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aa803cc7 | 1 | /* Analysis of polymorphic call context. |
5624e564 | 2 | Copyright (C) 2013-2015 Free Software Foundation, Inc. |
aa803cc7 JH |
3 | Contributed by Jan Hubicka |
4 | ||
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it under | |
8 | the terms of the GNU General Public License as published by the Free | |
9 | Software Foundation; either version 3, or (at your option) any later | |
10 | version. | |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GCC; see the file COPYING3. If not see | |
19 | <http://www.gnu.org/licenses/>. */ | |
20 | ||
21 | #include "config.h" | |
22 | #include "system.h" | |
23 | #include "coretypes.h" | |
24 | #include "tm.h" | |
40e23961 MC |
25 | #include "hash-set.h" |
26 | #include "machmode.h" | |
27 | #include "vec.h" | |
28 | #include "double-int.h" | |
29 | #include "input.h" | |
30 | #include "alias.h" | |
31 | #include "symtab.h" | |
32 | #include "wide-int.h" | |
33 | #include "inchash.h" | |
aa803cc7 | 34 | #include "tree.h" |
40e23961 | 35 | #include "fold-const.h" |
aa803cc7 JH |
36 | #include "print-tree.h" |
37 | #include "calls.h" | |
36566b39 PK |
38 | #include "hashtab.h" |
39 | #include "hard-reg-set.h" | |
40 | #include "function.h" | |
41 | #include "rtl.h" | |
42 | #include "flags.h" | |
43 | #include "statistics.h" | |
44 | #include "real.h" | |
45 | #include "fixed-value.h" | |
46 | #include "insn-config.h" | |
47 | #include "expmed.h" | |
48 | #include "dojump.h" | |
49 | #include "explow.h" | |
50 | #include "emit-rtl.h" | |
51 | #include "varasm.h" | |
52 | #include "stmt.h" | |
aa803cc7 JH |
53 | #include "expr.h" |
54 | #include "tree-pass.h" | |
aa803cc7 | 55 | #include "target.h" |
aa803cc7 | 56 | #include "tree-pretty-print.h" |
60393bbc AM |
57 | #include "predict.h" |
58 | #include "basic-block.h" | |
c582198b AM |
59 | #include "hash-map.h" |
60 | #include "is-a.h" | |
61 | #include "plugin-api.h" | |
c582198b AM |
62 | #include "ipa-ref.h" |
63 | #include "cgraph.h" | |
aa803cc7 JH |
64 | #include "ipa-utils.h" |
65 | #include "tree-ssa-alias.h" | |
66 | #include "internal-fn.h" | |
67 | #include "gimple-fold.h" | |
68 | #include "gimple-expr.h" | |
69 | #include "gimple.h" | |
c582198b | 70 | #include "alloc-pool.h" |
dd912cb8 | 71 | #include "symbol-summary.h" |
c582198b | 72 | #include "ipa-prop.h" |
aa803cc7 JH |
73 | #include "ipa-inline.h" |
74 | #include "diagnostic.h" | |
75 | #include "tree-dfa.h" | |
76 | #include "demangle.h" | |
77 | #include "dbgcnt.h" | |
78 | #include "gimple-pretty-print.h" | |
79 | #include "stor-layout.h" | |
80 | #include "intl.h" | |
81 | #include "data-streamer.h" | |
82 | #include "lto-streamer.h" | |
83 | #include "streamer-hooks.h" | |
b3406fa0 RB |
84 | #include "tree-ssa-operands.h" |
85 | #include "tree-into-ssa.h" | |
aa803cc7 JH |
86 | |
87 | /* Return true when TYPE contains an polymorphic type and thus is interesting | |
88 | for devirtualization machinery. */ | |
89 | ||
67a1b94c JH |
90 | static bool contains_type_p (tree, HOST_WIDE_INT, tree, |
91 | bool consider_placement_new = true, | |
92 | bool consider_bases = true); | |
aa803cc7 JH |
93 | |
94 | bool | |
95 | contains_polymorphic_type_p (const_tree type) | |
96 | { | |
97 | type = TYPE_MAIN_VARIANT (type); | |
98 | ||
99 | if (RECORD_OR_UNION_TYPE_P (type)) | |
100 | { | |
101 | if (TYPE_BINFO (type) | |
102 | && polymorphic_type_binfo_p (TYPE_BINFO (type))) | |
103 | return true; | |
104 | for (tree fld = TYPE_FIELDS (type); fld; fld = DECL_CHAIN (fld)) | |
105 | if (TREE_CODE (fld) == FIELD_DECL | |
106 | && !DECL_ARTIFICIAL (fld) | |
107 | && contains_polymorphic_type_p (TREE_TYPE (fld))) | |
108 | return true; | |
109 | return false; | |
110 | } | |
111 | if (TREE_CODE (type) == ARRAY_TYPE) | |
112 | return contains_polymorphic_type_p (TREE_TYPE (type)); | |
113 | return false; | |
114 | } | |
115 | ||
116 | /* Return true if it seems valid to use placement new to build EXPECTED_TYPE | |
117 | at possition CUR_OFFSET within TYPE. | |
118 | ||
119 | POD can be changed to an instance of a polymorphic type by | |
120 | placement new. Here we play safe and assume that any | |
121 | non-polymorphic type is POD. */ | |
122 | bool | |
123 | possible_placement_new (tree type, tree expected_type, | |
124 | HOST_WIDE_INT cur_offset) | |
125 | { | |
126 | return ((TREE_CODE (type) != RECORD_TYPE | |
127 | || !TYPE_BINFO (type) | |
e8864c85 | 128 | || cur_offset >= POINTER_SIZE |
aa803cc7 JH |
129 | || !polymorphic_type_binfo_p (TYPE_BINFO (type))) |
130 | && (!TYPE_SIZE (type) | |
131 | || !tree_fits_shwi_p (TYPE_SIZE (type)) | |
132 | || (cur_offset | |
133 | + (expected_type ? tree_to_uhwi (TYPE_SIZE (expected_type)) | |
b30df7b6 | 134 | : POINTER_SIZE) |
aa803cc7 JH |
135 | <= tree_to_uhwi (TYPE_SIZE (type))))); |
136 | } | |
137 | ||
67a1b94c | 138 | /* THIS->OUTER_TYPE is a type of memory object where object of OTR_TYPE |
aa803cc7 JH |
139 | is contained at THIS->OFFSET. Walk the memory representation of |
140 | THIS->OUTER_TYPE and find the outermost class type that match | |
67a1b94c | 141 | OTR_TYPE or contain OTR_TYPE as a base. Update THIS |
aa803cc7 JH |
142 | to represent it. |
143 | ||
67a1b94c | 144 | If OTR_TYPE is NULL, just find outermost polymorphic type with |
aa803cc7 JH |
145 | virtual table present at possition OFFSET. |
146 | ||
147 | For example when THIS represents type | |
148 | class A | |
149 | { | |
150 | int a; | |
151 | class B b; | |
152 | } | |
153 | and we look for type at offset sizeof(int), we end up with B and offset 0. | |
154 | If the same is produced by multiple inheritance, we end up with A and offset | |
155 | sizeof(int). | |
156 | ||
157 | If we can not find corresponding class, give up by setting | |
67a1b94c JH |
158 | THIS->OUTER_TYPE to OTR_TYPE and THIS->OFFSET to NULL. |
159 | Return true when lookup was sucesful. | |
160 | ||
161 | When CONSIDER_PLACEMENT_NEW is false, reject contexts that may be made | |
162 | valid only via alocation of new polymorphic type inside by means | |
163 | of placement new. | |
164 | ||
165 | When CONSIDER_BASES is false, only look for actual fields, not base types | |
166 | of TYPE. */ | |
aa803cc7 JH |
167 | |
168 | bool | |
67a1b94c JH |
169 | ipa_polymorphic_call_context::restrict_to_inner_class (tree otr_type, |
170 | bool consider_placement_new, | |
171 | bool consider_bases) | |
aa803cc7 JH |
172 | { |
173 | tree type = outer_type; | |
174 | HOST_WIDE_INT cur_offset = offset; | |
175 | bool speculative = false; | |
176 | bool size_unknown = false; | |
b30df7b6 | 177 | unsigned HOST_WIDE_INT otr_type_size = POINTER_SIZE; |
aa803cc7 JH |
178 | |
179 | /* Update OUTER_TYPE to match EXPECTED_TYPE if it is not set. */ | |
180 | if (!outer_type) | |
181 | { | |
67a1b94c JH |
182 | clear_outer_type (otr_type); |
183 | type = otr_type; | |
aa803cc7 JH |
184 | cur_offset = 0; |
185 | } | |
186 | /* See if OFFSET points inside OUTER_TYPE. If it does not, we know | |
187 | that the context is either invalid, or the instance type must be | |
188 | derived from OUTER_TYPE. | |
189 | ||
190 | Because the instance type may contain field whose type is of OUTER_TYPE, | |
191 | we can not derive any effective information about it. | |
192 | ||
193 | TODO: In the case we know all derrived types, we can definitely do better | |
194 | here. */ | |
195 | else if (TYPE_SIZE (outer_type) | |
196 | && tree_fits_shwi_p (TYPE_SIZE (outer_type)) | |
197 | && tree_to_shwi (TYPE_SIZE (outer_type)) >= 0 | |
198 | && tree_to_shwi (TYPE_SIZE (outer_type)) <= offset) | |
199 | { | |
67a1b94c JH |
200 | clear_outer_type (otr_type); |
201 | type = otr_type; | |
aa803cc7 JH |
202 | cur_offset = 0; |
203 | ||
4081ada2 JH |
204 | /* If derived type is not allowed, we know that the context is invalid. |
205 | For dynamic types, we really do not have information about | |
206 | size of the memory location. It is possible that completely | |
207 | different type is stored after outer_type. */ | |
208 | if (!maybe_derived_type && !dynamic) | |
aa803cc7 JH |
209 | { |
210 | clear_speculation (); | |
211 | invalid = true; | |
212 | return false; | |
213 | } | |
214 | } | |
215 | ||
67a1b94c JH |
216 | if (otr_type && TYPE_SIZE (otr_type) |
217 | && tree_fits_shwi_p (TYPE_SIZE (otr_type))) | |
218 | otr_type_size = tree_to_uhwi (TYPE_SIZE (otr_type)); | |
aa803cc7 | 219 | |
67a1b94c | 220 | if (!type || offset < 0) |
aa803cc7 JH |
221 | goto no_useful_type_info; |
222 | ||
223 | /* Find the sub-object the constant actually refers to and mark whether it is | |
224 | an artificial one (as opposed to a user-defined one). | |
225 | ||
226 | This loop is performed twice; first time for outer_type and second time | |
227 | for speculative_outer_type. The second run has SPECULATIVE set. */ | |
228 | while (true) | |
229 | { | |
67a1b94c | 230 | unsigned HOST_WIDE_INT pos, size; |
aa803cc7 JH |
231 | tree fld; |
232 | ||
233 | /* If we do not know size of TYPE, we need to be more conservative | |
234 | about accepting cases where we can not find EXPECTED_TYPE. | |
235 | Generally the types that do matter here are of constant size. | |
236 | Size_unknown case should be very rare. */ | |
237 | if (TYPE_SIZE (type) | |
238 | && tree_fits_shwi_p (TYPE_SIZE (type)) | |
239 | && tree_to_shwi (TYPE_SIZE (type)) >= 0) | |
240 | size_unknown = false; | |
241 | else | |
242 | size_unknown = true; | |
243 | ||
244 | /* On a match, just return what we found. */ | |
67a1b94c JH |
245 | if ((otr_type |
246 | && types_odr_comparable (type, otr_type) | |
247 | && types_same_for_odr (type, otr_type)) | |
248 | || (!otr_type | |
aa803cc7 JH |
249 | && TREE_CODE (type) == RECORD_TYPE |
250 | && TYPE_BINFO (type) | |
251 | && polymorphic_type_binfo_p (TYPE_BINFO (type)))) | |
252 | { | |
253 | if (speculative) | |
254 | { | |
255 | /* If we did not match the offset, just give up on speculation. */ | |
256 | if (cur_offset != 0 | |
257 | /* Also check if speculation did not end up being same as | |
258 | non-speculation. */ | |
259 | || (types_must_be_same_for_odr (speculative_outer_type, | |
260 | outer_type) | |
261 | && (maybe_derived_type | |
262 | == speculative_maybe_derived_type))) | |
263 | clear_speculation (); | |
264 | return true; | |
265 | } | |
266 | else | |
267 | { | |
268 | /* If type is known to be final, do not worry about derived | |
269 | types. Testing it here may help us to avoid speculation. */ | |
67a1b94c JH |
270 | if (otr_type && TREE_CODE (outer_type) == RECORD_TYPE |
271 | && (!in_lto_p || odr_type_p (outer_type)) | |
4d6eb35a JH |
272 | && type_with_linkage_p (outer_type) |
273 | && type_known_to_have_no_derivations_p (outer_type)) | |
aa803cc7 JH |
274 | maybe_derived_type = false; |
275 | ||
276 | /* Type can not contain itself on an non-zero offset. In that case | |
277 | just give up. Still accept the case where size is now known. | |
278 | Either the second copy may appear past the end of type or within | |
279 | the non-POD buffer located inside the variably sized type | |
280 | itself. */ | |
281 | if (cur_offset != 0) | |
282 | goto no_useful_type_info; | |
283 | /* If we determined type precisely or we have no clue on | |
284 | speuclation, we are done. */ | |
67a1b94c JH |
285 | if (!maybe_derived_type || !speculative_outer_type |
286 | || !speculation_consistent_p (speculative_outer_type, | |
287 | speculative_offset, | |
288 | speculative_maybe_derived_type, | |
289 | otr_type)) | |
aa803cc7 JH |
290 | { |
291 | clear_speculation (); | |
292 | return true; | |
293 | } | |
294 | /* Otherwise look into speculation now. */ | |
295 | else | |
296 | { | |
297 | speculative = true; | |
298 | type = speculative_outer_type; | |
299 | cur_offset = speculative_offset; | |
300 | continue; | |
301 | } | |
302 | } | |
303 | } | |
304 | ||
305 | /* Walk fields and find corresponding on at OFFSET. */ | |
306 | if (TREE_CODE (type) == RECORD_TYPE) | |
307 | { | |
308 | for (fld = TYPE_FIELDS (type); fld; fld = DECL_CHAIN (fld)) | |
309 | { | |
310 | if (TREE_CODE (fld) != FIELD_DECL) | |
311 | continue; | |
312 | ||
313 | pos = int_bit_position (fld); | |
67a1b94c JH |
314 | if (pos > (unsigned HOST_WIDE_INT)cur_offset) |
315 | continue; | |
29c43c83 JH |
316 | |
317 | /* Do not consider vptr itself. Not even for placement new. */ | |
318 | if (!pos && DECL_ARTIFICIAL (fld) | |
319 | && POINTER_TYPE_P (TREE_TYPE (fld)) | |
320 | && TYPE_BINFO (type) | |
321 | && polymorphic_type_binfo_p (TYPE_BINFO (type))) | |
322 | continue; | |
323 | ||
67a1b94c JH |
324 | if (!DECL_SIZE (fld) || !tree_fits_uhwi_p (DECL_SIZE (fld))) |
325 | goto no_useful_type_info; | |
aa803cc7 | 326 | size = tree_to_uhwi (DECL_SIZE (fld)); |
67a1b94c JH |
327 | |
328 | /* We can always skip types smaller than pointer size: | |
329 | those can not contain a virtual table pointer. | |
330 | ||
331 | Disqualifying fields that are too small to fit OTR_TYPE | |
332 | saves work needed to walk them for no benefit. | |
333 | Because of the way the bases are packed into a class, the | |
334 | field's size may be smaller than type size, so it needs | |
335 | to be done with a care. */ | |
336 | ||
337 | if (pos <= (unsigned HOST_WIDE_INT)cur_offset | |
338 | && (pos + size) >= (unsigned HOST_WIDE_INT)cur_offset | |
b30df7b6 | 339 | + POINTER_SIZE |
67a1b94c JH |
340 | && (!otr_type |
341 | || !TYPE_SIZE (TREE_TYPE (fld)) | |
342 | || !tree_fits_shwi_p (TYPE_SIZE (TREE_TYPE (fld))) | |
343 | || (pos + tree_to_uhwi (TYPE_SIZE (TREE_TYPE (fld)))) | |
344 | >= cur_offset + otr_type_size)) | |
aa803cc7 JH |
345 | break; |
346 | } | |
347 | ||
348 | if (!fld) | |
349 | goto no_useful_type_info; | |
350 | ||
351 | type = TYPE_MAIN_VARIANT (TREE_TYPE (fld)); | |
352 | cur_offset -= pos; | |
353 | /* DECL_ARTIFICIAL represents a basetype. */ | |
354 | if (!DECL_ARTIFICIAL (fld)) | |
355 | { | |
356 | if (!speculative) | |
357 | { | |
358 | outer_type = type; | |
359 | offset = cur_offset; | |
360 | /* As soon as we se an field containing the type, | |
361 | we know we are not looking for derivations. */ | |
362 | maybe_derived_type = false; | |
363 | } | |
364 | else | |
365 | { | |
366 | speculative_outer_type = type; | |
367 | speculative_offset = cur_offset; | |
368 | speculative_maybe_derived_type = false; | |
369 | } | |
370 | } | |
67a1b94c JH |
371 | else if (!consider_bases) |
372 | goto no_useful_type_info; | |
aa803cc7 JH |
373 | } |
374 | else if (TREE_CODE (type) == ARRAY_TYPE) | |
375 | { | |
376 | tree subtype = TYPE_MAIN_VARIANT (TREE_TYPE (type)); | |
377 | ||
67a1b94c JH |
378 | /* Give up if we don't know array field size. |
379 | Also give up on non-polymorphic types as they are used | |
380 | as buffers for placement new. */ | |
aa803cc7 JH |
381 | if (!TYPE_SIZE (subtype) |
382 | || !tree_fits_shwi_p (TYPE_SIZE (subtype)) | |
383 | || tree_to_shwi (TYPE_SIZE (subtype)) <= 0 | |
384 | || !contains_polymorphic_type_p (subtype)) | |
385 | goto no_useful_type_info; | |
386 | ||
387 | HOST_WIDE_INT new_offset = cur_offset % tree_to_shwi (TYPE_SIZE (subtype)); | |
388 | ||
389 | /* We may see buffer for placement new. In this case the expected type | |
390 | can be bigger than the subtype. */ | |
391 | if (TYPE_SIZE (subtype) | |
67a1b94c | 392 | && (cur_offset + otr_type_size |
ec1d732b | 393 | > tree_to_uhwi (TYPE_SIZE (subtype)))) |
aa803cc7 JH |
394 | goto no_useful_type_info; |
395 | ||
396 | cur_offset = new_offset; | |
4d6eb35a | 397 | type = TYPE_MAIN_VARIANT (subtype); |
aa803cc7 JH |
398 | if (!speculative) |
399 | { | |
400 | outer_type = type; | |
401 | offset = cur_offset; | |
402 | maybe_derived_type = false; | |
403 | } | |
404 | else | |
405 | { | |
406 | speculative_outer_type = type; | |
407 | speculative_offset = cur_offset; | |
408 | speculative_maybe_derived_type = false; | |
409 | } | |
410 | } | |
411 | /* Give up on anything else. */ | |
412 | else | |
413 | { | |
414 | no_useful_type_info: | |
67a1b94c JH |
415 | if (maybe_derived_type && !speculative |
416 | && TREE_CODE (outer_type) == RECORD_TYPE | |
417 | && TREE_CODE (otr_type) == RECORD_TYPE | |
418 | && TYPE_BINFO (otr_type) | |
419 | && !offset | |
420 | && get_binfo_at_offset (TYPE_BINFO (otr_type), 0, outer_type)) | |
421 | { | |
422 | clear_outer_type (otr_type); | |
423 | if (!speculative_outer_type | |
424 | || !speculation_consistent_p (speculative_outer_type, | |
425 | speculative_offset, | |
426 | speculative_maybe_derived_type, | |
427 | otr_type)) | |
428 | clear_speculation (); | |
429 | if (speculative_outer_type) | |
430 | { | |
431 | speculative = true; | |
432 | type = speculative_outer_type; | |
433 | cur_offset = speculative_offset; | |
434 | } | |
435 | else | |
436 | return true; | |
437 | } | |
aa803cc7 JH |
438 | /* We found no way to embedd EXPECTED_TYPE in TYPE. |
439 | We still permit two special cases - placement new and | |
440 | the case of variadic types containing themselves. */ | |
441 | if (!speculative | |
67a1b94c JH |
442 | && consider_placement_new |
443 | && (size_unknown || !type || maybe_derived_type | |
444 | || possible_placement_new (type, otr_type, cur_offset))) | |
aa803cc7 JH |
445 | { |
446 | /* In these weird cases we want to accept the context. | |
447 | In non-speculative run we have no useful outer_type info | |
448 | (TODO: we may eventually want to record upper bound on the | |
449 | type size that can be used to prune the walk), | |
450 | but we still want to consider speculation that may | |
451 | give useful info. */ | |
452 | if (!speculative) | |
453 | { | |
67a1b94c JH |
454 | clear_outer_type (otr_type); |
455 | if (!speculative_outer_type | |
456 | || !speculation_consistent_p (speculative_outer_type, | |
457 | speculative_offset, | |
458 | speculative_maybe_derived_type, | |
459 | otr_type)) | |
460 | clear_speculation (); | |
aa803cc7 JH |
461 | if (speculative_outer_type) |
462 | { | |
463 | speculative = true; | |
464 | type = speculative_outer_type; | |
465 | cur_offset = speculative_offset; | |
466 | } | |
467 | else | |
468 | return true; | |
469 | } | |
470 | else | |
471 | clear_speculation (); | |
472 | return true; | |
473 | } | |
474 | else | |
475 | { | |
476 | clear_speculation (); | |
477 | if (speculative) | |
478 | return true; | |
67a1b94c | 479 | clear_outer_type (otr_type); |
aa803cc7 JH |
480 | invalid = true; |
481 | return false; | |
482 | } | |
483 | } | |
484 | } | |
485 | } | |
486 | ||
67a1b94c JH |
487 | /* Return true if OUTER_TYPE contains OTR_TYPE at OFFSET. |
488 | CONSIDER_PLACEMENT_NEW makes function to accept cases where OTR_TYPE can | |
489 | be built within OUTER_TYPE by means of placement new. CONSIDER_BASES makes | |
490 | function to accept cases where OTR_TYPE appears as base of OUTER_TYPE or as | |
491 | base of one of fields of OUTER_TYPE. */ | |
aa803cc7 JH |
492 | |
493 | static bool | |
494 | contains_type_p (tree outer_type, HOST_WIDE_INT offset, | |
67a1b94c JH |
495 | tree otr_type, |
496 | bool consider_placement_new, | |
497 | bool consider_bases) | |
aa803cc7 JH |
498 | { |
499 | ipa_polymorphic_call_context context; | |
67a1b94c JH |
500 | |
501 | /* Check that type is within range. */ | |
502 | if (offset < 0) | |
503 | return false; | |
504 | if (TYPE_SIZE (outer_type) && TYPE_SIZE (otr_type) | |
505 | && TREE_CODE (outer_type) == INTEGER_CST | |
506 | && TREE_CODE (otr_type) == INTEGER_CST | |
507 | && wi::ltu_p (wi::to_offset (outer_type), (wi::to_offset (otr_type) + offset))) | |
508 | return false; | |
509 | ||
aa803cc7 JH |
510 | context.offset = offset; |
511 | context.outer_type = TYPE_MAIN_VARIANT (outer_type); | |
512 | context.maybe_derived_type = false; | |
67a1b94c | 513 | return context.restrict_to_inner_class (otr_type, consider_placement_new, consider_bases); |
aa803cc7 JH |
514 | } |
515 | ||
516 | ||
00a0ea64 JJ |
517 | /* Return a FUNCTION_DECL if BLOCK represents a constructor or destructor. |
518 | If CHECK_CLONES is true, also check for clones of ctor/dtors. */ | |
519 | ||
520 | tree | |
521 | inlined_polymorphic_ctor_dtor_block_p (tree block, bool check_clones) | |
522 | { | |
523 | tree fn = BLOCK_ABSTRACT_ORIGIN (block); | |
524 | if (fn == NULL || TREE_CODE (fn) != FUNCTION_DECL) | |
525 | return NULL_TREE; | |
526 | ||
527 | if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE | |
528 | || (!DECL_CXX_CONSTRUCTOR_P (fn) && !DECL_CXX_DESTRUCTOR_P (fn))) | |
529 | { | |
530 | if (!check_clones) | |
531 | return NULL_TREE; | |
532 | ||
533 | /* Watch for clones where we constant propagated the first | |
534 | argument (pointer to the instance). */ | |
535 | fn = DECL_ABSTRACT_ORIGIN (fn); | |
536 | if (!fn | |
537 | || TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE | |
538 | || (!DECL_CXX_CONSTRUCTOR_P (fn) && !DECL_CXX_DESTRUCTOR_P (fn))) | |
539 | return NULL_TREE; | |
540 | } | |
541 | ||
542 | if (flags_from_decl_or_type (fn) & (ECF_PURE | ECF_CONST)) | |
543 | return NULL_TREE; | |
544 | ||
545 | return fn; | |
546 | } | |
547 | ||
548 | ||
aa803cc7 JH |
549 | /* We know that the instance is stored in variable or parameter |
550 | (not dynamically allocated) and we want to disprove the fact | |
551 | that it may be in construction at invocation of CALL. | |
552 | ||
91e50b2d JH |
553 | BASE represents memory location where instance is stored. |
554 | If BASE is NULL, it is assumed to be global memory. | |
555 | OUTER_TYPE is known type of the instance or NULL if not | |
556 | known. | |
557 | ||
aa803cc7 JH |
558 | For the variable to be in construction we actually need to |
559 | be in constructor of corresponding global variable or | |
560 | the inline stack of CALL must contain the constructor. | |
561 | Check this condition. This check works safely only before | |
562 | IPA passes, because inline stacks may become out of date | |
563 | later. */ | |
564 | ||
565 | bool | |
566 | decl_maybe_in_construction_p (tree base, tree outer_type, | |
567 | gimple call, tree function) | |
568 | { | |
91e50b2d JH |
569 | if (outer_type) |
570 | outer_type = TYPE_MAIN_VARIANT (outer_type); | |
571 | gcc_assert (!base || DECL_P (base)); | |
aa803cc7 JH |
572 | |
573 | /* After inlining the code unification optimizations may invalidate | |
574 | inline stacks. Also we need to give up on global variables after | |
575 | IPA, because addresses of these may have been propagated to their | |
576 | constructors. */ | |
577 | if (DECL_STRUCT_FUNCTION (function)->after_inlining) | |
578 | return true; | |
579 | ||
580 | /* Pure functions can not do any changes on the dynamic type; | |
581 | that require writting to memory. */ | |
91e50b2d | 582 | if ((!base || !auto_var_in_fn_p (base, function)) |
aa803cc7 JH |
583 | && flags_from_decl_or_type (function) & (ECF_PURE | ECF_CONST)) |
584 | return false; | |
585 | ||
00a0ea64 | 586 | bool check_clones = !base || is_global_var (base); |
aa803cc7 JH |
587 | for (tree block = gimple_block (call); block && TREE_CODE (block) == BLOCK; |
588 | block = BLOCK_SUPERCONTEXT (block)) | |
00a0ea64 | 589 | if (tree fn = inlined_polymorphic_ctor_dtor_block_p (block, check_clones)) |
aa803cc7 | 590 | { |
70e7f2a2 | 591 | tree type = TYPE_METHOD_BASETYPE (TREE_TYPE (fn)); |
91e50b2d JH |
592 | |
593 | if (!outer_type || !types_odr_comparable (type, outer_type)) | |
594 | { | |
595 | if (TREE_CODE (type) == RECORD_TYPE | |
596 | && TYPE_BINFO (type) | |
597 | && polymorphic_type_binfo_p (TYPE_BINFO (type))) | |
598 | return true; | |
599 | } | |
600 | else if (types_same_for_odr (type, outer_type)) | |
aa803cc7 JH |
601 | return true; |
602 | } | |
603 | ||
91e50b2d | 604 | if (!base || (TREE_CODE (base) == VAR_DECL && is_global_var (base))) |
aa803cc7 JH |
605 | { |
606 | if (TREE_CODE (TREE_TYPE (function)) != METHOD_TYPE | |
607 | || (!DECL_CXX_CONSTRUCTOR_P (function) | |
608 | && !DECL_CXX_DESTRUCTOR_P (function))) | |
609 | { | |
610 | if (!DECL_ABSTRACT_ORIGIN (function)) | |
611 | return false; | |
612 | /* Watch for clones where we constant propagated the first | |
613 | argument (pointer to the instance). */ | |
614 | function = DECL_ABSTRACT_ORIGIN (function); | |
615 | if (!function | |
616 | || TREE_CODE (TREE_TYPE (function)) != METHOD_TYPE | |
617 | || (!DECL_CXX_CONSTRUCTOR_P (function) | |
618 | && !DECL_CXX_DESTRUCTOR_P (function))) | |
619 | return false; | |
620 | } | |
70e7f2a2 | 621 | tree type = TYPE_METHOD_BASETYPE (TREE_TYPE (function)); |
91e50b2d JH |
622 | if (!outer_type || !types_odr_comparable (type, outer_type)) |
623 | { | |
624 | if (TREE_CODE (type) == RECORD_TYPE | |
625 | && TYPE_BINFO (type) | |
626 | && polymorphic_type_binfo_p (TYPE_BINFO (type))) | |
627 | return true; | |
628 | } | |
629 | else if (types_same_for_odr (type, outer_type)) | |
aa803cc7 JH |
630 | return true; |
631 | } | |
632 | return false; | |
633 | } | |
634 | ||
44210a96 MJ |
635 | /* Dump human readable context to F. If NEWLINE is true, it will be terminated |
636 | by a newline. */ | |
aa803cc7 JH |
637 | |
638 | void | |
44210a96 | 639 | ipa_polymorphic_call_context::dump (FILE *f, bool newline) const |
aa803cc7 JH |
640 | { |
641 | fprintf (f, " "); | |
642 | if (invalid) | |
29c43c83 | 643 | fprintf (f, "Call is known to be undefined"); |
aa803cc7 JH |
644 | else |
645 | { | |
67a1b94c JH |
646 | if (useless_p ()) |
647 | fprintf (f, "nothing known"); | |
aa803cc7 JH |
648 | if (outer_type || offset) |
649 | { | |
4081ada2 | 650 | fprintf (f, "Outer type%s:", dynamic ? " (dynamic)":""); |
aa803cc7 JH |
651 | print_generic_expr (f, outer_type, TDF_SLIM); |
652 | if (maybe_derived_type) | |
653 | fprintf (f, " (or a derived type)"); | |
654 | if (maybe_in_construction) | |
655 | fprintf (f, " (maybe in construction)"); | |
16998094 | 656 | fprintf (f, " offset " HOST_WIDE_INT_PRINT_DEC, |
aa803cc7 JH |
657 | offset); |
658 | } | |
659 | if (speculative_outer_type) | |
660 | { | |
67a1b94c JH |
661 | if (outer_type || offset) |
662 | fprintf (f, " "); | |
663 | fprintf (f, "Speculative outer type:"); | |
aa803cc7 JH |
664 | print_generic_expr (f, speculative_outer_type, TDF_SLIM); |
665 | if (speculative_maybe_derived_type) | |
666 | fprintf (f, " (or a derived type)"); | |
16998094 | 667 | fprintf (f, " at offset " HOST_WIDE_INT_PRINT_DEC, |
aa803cc7 JH |
668 | speculative_offset); |
669 | } | |
670 | } | |
44210a96 MJ |
671 | if (newline) |
672 | fprintf(f, "\n"); | |
aa803cc7 JH |
673 | } |
674 | ||
675 | /* Print context to stderr. */ | |
676 | ||
677 | void | |
678 | ipa_polymorphic_call_context::debug () const | |
679 | { | |
680 | dump (stderr); | |
681 | } | |
682 | ||
683 | /* Stream out the context to OB. */ | |
684 | ||
685 | void | |
686 | ipa_polymorphic_call_context::stream_out (struct output_block *ob) const | |
687 | { | |
688 | struct bitpack_d bp = bitpack_create (ob->main_stream); | |
689 | ||
690 | bp_pack_value (&bp, invalid, 1); | |
691 | bp_pack_value (&bp, maybe_in_construction, 1); | |
692 | bp_pack_value (&bp, maybe_derived_type, 1); | |
693 | bp_pack_value (&bp, speculative_maybe_derived_type, 1); | |
4081ada2 | 694 | bp_pack_value (&bp, dynamic, 1); |
aa803cc7 JH |
695 | bp_pack_value (&bp, outer_type != NULL, 1); |
696 | bp_pack_value (&bp, offset != 0, 1); | |
697 | bp_pack_value (&bp, speculative_outer_type != NULL, 1); | |
698 | streamer_write_bitpack (&bp); | |
699 | ||
700 | if (outer_type != NULL) | |
701 | stream_write_tree (ob, outer_type, true); | |
702 | if (offset) | |
703 | streamer_write_hwi (ob, offset); | |
704 | if (speculative_outer_type != NULL) | |
705 | { | |
706 | stream_write_tree (ob, speculative_outer_type, true); | |
707 | streamer_write_hwi (ob, speculative_offset); | |
708 | } | |
709 | else | |
710 | gcc_assert (!speculative_offset); | |
711 | } | |
712 | ||
713 | /* Stream in the context from IB and DATA_IN. */ | |
714 | ||
715 | void | |
716 | ipa_polymorphic_call_context::stream_in (struct lto_input_block *ib, | |
717 | struct data_in *data_in) | |
718 | { | |
719 | struct bitpack_d bp = streamer_read_bitpack (ib); | |
720 | ||
721 | invalid = bp_unpack_value (&bp, 1); | |
722 | maybe_in_construction = bp_unpack_value (&bp, 1); | |
723 | maybe_derived_type = bp_unpack_value (&bp, 1); | |
724 | speculative_maybe_derived_type = bp_unpack_value (&bp, 1); | |
4081ada2 | 725 | dynamic = bp_unpack_value (&bp, 1); |
aa803cc7 JH |
726 | bool outer_type_p = bp_unpack_value (&bp, 1); |
727 | bool offset_p = bp_unpack_value (&bp, 1); | |
728 | bool speculative_outer_type_p = bp_unpack_value (&bp, 1); | |
729 | ||
730 | if (outer_type_p) | |
731 | outer_type = stream_read_tree (ib, data_in); | |
732 | else | |
733 | outer_type = NULL; | |
734 | if (offset_p) | |
735 | offset = (HOST_WIDE_INT) streamer_read_hwi (ib); | |
736 | else | |
737 | offset = 0; | |
738 | if (speculative_outer_type_p) | |
739 | { | |
740 | speculative_outer_type = stream_read_tree (ib, data_in); | |
741 | speculative_offset = (HOST_WIDE_INT) streamer_read_hwi (ib); | |
742 | } | |
743 | else | |
744 | { | |
745 | speculative_outer_type = NULL; | |
746 | speculative_offset = 0; | |
747 | } | |
748 | } | |
749 | ||
750 | /* Proudce polymorphic call context for call method of instance | |
751 | that is located within BASE (that is assumed to be a decl) at offset OFF. */ | |
752 | ||
753 | void | |
754 | ipa_polymorphic_call_context::set_by_decl (tree base, HOST_WIDE_INT off) | |
755 | { | |
756 | gcc_assert (DECL_P (base)); | |
4081ada2 | 757 | clear_speculation (); |
aa803cc7 | 758 | |
4081ada2 JH |
759 | if (!contains_polymorphic_type_p (TREE_TYPE (base))) |
760 | { | |
761 | clear_outer_type (); | |
762 | offset = off; | |
763 | return; | |
764 | } | |
aa803cc7 JH |
765 | outer_type = TYPE_MAIN_VARIANT (TREE_TYPE (base)); |
766 | offset = off; | |
aa803cc7 JH |
767 | /* Make very conservative assumption that all objects |
768 | may be in construction. | |
769 | ||
770 | It is up to caller to revisit this via | |
771 | get_dynamic_type or decl_maybe_in_construction_p. */ | |
772 | maybe_in_construction = true; | |
773 | maybe_derived_type = false; | |
4081ada2 | 774 | dynamic = false; |
aa803cc7 JH |
775 | } |
776 | ||
777 | /* CST is an invariant (address of decl), try to get meaningful | |
778 | polymorphic call context for polymorphic call of method | |
779 | if instance of OTR_TYPE that is located at offset OFF of this invariant. | |
780 | Return FALSE if nothing meaningful can be found. */ | |
781 | ||
782 | bool | |
783 | ipa_polymorphic_call_context::set_by_invariant (tree cst, | |
784 | tree otr_type, | |
785 | HOST_WIDE_INT off) | |
786 | { | |
787 | HOST_WIDE_INT offset2, size, max_size; | |
788 | tree base; | |
789 | ||
790 | invalid = false; | |
791 | off = 0; | |
792 | clear_outer_type (otr_type); | |
793 | ||
794 | if (TREE_CODE (cst) != ADDR_EXPR) | |
795 | return false; | |
796 | ||
797 | cst = TREE_OPERAND (cst, 0); | |
798 | base = get_ref_base_and_extent (cst, &offset2, &size, &max_size); | |
799 | if (!DECL_P (base) || max_size == -1 || max_size != size) | |
800 | return false; | |
801 | ||
802 | /* Only type inconsistent programs can have otr_type that is | |
803 | not part of outer type. */ | |
804 | if (otr_type && !contains_type_p (TREE_TYPE (base), off, otr_type)) | |
805 | return false; | |
806 | ||
807 | set_by_decl (base, off); | |
808 | return true; | |
809 | } | |
810 | ||
811 | /* See if OP is SSA name initialized as a copy or by single assignment. | |
29c43c83 JH |
812 | If so, walk the SSA graph up. Because simple PHI conditional is considered |
813 | copy, GLOBAL_VISITED may be used to avoid infinite loop walking the SSA | |
814 | graph. */ | |
aa803cc7 JH |
815 | |
816 | static tree | |
29c43c83 | 817 | walk_ssa_copies (tree op, hash_set<tree> **global_visited = NULL) |
aa803cc7 | 818 | { |
29c43c83 | 819 | hash_set <tree> *visited = NULL; |
aa803cc7 JH |
820 | STRIP_NOPS (op); |
821 | while (TREE_CODE (op) == SSA_NAME | |
822 | && !SSA_NAME_IS_DEFAULT_DEF (op) | |
b3406fa0 RB |
823 | /* We might be called via fold_stmt during cfgcleanup where |
824 | SSA form need not be up-to-date. */ | |
825 | && !name_registered_for_update_p (op) | |
0127c169 JH |
826 | && (gimple_assign_single_p (SSA_NAME_DEF_STMT (op)) |
827 | || gimple_code (SSA_NAME_DEF_STMT (op)) == GIMPLE_PHI)) | |
aa803cc7 | 828 | { |
29c43c83 JH |
829 | if (global_visited) |
830 | { | |
831 | if (!*global_visited) | |
832 | *global_visited = new hash_set<tree>; | |
833 | if ((*global_visited)->add (op)) | |
834 | goto done; | |
835 | } | |
836 | else | |
837 | { | |
838 | if (!visited) | |
839 | visited = new hash_set<tree>; | |
840 | if (visited->add (op)) | |
841 | goto done; | |
842 | } | |
0127c169 JH |
843 | /* Special case |
844 | if (ptr == 0) | |
845 | ptr = 0; | |
846 | else | |
847 | ptr = ptr.foo; | |
848 | This pattern is implicitly produced for casts to non-primary | |
849 | bases. When doing context analysis, we do not really care | |
850 | about the case pointer is NULL, becuase the call will be | |
851 | undefined anyway. */ | |
852 | if (gimple_code (SSA_NAME_DEF_STMT (op)) == GIMPLE_PHI) | |
853 | { | |
854 | gimple phi = SSA_NAME_DEF_STMT (op); | |
855 | ||
b3406fa0 | 856 | if (gimple_phi_num_args (phi) > 2) |
29c43c83 JH |
857 | goto done; |
858 | if (gimple_phi_num_args (phi) == 1) | |
859 | op = gimple_phi_arg_def (phi, 0); | |
860 | else if (integer_zerop (gimple_phi_arg_def (phi, 0))) | |
0127c169 JH |
861 | op = gimple_phi_arg_def (phi, 1); |
862 | else if (integer_zerop (gimple_phi_arg_def (phi, 1))) | |
863 | op = gimple_phi_arg_def (phi, 0); | |
864 | else | |
29c43c83 | 865 | goto done; |
0127c169 JH |
866 | } |
867 | else | |
868 | { | |
869 | if (gimple_assign_load_p (SSA_NAME_DEF_STMT (op))) | |
29c43c83 | 870 | goto done; |
0127c169 JH |
871 | op = gimple_assign_rhs1 (SSA_NAME_DEF_STMT (op)); |
872 | } | |
aa803cc7 JH |
873 | STRIP_NOPS (op); |
874 | } | |
29c43c83 JH |
875 | done: |
876 | if (visited) | |
877 | delete (visited); | |
aa803cc7 JH |
878 | return op; |
879 | } | |
880 | ||
881 | /* Create polymorphic call context from IP invariant CST. | |
882 | This is typically &global_var. | |
883 | OTR_TYPE specify type of polymorphic call or NULL if unknown, OFF | |
884 | is offset of call. */ | |
885 | ||
886 | ipa_polymorphic_call_context::ipa_polymorphic_call_context (tree cst, | |
887 | tree otr_type, | |
888 | HOST_WIDE_INT off) | |
889 | { | |
890 | clear_speculation (); | |
891 | set_by_invariant (cst, otr_type, off); | |
892 | } | |
893 | ||
894 | /* Build context for pointer REF contained in FNDECL at statement STMT. | |
895 | if INSTANCE is non-NULL, return pointer to the object described by | |
896 | the context or DECL where context is contained in. */ | |
897 | ||
898 | ipa_polymorphic_call_context::ipa_polymorphic_call_context (tree fndecl, | |
899 | tree ref, | |
900 | gimple stmt, | |
901 | tree *instance) | |
902 | { | |
903 | tree otr_type = NULL; | |
904 | tree base_pointer; | |
29c43c83 | 905 | hash_set <tree> *visited = NULL; |
aa803cc7 JH |
906 | |
907 | if (TREE_CODE (ref) == OBJ_TYPE_REF) | |
908 | { | |
909 | otr_type = obj_type_ref_class (ref); | |
910 | base_pointer = OBJ_TYPE_REF_OBJECT (ref); | |
911 | } | |
912 | else | |
913 | base_pointer = ref; | |
914 | ||
915 | /* Set up basic info in case we find nothing interesting in the analysis. */ | |
916 | clear_speculation (); | |
917 | clear_outer_type (otr_type); | |
918 | invalid = false; | |
919 | ||
920 | /* Walk SSA for outer object. */ | |
29c43c83 | 921 | while (true) |
aa803cc7 | 922 | { |
29c43c83 | 923 | base_pointer = walk_ssa_copies (base_pointer, &visited); |
aa803cc7 JH |
924 | if (TREE_CODE (base_pointer) == ADDR_EXPR) |
925 | { | |
926 | HOST_WIDE_INT size, max_size; | |
927 | HOST_WIDE_INT offset2; | |
928 | tree base = get_ref_base_and_extent (TREE_OPERAND (base_pointer, 0), | |
929 | &offset2, &size, &max_size); | |
930 | ||
67a1b94c | 931 | if (max_size != -1 && max_size == size) |
07f4a83d | 932 | combine_speculation_with (TYPE_MAIN_VARIANT (TREE_TYPE (base)), |
67a1b94c JH |
933 | offset + offset2, |
934 | true, | |
935 | NULL /* Do not change outer type. */); | |
936 | ||
aa803cc7 JH |
937 | /* If this is a varying address, punt. */ |
938 | if ((TREE_CODE (base) == MEM_REF || DECL_P (base)) | |
939 | && max_size != -1 | |
940 | && max_size == size) | |
941 | { | |
942 | /* We found dereference of a pointer. Type of the pointer | |
943 | and MEM_REF is meaningless, but we can look futher. */ | |
944 | if (TREE_CODE (base) == MEM_REF) | |
945 | { | |
946 | base_pointer = TREE_OPERAND (base, 0); | |
947 | offset | |
948 | += offset2 + mem_ref_offset (base).to_short_addr () * BITS_PER_UNIT; | |
949 | outer_type = NULL; | |
950 | } | |
951 | /* We found base object. In this case the outer_type | |
952 | is known. */ | |
953 | else if (DECL_P (base)) | |
954 | { | |
29c43c83 JH |
955 | if (visited) |
956 | delete (visited); | |
aa803cc7 JH |
957 | /* Only type inconsistent programs can have otr_type that is |
958 | not part of outer type. */ | |
959 | if (otr_type | |
960 | && !contains_type_p (TREE_TYPE (base), | |
961 | offset + offset2, otr_type)) | |
962 | { | |
963 | invalid = true; | |
964 | if (instance) | |
965 | *instance = base_pointer; | |
966 | return; | |
967 | } | |
968 | set_by_decl (base, offset + offset2); | |
4081ada2 | 969 | if (outer_type && maybe_in_construction && stmt) |
aa803cc7 JH |
970 | maybe_in_construction |
971 | = decl_maybe_in_construction_p (base, | |
972 | outer_type, | |
973 | stmt, | |
974 | fndecl); | |
975 | if (instance) | |
976 | *instance = base; | |
977 | return; | |
978 | } | |
979 | else | |
980 | break; | |
981 | } | |
982 | else | |
983 | break; | |
984 | } | |
985 | else if (TREE_CODE (base_pointer) == POINTER_PLUS_EXPR | |
986 | && tree_fits_uhwi_p (TREE_OPERAND (base_pointer, 1))) | |
987 | { | |
988 | offset += tree_to_shwi (TREE_OPERAND (base_pointer, 1)) | |
989 | * BITS_PER_UNIT; | |
990 | base_pointer = TREE_OPERAND (base_pointer, 0); | |
991 | } | |
992 | else | |
993 | break; | |
994 | } | |
29c43c83 JH |
995 | |
996 | if (visited) | |
997 | delete (visited); | |
aa803cc7 JH |
998 | |
999 | /* Try to determine type of the outer object. */ | |
1000 | if (TREE_CODE (base_pointer) == SSA_NAME | |
1001 | && SSA_NAME_IS_DEFAULT_DEF (base_pointer) | |
1002 | && TREE_CODE (SSA_NAME_VAR (base_pointer)) == PARM_DECL) | |
1003 | { | |
1004 | /* See if parameter is THIS pointer of a method. */ | |
1005 | if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE | |
1006 | && SSA_NAME_VAR (base_pointer) == DECL_ARGUMENTS (fndecl)) | |
1007 | { | |
1008 | outer_type | |
1009 | = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (base_pointer))); | |
67a1b94c JH |
1010 | gcc_assert (TREE_CODE (outer_type) == RECORD_TYPE |
1011 | || TREE_CODE (outer_type) == UNION_TYPE); | |
aa803cc7 JH |
1012 | |
1013 | /* Dynamic casting has possibly upcasted the type | |
1014 | in the hiearchy. In this case outer type is less | |
1015 | informative than inner type and we should forget | |
1016 | about it. */ | |
67a1b94c JH |
1017 | if ((otr_type |
1018 | && !contains_type_p (outer_type, offset, | |
1019 | otr_type)) | |
1020 | || !contains_polymorphic_type_p (outer_type)) | |
aa803cc7 JH |
1021 | { |
1022 | outer_type = NULL; | |
1023 | if (instance) | |
1024 | *instance = base_pointer; | |
1025 | return; | |
1026 | } | |
1027 | ||
4081ada2 JH |
1028 | dynamic = true; |
1029 | ||
aa803cc7 JH |
1030 | /* If the function is constructor or destructor, then |
1031 | the type is possibly in construction, but we know | |
1032 | it is not derived type. */ | |
1033 | if (DECL_CXX_CONSTRUCTOR_P (fndecl) | |
1034 | || DECL_CXX_DESTRUCTOR_P (fndecl)) | |
1035 | { | |
1036 | maybe_in_construction = true; | |
1037 | maybe_derived_type = false; | |
1038 | } | |
1039 | else | |
1040 | { | |
1041 | maybe_derived_type = true; | |
1042 | maybe_in_construction = false; | |
1043 | } | |
1044 | if (instance) | |
1045 | *instance = base_pointer; | |
1046 | return; | |
1047 | } | |
1048 | /* Non-PODs passed by value are really passed by invisible | |
1049 | reference. In this case we also know the type of the | |
1050 | object. */ | |
1051 | if (DECL_BY_REFERENCE (SSA_NAME_VAR (base_pointer))) | |
1052 | { | |
1053 | outer_type | |
1054 | = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (base_pointer))); | |
aa803cc7 JH |
1055 | /* Only type inconsistent programs can have otr_type that is |
1056 | not part of outer type. */ | |
67a1b94c JH |
1057 | if (otr_type && !contains_type_p (outer_type, offset, |
1058 | otr_type)) | |
aa803cc7 JH |
1059 | { |
1060 | invalid = true; | |
1061 | if (instance) | |
1062 | *instance = base_pointer; | |
1063 | return; | |
1064 | } | |
67a1b94c JH |
1065 | /* Non-polymorphic types have no interest for us. */ |
1066 | else if (!otr_type && !contains_polymorphic_type_p (outer_type)) | |
1067 | { | |
1068 | outer_type = NULL; | |
1069 | if (instance) | |
1070 | *instance = base_pointer; | |
1071 | return; | |
1072 | } | |
aa803cc7 JH |
1073 | maybe_derived_type = false; |
1074 | maybe_in_construction = false; | |
1075 | if (instance) | |
1076 | *instance = base_pointer; | |
1077 | return; | |
1078 | } | |
1079 | } | |
1080 | ||
1081 | tree base_type = TREE_TYPE (base_pointer); | |
1082 | ||
1083 | if (TREE_CODE (base_pointer) == SSA_NAME | |
1084 | && SSA_NAME_IS_DEFAULT_DEF (base_pointer) | |
b09e592e BE |
1085 | && !(TREE_CODE (SSA_NAME_VAR (base_pointer)) == PARM_DECL |
1086 | || TREE_CODE (SSA_NAME_VAR (base_pointer)) == RESULT_DECL)) | |
aa803cc7 JH |
1087 | { |
1088 | invalid = true; | |
1089 | if (instance) | |
1090 | *instance = base_pointer; | |
1091 | return; | |
1092 | } | |
1093 | if (TREE_CODE (base_pointer) == SSA_NAME | |
1094 | && SSA_NAME_DEF_STMT (base_pointer) | |
1095 | && gimple_assign_single_p (SSA_NAME_DEF_STMT (base_pointer))) | |
1096 | base_type = TREE_TYPE (gimple_assign_rhs1 | |
1097 | (SSA_NAME_DEF_STMT (base_pointer))); | |
1098 | ||
62c7e4b7 | 1099 | if (base_type && POINTER_TYPE_P (base_type)) |
67a1b94c JH |
1100 | combine_speculation_with (TYPE_MAIN_VARIANT (TREE_TYPE (base_type)), |
1101 | offset, | |
1102 | true, NULL /* Do not change type here */); | |
aa803cc7 JH |
1103 | /* TODO: There are multiple ways to derive a type. For instance |
1104 | if BASE_POINTER is passed to an constructor call prior our refernece. | |
1105 | We do not make this type of flow sensitive analysis yet. */ | |
1106 | if (instance) | |
1107 | *instance = base_pointer; | |
1108 | return; | |
1109 | } | |
1110 | ||
1111 | /* Structure to be passed in between detect_type_change and | |
1112 | check_stmt_for_type_change. */ | |
1113 | ||
1114 | struct type_change_info | |
1115 | { | |
1116 | /* Offset into the object where there is the virtual method pointer we are | |
1117 | looking for. */ | |
1118 | HOST_WIDE_INT offset; | |
1119 | /* The declaration or SSA_NAME pointer of the base that we are checking for | |
1120 | type change. */ | |
1121 | tree instance; | |
1122 | /* The reference to virtual table pointer used. */ | |
1123 | tree vtbl_ptr_ref; | |
1124 | tree otr_type; | |
1125 | /* If we actually can tell the type that the object has changed to, it is | |
1126 | stored in this field. Otherwise it remains NULL_TREE. */ | |
1127 | tree known_current_type; | |
1128 | HOST_WIDE_INT known_current_offset; | |
1129 | ||
1130 | /* Set to true if dynamic type change has been detected. */ | |
1131 | bool type_maybe_changed; | |
1132 | /* Set to true if multiple types have been encountered. known_current_type | |
1133 | must be disregarded in that case. */ | |
1134 | bool multiple_types_encountered; | |
1135 | /* Set to true if we possibly missed some dynamic type changes and we should | |
1136 | consider the set to be speculative. */ | |
1137 | bool speculative; | |
1138 | bool seen_unanalyzed_store; | |
1139 | }; | |
1140 | ||
1141 | /* Return true if STMT is not call and can modify a virtual method table pointer. | |
1142 | We take advantage of fact that vtable stores must appear within constructor | |
1143 | and destructor functions. */ | |
1144 | ||
1145 | static bool | |
1146 | noncall_stmt_may_be_vtbl_ptr_store (gimple stmt) | |
1147 | { | |
1148 | if (is_gimple_assign (stmt)) | |
1149 | { | |
1150 | tree lhs = gimple_assign_lhs (stmt); | |
1151 | ||
1152 | if (gimple_clobber_p (stmt)) | |
1153 | return false; | |
1154 | if (!AGGREGATE_TYPE_P (TREE_TYPE (lhs))) | |
1155 | { | |
1156 | if (flag_strict_aliasing | |
1157 | && !POINTER_TYPE_P (TREE_TYPE (lhs))) | |
1158 | return false; | |
1159 | ||
1160 | if (TREE_CODE (lhs) == COMPONENT_REF | |
1161 | && !DECL_VIRTUAL_P (TREE_OPERAND (lhs, 1))) | |
1162 | return false; | |
1163 | /* In the future we might want to use get_base_ref_and_offset to find | |
1164 | if there is a field corresponding to the offset and if so, proceed | |
1165 | almost like if it was a component ref. */ | |
1166 | } | |
1167 | } | |
1168 | ||
1169 | /* Code unification may mess with inline stacks. */ | |
1170 | if (cfun->after_inlining) | |
1171 | return true; | |
1172 | ||
1173 | /* Walk the inline stack and watch out for ctors/dtors. | |
1174 | TODO: Maybe we can require the store to appear in toplevel | |
1175 | block of CTOR/DTOR. */ | |
1176 | for (tree block = gimple_block (stmt); block && TREE_CODE (block) == BLOCK; | |
1177 | block = BLOCK_SUPERCONTEXT (block)) | |
1178 | if (BLOCK_ABSTRACT_ORIGIN (block) | |
1179 | && TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block)) == FUNCTION_DECL) | |
00a0ea64 | 1180 | return inlined_polymorphic_ctor_dtor_block_p (block, false); |
aa803cc7 JH |
1181 | return (TREE_CODE (TREE_TYPE (current_function_decl)) == METHOD_TYPE |
1182 | && (DECL_CXX_CONSTRUCTOR_P (current_function_decl) | |
1183 | || DECL_CXX_DESTRUCTOR_P (current_function_decl))); | |
1184 | } | |
1185 | ||
1186 | /* If STMT can be proved to be an assignment to the virtual method table | |
1187 | pointer of ANALYZED_OBJ and the type associated with the new table | |
1184bb78 JH |
1188 | identified, return the type. Otherwise return NULL_TREE if type changes |
1189 | in unknown way or ERROR_MARK_NODE if type is unchanged. */ | |
aa803cc7 JH |
1190 | |
1191 | static tree | |
1192 | extr_type_from_vtbl_ptr_store (gimple stmt, struct type_change_info *tci, | |
1193 | HOST_WIDE_INT *type_offset) | |
1194 | { | |
1195 | HOST_WIDE_INT offset, size, max_size; | |
1196 | tree lhs, rhs, base; | |
1197 | ||
1198 | if (!gimple_assign_single_p (stmt)) | |
1199 | return NULL_TREE; | |
1200 | ||
1201 | lhs = gimple_assign_lhs (stmt); | |
1202 | rhs = gimple_assign_rhs1 (stmt); | |
1203 | if (TREE_CODE (lhs) != COMPONENT_REF | |
1204 | || !DECL_VIRTUAL_P (TREE_OPERAND (lhs, 1))) | |
1205 | { | |
1206 | if (dump_file) | |
1207 | fprintf (dump_file, " LHS is not virtual table.\n"); | |
1208 | return NULL_TREE; | |
1209 | } | |
1210 | ||
1211 | if (tci->vtbl_ptr_ref && operand_equal_p (lhs, tci->vtbl_ptr_ref, 0)) | |
1212 | ; | |
1213 | else | |
1214 | { | |
1215 | base = get_ref_base_and_extent (lhs, &offset, &size, &max_size); | |
aa803cc7 JH |
1216 | if (DECL_P (tci->instance)) |
1217 | { | |
1218 | if (base != tci->instance) | |
1219 | { | |
1220 | if (dump_file) | |
1221 | { | |
1222 | fprintf (dump_file, " base:"); | |
1223 | print_generic_expr (dump_file, base, TDF_SLIM); | |
1224 | fprintf (dump_file, " does not match instance:"); | |
1225 | print_generic_expr (dump_file, tci->instance, TDF_SLIM); | |
1226 | fprintf (dump_file, "\n"); | |
1227 | } | |
1228 | return NULL_TREE; | |
1229 | } | |
1230 | } | |
1231 | else if (TREE_CODE (base) == MEM_REF) | |
1232 | { | |
1184bb78 | 1233 | if (!operand_equal_p (tci->instance, TREE_OPERAND (base, 0), 0)) |
aa803cc7 JH |
1234 | { |
1235 | if (dump_file) | |
1236 | { | |
1237 | fprintf (dump_file, " base mem ref:"); | |
1238 | print_generic_expr (dump_file, base, TDF_SLIM); | |
1184bb78 | 1239 | fprintf (dump_file, " does not match instance:"); |
aa803cc7 JH |
1240 | print_generic_expr (dump_file, tci->instance, TDF_SLIM); |
1241 | fprintf (dump_file, "\n"); | |
1242 | } | |
1243 | return NULL_TREE; | |
1244 | } | |
1184bb78 JH |
1245 | if (!integer_zerop (TREE_OPERAND (base, 1))) |
1246 | { | |
1247 | if (!tree_fits_shwi_p (TREE_OPERAND (base, 1))) | |
1248 | { | |
1249 | if (dump_file) | |
1250 | { | |
1251 | fprintf (dump_file, " base mem ref:"); | |
1252 | print_generic_expr (dump_file, base, TDF_SLIM); | |
1253 | fprintf (dump_file, " has non-representable offset:"); | |
1254 | print_generic_expr (dump_file, tci->instance, TDF_SLIM); | |
1255 | fprintf (dump_file, "\n"); | |
1256 | } | |
1257 | return NULL_TREE; | |
1258 | } | |
1259 | else | |
1260 | offset += tree_to_shwi (TREE_OPERAND (base, 1)) * BITS_PER_UNIT; | |
1261 | } | |
aa803cc7 JH |
1262 | } |
1263 | else if (!operand_equal_p (tci->instance, base, 0) | |
1264 | || tci->offset) | |
1265 | { | |
1266 | if (dump_file) | |
1267 | { | |
1268 | fprintf (dump_file, " base:"); | |
1269 | print_generic_expr (dump_file, base, TDF_SLIM); | |
1270 | fprintf (dump_file, " does not match instance:"); | |
1271 | print_generic_expr (dump_file, tci->instance, TDF_SLIM); | |
1272 | fprintf (dump_file, " with offset %i\n", (int)tci->offset); | |
1273 | } | |
b30df7b6 | 1274 | return tci->offset > POINTER_SIZE ? error_mark_node : NULL_TREE; |
1184bb78 JH |
1275 | } |
1276 | if (offset != tci->offset | |
1277 | || size != POINTER_SIZE | |
1278 | || max_size != POINTER_SIZE) | |
1279 | { | |
1280 | if (dump_file) | |
1281 | fprintf (dump_file, " wrong offset %i!=%i or size %i\n", | |
1282 | (int)offset, (int)tci->offset, (int)size); | |
b30df7b6 | 1283 | return offset + POINTER_SIZE <= tci->offset |
1184bb78 | 1284 | || (max_size != -1 |
b30df7b6 | 1285 | && tci->offset + POINTER_SIZE > offset + max_size) |
1184bb78 | 1286 | ? error_mark_node : NULL; |
aa803cc7 JH |
1287 | } |
1288 | } | |
1289 | ||
1290 | tree vtable; | |
1291 | unsigned HOST_WIDE_INT offset2; | |
1292 | ||
1293 | if (!vtable_pointer_value_to_vtable (rhs, &vtable, &offset2)) | |
1294 | { | |
1295 | if (dump_file) | |
1296 | fprintf (dump_file, " Failed to lookup binfo\n"); | |
1297 | return NULL; | |
1298 | } | |
1299 | ||
1300 | tree binfo = subbinfo_with_vtable_at_offset (TYPE_BINFO (DECL_CONTEXT (vtable)), | |
1301 | offset2, vtable); | |
1302 | if (!binfo) | |
1303 | { | |
1304 | if (dump_file) | |
1305 | fprintf (dump_file, " Construction vtable used\n"); | |
67a1b94c | 1306 | /* FIXME: We should suport construction contexts. */ |
aa803cc7 JH |
1307 | return NULL; |
1308 | } | |
1309 | ||
1310 | *type_offset = tree_to_shwi (BINFO_OFFSET (binfo)) * BITS_PER_UNIT; | |
1311 | return DECL_CONTEXT (vtable); | |
1312 | } | |
1313 | ||
1314 | /* Record dynamic type change of TCI to TYPE. */ | |
1315 | ||
1316 | static void | |
1317 | record_known_type (struct type_change_info *tci, tree type, HOST_WIDE_INT offset) | |
1318 | { | |
1319 | if (dump_file) | |
1320 | { | |
1321 | if (type) | |
1322 | { | |
1323 | fprintf (dump_file, " Recording type: "); | |
1324 | print_generic_expr (dump_file, type, TDF_SLIM); | |
1325 | fprintf (dump_file, " at offset %i\n", (int)offset); | |
1326 | } | |
1327 | else | |
1328 | fprintf (dump_file, " Recording unknown type\n"); | |
1329 | } | |
1330 | ||
1331 | /* If we found a constructor of type that is not polymorphic or | |
1332 | that may contain the type in question as a field (not as base), | |
1333 | restrict to the inner class first to make type matching bellow | |
1334 | happier. */ | |
1335 | if (type | |
1336 | && (offset | |
1337 | || (TREE_CODE (type) != RECORD_TYPE | |
1be0e58d | 1338 | || !TYPE_BINFO (type) |
aa803cc7 JH |
1339 | || !polymorphic_type_binfo_p (TYPE_BINFO (type))))) |
1340 | { | |
1341 | ipa_polymorphic_call_context context; | |
1342 | ||
1343 | context.offset = offset; | |
1344 | context.outer_type = type; | |
1345 | context.maybe_in_construction = false; | |
1346 | context.maybe_derived_type = false; | |
4081ada2 | 1347 | context.dynamic = true; |
aa803cc7 JH |
1348 | /* If we failed to find the inner type, we know that the call |
1349 | would be undefined for type produced here. */ | |
1350 | if (!context.restrict_to_inner_class (tci->otr_type)) | |
1351 | { | |
1352 | if (dump_file) | |
1353 | fprintf (dump_file, " Ignoring; does not contain otr_type\n"); | |
1354 | return; | |
1355 | } | |
1356 | /* Watch for case we reached an POD type and anticipate placement | |
1357 | new. */ | |
1358 | if (!context.maybe_derived_type) | |
1359 | { | |
1360 | type = context.outer_type; | |
1361 | offset = context.offset; | |
1362 | } | |
1363 | } | |
1364 | if (tci->type_maybe_changed | |
1365 | && (!types_same_for_odr (type, tci->known_current_type) | |
1366 | || offset != tci->known_current_offset)) | |
1367 | tci->multiple_types_encountered = true; | |
1368 | tci->known_current_type = TYPE_MAIN_VARIANT (type); | |
1369 | tci->known_current_offset = offset; | |
1370 | tci->type_maybe_changed = true; | |
1371 | } | |
1372 | ||
1373 | /* Callback of walk_aliased_vdefs and a helper function for | |
1374 | detect_type_change to check whether a particular statement may modify | |
1375 | the virtual table pointer, and if possible also determine the new type of | |
1376 | the (sub-)object. It stores its result into DATA, which points to a | |
1377 | type_change_info structure. */ | |
1378 | ||
1379 | static bool | |
1380 | check_stmt_for_type_change (ao_ref *ao ATTRIBUTE_UNUSED, tree vdef, void *data) | |
1381 | { | |
1382 | gimple stmt = SSA_NAME_DEF_STMT (vdef); | |
1383 | struct type_change_info *tci = (struct type_change_info *) data; | |
1384 | tree fn; | |
1385 | ||
1386 | /* If we already gave up, just terminate the rest of walk. */ | |
1387 | if (tci->multiple_types_encountered) | |
1388 | return true; | |
1389 | ||
1390 | if (is_gimple_call (stmt)) | |
1391 | { | |
1392 | if (gimple_call_flags (stmt) & (ECF_CONST | ECF_PURE)) | |
1393 | return false; | |
1394 | ||
1395 | /* Check for a constructor call. */ | |
1396 | if ((fn = gimple_call_fndecl (stmt)) != NULL_TREE | |
1397 | && DECL_CXX_CONSTRUCTOR_P (fn) | |
1398 | && TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE | |
1399 | && gimple_call_num_args (stmt)) | |
1400 | { | |
1401 | tree op = walk_ssa_copies (gimple_call_arg (stmt, 0)); | |
70e7f2a2 | 1402 | tree type = TYPE_METHOD_BASETYPE (TREE_TYPE (fn)); |
aa803cc7 JH |
1403 | HOST_WIDE_INT offset = 0, size, max_size; |
1404 | ||
1405 | if (dump_file) | |
1406 | { | |
1407 | fprintf (dump_file, " Checking constructor call: "); | |
1408 | print_gimple_stmt (dump_file, stmt, 0, 0); | |
1409 | } | |
1410 | ||
1411 | /* See if THIS parameter seems like instance pointer. */ | |
1412 | if (TREE_CODE (op) == ADDR_EXPR) | |
1413 | { | |
1414 | op = get_ref_base_and_extent (TREE_OPERAND (op, 0), | |
1415 | &offset, &size, &max_size); | |
1416 | if (size != max_size || max_size == -1) | |
1417 | { | |
1418 | tci->speculative = true; | |
1419 | return false; | |
1420 | } | |
1421 | if (op && TREE_CODE (op) == MEM_REF) | |
1422 | { | |
1423 | if (!tree_fits_shwi_p (TREE_OPERAND (op, 1))) | |
1424 | { | |
1425 | tci->speculative = true; | |
1426 | return false; | |
1427 | } | |
1428 | offset += tree_to_shwi (TREE_OPERAND (op, 1)) | |
1429 | * BITS_PER_UNIT; | |
1430 | op = TREE_OPERAND (op, 0); | |
1431 | } | |
1432 | else if (DECL_P (op)) | |
1433 | ; | |
1434 | else | |
1435 | { | |
1436 | tci->speculative = true; | |
1437 | return false; | |
1438 | } | |
1439 | op = walk_ssa_copies (op); | |
1440 | } | |
1441 | if (operand_equal_p (op, tci->instance, 0) | |
1442 | && TYPE_SIZE (type) | |
1443 | && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST | |
1444 | && tree_fits_shwi_p (TYPE_SIZE (type)) | |
1445 | && tree_to_shwi (TYPE_SIZE (type)) + offset > tci->offset) | |
1446 | { | |
1447 | record_known_type (tci, type, tci->offset - offset); | |
1448 | return true; | |
1449 | } | |
1450 | } | |
1451 | /* Calls may possibly change dynamic type by placement new. Assume | |
1452 | it will not happen, but make result speculative only. */ | |
1453 | if (dump_file) | |
1454 | { | |
1455 | fprintf (dump_file, " Function call may change dynamic type:"); | |
1456 | print_gimple_stmt (dump_file, stmt, 0, 0); | |
1457 | } | |
1458 | tci->speculative = true; | |
1459 | return false; | |
1460 | } | |
1461 | /* Check for inlined virtual table store. */ | |
1462 | else if (noncall_stmt_may_be_vtbl_ptr_store (stmt)) | |
1463 | { | |
1464 | tree type; | |
1465 | HOST_WIDE_INT offset = 0; | |
1466 | if (dump_file) | |
1467 | { | |
1468 | fprintf (dump_file, " Checking vtbl store: "); | |
1469 | print_gimple_stmt (dump_file, stmt, 0, 0); | |
1470 | } | |
1471 | ||
1472 | type = extr_type_from_vtbl_ptr_store (stmt, tci, &offset); | |
1184bb78 JH |
1473 | if (type == error_mark_node) |
1474 | return false; | |
94c4084c | 1475 | gcc_assert (!type || TYPE_MAIN_VARIANT (type) == type); |
aa803cc7 JH |
1476 | if (!type) |
1477 | { | |
1478 | if (dump_file) | |
1479 | fprintf (dump_file, " Unanalyzed store may change type.\n"); | |
1480 | tci->seen_unanalyzed_store = true; | |
1481 | tci->speculative = true; | |
1482 | } | |
1483 | else | |
1484 | record_known_type (tci, type, offset); | |
1485 | return true; | |
1486 | } | |
1487 | else | |
1488 | return false; | |
1489 | } | |
1490 | ||
1491 | /* THIS is polymorphic call context obtained from get_polymorphic_context. | |
1492 | OTR_OBJECT is pointer to the instance returned by OBJ_TYPE_REF_OBJECT. | |
1493 | INSTANCE is pointer to the outer instance as returned by | |
1494 | get_polymorphic_context. To avoid creation of temporary expressions, | |
1495 | INSTANCE may also be an declaration of get_polymorphic_context found the | |
1496 | value to be in static storage. | |
1497 | ||
1498 | If the type of instance is not fully determined | |
1499 | (either OUTER_TYPE is unknown or MAYBE_IN_CONSTRUCTION/INCLUDE_DERIVED_TYPES | |
1500 | is set), try to walk memory writes and find the actual construction of the | |
1501 | instance. | |
1502 | ||
0127c169 JH |
1503 | Return true if memory is unchanged from function entry. |
1504 | ||
aa803cc7 JH |
1505 | We do not include this analysis in the context analysis itself, because |
1506 | it needs memory SSA to be fully built and the walk may be expensive. | |
1507 | So it is not suitable for use withing fold_stmt and similar uses. */ | |
1508 | ||
1509 | bool | |
1510 | ipa_polymorphic_call_context::get_dynamic_type (tree instance, | |
1511 | tree otr_object, | |
1512 | tree otr_type, | |
1513 | gimple call) | |
1514 | { | |
1515 | struct type_change_info tci; | |
1516 | ao_ref ao; | |
1517 | bool function_entry_reached = false; | |
1518 | tree instance_ref = NULL; | |
1519 | gimple stmt = call; | |
1520 | /* Remember OFFSET before it is modified by restrict_to_inner_class. | |
1521 | This is because we do not update INSTANCE when walking inwards. */ | |
1522 | HOST_WIDE_INT instance_offset = offset; | |
1523 | ||
049e6d36 JH |
1524 | if (otr_type) |
1525 | otr_type = TYPE_MAIN_VARIANT (otr_type); | |
aa803cc7 JH |
1526 | |
1527 | /* Walk into inner type. This may clear maybe_derived_type and save us | |
1528 | from useless work. It also makes later comparsions with static type | |
1529 | easier. */ | |
049e6d36 | 1530 | if (outer_type && otr_type) |
aa803cc7 JH |
1531 | { |
1532 | if (!restrict_to_inner_class (otr_type)) | |
1533 | return false; | |
1534 | } | |
1535 | ||
1536 | if (!maybe_in_construction && !maybe_derived_type) | |
1537 | return false; | |
1538 | ||
1539 | /* We need to obtain refernce to virtual table pointer. It is better | |
1540 | to look it up in the code rather than build our own. This require bit | |
1541 | of pattern matching, but we end up verifying that what we found is | |
1542 | correct. | |
1543 | ||
1544 | What we pattern match is: | |
1545 | ||
1546 | tmp = instance->_vptr.A; // vtbl ptr load | |
1547 | tmp2 = tmp[otr_token]; // vtable lookup | |
1548 | OBJ_TYPE_REF(tmp2;instance->0) (instance); | |
1549 | ||
1550 | We want to start alias oracle walk from vtbl pointer load, | |
1551 | but we may not be able to identify it, for example, when PRE moved the | |
1552 | load around. */ | |
1553 | ||
1554 | if (gimple_code (call) == GIMPLE_CALL) | |
1555 | { | |
1556 | tree ref = gimple_call_fn (call); | |
1557 | HOST_WIDE_INT offset2, size, max_size; | |
1558 | ||
1559 | if (TREE_CODE (ref) == OBJ_TYPE_REF) | |
1560 | { | |
1561 | ref = OBJ_TYPE_REF_EXPR (ref); | |
1562 | ref = walk_ssa_copies (ref); | |
1563 | ||
1564 | /* Check if definition looks like vtable lookup. */ | |
1565 | if (TREE_CODE (ref) == SSA_NAME | |
1566 | && !SSA_NAME_IS_DEFAULT_DEF (ref) | |
1567 | && gimple_assign_load_p (SSA_NAME_DEF_STMT (ref)) | |
1568 | && TREE_CODE (gimple_assign_rhs1 | |
1569 | (SSA_NAME_DEF_STMT (ref))) == MEM_REF) | |
1570 | { | |
1571 | ref = get_base_address | |
1572 | (TREE_OPERAND (gimple_assign_rhs1 | |
1573 | (SSA_NAME_DEF_STMT (ref)), 0)); | |
1574 | ref = walk_ssa_copies (ref); | |
1575 | /* Find base address of the lookup and see if it looks like | |
1576 | vptr load. */ | |
1577 | if (TREE_CODE (ref) == SSA_NAME | |
1578 | && !SSA_NAME_IS_DEFAULT_DEF (ref) | |
1579 | && gimple_assign_load_p (SSA_NAME_DEF_STMT (ref))) | |
1580 | { | |
1581 | tree ref_exp = gimple_assign_rhs1 (SSA_NAME_DEF_STMT (ref)); | |
1582 | tree base_ref = get_ref_base_and_extent | |
1583 | (ref_exp, &offset2, &size, &max_size); | |
1584 | ||
1585 | /* Finally verify that what we found looks like read from OTR_OBJECT | |
1586 | or from INSTANCE with offset OFFSET. */ | |
1587 | if (base_ref | |
1588 | && ((TREE_CODE (base_ref) == MEM_REF | |
1589 | && ((offset2 == instance_offset | |
1590 | && TREE_OPERAND (base_ref, 0) == instance) | |
1591 | || (!offset2 && TREE_OPERAND (base_ref, 0) == otr_object))) | |
1592 | || (DECL_P (instance) && base_ref == instance | |
1593 | && offset2 == instance_offset))) | |
1594 | { | |
1595 | stmt = SSA_NAME_DEF_STMT (ref); | |
1596 | instance_ref = ref_exp; | |
1597 | } | |
1598 | } | |
1599 | } | |
1600 | } | |
1601 | } | |
1602 | ||
1603 | /* If we failed to look up the refernece in code, build our own. */ | |
1604 | if (!instance_ref) | |
1605 | { | |
1606 | /* If the statement in question does not use memory, we can't tell | |
1607 | anything. */ | |
1608 | if (!gimple_vuse (stmt)) | |
1609 | return false; | |
1610 | ao_ref_init_from_ptr_and_size (&ao, otr_object, NULL); | |
1611 | } | |
1612 | else | |
1613 | /* Otherwise use the real reference. */ | |
1614 | ao_ref_init (&ao, instance_ref); | |
1615 | ||
1616 | /* We look for vtbl pointer read. */ | |
1617 | ao.size = POINTER_SIZE; | |
1618 | ao.max_size = ao.size; | |
049e6d36 JH |
1619 | if (otr_type) |
1620 | ao.ref_alias_set | |
1621 | = get_deref_alias_set (TREE_TYPE (BINFO_VTABLE (TYPE_BINFO (otr_type)))); | |
aa803cc7 JH |
1622 | |
1623 | if (dump_file) | |
1624 | { | |
1625 | fprintf (dump_file, "Determining dynamic type for call: "); | |
1626 | print_gimple_stmt (dump_file, call, 0, 0); | |
1627 | fprintf (dump_file, " Starting walk at: "); | |
1628 | print_gimple_stmt (dump_file, stmt, 0, 0); | |
1629 | fprintf (dump_file, " instance pointer: "); | |
1630 | print_generic_expr (dump_file, otr_object, TDF_SLIM); | |
1631 | fprintf (dump_file, " Outer instance pointer: "); | |
1632 | print_generic_expr (dump_file, instance, TDF_SLIM); | |
1633 | fprintf (dump_file, " offset: %i (bits)", (int)offset); | |
1634 | fprintf (dump_file, " vtbl reference: "); | |
1635 | print_generic_expr (dump_file, instance_ref, TDF_SLIM); | |
1636 | fprintf (dump_file, "\n"); | |
1637 | } | |
1638 | ||
1639 | tci.offset = offset; | |
1640 | tci.instance = instance; | |
1641 | tci.vtbl_ptr_ref = instance_ref; | |
1642 | gcc_assert (TREE_CODE (instance) != MEM_REF); | |
1643 | tci.known_current_type = NULL_TREE; | |
1644 | tci.known_current_offset = 0; | |
1645 | tci.otr_type = otr_type; | |
1646 | tci.type_maybe_changed = false; | |
1647 | tci.multiple_types_encountered = false; | |
1648 | tci.speculative = false; | |
1649 | tci.seen_unanalyzed_store = false; | |
1650 | ||
1651 | walk_aliased_vdefs (&ao, gimple_vuse (stmt), check_stmt_for_type_change, | |
1652 | &tci, NULL, &function_entry_reached); | |
1653 | ||
1654 | /* If we did not find any type changing statements, we may still drop | |
1655 | maybe_in_construction flag if the context already have outer type. | |
1656 | ||
1657 | Here we make special assumptions about both constructors and | |
1658 | destructors which are all the functions that are allowed to alter the | |
1659 | VMT pointers. It assumes that destructors begin with assignment into | |
1660 | all VMT pointers and that constructors essentially look in the | |
1661 | following way: | |
1662 | ||
1663 | 1) The very first thing they do is that they call constructors of | |
1664 | ancestor sub-objects that have them. | |
1665 | ||
1666 | 2) Then VMT pointers of this and all its ancestors is set to new | |
1667 | values corresponding to the type corresponding to the constructor. | |
1668 | ||
1669 | 3) Only afterwards, other stuff such as constructor of member | |
1670 | sub-objects and the code written by the user is run. Only this may | |
1671 | include calling virtual functions, directly or indirectly. | |
1672 | ||
1673 | 4) placement new can not be used to change type of non-POD statically | |
1674 | allocated variables. | |
1675 | ||
1676 | There is no way to call a constructor of an ancestor sub-object in any | |
1677 | other way. | |
1678 | ||
1679 | This means that we do not have to care whether constructors get the | |
1680 | correct type information because they will always change it (in fact, | |
1681 | if we define the type to be given by the VMT pointer, it is undefined). | |
1682 | ||
1683 | The most important fact to derive from the above is that if, for some | |
1684 | statement in the section 3, we try to detect whether the dynamic type | |
1685 | has changed, we can safely ignore all calls as we examine the function | |
1686 | body backwards until we reach statements in section 2 because these | |
1687 | calls cannot be ancestor constructors or destructors (if the input is | |
1688 | not bogus) and so do not change the dynamic type (this holds true only | |
1689 | for automatically allocated objects but at the moment we devirtualize | |
1690 | only these). We then must detect that statements in section 2 change | |
1691 | the dynamic type and can try to derive the new type. That is enough | |
1692 | and we can stop, we will never see the calls into constructors of | |
1693 | sub-objects in this code. | |
1694 | ||
1695 | Therefore if the static outer type was found (outer_type) | |
1696 | we can safely ignore tci.speculative that is set on calls and give up | |
1697 | only if there was dyanmic type store that may affect given variable | |
1698 | (seen_unanalyzed_store) */ | |
1699 | ||
1700 | if (!tci.type_maybe_changed | |
1701 | || (outer_type | |
4081ada2 | 1702 | && !dynamic |
aa803cc7 JH |
1703 | && !tci.seen_unanalyzed_store |
1704 | && !tci.multiple_types_encountered | |
1705 | && offset == tci.offset | |
1706 | && types_same_for_odr (tci.known_current_type, | |
1707 | outer_type))) | |
1708 | { | |
1709 | if (!outer_type || tci.seen_unanalyzed_store) | |
1710 | return false; | |
1711 | if (maybe_in_construction) | |
1712 | maybe_in_construction = false; | |
1713 | if (dump_file) | |
1714 | fprintf (dump_file, " No dynamic type change found.\n"); | |
1715 | return true; | |
1716 | } | |
1717 | ||
1718 | if (tci.known_current_type | |
1719 | && !function_entry_reached | |
1720 | && !tci.multiple_types_encountered) | |
1721 | { | |
1722 | if (!tci.speculative) | |
1723 | { | |
1724 | outer_type = TYPE_MAIN_VARIANT (tci.known_current_type); | |
1725 | offset = tci.known_current_offset; | |
4081ada2 | 1726 | dynamic = true; |
aa803cc7 JH |
1727 | maybe_in_construction = false; |
1728 | maybe_derived_type = false; | |
1729 | if (dump_file) | |
1730 | fprintf (dump_file, " Determined dynamic type.\n"); | |
1731 | } | |
1732 | else if (!speculative_outer_type | |
1733 | || speculative_maybe_derived_type) | |
1734 | { | |
1735 | speculative_outer_type = TYPE_MAIN_VARIANT (tci.known_current_type); | |
1736 | speculative_offset = tci.known_current_offset; | |
1737 | speculative_maybe_derived_type = false; | |
1738 | if (dump_file) | |
1739 | fprintf (dump_file, " Determined speculative dynamic type.\n"); | |
1740 | } | |
1741 | } | |
1742 | else if (dump_file) | |
1743 | { | |
1744 | fprintf (dump_file, " Found multiple types%s%s\n", | |
1745 | function_entry_reached ? " (function entry reached)" : "", | |
1746 | function_entry_reached ? " (multiple types encountered)" : ""); | |
1747 | } | |
1748 | ||
0127c169 | 1749 | return false; |
aa803cc7 JH |
1750 | } |
1751 | ||
67a1b94c JH |
1752 | /* See if speculation given by SPEC_OUTER_TYPE, SPEC_OFFSET and SPEC_MAYBE_DERIVED_TYPE |
1753 | seems consistent (and useful) with what we already have in the non-speculative context. */ | |
1754 | ||
1755 | bool | |
1756 | ipa_polymorphic_call_context::speculation_consistent_p (tree spec_outer_type, | |
1757 | HOST_WIDE_INT spec_offset, | |
1758 | bool spec_maybe_derived_type, | |
df0d8136 | 1759 | tree otr_type) const |
67a1b94c JH |
1760 | { |
1761 | if (!flag_devirtualize_speculatively) | |
1762 | return false; | |
4081ada2 JH |
1763 | |
1764 | /* Non-polymorphic types are useless for deriving likely polymorphic | |
1765 | call targets. */ | |
1766 | if (!spec_outer_type || !contains_polymorphic_type_p (spec_outer_type)) | |
1767 | return false; | |
1768 | ||
67a1b94c JH |
1769 | /* If we know nothing, speculation is always good. */ |
1770 | if (!outer_type) | |
1771 | return true; | |
1772 | ||
1773 | /* Speculation is only useful to avoid derived types. | |
1774 | This is not 100% true for placement new, where the outer context may | |
1775 | turn out to be useless, but ignore these for now. */ | |
1776 | if (!maybe_derived_type) | |
1777 | return false; | |
1778 | ||
1779 | /* If types agrees, speculation is consistent, but it makes sense only | |
1780 | when it says something new. */ | |
1781 | if (types_must_be_same_for_odr (spec_outer_type, outer_type)) | |
1782 | return maybe_derived_type && !spec_maybe_derived_type; | |
1783 | ||
67a1b94c JH |
1784 | /* If speculation does not contain the type in question, ignore it. */ |
1785 | if (otr_type | |
1786 | && !contains_type_p (spec_outer_type, spec_offset, otr_type, false, true)) | |
1787 | return false; | |
1788 | ||
1789 | /* If outer type already contains speculation as a filed, | |
1790 | it is useless. We already know from OUTER_TYPE | |
1791 | SPEC_TYPE and that it is not in the construction. */ | |
1792 | if (contains_type_p (outer_type, offset - spec_offset, | |
1793 | spec_outer_type, false, false)) | |
1794 | return false; | |
1795 | ||
1796 | /* If speculative outer type is not more specified than outer | |
1797 | type, just give up. | |
1798 | We can only decide this safely if we can compare types with OUTER_TYPE. | |
1799 | */ | |
1800 | if ((!in_lto_p || odr_type_p (outer_type)) | |
1801 | && !contains_type_p (spec_outer_type, | |
1802 | spec_offset - offset, | |
1803 | outer_type, false)) | |
1804 | return false; | |
1805 | return true; | |
1806 | } | |
1807 | ||
1808 | /* Improve THIS with speculation described by NEW_OUTER_TYPE, NEW_OFFSET, | |
1809 | NEW_MAYBE_DERIVED_TYPE | |
1810 | If OTR_TYPE is set, assume the context is used with OTR_TYPE. */ | |
1811 | ||
1812 | bool | |
1813 | ipa_polymorphic_call_context::combine_speculation_with | |
1814 | (tree new_outer_type, HOST_WIDE_INT new_offset, bool new_maybe_derived_type, | |
1815 | tree otr_type) | |
1816 | { | |
1817 | if (!new_outer_type) | |
1818 | return false; | |
1819 | ||
1820 | /* restrict_to_inner_class may eliminate wrong speculation making our job | |
1821 | easeier. */ | |
1822 | if (otr_type) | |
1823 | restrict_to_inner_class (otr_type); | |
1824 | ||
1825 | if (!speculation_consistent_p (new_outer_type, new_offset, | |
1826 | new_maybe_derived_type, otr_type)) | |
1827 | return false; | |
1828 | ||
1829 | /* New speculation is a win in case we have no speculation or new | |
1830 | speculation does not consider derivations. */ | |
1831 | if (!speculative_outer_type | |
1832 | || (speculative_maybe_derived_type | |
1833 | && !new_maybe_derived_type)) | |
1834 | { | |
1835 | speculative_outer_type = new_outer_type; | |
1836 | speculative_offset = new_offset; | |
1837 | speculative_maybe_derived_type = new_maybe_derived_type; | |
1838 | return true; | |
1839 | } | |
1840 | else if (types_must_be_same_for_odr (speculative_outer_type, | |
1841 | new_outer_type)) | |
1842 | { | |
1843 | if (speculative_offset != new_offset) | |
1844 | { | |
1845 | /* OK we have two contexts that seems valid but they disagree, | |
1846 | just give up. | |
1847 | ||
1848 | This is not a lattice operation, so we may want to drop it later. */ | |
1849 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1850 | fprintf (dump_file, | |
1851 | "Speculative outer types match, " | |
1852 | "offset mismatch -> invalid speculation\n"); | |
1853 | clear_speculation (); | |
1854 | return true; | |
1855 | } | |
1856 | else | |
1857 | { | |
1858 | if (speculative_maybe_derived_type && !new_maybe_derived_type) | |
1859 | { | |
1860 | speculative_maybe_derived_type = false; | |
1861 | return true; | |
1862 | } | |
1863 | else | |
1864 | return false; | |
1865 | } | |
1866 | } | |
1867 | /* Choose type that contains the other. This one either contains the outer | |
1868 | as a field (thus giving exactly one target) or is deeper in the type | |
1869 | hiearchy. */ | |
1870 | else if (speculative_outer_type | |
1871 | && speculative_maybe_derived_type | |
1872 | && (new_offset > speculative_offset | |
1873 | || (new_offset == speculative_offset | |
1874 | && contains_type_p (new_outer_type, | |
1875 | 0, speculative_outer_type, false)))) | |
1876 | { | |
1877 | tree old_outer_type = speculative_outer_type; | |
1878 | HOST_WIDE_INT old_offset = speculative_offset; | |
1879 | bool old_maybe_derived_type = speculative_maybe_derived_type; | |
1880 | ||
1881 | speculative_outer_type = new_outer_type; | |
1882 | speculative_offset = new_offset; | |
1883 | speculative_maybe_derived_type = new_maybe_derived_type; | |
1884 | ||
1885 | if (otr_type) | |
1886 | restrict_to_inner_class (otr_type); | |
1887 | ||
1888 | /* If the speculation turned out to make no sense, revert to sensible | |
1889 | one. */ | |
1890 | if (!speculative_outer_type) | |
1891 | { | |
1892 | speculative_outer_type = old_outer_type; | |
1893 | speculative_offset = old_offset; | |
1894 | speculative_maybe_derived_type = old_maybe_derived_type; | |
1895 | return false; | |
1896 | } | |
1897 | return (old_offset != speculative_offset | |
1898 | || old_maybe_derived_type != speculative_maybe_derived_type | |
1899 | || types_must_be_same_for_odr (speculative_outer_type, | |
1900 | new_outer_type)); | |
1901 | } | |
1902 | return false; | |
1903 | } | |
1904 | ||
df0d8136 JH |
1905 | /* Make speculation less specific so |
1906 | NEW_OUTER_TYPE, NEW_OFFSET, NEW_MAYBE_DERIVED_TYPE is also included. | |
1907 | If OTR_TYPE is set, assume the context is used with OTR_TYPE. */ | |
1908 | ||
1909 | bool | |
1910 | ipa_polymorphic_call_context::meet_speculation_with | |
1911 | (tree new_outer_type, HOST_WIDE_INT new_offset, bool new_maybe_derived_type, | |
1912 | tree otr_type) | |
1913 | { | |
1914 | if (!new_outer_type && speculative_outer_type) | |
1915 | { | |
1916 | clear_speculation (); | |
1917 | return true; | |
1918 | } | |
1919 | ||
1920 | /* restrict_to_inner_class may eliminate wrong speculation making our job | |
1921 | easeier. */ | |
1922 | if (otr_type) | |
1923 | restrict_to_inner_class (otr_type); | |
1924 | ||
1925 | if (!speculative_outer_type | |
1926 | || !speculation_consistent_p (speculative_outer_type, | |
1927 | speculative_offset, | |
1928 | speculative_maybe_derived_type, | |
1929 | otr_type)) | |
1930 | return false; | |
1931 | ||
1932 | if (!speculation_consistent_p (new_outer_type, new_offset, | |
1933 | new_maybe_derived_type, otr_type)) | |
1934 | { | |
1935 | clear_speculation (); | |
1936 | return true; | |
1937 | } | |
1938 | ||
1939 | else if (types_must_be_same_for_odr (speculative_outer_type, | |
1940 | new_outer_type)) | |
1941 | { | |
1942 | if (speculative_offset != new_offset) | |
1943 | { | |
1944 | clear_speculation (); | |
1945 | return true; | |
1946 | } | |
1947 | else | |
1948 | { | |
1949 | if (!speculative_maybe_derived_type && new_maybe_derived_type) | |
1950 | { | |
1951 | speculative_maybe_derived_type = true; | |
1952 | return true; | |
1953 | } | |
1954 | else | |
1955 | return false; | |
1956 | } | |
1957 | } | |
1958 | /* See if one type contains the other as a field (not base). */ | |
1959 | else if (contains_type_p (new_outer_type, new_offset - speculative_offset, | |
1960 | speculative_outer_type, false, false)) | |
1961 | return false; | |
1962 | else if (contains_type_p (speculative_outer_type, | |
1963 | speculative_offset - new_offset, | |
1964 | new_outer_type, false, false)) | |
1965 | { | |
1966 | speculative_outer_type = new_outer_type; | |
1967 | speculative_offset = new_offset; | |
1968 | speculative_maybe_derived_type = new_maybe_derived_type; | |
1969 | return true; | |
1970 | } | |
1971 | /* See if OUTER_TYPE is base of CTX.OUTER_TYPE. */ | |
1972 | else if (contains_type_p (new_outer_type, | |
1973 | new_offset - speculative_offset, | |
1974 | speculative_outer_type, false, true)) | |
1975 | { | |
1976 | if (!speculative_maybe_derived_type) | |
1977 | { | |
1978 | speculative_maybe_derived_type = true; | |
1979 | return true; | |
1980 | } | |
1981 | return false; | |
1982 | } | |
1983 | /* See if CTX.OUTER_TYPE is base of OUTER_TYPE. */ | |
1984 | else if (contains_type_p (speculative_outer_type, | |
1985 | speculative_offset - new_offset, new_outer_type, false, true)) | |
1986 | { | |
1987 | speculative_outer_type = new_outer_type; | |
1988 | speculative_offset = new_offset; | |
1989 | speculative_maybe_derived_type = true; | |
1990 | return true; | |
1991 | } | |
1992 | else | |
1993 | { | |
1994 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1995 | fprintf (dump_file, "Giving up on speculative meet\n"); | |
1996 | clear_speculation (); | |
1997 | return true; | |
1998 | } | |
1999 | } | |
2000 | ||
67a1b94c JH |
2001 | /* Assume that both THIS and a given context is valid and strenghten THIS |
2002 | if possible. Return true if any strenghtening was made. | |
2003 | If actual type the context is being used in is known, OTR_TYPE should be | |
2004 | set accordingly. This improves quality of combined result. */ | |
2005 | ||
2006 | bool | |
2007 | ipa_polymorphic_call_context::combine_with (ipa_polymorphic_call_context ctx, | |
2008 | tree otr_type) | |
2009 | { | |
2010 | bool updated = false; | |
2011 | ||
2012 | if (ctx.useless_p () || invalid) | |
2013 | return false; | |
2014 | ||
2015 | /* Restricting context to inner type makes merging easier, however do not | |
2016 | do that unless we know how the context is used (OTR_TYPE is non-NULL) */ | |
2017 | if (otr_type && !invalid && !ctx.invalid) | |
2018 | { | |
2019 | restrict_to_inner_class (otr_type); | |
2020 | ctx.restrict_to_inner_class (otr_type); | |
2021 | if(invalid) | |
2022 | return false; | |
2023 | } | |
2024 | ||
2025 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2026 | { | |
2027 | fprintf (dump_file, "Polymorphic call context combine:"); | |
2028 | dump (dump_file); | |
2029 | fprintf (dump_file, "With context: "); | |
2030 | ctx.dump (dump_file); | |
2031 | if (otr_type) | |
2032 | { | |
2033 | fprintf (dump_file, "To be used with type: "); | |
2034 | print_generic_expr (dump_file, otr_type, TDF_SLIM); | |
2035 | fprintf (dump_file, "\n"); | |
2036 | } | |
2037 | } | |
2038 | ||
2039 | /* If call is known to be invalid, we are done. */ | |
2040 | if (ctx.invalid) | |
2041 | { | |
2042 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2043 | fprintf (dump_file, "-> Invalid context\n"); | |
2044 | goto invalidate; | |
2045 | } | |
2046 | ||
2047 | if (!ctx.outer_type) | |
2048 | ; | |
2049 | else if (!outer_type) | |
2050 | { | |
2051 | outer_type = ctx.outer_type; | |
2052 | offset = ctx.offset; | |
4081ada2 | 2053 | dynamic = ctx.dynamic; |
67a1b94c JH |
2054 | maybe_in_construction = ctx.maybe_in_construction; |
2055 | maybe_derived_type = ctx.maybe_derived_type; | |
2056 | updated = true; | |
2057 | } | |
2058 | /* If types are known to be same, merging is quite easy. */ | |
2059 | else if (types_must_be_same_for_odr (outer_type, ctx.outer_type)) | |
2060 | { | |
2061 | if (offset != ctx.offset | |
2062 | && TYPE_SIZE (outer_type) | |
2063 | && TREE_CODE (TYPE_SIZE (outer_type)) == INTEGER_CST) | |
2064 | { | |
2065 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2066 | fprintf (dump_file, "Outer types match, offset mismatch -> invalid\n"); | |
2067 | clear_speculation (); | |
2068 | clear_outer_type (); | |
2069 | invalid = true; | |
2070 | return true; | |
2071 | } | |
2072 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2073 | fprintf (dump_file, "Outer types match, merging flags\n"); | |
2074 | if (maybe_in_construction && !ctx.maybe_in_construction) | |
2075 | { | |
2076 | updated = true; | |
2077 | maybe_in_construction = false; | |
2078 | } | |
2079 | if (maybe_derived_type && !ctx.maybe_derived_type) | |
2080 | { | |
2081 | updated = true; | |
2082 | maybe_derived_type = false; | |
2083 | } | |
4081ada2 JH |
2084 | if (dynamic && !ctx.dynamic) |
2085 | { | |
2086 | updated = true; | |
2087 | dynamic = false; | |
2088 | } | |
67a1b94c JH |
2089 | } |
2090 | /* If we know the type precisely, there is not much to improve. */ | |
2091 | else if (!maybe_derived_type && !maybe_in_construction | |
2092 | && !ctx.maybe_derived_type && !ctx.maybe_in_construction) | |
2093 | { | |
2094 | /* It may be easy to check if second context permits the first | |
2095 | and set INVALID otherwise. This is not easy to do in general; | |
2096 | contains_type_p may return false negatives for non-comparable | |
2097 | types. | |
2098 | ||
2099 | If OTR_TYPE is known, we however can expect that | |
2100 | restrict_to_inner_class should have discovered the same base | |
2101 | type. */ | |
2102 | if (otr_type && !ctx.maybe_in_construction && !ctx.maybe_derived_type) | |
2103 | { | |
2104 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2105 | fprintf (dump_file, "Contextes disagree -> invalid\n"); | |
2106 | goto invalidate; | |
2107 | } | |
2108 | } | |
2109 | /* See if one type contains the other as a field (not base). | |
2110 | In this case we want to choose the wider type, because it contains | |
2111 | more information. */ | |
2112 | else if (contains_type_p (ctx.outer_type, ctx.offset - offset, | |
2113 | outer_type, false, false)) | |
2114 | { | |
2115 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2116 | fprintf (dump_file, "Second type contain the first as a field\n"); | |
2117 | ||
2118 | if (maybe_derived_type) | |
2119 | { | |
2120 | outer_type = ctx.outer_type; | |
2121 | maybe_derived_type = ctx.maybe_derived_type; | |
2122 | offset = ctx.offset; | |
4081ada2 | 2123 | dynamic = ctx.dynamic; |
67a1b94c JH |
2124 | updated = true; |
2125 | } | |
2126 | ||
2127 | /* If we do not know how the context is being used, we can | |
2128 | not clear MAYBE_IN_CONSTRUCTION because it may be offseted | |
2129 | to other component of OUTER_TYPE later and we know nothing | |
2130 | about it. */ | |
2131 | if (otr_type && maybe_in_construction | |
2132 | && !ctx.maybe_in_construction) | |
2133 | { | |
2134 | maybe_in_construction = false; | |
2135 | updated = true; | |
2136 | } | |
2137 | } | |
2138 | else if (contains_type_p (outer_type, offset - ctx.offset, | |
2139 | ctx.outer_type, false, false)) | |
2140 | { | |
2141 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2142 | fprintf (dump_file, "First type contain the second as a field\n"); | |
2143 | ||
2144 | if (otr_type && maybe_in_construction | |
2145 | && !ctx.maybe_in_construction) | |
2146 | { | |
2147 | maybe_in_construction = false; | |
2148 | updated = true; | |
2149 | } | |
2150 | } | |
2151 | /* See if OUTER_TYPE is base of CTX.OUTER_TYPE. */ | |
2152 | else if (contains_type_p (ctx.outer_type, | |
2153 | ctx.offset - offset, outer_type, false, true)) | |
2154 | { | |
2155 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2156 | fprintf (dump_file, "First type is base of second\n"); | |
2157 | if (!maybe_derived_type) | |
2158 | { | |
2159 | if (!ctx.maybe_in_construction | |
2160 | && types_odr_comparable (outer_type, ctx.outer_type)) | |
2161 | { | |
2162 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2163 | fprintf (dump_file, "Second context does not permit base -> invalid\n"); | |
2164 | goto invalidate; | |
2165 | } | |
2166 | } | |
2167 | /* Pick variant deeper in the hiearchy. */ | |
2168 | else | |
2169 | { | |
2170 | outer_type = ctx.outer_type; | |
2171 | maybe_in_construction = ctx.maybe_in_construction; | |
2172 | maybe_derived_type = ctx.maybe_derived_type; | |
2173 | offset = ctx.offset; | |
4081ada2 | 2174 | dynamic = ctx.dynamic; |
67a1b94c JH |
2175 | updated = true; |
2176 | } | |
2177 | } | |
2178 | /* See if CTX.OUTER_TYPE is base of OUTER_TYPE. */ | |
2179 | else if (contains_type_p (outer_type, | |
2180 | offset - ctx.offset, ctx.outer_type, false, true)) | |
2181 | { | |
2182 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2183 | fprintf (dump_file, "Second type is base of first\n"); | |
2184 | if (!ctx.maybe_derived_type) | |
2185 | { | |
2186 | if (!maybe_in_construction | |
2187 | && types_odr_comparable (outer_type, ctx.outer_type)) | |
2188 | { | |
2189 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2190 | fprintf (dump_file, "First context does not permit base -> invalid\n"); | |
2191 | goto invalidate; | |
2192 | } | |
df0d8136 JH |
2193 | /* Pick the base type. */ |
2194 | else if (maybe_in_construction) | |
2195 | { | |
2196 | outer_type = ctx.outer_type; | |
2197 | maybe_in_construction = ctx.maybe_in_construction; | |
2198 | maybe_derived_type = ctx.maybe_derived_type; | |
2199 | offset = ctx.offset; | |
2200 | dynamic = ctx.dynamic; | |
2201 | updated = true; | |
2202 | } | |
67a1b94c JH |
2203 | } |
2204 | } | |
2205 | /* TODO handle merging using hiearchy. */ | |
2206 | else if (dump_file && (dump_flags & TDF_DETAILS)) | |
2207 | fprintf (dump_file, "Giving up on merge\n"); | |
2208 | ||
2209 | updated |= combine_speculation_with (ctx.speculative_outer_type, | |
2210 | ctx.speculative_offset, | |
07f4a83d | 2211 | ctx.speculative_maybe_derived_type, |
67a1b94c JH |
2212 | otr_type); |
2213 | ||
2214 | if (updated && dump_file && (dump_flags & TDF_DETAILS)) | |
2215 | { | |
2216 | fprintf (dump_file, "Updated as: "); | |
2217 | dump (dump_file); | |
2218 | fprintf (dump_file, "\n"); | |
2219 | } | |
2220 | return updated; | |
2221 | ||
2222 | invalidate: | |
2223 | invalid = true; | |
2224 | clear_speculation (); | |
2225 | clear_outer_type (); | |
2226 | return true; | |
2227 | } | |
2228 | ||
2229 | /* Take non-speculative info, merge it with speculative and clear speculation. | |
2230 | Used when we no longer manage to keep track of actual outer type, but we | |
4081ada2 JH |
2231 | think it is still there. |
2232 | ||
2233 | If OTR_TYPE is set, the transformation can be done more effectively assuming | |
2234 | that context is going to be used only that way. */ | |
67a1b94c JH |
2235 | |
2236 | void | |
2237 | ipa_polymorphic_call_context::make_speculative (tree otr_type) | |
2238 | { | |
2239 | tree spec_outer_type = outer_type; | |
2240 | HOST_WIDE_INT spec_offset = offset; | |
2241 | bool spec_maybe_derived_type = maybe_derived_type; | |
2242 | ||
2243 | if (invalid) | |
2244 | { | |
2245 | invalid = false; | |
2246 | clear_outer_type (); | |
2247 | clear_speculation (); | |
2248 | return; | |
2249 | } | |
2250 | if (!outer_type) | |
2251 | return; | |
2252 | clear_outer_type (); | |
2253 | combine_speculation_with (spec_outer_type, spec_offset, | |
2254 | spec_maybe_derived_type, | |
2255 | otr_type); | |
2256 | } | |
4081ada2 JH |
2257 | |
2258 | /* Use when we can not track dynamic type change. This speculatively assume | |
2259 | type change is not happening. */ | |
2260 | ||
2261 | void | |
91e50b2d JH |
2262 | ipa_polymorphic_call_context::possible_dynamic_type_change (bool in_poly_cdtor, |
2263 | tree otr_type) | |
4081ada2 JH |
2264 | { |
2265 | if (dynamic) | |
2266 | make_speculative (otr_type); | |
91e50b2d | 2267 | else if (in_poly_cdtor) |
4081ada2 JH |
2268 | maybe_in_construction = true; |
2269 | } | |
44210a96 MJ |
2270 | |
2271 | /* Return TRUE if this context conveys the same information as OTHER. */ | |
2272 | ||
2273 | bool | |
2274 | ipa_polymorphic_call_context::equal_to | |
2275 | (const ipa_polymorphic_call_context &x) const | |
2276 | { | |
2277 | if (useless_p ()) | |
2278 | return x.useless_p (); | |
2279 | if (invalid) | |
2280 | return x.invalid; | |
2281 | if (x.useless_p () || x.invalid) | |
2282 | return false; | |
2283 | ||
2284 | if (outer_type) | |
2285 | { | |
2286 | if (!x.outer_type | |
2287 | || !types_odr_comparable (outer_type, x.outer_type) | |
2288 | || !types_same_for_odr (outer_type, x.outer_type) | |
2289 | || offset != x.offset | |
2290 | || maybe_in_construction != x.maybe_in_construction | |
2291 | || maybe_derived_type != x.maybe_derived_type | |
2292 | || dynamic != x.dynamic) | |
2293 | return false; | |
2294 | } | |
2295 | else if (x.outer_type) | |
2296 | return false; | |
2297 | ||
df0d8136 JH |
2298 | |
2299 | if (speculative_outer_type | |
2300 | && speculation_consistent_p (speculative_outer_type, speculative_offset, | |
2301 | speculative_maybe_derived_type, NULL_TREE)) | |
44210a96 | 2302 | { |
df0d8136 JH |
2303 | if (!x.speculative_outer_type) |
2304 | return false; | |
2305 | ||
2306 | if (!types_odr_comparable (speculative_outer_type, | |
2307 | x.speculative_outer_type) | |
44210a96 | 2308 | || !types_same_for_odr (speculative_outer_type, |
df0d8136 | 2309 | x.speculative_outer_type) |
44210a96 MJ |
2310 | || speculative_offset != x.speculative_offset |
2311 | || speculative_maybe_derived_type != x.speculative_maybe_derived_type) | |
2312 | return false; | |
2313 | } | |
df0d8136 JH |
2314 | else if (x.speculative_outer_type |
2315 | && x.speculation_consistent_p (x.speculative_outer_type, | |
2316 | x.speculative_offset, | |
2317 | x.speculative_maybe_derived_type, | |
2318 | NULL)) | |
44210a96 MJ |
2319 | return false; |
2320 | ||
2321 | return true; | |
2322 | } | |
df0d8136 JH |
2323 | |
2324 | /* Modify context to be strictly less restrictive than CTX. */ | |
2325 | ||
2326 | bool | |
2327 | ipa_polymorphic_call_context::meet_with (ipa_polymorphic_call_context ctx, | |
2328 | tree otr_type) | |
2329 | { | |
2330 | bool updated = false; | |
2331 | ||
2332 | if (useless_p () || ctx.invalid) | |
2333 | return false; | |
2334 | ||
2335 | /* Restricting context to inner type makes merging easier, however do not | |
2336 | do that unless we know how the context is used (OTR_TYPE is non-NULL) */ | |
2337 | if (otr_type && !useless_p () && !ctx.useless_p ()) | |
2338 | { | |
2339 | restrict_to_inner_class (otr_type); | |
2340 | ctx.restrict_to_inner_class (otr_type); | |
2341 | if(invalid) | |
2342 | return false; | |
2343 | } | |
2344 | ||
2345 | if (equal_to (ctx)) | |
2346 | return false; | |
2347 | ||
2348 | if (ctx.useless_p () || invalid) | |
2349 | { | |
2350 | *this = ctx; | |
2351 | return true; | |
2352 | } | |
2353 | ||
2354 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2355 | { | |
2356 | fprintf (dump_file, "Polymorphic call context meet:"); | |
2357 | dump (dump_file); | |
2358 | fprintf (dump_file, "With context: "); | |
2359 | ctx.dump (dump_file); | |
2360 | if (otr_type) | |
2361 | { | |
2362 | fprintf (dump_file, "To be used with type: "); | |
2363 | print_generic_expr (dump_file, otr_type, TDF_SLIM); | |
2364 | fprintf (dump_file, "\n"); | |
2365 | } | |
2366 | } | |
2367 | ||
2368 | if (!dynamic && ctx.dynamic) | |
2369 | { | |
2370 | dynamic = true; | |
2371 | updated = true; | |
2372 | } | |
2373 | ||
2374 | /* If call is known to be invalid, we are done. */ | |
2375 | if (!outer_type) | |
2376 | ; | |
2377 | else if (!ctx.outer_type) | |
2378 | { | |
2379 | clear_outer_type (); | |
2380 | updated = true; | |
2381 | } | |
2382 | /* If types are known to be same, merging is quite easy. */ | |
2383 | else if (types_must_be_same_for_odr (outer_type, ctx.outer_type)) | |
2384 | { | |
2385 | if (offset != ctx.offset | |
2386 | && TYPE_SIZE (outer_type) | |
2387 | && TREE_CODE (TYPE_SIZE (outer_type)) == INTEGER_CST) | |
2388 | { | |
2389 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2390 | fprintf (dump_file, "Outer types match, offset mismatch -> clearing\n"); | |
2391 | clear_outer_type (); | |
2392 | return true; | |
2393 | } | |
2394 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2395 | fprintf (dump_file, "Outer types match, merging flags\n"); | |
2396 | if (!maybe_in_construction && ctx.maybe_in_construction) | |
2397 | { | |
2398 | updated = true; | |
2399 | maybe_in_construction = true; | |
2400 | } | |
2401 | if (!maybe_derived_type && ctx.maybe_derived_type) | |
2402 | { | |
2403 | updated = true; | |
2404 | maybe_derived_type = true; | |
2405 | } | |
2406 | if (!dynamic && ctx.dynamic) | |
2407 | { | |
2408 | updated = true; | |
2409 | dynamic = true; | |
2410 | } | |
2411 | } | |
2412 | /* See if one type contains the other as a field (not base). */ | |
2413 | else if (contains_type_p (ctx.outer_type, ctx.offset - offset, | |
2414 | outer_type, false, false)) | |
2415 | { | |
2416 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2417 | fprintf (dump_file, "Second type contain the first as a field\n"); | |
2418 | ||
2419 | /* The second type is more specified, so we keep the first. | |
2420 | We need to set DYNAMIC flag to avoid declaring context INVALID | |
2421 | of OFFSET ends up being out of range. */ | |
2422 | if (!dynamic | |
2423 | && (ctx.dynamic | |
2424 | || (!otr_type | |
2425 | && (!TYPE_SIZE (ctx.outer_type) | |
2426 | || !TYPE_SIZE (outer_type) | |
2427 | || !operand_equal_p (TYPE_SIZE (ctx.outer_type), | |
2428 | TYPE_SIZE (outer_type), 0))))) | |
2429 | { | |
2430 | dynamic = true; | |
2431 | updated = true; | |
2432 | } | |
2433 | } | |
2434 | else if (contains_type_p (outer_type, offset - ctx.offset, | |
2435 | ctx.outer_type, false, false)) | |
2436 | { | |
2437 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2438 | fprintf (dump_file, "First type contain the second as a field\n"); | |
2439 | ||
2440 | if (!dynamic | |
2441 | && (ctx.dynamic | |
2442 | || (!otr_type | |
2443 | && (!TYPE_SIZE (ctx.outer_type) | |
2444 | || !TYPE_SIZE (outer_type) | |
2445 | || !operand_equal_p (TYPE_SIZE (ctx.outer_type), | |
2446 | TYPE_SIZE (outer_type), 0))))) | |
2447 | dynamic = true; | |
2448 | outer_type = ctx.outer_type; | |
2449 | offset = ctx.offset; | |
2450 | dynamic = ctx.dynamic; | |
2451 | maybe_in_construction = ctx.maybe_in_construction; | |
2452 | maybe_derived_type = ctx.maybe_derived_type; | |
2453 | updated = true; | |
2454 | } | |
2455 | /* See if OUTER_TYPE is base of CTX.OUTER_TYPE. */ | |
2456 | else if (contains_type_p (ctx.outer_type, | |
2457 | ctx.offset - offset, outer_type, false, true)) | |
2458 | { | |
2459 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2460 | fprintf (dump_file, "First type is base of second\n"); | |
2461 | if (!maybe_derived_type) | |
2462 | { | |
2463 | maybe_derived_type = true; | |
2464 | updated = true; | |
2465 | } | |
2466 | if (!maybe_in_construction && ctx.maybe_in_construction) | |
2467 | { | |
2468 | maybe_in_construction = true; | |
2469 | updated = true; | |
2470 | } | |
2471 | if (!dynamic && ctx.dynamic) | |
2472 | { | |
2473 | dynamic = true; | |
2474 | updated = true; | |
2475 | } | |
2476 | } | |
2477 | /* See if CTX.OUTER_TYPE is base of OUTER_TYPE. */ | |
2478 | else if (contains_type_p (outer_type, | |
2479 | offset - ctx.offset, ctx.outer_type, false, true)) | |
2480 | { | |
2481 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2482 | fprintf (dump_file, "Second type is base of first\n"); | |
2483 | outer_type = ctx.outer_type; | |
2484 | offset = ctx.offset; | |
2485 | updated = true; | |
2486 | if (!maybe_derived_type) | |
2487 | maybe_derived_type = true; | |
2488 | if (!maybe_in_construction && ctx.maybe_in_construction) | |
2489 | maybe_in_construction = true; | |
2490 | if (!dynamic && ctx.dynamic) | |
2491 | dynamic = true; | |
2492 | } | |
2493 | /* TODO handle merging using hiearchy. */ | |
2494 | else | |
2495 | { | |
2496 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2497 | fprintf (dump_file, "Giving up on meet\n"); | |
2498 | clear_outer_type (); | |
2499 | updated = true; | |
2500 | } | |
2501 | ||
2502 | updated |= meet_speculation_with (ctx.speculative_outer_type, | |
2503 | ctx.speculative_offset, | |
2504 | ctx.speculative_maybe_derived_type, | |
2505 | otr_type); | |
2506 | ||
2507 | if (updated && dump_file && (dump_flags & TDF_DETAILS)) | |
2508 | { | |
2509 | fprintf (dump_file, "Updated as: "); | |
2510 | dump (dump_file); | |
2511 | fprintf (dump_file, "\n"); | |
2512 | } | |
2513 | return updated; | |
2514 | } |