Line data Source code
1 : /* Alias analysis for trees.
2 : Copyright (C) 2004-2026 Free Software Foundation, Inc.
3 : Contributed by Diego Novillo <dnovillo@redhat.com>
4 :
5 : This file is part of GCC.
6 :
7 : GCC is free software; you can redistribute it and/or modify
8 : it under the terms of the GNU General Public License as published by
9 : the Free Software Foundation; either version 3, or (at your option)
10 : any later version.
11 :
12 : GCC is distributed in the hope that it will be useful,
13 : but WITHOUT ANY WARRANTY; without even the implied warranty of
14 : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 : GNU General Public License 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 "backend.h"
25 : #include "target.h"
26 : #include "rtl.h"
27 : #include "tree.h"
28 : #include "gimple.h"
29 : #include "timevar.h" /* for TV_ALIAS_STMT_WALK */
30 : #include "ssa.h"
31 : #include "cgraph.h"
32 : #include "tree-pretty-print.h"
33 : #include "alias.h"
34 : #include "fold-const.h"
35 : #include "langhooks.h"
36 : #include "dumpfile.h"
37 : #include "tree-eh.h"
38 : #include "tree-dfa.h"
39 : #include "ipa-reference.h"
40 : #include "varasm.h"
41 : #include "ipa-modref-tree.h"
42 : #include "ipa-modref.h"
43 : #include "attr-fnspec.h"
44 : #include "errors.h"
45 : #include "dbgcnt.h"
46 : #include "gimple-pretty-print.h"
47 : #include "print-tree.h"
48 : #include "tree-ssa-alias-compare.h"
49 : #include "builtins.h"
50 : #include "internal-fn.h"
51 : #include "ipa-utils.h"
52 :
53 : /* Broad overview of how alias analysis on gimple works:
54 :
55 : Statements clobbering or using memory are linked through the
56 : virtual operand factored use-def chain. The virtual operand
57 : is unique per function, its symbol is accessible via gimple_vop (cfun).
58 : Virtual operands are used for efficiently walking memory statements
59 : in the gimple IL and are useful for things like value-numbering as
60 : a generation count for memory references.
61 :
62 : SSA_NAME pointers may have associated points-to information
63 : accessible via the SSA_NAME_PTR_INFO macro. Flow-insensitive
64 : points-to information is (re-)computed by the TODO_rebuild_alias
65 : pass manager todo. Points-to information is also used for more
66 : precise tracking of call-clobbered and call-used variables and
67 : related disambiguations.
68 :
69 : This file contains functions for disambiguating memory references,
70 : the so called alias-oracle and tools for walking of the gimple IL.
71 :
72 : The main alias-oracle entry-points are
73 :
74 : bool stmt_may_clobber_ref_p (gimple *, tree)
75 :
76 : This function queries if a statement may invalidate (parts of)
77 : the memory designated by the reference tree argument.
78 :
79 : bool ref_maybe_used_by_stmt_p (gimple *, tree)
80 :
81 : This function queries if a statement may need (parts of) the
82 : memory designated by the reference tree argument.
83 :
84 : There are variants of these functions that only handle the call
85 : part of a statement, call_may_clobber_ref_p and ref_maybe_used_by_call_p.
86 : Note that these do not disambiguate against a possible call lhs.
87 :
88 : bool refs_may_alias_p (tree, tree)
89 :
90 : This function tries to disambiguate two reference trees.
91 :
92 : bool ptr_deref_may_alias_global_p (tree, bool)
93 :
94 : This function queries if dereferencing a pointer variable may
95 : alias global memory. If bool argument is true, global memory
96 : is considered to also include function local memory that escaped.
97 :
98 : More low-level disambiguators are available and documented in
99 : this file. Low-level disambiguators dealing with points-to
100 : information are in tree-ssa-structalias.cc. */
101 :
102 : static int nonoverlapping_refs_since_match_p (tree, tree, tree, tree, bool);
103 : static bool nonoverlapping_component_refs_p (const_tree, const_tree);
104 :
105 : /* Query statistics for the different low-level disambiguators.
106 : A high-level query may trigger multiple of them. */
107 :
108 : static struct {
109 : unsigned HOST_WIDE_INT refs_may_alias_p_may_alias;
110 : unsigned HOST_WIDE_INT refs_may_alias_p_no_alias;
111 : unsigned HOST_WIDE_INT ref_maybe_used_by_call_p_may_alias;
112 : unsigned HOST_WIDE_INT ref_maybe_used_by_call_p_no_alias;
113 : unsigned HOST_WIDE_INT call_may_clobber_ref_p_may_alias;
114 : unsigned HOST_WIDE_INT call_may_clobber_ref_p_no_alias;
115 : unsigned HOST_WIDE_INT aliasing_component_refs_p_may_alias;
116 : unsigned HOST_WIDE_INT aliasing_component_refs_p_no_alias;
117 : unsigned HOST_WIDE_INT nonoverlapping_component_refs_p_may_alias;
118 : unsigned HOST_WIDE_INT nonoverlapping_component_refs_p_no_alias;
119 : unsigned HOST_WIDE_INT nonoverlapping_refs_since_match_p_may_alias;
120 : unsigned HOST_WIDE_INT nonoverlapping_refs_since_match_p_must_overlap;
121 : unsigned HOST_WIDE_INT nonoverlapping_refs_since_match_p_no_alias;
122 : unsigned HOST_WIDE_INT stmt_kills_ref_p_no;
123 : unsigned HOST_WIDE_INT stmt_kills_ref_p_yes;
124 : unsigned HOST_WIDE_INT modref_use_may_alias;
125 : unsigned HOST_WIDE_INT modref_use_no_alias;
126 : unsigned HOST_WIDE_INT modref_clobber_may_alias;
127 : unsigned HOST_WIDE_INT modref_clobber_no_alias;
128 : unsigned HOST_WIDE_INT modref_kill_no;
129 : unsigned HOST_WIDE_INT modref_kill_yes;
130 : unsigned HOST_WIDE_INT modref_tests;
131 : unsigned HOST_WIDE_INT modref_baseptr_tests;
132 : } alias_stats;
133 :
134 : void
135 0 : dump_alias_stats (FILE *s)
136 : {
137 0 : fprintf (s, "\nAlias oracle query stats:\n");
138 0 : fprintf (s, " refs_may_alias_p: "
139 : HOST_WIDE_INT_PRINT_DEC" disambiguations, "
140 : HOST_WIDE_INT_PRINT_DEC" queries\n",
141 : alias_stats.refs_may_alias_p_no_alias,
142 0 : alias_stats.refs_may_alias_p_no_alias
143 0 : + alias_stats.refs_may_alias_p_may_alias);
144 0 : fprintf (s, " ref_maybe_used_by_call_p: "
145 : HOST_WIDE_INT_PRINT_DEC" disambiguations, "
146 : HOST_WIDE_INT_PRINT_DEC" queries\n",
147 : alias_stats.ref_maybe_used_by_call_p_no_alias,
148 0 : alias_stats.refs_may_alias_p_no_alias
149 0 : + alias_stats.ref_maybe_used_by_call_p_may_alias);
150 0 : fprintf (s, " call_may_clobber_ref_p: "
151 : HOST_WIDE_INT_PRINT_DEC" disambiguations, "
152 : HOST_WIDE_INT_PRINT_DEC" queries\n",
153 : alias_stats.call_may_clobber_ref_p_no_alias,
154 0 : alias_stats.call_may_clobber_ref_p_no_alias
155 0 : + alias_stats.call_may_clobber_ref_p_may_alias);
156 0 : fprintf (s, " stmt_kills_ref_p: "
157 : HOST_WIDE_INT_PRINT_DEC" kills, "
158 : HOST_WIDE_INT_PRINT_DEC" queries\n",
159 : alias_stats.stmt_kills_ref_p_yes + alias_stats.modref_kill_yes,
160 0 : alias_stats.stmt_kills_ref_p_yes + alias_stats.modref_kill_yes
161 0 : + alias_stats.stmt_kills_ref_p_no + alias_stats.modref_kill_no);
162 0 : fprintf (s, " nonoverlapping_component_refs_p: "
163 : HOST_WIDE_INT_PRINT_DEC" disambiguations, "
164 : HOST_WIDE_INT_PRINT_DEC" queries\n",
165 : alias_stats.nonoverlapping_component_refs_p_no_alias,
166 0 : alias_stats.nonoverlapping_component_refs_p_no_alias
167 0 : + alias_stats.nonoverlapping_component_refs_p_may_alias);
168 0 : fprintf (s, " nonoverlapping_refs_since_match_p: "
169 : HOST_WIDE_INT_PRINT_DEC" disambiguations, "
170 : HOST_WIDE_INT_PRINT_DEC" must overlaps, "
171 : HOST_WIDE_INT_PRINT_DEC" queries\n",
172 : alias_stats.nonoverlapping_refs_since_match_p_no_alias,
173 : alias_stats.nonoverlapping_refs_since_match_p_must_overlap,
174 0 : alias_stats.nonoverlapping_refs_since_match_p_no_alias
175 0 : + alias_stats.nonoverlapping_refs_since_match_p_may_alias
176 0 : + alias_stats.nonoverlapping_refs_since_match_p_must_overlap);
177 0 : fprintf (s, " aliasing_component_refs_p: "
178 : HOST_WIDE_INT_PRINT_DEC" disambiguations, "
179 : HOST_WIDE_INT_PRINT_DEC" queries\n",
180 : alias_stats.aliasing_component_refs_p_no_alias,
181 0 : alias_stats.aliasing_component_refs_p_no_alias
182 0 : + alias_stats.aliasing_component_refs_p_may_alias);
183 0 : dump_alias_stats_in_alias_c (s);
184 0 : fprintf (s, "\nModref stats:\n");
185 0 : fprintf (s, " modref kill: "
186 : HOST_WIDE_INT_PRINT_DEC" kills, "
187 : HOST_WIDE_INT_PRINT_DEC" queries\n",
188 : alias_stats.modref_kill_yes,
189 0 : alias_stats.modref_kill_yes
190 0 : + alias_stats.modref_kill_no);
191 0 : fprintf (s, " modref use: "
192 : HOST_WIDE_INT_PRINT_DEC" disambiguations, "
193 : HOST_WIDE_INT_PRINT_DEC" queries\n",
194 : alias_stats.modref_use_no_alias,
195 0 : alias_stats.modref_use_no_alias
196 0 : + alias_stats.modref_use_may_alias);
197 0 : fprintf (s, " modref clobber: "
198 : HOST_WIDE_INT_PRINT_DEC" disambiguations, "
199 : HOST_WIDE_INT_PRINT_DEC" queries\n"
200 : " " HOST_WIDE_INT_PRINT_DEC" tbaa queries (%f per modref query)\n"
201 : " " HOST_WIDE_INT_PRINT_DEC" base compares (%f per modref query)\n",
202 : alias_stats.modref_clobber_no_alias,
203 : alias_stats.modref_clobber_no_alias
204 : + alias_stats.modref_clobber_may_alias,
205 : alias_stats.modref_tests,
206 0 : ((double)alias_stats.modref_tests)
207 : / (alias_stats.modref_clobber_no_alias
208 : + alias_stats.modref_clobber_may_alias),
209 : alias_stats.modref_baseptr_tests,
210 0 : ((double)alias_stats.modref_baseptr_tests)
211 0 : / (alias_stats.modref_clobber_no_alias
212 0 : + alias_stats.modref_clobber_may_alias));
213 0 : }
214 :
215 :
216 : /* Return true, if dereferencing PTR may alias with a global variable.
217 : When ESCAPED_LOCAL_P is true escaped local memory is also considered
218 : global. */
219 :
220 : bool
221 57794100 : ptr_deref_may_alias_global_p (tree ptr, bool escaped_local_p)
222 : {
223 57794100 : struct ptr_info_def *pi;
224 :
225 : /* If we end up with a pointer constant here that may point
226 : to global memory. */
227 57794100 : if (TREE_CODE (ptr) != SSA_NAME)
228 : return true;
229 :
230 57788051 : pi = SSA_NAME_PTR_INFO (ptr);
231 :
232 : /* If we do not have points-to information for this variable,
233 : we have to punt. */
234 57788051 : if (!pi)
235 : return true;
236 :
237 : /* ??? This does not use TBAA to prune globals ptr may not access. */
238 46135730 : return pt_solution_includes_global (&pi->pt, escaped_local_p);
239 : }
240 :
241 : /* Return true if dereferencing PTR may alias DECL.
242 : The caller is responsible for applying TBAA to see if PTR
243 : may access DECL at all. */
244 :
245 : static bool
246 210423868 : ptr_deref_may_alias_decl_p (tree ptr, tree decl)
247 : {
248 210423868 : struct ptr_info_def *pi;
249 :
250 : /* Conversions are irrelevant for points-to information and
251 : data-dependence analysis can feed us those. */
252 210423868 : STRIP_NOPS (ptr);
253 :
254 : /* Anything we do not explicilty handle aliases. */
255 210423868 : if ((TREE_CODE (ptr) != SSA_NAME
256 2347153 : && TREE_CODE (ptr) != ADDR_EXPR
257 1096056 : && TREE_CODE (ptr) != POINTER_PLUS_EXPR)
258 209327812 : || !POINTER_TYPE_P (TREE_TYPE (ptr))
259 419751296 : || (!VAR_P (decl)
260 : && TREE_CODE (decl) != PARM_DECL
261 : && TREE_CODE (decl) != RESULT_DECL))
262 : return true;
263 :
264 : /* Disregard pointer offsetting. */
265 209326371 : if (TREE_CODE (ptr) == POINTER_PLUS_EXPR)
266 : {
267 0 : do
268 : {
269 0 : ptr = TREE_OPERAND (ptr, 0);
270 : }
271 0 : while (TREE_CODE (ptr) == POINTER_PLUS_EXPR);
272 : return ptr_deref_may_alias_decl_p (ptr, decl);
273 : }
274 :
275 : /* ADDR_EXPR pointers either just offset another pointer or directly
276 : specify the pointed-to set. */
277 209326371 : if (TREE_CODE (ptr) == ADDR_EXPR)
278 : {
279 1250074 : tree base = get_base_address (TREE_OPERAND (ptr, 0));
280 1250074 : if (base
281 1250074 : && (TREE_CODE (base) == MEM_REF
282 1250074 : || TREE_CODE (base) == TARGET_MEM_REF))
283 18263 : ptr = TREE_OPERAND (base, 0);
284 1231811 : else if (base
285 1231811 : && DECL_P (base))
286 1214956 : return compare_base_decls (base, decl) != 0;
287 16855 : else if (base
288 16855 : && CONSTANT_CLASS_P (base))
289 : return false;
290 : else
291 : return true;
292 : }
293 :
294 : /* Non-aliased variables cannot be pointed to. */
295 208094560 : if (!may_be_aliased (decl))
296 : return false;
297 :
298 : /* From here we require a SSA name pointer. Anything else aliases. */
299 78761863 : if (TREE_CODE (ptr) != SSA_NAME
300 78761863 : || !POINTER_TYPE_P (TREE_TYPE (ptr)))
301 : return true;
302 :
303 : /* If we do not have useful points-to information for this pointer
304 : we cannot disambiguate anything else. */
305 78761863 : pi = SSA_NAME_PTR_INFO (ptr);
306 78761863 : if (!pi)
307 : return true;
308 :
309 77713517 : return pt_solution_includes (&pi->pt, decl);
310 : }
311 :
312 : /* Return true if dereferenced PTR1 and PTR2 may alias.
313 : The caller is responsible for applying TBAA to see if accesses
314 : through PTR1 and PTR2 may conflict at all. */
315 :
316 : bool
317 66315008 : ptr_derefs_may_alias_p (tree ptr1, tree ptr2)
318 : {
319 67686752 : struct ptr_info_def *pi1, *pi2;
320 :
321 : /* Conversions are irrelevant for points-to information and
322 : data-dependence analysis can feed us those. */
323 67686752 : STRIP_NOPS (ptr1);
324 67686752 : STRIP_NOPS (ptr2);
325 :
326 : /* Disregard pointer offsetting. */
327 67686752 : if (TREE_CODE (ptr1) == POINTER_PLUS_EXPR)
328 : {
329 569022 : do
330 : {
331 569022 : ptr1 = TREE_OPERAND (ptr1, 0);
332 : }
333 569022 : while (TREE_CODE (ptr1) == POINTER_PLUS_EXPR);
334 : return ptr_derefs_may_alias_p (ptr1, ptr2);
335 : }
336 67117730 : if (TREE_CODE (ptr2) == POINTER_PLUS_EXPR)
337 : {
338 582708 : do
339 : {
340 582708 : ptr2 = TREE_OPERAND (ptr2, 0);
341 : }
342 582708 : while (TREE_CODE (ptr2) == POINTER_PLUS_EXPR);
343 : return ptr_derefs_may_alias_p (ptr1, ptr2);
344 : }
345 :
346 : /* ADDR_EXPR pointers either just offset another pointer or directly
347 : specify the pointed-to set. */
348 66535022 : if (TREE_CODE (ptr1) == ADDR_EXPR)
349 : {
350 878780 : tree base = get_base_address (TREE_OPERAND (ptr1, 0));
351 878780 : if (base
352 878780 : && (TREE_CODE (base) == MEM_REF
353 878780 : || TREE_CODE (base) == TARGET_MEM_REF))
354 112499 : return ptr_derefs_may_alias_p (TREE_OPERAND (base, 0), ptr2);
355 766281 : else if (base
356 766281 : && DECL_P (base))
357 763600 : return ptr_deref_may_alias_decl_p (ptr2, base);
358 : /* Try ptr2 when ptr1 points to a constant. */
359 : else if (base
360 2681 : && !CONSTANT_CLASS_P (base))
361 : return true;
362 : }
363 65658923 : if (TREE_CODE (ptr2) == ADDR_EXPR)
364 : {
365 334623 : tree base = get_base_address (TREE_OPERAND (ptr2, 0));
366 334623 : if (base
367 334623 : && (TREE_CODE (base) == MEM_REF
368 334623 : || TREE_CODE (base) == TARGET_MEM_REF))
369 107515 : return ptr_derefs_may_alias_p (ptr1, TREE_OPERAND (base, 0));
370 227108 : else if (base
371 227108 : && DECL_P (base))
372 225044 : return ptr_deref_may_alias_decl_p (ptr1, base);
373 : else
374 : return true;
375 : }
376 :
377 : /* From here we require SSA name pointers. Anything else aliases. */
378 65324300 : if (TREE_CODE (ptr1) != SSA_NAME
379 65166917 : || TREE_CODE (ptr2) != SSA_NAME
380 65142622 : || !POINTER_TYPE_P (TREE_TYPE (ptr1))
381 130457112 : || !POINTER_TYPE_P (TREE_TYPE (ptr2)))
382 : return true;
383 :
384 : /* We may end up with two empty points-to solutions for two same pointers.
385 : In this case we still want to say both pointers alias, so shortcut
386 : that here. */
387 65132655 : if (ptr1 == ptr2)
388 : return true;
389 :
390 : /* If we do not have useful points-to information for either pointer
391 : we cannot disambiguate anything else. */
392 61327439 : pi1 = SSA_NAME_PTR_INFO (ptr1);
393 61327439 : pi2 = SSA_NAME_PTR_INFO (ptr2);
394 61327439 : if (!pi1 || !pi2)
395 : return true;
396 :
397 : /* ??? This does not use TBAA to prune decls from the intersection
398 : that not both pointers may access. */
399 58690425 : return pt_solutions_intersect (&pi1->pt, &pi2->pt);
400 : }
401 :
402 : /* Return true if dereferencing PTR may alias *REF.
403 : The caller is responsible for applying TBAA to see if PTR
404 : may access *REF at all. */
405 :
406 : static bool
407 1775402 : ptr_deref_may_alias_ref_p_1 (tree ptr, ao_ref *ref)
408 : {
409 1775402 : tree base = ao_ref_base (ref);
410 :
411 1775402 : if (TREE_CODE (base) == MEM_REF
412 1775402 : || TREE_CODE (base) == TARGET_MEM_REF)
413 171964 : return ptr_derefs_may_alias_p (ptr, TREE_OPERAND (base, 0));
414 1603438 : else if (DECL_P (base))
415 1601169 : return ptr_deref_may_alias_decl_p (ptr, base);
416 :
417 : return true;
418 : }
419 :
420 : /* Returns true if PTR1 and PTR2 compare unequal because of points-to. */
421 :
422 : bool
423 58285306 : ptrs_compare_unequal (tree ptr1, tree ptr2)
424 : {
425 : /* First resolve the pointers down to a SSA name pointer base or
426 : a VAR_DECL, PARM_DECL or RESULT_DECL. This explicitly does
427 : not yet try to handle LABEL_DECLs, FUNCTION_DECLs, CONST_DECLs
428 : or STRING_CSTs which needs points-to adjustments to track them
429 : in the points-to sets. */
430 58285306 : tree obj1 = NULL_TREE;
431 58285306 : tree obj2 = NULL_TREE;
432 58285306 : if (TREE_CODE (ptr1) == ADDR_EXPR)
433 : {
434 55130 : tree tem = get_base_address (TREE_OPERAND (ptr1, 0));
435 55130 : if (! tem)
436 : return false;
437 55130 : if (VAR_P (tem)
438 : || TREE_CODE (tem) == PARM_DECL
439 : || TREE_CODE (tem) == RESULT_DECL)
440 : obj1 = tem;
441 : else if (TREE_CODE (tem) == MEM_REF)
442 9096 : ptr1 = TREE_OPERAND (tem, 0);
443 : }
444 58285306 : if (TREE_CODE (ptr2) == ADDR_EXPR)
445 : {
446 9558502 : tree tem = get_base_address (TREE_OPERAND (ptr2, 0));
447 9558502 : if (! tem)
448 : return false;
449 9558502 : if (VAR_P (tem)
450 : || TREE_CODE (tem) == PARM_DECL
451 : || TREE_CODE (tem) == RESULT_DECL)
452 : obj2 = tem;
453 : else if (TREE_CODE (tem) == MEM_REF)
454 160661 : ptr2 = TREE_OPERAND (tem, 0);
455 : }
456 :
457 : /* Canonicalize ptr vs. object. */
458 58285306 : if (TREE_CODE (ptr1) == SSA_NAME && obj2)
459 : {
460 : std::swap (ptr1, ptr2);
461 : std::swap (obj1, obj2);
462 : }
463 :
464 58285306 : if (obj1 && obj2)
465 : /* Other code handles this correctly, no need to duplicate it here. */;
466 6131176 : else if (obj1 && TREE_CODE (ptr2) == SSA_NAME)
467 : {
468 6119893 : struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr2);
469 : /* We may not use restrict to optimize pointer comparisons.
470 : See PR71062. So we have to assume that restrict-pointed-to
471 : may be in fact obj1. */
472 6119893 : if (!pi
473 5024054 : || pi->pt.vars_contains_restrict
474 5010752 : || pi->pt.vars_contains_interposable)
475 : return false;
476 4290501 : if (VAR_P (obj1)
477 4290501 : && (TREE_STATIC (obj1) || DECL_EXTERNAL (obj1)))
478 : {
479 1125201 : varpool_node *node = varpool_node::get (obj1);
480 : /* If obj1 may bind to NULL give up (see below). */
481 1125201 : if (! node
482 1125201 : || ! node->nonzero_address ()
483 2250402 : || ! decl_binds_to_current_def_p (obj1))
484 849182 : return false;
485 : }
486 3441319 : return !pt_solution_includes (&pi->pt, obj1);
487 : }
488 52153350 : else if (TREE_CODE (ptr1) == SSA_NAME)
489 : {
490 44972294 : struct ptr_info_def *pi1 = SSA_NAME_PTR_INFO (ptr1);
491 44972294 : if (!pi1
492 34359514 : || pi1->pt.vars_contains_restrict
493 33315597 : || pi1->pt.vars_contains_interposable)
494 : return false;
495 31395121 : if (integer_zerop (ptr2) && !pi1->pt.null)
496 : return true;
497 31372797 : if (TREE_CODE (ptr2) == SSA_NAME)
498 : {
499 10717326 : struct ptr_info_def *pi2 = SSA_NAME_PTR_INFO (ptr2);
500 10717326 : if (!pi2
501 10109978 : || pi2->pt.vars_contains_restrict
502 10103654 : || pi2->pt.vars_contains_interposable)
503 : return false;
504 8335608 : if ((!pi1->pt.null || !pi2->pt.null)
505 : /* ??? We do not represent FUNCTION_DECL and LABEL_DECL
506 : in pt.vars but only set pt.vars_contains_nonlocal. This
507 : makes compares involving those and other nonlocals
508 : imprecise. */
509 4238976 : && (!pi1->pt.vars_contains_nonlocal
510 62923 : || !pi2->pt.vars_contains_nonlocal)
511 14216225 : && (!pt_solution_includes_const_pool (&pi1->pt)
512 3799650 : || !pt_solution_includes_const_pool (&pi2->pt)))
513 485677 : return !pt_solutions_intersect (&pi1->pt, &pi2->pt);
514 : }
515 : }
516 :
517 : return false;
518 : }
519 :
520 : /* Returns whether reference REF to BASE may refer to global memory.
521 : When ESCAPED_LOCAL_P is true escaped local memory is also considered
522 : global. */
523 :
524 : static bool
525 54800260 : ref_may_alias_global_p_1 (tree base, bool escaped_local_p)
526 : {
527 54800260 : if (DECL_P (base))
528 42702857 : return (is_global_var (base)
529 42702857 : || (escaped_local_p
530 1339934 : && pt_solution_includes (&cfun->gimple_df->escaped_return,
531 : base)));
532 12097403 : else if (TREE_CODE (base) == MEM_REF
533 12097403 : || TREE_CODE (base) == TARGET_MEM_REF)
534 12087379 : return ptr_deref_may_alias_global_p (TREE_OPERAND (base, 0),
535 12087379 : escaped_local_p);
536 : return true;
537 : }
538 :
539 : bool
540 11205065 : ref_may_alias_global_p (ao_ref *ref, bool escaped_local_p)
541 : {
542 11205065 : tree base = ao_ref_base (ref);
543 11205065 : return ref_may_alias_global_p_1 (base, escaped_local_p);
544 : }
545 :
546 : bool
547 43595195 : ref_may_alias_global_p (tree ref, bool escaped_local_p)
548 : {
549 43595195 : tree base = get_base_address (ref);
550 43595195 : return ref_may_alias_global_p_1 (base, escaped_local_p);
551 : }
552 :
553 : /* Return true whether STMT may clobber global memory.
554 : When ESCAPED_LOCAL_P is true escaped local memory is also considered
555 : global. */
556 :
557 : bool
558 178196164 : stmt_may_clobber_global_p (gimple *stmt, bool escaped_local_p)
559 : {
560 178196164 : tree lhs;
561 :
562 355098529 : if (!gimple_vdef (stmt))
563 : return false;
564 :
565 : /* ??? We can ask the oracle whether an artificial pointer
566 : dereference with a pointer with points-to information covering
567 : all global memory (what about non-address taken memory?) maybe
568 : clobbered by this call. As there is at the moment no convenient
569 : way of doing that without generating garbage do some manual
570 : checking instead.
571 : ??? We could make a NULL ao_ref argument to the various
572 : predicates special, meaning any global memory. */
573 :
574 43773644 : switch (gimple_code (stmt))
575 : {
576 43595195 : case GIMPLE_ASSIGN:
577 43595195 : lhs = gimple_assign_lhs (stmt);
578 43595195 : return (TREE_CODE (lhs) != SSA_NAME
579 43595195 : && ref_may_alias_global_p (lhs, escaped_local_p));
580 : case GIMPLE_CALL:
581 : return true;
582 : default:
583 : return true;
584 : }
585 : }
586 :
587 :
588 : /* Dump alias information on FILE. */
589 :
590 : void
591 286 : dump_alias_info (FILE *file)
592 : {
593 286 : unsigned i;
594 286 : tree ptr;
595 286 : const char *funcname
596 286 : = lang_hooks.decl_printable_name (current_function_decl, 2);
597 286 : tree var;
598 :
599 286 : fprintf (file, "\n\nAlias information for %s\n\n", funcname);
600 :
601 286 : fprintf (file, "Aliased symbols\n\n");
602 :
603 1149 : FOR_EACH_LOCAL_DECL (cfun, i, var)
604 : {
605 606 : if (may_be_aliased (var))
606 357 : dump_variable (file, var);
607 : }
608 :
609 286 : fprintf (file, "\nCall clobber information\n");
610 :
611 286 : fprintf (file, "\nESCAPED");
612 286 : dump_points_to_solution (file, &cfun->gimple_df->escaped);
613 :
614 286 : fprintf (file, "\nESCAPED_RETURN");
615 286 : dump_points_to_solution (file, &cfun->gimple_df->escaped_return);
616 :
617 286 : fprintf (file, "\n\nFlow-insensitive points-to information\n\n");
618 :
619 3088 : FOR_EACH_SSA_NAME (i, ptr, cfun)
620 : {
621 2570 : struct ptr_info_def *pi;
622 :
623 4693 : if (!POINTER_TYPE_P (TREE_TYPE (ptr))
624 2617 : || SSA_NAME_IN_FREE_LIST (ptr))
625 2076 : continue;
626 :
627 494 : pi = SSA_NAME_PTR_INFO (ptr);
628 494 : if (pi)
629 487 : dump_points_to_info_for (file, ptr);
630 : }
631 :
632 286 : fprintf (file, "\n");
633 286 : }
634 :
635 :
636 : /* Dump alias information on stderr. */
637 :
638 : DEBUG_FUNCTION void
639 0 : debug_alias_info (void)
640 : {
641 0 : dump_alias_info (stderr);
642 0 : }
643 :
644 :
645 : /* Dump the points-to set *PT into FILE. */
646 :
647 : void
648 1059 : dump_points_to_solution (FILE *file, struct pt_solution *pt)
649 : {
650 1059 : if (pt->anything)
651 3 : fprintf (file, ", points-to anything");
652 :
653 1059 : if (pt->nonlocal)
654 635 : fprintf (file, ", points-to non-local");
655 :
656 1059 : if (pt->escaped)
657 423 : fprintf (file, ", points-to escaped");
658 :
659 1059 : if (pt->ipa_escaped)
660 0 : fprintf (file, ", points-to unit escaped");
661 :
662 1059 : if (pt->null)
663 614 : fprintf (file, ", points-to NULL");
664 :
665 1059 : if (pt->const_pool)
666 0 : fprintf (file, ", points-to const-pool");
667 :
668 1059 : if (pt->vars)
669 : {
670 1056 : fprintf (file, ", points-to vars: ");
671 1056 : dump_decl_set (file, pt->vars);
672 1056 : if (pt->vars_contains_nonlocal
673 921 : || pt->vars_contains_escaped
674 844 : || pt->vars_contains_escaped_heap
675 844 : || pt->vars_contains_restrict
676 844 : || pt->vars_contains_interposable)
677 : {
678 212 : const char *comma = "";
679 212 : fprintf (file, " (");
680 212 : if (pt->vars_contains_nonlocal)
681 : {
682 135 : fprintf (file, "nonlocal");
683 135 : comma = ", ";
684 : }
685 212 : if (pt->vars_contains_escaped)
686 : {
687 139 : fprintf (file, "%sescaped", comma);
688 139 : comma = ", ";
689 : }
690 212 : if (pt->vars_contains_escaped_heap)
691 : {
692 0 : fprintf (file, "%sescaped heap", comma);
693 0 : comma = ", ";
694 : }
695 212 : if (pt->vars_contains_restrict)
696 : {
697 58 : fprintf (file, "%srestrict", comma);
698 58 : comma = ", ";
699 : }
700 212 : if (pt->vars_contains_interposable)
701 0 : fprintf (file, "%sinterposable", comma);
702 212 : fprintf (file, ")");
703 : }
704 : }
705 1059 : }
706 :
707 :
708 : /* Unified dump function for pt_solution. */
709 :
710 : DEBUG_FUNCTION void
711 0 : debug (pt_solution &ref)
712 : {
713 0 : dump_points_to_solution (stderr, &ref);
714 0 : }
715 :
716 : DEBUG_FUNCTION void
717 0 : debug (pt_solution *ptr)
718 : {
719 0 : if (ptr)
720 0 : debug (*ptr);
721 : else
722 0 : fprintf (stderr, "<nil>\n");
723 0 : }
724 :
725 :
726 : /* Dump points-to information for SSA_NAME PTR into FILE. */
727 :
728 : void
729 487 : dump_points_to_info_for (FILE *file, tree ptr)
730 : {
731 487 : struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr);
732 :
733 487 : print_generic_expr (file, ptr, dump_flags);
734 :
735 487 : if (pi)
736 487 : dump_points_to_solution (file, &pi->pt);
737 : else
738 0 : fprintf (file, ", points-to anything");
739 :
740 487 : fprintf (file, "\n");
741 487 : }
742 :
743 :
744 : /* Dump points-to information for VAR into stderr. */
745 :
746 : DEBUG_FUNCTION void
747 0 : debug_points_to_info_for (tree var)
748 : {
749 0 : dump_points_to_info_for (stderr, var);
750 0 : }
751 :
752 :
753 : /* Initializes the alias-oracle reference representation *R from REF. */
754 :
755 : void
756 2749757137 : ao_ref_init (ao_ref *r, tree ref)
757 : {
758 2749757137 : r->ref = ref;
759 2749757137 : r->base = NULL_TREE;
760 2749757137 : r->offset = 0;
761 2749757137 : r->size = -1;
762 2749757137 : r->max_size = -1;
763 2749757137 : r->ref_alias_set = -1;
764 2749757137 : r->base_alias_set = -1;
765 2749757137 : r->volatile_p = ref ? TREE_THIS_VOLATILE (ref) : false;
766 2749757137 : }
767 :
768 : /* Returns the base object of the memory reference *REF. */
769 :
770 : tree
771 5355545717 : ao_ref_base (ao_ref *ref)
772 : {
773 5355545717 : bool reverse;
774 :
775 5355545717 : if (ref->base)
776 : return ref->base;
777 2484087792 : ref->base = get_ref_base_and_extent (ref->ref, &ref->offset, &ref->size,
778 : &ref->max_size, &reverse);
779 2484087792 : return ref->base;
780 : }
781 :
782 : /* Returns the base object alias set of the memory reference *REF. */
783 :
784 : alias_set_type
785 999792581 : ao_ref_base_alias_set (ao_ref *ref)
786 : {
787 999792581 : tree base_ref;
788 999792581 : if (ref->base_alias_set != -1)
789 : return ref->base_alias_set;
790 776458991 : if (!ref->ref)
791 : return 0;
792 739318791 : base_ref = ref->ref;
793 739318791 : if (TREE_CODE (base_ref) == WITH_SIZE_EXPR)
794 4 : base_ref = TREE_OPERAND (base_ref, 0);
795 1185750470 : while (handled_component_p (base_ref))
796 446431679 : base_ref = TREE_OPERAND (base_ref, 0);
797 739318791 : ref->base_alias_set = get_alias_set (base_ref);
798 739318791 : return ref->base_alias_set;
799 : }
800 :
801 : /* Returns the reference alias set of the memory reference *REF. */
802 :
803 : alias_set_type
804 1258949921 : ao_ref_alias_set (ao_ref *ref)
805 : {
806 1258949921 : if (ref->ref_alias_set != -1)
807 : return ref->ref_alias_set;
808 507617167 : if (!ref->ref)
809 : return 0;
810 507617165 : ref->ref_alias_set = get_alias_set (ref->ref);
811 507617165 : return ref->ref_alias_set;
812 : }
813 :
814 : /* Returns a type satisfying
815 : get_deref_alias_set (type) == ao_ref_base_alias_set (REF). */
816 :
817 : tree
818 323645 : ao_ref_base_alias_ptr_type (ao_ref *ref)
819 : {
820 323645 : tree base_ref;
821 :
822 323645 : if (!ref->ref)
823 : return NULL_TREE;
824 323645 : base_ref = ref->ref;
825 323645 : if (TREE_CODE (base_ref) == WITH_SIZE_EXPR)
826 0 : base_ref = TREE_OPERAND (base_ref, 0);
827 431938 : while (handled_component_p (base_ref))
828 108293 : base_ref = TREE_OPERAND (base_ref, 0);
829 323645 : tree ret = reference_alias_ptr_type (base_ref);
830 323645 : return ret;
831 : }
832 :
833 : /* Returns a type satisfying
834 : get_deref_alias_set (type) == ao_ref_alias_set (REF). */
835 :
836 : tree
837 323645 : ao_ref_alias_ptr_type (ao_ref *ref)
838 : {
839 323645 : if (!ref->ref)
840 : return NULL_TREE;
841 323645 : tree ret = reference_alias_ptr_type (ref->ref);
842 323645 : return ret;
843 : }
844 :
845 : /* Return the alignment of the access *REF and store it in the *ALIGN
846 : and *BITPOS pairs. Returns false if no alignment could be determined.
847 : See get_object_alignment_2 for details. */
848 :
849 : bool
850 94326 : ao_ref_alignment (ao_ref *ref, unsigned int *align,
851 : unsigned HOST_WIDE_INT *bitpos)
852 : {
853 94326 : if (ref->ref)
854 92778 : return get_object_alignment_1 (ref->ref, align, bitpos);
855 :
856 : /* When we just have ref->base we cannot use get_object_alignment since
857 : that will eventually use the type of the appearant access while for
858 : example ao_ref_init_from_ptr_and_range is not careful to adjust that. */
859 1548 : *align = BITS_PER_UNIT;
860 1548 : HOST_WIDE_INT offset;
861 1548 : if (!ref->offset.is_constant (&offset)
862 1548 : || !get_object_alignment_2 (ref->base, align, bitpos, true))
863 : return false;
864 1328 : *bitpos += (unsigned HOST_WIDE_INT)offset * BITS_PER_UNIT;
865 1328 : *bitpos = *bitpos & (*align - 1);
866 1328 : return true;
867 : }
868 :
869 : /* Init an alias-oracle reference representation from a gimple pointer
870 : PTR a range specified by OFFSET, SIZE and MAX_SIZE under the assumption
871 : that RANGE_KNOWN is set.
872 :
873 : The access is assumed to be only to or after of the pointer target adjusted
874 : by the offset, not before it (even in the case RANGE_KNOWN is false). */
875 :
876 : void
877 40166691 : ao_ref_init_from_ptr_and_range (ao_ref *ref, tree ptr,
878 : bool range_known,
879 : poly_int64 offset,
880 : poly_int64 size,
881 : poly_int64 max_size)
882 : {
883 40166691 : poly_int64 t, extra_offset = 0;
884 :
885 40166691 : ref->ref = NULL_TREE;
886 40166691 : if (TREE_CODE (ptr) == SSA_NAME)
887 : {
888 26113097 : gimple *stmt = SSA_NAME_DEF_STMT (ptr);
889 26113097 : if (gimple_assign_single_p (stmt)
890 26113097 : && gimple_assign_rhs_code (stmt) == ADDR_EXPR)
891 4057720 : ptr = gimple_assign_rhs1 (stmt);
892 22055377 : else if (is_gimple_assign (stmt)
893 14756337 : && gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR
894 27873386 : && ptrdiff_tree_p (gimple_assign_rhs2 (stmt), &extra_offset))
895 : {
896 300651 : ptr = gimple_assign_rhs1 (stmt);
897 300651 : extra_offset *= BITS_PER_UNIT;
898 : }
899 : }
900 :
901 40166691 : if (TREE_CODE (ptr) == ADDR_EXPR)
902 : {
903 18043235 : ref->base = get_addr_base_and_unit_offset (TREE_OPERAND (ptr, 0), &t);
904 18043235 : if (ref->base
905 33250267 : && coeffs_in_range_p (t, -HOST_WIDE_INT_MAX / BITS_PER_UNIT,
906 : HOST_WIDE_INT_MAX / BITS_PER_UNIT))
907 15206854 : ref->offset = BITS_PER_UNIT * t;
908 : else
909 : {
910 2836381 : range_known = false;
911 2836381 : ref->offset = 0;
912 2836381 : ref->base = get_base_address (TREE_OPERAND (ptr, 0));
913 : }
914 : }
915 : else
916 : {
917 22123456 : gcc_assert (POINTER_TYPE_P (TREE_TYPE (ptr)));
918 22123456 : ref->base = build2 (MEM_REF, char_type_node,
919 : ptr, null_pointer_node);
920 22123456 : ref->offset = 0;
921 : }
922 40166691 : ref->offset += extra_offset + offset;
923 40166691 : if (range_known)
924 : {
925 21571447 : ref->max_size = max_size;
926 21571447 : ref->size = size;
927 : }
928 : else
929 18595244 : ref->max_size = ref->size = -1;
930 40166691 : ref->ref_alias_set = 0;
931 40166691 : ref->base_alias_set = 0;
932 40166691 : ref->volatile_p = false;
933 40166691 : }
934 :
935 : /* Init an alias-oracle reference representation from a gimple pointer
936 : PTR and a gimple size SIZE in bytes. If SIZE is NULL_TREE then the
937 : size is assumed to be unknown. The access is assumed to be only
938 : to or after of the pointer target, not before it. */
939 :
940 : void
941 10727231 : ao_ref_init_from_ptr_and_size (ao_ref *ref, tree ptr, tree size)
942 : {
943 10727231 : poly_int64 size_hwi;
944 10727231 : if (size
945 5533434 : && poly_int_tree_p (size, &size_hwi)
946 15593928 : && coeffs_in_range_p (size_hwi, 0, HOST_WIDE_INT_MAX / BITS_PER_UNIT))
947 : {
948 4865988 : size_hwi = size_hwi * BITS_PER_UNIT;
949 4865988 : ao_ref_init_from_ptr_and_range (ref, ptr, true, 0, size_hwi, size_hwi);
950 : }
951 : else
952 5861243 : ao_ref_init_from_ptr_and_range (ref, ptr, false, 0, -1, -1);
953 10727231 : }
954 :
955 : /* S1 and S2 are TYPE_SIZE or DECL_SIZE. Compare them:
956 : Return -1 if S1 < S2
957 : Return 1 if S1 > S2
958 : Return 0 if equal or incomparable. */
959 :
960 : static int
961 8653108 : compare_sizes (tree s1, tree s2)
962 : {
963 8653108 : if (!s1 || !s2)
964 : return 0;
965 :
966 8643717 : poly_uint64 size1;
967 8643717 : poly_uint64 size2;
968 :
969 8643717 : if (!poly_int_tree_p (s1, &size1) || !poly_int_tree_p (s2, &size2))
970 498 : return 0;
971 8643219 : if (known_lt (size1, size2))
972 : return -1;
973 6173705 : if (known_lt (size2, size1))
974 : return 1;
975 : return 0;
976 : }
977 :
978 : /* Compare TYPE1 and TYPE2 by its size.
979 : Return -1 if size of TYPE1 < size of TYPE2
980 : Return 1 if size of TYPE1 > size of TYPE2
981 : Return 0 if types are of equal sizes or we can not compare them. */
982 :
983 : static int
984 7339154 : compare_type_sizes (tree type1, tree type2)
985 : {
986 : /* Be conservative for arrays and vectors. We want to support partial
987 : overlap on int[3] and int[3] as tested in gcc.dg/torture/alias-2.c. */
988 7339154 : while (TREE_CODE (type1) == ARRAY_TYPE
989 8079313 : || VECTOR_TYPE_P (type1))
990 740159 : type1 = TREE_TYPE (type1);
991 7533567 : while (TREE_CODE (type2) == ARRAY_TYPE
992 7533567 : || VECTOR_TYPE_P (type2))
993 194413 : type2 = TREE_TYPE (type2);
994 7339154 : return compare_sizes (TYPE_SIZE (type1), TYPE_SIZE (type2));
995 : }
996 :
997 : /* Return 1 if TYPE1 and TYPE2 are to be considered equivalent for the
998 : purpose of TBAA. Return 0 if they are distinct and -1 if we cannot
999 : decide. */
1000 :
1001 : static inline int
1002 842839234 : same_type_for_tbaa (tree type1, tree type2)
1003 : {
1004 842839234 : type1 = TYPE_MAIN_VARIANT (type1);
1005 842839234 : type2 = TYPE_MAIN_VARIANT (type2);
1006 :
1007 : /* Handle the most common case first. */
1008 842839234 : if (type1 == type2)
1009 : return 1;
1010 :
1011 : /* If we would have to do structural comparison bail out. */
1012 131947364 : if (TYPE_STRUCTURAL_EQUALITY_P (type1)
1013 131947364 : || TYPE_STRUCTURAL_EQUALITY_P (type2))
1014 : return -1;
1015 :
1016 : /* Compare the canonical types. */
1017 79488129 : if (TYPE_CANONICAL (type1) == TYPE_CANONICAL (type2))
1018 : return 1;
1019 :
1020 : /* ??? Array types are not properly unified in all cases as we have
1021 : spurious changes in the index types for example. Removing this
1022 : causes all sorts of problems with the Fortran frontend. */
1023 78661188 : if (TREE_CODE (type1) == ARRAY_TYPE
1024 4805254 : && TREE_CODE (type2) == ARRAY_TYPE)
1025 : return -1;
1026 :
1027 : /* ??? In Ada, an lvalue of an unconstrained type can be used to access an
1028 : object of one of its constrained subtypes, e.g. when a function with an
1029 : unconstrained parameter passed by reference is called on an object and
1030 : inlined. But, even in the case of a fixed size, type and subtypes are
1031 : not equivalent enough as to share the same TYPE_CANONICAL, since this
1032 : would mean that conversions between them are useless, whereas they are
1033 : not (e.g. type and subtypes can have different modes). So, in the end,
1034 : they are only guaranteed to have the same alias set. */
1035 78343903 : alias_set_type set1 = get_alias_set (type1);
1036 78343903 : alias_set_type set2 = get_alias_set (type2);
1037 78343903 : if (set1 == set2)
1038 : return -1;
1039 :
1040 : /* Pointers to void are considered compatible with all other pointers,
1041 : so for two pointers see what the alias set resolution thinks. */
1042 42523497 : if (POINTER_TYPE_P (type1)
1043 10066621 : && POINTER_TYPE_P (type2)
1044 42699864 : && alias_sets_conflict_p (set1, set2))
1045 : return -1;
1046 :
1047 : /* The types are known to be not equal. */
1048 : return 0;
1049 : }
1050 :
1051 : /* Return true if TYPE is a composite type (i.e. we may apply one of handled
1052 : components on it). */
1053 :
1054 : static bool
1055 1905569 : type_has_components_p (tree type)
1056 : {
1057 1905569 : return AGGREGATE_TYPE_P (type) || VECTOR_TYPE_P (type)
1058 1905569 : || TREE_CODE (type) == COMPLEX_TYPE;
1059 : }
1060 :
1061 : /* MATCH1 and MATCH2 which are part of access path of REF1 and REF2
1062 : respectively are either pointing to same address or are completely
1063 : disjoint. If PARTIAL_OVERLAP is true, assume that outermost arrays may
1064 : just partly overlap.
1065 :
1066 : Try to disambiguate using the access path starting from the match
1067 : and return false if there is no conflict.
1068 :
1069 : Helper for aliasing_component_refs_p. */
1070 :
1071 : static bool
1072 872402 : aliasing_matching_component_refs_p (tree match1, tree ref1,
1073 : poly_int64 offset1, poly_int64 max_size1,
1074 : tree match2, tree ref2,
1075 : poly_int64 offset2, poly_int64 max_size2,
1076 : bool partial_overlap)
1077 : {
1078 872402 : poly_int64 offadj, sztmp, msztmp;
1079 872402 : bool reverse;
1080 :
1081 872402 : if (!partial_overlap)
1082 : {
1083 872394 : get_ref_base_and_extent (match2, &offadj, &sztmp, &msztmp, &reverse);
1084 872394 : offset2 -= offadj;
1085 872394 : get_ref_base_and_extent (match1, &offadj, &sztmp, &msztmp, &reverse);
1086 872394 : offset1 -= offadj;
1087 872394 : if (!ranges_maybe_overlap_p (offset1, max_size1, offset2, max_size2))
1088 : {
1089 65996 : ++alias_stats.aliasing_component_refs_p_no_alias;
1090 65996 : return false;
1091 : }
1092 : }
1093 :
1094 806406 : int cmp = nonoverlapping_refs_since_match_p (match1, ref1, match2, ref2,
1095 : partial_overlap);
1096 806406 : if (cmp == 1
1097 806406 : || (cmp == -1 && nonoverlapping_component_refs_p (ref1, ref2)))
1098 : {
1099 326 : ++alias_stats.aliasing_component_refs_p_no_alias;
1100 326 : return false;
1101 : }
1102 806080 : ++alias_stats.aliasing_component_refs_p_may_alias;
1103 806080 : return true;
1104 : }
1105 :
1106 : /* Return true if REF is reference to zero sized trailing array. I.e.
1107 : struct foo {int bar; int array[0];} *fooptr;
1108 : fooptr->array. */
1109 :
1110 : static bool
1111 6195533 : component_ref_to_zero_sized_trailing_array_p (tree ref)
1112 : {
1113 6195533 : return (TREE_CODE (ref) == COMPONENT_REF
1114 5603314 : && TREE_CODE (TREE_TYPE (TREE_OPERAND (ref, 1))) == ARRAY_TYPE
1115 128574 : && (!TYPE_SIZE (TREE_TYPE (TREE_OPERAND (ref, 1)))
1116 42257 : || integer_zerop (TYPE_SIZE (TREE_TYPE (TREE_OPERAND (ref, 1)))))
1117 6281927 : && array_ref_flexible_size_p (ref));
1118 : }
1119 :
1120 : /* Worker for aliasing_component_refs_p. Most parameters match parameters of
1121 : aliasing_component_refs_p.
1122 :
1123 : Walk access path REF2 and try to find type matching TYPE1
1124 : (which is a start of possibly aliasing access path REF1).
1125 : If match is found, try to disambiguate.
1126 :
1127 : Return 0 for sucessful disambiguation.
1128 : Return 1 if match was found but disambiguation failed
1129 : Return -1 if there is no match.
1130 : In this case MAYBE_MATCH is set to 0 if there is no type matching TYPE1
1131 : in access patch REF2 and -1 if we are not sure. */
1132 :
1133 : static int
1134 2517227 : aliasing_component_refs_walk (tree ref1, tree type1, tree base1,
1135 : poly_int64 offset1, poly_int64 max_size1,
1136 : tree end_struct_ref1,
1137 : tree ref2, tree base2,
1138 : poly_int64 offset2, poly_int64 max_size2,
1139 : bool *maybe_match)
1140 : {
1141 2517227 : tree ref = ref2;
1142 2517227 : int same_p = 0;
1143 :
1144 7246191 : while (true)
1145 : {
1146 : /* We walk from inner type to the outer types. If type we see is
1147 : already too large to be part of type1, terminate the search. */
1148 4881709 : int cmp = compare_type_sizes (type1, TREE_TYPE (ref));
1149 :
1150 4881709 : if (cmp < 0
1151 4881709 : && (!end_struct_ref1
1152 60 : || compare_type_sizes (TREE_TYPE (end_struct_ref1),
1153 60 : TREE_TYPE (ref)) < 0))
1154 : break;
1155 : /* If types may be of same size, see if we can decide about their
1156 : equality. */
1157 3562255 : if (cmp == 0)
1158 : {
1159 2570413 : same_p = same_type_for_tbaa (TREE_TYPE (ref), type1);
1160 2570413 : if (same_p == 1)
1161 : break;
1162 : /* In case we can't decide whether types are same try to
1163 : continue looking for the exact match.
1164 : Remember however that we possibly saw a match
1165 : to bypass the access path continuations tests we do later. */
1166 1698011 : if (same_p == -1)
1167 624168 : *maybe_match = true;
1168 : }
1169 2689853 : if (!handled_component_p (ref))
1170 : break;
1171 2364482 : ref = TREE_OPERAND (ref, 0);
1172 2364482 : }
1173 2517227 : if (same_p == 1)
1174 : {
1175 872402 : bool partial_overlap = false;
1176 :
1177 : /* We assume that arrays can overlap by multiple of their elements
1178 : size as tested in gcc.dg/torture/alias-2.c.
1179 : This partial overlap happen only when both arrays are bases of
1180 : the access and not contained within another component ref.
1181 : To be safe we also assume partial overlap for VLAs. */
1182 872402 : if (TREE_CODE (TREE_TYPE (base1)) == ARRAY_TYPE
1183 872402 : && (!TYPE_SIZE (TREE_TYPE (base1))
1184 2087 : || TREE_CODE (TYPE_SIZE (TREE_TYPE (base1))) != INTEGER_CST
1185 2087 : || ref == base2))
1186 : {
1187 : /* Setting maybe_match to true triggers
1188 : nonoverlapping_component_refs_p test later that still may do
1189 : useful disambiguation. */
1190 8 : *maybe_match = true;
1191 8 : partial_overlap = true;
1192 : }
1193 872402 : return aliasing_matching_component_refs_p (base1, ref1,
1194 : offset1, max_size1,
1195 : ref, ref2,
1196 : offset2, max_size2,
1197 872402 : partial_overlap);
1198 : }
1199 : return -1;
1200 : }
1201 :
1202 : /* Consider access path1 base1....ref1 and access path2 base2...ref2.
1203 : Return true if they can be composed to single access path
1204 : base1...ref1...base2...ref2.
1205 :
1206 : REF_TYPE1 if type of REF1. END_STRUCT_PAST_END1 is true if there is
1207 : a trailing array access after REF1 in the non-TBAA part of the access.
1208 : REF1_ALIAS_SET is the alias set of REF1.
1209 :
1210 : BASE_TYPE2 is type of base2. END_STRUCT_REF2 is non-NULL if there is
1211 : a trailing array access in the TBAA part of access path2.
1212 : BASE2_ALIAS_SET is the alias set of base2. */
1213 :
1214 : bool
1215 1905569 : access_path_may_continue_p (tree ref_type1, bool end_struct_past_end1,
1216 : alias_set_type ref1_alias_set,
1217 : tree base_type2, tree end_struct_ref2,
1218 : alias_set_type base2_alias_set)
1219 : {
1220 : /* Access path can not continue past types with no components. */
1221 1905569 : if (!type_has_components_p (ref_type1))
1222 : return false;
1223 :
1224 : /* If first access path ends by too small type to hold base of
1225 : the second access path, typically paths can not continue.
1226 :
1227 : Punt if end_struct_past_end1 is true. We want to support arbitrary
1228 : type puning past first COMPONENT_REF to union because redundant store
1229 : elimination depends on this, see PR92152. For this reason we can not
1230 : check size of the reference because types may partially overlap. */
1231 156260 : if (!end_struct_past_end1)
1232 : {
1233 156211 : if (compare_type_sizes (ref_type1, base_type2) < 0)
1234 : return false;
1235 : /* If the path2 contains trailing array access we can strenghten the check
1236 : to verify that also the size of element of the trailing array fits.
1237 : In fact we could check for offset + type_size, but we do not track
1238 : offsets and this is quite side case. */
1239 142487 : if (end_struct_ref2
1240 142487 : && compare_type_sizes (ref_type1, TREE_TYPE (end_struct_ref2)) < 0)
1241 : return false;
1242 : }
1243 142536 : return (base2_alias_set == ref1_alias_set
1244 142536 : || alias_set_subset_of (base2_alias_set, ref1_alias_set));
1245 : }
1246 :
1247 : /* Determine if the two component references REF1 and REF2 which are
1248 : based on access types TYPE1 and TYPE2 and of which at least one is based
1249 : on an indirect reference may alias.
1250 : REF1_ALIAS_SET, BASE1_ALIAS_SET, REF2_ALIAS_SET and BASE2_ALIAS_SET
1251 : are the respective alias sets. */
1252 :
1253 : static bool
1254 2301113 : aliasing_component_refs_p (tree ref1,
1255 : alias_set_type ref1_alias_set,
1256 : alias_set_type base1_alias_set,
1257 : poly_int64 offset1, poly_int64 max_size1,
1258 : tree ref2,
1259 : alias_set_type ref2_alias_set,
1260 : alias_set_type base2_alias_set,
1261 : poly_int64 offset2, poly_int64 max_size2)
1262 : {
1263 : /* If one reference is a component references through pointers try to find a
1264 : common base and apply offset based disambiguation. This handles
1265 : for example
1266 : struct A { int i; int j; } *q;
1267 : struct B { struct A a; int k; } *p;
1268 : disambiguating q->i and p->a.j. */
1269 2301113 : tree base1, base2;
1270 2301113 : tree type1, type2;
1271 2301113 : bool maybe_match = false;
1272 2301113 : tree end_struct_ref1 = NULL, end_struct_ref2 = NULL;
1273 2301113 : bool end_struct_past_end1 = false;
1274 2301113 : bool end_struct_past_end2 = false;
1275 :
1276 : /* Choose bases and base types to search for.
1277 : The access path is as follows:
1278 : base....end_of_tbaa_ref...actual_ref
1279 : At one place in the access path may be a reference to zero sized or
1280 : trailing array.
1281 :
1282 : We generally discard the segment after end_of_tbaa_ref however
1283 : we need to be careful in case it contains zero sized or trailing array.
1284 : These may happen after reference to union and in this case we need to
1285 : not disambiguate type puning scenarios.
1286 :
1287 : We set:
1288 : base1 to point to base
1289 :
1290 : ref1 to point to end_of_tbaa_ref
1291 :
1292 : end_struct_ref1 to point the trailing reference (if it exists
1293 : in range base....end_of_tbaa_ref
1294 :
1295 : end_struct_past_end1 is true if this trailing reference occurs in
1296 : end_of_tbaa_ref...actual_ref. */
1297 2301113 : base1 = ref1;
1298 4915281 : while (handled_component_p (base1))
1299 : {
1300 : /* Generally access paths are monotous in the size of object. The
1301 : exception are trailing arrays of structures. I.e.
1302 : struct a {int array[0];};
1303 : or
1304 : struct a {int array1[0]; int array[];};
1305 : Such struct has size 0 but accesses to a.array may have non-zero size.
1306 : In this case the size of TREE_TYPE (base1) is smaller than
1307 : size of TREE_TYPE (TREE_OPERAND (base1, 0)).
1308 :
1309 : Because we compare sizes of arrays just by sizes of their elements,
1310 : we only need to care about zero sized array fields here. */
1311 2614168 : if (component_ref_to_zero_sized_trailing_array_p (base1))
1312 : {
1313 76739 : gcc_checking_assert (!end_struct_ref1);
1314 : end_struct_ref1 = base1;
1315 : }
1316 2614168 : if (ends_tbaa_access_path_p (base1))
1317 : {
1318 25230 : ref1 = TREE_OPERAND (base1, 0);
1319 25230 : if (end_struct_ref1)
1320 : {
1321 1 : end_struct_past_end1 = true;
1322 1 : end_struct_ref1 = NULL;
1323 : }
1324 : }
1325 2614168 : base1 = TREE_OPERAND (base1, 0);
1326 : }
1327 2301113 : type1 = TREE_TYPE (base1);
1328 2301113 : base2 = ref2;
1329 5375854 : while (handled_component_p (base2))
1330 : {
1331 3074741 : if (component_ref_to_zero_sized_trailing_array_p (base2))
1332 : {
1333 9138 : gcc_checking_assert (!end_struct_ref2);
1334 : end_struct_ref2 = base2;
1335 : }
1336 3074741 : if (ends_tbaa_access_path_p (base2))
1337 : {
1338 91862 : ref2 = TREE_OPERAND (base2, 0);
1339 91862 : if (end_struct_ref2)
1340 : {
1341 48 : end_struct_past_end2 = true;
1342 48 : end_struct_ref2 = NULL;
1343 : }
1344 : }
1345 3074741 : base2 = TREE_OPERAND (base2, 0);
1346 : }
1347 2301113 : type2 = TREE_TYPE (base2);
1348 :
1349 : /* Now search for the type1 in the access path of ref2. This
1350 : would be a common base for doing offset based disambiguation on.
1351 : This however only makes sense if type2 is big enough to hold type1. */
1352 2301113 : int cmp_outer = compare_type_sizes (type2, type1);
1353 :
1354 : /* If type2 is big enough to contain type1 walk its access path.
1355 : We also need to care of arrays at the end of structs that may extend
1356 : beyond the end of structure. If this occurs in the TBAA part of the
1357 : access path, we need to consider the increased type as well. */
1358 2301113 : if (cmp_outer >= 0
1359 2301113 : || (end_struct_ref2
1360 1 : && compare_type_sizes (TREE_TYPE (end_struct_ref2), type1) >= 0))
1361 : {
1362 1205012 : int res = aliasing_component_refs_walk (ref1, type1, base1,
1363 : offset1, max_size1,
1364 : end_struct_ref1,
1365 : ref2, base2, offset2, max_size2,
1366 : &maybe_match);
1367 1205012 : if (res != -1)
1368 572025 : return res;
1369 : }
1370 :
1371 : /* If we didn't find a common base, try the other way around. */
1372 1729088 : if (cmp_outer <= 0
1373 1729088 : || (end_struct_ref1
1374 60 : && compare_type_sizes (TREE_TYPE (end_struct_ref1), type2) <= 0))
1375 : {
1376 1312215 : int res = aliasing_component_refs_walk (ref2, type2, base2,
1377 : offset2, max_size2,
1378 : end_struct_ref2,
1379 : ref1, base1, offset1, max_size1,
1380 : &maybe_match);
1381 1312215 : if (res != -1)
1382 300377 : return res;
1383 : }
1384 :
1385 : /* In the following code we make an assumption that the types in access
1386 : paths do not overlap and thus accesses alias only if one path can be
1387 : continuation of another. If we was not able to decide about equivalence,
1388 : we need to give up. */
1389 1428711 : if (maybe_match)
1390 : {
1391 461959 : if (!nonoverlapping_component_refs_p (ref1, ref2))
1392 : {
1393 460151 : ++alias_stats.aliasing_component_refs_p_may_alias;
1394 460151 : return true;
1395 : }
1396 1808 : ++alias_stats.aliasing_component_refs_p_no_alias;
1397 1808 : return false;
1398 : }
1399 :
1400 966752 : if (access_path_may_continue_p (TREE_TYPE (ref1), end_struct_past_end1,
1401 : ref1_alias_set,
1402 : type2, end_struct_ref2,
1403 : base2_alias_set)
1404 966752 : || access_path_may_continue_p (TREE_TYPE (ref2), end_struct_past_end2,
1405 : ref2_alias_set,
1406 : type1, end_struct_ref1,
1407 : base1_alias_set))
1408 : {
1409 141756 : ++alias_stats.aliasing_component_refs_p_may_alias;
1410 141756 : return true;
1411 : }
1412 824996 : ++alias_stats.aliasing_component_refs_p_no_alias;
1413 824996 : return false;
1414 : }
1415 :
1416 : /* FIELD1 and FIELD2 are two fields of component refs. We assume
1417 : that bases of both component refs are either equivalent or nonoverlapping.
1418 : We do not assume that the containers of FIELD1 and FIELD2 are of the
1419 : same type or size.
1420 :
1421 : Return 0 in case the base address of component_refs are same then
1422 : FIELD1 and FIELD2 have same address. Note that FIELD1 and FIELD2
1423 : may not be of same type or size.
1424 :
1425 : Return 1 if FIELD1 and FIELD2 are non-overlapping.
1426 :
1427 : Return -1 otherwise.
1428 :
1429 : Main difference between 0 and -1 is to let
1430 : nonoverlapping_component_refs_since_match_p discover the semantically
1431 : equivalent part of the access path.
1432 :
1433 : Note that this function is used even with -fno-strict-aliasing
1434 : and makes use of no TBAA assumptions. */
1435 :
1436 : static int
1437 3286577 : nonoverlapping_component_refs_p_1 (const_tree field1, const_tree field2)
1438 : {
1439 : /* If both fields are of the same type, we could save hard work of
1440 : comparing offsets. */
1441 3286577 : tree type1 = DECL_CONTEXT (field1);
1442 3286577 : tree type2 = DECL_CONTEXT (field2);
1443 :
1444 3286577 : if (TREE_CODE (type1) == RECORD_TYPE
1445 6439135 : && DECL_BIT_FIELD_REPRESENTATIVE (field1))
1446 : field1 = DECL_BIT_FIELD_REPRESENTATIVE (field1);
1447 3286577 : if (TREE_CODE (type2) == RECORD_TYPE
1448 6439135 : && DECL_BIT_FIELD_REPRESENTATIVE (field2))
1449 : field2 = DECL_BIT_FIELD_REPRESENTATIVE (field2);
1450 :
1451 : /* ??? Bitfields can overlap at RTL level so punt on them.
1452 : FIXME: RTL expansion should be fixed by adjusting the access path
1453 : when producing MEM_ATTRs for MEMs which are wider than
1454 : the bitfields similarly as done in set_mem_attrs_minus_bitpos. */
1455 3286577 : if (DECL_BIT_FIELD (field1) && DECL_BIT_FIELD (field2))
1456 : return -1;
1457 :
1458 : /* Assume that different FIELD_DECLs never overlap within a RECORD_TYPE. */
1459 3286577 : if (type1 == type2 && TREE_CODE (type1) == RECORD_TYPE)
1460 3131631 : return field1 != field2;
1461 :
1462 : /* In common case the offsets and bit offsets will be the same.
1463 : However if frontends do not agree on the alignment, they may be
1464 : different even if they actually represent same address.
1465 : Try the common case first and if that fails calcualte the
1466 : actual bit offset. */
1467 154946 : if (tree_int_cst_equal (DECL_FIELD_OFFSET (field1),
1468 154946 : DECL_FIELD_OFFSET (field2))
1469 285213 : && tree_int_cst_equal (DECL_FIELD_BIT_OFFSET (field1),
1470 130267 : DECL_FIELD_BIT_OFFSET (field2)))
1471 : return 0;
1472 :
1473 : /* Note that it may be possible to use component_ref_field_offset
1474 : which would provide offsets as trees. However constructing and folding
1475 : trees is expensive and does not seem to be worth the compile time
1476 : cost. */
1477 :
1478 25390 : poly_uint64 offset1, offset2;
1479 25390 : poly_uint64 bit_offset1, bit_offset2;
1480 :
1481 25390 : if (poly_int_tree_p (DECL_FIELD_OFFSET (field1), &offset1)
1482 25390 : && poly_int_tree_p (DECL_FIELD_OFFSET (field2), &offset2)
1483 25390 : && poly_int_tree_p (DECL_FIELD_BIT_OFFSET (field1), &bit_offset1)
1484 50780 : && poly_int_tree_p (DECL_FIELD_BIT_OFFSET (field2), &bit_offset2))
1485 : {
1486 25390 : offset1 = (offset1 << LOG2_BITS_PER_UNIT) + bit_offset1;
1487 25390 : offset2 = (offset2 << LOG2_BITS_PER_UNIT) + bit_offset2;
1488 :
1489 25390 : if (known_eq (offset1, offset2))
1490 21963 : return 0;
1491 :
1492 25390 : poly_uint64 size1, size2;
1493 :
1494 25390 : if (poly_int_tree_p (DECL_SIZE (field1), &size1)
1495 25390 : && poly_int_tree_p (DECL_SIZE (field2), &size2)
1496 50780 : && !ranges_maybe_overlap_p (offset1, size1, offset2, size2))
1497 : return 1;
1498 : }
1499 : /* Resort to slower overlap checking by looking for matching types in
1500 : the middle of access path. */
1501 : return -1;
1502 : }
1503 :
1504 : /* Return low bound of array. Do not produce new trees
1505 : and thus do not care about particular type of integer constant
1506 : and placeholder exprs. */
1507 :
1508 : static tree
1509 17332385 : cheap_array_ref_low_bound (tree ref)
1510 : {
1511 17332385 : tree domain_type = TYPE_DOMAIN (TREE_TYPE (TREE_OPERAND (ref, 0)));
1512 :
1513 : /* Avoid expensive array_ref_low_bound.
1514 : low bound is either stored in operand2, or it is TYPE_MIN_VALUE of domain
1515 : type or it is zero. */
1516 17332385 : if (TREE_OPERAND (ref, 2))
1517 119160 : return TREE_OPERAND (ref, 2);
1518 17213225 : else if (domain_type && TYPE_MIN_VALUE (domain_type))
1519 17205617 : return TYPE_MIN_VALUE (domain_type);
1520 : else
1521 7608 : return integer_zero_node;
1522 : }
1523 :
1524 : /* REF1 and REF2 are ARRAY_REFs with either same base address or which are
1525 : completely disjoint.
1526 :
1527 : Return 1 if the refs are non-overlapping.
1528 : Return 0 if they are possibly overlapping but if so the overlap again
1529 : starts on the same address.
1530 : Return -1 otherwise. */
1531 :
1532 : int
1533 8648187 : nonoverlapping_array_refs_p (tree ref1, tree ref2)
1534 : {
1535 8648187 : tree index1 = TREE_OPERAND (ref1, 1);
1536 8648187 : tree index2 = TREE_OPERAND (ref2, 1);
1537 8648187 : tree low_bound1 = cheap_array_ref_low_bound (ref1);
1538 8648187 : tree low_bound2 = cheap_array_ref_low_bound (ref2);
1539 :
1540 : /* Handle zero offsets first: we do not need to match type size in this
1541 : case. */
1542 8648187 : if (operand_equal_p (index1, low_bound1, 0)
1543 8648187 : && operand_equal_p (index2, low_bound2, 0))
1544 : return 0;
1545 :
1546 : /* If type sizes are different, give up.
1547 :
1548 : Avoid expensive array_ref_element_size.
1549 : If operand 3 is present it denotes size in the alignmnet units.
1550 : Otherwise size is TYPE_SIZE of the element type.
1551 : Handle only common cases where types are of the same "kind". */
1552 8574294 : if ((TREE_OPERAND (ref1, 3) == NULL) != (TREE_OPERAND (ref2, 3) == NULL))
1553 : return -1;
1554 :
1555 8574294 : tree elmt_type1 = TREE_TYPE (TREE_TYPE (TREE_OPERAND (ref1, 0)));
1556 8574294 : tree elmt_type2 = TREE_TYPE (TREE_TYPE (TREE_OPERAND (ref2, 0)));
1557 :
1558 8574294 : if (TREE_OPERAND (ref1, 3))
1559 : {
1560 4218 : if (TYPE_ALIGN (elmt_type1) != TYPE_ALIGN (elmt_type2)
1561 8436 : || !operand_equal_p (TREE_OPERAND (ref1, 3),
1562 4218 : TREE_OPERAND (ref2, 3), 0))
1563 646 : return -1;
1564 : }
1565 : else
1566 : {
1567 8570076 : if (!operand_equal_p (TYPE_SIZE_UNIT (elmt_type1),
1568 8570076 : TYPE_SIZE_UNIT (elmt_type2), 0))
1569 : return -1;
1570 : }
1571 :
1572 : /* Since we know that type sizes are the same, there is no need to return
1573 : -1 after this point. Partial overlap can not be introduced. */
1574 :
1575 : /* We may need to fold trees in this case.
1576 : TODO: Handle integer constant case at least. */
1577 8565444 : if (!operand_equal_p (low_bound1, low_bound2, 0))
1578 : return 0;
1579 :
1580 8565444 : if (TREE_CODE (index1) == INTEGER_CST && TREE_CODE (index2) == INTEGER_CST)
1581 : {
1582 309531 : if (tree_int_cst_equal (index1, index2))
1583 : return 0;
1584 : return 1;
1585 : }
1586 : /* TODO: We can use VRP to further disambiguate here. */
1587 : return 0;
1588 : }
1589 :
1590 : /* Try to disambiguate REF1 and REF2 under the assumption that MATCH1 and
1591 : MATCH2 either point to the same address or are disjoint.
1592 : MATCH1 and MATCH2 are assumed to be ref in the access path of REF1 and REF2
1593 : respectively or NULL in the case we established equivalence of bases.
1594 : If PARTIAL_OVERLAP is true assume that the toplevel arrays may actually
1595 : overlap by exact multiply of their element size.
1596 :
1597 : This test works by matching the initial segment of the access path
1598 : and does not rely on TBAA thus is safe for !flag_strict_aliasing if
1599 : match was determined without use of TBAA oracle.
1600 :
1601 : Return 1 if we can determine that component references REF1 and REF2,
1602 : that are within a common DECL, cannot overlap.
1603 :
1604 : Return 0 if paths are same and thus there is nothing to disambiguate more
1605 : (i.e. there is must alias assuming there is must alias between MATCH1 and
1606 : MATCH2)
1607 :
1608 : Return -1 if we can not determine 0 or 1 - this happens when we met
1609 : non-matching types was met in the path.
1610 : In this case it may make sense to continue by other disambiguation
1611 : oracles. */
1612 :
1613 : static int
1614 9088906 : nonoverlapping_refs_since_match_p (tree match1, tree ref1,
1615 : tree match2, tree ref2,
1616 : bool partial_overlap)
1617 : {
1618 9088906 : int ntbaa1 = 0, ntbaa2 = 0;
1619 : /* Early return if there are no references to match, we do not need
1620 : to walk the access paths.
1621 :
1622 : Do not consider this as may-alias for stats - it is more useful
1623 : to have information how many disambiguations happened provided that
1624 : the query was meaningful. */
1625 :
1626 8327005 : if (match1 == ref1 || !handled_component_p (ref1)
1627 17414449 : || match2 == ref2 || !handled_component_p (ref2))
1628 : return -1;
1629 :
1630 8307843 : auto_vec<tree, 16> component_refs1;
1631 8307843 : auto_vec<tree, 16> component_refs2;
1632 :
1633 : /* Create the stack of handled components for REF1. */
1634 21141627 : while (handled_component_p (ref1) && ref1 != match1)
1635 : {
1636 : /* We use TBAA only to re-synchronize after mismatched refs. So we
1637 : do not need to truncate access path after TBAA part ends. */
1638 12833784 : if (ends_tbaa_access_path_p (ref1))
1639 : ntbaa1 = 0;
1640 : else
1641 12616975 : ntbaa1++;
1642 12833784 : component_refs1.safe_push (ref1);
1643 12833784 : ref1 = TREE_OPERAND (ref1, 0);
1644 : }
1645 :
1646 : /* Create the stack of handled components for REF2. */
1647 21091683 : while (handled_component_p (ref2) && ref2 != match2)
1648 : {
1649 12783840 : if (ends_tbaa_access_path_p (ref2))
1650 : ntbaa2 = 0;
1651 : else
1652 12545009 : ntbaa2++;
1653 12783840 : component_refs2.safe_push (ref2);
1654 12783840 : ref2 = TREE_OPERAND (ref2, 0);
1655 : }
1656 :
1657 8307843 : if (!flag_strict_aliasing)
1658 : {
1659 513260 : ntbaa1 = 0;
1660 513260 : ntbaa2 = 0;
1661 : }
1662 :
1663 8307843 : bool mem_ref1 = TREE_CODE (ref1) == MEM_REF && ref1 != match1;
1664 8307843 : bool mem_ref2 = TREE_CODE (ref2) == MEM_REF && ref2 != match2;
1665 :
1666 : /* If only one of access path starts with MEM_REF check that offset is 0
1667 : so the addresses stays the same after stripping it.
1668 : TODO: In this case we may walk the other access path until we get same
1669 : offset.
1670 :
1671 : If both starts with MEM_REF, offset has to be same. */
1672 68502 : if ((mem_ref1 && !mem_ref2 && !integer_zerop (TREE_OPERAND (ref1, 1)))
1673 8284594 : || (mem_ref2 && !mem_ref1 && !integer_zerop (TREE_OPERAND (ref2, 1)))
1674 16583233 : || (mem_ref1 && mem_ref2
1675 1114260 : && !tree_int_cst_equal (TREE_OPERAND (ref1, 1),
1676 1114260 : TREE_OPERAND (ref2, 1))))
1677 : {
1678 67010 : ++alias_stats.nonoverlapping_refs_since_match_p_may_alias;
1679 67010 : return -1;
1680 : }
1681 :
1682 : /* TARGET_MEM_REF are never wrapped in handled components, so we do not need
1683 : to handle them here at all. */
1684 8240833 : gcc_checking_assert (TREE_CODE (ref1) != TARGET_MEM_REF
1685 : && TREE_CODE (ref2) != TARGET_MEM_REF);
1686 :
1687 : /* Pop the stacks in parallel and examine the COMPONENT_REFs of the same
1688 : rank. This is sufficient because we start from the same DECL and you
1689 : cannot reference several fields at a time with COMPONENT_REFs (unlike
1690 : with ARRAY_RANGE_REFs for arrays) so you always need the same number
1691 : of them to access a sub-component, unless you're in a union, in which
1692 : case the return value will precisely be false. */
1693 10469941 : while (true)
1694 : {
1695 : /* Track if we seen unmatched ref with non-zero offset. In this case
1696 : we must look for partial overlaps. */
1697 10469941 : bool seen_unmatched_ref_p = false;
1698 :
1699 : /* First match ARRAY_REFs an try to disambiguate. */
1700 20243405 : if (!component_refs1.is_empty ()
1701 10199746 : && !component_refs2.is_empty ())
1702 : {
1703 18778599 : unsigned int narray_refs1=0, narray_refs2=0;
1704 :
1705 : /* We generally assume that both access paths starts by same sequence
1706 : of refs. However if number of array refs is not in sync, try
1707 : to recover and pop elts until number match. This helps the case
1708 : where one access path starts by array and other by element. */
1709 18778599 : for (narray_refs1 = 0; narray_refs1 < component_refs1.length ();
1710 : narray_refs1++)
1711 12469753 : if (TREE_CODE (component_refs1 [component_refs1.length()
1712 : - 1 - narray_refs1]) != ARRAY_REF)
1713 : break;
1714 :
1715 18779834 : for (narray_refs2 = 0; narray_refs2 < component_refs2.length ();
1716 : narray_refs2++)
1717 12478216 : if (TREE_CODE (component_refs2 [component_refs2.length()
1718 : - 1 - narray_refs2]) != ARRAY_REF)
1719 : break;
1720 9746093 : for (; narray_refs1 > narray_refs2; narray_refs1--)
1721 : {
1722 17388 : ref1 = component_refs1.pop ();
1723 17388 : ntbaa1--;
1724 :
1725 : /* If index is non-zero we need to check whether the reference
1726 : does not break the main invariant that bases are either
1727 : disjoint or equal. Consider the example:
1728 :
1729 : unsigned char out[][1];
1730 : out[1]="a";
1731 : out[i][0];
1732 :
1733 : Here bases out and out are same, but after removing the
1734 : [i] index, this invariant no longer holds, because
1735 : out[i] points to the middle of array out.
1736 :
1737 : TODO: If size of type of the skipped reference is an integer
1738 : multiply of the size of type of the other reference this
1739 : invariant can be verified, but even then it is not completely
1740 : safe with !flag_strict_aliasing if the other reference contains
1741 : unbounded array accesses.
1742 : See */
1743 :
1744 17388 : if (!operand_equal_p (TREE_OPERAND (ref1, 1),
1745 17388 : cheap_array_ref_low_bound (ref1), 0))
1746 : return 0;
1747 : }
1748 9728736 : for (; narray_refs2 > narray_refs1; narray_refs2--)
1749 : {
1750 18623 : ref2 = component_refs2.pop ();
1751 18623 : ntbaa2--;
1752 18623 : if (!operand_equal_p (TREE_OPERAND (ref2, 1),
1753 18623 : cheap_array_ref_low_bound (ref2), 0))
1754 : return 0;
1755 : }
1756 : /* Try to disambiguate matched arrays. */
1757 18122875 : for (unsigned int i = 0; i < narray_refs1; i++)
1758 : {
1759 17296374 : int cmp = nonoverlapping_array_refs_p (component_refs1.pop (),
1760 8648187 : component_refs2.pop ());
1761 8648187 : ntbaa1--;
1762 8648187 : ntbaa2--;
1763 8648187 : if (cmp == 1 && !partial_overlap)
1764 : {
1765 226575 : ++alias_stats
1766 226575 : .nonoverlapping_refs_since_match_p_no_alias;
1767 226575 : return 1;
1768 : }
1769 8421612 : if (cmp == -1)
1770 : {
1771 8850 : seen_unmatched_ref_p = true;
1772 : /* We can not maintain the invariant that bases are either
1773 : same or completely disjoint. However we can still recover
1774 : from type based alias analysis if we reach references to
1775 : same sizes. We do not attempt to match array sizes, so
1776 : just finish array walking and look for component refs. */
1777 8850 : if (ntbaa1 < 0 || ntbaa2 < 0)
1778 : {
1779 7985 : ++alias_stats.nonoverlapping_refs_since_match_p_may_alias;
1780 7985 : return -1;
1781 : }
1782 1804 : for (i++; i < narray_refs1; i++)
1783 : {
1784 939 : component_refs1.pop ();
1785 939 : component_refs2.pop ();
1786 939 : ntbaa1--;
1787 939 : ntbaa2--;
1788 : }
1789 : break;
1790 : }
1791 8412762 : partial_overlap = false;
1792 : }
1793 : }
1794 :
1795 : /* Next look for component_refs. */
1796 10271002 : do
1797 : {
1798 10271002 : if (component_refs1.is_empty ())
1799 : {
1800 6853826 : ++alias_stats
1801 6853826 : .nonoverlapping_refs_since_match_p_must_overlap;
1802 6853826 : return 0;
1803 : }
1804 3417176 : ref1 = component_refs1.pop ();
1805 3417176 : ntbaa1--;
1806 3417176 : if (TREE_CODE (ref1) != COMPONENT_REF)
1807 : {
1808 113542 : seen_unmatched_ref_p = true;
1809 113542 : if (ntbaa1 < 0 || ntbaa2 < 0)
1810 : {
1811 42286 : ++alias_stats.nonoverlapping_refs_since_match_p_may_alias;
1812 42286 : return -1;
1813 : }
1814 : }
1815 : }
1816 6678524 : while (!RECORD_OR_UNION_TYPE_P (TREE_TYPE (TREE_OPERAND (ref1, 0))));
1817 :
1818 3303634 : do
1819 : {
1820 3303634 : if (component_refs2.is_empty ())
1821 : {
1822 20447 : ++alias_stats
1823 20447 : .nonoverlapping_refs_since_match_p_must_overlap;
1824 20447 : return 0;
1825 : }
1826 3283187 : ref2 = component_refs2.pop ();
1827 3283187 : ntbaa2--;
1828 3283187 : if (TREE_CODE (ref2) != COMPONENT_REF)
1829 : {
1830 48 : if (ntbaa1 < 0 || ntbaa2 < 0)
1831 : {
1832 48 : ++alias_stats.nonoverlapping_refs_since_match_p_may_alias;
1833 48 : return -1;
1834 : }
1835 : seen_unmatched_ref_p = true;
1836 : }
1837 : }
1838 6566278 : while (!RECORD_OR_UNION_TYPE_P (TREE_TYPE (TREE_OPERAND (ref2, 0))));
1839 :
1840 : /* BIT_FIELD_REF and VIEW_CONVERT_EXPR are taken off the vectors
1841 : earlier. */
1842 3283139 : gcc_checking_assert (TREE_CODE (ref1) == COMPONENT_REF
1843 : && TREE_CODE (ref2) == COMPONENT_REF);
1844 :
1845 3283139 : tree field1 = TREE_OPERAND (ref1, 1);
1846 3283139 : tree field2 = TREE_OPERAND (ref2, 1);
1847 :
1848 : /* ??? We cannot simply use the type of operand #0 of the refs here
1849 : as the Fortran compiler smuggles type punning into COMPONENT_REFs
1850 : for common blocks instead of using unions like everyone else. */
1851 3283139 : tree type1 = DECL_CONTEXT (field1);
1852 3283139 : tree type2 = DECL_CONTEXT (field2);
1853 :
1854 3283139 : partial_overlap = false;
1855 :
1856 : /* If we skipped array refs on type of different sizes, we can
1857 : no longer be sure that there are not partial overlaps. */
1858 432 : if (seen_unmatched_ref_p && ntbaa1 >= 0 && ntbaa2 >= 0
1859 3283571 : && !operand_equal_p (TYPE_SIZE (type1), TYPE_SIZE (type2), 0))
1860 : {
1861 0 : ++alias_stats
1862 0 : .nonoverlapping_refs_since_match_p_may_alias;
1863 0 : return -1;
1864 : }
1865 :
1866 3283139 : int cmp = nonoverlapping_component_refs_p_1 (field1, field2);
1867 3283139 : if (cmp == -1)
1868 : {
1869 3427 : ++alias_stats
1870 3427 : .nonoverlapping_refs_since_match_p_may_alias;
1871 3427 : return -1;
1872 : }
1873 3279712 : else if (cmp == 1)
1874 : {
1875 1050604 : ++alias_stats
1876 1050604 : .nonoverlapping_refs_since_match_p_no_alias;
1877 1050604 : return 1;
1878 : }
1879 : }
1880 8307843 : }
1881 :
1882 : /* Return TYPE_UID which can be used to match record types we consider
1883 : same for TBAA purposes. */
1884 :
1885 : static inline int
1886 130642 : ncr_type_uid (const_tree field)
1887 : {
1888 : /* ??? We cannot simply use the type of operand #0 of the refs here
1889 : as the Fortran compiler smuggles type punning into COMPONENT_REFs
1890 : for common blocks instead of using unions like everyone else. */
1891 130642 : tree type = DECL_FIELD_CONTEXT (field);
1892 : /* With LTO types considered same_type_for_tbaa_p
1893 : from different translation unit may not have same
1894 : main variant. They however have same TYPE_CANONICAL. */
1895 130642 : if (TYPE_CANONICAL (type))
1896 130642 : return TYPE_UID (TYPE_CANONICAL (type));
1897 0 : return TYPE_UID (type);
1898 : }
1899 :
1900 : /* qsort compare function to sort FIELD_DECLs after their
1901 : DECL_FIELD_CONTEXT TYPE_UID. */
1902 :
1903 : static inline int
1904 57079 : ncr_compar (const void *field1_, const void *field2_)
1905 : {
1906 57079 : const_tree field1 = *(const_tree *) const_cast <void *>(field1_);
1907 57079 : const_tree field2 = *(const_tree *) const_cast <void *>(field2_);
1908 57079 : unsigned int uid1 = ncr_type_uid (field1);
1909 57079 : unsigned int uid2 = ncr_type_uid (field2);
1910 :
1911 57079 : if (uid1 < uid2)
1912 : return -1;
1913 22449 : else if (uid1 > uid2)
1914 22449 : return 1;
1915 : return 0;
1916 : }
1917 :
1918 : /* Return true if we can determine that the fields referenced cannot
1919 : overlap for any pair of objects. This relies on TBAA. */
1920 :
1921 : static bool
1922 1240684 : nonoverlapping_component_refs_p (const_tree x, const_tree y)
1923 : {
1924 : /* Early return if we have nothing to do.
1925 :
1926 : Do not consider this as may-alias for stats - it is more useful
1927 : to have information how many disambiguations happened provided that
1928 : the query was meaningful. */
1929 1240684 : if (!flag_strict_aliasing
1930 1240684 : || !x || !y
1931 164052 : || !handled_component_p (x)
1932 1240684 : || !handled_component_p (y))
1933 : return false;
1934 :
1935 101323 : auto_vec<const_tree, 16> fieldsx;
1936 319156 : while (handled_component_p (x))
1937 : {
1938 217833 : if (TREE_CODE (x) == COMPONENT_REF)
1939 : {
1940 127909 : tree field = TREE_OPERAND (x, 1);
1941 127909 : tree type = DECL_FIELD_CONTEXT (field);
1942 127909 : if (TREE_CODE (type) == RECORD_TYPE)
1943 127625 : fieldsx.safe_push (field);
1944 : }
1945 89924 : else if (ends_tbaa_access_path_p (x))
1946 2403 : fieldsx.truncate (0);
1947 217833 : x = TREE_OPERAND (x, 0);
1948 : }
1949 170758 : if (fieldsx.length () == 0)
1950 : return false;
1951 69435 : auto_vec<const_tree, 16> fieldsy;
1952 151292 : while (handled_component_p (y))
1953 : {
1954 81857 : if (TREE_CODE (y) == COMPONENT_REF)
1955 : {
1956 15892 : tree field = TREE_OPERAND (y, 1);
1957 15892 : tree type = DECL_FIELD_CONTEXT (field);
1958 15892 : if (TREE_CODE (type) == RECORD_TYPE)
1959 15608 : fieldsy.safe_push (TREE_OPERAND (y, 1));
1960 : }
1961 65965 : else if (ends_tbaa_access_path_p (y))
1962 188 : fieldsy.truncate (0);
1963 81857 : y = TREE_OPERAND (y, 0);
1964 : }
1965 69435 : if (fieldsy.length () == 0)
1966 : {
1967 61524 : ++alias_stats.nonoverlapping_component_refs_p_may_alias;
1968 61524 : return false;
1969 : }
1970 :
1971 : /* Most common case first. */
1972 7911 : if (fieldsx.length () == 1
1973 7911 : && fieldsy.length () == 1)
1974 : {
1975 9154 : if (same_type_for_tbaa (DECL_FIELD_CONTEXT (fieldsx[0]),
1976 4577 : DECL_FIELD_CONTEXT (fieldsy[0])) == 1
1977 7825 : && nonoverlapping_component_refs_p_1 (fieldsx[0], fieldsy[0]) == 1)
1978 : {
1979 1808 : ++alias_stats.nonoverlapping_component_refs_p_no_alias;
1980 1808 : return true;
1981 : }
1982 : else
1983 : {
1984 2769 : ++alias_stats.nonoverlapping_component_refs_p_may_alias;
1985 2769 : return false;
1986 : }
1987 : }
1988 :
1989 3334 : if (fieldsx.length () == 2)
1990 : {
1991 300 : if (ncr_compar (&fieldsx[0], &fieldsx[1]) == 1)
1992 162 : std::swap (fieldsx[0], fieldsx[1]);
1993 : }
1994 : else
1995 3034 : fieldsx.qsort (ncr_compar);
1996 :
1997 3334 : if (fieldsy.length () == 2)
1998 : {
1999 106 : if (ncr_compar (&fieldsy[0], &fieldsy[1]) == 1)
2000 46 : std::swap (fieldsy[0], fieldsy[1]);
2001 : }
2002 : else
2003 3228 : fieldsy.qsort (ncr_compar);
2004 :
2005 : unsigned i = 0, j = 0;
2006 8242 : do
2007 : {
2008 8242 : const_tree fieldx = fieldsx[i];
2009 8242 : const_tree fieldy = fieldsy[j];
2010 :
2011 : /* We're left with accessing different fields of a structure,
2012 : no possible overlap. */
2013 16484 : if (same_type_for_tbaa (DECL_FIELD_CONTEXT (fieldx),
2014 8242 : DECL_FIELD_CONTEXT (fieldy)) == 1
2015 8242 : && nonoverlapping_component_refs_p_1 (fieldx, fieldy) == 1)
2016 : {
2017 0 : ++alias_stats.nonoverlapping_component_refs_p_no_alias;
2018 0 : return true;
2019 : }
2020 :
2021 8242 : if (ncr_type_uid (fieldx) < ncr_type_uid (fieldy))
2022 : {
2023 2873 : i++;
2024 5746 : if (i == fieldsx.length ())
2025 : break;
2026 : }
2027 : else
2028 : {
2029 5369 : j++;
2030 10738 : if (j == fieldsy.length ())
2031 : break;
2032 : }
2033 : }
2034 : while (1);
2035 :
2036 3334 : ++alias_stats.nonoverlapping_component_refs_p_may_alias;
2037 3334 : return false;
2038 170758 : }
2039 :
2040 :
2041 : /* Return true if two memory references based on the variables BASE1
2042 : and BASE2 constrained to [OFFSET1, OFFSET1 + MAX_SIZE1) and
2043 : [OFFSET2, OFFSET2 + MAX_SIZE2) may alias. REF1 and REF2
2044 : if non-NULL are the complete memory reference trees. */
2045 :
2046 : static bool
2047 1479737038 : decl_refs_may_alias_p (tree ref1, tree base1,
2048 : poly_int64 offset1, poly_int64 max_size1,
2049 : poly_int64 size1,
2050 : tree ref2, tree base2,
2051 : poly_int64 offset2, poly_int64 max_size2,
2052 : poly_int64 size2)
2053 : {
2054 1479737038 : gcc_checking_assert (DECL_P (base1) && DECL_P (base2));
2055 :
2056 : /* If both references are based on different variables, they cannot alias. */
2057 1479737038 : if (compare_base_decls (base1, base2) == 0)
2058 : return false;
2059 :
2060 : /* If both references are based on the same variable, they cannot alias if
2061 : the accesses do not overlap. */
2062 206927059 : if (!ranges_maybe_overlap_p (offset1, max_size1, offset2, max_size2))
2063 : return false;
2064 :
2065 : /* If there is must alias, there is no use disambiguating further. */
2066 61040119 : if (known_eq (size1, max_size1) && known_eq (size2, max_size2))
2067 : return true;
2068 :
2069 : /* For components with variable position, the above test isn't sufficient,
2070 : so we disambiguate component references manually. */
2071 10493709 : if (ref1 && ref2
2072 8090972 : && handled_component_p (ref1) && handled_component_p (ref2)
2073 17705334 : && nonoverlapping_refs_since_match_p (NULL, ref1, NULL, ref2, false) == 1)
2074 : return false;
2075 :
2076 : return true;
2077 : }
2078 :
2079 : /* Return true if access with BASE is view converted.
2080 : Base must not be stripped from inner MEM_REF (&decl)
2081 : which is done by ao_ref_base and thus one extra walk
2082 : of handled components is needed. */
2083 :
2084 : bool
2085 1220148958 : view_converted_memref_p (tree base)
2086 : {
2087 1220148958 : if (TREE_CODE (base) != MEM_REF && TREE_CODE (base) != TARGET_MEM_REF)
2088 : return false;
2089 815018152 : return (same_type_for_tbaa (TREE_TYPE (base),
2090 815018152 : TREE_TYPE (TREE_TYPE (TREE_OPERAND (base, 1))))
2091 815018152 : != 1);
2092 : }
2093 :
2094 : /* Return true if an indirect reference based on *PTR1 constrained
2095 : to [OFFSET1, OFFSET1 + MAX_SIZE1) may alias a variable based on BASE2
2096 : constrained to [OFFSET2, OFFSET2 + MAX_SIZE2). *PTR1 and BASE2 have
2097 : the alias sets BASE1_ALIAS_SET and BASE2_ALIAS_SET which can be -1
2098 : in which case they are computed on-demand. REF1 and REF2
2099 : if non-NULL are the complete memory reference trees. */
2100 :
2101 : static bool
2102 299762568 : indirect_ref_may_alias_decl_p (tree ref1 ATTRIBUTE_UNUSED, tree base1,
2103 : poly_int64 offset1, poly_int64 max_size1,
2104 : poly_int64 size1,
2105 : alias_set_type ref1_alias_set,
2106 : alias_set_type base1_alias_set,
2107 : tree ref2 ATTRIBUTE_UNUSED, tree base2,
2108 : poly_int64 offset2, poly_int64 max_size2,
2109 : poly_int64 size2,
2110 : alias_set_type ref2_alias_set,
2111 : alias_set_type base2_alias_set, bool tbaa_p)
2112 : {
2113 299762568 : tree ptr1;
2114 299762568 : tree ptrtype1, dbase2;
2115 :
2116 299762568 : gcc_checking_assert ((TREE_CODE (base1) == MEM_REF
2117 : || TREE_CODE (base1) == TARGET_MEM_REF)
2118 : && DECL_P (base2));
2119 :
2120 299762568 : ptr1 = TREE_OPERAND (base1, 0);
2121 299762568 : poly_offset_int moff = mem_ref_offset (base1) << LOG2_BITS_PER_UNIT;
2122 :
2123 : /* If only one reference is based on a variable, they cannot alias if
2124 : the pointer access is beyond the extent of the variable access.
2125 : (the pointer base cannot validly point to an offset less than zero
2126 : of the variable).
2127 : ??? IVOPTs creates bases that do not honor this restriction,
2128 : so do not apply this optimization for TARGET_MEM_REFs. */
2129 299762568 : if (TREE_CODE (base1) != TARGET_MEM_REF
2130 299762568 : && !ranges_maybe_overlap_p (offset1 + moff, -1, offset2, max_size2))
2131 73181404 : return false;
2132 :
2133 : /* If the pointer based access is bigger than the variable they cannot
2134 : alias. This is similar to the check below where we use TBAA to
2135 : increase the size of the pointer based access based on the dynamic
2136 : type of a containing object we can infer from it. */
2137 226581164 : poly_int64 dsize2;
2138 226581164 : if (known_size_p (size1)
2139 211364646 : && poly_int_tree_p (DECL_SIZE (base2), &dsize2)
2140 400976233 : && known_lt (dsize2, size1))
2141 : return false;
2142 :
2143 : /* They also cannot alias if the pointer may not point to the decl. */
2144 207834055 : if (!ptr_deref_may_alias_decl_p (ptr1, base2))
2145 : return false;
2146 :
2147 : /* Disambiguations that rely on strict aliasing rules follow. */
2148 31719315 : if (!flag_strict_aliasing || !tbaa_p)
2149 : return true;
2150 :
2151 : /* If the alias set for a pointer access is zero all bets are off. */
2152 6414904 : if (base1_alias_set == 0 || base2_alias_set == 0)
2153 : return true;
2154 :
2155 : /* When we are trying to disambiguate an access with a pointer dereference
2156 : as base versus one with a decl as base we can use both the size
2157 : of the decl and its dynamic type for extra disambiguation.
2158 : ??? We do not know anything about the dynamic type of the decl
2159 : other than that its alias-set contains base2_alias_set as a subset
2160 : which does not help us here. */
2161 : /* As we know nothing useful about the dynamic type of the decl just
2162 : use the usual conflict check rather than a subset test.
2163 : ??? We could introduce -fvery-strict-aliasing when the language
2164 : does not allow decls to have a dynamic type that differs from their
2165 : static type. Then we can check
2166 : !alias_set_subset_of (base1_alias_set, base2_alias_set) instead. */
2167 1582735 : if (base1_alias_set != base2_alias_set
2168 1582735 : && !alias_sets_conflict_p (base1_alias_set, base2_alias_set))
2169 : return false;
2170 :
2171 1346678 : ptrtype1 = TREE_TYPE (TREE_OPERAND (base1, 1));
2172 :
2173 : /* If the size of the access relevant for TBAA through the pointer
2174 : is bigger than the size of the decl we can't possibly access the
2175 : decl via that pointer. */
2176 1346678 : if (/* ??? This in turn may run afoul when a decl of type T which is
2177 : a member of union type U is accessed through a pointer to
2178 : type U and sizeof T is smaller than sizeof U. */
2179 1346678 : TREE_CODE (TREE_TYPE (ptrtype1)) != UNION_TYPE
2180 1313954 : && TREE_CODE (TREE_TYPE (ptrtype1)) != QUAL_UNION_TYPE
2181 2660632 : && compare_sizes (DECL_SIZE (base2),
2182 1313954 : TYPE_SIZE (TREE_TYPE (ptrtype1))) < 0)
2183 : return false;
2184 :
2185 1306504 : if (!ref2)
2186 : return true;
2187 :
2188 : /* If the decl is accessed via a MEM_REF, reconstruct the base
2189 : we can use for TBAA and an appropriately adjusted offset. */
2190 : dbase2 = ref2;
2191 2127249 : while (handled_component_p (dbase2))
2192 888883 : dbase2 = TREE_OPERAND (dbase2, 0);
2193 1238366 : poly_int64 doffset1 = offset1;
2194 1238366 : poly_offset_int doffset2 = offset2;
2195 1238366 : if (TREE_CODE (dbase2) == MEM_REF
2196 1238366 : || TREE_CODE (dbase2) == TARGET_MEM_REF)
2197 : {
2198 912620 : doffset2 -= mem_ref_offset (dbase2) << LOG2_BITS_PER_UNIT;
2199 456310 : tree ptrtype2 = TREE_TYPE (TREE_OPERAND (dbase2, 1));
2200 : /* If second reference is view-converted, give up now. */
2201 456310 : if (same_type_for_tbaa (TREE_TYPE (dbase2), TREE_TYPE (ptrtype2)) != 1)
2202 : return true;
2203 : }
2204 :
2205 : /* If first reference is view-converted, give up now. */
2206 1134078 : if (same_type_for_tbaa (TREE_TYPE (base1), TREE_TYPE (ptrtype1)) != 1)
2207 : return true;
2208 :
2209 : /* If both references are through the same type, they do not alias
2210 : if the accesses do not overlap. This does extra disambiguation
2211 : for mixed/pointer accesses but requires strict aliasing.
2212 : For MEM_REFs we require that the component-ref offset we computed
2213 : is relative to the start of the type which we ensure by
2214 : comparing rvalue and access type and disregarding the constant
2215 : pointer offset.
2216 :
2217 : But avoid treating variable length arrays as "objects", instead assume they
2218 : can overlap by an exact multiple of their element size.
2219 : See gcc.dg/torture/alias-2.c. */
2220 1020404 : if (((TREE_CODE (base1) != TARGET_MEM_REF
2221 175296 : || (!TMR_INDEX (base1) && !TMR_INDEX2 (base1)))
2222 986682 : && (TREE_CODE (dbase2) != TARGET_MEM_REF
2223 23939 : || (!TMR_INDEX (dbase2) && !TMR_INDEX2 (dbase2))))
2224 1983170 : && same_type_for_tbaa (TREE_TYPE (base1), TREE_TYPE (dbase2)) == 1)
2225 : {
2226 339725 : bool partial_overlap = (TREE_CODE (TREE_TYPE (base1)) == ARRAY_TYPE
2227 339725 : && (TYPE_SIZE (TREE_TYPE (base1))
2228 2370 : && TREE_CODE (TYPE_SIZE (TREE_TYPE (base1)))
2229 659510 : != INTEGER_CST));
2230 339725 : if (!partial_overlap
2231 339725 : && !ranges_maybe_overlap_p (doffset1, max_size1, doffset2, max_size2))
2232 : return false;
2233 319785 : if (!ref1 || !ref2
2234 : /* If there is must alias, there is no use disambiguating further. */
2235 319785 : || (!partial_overlap
2236 307545 : && known_eq (size1, max_size1) && known_eq (size2, max_size2)))
2237 : return true;
2238 3334 : int res = nonoverlapping_refs_since_match_p (base1, ref1, base2, ref2,
2239 : partial_overlap);
2240 3334 : if (res == -1)
2241 3234 : return !nonoverlapping_component_refs_p (ref1, ref2);
2242 100 : return !res;
2243 : }
2244 :
2245 : /* Do access-path based disambiguation. */
2246 680679 : if (ref1 && ref2
2247 1149264 : && (handled_component_p (ref1) || handled_component_p (ref2)))
2248 492273 : return aliasing_component_refs_p (ref1,
2249 : ref1_alias_set, base1_alias_set,
2250 : offset1, max_size1,
2251 : ref2,
2252 : ref2_alias_set, base2_alias_set,
2253 492273 : offset2, max_size2);
2254 :
2255 : return true;
2256 : }
2257 :
2258 : /* Return true if two indirect references based on *PTR1
2259 : and *PTR2 constrained to [OFFSET1, OFFSET1 + MAX_SIZE1) and
2260 : [OFFSET2, OFFSET2 + MAX_SIZE2) may alias. *PTR1 and *PTR2 have
2261 : the alias sets BASE1_ALIAS_SET and BASE2_ALIAS_SET which can be -1
2262 : in which case they are computed on-demand. REF1 and REF2
2263 : if non-NULL are the complete memory reference trees. */
2264 :
2265 : static bool
2266 92566772 : indirect_refs_may_alias_p (tree ref1 ATTRIBUTE_UNUSED, tree base1,
2267 : poly_int64 offset1, poly_int64 max_size1,
2268 : poly_int64 size1,
2269 : alias_set_type ref1_alias_set,
2270 : alias_set_type base1_alias_set,
2271 : tree ref2 ATTRIBUTE_UNUSED, tree base2,
2272 : poly_int64 offset2, poly_int64 max_size2,
2273 : poly_int64 size2,
2274 : alias_set_type ref2_alias_set,
2275 : alias_set_type base2_alias_set, bool tbaa_p)
2276 : {
2277 92566772 : tree ptr1;
2278 92566772 : tree ptr2;
2279 92566772 : tree ptrtype1, ptrtype2;
2280 :
2281 92566772 : gcc_checking_assert ((TREE_CODE (base1) == MEM_REF
2282 : || TREE_CODE (base1) == TARGET_MEM_REF)
2283 : && (TREE_CODE (base2) == MEM_REF
2284 : || TREE_CODE (base2) == TARGET_MEM_REF));
2285 :
2286 92566772 : ptr1 = TREE_OPERAND (base1, 0);
2287 92566772 : ptr2 = TREE_OPERAND (base2, 0);
2288 :
2289 : /* If both bases are based on pointers they cannot alias if they may not
2290 : point to the same memory object or if they point to the same object
2291 : and the accesses do not overlap. */
2292 92566772 : if ((!cfun || gimple_in_ssa_p (cfun))
2293 58751156 : && operand_equal_p (ptr1, ptr2, 0)
2294 123891537 : && (((TREE_CODE (base1) != TARGET_MEM_REF
2295 1150161 : || (!TMR_INDEX (base1) && !TMR_INDEX2 (base1)))
2296 31233985 : && (TREE_CODE (base2) != TARGET_MEM_REF
2297 1050413 : || (!TMR_INDEX (base2) && !TMR_INDEX2 (base2))))
2298 109261 : || (TREE_CODE (base1) == TARGET_MEM_REF
2299 94504 : && TREE_CODE (base2) == TARGET_MEM_REF
2300 85741 : && (TMR_STEP (base1) == TMR_STEP (base2)
2301 13589 : || (TMR_STEP (base1) && TMR_STEP (base2)
2302 2835 : && operand_equal_p (TMR_STEP (base1),
2303 2835 : TMR_STEP (base2), 0)))
2304 72152 : && (TMR_INDEX (base1) == TMR_INDEX (base2)
2305 12221 : || (TMR_INDEX (base1) && TMR_INDEX (base2)
2306 10749 : && operand_equal_p (TMR_INDEX (base1),
2307 10749 : TMR_INDEX (base2), 0)))
2308 59931 : && (TMR_INDEX2 (base1) == TMR_INDEX2 (base2)
2309 0 : || (TMR_INDEX2 (base1) && TMR_INDEX2 (base2)
2310 0 : && operand_equal_p (TMR_INDEX2 (base1),
2311 0 : TMR_INDEX2 (base2), 0))))))
2312 : {
2313 31275435 : poly_offset_int moff1 = mem_ref_offset (base1) << LOG2_BITS_PER_UNIT;
2314 31275435 : poly_offset_int moff2 = mem_ref_offset (base2) << LOG2_BITS_PER_UNIT;
2315 31275435 : if (!ranges_maybe_overlap_p (offset1 + moff1, max_size1,
2316 31275435 : offset2 + moff2, max_size2))
2317 30987623 : return false;
2318 : /* If there is must alias, there is no use disambiguating further. */
2319 4118182 : if (known_eq (size1, max_size1) && known_eq (size2, max_size2))
2320 : return true;
2321 1150393 : if (ref1 && ref2)
2322 : {
2323 873365 : int res = nonoverlapping_refs_since_match_p (NULL, ref1, NULL, ref2,
2324 : false);
2325 873365 : if (res != -1)
2326 862581 : return !res;
2327 : }
2328 : }
2329 61579149 : if (!ptr_derefs_may_alias_p (ptr1, ptr2))
2330 : return false;
2331 :
2332 : /* Disambiguations that rely on strict aliasing rules follow. */
2333 38145334 : if (!flag_strict_aliasing || !tbaa_p)
2334 : return true;
2335 :
2336 15002139 : ptrtype1 = TREE_TYPE (TREE_OPERAND (base1, 1));
2337 15002139 : ptrtype2 = TREE_TYPE (TREE_OPERAND (base2, 1));
2338 :
2339 : /* If the alias set for a pointer access is zero all bets are off. */
2340 15002139 : if (base1_alias_set == 0
2341 15002139 : || base2_alias_set == 0)
2342 : return true;
2343 :
2344 : /* Do type-based disambiguation. */
2345 10167239 : if (base1_alias_set != base2_alias_set
2346 10167239 : && !alias_sets_conflict_p (base1_alias_set, base2_alias_set))
2347 : return false;
2348 :
2349 : /* If either reference is view-converted, give up now. */
2350 9430919 : if (same_type_for_tbaa (TREE_TYPE (base1), TREE_TYPE (ptrtype1)) != 1
2351 9430919 : || same_type_for_tbaa (TREE_TYPE (base2), TREE_TYPE (ptrtype2)) != 1)
2352 2933309 : return true;
2353 :
2354 : /* If both references are through the same type, they do not alias
2355 : if the accesses do not overlap. This does extra disambiguation
2356 : for mixed/pointer accesses but requires strict aliasing. */
2357 6497610 : if ((TREE_CODE (base1) != TARGET_MEM_REF
2358 1229394 : || (!TMR_INDEX (base1) && !TMR_INDEX2 (base1)))
2359 6157217 : && (TREE_CODE (base2) != TARGET_MEM_REF
2360 1115159 : || (!TMR_INDEX (base2) && !TMR_INDEX2 (base2)))
2361 12522431 : && same_type_for_tbaa (TREE_TYPE (ptrtype1),
2362 6024821 : TREE_TYPE (ptrtype2)) == 1)
2363 : {
2364 : /* But avoid treating arrays as "objects", instead assume they
2365 : can overlap by an exact multiple of their element size.
2366 : See gcc.dg/torture/alias-2.c. */
2367 4022830 : bool partial_overlap = TREE_CODE (TREE_TYPE (ptrtype1)) == ARRAY_TYPE;
2368 :
2369 4022830 : if (!partial_overlap
2370 4022830 : && !ranges_maybe_overlap_p (offset1, max_size1, offset2, max_size2))
2371 : return false;
2372 3674460 : if (!ref1 || !ref2
2373 3674460 : || (!partial_overlap
2374 3097902 : && known_eq (size1, max_size1) && known_eq (size2, max_size2)))
2375 : return true;
2376 194176 : int res = nonoverlapping_refs_since_match_p (base1, ref1, base2, ref2,
2377 : partial_overlap);
2378 194176 : if (res == -1)
2379 70489 : return !nonoverlapping_component_refs_p (ref1, ref2);
2380 123687 : return !res;
2381 : }
2382 :
2383 : /* Do access-path based disambiguation. */
2384 2474780 : if (ref1 && ref2
2385 3598080 : && (handled_component_p (ref1) || handled_component_p (ref2)))
2386 1808840 : return aliasing_component_refs_p (ref1,
2387 : ref1_alias_set, base1_alias_set,
2388 : offset1, max_size1,
2389 : ref2,
2390 : ref2_alias_set, base2_alias_set,
2391 1808840 : offset2, max_size2);
2392 :
2393 : return true;
2394 : }
2395 :
2396 : /* Return true, if the two memory references REF1 and REF2 may alias. */
2397 :
2398 : static bool
2399 1948708427 : refs_may_alias_p_2 (ao_ref *ref1, ao_ref *ref2, bool tbaa_p)
2400 : {
2401 1948708427 : tree base1, base2;
2402 1948708427 : poly_int64 offset1 = 0, offset2 = 0;
2403 1948708427 : poly_int64 max_size1 = -1, max_size2 = -1;
2404 1948708427 : bool var1_p, var2_p, ind1_p, ind2_p;
2405 :
2406 1948708427 : gcc_checking_assert ((!ref1->ref
2407 : || TREE_CODE (ref1->ref) == SSA_NAME
2408 : || DECL_P (ref1->ref)
2409 : || TREE_CODE (ref1->ref) == STRING_CST
2410 : || handled_component_p (ref1->ref)
2411 : || TREE_CODE (ref1->ref) == MEM_REF
2412 : || TREE_CODE (ref1->ref) == TARGET_MEM_REF
2413 : || TREE_CODE (ref1->ref) == WITH_SIZE_EXPR)
2414 : && (!ref2->ref
2415 : || TREE_CODE (ref2->ref) == SSA_NAME
2416 : || DECL_P (ref2->ref)
2417 : || TREE_CODE (ref2->ref) == STRING_CST
2418 : || handled_component_p (ref2->ref)
2419 : || TREE_CODE (ref2->ref) == MEM_REF
2420 : || TREE_CODE (ref2->ref) == TARGET_MEM_REF
2421 : || TREE_CODE (ref2->ref) == WITH_SIZE_EXPR));
2422 :
2423 : /* Decompose the references into their base objects and the access. */
2424 1948708427 : base1 = ao_ref_base (ref1);
2425 1948708427 : offset1 = ref1->offset;
2426 1948708427 : max_size1 = ref1->max_size;
2427 1948708427 : base2 = ao_ref_base (ref2);
2428 1948708427 : offset2 = ref2->offset;
2429 1948708427 : max_size2 = ref2->max_size;
2430 :
2431 : /* We can end up with registers or constants as bases for example from
2432 : *D.1663_44 = VIEW_CONVERT_EXPR<struct DB_LSN>(__tmp$B0F64_59);
2433 : which is seen as a struct copy. */
2434 1948708427 : if (TREE_CODE (base1) == SSA_NAME
2435 1948707115 : || TREE_CODE (base1) == CONST_DECL
2436 1946766995 : || TREE_CODE (base1) == CONSTRUCTOR
2437 1946766995 : || TREE_CODE (base1) == ADDR_EXPR
2438 1946766995 : || CONSTANT_CLASS_P (base1)
2439 1940364735 : || TREE_CODE (base2) == SSA_NAME
2440 1940364735 : || TREE_CODE (base2) == CONST_DECL
2441 1940267709 : || TREE_CODE (base2) == CONSTRUCTOR
2442 1940267709 : || TREE_CODE (base2) == ADDR_EXPR
2443 1940267709 : || CONSTANT_CLASS_P (base2))
2444 : return false;
2445 :
2446 : /* Two volatile accesses always conflict. */
2447 1940224438 : if (ref1->volatile_p
2448 5867706 : && ref2->volatile_p)
2449 : return true;
2450 :
2451 : /* refN->ref may convey size information, do not confuse our workers
2452 : with that but strip it - ao_ref_base took it into account already. */
2453 1936602840 : tree ref1ref = ref1->ref;
2454 1936602840 : if (ref1ref && TREE_CODE (ref1ref) == WITH_SIZE_EXPR)
2455 162 : ref1ref = TREE_OPERAND (ref1ref, 0);
2456 1936602840 : tree ref2ref = ref2->ref;
2457 1936602840 : if (ref2ref && TREE_CODE (ref2ref) == WITH_SIZE_EXPR)
2458 0 : ref2ref = TREE_OPERAND (ref2ref, 0);
2459 :
2460 : /* Defer to simple offset based disambiguation if we have
2461 : references based on two decls. Do this before defering to
2462 : TBAA to handle must-alias cases in conformance with the
2463 : GCC extension of allowing type-punning through unions. */
2464 1936602840 : var1_p = DECL_P (base1);
2465 1936602840 : var2_p = DECL_P (base2);
2466 1936602840 : if (var1_p && var2_p)
2467 1479737038 : return decl_refs_may_alias_p (ref1ref, base1, offset1, max_size1,
2468 : ref1->size,
2469 : ref2ref, base2, offset2, max_size2,
2470 1479737038 : ref2->size);
2471 :
2472 : /* We can end up referring to code via function and label decls.
2473 : As we likely do not properly track code aliases conservatively
2474 : bail out. */
2475 456865802 : if (TREE_CODE (base1) == FUNCTION_DECL
2476 456865802 : || TREE_CODE (base1) == LABEL_DECL
2477 455923593 : || TREE_CODE (base2) == FUNCTION_DECL
2478 455909564 : || TREE_CODE (base2) == LABEL_DECL)
2479 : return true;
2480 :
2481 : /* Handle restrict based accesses.
2482 : ??? ao_ref_base strips inner MEM_REF [&decl], recover from that
2483 : here. */
2484 455909564 : tree rbase1 = base1;
2485 455909564 : tree rbase2 = base2;
2486 455909564 : if (var1_p)
2487 : {
2488 224353710 : rbase1 = ref1ref;
2489 224353710 : if (rbase1)
2490 294522134 : while (handled_component_p (rbase1))
2491 107874877 : rbase1 = TREE_OPERAND (rbase1, 0);
2492 : }
2493 455909564 : if (var2_p)
2494 : {
2495 114870924 : rbase2 = ref2ref;
2496 114870924 : if (rbase2)
2497 189465875 : while (handled_component_p (rbase2))
2498 82226209 : rbase2 = TREE_OPERAND (rbase2, 0);
2499 : }
2500 455909564 : if (rbase1 && rbase2
2501 410571853 : && (TREE_CODE (rbase1) == MEM_REF || TREE_CODE (rbase1) == TARGET_MEM_REF)
2502 257941728 : && (TREE_CODE (rbase2) == MEM_REF || TREE_CODE (rbase2) == TARGET_MEM_REF)
2503 : /* If the accesses are in the same restrict clique... */
2504 180988818 : && MR_DEPENDENCE_CLIQUE (rbase1) == MR_DEPENDENCE_CLIQUE (rbase2)
2505 : /* But based on different pointers they do not alias. */
2506 606624888 : && MR_DEPENDENCE_BASE (rbase1) != MR_DEPENDENCE_BASE (rbase2))
2507 : return false;
2508 :
2509 440266812 : ind1_p = (TREE_CODE (base1) == MEM_REF
2510 440266812 : || TREE_CODE (base1) == TARGET_MEM_REF);
2511 440266812 : ind2_p = (TREE_CODE (base2) == MEM_REF
2512 440266812 : || TREE_CODE (base2) == TARGET_MEM_REF);
2513 :
2514 : /* Canonicalize the pointer-vs-decl case. */
2515 440266812 : if (ind1_p && var2_p)
2516 : {
2517 113553283 : std::swap (offset1, offset2);
2518 113553283 : std::swap (max_size1, max_size2);
2519 113553283 : std::swap (base1, base2);
2520 113553283 : std::swap (ref1, ref2);
2521 113553283 : std::swap (ref1ref, ref2ref);
2522 113553283 : var1_p = true;
2523 113553283 : ind1_p = false;
2524 113553283 : var2_p = false;
2525 113553283 : ind2_p = true;
2526 : }
2527 :
2528 : /* First defer to TBAA if possible. */
2529 440266812 : if (tbaa_p
2530 194896980 : && flag_strict_aliasing
2531 567243971 : && !alias_sets_conflict_p (ao_ref_alias_set (ref1),
2532 : ao_ref_alias_set (ref2)))
2533 : return false;
2534 :
2535 : /* If the reference is based on a pointer that points to memory
2536 : that may not be written to then the other reference cannot possibly
2537 : clobber it. */
2538 392885894 : if ((TREE_CODE (TREE_OPERAND (base2, 0)) == SSA_NAME
2539 391560064 : && SSA_NAME_POINTS_TO_READONLY_MEMORY (TREE_OPERAND (base2, 0)))
2540 784051214 : || (ind1_p
2541 92728582 : && TREE_CODE (TREE_OPERAND (base1, 0)) == SSA_NAME
2542 92535046 : && SSA_NAME_POINTS_TO_READONLY_MEMORY (TREE_OPERAND (base1, 0))))
2543 : return false;
2544 :
2545 : /* Dispatch to the pointer-vs-decl or pointer-vs-pointer disambiguators. */
2546 392329340 : if (var1_p && ind2_p)
2547 299762568 : return indirect_ref_may_alias_decl_p (ref2ref, base2,
2548 : offset2, max_size2, ref2->size,
2549 : ao_ref_alias_set (ref2),
2550 : ao_ref_base_alias_set (ref2),
2551 : ref1ref, base1,
2552 : offset1, max_size1, ref1->size,
2553 : ao_ref_alias_set (ref1),
2554 : ao_ref_base_alias_set (ref1),
2555 299762568 : tbaa_p);
2556 92566772 : else if (ind1_p && ind2_p)
2557 92566772 : return indirect_refs_may_alias_p (ref1ref, base1,
2558 : offset1, max_size1, ref1->size,
2559 : ao_ref_alias_set (ref1),
2560 : ao_ref_base_alias_set (ref1),
2561 : ref2ref, base2,
2562 : offset2, max_size2, ref2->size,
2563 : ao_ref_alias_set (ref2),
2564 : ao_ref_base_alias_set (ref2),
2565 92566772 : tbaa_p);
2566 :
2567 0 : gcc_unreachable ();
2568 : }
2569 :
2570 : /* Return true, if the two memory references REF1 and REF2 may alias
2571 : and update statistics. */
2572 :
2573 : bool
2574 1948708427 : refs_may_alias_p_1 (ao_ref *ref1, ao_ref *ref2, bool tbaa_p)
2575 : {
2576 1948708427 : bool res = refs_may_alias_p_2 (ref1, ref2, tbaa_p);
2577 1948708427 : if (res)
2578 135762134 : ++alias_stats.refs_may_alias_p_may_alias;
2579 : else
2580 1812946293 : ++alias_stats.refs_may_alias_p_no_alias;
2581 1948708427 : return res;
2582 : }
2583 :
2584 : static bool
2585 61136914 : refs_may_alias_p (tree ref1, ao_ref *ref2, bool tbaa_p)
2586 : {
2587 61136914 : ao_ref r1;
2588 61136914 : ao_ref_init (&r1, ref1);
2589 61136914 : return refs_may_alias_p_1 (&r1, ref2, tbaa_p);
2590 : }
2591 :
2592 : bool
2593 1052123 : refs_may_alias_p (tree ref1, tree ref2, bool tbaa_p)
2594 : {
2595 1052123 : ao_ref r1, r2;
2596 1052123 : ao_ref_init (&r1, ref1);
2597 1052123 : ao_ref_init (&r2, ref2);
2598 1052123 : return refs_may_alias_p_1 (&r1, &r2, tbaa_p);
2599 : }
2600 :
2601 : /* Returns true if there is a anti-dependence for the STORE that
2602 : executes after the LOAD. */
2603 :
2604 : bool
2605 480463 : refs_anti_dependent_p (tree load, tree store)
2606 : {
2607 480463 : ao_ref r1, r2;
2608 480463 : ao_ref_init (&r1, load);
2609 480463 : ao_ref_init (&r2, store);
2610 480463 : return refs_may_alias_p_1 (&r1, &r2, false);
2611 : }
2612 :
2613 : /* Returns true if there is a output dependence for the stores
2614 : STORE1 and STORE2. */
2615 :
2616 : bool
2617 2890552 : refs_output_dependent_p (tree store1, tree store2)
2618 : {
2619 2890552 : ao_ref r1, r2;
2620 2890552 : ao_ref_init (&r1, store1);
2621 2890552 : ao_ref_init (&r2, store2);
2622 2890552 : return refs_may_alias_p_1 (&r1, &r2, false);
2623 : }
2624 :
2625 : /* Returns true if and only if REF may alias any access stored in TT.
2626 : IF TBAA_P is true, use TBAA oracle. */
2627 :
2628 : static bool
2629 43453967 : modref_may_conflict (const gcall *stmt,
2630 : modref_tree <alias_set_type> *tt, ao_ref *ref, bool tbaa_p)
2631 : {
2632 43453967 : alias_set_type base_set, ref_set;
2633 43453967 : bool global_memory_ok = false;
2634 :
2635 43453967 : if (tt->every_base)
2636 : return true;
2637 :
2638 8677947 : if (!dbg_cnt (ipa_mod_ref))
2639 : return true;
2640 :
2641 8677947 : base_set = ao_ref_base_alias_set (ref);
2642 :
2643 8677947 : ref_set = ao_ref_alias_set (ref);
2644 :
2645 8677947 : int num_tests = 0, max_tests = param_modref_max_tests;
2646 35526660 : for (auto base_node : tt->bases)
2647 : {
2648 13611193 : if (tbaa_p && flag_strict_aliasing)
2649 : {
2650 10332181 : if (num_tests >= max_tests)
2651 : return true;
2652 10332181 : alias_stats.modref_tests++;
2653 10332181 : if (!alias_sets_conflict_p (base_set, base_node->base))
2654 3544193 : continue;
2655 6787988 : num_tests++;
2656 : }
2657 :
2658 10067000 : if (base_node->every_ref)
2659 : return true;
2660 :
2661 38068567 : for (auto ref_node : base_node->refs)
2662 : {
2663 : /* Do not repeat same test as before. */
2664 11592543 : if ((ref_set != base_set || base_node->base != ref_node->ref)
2665 6837472 : && tbaa_p && flag_strict_aliasing)
2666 : {
2667 4321419 : if (num_tests >= max_tests)
2668 : return true;
2669 4290147 : alias_stats.modref_tests++;
2670 4290147 : if (!alias_sets_conflict_p (ref_set, ref_node->ref))
2671 1093008 : continue;
2672 3197139 : num_tests++;
2673 : }
2674 :
2675 10468263 : if (ref_node->every_access)
2676 : return true;
2677 :
2678 : /* TBAA checks did not disambiguate, try individual accesses. */
2679 33477426 : for (auto access_node : ref_node->accesses)
2680 : {
2681 9496908 : if (num_tests >= max_tests)
2682 1808526 : return true;
2683 :
2684 9496908 : if (access_node.parm_index == MODREF_GLOBAL_MEMORY_PARM)
2685 : {
2686 1907611 : if (global_memory_ok)
2687 1128245 : continue;
2688 1907611 : if (ref_may_alias_global_p (ref, true))
2689 : return true;
2690 1103948 : global_memory_ok = true;
2691 1103948 : num_tests++;
2692 1103948 : continue;
2693 : }
2694 :
2695 7589297 : tree arg = access_node.get_call_arg (stmt);
2696 7589297 : if (!arg)
2697 : return true;
2698 :
2699 7588235 : alias_stats.modref_baseptr_tests++;
2700 :
2701 7588235 : if (integer_zerop (arg) && flag_delete_null_pointer_checks)
2702 24297 : continue;
2703 :
2704 : /* PTA oracle will be unhapy of arg is not an pointer. */
2705 7563938 : if (!POINTER_TYPE_P (TREE_TYPE (arg)))
2706 : return true;
2707 :
2708 : /* If we don't have base pointer, give up. */
2709 7563938 : if (!ref->ref && !ref->base)
2710 0 : continue;
2711 :
2712 7563938 : ao_ref ref2;
2713 7563938 : if (access_node.get_ao_ref (stmt, &ref2))
2714 : {
2715 5788536 : ref2.ref_alias_set = ref_node->ref;
2716 5788536 : ref2.base_alias_set = base_node->base;
2717 5788536 : if (refs_may_alias_p_1 (&ref2, ref, tbaa_p))
2718 : return true;
2719 : }
2720 1775402 : else if (ptr_deref_may_alias_ref_p_1 (arg, ref))
2721 : return true;
2722 :
2723 6560137 : num_tests++;
2724 : }
2725 : }
2726 : }
2727 : return false;
2728 : }
2729 :
2730 : /* Check if REF conflicts with call using "fn spec" attribute.
2731 : If CLOBBER is true we are checking for writes, otherwise check loads.
2732 :
2733 : Return 0 if there are no conflicts (except for possible function call
2734 : argument reads), 1 if there are conflicts and -1 if we can not decide by
2735 : fn spec. */
2736 :
2737 : static int
2738 150346954 : check_fnspec (gcall *call, ao_ref *ref, bool clobber)
2739 : {
2740 150346954 : attr_fnspec fnspec = gimple_call_fnspec (call);
2741 150346954 : if (fnspec.known_p ())
2742 : {
2743 76548164 : if (clobber
2744 76548164 : ? !fnspec.global_memory_written_p ()
2745 8846813 : : !fnspec.global_memory_read_p ())
2746 : {
2747 92680863 : for (unsigned int i = 0; i < gimple_call_num_args (call); i++)
2748 90201259 : if (POINTER_TYPE_P (TREE_TYPE (gimple_call_arg (call, i)))
2749 63987649 : && (!fnspec.arg_specified_p (i)
2750 37717527 : || (clobber ? fnspec.arg_maybe_written_p (i)
2751 3847062 : : fnspec.arg_maybe_read_p (i))))
2752 : {
2753 23265483 : ao_ref dref;
2754 23265483 : tree size = NULL_TREE;
2755 23265483 : unsigned int size_arg;
2756 :
2757 23265483 : if (!fnspec.arg_specified_p (i))
2758 : ;
2759 23262124 : else if (fnspec.arg_max_access_size_given_by_arg_p
2760 23262124 : (i, &size_arg))
2761 15802545 : size = gimple_call_arg (call, size_arg);
2762 7459579 : else if (fnspec.arg_access_size_given_by_type_p (i))
2763 : {
2764 34655 : tree callee = gimple_call_fndecl (call);
2765 34655 : tree t = TYPE_ARG_TYPES (TREE_TYPE (callee));
2766 :
2767 70620 : for (unsigned int p = 0; p < i; p++)
2768 35965 : t = TREE_CHAIN (t);
2769 34655 : size = TYPE_SIZE_UNIT (TREE_TYPE (TREE_VALUE (t)));
2770 : }
2771 15837200 : poly_int64 size_hwi;
2772 15837200 : if (size
2773 15837200 : && poly_int_tree_p (size, &size_hwi)
2774 29125728 : && coeffs_in_range_p (size_hwi, 0,
2775 : HOST_WIDE_INT_MAX / BITS_PER_UNIT))
2776 : {
2777 13286976 : size_hwi = size_hwi * BITS_PER_UNIT;
2778 13286976 : ao_ref_init_from_ptr_and_range (&dref,
2779 : gimple_call_arg (call, i),
2780 : true, 0, -1, size_hwi);
2781 : }
2782 : else
2783 9978507 : ao_ref_init_from_ptr_and_range (&dref,
2784 : gimple_call_arg (call, i),
2785 : false, 0, -1, -1);
2786 23265483 : if (refs_may_alias_p_1 (&dref, ref, false))
2787 4671013 : return 1;
2788 : }
2789 28746367 : if (clobber
2790 25047924 : && fnspec.errno_maybe_written_p ()
2791 7401584 : && flag_errno_math
2792 30250278 : && targetm.ref_may_alias_errno (ref))
2793 : return 1;
2794 28730988 : return 0;
2795 : }
2796 : }
2797 :
2798 : /* FIXME: we should handle barriers more consistently, but for now leave the
2799 : check here. */
2800 116929574 : if (gimple_call_builtin_p (call, BUILT_IN_NORMAL))
2801 6539051 : switch (DECL_FUNCTION_CODE (gimple_call_fndecl (call)))
2802 : {
2803 : /* __sync_* builtins and some OpenMP builtins act as threading
2804 : barriers. */
2805 : #undef DEF_SYNC_BUILTIN
2806 : #define DEF_SYNC_BUILTIN(ENUM, NAME, TYPE, ATTRS) case ENUM:
2807 : #include "sync-builtins.def"
2808 : #undef DEF_SYNC_BUILTIN
2809 : case BUILT_IN_GOMP_ATOMIC_START:
2810 : case BUILT_IN_GOMP_ATOMIC_END:
2811 : case BUILT_IN_GOMP_BARRIER:
2812 : case BUILT_IN_GOMP_BARRIER_CANCEL:
2813 : case BUILT_IN_GOMP_TASKWAIT:
2814 : case BUILT_IN_GOMP_TASKGROUP_END:
2815 : case BUILT_IN_GOMP_CRITICAL_START:
2816 : case BUILT_IN_GOMP_CRITICAL_END:
2817 : case BUILT_IN_GOMP_CRITICAL_NAME_START:
2818 : case BUILT_IN_GOMP_CRITICAL_NAME_END:
2819 : case BUILT_IN_GOMP_LOOP_END:
2820 : case BUILT_IN_GOMP_LOOP_END_CANCEL:
2821 : case BUILT_IN_GOMP_ORDERED_START:
2822 : case BUILT_IN_GOMP_ORDERED_END:
2823 : case BUILT_IN_GOMP_SECTIONS_END:
2824 : case BUILT_IN_GOMP_SECTIONS_END_CANCEL:
2825 : case BUILT_IN_GOMP_SINGLE_COPY_START:
2826 : case BUILT_IN_GOMP_SINGLE_COPY_END:
2827 : return 1;
2828 :
2829 : default:
2830 : return -1;
2831 : }
2832 : return -1;
2833 : }
2834 :
2835 : /* If the call CALL may use the memory reference REF return true,
2836 : otherwise return false. */
2837 :
2838 : static bool
2839 44142359 : ref_maybe_used_by_call_p_1 (gcall *call, ao_ref *ref, bool tbaa_p)
2840 : {
2841 44142359 : tree base, callee;
2842 44142359 : unsigned i;
2843 44142359 : int flags = gimple_call_flags (call);
2844 :
2845 44142359 : if (flags & (ECF_CONST|ECF_NOVOPS))
2846 246579 : goto process_args;
2847 :
2848 : /* A call that is not without side-effects might involve volatile
2849 : accesses and thus conflicts with all other volatile accesses. */
2850 43895780 : if (ref->volatile_p)
2851 : return true;
2852 :
2853 43895605 : if (gimple_call_internal_p (call))
2854 59076 : switch (gimple_call_internal_fn (call))
2855 : {
2856 : case IFN_MASK_STORE:
2857 : case IFN_SCATTER_STORE:
2858 : case IFN_MASK_SCATTER_STORE:
2859 : case IFN_LEN_STORE:
2860 : case IFN_MASK_LEN_STORE:
2861 : return false;
2862 0 : case IFN_MASK_STORE_LANES:
2863 0 : case IFN_MASK_LEN_STORE_LANES:
2864 0 : goto process_args;
2865 839 : case IFN_MASK_LOAD:
2866 839 : case IFN_LEN_LOAD:
2867 839 : case IFN_MASK_LEN_LOAD:
2868 839 : case IFN_MASK_LOAD_LANES:
2869 839 : case IFN_MASK_LEN_LOAD_LANES:
2870 839 : {
2871 839 : ao_ref rhs_ref;
2872 839 : tree lhs = gimple_call_lhs (call);
2873 839 : if (lhs)
2874 : {
2875 839 : ao_ref_init_from_ptr_and_size (&rhs_ref,
2876 : gimple_call_arg (call, 0),
2877 839 : TYPE_SIZE_UNIT (TREE_TYPE (lhs)));
2878 : /* We cannot make this a known-size access since otherwise
2879 : we disambiguate against refs to decls that are smaller. */
2880 839 : rhs_ref.size = -1;
2881 1678 : rhs_ref.ref_alias_set = rhs_ref.base_alias_set
2882 1678 : = tbaa_p ? get_deref_alias_set (TREE_TYPE
2883 : (gimple_call_arg (call, 1))) : 0;
2884 839 : return refs_may_alias_p_1 (ref, &rhs_ref, tbaa_p);
2885 : }
2886 0 : break;
2887 : }
2888 : default:;
2889 : }
2890 :
2891 43889173 : callee = gimple_call_fndecl (call);
2892 43889173 : if (callee != NULL_TREE)
2893 : {
2894 42413855 : struct cgraph_node *node = cgraph_node::get (callee);
2895 : /* We can not safely optimize based on summary of calle if it does
2896 : not always bind to current def: it is possible that memory load
2897 : was optimized out earlier and the interposed variant may not be
2898 : optimized this way. */
2899 42413855 : if (node && node->binds_to_current_def_p ())
2900 : {
2901 5364284 : modref_summary *summary = get_modref_function_summary (node);
2902 5364284 : if (summary && !summary->calls_interposable)
2903 : {
2904 3001726 : if (!modref_may_conflict (call, summary->loads, ref, tbaa_p))
2905 : {
2906 631333 : alias_stats.modref_use_no_alias++;
2907 631333 : if (dump_file && (dump_flags & TDF_DETAILS))
2908 : {
2909 24 : fprintf (dump_file,
2910 : "ipa-modref: call stmt ");
2911 24 : print_gimple_stmt (dump_file, call, 0);
2912 24 : fprintf (dump_file,
2913 : "ipa-modref: call to %s does not use ",
2914 : node->dump_name ());
2915 24 : if (!ref->ref && ref->base)
2916 : {
2917 3 : fprintf (dump_file, "base: ");
2918 3 : print_generic_expr (dump_file, ref->base);
2919 : }
2920 21 : else if (ref->ref)
2921 : {
2922 21 : fprintf (dump_file, "ref: ");
2923 21 : print_generic_expr (dump_file, ref->ref);
2924 : }
2925 24 : fprintf (dump_file, " alias sets: %i->%i\n",
2926 : ao_ref_base_alias_set (ref),
2927 : ao_ref_alias_set (ref));
2928 : }
2929 631333 : goto process_args;
2930 : }
2931 2370393 : alias_stats.modref_use_may_alias++;
2932 : }
2933 : }
2934 : }
2935 :
2936 43257840 : base = ao_ref_base (ref);
2937 43257840 : if (!base)
2938 : return true;
2939 :
2940 : /* If the reference is based on a decl that is not aliased the call
2941 : cannot possibly use it. */
2942 43257840 : if (DECL_P (base)
2943 38553305 : && !may_be_aliased (base)
2944 : /* But local statics can be used through recursion. */
2945 64299262 : && !is_global_var (base))
2946 20757414 : goto process_args;
2947 :
2948 22500426 : if (int res = check_fnspec (call, ref, false))
2949 : {
2950 18801983 : if (res == 1)
2951 : return true;
2952 : }
2953 : else
2954 3698443 : goto process_args;
2955 :
2956 : /* Check if base is a global static variable that is not read
2957 : by the function. */
2958 18290363 : if (callee != NULL_TREE && VAR_P (base) && TREE_STATIC (base))
2959 : {
2960 971433 : struct cgraph_node *node = cgraph_node::get (callee);
2961 971433 : bitmap read;
2962 971433 : int id;
2963 :
2964 : /* FIXME: Callee can be an OMP builtin that does not have a call graph
2965 : node yet. We should enforce that there are nodes for all decls in the
2966 : IL and remove this check instead. */
2967 971433 : if (node
2968 970791 : && (id = ipa_reference_var_uid (base)) != -1
2969 138023 : && (read = ipa_reference_get_read_global (node))
2970 987768 : && !bitmap_bit_p (read, id))
2971 11336 : goto process_args;
2972 : }
2973 :
2974 : /* Check if the base variable is call-used. */
2975 18279027 : if (DECL_P (base))
2976 : {
2977 14922470 : if (pt_solution_includes (gimple_call_use_set (call), base))
2978 : return true;
2979 : }
2980 3356557 : else if ((TREE_CODE (base) == MEM_REF
2981 3356557 : || TREE_CODE (base) == TARGET_MEM_REF)
2982 3356557 : && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
2983 : {
2984 3356326 : struct ptr_info_def *pi = SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0));
2985 3356326 : if (!pi)
2986 : return true;
2987 :
2988 3347367 : if (pt_solutions_intersect (gimple_call_use_set (call), &pi->pt))
2989 : return true;
2990 : }
2991 : else
2992 : return true;
2993 :
2994 : /* Inspect call arguments for passed-by-value aliases. */
2995 : process_args:
2996 82697241 : for (i = 0; i < gimple_call_num_args (call); ++i)
2997 : {
2998 58163645 : tree op = gimple_call_arg (call, i);
2999 58163645 : int flags = gimple_call_arg_flags (call, i);
3000 :
3001 58163645 : if (flags & (EAF_UNUSED | EAF_NO_DIRECT_READ))
3002 708514 : continue;
3003 :
3004 57455131 : if (TREE_CODE (op) == WITH_SIZE_EXPR)
3005 504 : op = TREE_OPERAND (op, 0);
3006 :
3007 57455131 : if (TREE_CODE (op) != SSA_NAME
3008 57455131 : && !is_gimple_min_invariant (op))
3009 : {
3010 10157259 : ao_ref r;
3011 10157259 : ao_ref_init (&r, op);
3012 10157259 : if (refs_may_alias_p_1 (&r, ref, tbaa_p))
3013 4121270 : return true;
3014 : }
3015 : }
3016 :
3017 : return false;
3018 : }
3019 :
3020 : static bool
3021 44132838 : ref_maybe_used_by_call_p (gcall *call, ao_ref *ref, bool tbaa_p)
3022 : {
3023 44132838 : bool res;
3024 44132838 : res = ref_maybe_used_by_call_p_1 (call, ref, tbaa_p);
3025 44132838 : if (res)
3026 19596514 : ++alias_stats.ref_maybe_used_by_call_p_may_alias;
3027 : else
3028 24536324 : ++alias_stats.ref_maybe_used_by_call_p_no_alias;
3029 44132838 : return res;
3030 : }
3031 :
3032 :
3033 : /* If the statement STMT may use the memory reference REF return
3034 : true, otherwise return false. */
3035 :
3036 : bool
3037 352788226 : ref_maybe_used_by_stmt_p (gimple *stmt, ao_ref *ref, bool tbaa_p)
3038 : {
3039 352788226 : if (is_gimple_assign (stmt))
3040 : {
3041 302662101 : tree rhs;
3042 :
3043 : /* All memory assign statements are single. */
3044 302662101 : if (!gimple_assign_single_p (stmt))
3045 : return false;
3046 :
3047 302662101 : rhs = gimple_assign_rhs1 (stmt);
3048 302662101 : if (is_gimple_reg (rhs)
3049 246708723 : || is_gimple_min_invariant (rhs)
3050 397885609 : || gimple_assign_rhs_code (stmt) == CONSTRUCTOR)
3051 243590324 : return false;
3052 :
3053 59071777 : return refs_may_alias_p (rhs, ref, tbaa_p);
3054 : }
3055 50126125 : else if (is_gimple_call (stmt))
3056 44132838 : return ref_maybe_used_by_call_p (as_a <gcall *> (stmt), ref, tbaa_p);
3057 5993287 : else if (greturn *return_stmt = dyn_cast <greturn *> (stmt))
3058 : {
3059 5239421 : tree retval = gimple_return_retval (return_stmt);
3060 5239421 : if (retval
3061 2829406 : && TREE_CODE (retval) != SSA_NAME
3062 2227643 : && !is_gimple_min_invariant (retval)
3063 7304558 : && refs_may_alias_p (retval, ref, tbaa_p))
3064 : return true;
3065 : /* If ref escapes the function then the return acts as a use. */
3066 3689787 : tree base = ao_ref_base (ref);
3067 3689787 : if (!base)
3068 : ;
3069 3689787 : else if (DECL_P (base))
3070 1337896 : return is_global_var (base);
3071 2351891 : else if (TREE_CODE (base) == MEM_REF
3072 2351891 : || TREE_CODE (base) == TARGET_MEM_REF)
3073 2351794 : return ptr_deref_may_alias_global_p (TREE_OPERAND (base, 0), false);
3074 : return false;
3075 : }
3076 :
3077 : return true;
3078 : }
3079 :
3080 : bool
3081 733759 : ref_maybe_used_by_stmt_p (gimple *stmt, tree ref, bool tbaa_p)
3082 : {
3083 733759 : ao_ref r;
3084 733759 : ao_ref_init (&r, ref);
3085 733759 : return ref_maybe_used_by_stmt_p (stmt, &r, tbaa_p);
3086 : }
3087 :
3088 : /* If the call in statement CALL may clobber the memory reference REF
3089 : return true, otherwise return false. */
3090 :
3091 : bool
3092 328860490 : call_may_clobber_ref_p_1 (gcall *call, ao_ref *ref, bool tbaa_p)
3093 : {
3094 328860490 : tree base;
3095 328860490 : tree callee;
3096 :
3097 : /* If the call is pure or const it cannot clobber anything. */
3098 328860490 : if (gimple_call_flags (call)
3099 328860490 : & (ECF_PURE|ECF_CONST|ECF_LOOPING_CONST_OR_PURE|ECF_NOVOPS))
3100 : return false;
3101 323718811 : if (gimple_call_internal_p (call))
3102 579446 : switch (auto fn = gimple_call_internal_fn (call))
3103 : {
3104 : /* Treat these internal calls like ECF_PURE for aliasing,
3105 : they don't write to any memory the program should care about.
3106 : They have important other side-effects, and read memory,
3107 : so can't be ECF_NOVOPS. */
3108 : case IFN_UBSAN_NULL:
3109 : case IFN_UBSAN_BOUNDS:
3110 : case IFN_UBSAN_VPTR:
3111 : case IFN_UBSAN_OBJECT_SIZE:
3112 : case IFN_UBSAN_PTR:
3113 : case IFN_ASAN_CHECK:
3114 : return false;
3115 7540 : case IFN_MASK_STORE:
3116 7540 : case IFN_LEN_STORE:
3117 7540 : case IFN_MASK_LEN_STORE:
3118 7540 : case IFN_MASK_STORE_LANES:
3119 7540 : case IFN_MASK_LEN_STORE_LANES:
3120 7540 : {
3121 7540 : tree rhs = gimple_call_arg (call,
3122 7540 : internal_fn_stored_value_index (fn));
3123 7540 : ao_ref lhs_ref;
3124 7540 : ao_ref_init_from_ptr_and_size (&lhs_ref, gimple_call_arg (call, 0),
3125 7540 : TYPE_SIZE_UNIT (TREE_TYPE (rhs)));
3126 : /* We cannot make this a known-size access since otherwise
3127 : we disambiguate against refs to decls that are smaller. */
3128 7540 : lhs_ref.size = -1;
3129 15080 : lhs_ref.ref_alias_set = lhs_ref.base_alias_set
3130 7540 : = tbaa_p ? get_deref_alias_set
3131 7092 : (TREE_TYPE (gimple_call_arg (call, 1))) : 0;
3132 7540 : return refs_may_alias_p_1 (ref, &lhs_ref, tbaa_p);
3133 : }
3134 : default:
3135 : break;
3136 : }
3137 :
3138 323468521 : callee = gimple_call_fndecl (call);
3139 :
3140 323468521 : if (callee != NULL_TREE && !ref->volatile_p)
3141 : {
3142 303041656 : struct cgraph_node *node = cgraph_node::get (callee);
3143 303041656 : if (node)
3144 : {
3145 302755294 : modref_summary *summary = get_modref_function_summary (node);
3146 302755294 : if (summary)
3147 : {
3148 40452241 : if (!modref_may_conflict (call, summary->stores, ref, tbaa_p)
3149 40452241 : && (!summary->writes_errno
3150 190609 : || !targetm.ref_may_alias_errno (ref)))
3151 : {
3152 4330139 : alias_stats.modref_clobber_no_alias++;
3153 4330139 : if (dump_file && (dump_flags & TDF_DETAILS))
3154 : {
3155 52 : fprintf (dump_file,
3156 : "ipa-modref: call stmt ");
3157 52 : print_gimple_stmt (dump_file, call, 0);
3158 52 : fprintf (dump_file,
3159 : "ipa-modref: call to %s does not clobber ",
3160 : node->dump_name ());
3161 52 : if (!ref->ref && ref->base)
3162 : {
3163 32 : fprintf (dump_file, "base: ");
3164 32 : print_generic_expr (dump_file, ref->base);
3165 : }
3166 20 : else if (ref->ref)
3167 : {
3168 20 : fprintf (dump_file, "ref: ");
3169 20 : print_generic_expr (dump_file, ref->ref);
3170 : }
3171 52 : fprintf (dump_file, " alias sets: %i->%i\n",
3172 : ao_ref_base_alias_set (ref),
3173 : ao_ref_alias_set (ref));
3174 : }
3175 4330139 : return false;
3176 : }
3177 36122102 : alias_stats.modref_clobber_may_alias++;
3178 : }
3179 : }
3180 : }
3181 :
3182 319138382 : base = ao_ref_base (ref);
3183 319138382 : if (!base)
3184 : return true;
3185 :
3186 319138382 : if (TREE_CODE (base) == SSA_NAME
3187 319137834 : || CONSTANT_CLASS_P (base))
3188 : return false;
3189 :
3190 : /* A call that is not without side-effects might involve volatile
3191 : accesses and thus conflicts with all other volatile accesses. */
3192 311131105 : if (ref->volatile_p)
3193 : return true;
3194 :
3195 : /* If the reference is based on a decl that is not aliased the call
3196 : cannot possibly clobber it. */
3197 309670609 : if (DECL_P (base)
3198 281381389 : && !may_be_aliased (base)
3199 : /* But local non-readonly statics can be modified through recursion
3200 : or the call may implement a threading barrier which we must
3201 : treat as may-def. */
3202 500621809 : && (TREE_READONLY (base)
3203 183488628 : || !is_global_var (base)))
3204 : return false;
3205 :
3206 : /* If the reference is based on a pointer that points to memory
3207 : that may not be written to then the call cannot possibly clobber it. */
3208 128227183 : if ((TREE_CODE (base) == MEM_REF
3209 128227183 : || TREE_CODE (base) == TARGET_MEM_REF)
3210 28289220 : && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME
3211 156145935 : && SSA_NAME_POINTS_TO_READONLY_MEMORY (TREE_OPERAND (base, 0)))
3212 : return false;
3213 :
3214 127846528 : if (int res = check_fnspec (call, ref, true))
3215 : {
3216 102813983 : if (res == 1)
3217 : return true;
3218 : }
3219 : else
3220 : return false;
3221 :
3222 : /* Check if base is a global static variable that is not written
3223 : by the function. */
3224 97257244 : if (callee != NULL_TREE && VAR_P (base) && TREE_STATIC (base))
3225 : {
3226 10287260 : struct cgraph_node *node = cgraph_node::get (callee);
3227 10287260 : bitmap written;
3228 10287260 : int id;
3229 :
3230 10287260 : if (node
3231 10286801 : && (id = ipa_reference_var_uid (base)) != -1
3232 4307833 : && (written = ipa_reference_get_written_global (node))
3233 10381218 : && !bitmap_bit_p (written, id))
3234 : return false;
3235 : }
3236 :
3237 : /* Check if the base variable is call-clobbered. */
3238 97180032 : if (DECL_P (base))
3239 76344576 : return pt_solution_includes (gimple_call_clobber_set (call), base);
3240 20835456 : else if ((TREE_CODE (base) == MEM_REF
3241 20835456 : || TREE_CODE (base) == TARGET_MEM_REF)
3242 20835456 : && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME)
3243 : {
3244 20532902 : struct ptr_info_def *pi = SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0));
3245 20532902 : if (!pi)
3246 : return true;
3247 :
3248 19746818 : return pt_solutions_intersect (gimple_call_clobber_set (call), &pi->pt);
3249 : }
3250 :
3251 : return true;
3252 : }
3253 :
3254 : /* If the call in statement CALL may clobber the memory reference REF
3255 : return true, otherwise return false. */
3256 :
3257 : bool
3258 320938 : call_may_clobber_ref_p (gcall *call, tree ref, bool tbaa_p)
3259 : {
3260 320938 : bool res;
3261 320938 : ao_ref r;
3262 320938 : ao_ref_init (&r, ref);
3263 320938 : res = call_may_clobber_ref_p_1 (call, &r, tbaa_p);
3264 320938 : if (res)
3265 45861 : ++alias_stats.call_may_clobber_ref_p_may_alias;
3266 : else
3267 275077 : ++alias_stats.call_may_clobber_ref_p_no_alias;
3268 320938 : return res;
3269 : }
3270 :
3271 :
3272 : /* If the statement STMT may clobber the memory reference REF return true,
3273 : otherwise return false. */
3274 :
3275 : bool
3276 1922252963 : stmt_may_clobber_ref_p_1 (gimple *stmt, ao_ref *ref, bool tbaa_p)
3277 : {
3278 1922252963 : if (is_gimple_call (stmt))
3279 : {
3280 334385475 : tree lhs = gimple_call_lhs (stmt);
3281 334385475 : if (lhs
3282 155292147 : && TREE_CODE (lhs) != SSA_NAME)
3283 : {
3284 59360467 : ao_ref r;
3285 59360467 : ao_ref_init (&r, lhs);
3286 59360467 : if (refs_may_alias_p_1 (ref, &r, tbaa_p))
3287 5944719 : return true;
3288 : }
3289 :
3290 328440756 : return call_may_clobber_ref_p_1 (as_a <gcall *> (stmt), ref, tbaa_p);
3291 : }
3292 1587867488 : else if (gimple_assign_single_p (stmt))
3293 : {
3294 1579678250 : tree lhs = gimple_assign_lhs (stmt);
3295 1579678250 : if (TREE_CODE (lhs) != SSA_NAME)
3296 : {
3297 1578821255 : ao_ref r;
3298 1578821255 : ao_ref_init (&r, lhs);
3299 1578821255 : return refs_may_alias_p_1 (ref, &r, tbaa_p);
3300 : }
3301 : }
3302 8189238 : else if (gimple_code (stmt) == GIMPLE_ASM)
3303 : return true;
3304 :
3305 : return false;
3306 : }
3307 :
3308 : bool
3309 4143805 : stmt_may_clobber_ref_p (gimple *stmt, tree ref, bool tbaa_p)
3310 : {
3311 4143805 : ao_ref r;
3312 4143805 : ao_ref_init (&r, ref);
3313 4143805 : return stmt_may_clobber_ref_p_1 (stmt, &r, tbaa_p);
3314 : }
3315 :
3316 : /* Return true if store1 and store2 described by corresponding tuples
3317 : <BASE, OFFSET, SIZE, MAX_SIZE> have the same size and store to the same
3318 : address. */
3319 :
3320 : static bool
3321 130877718 : same_addr_size_stores_p (tree base1, poly_int64 offset1, poly_int64 size1,
3322 : poly_int64 max_size1,
3323 : tree base2, poly_int64 offset2, poly_int64 size2,
3324 : poly_int64 max_size2)
3325 : {
3326 : /* Offsets need to be 0. */
3327 130877718 : if (maybe_ne (offset1, 0)
3328 130877718 : || maybe_ne (offset2, 0))
3329 : return false;
3330 :
3331 36200810 : bool base1_obj_p = SSA_VAR_P (base1);
3332 36200810 : bool base2_obj_p = SSA_VAR_P (base2);
3333 :
3334 : /* We need one object. */
3335 36200810 : if (base1_obj_p == base2_obj_p)
3336 : return false;
3337 4563177 : tree obj = base1_obj_p ? base1 : base2;
3338 :
3339 : /* And we need one MEM_REF. */
3340 4563177 : bool base1_memref_p = TREE_CODE (base1) == MEM_REF;
3341 4563177 : bool base2_memref_p = TREE_CODE (base2) == MEM_REF;
3342 4563177 : if (base1_memref_p == base2_memref_p)
3343 : return false;
3344 4469504 : tree memref = base1_memref_p ? base1 : base2;
3345 :
3346 : /* Sizes need to be valid. */
3347 4469504 : if (!known_size_p (max_size1)
3348 4446958 : || !known_size_p (max_size2)
3349 4446628 : || !known_size_p (size1)
3350 8916132 : || !known_size_p (size2))
3351 : return false;
3352 :
3353 : /* Max_size needs to match size. */
3354 4446628 : if (maybe_ne (max_size1, size1)
3355 4446628 : || maybe_ne (max_size2, size2))
3356 : return false;
3357 :
3358 : /* Sizes need to match. */
3359 4401496 : if (maybe_ne (size1, size2))
3360 : return false;
3361 :
3362 :
3363 : /* Check that memref is a store to pointer with singleton points-to info. */
3364 1183330 : if (!integer_zerop (TREE_OPERAND (memref, 1)))
3365 : return false;
3366 904353 : tree ptr = TREE_OPERAND (memref, 0);
3367 904353 : if (TREE_CODE (ptr) != SSA_NAME)
3368 : return false;
3369 904077 : struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr);
3370 904077 : unsigned int pt_uid;
3371 904077 : if (pi == NULL
3372 904077 : || !pt_solution_singleton_or_null_p (&pi->pt, &pt_uid))
3373 711714 : return false;
3374 :
3375 : /* Be conservative with non-call exceptions when the address might
3376 : be NULL. */
3377 192363 : if (cfun->can_throw_non_call_exceptions && pi->pt.null)
3378 : return false;
3379 :
3380 : /* Check that ptr points relative to obj. */
3381 192357 : unsigned int obj_uid = DECL_PT_UID (obj);
3382 192357 : if (obj_uid != pt_uid)
3383 : return false;
3384 :
3385 : /* Check that the object size is the same as the store size. That ensures us
3386 : that ptr points to the start of obj. */
3387 33992 : return (DECL_SIZE (obj)
3388 33992 : && poly_int_tree_p (DECL_SIZE (obj))
3389 101815 : && known_eq (wi::to_poly_offset (DECL_SIZE (obj)), size1));
3390 : }
3391 :
3392 : /* Return true if REF is killed by an store described by
3393 : BASE, OFFSET, SIZE and MAX_SIZE. */
3394 :
3395 : static bool
3396 227192447 : store_kills_ref_p (tree base, poly_int64 offset, poly_int64 size,
3397 : poly_int64 max_size, ao_ref *ref)
3398 : {
3399 227192447 : poly_int64 ref_offset = ref->offset;
3400 : /* We can get MEM[symbol: sZ, index: D.8862_1] here,
3401 : so base == ref->base does not always hold. */
3402 227192447 : if (base != ref->base)
3403 : {
3404 : /* Try using points-to info. */
3405 130877718 : if (same_addr_size_stores_p (base, offset, size, max_size, ref->base,
3406 : ref->offset, ref->size, ref->max_size))
3407 : return true;
3408 :
3409 : /* If both base and ref->base are MEM_REFs, only compare the
3410 : first operand, and if the second operand isn't equal constant,
3411 : try to add the offsets into offset and ref_offset. */
3412 34049254 : if (TREE_CODE (base) == MEM_REF && TREE_CODE (ref->base) == MEM_REF
3413 156289681 : && TREE_OPERAND (base, 0) == TREE_OPERAND (ref->base, 0))
3414 : {
3415 18896247 : if (!tree_int_cst_equal (TREE_OPERAND (base, 1),
3416 18896247 : TREE_OPERAND (ref->base, 1)))
3417 : {
3418 6772342 : poly_offset_int off1 = mem_ref_offset (base);
3419 6772342 : off1 <<= LOG2_BITS_PER_UNIT;
3420 6772342 : off1 += offset;
3421 6772342 : poly_offset_int off2 = mem_ref_offset (ref->base);
3422 6772342 : off2 <<= LOG2_BITS_PER_UNIT;
3423 6772342 : off2 += ref_offset;
3424 6772342 : if (!off1.to_shwi (&offset) || !off2.to_shwi (&ref_offset))
3425 0 : size = -1;
3426 : }
3427 : }
3428 : else
3429 111981310 : size = -1;
3430 : }
3431 : /* For a must-alias check we need to be able to constrain
3432 : the access properly. */
3433 227192286 : return (known_eq (size, max_size)
3434 227192286 : && known_subrange_p (ref_offset, ref->max_size, offset, size));
3435 : }
3436 :
3437 : /* If STMT kills the memory reference REF return true, otherwise
3438 : return false. */
3439 :
3440 : bool
3441 275563626 : stmt_kills_ref_p (gimple *stmt, ao_ref *ref)
3442 : {
3443 275563626 : if (!ao_ref_base (ref))
3444 : return false;
3445 :
3446 275563626 : if (gimple_has_lhs (stmt)
3447 240298113 : && TREE_CODE (gimple_get_lhs (stmt)) != SSA_NAME
3448 : /* The assignment is not necessarily carried out if it can throw
3449 : and we can catch it in the current function where we could inspect
3450 : the previous value. Similarly if the function can throw externally
3451 : and the ref does not die on the function return.
3452 : ??? We only need to care about the RHS throwing. For aggregate
3453 : assignments or similar calls and non-call exceptions the LHS
3454 : might throw as well.
3455 : ??? We also should care about possible longjmp, but since we
3456 : do not understand that longjmp is not using global memory we will
3457 : not consider a kill here since the function call will be considered
3458 : as possibly using REF. */
3459 234648589 : && !stmt_can_throw_internal (cfun, stmt)
3460 253169218 : && (!stmt_can_throw_external (cfun, stmt)
3461 4166432 : || !ref_may_alias_global_p (ref, false)))
3462 : {
3463 230045502 : tree lhs = gimple_get_lhs (stmt);
3464 : /* If LHS is literally a base of the access we are done. */
3465 230045502 : if (ref->ref)
3466 : {
3467 228552351 : tree base = ref->ref;
3468 228552351 : tree innermost_dropped_array_ref = NULL_TREE;
3469 228552351 : if (handled_component_p (base))
3470 : {
3471 147413830 : tree saved_lhs0 = NULL_TREE;
3472 263156134 : if (handled_component_p (lhs))
3473 : {
3474 115742304 : saved_lhs0 = TREE_OPERAND (lhs, 0);
3475 115742304 : TREE_OPERAND (lhs, 0) = integer_zero_node;
3476 : }
3477 249406936 : do
3478 : {
3479 : /* Just compare the outermost handled component, if
3480 : they are equal we have found a possible common
3481 : base. */
3482 249406936 : tree saved_base0 = TREE_OPERAND (base, 0);
3483 249406936 : TREE_OPERAND (base, 0) = integer_zero_node;
3484 249406936 : bool res = operand_equal_p (lhs, base, 0);
3485 249406936 : TREE_OPERAND (base, 0) = saved_base0;
3486 249406936 : if (res)
3487 : break;
3488 : /* Remember if we drop an array-ref that we need to
3489 : double-check not being at struct end. */
3490 234623556 : if (TREE_CODE (base) == ARRAY_REF
3491 234623556 : || TREE_CODE (base) == ARRAY_RANGE_REF)
3492 68442716 : innermost_dropped_array_ref = base;
3493 : /* Otherwise drop handled components of the access. */
3494 234623556 : base = saved_base0;
3495 : }
3496 367254006 : while (handled_component_p (base));
3497 147413830 : if (saved_lhs0)
3498 115742304 : TREE_OPERAND (lhs, 0) = saved_lhs0;
3499 : }
3500 : /* Finally check if the lhs has the same address and size as the
3501 : base candidate of the access. Watch out if we have dropped
3502 : an array-ref that might have flexible size, this means ref->ref
3503 : may be outside of the TYPE_SIZE of its base. */
3504 147413830 : if ((! innermost_dropped_array_ref
3505 67616025 : || ! array_ref_flexible_size_p (innermost_dropped_array_ref))
3506 365258506 : && (lhs == base
3507 215721826 : || (((TYPE_SIZE (TREE_TYPE (lhs))
3508 215721826 : == TYPE_SIZE (TREE_TYPE (base)))
3509 148892108 : || (TYPE_SIZE (TREE_TYPE (lhs))
3510 148892045 : && TYPE_SIZE (TREE_TYPE (base))
3511 148891888 : && operand_equal_p (TYPE_SIZE (TREE_TYPE (lhs)),
3512 148891888 : TYPE_SIZE (TREE_TYPE (base)),
3513 : 0)))
3514 66829718 : && operand_equal_p (lhs, base,
3515 : OEP_ADDRESS_OF
3516 : | OEP_MATCH_SIDE_EFFECTS))))
3517 : {
3518 2817508 : ++alias_stats.stmt_kills_ref_p_yes;
3519 8351236 : return true;
3520 : }
3521 : }
3522 :
3523 : /* Now look for non-literal equal bases with the restriction of
3524 : handling constant offset and size. */
3525 : /* For a must-alias check we need to be able to constrain
3526 : the access properly. */
3527 227227994 : if (!ref->max_size_known_p ())
3528 : {
3529 1253702 : ++alias_stats.stmt_kills_ref_p_no;
3530 1253702 : return false;
3531 : }
3532 225974292 : poly_int64 size, offset, max_size;
3533 225974292 : bool reverse;
3534 225974292 : tree base = get_ref_base_and_extent (lhs, &offset, &size, &max_size,
3535 : &reverse);
3536 225974292 : if (store_kills_ref_p (base, offset, size, max_size, ref))
3537 : {
3538 1462518 : ++alias_stats.stmt_kills_ref_p_yes;
3539 1462518 : return true;
3540 : }
3541 : }
3542 :
3543 270029898 : if (is_gimple_call (stmt))
3544 : {
3545 22210753 : tree callee = gimple_call_fndecl (stmt);
3546 22210753 : struct cgraph_node *node;
3547 22210753 : modref_summary *summary;
3548 :
3549 : /* Try to disambiguate using modref summary. Modref records a vector
3550 : of stores with known offsets relative to function parameters that must
3551 : happen every execution of function. Find if we have a matching
3552 : store and verify that function can not use the value. */
3553 22210753 : if (callee != NULL_TREE
3554 21183183 : && (node = cgraph_node::get (callee)) != NULL
3555 21143770 : && node->binds_to_current_def_p ()
3556 2049299 : && (summary = get_modref_function_summary (node)) != NULL
3557 1063191 : && summary->kills.length ()
3558 : /* Check that we can not trap while evaulating function
3559 : parameters. This check is overly conservative. */
3560 22338854 : && (!cfun->can_throw_non_call_exceptions
3561 0 : || (!stmt_can_throw_internal (cfun, stmt)
3562 0 : && (!stmt_can_throw_external (cfun, stmt)
3563 0 : || !ref_may_alias_global_p (ref, false)))))
3564 : {
3565 534971 : for (auto kill : summary->kills)
3566 : {
3567 160189 : ao_ref dref;
3568 :
3569 : /* We only can do useful compares if we know the access range
3570 : precisely. */
3571 160189 : if (!kill.get_ao_ref (as_a <gcall *> (stmt), &dref))
3572 24 : continue;
3573 160165 : if (store_kills_ref_p (ao_ref_base (&dref), dref.offset,
3574 : dref.size, dref.max_size, ref))
3575 : {
3576 : /* For store to be killed it needs to not be used
3577 : earlier. */
3578 9521 : if (ref_maybe_used_by_call_p_1 (as_a <gcall *> (stmt), ref,
3579 : true)
3580 9521 : || !dbg_cnt (ipa_mod_ref))
3581 : break;
3582 3482 : if (dump_file && (dump_flags & TDF_DETAILS))
3583 : {
3584 2 : fprintf (dump_file,
3585 : "ipa-modref: call stmt ");
3586 2 : print_gimple_stmt (dump_file, stmt, 0);
3587 2 : fprintf (dump_file,
3588 : "ipa-modref: call to %s kills ",
3589 : node->dump_name ());
3590 2 : print_generic_expr (dump_file, ref->base);
3591 2 : fprintf (dump_file, "\n");
3592 : }
3593 3482 : ++alias_stats.modref_kill_yes;
3594 3482 : return true;
3595 : }
3596 : }
3597 124619 : ++alias_stats.modref_kill_no;
3598 : }
3599 22207271 : if (callee != NULL_TREE
3600 22207271 : && gimple_call_builtin_p (stmt, BUILT_IN_NORMAL))
3601 4483399 : switch (DECL_FUNCTION_CODE (callee))
3602 : {
3603 573375 : case BUILT_IN_FREE:
3604 573375 : {
3605 573375 : tree ptr = gimple_call_arg (stmt, 0);
3606 573375 : tree base = ao_ref_base (ref);
3607 573375 : if (base && TREE_CODE (base) == MEM_REF
3608 676748 : && TREE_OPERAND (base, 0) == ptr)
3609 : {
3610 14575 : ++alias_stats.stmt_kills_ref_p_yes;
3611 14575 : return true;
3612 : }
3613 : break;
3614 : }
3615 :
3616 1436252 : case BUILT_IN_MEMCPY:
3617 1436252 : case BUILT_IN_MEMPCPY:
3618 1436252 : case BUILT_IN_MEMMOVE:
3619 1436252 : case BUILT_IN_MEMSET:
3620 1436252 : case BUILT_IN_MEMCPY_CHK:
3621 1436252 : case BUILT_IN_MEMPCPY_CHK:
3622 1436252 : case BUILT_IN_MEMMOVE_CHK:
3623 1436252 : case BUILT_IN_MEMSET_CHK:
3624 1436252 : case BUILT_IN_STRNCPY:
3625 1436252 : case BUILT_IN_STPNCPY:
3626 1436252 : case BUILT_IN_CALLOC:
3627 1436252 : {
3628 : /* For a must-alias check we need to be able to constrain
3629 : the access properly. */
3630 1436252 : if (!ref->max_size_known_p ())
3631 : {
3632 62562 : ++alias_stats.stmt_kills_ref_p_no;
3633 446170 : return false;
3634 : }
3635 1373690 : tree dest;
3636 1373690 : tree len;
3637 :
3638 : /* In execution order a calloc call will never kill
3639 : anything. However, DSE will (ab)use this interface
3640 : to ask if a calloc call writes the same memory locations
3641 : as a later assignment, memset, etc. So handle calloc
3642 : in the expected way. */
3643 1373690 : if (DECL_FUNCTION_CODE (callee) == BUILT_IN_CALLOC)
3644 : {
3645 1445 : tree arg0 = gimple_call_arg (stmt, 0);
3646 1445 : tree arg1 = gimple_call_arg (stmt, 1);
3647 1445 : if (TREE_CODE (arg0) != INTEGER_CST
3648 1300 : || TREE_CODE (arg1) != INTEGER_CST)
3649 : {
3650 177 : ++alias_stats.stmt_kills_ref_p_no;
3651 177 : return false;
3652 : }
3653 :
3654 1268 : dest = gimple_call_lhs (stmt);
3655 1268 : if (!dest)
3656 : {
3657 1 : ++alias_stats.stmt_kills_ref_p_no;
3658 1 : return false;
3659 : }
3660 1267 : len = fold_build2 (MULT_EXPR, TREE_TYPE (arg0), arg0, arg1);
3661 : }
3662 : else
3663 : {
3664 1372245 : dest = gimple_call_arg (stmt, 0);
3665 1372245 : len = gimple_call_arg (stmt, 2);
3666 : }
3667 1373512 : if (!poly_int_tree_p (len))
3668 : return false;
3669 1057990 : ao_ref dref;
3670 1057990 : ao_ref_init_from_ptr_and_size (&dref, dest, len);
3671 1057990 : if (store_kills_ref_p (ao_ref_base (&dref), dref.offset,
3672 : dref.size, dref.max_size, ref))
3673 : {
3674 5346 : ++alias_stats.stmt_kills_ref_p_yes;
3675 5346 : return true;
3676 : }
3677 1052644 : break;
3678 : }
3679 :
3680 12326 : case BUILT_IN_VA_END:
3681 12326 : {
3682 12326 : tree ptr = gimple_call_arg (stmt, 0);
3683 12326 : if (TREE_CODE (ptr) == ADDR_EXPR)
3684 : {
3685 12275 : tree base = ao_ref_base (ref);
3686 12275 : if (TREE_OPERAND (ptr, 0) == base)
3687 : {
3688 7504 : ++alias_stats.stmt_kills_ref_p_yes;
3689 7504 : return true;
3690 : }
3691 : }
3692 : break;
3693 : }
3694 :
3695 : default:;
3696 : }
3697 : }
3698 269620729 : ++alias_stats.stmt_kills_ref_p_no;
3699 269620729 : return false;
3700 : }
3701 :
3702 : bool
3703 0 : stmt_kills_ref_p (gimple *stmt, tree ref)
3704 : {
3705 0 : ao_ref r;
3706 0 : ao_ref_init (&r, ref);
3707 0 : return stmt_kills_ref_p (stmt, &r);
3708 : }
3709 :
3710 : /* Return whether REF can be subject to store data races. */
3711 :
3712 : bool
3713 25313 : ref_can_have_store_data_races (tree ref)
3714 : {
3715 : /* With -fallow-store-data-races do not care about them. */
3716 25313 : if (flag_store_data_races)
3717 : return false;
3718 :
3719 25208 : tree base = get_base_address (ref);
3720 25208 : if (auto_var_p (base)
3721 25208 : && ! may_be_aliased (base))
3722 : /* Automatic variables not aliased are not subject to
3723 : data races. */
3724 : return false;
3725 :
3726 : return true;
3727 : }
3728 :
3729 :
3730 : /* Walk the virtual use-def chain of VUSE until hitting the virtual operand
3731 : TARGET or a statement clobbering the memory reference REF in which
3732 : case false is returned. The walk starts with VUSE, one argument of PHI. */
3733 :
3734 : static bool
3735 125574270 : maybe_skip_until (gimple *phi, tree &target, basic_block target_bb,
3736 : ao_ref *ref, tree vuse, bool tbaa_p, unsigned int &limit,
3737 : bitmap *visited, bool abort_on_visited,
3738 : void *(*translate)(ao_ref *, tree, void *, translate_flags *),
3739 : bool (*is_backedge)(edge, void *),
3740 : translate_flags disambiguate_only,
3741 : void *data)
3742 : {
3743 125574270 : basic_block bb = gimple_bb (phi);
3744 :
3745 125574270 : if (!*visited)
3746 : {
3747 23849171 : *visited = BITMAP_ALLOC (NULL);
3748 23849171 : bitmap_tree_view (*visited);
3749 : }
3750 :
3751 125574270 : bitmap_set_bit (*visited, SSA_NAME_VERSION (PHI_RESULT (phi)));
3752 :
3753 : /* Walk until we hit the target. */
3754 125574270 : while (vuse != target)
3755 : {
3756 382831023 : gimple *def_stmt = SSA_NAME_DEF_STMT (vuse);
3757 : /* If we are searching for the target VUSE by walking up to
3758 : TARGET_BB dominating the original PHI we are finished once
3759 : we reach a default def or a definition in a block dominating
3760 : that block. Update TARGET and return. */
3761 382831023 : if (!target
3762 382831023 : && (gimple_nop_p (def_stmt)
3763 65256442 : || dominated_by_p (CDI_DOMINATORS,
3764 65256442 : target_bb, gimple_bb (def_stmt))))
3765 : {
3766 18400595 : target = vuse;
3767 18400595 : return true;
3768 : }
3769 :
3770 : /* Recurse for PHI nodes. */
3771 364430428 : if (gphi *phi = dyn_cast <gphi *> (def_stmt))
3772 : {
3773 : /* An already visited PHI node ends the walk successfully. */
3774 71218140 : if (bitmap_bit_p (*visited, SSA_NAME_VERSION (PHI_RESULT (phi))))
3775 34099769 : return !abort_on_visited;
3776 37118371 : vuse = get_continuation_for_phi (phi, ref, tbaa_p, limit,
3777 : visited, abort_on_visited,
3778 : translate, data, is_backedge,
3779 : disambiguate_only);
3780 37118371 : if (!vuse)
3781 : return false;
3782 32802460 : continue;
3783 : }
3784 293212288 : else if (gimple_nop_p (def_stmt))
3785 : return false;
3786 : else
3787 : {
3788 : /* A clobbering statement or the end of the IL ends it failing. */
3789 293212288 : if ((int)limit <= 0)
3790 : return false;
3791 293179457 : --limit;
3792 293179457 : if (stmt_may_clobber_ref_p_1 (def_stmt, ref, tbaa_p))
3793 : {
3794 18604605 : translate_flags tf = disambiguate_only;
3795 18604605 : if (translate
3796 18604605 : && (*translate) (ref, vuse, data, &tf) == NULL)
3797 : ;
3798 : else
3799 15315705 : return false;
3800 : }
3801 : }
3802 : /* If we reach a new basic-block see if we already skipped it
3803 : in a previous walk that ended successfully. */
3804 277863752 : if (gimple_bb (def_stmt) != bb)
3805 : {
3806 124582746 : if (!bitmap_set_bit (*visited, SSA_NAME_VERSION (vuse)))
3807 9911352 : return !abort_on_visited;
3808 114671394 : bb = gimple_bb (def_stmt);
3809 : }
3810 694281530 : vuse = gimple_vuse (def_stmt);
3811 : }
3812 : return true;
3813 : }
3814 :
3815 :
3816 : /* Starting from a PHI node for the virtual operand of the memory reference
3817 : REF find a continuation virtual operand that allows to continue walking
3818 : statements dominating PHI skipping only statements that cannot possibly
3819 : clobber REF. Decrements LIMIT for each alias disambiguation done
3820 : and aborts the walk, returning NULL_TREE if it reaches zero.
3821 : Returns NULL_TREE if no suitable virtual operand can be found. */
3822 :
3823 : tree
3824 97986397 : get_continuation_for_phi (gphi *phi, ao_ref *ref, bool tbaa_p,
3825 : unsigned int &limit, bitmap *visited,
3826 : bool abort_on_visited,
3827 : void *(*translate)(ao_ref *, tree, void *,
3828 : translate_flags *),
3829 : void *data,
3830 : bool (*is_backedge)(edge, void *),
3831 : translate_flags disambiguate_only)
3832 : {
3833 97986397 : unsigned nargs = gimple_phi_num_args (phi);
3834 :
3835 : /* Through a single-argument PHI we can simply look through. */
3836 97986397 : if (nargs == 1)
3837 3065519 : return PHI_ARG_DEF (phi, 0);
3838 :
3839 : /* For two or more arguments try to pairwise skip non-aliasing code
3840 : until we hit the phi argument definition that dominates the other one. */
3841 94920878 : basic_block phi_bb = gimple_bb (phi);
3842 94920878 : tree arg0, arg1;
3843 94920878 : unsigned i;
3844 :
3845 : /* Find a candidate for the virtual operand which definition
3846 : dominates those of all others. */
3847 : /* First look if any of the args themselves satisfy this. */
3848 174489464 : for (i = 0; i < nargs; ++i)
3849 : {
3850 151835313 : arg0 = PHI_ARG_DEF (phi, i);
3851 151835313 : if (SSA_NAME_IS_DEFAULT_DEF (arg0))
3852 : break;
3853 148664692 : basic_block def_bb = gimple_bb (SSA_NAME_DEF_STMT (arg0));
3854 148664692 : if (def_bb != phi_bb
3855 148664692 : && dominated_by_p (CDI_DOMINATORS, phi_bb, def_bb))
3856 : break;
3857 79568586 : arg0 = NULL_TREE;
3858 : }
3859 : /* If not, look if we can reach such candidate by walking defs
3860 : until we hit the immediate dominator. maybe_skip_until will
3861 : do that for us. */
3862 94920878 : basic_block dom = get_immediate_dominator (CDI_DOMINATORS, phi_bb);
3863 :
3864 : /* Then check against the (to be) found candidate. */
3865 367709401 : for (i = 0; i < nargs; ++i)
3866 : {
3867 197653508 : arg1 = PHI_ARG_DEF (phi, i);
3868 197653508 : if (arg1 == arg0)
3869 : ;
3870 251148540 : else if (! maybe_skip_until (phi, arg0, dom, ref, arg1, tbaa_p,
3871 : limit, visited,
3872 : abort_on_visited,
3873 : translate, is_backedge,
3874 : /* Do not valueize when walking over
3875 : backedges. */
3876 : (is_backedge
3877 116761154 : && !is_backedge
3878 116761154 : (gimple_phi_arg_edge (phi, i), data))
3879 : ? disambiguate_only : TR_DISAMBIGUATE,
3880 : data))
3881 : return NULL_TREE;
3882 : }
3883 :
3884 75135015 : return arg0;
3885 : }
3886 :
3887 : /* Based on the memory reference REF and its virtual use VUSE call
3888 : WALKER for each virtual use that is equivalent to VUSE, including VUSE
3889 : itself. That is, for each virtual use for which its defining statement
3890 : does not clobber REF.
3891 :
3892 : WALKER is called with REF, the current virtual use and DATA. If
3893 : WALKER returns non-NULL the walk stops and its result is returned.
3894 : At the end of a non-successful walk NULL is returned.
3895 :
3896 : TRANSLATE if non-NULL is called with a pointer to REF, the virtual
3897 : use which definition is a statement that may clobber REF and DATA.
3898 : If TRANSLATE returns (void *)-1 the walk stops and NULL is returned.
3899 : If TRANSLATE returns non-NULL the walk stops and its result is returned.
3900 : If TRANSLATE returns NULL the walk continues and TRANSLATE is supposed
3901 : to adjust REF and *DATA to make that valid.
3902 :
3903 : VALUEIZE if non-NULL is called with the next VUSE that is considered
3904 : and return value is substituted for that. This can be used to
3905 : implement optimistic value-numbering for example. Note that the
3906 : VUSE argument is assumed to be valueized already.
3907 :
3908 : LIMIT specifies the number of alias queries we are allowed to do,
3909 : the walk stops when it reaches zero and NULL is returned. LIMIT
3910 : is decremented by the number of alias queries (plus adjustments
3911 : done by the callbacks) upon return.
3912 :
3913 : TODO: Cache the vector of equivalent vuses per ref, vuse pair. */
3914 :
3915 : void *
3916 67726776 : walk_non_aliased_vuses (ao_ref *ref, tree vuse, bool tbaa_p,
3917 : void *(*walker)(ao_ref *, tree, void *),
3918 : void *(*translate)(ao_ref *, tree, void *,
3919 : translate_flags *),
3920 : bool (*is_backedge)(edge, void *),
3921 : tree (*valueize)(tree),
3922 : unsigned &limit, void *data)
3923 : {
3924 67726776 : bitmap visited = NULL;
3925 67726776 : void *res;
3926 67726776 : bool translated = false;
3927 :
3928 67726776 : timevar_push (TV_ALIAS_STMT_WALK);
3929 :
3930 1076989699 : do
3931 : {
3932 1076989699 : gimple *def_stmt;
3933 :
3934 : /* ??? Do we want to account this to TV_ALIAS_STMT_WALK? */
3935 1076989699 : res = (*walker) (ref, vuse, data);
3936 : /* Abort walk. */
3937 1076989699 : if (res == (void *)-1)
3938 : {
3939 : res = NULL;
3940 : break;
3941 : }
3942 : /* Lookup succeeded. */
3943 1076989515 : else if (res != NULL)
3944 : break;
3945 :
3946 1068704217 : if (valueize)
3947 : {
3948 1050347465 : vuse = valueize (vuse);
3949 1050347465 : if (!vuse)
3950 : {
3951 : res = NULL;
3952 : break;
3953 : }
3954 : }
3955 1053007556 : def_stmt = SSA_NAME_DEF_STMT (vuse);
3956 1053007556 : if (gimple_nop_p (def_stmt))
3957 : break;
3958 1050453519 : else if (gphi *phi = dyn_cast <gphi *> (def_stmt))
3959 57913099 : vuse = get_continuation_for_phi (phi, ref, tbaa_p, limit,
3960 : &visited, translated, translate, data,
3961 : is_backedge);
3962 : else
3963 : {
3964 992540420 : if ((int)limit <= 0)
3965 : {
3966 : res = NULL;
3967 : break;
3968 : }
3969 992301472 : --limit;
3970 992301472 : if (stmt_may_clobber_ref_p_1 (def_stmt, ref, tbaa_p))
3971 : {
3972 32269759 : if (!translate)
3973 : break;
3974 27034163 : translate_flags disambiguate_only = TR_TRANSLATE;
3975 27034163 : res = (*translate) (ref, vuse, data, &disambiguate_only);
3976 : /* Failed lookup and translation. */
3977 27034163 : if (res == (void *)-1)
3978 : {
3979 : res = NULL;
3980 : break;
3981 : }
3982 : /* Lookup succeeded. */
3983 6161159 : else if (res != NULL)
3984 : break;
3985 : /* Translation succeeded, continue walking. */
3986 8063929 : translated = translated || disambiguate_only == TR_TRANSLATE;
3987 : }
3988 965025545 : vuse = gimple_vuse (def_stmt);
3989 : }
3990 : }
3991 1022938644 : while (vuse);
3992 :
3993 67726776 : if (visited)
3994 21421204 : BITMAP_FREE (visited);
3995 :
3996 67726776 : timevar_pop (TV_ALIAS_STMT_WALK);
3997 :
3998 67726776 : return res;
3999 : }
4000 :
4001 :
4002 : /* Based on the memory reference REF call WALKER for each vdef whose
4003 : defining statement may clobber REF, starting with VDEF. If REF
4004 : is NULL_TREE, each defining statement is visited.
4005 :
4006 : WALKER is called with REF, the current vdef and DATA. If WALKER
4007 : returns true the walk is stopped, otherwise it continues.
4008 :
4009 : If function entry is reached, FUNCTION_ENTRY_REACHED is set to true.
4010 : The pointer may be NULL and then we do not track this information.
4011 :
4012 : At PHI nodes walk_aliased_vdefs forks into one walk for each
4013 : PHI argument (but only one walk continues at merge points), the
4014 : return value is true if any of the walks was successful.
4015 :
4016 : The function returns the number of statements walked or -1 if
4017 : LIMIT stmts were walked and the walk was aborted at this point.
4018 : If LIMIT is zero the walk is not aborted. */
4019 :
4020 : static int
4021 291843566 : walk_aliased_vdefs_1 (ao_ref *ref, tree vdef,
4022 : bool (*walker)(ao_ref *, tree, void *), void *data,
4023 : bitmap *visited, unsigned int cnt,
4024 : bool *function_entry_reached, unsigned limit)
4025 : {
4026 911766460 : do
4027 : {
4028 1823532920 : gimple *def_stmt = SSA_NAME_DEF_STMT (vdef);
4029 :
4030 911766460 : if (*visited
4031 911766460 : && !bitmap_set_bit (*visited, SSA_NAME_VERSION (vdef)))
4032 162927080 : return cnt;
4033 :
4034 748839380 : if (gimple_nop_p (def_stmt))
4035 : {
4036 24288321 : if (function_entry_reached)
4037 3848861 : *function_entry_reached = true;
4038 24288321 : return cnt;
4039 : }
4040 724551059 : else if (gimple_code (def_stmt) == GIMPLE_PHI)
4041 : {
4042 89361808 : unsigned i;
4043 89361808 : if (!*visited)
4044 : {
4045 8100969 : *visited = BITMAP_ALLOC (NULL);
4046 8100969 : bitmap_tree_view (*visited);
4047 : }
4048 279752147 : for (i = 0; i < gimple_phi_num_args (def_stmt); ++i)
4049 : {
4050 195450807 : int res = walk_aliased_vdefs_1 (ref,
4051 : gimple_phi_arg_def (def_stmt, i),
4052 : walker, data, visited, cnt,
4053 : function_entry_reached, limit);
4054 195450807 : if (res == -1)
4055 : return -1;
4056 190390339 : cnt = res;
4057 : }
4058 84301340 : return cnt;
4059 : }
4060 :
4061 : /* ??? Do we want to account this to TV_ALIAS_STMT_WALK? */
4062 635189251 : cnt++;
4063 635189251 : if (cnt == limit)
4064 : return -1;
4065 635049998 : if ((!ref
4066 561177647 : || stmt_may_clobber_ref_p_1 (def_stmt, ref))
4067 708534272 : && (*walker) (ref, vdef, data))
4068 15127104 : return cnt;
4069 :
4070 1531689354 : vdef = gimple_vuse (def_stmt);
4071 : }
4072 : while (1);
4073 : }
4074 :
4075 : int
4076 96392759 : walk_aliased_vdefs (ao_ref *ref, tree vdef,
4077 : bool (*walker)(ao_ref *, tree, void *), void *data,
4078 : bitmap *visited,
4079 : bool *function_entry_reached, unsigned int limit)
4080 : {
4081 96392759 : bitmap local_visited = NULL;
4082 96392759 : int ret;
4083 :
4084 96392759 : timevar_push (TV_ALIAS_STMT_WALK);
4085 :
4086 96392759 : if (function_entry_reached)
4087 4820920 : *function_entry_reached = false;
4088 :
4089 166413708 : ret = walk_aliased_vdefs_1 (ref, vdef, walker, data,
4090 : visited ? visited : &local_visited, 0,
4091 : function_entry_reached, limit);
4092 96392759 : if (local_visited)
4093 8100969 : BITMAP_FREE (local_visited);
4094 :
4095 96392759 : timevar_pop (TV_ALIAS_STMT_WALK);
4096 :
4097 96392759 : return ret;
4098 : }
4099 :
4100 : /* Verify validity of the fnspec string.
4101 : See attr-fnspec.h for details. */
4102 :
4103 : void
4104 446415434 : attr_fnspec::verify ()
4105 : {
4106 446415434 : bool err = false;
4107 446415434 : if (!len)
4108 : return;
4109 :
4110 : /* Check return value specifier. */
4111 144941438 : if (len < return_desc_size)
4112 : err = true;
4113 144941438 : else if ((len - return_desc_size) % arg_desc_size)
4114 : err = true;
4115 144941438 : else if ((str[0] < '1' || str[0] > '4')
4116 144941438 : && str[0] != '.' && str[0] != 'm')
4117 0 : err = true;
4118 :
4119 144941438 : switch (str[1])
4120 : {
4121 : case ' ':
4122 : case 'p':
4123 : case 'P':
4124 : case 'c':
4125 : case 'C':
4126 : break;
4127 : default:
4128 : err = true;
4129 : }
4130 144941438 : if (err)
4131 0 : internal_error ("invalid fn spec attribute \"%s\"", str);
4132 :
4133 : /* Now check all parameters. */
4134 430896695 : for (unsigned int i = 0; arg_specified_p (i); i++)
4135 : {
4136 285955257 : unsigned int idx = arg_idx (i);
4137 285955257 : switch (str[idx])
4138 : {
4139 265488148 : case 'x':
4140 265488148 : case 'X':
4141 265488148 : case 'r':
4142 265488148 : case 'R':
4143 265488148 : case 'o':
4144 265488148 : case 'O':
4145 265488148 : case 'w':
4146 265488148 : case 'W':
4147 265488148 : case '.':
4148 265488148 : if ((str[idx + 1] >= '1' && str[idx + 1] <= '9')
4149 265488148 : || str[idx + 1] == 't')
4150 : {
4151 43183427 : if (str[idx] != 'r' && str[idx] != 'R'
4152 : && str[idx] != 'w' && str[idx] != 'W'
4153 : && str[idx] != 'o' && str[idx] != 'O')
4154 43183427 : err = true;
4155 43183427 : if (str[idx + 1] != 't'
4156 : /* Size specified is scalar, so it should be described
4157 : by ". " if specified at all. */
4158 43183427 : && (arg_specified_p (str[idx + 1] - '1')
4159 0 : && str[arg_idx (str[idx + 1] - '1')] != '.'))
4160 : err = true;
4161 : }
4162 222304721 : else if (str[idx + 1] != ' ')
4163 : err = true;
4164 : break;
4165 20467109 : default:
4166 20467109 : if (str[idx] < '1' || str[idx] > '9')
4167 : err = true;
4168 : }
4169 285955257 : if (err)
4170 0 : internal_error ("invalid fn spec attribute \"%s\" arg %i", str, i);
4171 : }
4172 : }
4173 :
4174 : /* Return true if TYPE1 and TYPE2 will always give the same answer
4175 : when compared with other types using same_type_for_tbaa. */
4176 :
4177 : static bool
4178 21549906 : types_equal_for_same_type_for_tbaa_p (tree type1, tree type2,
4179 : bool lto_streaming_safe)
4180 : {
4181 : /* We use same_type_for_tbaa_p to match types in the access path.
4182 : This check is overly conservative. */
4183 21549906 : type1 = TYPE_MAIN_VARIANT (type1);
4184 21549906 : type2 = TYPE_MAIN_VARIANT (type2);
4185 :
4186 21549906 : if (TYPE_STRUCTURAL_EQUALITY_P (type1)
4187 21549906 : != TYPE_STRUCTURAL_EQUALITY_P (type2))
4188 : return false;
4189 21271367 : if (TYPE_STRUCTURAL_EQUALITY_P (type1))
4190 : return true;
4191 :
4192 17532761 : if (lto_streaming_safe)
4193 84098 : return type1 == type2;
4194 : else
4195 17448663 : return TYPE_CANONICAL (type1) == TYPE_CANONICAL (type2);
4196 : }
4197 :
4198 : /* Return true if TYPE1 and TYPE2 will always give the same answer
4199 : when compared with other types using same_type_for_tbaa. */
4200 :
4201 : bool
4202 21258407 : types_equal_for_same_type_for_tbaa_p (tree type1, tree type2)
4203 : {
4204 21258407 : return types_equal_for_same_type_for_tbaa_p (type1, type2,
4205 21258407 : lto_streaming_expected_p ());
4206 : }
4207 :
4208 : /* Compare REF1 and REF2 and return flags specifying their differences.
4209 : If LTO_STREAMING_SAFE is true do not use alias sets and canonical
4210 : types that are going to be recomputed.
4211 : If TBAA is true also compare TBAA metadata. */
4212 :
4213 : int
4214 171558 : ao_compare::compare_ao_refs (ao_ref *ref1, ao_ref *ref2,
4215 : bool lto_streaming_safe,
4216 : bool tbaa)
4217 : {
4218 171558 : if (TREE_THIS_VOLATILE (ref1->ref) != TREE_THIS_VOLATILE (ref2->ref))
4219 : return SEMANTICS;
4220 171546 : tree base1 = ao_ref_base (ref1);
4221 171546 : tree base2 = ao_ref_base (ref2);
4222 :
4223 171546 : if (!known_eq (ref1->offset, ref2->offset)
4224 171546 : || !known_eq (ref1->size, ref2->size)
4225 343092 : || !known_eq (ref1->max_size, ref2->max_size))
4226 : return SEMANTICS;
4227 :
4228 : /* For variable accesses we need to compare actual paths
4229 : to check that both refs are accessing same address and the access size. */
4230 171543 : if (!known_eq (ref1->size, ref1->max_size))
4231 : {
4232 3800 : if (!operand_equal_p (TYPE_SIZE (TREE_TYPE (ref1->ref)),
4233 3800 : TYPE_SIZE (TREE_TYPE (ref2->ref)), 0))
4234 : return SEMANTICS;
4235 3800 : tree r1 = ref1->ref;
4236 3800 : tree r2 = ref2->ref;
4237 :
4238 : /* Handle toplevel COMPONENT_REFs of bitfields.
4239 : Those are special since they are not allowed in
4240 : ADDR_EXPR. */
4241 3800 : if (TREE_CODE (r1) == COMPONENT_REF
4242 3800 : && DECL_BIT_FIELD (TREE_OPERAND (r1, 1)))
4243 : {
4244 0 : if (TREE_CODE (r2) != COMPONENT_REF
4245 0 : || !DECL_BIT_FIELD (TREE_OPERAND (r2, 1)))
4246 : return SEMANTICS;
4247 0 : tree field1 = TREE_OPERAND (r1, 1);
4248 0 : tree field2 = TREE_OPERAND (r2, 1);
4249 0 : if (!operand_equal_p (DECL_FIELD_OFFSET (field1),
4250 0 : DECL_FIELD_OFFSET (field2), 0)
4251 0 : || !operand_equal_p (DECL_FIELD_BIT_OFFSET (field1),
4252 0 : DECL_FIELD_BIT_OFFSET (field2), 0)
4253 0 : || !operand_equal_p (DECL_SIZE (field1), DECL_SIZE (field2), 0)
4254 0 : || !types_compatible_p (TREE_TYPE (r1),
4255 0 : TREE_TYPE (r2)))
4256 0 : return SEMANTICS;
4257 0 : r1 = TREE_OPERAND (r1, 0);
4258 0 : r2 = TREE_OPERAND (r2, 0);
4259 : }
4260 3800 : else if (TREE_CODE (r2) == COMPONENT_REF
4261 3800 : && DECL_BIT_FIELD (TREE_OPERAND (r2, 1)))
4262 : return SEMANTICS;
4263 :
4264 : /* Similarly for bit field refs. */
4265 3800 : if (TREE_CODE (r1) == BIT_FIELD_REF)
4266 : {
4267 0 : if (TREE_CODE (r2) != BIT_FIELD_REF
4268 0 : || !operand_equal_p (TREE_OPERAND (r1, 1),
4269 0 : TREE_OPERAND (r2, 1), 0)
4270 0 : || !operand_equal_p (TREE_OPERAND (r1, 2),
4271 0 : TREE_OPERAND (r2, 2), 0)
4272 0 : || !types_compatible_p (TREE_TYPE (r1),
4273 0 : TREE_TYPE (r2)))
4274 0 : return SEMANTICS;
4275 0 : r1 = TREE_OPERAND (r1, 0);
4276 0 : r2 = TREE_OPERAND (r2, 0);
4277 : }
4278 3800 : else if (TREE_CODE (r2) == BIT_FIELD_REF)
4279 : return SEMANTICS;
4280 :
4281 : /* Now we can compare the address of actual memory access. */
4282 3800 : if (!operand_equal_p (r1, r2, OEP_ADDRESS_OF | OEP_MATCH_SIDE_EFFECTS))
4283 : return SEMANTICS;
4284 : }
4285 : /* For constant accesses we get more matches by comparing offset only. */
4286 167743 : else if (!operand_equal_p (base1, base2,
4287 : OEP_ADDRESS_OF | OEP_MATCH_SIDE_EFFECTS))
4288 : return SEMANTICS;
4289 :
4290 : /* We can't simply use get_object_alignment_1 on the full
4291 : reference as for accesses with variable indexes this reports
4292 : too conservative alignment. */
4293 171343 : unsigned int align1, align2;
4294 171343 : unsigned HOST_WIDE_INT bitpos1, bitpos2;
4295 171343 : bool known1 = get_object_alignment_1 (base1, &align1, &bitpos1);
4296 171343 : bool known2 = get_object_alignment_1 (base2, &align2, &bitpos2);
4297 : /* ??? For MEMREF get_object_alignment_1 determines aligned from
4298 : TYPE_ALIGN but still returns false. This seem to contradict
4299 : its description. So compare even if alignment is unknown. */
4300 171343 : if (known1 != known2
4301 171343 : || (bitpos1 != bitpos2 || align1 != align2))
4302 : return SEMANTICS;
4303 :
4304 : /* Now we know that accesses are semantically same. */
4305 171128 : int flags = 0;
4306 :
4307 : /* ao_ref_base strips inner MEM_REF [&decl], recover from that here. */
4308 171128 : tree rbase1 = ref1->ref;
4309 171128 : if (rbase1)
4310 298991 : while (handled_component_p (rbase1))
4311 127863 : rbase1 = TREE_OPERAND (rbase1, 0);
4312 171128 : tree rbase2 = ref2->ref;
4313 298967 : while (handled_component_p (rbase2))
4314 127839 : rbase2 = TREE_OPERAND (rbase2, 0);
4315 :
4316 : /* MEM_REFs and TARGET_MEM_REFs record dependence cliques which are used to
4317 : implement restrict pointers. MR_DEPENDENCE_CLIQUE 0 means no information.
4318 : Otherwise we need to match bases and cliques. */
4319 171128 : if ((((TREE_CODE (rbase1) == MEM_REF || TREE_CODE (rbase1) == TARGET_MEM_REF)
4320 100980 : && MR_DEPENDENCE_CLIQUE (rbase1))
4321 143184 : || ((TREE_CODE (rbase2) == MEM_REF || TREE_CODE (rbase2) == TARGET_MEM_REF)
4322 73036 : && MR_DEPENDENCE_CLIQUE (rbase2)))
4323 199072 : && (TREE_CODE (rbase1) != TREE_CODE (rbase2)
4324 27944 : || MR_DEPENDENCE_CLIQUE (rbase1) != MR_DEPENDENCE_CLIQUE (rbase2)
4325 27863 : || (MR_DEPENDENCE_BASE (rbase1) != MR_DEPENDENCE_BASE (rbase2))))
4326 : flags |= DEPENDENCE_CLIQUE;
4327 :
4328 171128 : if (!tbaa)
4329 : return flags;
4330 :
4331 : /* Alias sets are not stable across LTO sreaming; be conservative here
4332 : and compare types the alias sets are ultimately based on. */
4333 171099 : if (lto_streaming_safe)
4334 : {
4335 2851 : tree t1 = ao_ref_alias_ptr_type (ref1);
4336 2851 : tree t2 = ao_ref_alias_ptr_type (ref2);
4337 2851 : if (!alias_ptr_types_compatible_p (t1, t2))
4338 13 : flags |= REF_ALIAS_SET;
4339 :
4340 2851 : t1 = ao_ref_base_alias_ptr_type (ref1);
4341 2851 : t2 = ao_ref_base_alias_ptr_type (ref2);
4342 2851 : if (!alias_ptr_types_compatible_p (t1, t2))
4343 22 : flags |= BASE_ALIAS_SET;
4344 : }
4345 : else
4346 : {
4347 168248 : if (ao_ref_alias_set (ref1) != ao_ref_alias_set (ref2))
4348 0 : flags |= REF_ALIAS_SET;
4349 168248 : if (ao_ref_base_alias_set (ref1) != ao_ref_base_alias_set (ref2))
4350 0 : flags |= BASE_ALIAS_SET;
4351 : }
4352 :
4353 : /* Access path is used only on non-view-converted references. */
4354 171099 : bool view_converted = view_converted_memref_p (rbase1);
4355 171099 : if (view_converted_memref_p (rbase2) != view_converted)
4356 0 : return flags | ACCESS_PATH;
4357 171099 : else if (view_converted)
4358 : return flags;
4359 :
4360 :
4361 : /* Find start of access paths and look for trailing arrays. */
4362 165966 : tree c1 = ref1->ref, c2 = ref2->ref;
4363 165966 : tree end_struct_ref1 = NULL, end_struct_ref2 = NULL;
4364 165966 : int nskipped1 = 0, nskipped2 = 0;
4365 165966 : int i = 0;
4366 :
4367 293715 : for (tree p1 = ref1->ref; handled_component_p (p1); p1 = TREE_OPERAND (p1, 0))
4368 : {
4369 127749 : if (component_ref_to_zero_sized_trailing_array_p (p1))
4370 133 : end_struct_ref1 = p1;
4371 127749 : if (ends_tbaa_access_path_p (p1))
4372 5639 : c1 = p1, nskipped1 = i;
4373 127749 : i++;
4374 : }
4375 165966 : i = 0;
4376 293691 : for (tree p2 = ref2->ref; handled_component_p (p2); p2 = TREE_OPERAND (p2, 0))
4377 : {
4378 127725 : if (component_ref_to_zero_sized_trailing_array_p (p2))
4379 140 : end_struct_ref2 = p2;
4380 127725 : if (ends_tbaa_access_path_p (p2))
4381 5639 : c2 = p2, nskipped2 = i;
4382 127725 : i++;
4383 : }
4384 :
4385 : /* For variable accesses we can not rely on offset match below.
4386 : We know that paths are struturally same, so only check that
4387 : starts of TBAA paths did not diverge. */
4388 165966 : if (!known_eq (ref1->size, ref1->max_size)
4389 165966 : && nskipped1 != nskipped2)
4390 0 : return flags | ACCESS_PATH;
4391 :
4392 : /* Information about trailing refs is used by
4393 : aliasing_component_refs_p that is applied only if paths
4394 : has handled components.. */
4395 165966 : if (!handled_component_p (c1) && !handled_component_p (c2))
4396 : ;
4397 72442 : else if ((end_struct_ref1 != NULL) != (end_struct_ref2 != NULL))
4398 27 : return flags | ACCESS_PATH;
4399 165939 : if (end_struct_ref1
4400 166062 : && same_type_for_tbaa (TREE_TYPE (end_struct_ref1),
4401 123 : TREE_TYPE (end_struct_ref2)) != 1)
4402 3 : return flags | ACCESS_PATH;
4403 :
4404 : /* Now compare all handled components of the access path.
4405 : We have three oracles that cares about access paths:
4406 : - aliasing_component_refs_p
4407 : - nonoverlapping_refs_since_match_p
4408 : - nonoverlapping_component_refs_p
4409 : We need to match things these oracles compare.
4410 :
4411 : It is only necessary to check types for compatibility
4412 : and offsets. Rest of what oracles compares are actual
4413 : addresses. Those are already known to be same:
4414 : - for constant accesses we check offsets
4415 : - for variable accesses we already matched
4416 : the path lexically with operand_equal_p. */
4417 417086 : while (true)
4418 : {
4419 291511 : bool comp1 = handled_component_p (c1);
4420 291511 : bool comp2 = handled_component_p (c2);
4421 :
4422 291511 : if (comp1 != comp2)
4423 12 : return flags | ACCESS_PATH;
4424 291499 : if (!comp1)
4425 : break;
4426 :
4427 125698 : if (TREE_CODE (c1) != TREE_CODE (c2))
4428 0 : return flags | ACCESS_PATH;
4429 :
4430 : /* aliasing_component_refs_p attempts to find type match within
4431 : the paths. For that reason both types needs to be equal
4432 : with respect to same_type_for_tbaa_p. */
4433 125698 : if (!types_equal_for_same_type_for_tbaa_p (TREE_TYPE (c1),
4434 125698 : TREE_TYPE (c2),
4435 : lto_streaming_safe))
4436 123 : return flags | ACCESS_PATH;
4437 251150 : if (component_ref_to_zero_sized_trailing_array_p (c1)
4438 125575 : != component_ref_to_zero_sized_trailing_array_p (c2))
4439 0 : return flags | ACCESS_PATH;
4440 :
4441 : /* aliasing_matching_component_refs_p compares
4442 : offsets within the path. Other properties are ignored.
4443 : Do not bother to verify offsets in variable accesses. Here we
4444 : already compared them by operand_equal_p so they are
4445 : structurally same. */
4446 125575 : if (!known_eq (ref1->size, ref1->max_size))
4447 : {
4448 4558 : poly_int64 offadj1, sztmc1, msztmc1;
4449 4558 : bool reverse1;
4450 4558 : get_ref_base_and_extent (c1, &offadj1, &sztmc1, &msztmc1, &reverse1);
4451 4558 : poly_int64 offadj2, sztmc2, msztmc2;
4452 4558 : bool reverse2;
4453 4558 : get_ref_base_and_extent (c2, &offadj2, &sztmc2, &msztmc2, &reverse2);
4454 4558 : if (!known_eq (offadj1, offadj2))
4455 0 : return flags | ACCESS_PATH;
4456 : }
4457 125575 : c1 = TREE_OPERAND (c1, 0);
4458 125575 : c2 = TREE_OPERAND (c2, 0);
4459 125575 : }
4460 : /* Finally test the access type. */
4461 165801 : if (!types_equal_for_same_type_for_tbaa_p (TREE_TYPE (c1),
4462 165801 : TREE_TYPE (c2),
4463 : lto_streaming_safe))
4464 1567 : return flags | ACCESS_PATH;
4465 : return flags;
4466 : }
4467 :
4468 : /* Hash REF to HSTATE. If LTO_STREAMING_SAFE do not use alias sets
4469 : and canonical types. */
4470 : void
4471 7954601 : ao_compare::hash_ao_ref (ao_ref *ref, bool lto_streaming_safe, bool tbaa,
4472 : inchash::hash &hstate)
4473 : {
4474 7954601 : tree base = ao_ref_base (ref);
4475 7954601 : tree tbase = base;
4476 :
4477 7954601 : if (!known_eq (ref->size, ref->max_size))
4478 : {
4479 418451 : tree r = ref->ref;
4480 418451 : if (TREE_CODE (r) == COMPONENT_REF
4481 418451 : && DECL_BIT_FIELD (TREE_OPERAND (r, 1)))
4482 : {
4483 1713 : tree field = TREE_OPERAND (r, 1);
4484 1713 : hash_operand (DECL_FIELD_OFFSET (field), hstate, 0);
4485 1713 : hash_operand (DECL_FIELD_BIT_OFFSET (field), hstate, 0);
4486 1713 : hash_operand (DECL_SIZE (field), hstate, 0);
4487 1713 : r = TREE_OPERAND (r, 0);
4488 : }
4489 418451 : if (TREE_CODE (r) == BIT_FIELD_REF)
4490 : {
4491 1704 : hash_operand (TREE_OPERAND (r, 1), hstate, 0);
4492 1704 : hash_operand (TREE_OPERAND (r, 2), hstate, 0);
4493 1704 : r = TREE_OPERAND (r, 0);
4494 : }
4495 418451 : hash_operand (TYPE_SIZE (TREE_TYPE (ref->ref)), hstate, 0);
4496 418451 : hash_operand (r, hstate, OEP_ADDRESS_OF | OEP_MATCH_SIDE_EFFECTS);
4497 : }
4498 : else
4499 : {
4500 7536150 : hash_operand (tbase, hstate, OEP_ADDRESS_OF | OEP_MATCH_SIDE_EFFECTS);
4501 7536150 : hstate.add_poly_int (ref->offset);
4502 7536150 : hstate.add_poly_int (ref->size);
4503 7536150 : hstate.add_poly_int (ref->max_size);
4504 : }
4505 7954601 : if (!lto_streaming_safe && tbaa)
4506 : {
4507 7636154 : hstate.add_int (ao_ref_alias_set (ref));
4508 7636154 : hstate.add_int (ao_ref_base_alias_set (ref));
4509 : }
4510 7954601 : }
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