Lookup cached answer. */ | |
1652 | key.type = type; | |
1653 | key.otr_token = otr_token; | |
68377e53 | 1654 | key.context = context; |
eefe9a99 JH |
1655 | slot = polymorphic_call_target_hash.find_slot (&key, INSERT); |
1656 | if (cache_token) | |
1657 | *cache_token = (void *)*slot; | |
1658 | if (*slot) | |
68377e53 JH |
1659 | { |
1660 | if (completep) | |
ec77d61f JH |
1661 | *completep = (*slot)->complete; |
1662 | if (nonconstruction_targetsp) | |
1663 | *nonconstruction_targetsp = (*slot)->nonconstruction_targets; | |
68377e53 JH |
1664 | return (*slot)->targets; |
1665 | } | |
1666 | ||
ec77d61f | 1667 | complete = true; |
eefe9a99 JH |
1668 | |
1669 | /* Do actual search. */ | |
1670 | timevar_push (TV_IPA_VIRTUAL_CALL); | |
1671 | *slot = XCNEW (polymorphic_call_target_d); | |
1672 | if (cache_token) | |
68377e53 | 1673 | *cache_token = (void *)*slot; |
eefe9a99 JH |
1674 | (*slot)->type = type; |
1675 | (*slot)->otr_token = otr_token; | |
68377e53 | 1676 | (*slot)->context = context; |
eefe9a99 JH |
1677 | |
1678 | inserted = pointer_set_create (); | |
1679 | matched_vtables = pointer_set_create (); | |
1680 | ||
1681 | /* First see virtual method of type itself. */ | |
68377e53 JH |
1682 | binfo = get_binfo_at_offset (TYPE_BINFO (outer_type->type), |
1683 | context.offset, otr_type); | |
ec77d61f JH |
1684 | if (binfo) |
1685 | target = gimple_get_virt_method_for_binfo (otr_token, binfo, | |
1686 | &can_refer); | |
1687 | else | |
68377e53 | 1688 | { |
ec77d61f JH |
1689 | gcc_assert (odr_violation_reported); |
1690 | target = NULL; | |
1691 | } | |
68377e53 | 1692 | |
2d1644bf JH |
1693 | /* Destructors are never called through construction virtual tables, |
1694 | because the type is always known. */ | |
1695 | if (target && DECL_CXX_DESTRUCTOR_P (target)) | |
1696 | context.maybe_in_construction = false; | |
ec77d61f JH |
1697 | |
1698 | if (target) | |
1699 | { | |
1700 | /* In the case we get complete method, we don't need | |
68377e53 JH |
1701 | to walk derivations. */ |
1702 | if (DECL_FINAL_P (target)) | |
1703 | context.maybe_derived_type = false; | |
1704 | } | |
2d1644bf JH |
1705 | |
1706 | /* If OUTER_TYPE is abstract, we know we are not seeing its instance. */ | |
1707 | if (type_possibly_instantiated_p (outer_type->type)) | |
1708 | maybe_record_node (nodes, target, inserted, can_refer, &complete); | |
ec77d61f | 1709 | else |
2d1644bf JH |
1710 | { |
1711 | skipped = true; | |
1712 | gcc_assert (in_lto_p || context.maybe_derived_type); | |
1713 | } | |
79c7de84 | 1714 | |
eefe9a99 JH |
1715 | pointer_set_insert (matched_vtables, BINFO_VTABLE (binfo)); |
1716 | ||
ec77d61f | 1717 | /* Next walk recursively all derived types. */ |
68377e53 JH |
1718 | if (context.maybe_derived_type) |
1719 | { | |
1720 | /* For anonymous namespace types we can attempt to build full type. | |
1721 | All derivations must be in this unit (unless we see partial unit). */ | |
2d1644bf | 1722 | if (!type->all_derivations_known) |
ec77d61f | 1723 | complete = false; |
68377e53 JH |
1724 | for (i = 0; i < outer_type->derived_types.length(); i++) |
1725 | possible_polymorphic_call_targets_1 (nodes, inserted, | |
1726 | matched_vtables, | |
79c7de84 EB |
1727 | otr_type, |
1728 | outer_type->derived_types[i], | |
68377e53 | 1729 | otr_token, outer_type->type, |
2d1644bf JH |
1730 | context.offset, &complete, |
1731 | bases_to_consider, | |
1732 | context.maybe_in_construction); | |
68377e53 | 1733 | } |
79c7de84 | 1734 | |
ec77d61f JH |
1735 | /* Finally walk bases, if asked to. */ |
1736 | (*slot)->nonconstruction_targets = nodes.length(); | |
2d1644bf JH |
1737 | |
1738 | /* Destructors are never called through construction virtual tables, | |
1739 | because the type is always known. One of entries may be cxa_pure_virtual | |
1740 | so look to at least two of them. */ | |
1741 | if (context.maybe_in_construction) | |
1742 | for (i =0 ; i < MIN (nodes.length (), 2); i++) | |
1743 | if (DECL_CXX_DESTRUCTOR_P (nodes[i]->decl)) | |
1744 | context.maybe_in_construction = false; | |
ec77d61f | 1745 | if (context.maybe_in_construction) |
2d1644bf JH |
1746 | { |
1747 | if (type != outer_type | |
1748 | && (!skipped | |
1749 | || (context.maybe_derived_type | |
1750 | && !type_all_derivations_known_p (outer_type->type)))) | |
1751 | record_targets_from_bases (otr_type, otr_token, outer_type->type, | |
1752 | context.offset, nodes, inserted, | |
1753 | matched_vtables, &complete); | |
1754 | if (skipped) | |
1755 | maybe_record_node (nodes, target, inserted, can_refer, &complete); | |
1756 | for (i = 0; i < bases_to_consider.length(); i++) | |
1757 | maybe_record_node (nodes, bases_to_consider[i], inserted, can_refer, &complete); | |
1758 | } | |
1759 | bases_to_consider.release(); | |
ec77d61f | 1760 | |
eefe9a99 | 1761 | (*slot)->targets = nodes; |
ec77d61f | 1762 | (*slot)->complete = complete; |
68377e53 | 1763 | if (completep) |
ec77d61f JH |
1764 | *completep = complete; |
1765 | if (nonconstruction_targetsp) | |
1766 | *nonconstruction_targetsp = (*slot)->nonconstruction_targets; | |
eefe9a99 JH |
1767 | |
1768 | pointer_set_destroy (inserted); | |
1769 | pointer_set_destroy (matched_vtables); | |
1770 | timevar_pop (TV_IPA_VIRTUAL_CALL); | |
1771 | return nodes; | |
1772 | } | |
1773 | ||
1774 | /* Dump all possible targets of a polymorphic call. */ | |
1775 | ||
1776 | void | |
1777 | dump_possible_polymorphic_call_targets (FILE *f, | |
68377e53 JH |
1778 | tree otr_type, |
1779 | HOST_WIDE_INT otr_token, | |
1780 | const ipa_polymorphic_call_context &ctx) | |
eefe9a99 JH |
1781 | { |
1782 | vec <cgraph_node *> targets; | |
1783 | bool final; | |
1784 | odr_type type = get_odr_type (otr_type, false); | |
1785 | unsigned int i; | |
ec77d61f | 1786 | int nonconstruction; |
eefe9a99 JH |
1787 | |
1788 | if (!type) | |
1789 | return; | |
1790 | targets = possible_polymorphic_call_targets (otr_type, otr_token, | |
68377e53 | 1791 | ctx, |
ec77d61f | 1792 | &final, NULL, &nonconstruction); |
68377e53 | 1793 | fprintf (f, " Targets of polymorphic call of type %i:", type->id); |
eefe9a99 | 1794 | print_generic_expr (f, type->type, TDF_SLIM); |
ec77d61f JH |
1795 | fprintf (f, " token %i\n", (int)otr_token); |
1796 | if (ctx.outer_type || ctx.offset) | |
1797 | { | |
1798 | fprintf (f, " Contained in type:"); | |
1799 | print_generic_expr (f, ctx.outer_type, TDF_SLIM); | |
1800 | fprintf (f, " at offset "HOST_WIDE_INT_PRINT_DEC"\n", | |
1801 | ctx.offset); | |
1802 | } | |
1803 | ||
1804 | fprintf (f, " %s%s%s\n ", | |
1805 | final ? "This is a complete list." : | |
68377e53 JH |
1806 | "This is partial list; extra targets may be defined in other units.", |
1807 | ctx.maybe_in_construction ? " (base types included)" : "", | |
1808 | ctx.maybe_derived_type ? " (derived types included)" : ""); | |
eefe9a99 | 1809 | for (i = 0; i < targets.length (); i++) |
ec77d61f JH |
1810 | { |
1811 | char *name = NULL; | |
1812 | if (i == (unsigned)nonconstruction) | |
1813 | fprintf (f, "\n If the type is in construction," | |
1814 | " then additional tarets are:\n" | |
1815 | " "); | |
1816 | if (in_lto_p) | |
1817 | name = cplus_demangle_v3 (targets[i]->asm_name (), 0); | |
1818 | fprintf (f, " %s/%i", name ? name : targets[i]->name (), targets[i]->order); | |
1819 | if (in_lto_p) | |
1820 | free (name); | |
1821 | if (!targets[i]->definition) | |
1822 | fprintf (f, " (no definition%s)", | |
1823 | DECL_DECLARED_INLINE_P (targets[i]->decl) | |
1824 | ? " inline" : ""); | |
1825 | } | |
68377e53 | 1826 | fprintf (f, "\n\n"); |
eefe9a99 JH |
1827 | } |
1828 | ||
0e1474e5 JH |
1829 | |
1830 | /* Return true if N can be possibly target of a polymorphic call of | |
1831 | OTR_TYPE/OTR_TOKEN. */ | |
1832 | ||
1833 | bool | |
1834 | possible_polymorphic_call_target_p (tree otr_type, | |
1835 | HOST_WIDE_INT otr_token, | |
68377e53 | 1836 | const ipa_polymorphic_call_context &ctx, |
0e1474e5 JH |
1837 | struct cgraph_node *n) |
1838 | { | |
1839 | vec <cgraph_node *> targets; | |
1840 | unsigned int i; | |
68377e53 | 1841 | enum built_in_function fcode; |
450ad0cd | 1842 | bool final; |
0e1474e5 | 1843 | |
68377e53 JH |
1844 | if (TREE_CODE (TREE_TYPE (n->decl)) == FUNCTION_TYPE |
1845 | && ((fcode = DECL_FUNCTION_CODE (n->decl)) | |
1846 | == BUILT_IN_UNREACHABLE | |
1847 | || fcode == BUILT_IN_TRAP)) | |
1848 | return true; | |
1849 | ||
0e1474e5 JH |
1850 | if (!odr_hash.is_created ()) |
1851 | return true; | |
68377e53 | 1852 | targets = possible_polymorphic_call_targets (otr_type, otr_token, ctx, &final); |
0e1474e5 | 1853 | for (i = 0; i < targets.length (); i++) |
68377e53 | 1854 | if (symtab_semantically_equivalent_p (n, targets[i])) |
0e1474e5 | 1855 | return true; |
450ad0cd JH |
1856 | |
1857 | /* At a moment we allow middle end to dig out new external declarations | |
1858 | as a targets of polymorphic calls. */ | |
67348ccc | 1859 | if (!final && !n->definition) |
450ad0cd | 1860 | return true; |
0e1474e5 JH |
1861 | return false; |
1862 | } | |
1863 | ||
1864 | ||
1865 | /* After callgraph construction new external nodes may appear. | |
1866 | Add them into the graph. */ | |
1867 | ||
1868 | void | |
1869 | update_type_inheritance_graph (void) | |
1870 | { | |
1871 | struct cgraph_node *n; | |
1872 | ||
1873 | if (!odr_hash.is_created ()) | |
1874 | return; | |
1875 | free_polymorphic_call_targets_hash (); | |
1876 | timevar_push (TV_IPA_INHERITANCE); | |
68377e53 | 1877 | /* We reconstruct the graph starting from types of all methods seen in the |
0e1474e5 JH |
1878 | the unit. */ |
1879 | FOR_EACH_FUNCTION (n) | |
67348ccc DM |
1880 | if (DECL_VIRTUAL_P (n->decl) |
1881 | && !n->definition | |
1882 | && symtab_real_symbol_p (n)) | |
1883 | get_odr_type (method_class_type (TREE_TYPE (n->decl)), true); | |
0e1474e5 JH |
1884 | timevar_pop (TV_IPA_INHERITANCE); |
1885 | } | |
bbc9396b JH |
1886 | |
1887 | ||
1888 | /* Return true if N looks like likely target of a polymorphic call. | |
1889 | Rule out cxa_pure_virtual, noreturns, function declared cold and | |
1890 | other obvious cases. */ | |
1891 | ||
1892 | bool | |
1893 | likely_target_p (struct cgraph_node *n) | |
1894 | { | |
1895 | int flags; | |
1896 | /* cxa_pure_virtual and similar things are not likely. */ | |
67348ccc | 1897 | if (TREE_CODE (TREE_TYPE (n->decl)) != METHOD_TYPE) |
bbc9396b | 1898 | return false; |
67348ccc | 1899 | flags = flags_from_decl_or_type (n->decl); |
bbc9396b JH |
1900 | if (flags & ECF_NORETURN) |
1901 | return false; | |
1902 | if (lookup_attribute ("cold", | |
67348ccc | 1903 | DECL_ATTRIBUTES (n->decl))) |
bbc9396b JH |
1904 | return false; |
1905 | if (n->frequency < NODE_FREQUENCY_NORMAL) | |
1906 | return false; | |
ccb05ef2 JH |
1907 | /* If there are no virtual tables refering the target alive, |
1908 | the only way the target can be called is an instance comming from other | |
1909 | compilation unit; speculative devirtualization is build around an | |
1910 | assumption that won't happen. */ | |
1911 | if (!referenced_from_vtable_p (n)) | |
1912 | return false; | |
bbc9396b JH |
1913 | return true; |
1914 | } | |
1915 | ||
1916 | /* The ipa-devirt pass. | |
3462aa02 JH |
1917 | When polymorphic call has only one likely target in the unit, |
1918 | turn it into speculative call. */ | |
bbc9396b JH |
1919 | |
1920 | static unsigned int | |
1921 | ipa_devirt (void) | |
1922 | { | |
1923 | struct cgraph_node *n; | |
1924 | struct pointer_set_t *bad_call_targets = pointer_set_create (); | |
1925 | struct cgraph_edge *e; | |
1926 | ||
1927 | int npolymorphic = 0, nspeculated = 0, nconverted = 0, ncold = 0; | |
1928 | int nmultiple = 0, noverwritable = 0, ndevirtualized = 0, nnotdefined = 0; | |
570215f9 | 1929 | int nwrong = 0, nok = 0, nexternal = 0, nartificial = 0; |
bbc9396b JH |
1930 | |
1931 | FOR_EACH_DEFINED_FUNCTION (n) | |
1932 | { | |
1933 | bool update = false; | |
1934 | if (dump_file && n->indirect_calls) | |
1935 | fprintf (dump_file, "\n\nProcesing function %s/%i\n", | |
fec39fa6 | 1936 | n->name (), n->order); |
bbc9396b JH |
1937 | for (e = n->indirect_calls; e; e = e->next_callee) |
1938 | if (e->indirect_info->polymorphic) | |
1939 | { | |
1940 | struct cgraph_node *likely_target = NULL; | |
1941 | void *cache_token; | |
1942 | bool final; | |
ec77d61f | 1943 | int nonconstruction_targets; |
bbc9396b JH |
1944 | vec <cgraph_node *>targets |
1945 | = possible_polymorphic_call_targets | |
ec77d61f | 1946 | (e, &final, &cache_token, &nonconstruction_targets); |
bbc9396b JH |
1947 | unsigned int i; |
1948 | ||
1949 | if (dump_file) | |
1950 | dump_possible_polymorphic_call_targets | |
1951 | (dump_file, e); | |
3462aa02 | 1952 | |
bbc9396b JH |
1953 | npolymorphic++; |
1954 | ||
bbc9396b JH |
1955 | if (!cgraph_maybe_hot_edge_p (e)) |
1956 | { | |
1957 | if (dump_file) | |
ec77d61f | 1958 | fprintf (dump_file, "Call is cold\n\n"); |
bbc9396b JH |
1959 | ncold++; |
1960 | continue; | |
1961 | } | |
1962 | if (e->speculative) | |
1963 | { | |
1964 | if (dump_file) | |
ec77d61f | 1965 | fprintf (dump_file, "Call is aready speculated\n\n"); |
bbc9396b JH |
1966 | nspeculated++; |
1967 | ||
1968 | /* When dumping see if we agree with speculation. */ | |
1969 | if (!dump_file) | |
1970 | continue; | |
1971 | } | |
1972 | if (pointer_set_contains (bad_call_targets, | |
1973 | cache_token)) | |
1974 | { | |
1975 | if (dump_file) | |
ec77d61f | 1976 | fprintf (dump_file, "Target list is known to be useless\n\n"); |
bbc9396b JH |
1977 | nmultiple++; |
1978 | continue; | |
1979 | } | |
c3284718 | 1980 | for (i = 0; i < targets.length (); i++) |
bbc9396b JH |
1981 | if (likely_target_p (targets[i])) |
1982 | { | |
1983 | if (likely_target) | |
1984 | { | |
ec77d61f JH |
1985 | if (i < (unsigned) nonconstruction_targets) |
1986 | { | |
1987 | likely_target = NULL; | |
1988 | if (dump_file) | |
1989 | fprintf (dump_file, "More than one likely target\n\n"); | |
1990 | nmultiple++; | |
1991 | } | |
bbc9396b JH |
1992 | break; |
1993 | } | |
1994 | likely_target = targets[i]; | |
1995 | } | |
1996 | if (!likely_target) | |
1997 | { | |
1998 | pointer_set_insert (bad_call_targets, cache_token); | |
1999 | continue; | |
2000 | } | |
2001 | /* This is reached only when dumping; check if we agree or disagree | |
2002 | with the speculation. */ | |
2003 | if (e->speculative) | |
2004 | { | |
2005 | struct cgraph_edge *e2; | |
2006 | struct ipa_ref *ref; | |
2007 | cgraph_speculative_call_info (e, e2, e, ref); | |
2008 | if (cgraph_function_or_thunk_node (e2->callee, NULL) | |
2009 | == cgraph_function_or_thunk_node (likely_target, NULL)) | |
2010 | { | |
ec77d61f | 2011 | fprintf (dump_file, "We agree with speculation\n\n"); |
bbc9396b JH |
2012 | nok++; |
2013 | } | |
2014 | else | |
2015 | { | |
ec77d61f | 2016 | fprintf (dump_file, "We disagree with speculation\n\n"); |
bbc9396b JH |
2017 | nwrong++; |
2018 | } | |
2019 | continue; | |
2020 | } | |
67348ccc | 2021 | if (!likely_target->definition) |
bbc9396b JH |
2022 | { |
2023 | if (dump_file) | |
ec77d61f | 2024 | fprintf (dump_file, "Target is not an definition\n\n"); |
bbc9396b JH |
2025 | nnotdefined++; |
2026 | continue; | |
2027 | } | |
2028 | /* Do not introduce new references to external symbols. While we | |
2029 | can handle these just well, it is common for programs to | |
2030 | incorrectly with headers defining methods they are linked | |
2031 | with. */ | |
67348ccc | 2032 | if (DECL_EXTERNAL (likely_target->decl)) |
bbc9396b JH |
2033 | { |
2034 | if (dump_file) | |
ec77d61f | 2035 | fprintf (dump_file, "Target is external\n\n"); |
bbc9396b JH |
2036 | nexternal++; |
2037 | continue; | |
2038 | } | |
570215f9 JM |
2039 | /* Don't use an implicitly-declared destructor (c++/58678). */ |
2040 | struct cgraph_node *non_thunk_target | |
2041 | = cgraph_function_node (likely_target); | |
2042 | if (DECL_ARTIFICIAL (non_thunk_target->decl) | |
2043 | && DECL_COMDAT (non_thunk_target->decl)) | |
2044 | { | |
2045 | if (dump_file) | |
2046 | fprintf (dump_file, "Target is artificial\n\n"); | |
2047 | nartificial++; | |
2048 | continue; | |
2049 | } | |
bbc9396b JH |
2050 | if (cgraph_function_body_availability (likely_target) |
2051 | <= AVAIL_OVERWRITABLE | |
67348ccc | 2052 | && symtab_can_be_discarded (likely_target)) |
bbc9396b JH |
2053 | { |
2054 | if (dump_file) | |
ec77d61f | 2055 | fprintf (dump_file, "Target is overwritable\n\n"); |
bbc9396b JH |
2056 | noverwritable++; |
2057 | continue; | |
2058 | } | |
2059 | else | |
2060 | { | |
2061 | if (dump_file) | |
2062 | fprintf (dump_file, | |
ec77d61f | 2063 | "Speculatively devirtualizing call in %s/%i to %s/%i\n\n", |
fec39fa6 TS |
2064 | n->name (), n->order, |
2065 | likely_target->name (), | |
67348ccc DM |
2066 | likely_target->order); |
2067 | if (!symtab_can_be_discarded (likely_target)) | |
5b79657a JH |
2068 | { |
2069 | cgraph_node *alias; | |
2070 | alias = cgraph (symtab_nonoverwritable_alias | |
67348ccc | 2071 | (likely_target)); |
5b79657a JH |
2072 | if (alias) |
2073 | likely_target = alias; | |
2074 | } | |
bbc9396b JH |
2075 | nconverted++; |
2076 | update = true; | |
2077 | cgraph_turn_edge_to_speculative | |
2078 | (e, likely_target, e->count * 8 / 10, e->frequency * 8 / 10); | |
2079 | } | |
2080 | } | |
2081 | if (update) | |
2082 | inline_update_overall_summary (n); | |
2083 | } | |
2084 | pointer_set_destroy (bad_call_targets); | |
2085 | ||
2086 | if (dump_file) | |
2087 | fprintf (dump_file, | |
2088 | "%i polymorphic calls, %i devirtualized," | |
2089 | " %i speculatively devirtualized, %i cold\n" | |
2090 | "%i have multiple targets, %i overwritable," | |
2091 | " %i already speculated (%i agree, %i disagree)," | |
570215f9 | 2092 | " %i external, %i not defined, %i artificial\n", |
bbc9396b JH |
2093 | npolymorphic, ndevirtualized, nconverted, ncold, |
2094 | nmultiple, noverwritable, nspeculated, nok, nwrong, | |
570215f9 | 2095 | nexternal, nnotdefined, nartificial); |
bbc9396b JH |
2096 | return ndevirtualized ? TODO_remove_functions : 0; |
2097 | } | |
2098 | ||
bbc9396b JH |
2099 | namespace { |
2100 | ||
2101 | const pass_data pass_data_ipa_devirt = | |
2102 | { | |
2103 | IPA_PASS, /* type */ | |
2104 | "devirt", /* name */ | |
2105 | OPTGROUP_NONE, /* optinfo_flags */ | |
bbc9396b JH |
2106 | true, /* has_execute */ |
2107 | TV_IPA_DEVIRT, /* tv_id */ | |
2108 | 0, /* properties_required */ | |
2109 | 0, /* properties_provided */ | |
2110 | 0, /* properties_destroyed */ | |
2111 | 0, /* todo_flags_start */ | |
2112 | ( TODO_dump_symtab ), /* todo_flags_finish */ | |
2113 | }; | |
2114 | ||
2115 | class pass_ipa_devirt : public ipa_opt_pass_d | |
2116 | { | |
2117 | public: | |
c3284718 RS |
2118 | pass_ipa_devirt (gcc::context *ctxt) |
2119 | : ipa_opt_pass_d (pass_data_ipa_devirt, ctxt, | |
2120 | NULL, /* generate_summary */ | |
2121 | NULL, /* write_summary */ | |
2122 | NULL, /* read_summary */ | |
2123 | NULL, /* write_optimization_summary */ | |
2124 | NULL, /* read_optimization_summary */ | |
2125 | NULL, /* stmt_fixup */ | |
2126 | 0, /* function_transform_todo_flags_start */ | |
2127 | NULL, /* function_transform */ | |
2128 | NULL) /* variable_transform */ | |
bbc9396b JH |
2129 | {} |
2130 | ||
2131 | /* opt_pass methods: */ | |
1a3d085c TS |
2132 | virtual bool gate (function *) |
2133 | { | |
2134 | return (flag_devirtualize | |
2135 | && flag_devirtualize_speculatively | |
2136 | && optimize); | |
2137 | } | |
2138 | ||
bbc9396b JH |
2139 | unsigned int execute () { return ipa_devirt (); } |
2140 | ||
2141 | }; // class pass_ipa_devirt | |
2142 | ||
2143 | } // anon namespace | |
2144 | ||
2145 | ipa_opt_pass_d * | |
2146 | make_pass_ipa_devirt (gcc::context *ctxt) | |
2147 | { | |
2148 | return new pass_ipa_devirt (ctxt); | |
2149 | } | |
2150 | ||
eefe9a99 | 2151 | #include "gt-ipa-devirt.h" |