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910fdc79 | 1 | /* Tree based points-to analysis |
66647d44 | 2 | Copyright (C) 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. |
910fdc79 DB |
3 | Contributed by Daniel Berlin <dberlin@dberlin.org> |
4 | ||
9dcd6f09 | 5 | This file is part of GCC. |
910fdc79 | 6 | |
9dcd6f09 NC |
7 | GCC is free software; you can redistribute it and/or modify |
8 | under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 3 of the License, or | |
10 | (at your option) any later version. | |
910fdc79 | 11 | |
9dcd6f09 NC |
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. | |
910fdc79 | 16 | |
9dcd6f09 NC |
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/>. */ | |
910fdc79 DB |
20 | |
21 | #include "config.h" | |
22 | #include "system.h" | |
23 | #include "coretypes.h" | |
24 | #include "tm.h" | |
25 | #include "ggc.h" | |
26 | #include "obstack.h" | |
27 | #include "bitmap.h" | |
910fdc79 DB |
28 | #include "flags.h" |
29 | #include "rtl.h" | |
30 | #include "tm_p.h" | |
31 | #include "hard-reg-set.h" | |
32 | #include "basic-block.h" | |
33 | #include "output.h" | |
910fdc79 | 34 | #include "tree.h" |
910fdc79 DB |
35 | #include "tree-flow.h" |
36 | #include "tree-inline.h" | |
37 | #include "varray.h" | |
ce1b6498 RG |
38 | #include "diagnostic.h" |
39 | #include "toplev.h" | |
726a989a | 40 | #include "gimple.h" |
910fdc79 DB |
41 | #include "hashtab.h" |
42 | #include "function.h" | |
43 | #include "cgraph.h" | |
44 | #include "tree-pass.h" | |
45 | #include "timevar.h" | |
46 | #include "alloc-pool.h" | |
47 | #include "splay-tree.h" | |
a916f21d | 48 | #include "params.h" |
4ee00913 | 49 | #include "cgraph.h" |
c58936b6 | 50 | #include "alias.h" |
38635499 | 51 | #include "pointer-set.h" |
910fdc79 DB |
52 | |
53 | /* The idea behind this analyzer is to generate set constraints from the | |
54 | program, then solve the resulting constraints in order to generate the | |
c58936b6 | 55 | points-to sets. |
910fdc79 DB |
56 | |
57 | Set constraints are a way of modeling program analysis problems that | |
58 | involve sets. They consist of an inclusion constraint language, | |
59 | describing the variables (each variable is a set) and operations that | |
60 | are involved on the variables, and a set of rules that derive facts | |
61 | from these operations. To solve a system of set constraints, you derive | |
62 | all possible facts under the rules, which gives you the correct sets | |
63 | as a consequence. | |
64 | ||
65 | See "Efficient Field-sensitive pointer analysis for C" by "David | |
66 | J. Pearce and Paul H. J. Kelly and Chris Hankin, at | |
67 | http://citeseer.ist.psu.edu/pearce04efficient.html | |
68 | ||
69 | Also see "Ultra-fast Aliasing Analysis using CLA: A Million Lines | |
70 | of C Code in a Second" by ""Nevin Heintze and Olivier Tardieu" at | |
c58936b6 DB |
71 | http://citeseer.ist.psu.edu/heintze01ultrafast.html |
72 | ||
73 | There are three types of real constraint expressions, DEREF, | |
3e5937d7 | 74 | ADDRESSOF, and SCALAR. Each constraint expression consists |
c58936b6 | 75 | of a constraint type, a variable, and an offset. |
910fdc79 | 76 | |
910fdc79 DB |
77 | SCALAR is a constraint expression type used to represent x, whether |
78 | it appears on the LHS or the RHS of a statement. | |
79 | DEREF is a constraint expression type used to represent *x, whether | |
c58936b6 | 80 | it appears on the LHS or the RHS of a statement. |
910fdc79 | 81 | ADDRESSOF is a constraint expression used to represent &x, whether |
607fb860 | 82 | it appears on the LHS or the RHS of a statement. |
c58936b6 | 83 | |
910fdc79 DB |
84 | Each pointer variable in the program is assigned an integer id, and |
85 | each field of a structure variable is assigned an integer id as well. | |
c58936b6 | 86 | |
910fdc79 DB |
87 | Structure variables are linked to their list of fields through a "next |
88 | field" in each variable that points to the next field in offset | |
c58936b6 DB |
89 | order. |
90 | Each variable for a structure field has | |
910fdc79 DB |
91 | |
92 | 1. "size", that tells the size in bits of that field. | |
93 | 2. "fullsize, that tells the size in bits of the entire structure. | |
94 | 3. "offset", that tells the offset in bits from the beginning of the | |
95 | structure to this field. | |
96 | ||
c58936b6 | 97 | Thus, |
910fdc79 DB |
98 | struct f |
99 | { | |
100 | int a; | |
101 | int b; | |
102 | } foo; | |
103 | int *bar; | |
104 | ||
105 | looks like | |
106 | ||
107 | foo.a -> id 1, size 32, offset 0, fullsize 64, next foo.b | |
108 | foo.b -> id 2, size 32, offset 32, fullsize 64, next NULL | |
109 | bar -> id 3, size 32, offset 0, fullsize 32, next NULL | |
110 | ||
c58936b6 | 111 | |
910fdc79 DB |
112 | In order to solve the system of set constraints, the following is |
113 | done: | |
114 | ||
115 | 1. Each constraint variable x has a solution set associated with it, | |
116 | Sol(x). | |
c58936b6 | 117 | |
910fdc79 DB |
118 | 2. Constraints are separated into direct, copy, and complex. |
119 | Direct constraints are ADDRESSOF constraints that require no extra | |
120 | processing, such as P = &Q | |
121 | Copy constraints are those of the form P = Q. | |
2941f691 DB |
122 | Complex constraints are all the constraints involving dereferences |
123 | and offsets (including offsetted copies). | |
c58936b6 | 124 | |
910fdc79 | 125 | 3. All direct constraints of the form P = &Q are processed, such |
c58936b6 | 126 | that Q is added to Sol(P) |
910fdc79 DB |
127 | |
128 | 4. All complex constraints for a given constraint variable are stored in a | |
c58936b6 | 129 | linked list attached to that variable's node. |
910fdc79 DB |
130 | |
131 | 5. A directed graph is built out of the copy constraints. Each | |
c58936b6 | 132 | constraint variable is a node in the graph, and an edge from |
910fdc79 | 133 | Q to P is added for each copy constraint of the form P = Q |
c58936b6 | 134 | |
910fdc79 DB |
135 | 6. The graph is then walked, and solution sets are |
136 | propagated along the copy edges, such that an edge from Q to P | |
137 | causes Sol(P) <- Sol(P) union Sol(Q). | |
c58936b6 | 138 | |
910fdc79 | 139 | 7. As we visit each node, all complex constraints associated with |
607fb860 | 140 | that node are processed by adding appropriate copy edges to the graph, or the |
c58936b6 | 141 | appropriate variables to the solution set. |
910fdc79 DB |
142 | |
143 | 8. The process of walking the graph is iterated until no solution | |
144 | sets change. | |
145 | ||
146 | Prior to walking the graph in steps 6 and 7, We perform static | |
c58936b6 | 147 | cycle elimination on the constraint graph, as well |
910fdc79 | 148 | as off-line variable substitution. |
c58936b6 | 149 | |
910fdc79 DB |
150 | TODO: Adding offsets to pointer-to-structures can be handled (IE not punted |
151 | on and turned into anything), but isn't. You can just see what offset | |
152 | inside the pointed-to struct it's going to access. | |
c58936b6 | 153 | |
910fdc79 | 154 | TODO: Constant bounded arrays can be handled as if they were structs of the |
c58936b6 | 155 | same number of elements. |
910fdc79 DB |
156 | |
157 | TODO: Modeling heap and incoming pointers becomes much better if we | |
158 | add fields to them as we discover them, which we could do. | |
159 | ||
160 | TODO: We could handle unions, but to be honest, it's probably not | |
161 | worth the pain or slowdown. */ | |
162 | ||
c58936b6 | 163 | static GTY ((if_marked ("tree_map_marked_p"), param_is (struct tree_map))) |
21392f19 DB |
164 | htab_t heapvar_for_stmt; |
165 | ||
910fdc79 | 166 | static bool use_field_sensitive = true; |
4ee00913 | 167 | static int in_ipa_mode = 0; |
3e5937d7 DB |
168 | |
169 | /* Used for predecessor bitmaps. */ | |
4ee00913 | 170 | static bitmap_obstack predbitmap_obstack; |
3e5937d7 DB |
171 | |
172 | /* Used for points-to sets. */ | |
173 | static bitmap_obstack pta_obstack; | |
174 | ||
175 | /* Used for oldsolution members of variables. */ | |
176 | static bitmap_obstack oldpta_obstack; | |
177 | ||
178 | /* Used for per-solver-iteration bitmaps. */ | |
4ee00913 DB |
179 | static bitmap_obstack iteration_obstack; |
180 | ||
910fdc79 | 181 | static unsigned int create_variable_info_for (tree, const char *); |
3e5937d7 DB |
182 | typedef struct constraint_graph *constraint_graph_t; |
183 | static void unify_nodes (constraint_graph_t, unsigned int, unsigned int, bool); | |
910fdc79 | 184 | |
5006671f RG |
185 | struct constraint; |
186 | typedef struct constraint *constraint_t; | |
187 | ||
910fdc79 | 188 | DEF_VEC_P(constraint_t); |
b5efa470 | 189 | DEF_VEC_ALLOC_P(constraint_t,heap); |
910fdc79 | 190 | |
4ee00913 DB |
191 | #define EXECUTE_IF_IN_NONNULL_BITMAP(a, b, c, d) \ |
192 | if (a) \ | |
193 | EXECUTE_IF_SET_IN_BITMAP (a, b, c, d) | |
194 | ||
910fdc79 DB |
195 | static struct constraint_stats |
196 | { | |
197 | unsigned int total_vars; | |
3e5937d7 | 198 | unsigned int nonpointer_vars; |
910fdc79 DB |
199 | unsigned int unified_vars_static; |
200 | unsigned int unified_vars_dynamic; | |
201 | unsigned int iterations; | |
4ee00913 | 202 | unsigned int num_edges; |
3e5937d7 DB |
203 | unsigned int num_implicit_edges; |
204 | unsigned int points_to_sets_created; | |
910fdc79 DB |
205 | } stats; |
206 | ||
207 | struct variable_info | |
208 | { | |
209 | /* ID of this variable */ | |
210 | unsigned int id; | |
211 | ||
910fdc79 DB |
212 | /* True if this is a variable created by the constraint analysis, such as |
213 | heap variables and constraints we had to break up. */ | |
74d27244 | 214 | unsigned int is_artificial_var : 1; |
c58936b6 | 215 | |
13c2c08b DB |
216 | /* True if this is a special variable whose solution set should not be |
217 | changed. */ | |
74d27244 | 218 | unsigned int is_special_var : 1; |
910fdc79 DB |
219 | |
220 | /* True for variables whose size is not known or variable. */ | |
74d27244 | 221 | unsigned int is_unknown_size_var : 1; |
910fdc79 | 222 | |
e5bae89b RG |
223 | /* True for (sub-)fields that represent a whole variable. */ |
224 | unsigned int is_full_var : 1; | |
225 | ||
e8ca4159 | 226 | /* True if this is a heap variable. */ |
74d27244 RG |
227 | unsigned int is_heap_var : 1; |
228 | ||
229 | /* True if this is a variable tracking a restrict pointer source. */ | |
230 | unsigned int is_restrict_var : 1; | |
e8ca4159 | 231 | |
9e39dba6 RG |
232 | /* True if this field may contain pointers. */ |
233 | unsigned int may_have_pointers : 1; | |
234 | ||
0bbf2ffa RG |
235 | /* True if this represents a global variable. */ |
236 | unsigned int is_global_var : 1; | |
237 | ||
795a337a RG |
238 | /* A link to the variable for the next field in this structure. */ |
239 | struct variable_info *next; | |
240 | ||
241 | /* Offset of this variable, in bits, from the base variable */ | |
242 | unsigned HOST_WIDE_INT offset; | |
243 | ||
244 | /* Size of the variable, in bits. */ | |
245 | unsigned HOST_WIDE_INT size; | |
246 | ||
247 | /* Full size of the base variable, in bits. */ | |
248 | unsigned HOST_WIDE_INT fullsize; | |
249 | ||
250 | /* Name of this variable */ | |
251 | const char *name; | |
252 | ||
253 | /* Tree that this variable is associated with. */ | |
254 | tree decl; | |
255 | ||
910fdc79 DB |
256 | /* Points-to set for this variable. */ |
257 | bitmap solution; | |
258 | ||
3e5937d7 DB |
259 | /* Old points-to set for this variable. */ |
260 | bitmap oldsolution; | |
910fdc79 DB |
261 | }; |
262 | typedef struct variable_info *varinfo_t; | |
263 | ||
264 | static varinfo_t first_vi_for_offset (varinfo_t, unsigned HOST_WIDE_INT); | |
5006671f RG |
265 | static varinfo_t first_or_preceding_vi_for_offset (varinfo_t, |
266 | unsigned HOST_WIDE_INT); | |
0e1f4c6b | 267 | static varinfo_t lookup_vi_for_tree (tree); |
910fdc79 DB |
268 | |
269 | /* Pool of variable info structures. */ | |
270 | static alloc_pool variable_info_pool; | |
271 | ||
272 | DEF_VEC_P(varinfo_t); | |
273 | ||
b5efa470 | 274 | DEF_VEC_ALLOC_P(varinfo_t, heap); |
910fdc79 | 275 | |
38635499 DN |
276 | /* Table of variable info structures for constraint variables. |
277 | Indexed directly by variable info id. */ | |
b5efa470 | 278 | static VEC(varinfo_t,heap) *varmap; |
13c2c08b DB |
279 | |
280 | /* Return the varmap element N */ | |
281 | ||
282 | static inline varinfo_t | |
03190594 | 283 | get_varinfo (unsigned int n) |
13c2c08b | 284 | { |
62e5bf5d | 285 | return VEC_index (varinfo_t, varmap, n); |
13c2c08b | 286 | } |
910fdc79 | 287 | |
b7091901 RG |
288 | /* Static IDs for the special variables. */ |
289 | enum { nothing_id = 0, anything_id = 1, readonly_id = 2, | |
9e39dba6 RG |
290 | escaped_id = 3, nonlocal_id = 4, callused_id = 5, |
291 | storedanything_id = 6, integer_id = 7 }; | |
b7091901 | 292 | |
8bc88f25 RB |
293 | struct GTY(()) heapvar_map { |
294 | struct tree_map map; | |
295 | unsigned HOST_WIDE_INT offset; | |
296 | }; | |
297 | ||
298 | static int | |
299 | heapvar_map_eq (const void *p1, const void *p2) | |
300 | { | |
301 | const struct heapvar_map *h1 = (const struct heapvar_map *)p1; | |
302 | const struct heapvar_map *h2 = (const struct heapvar_map *)p2; | |
303 | return (h1->map.base.from == h2->map.base.from | |
304 | && h1->offset == h2->offset); | |
305 | } | |
306 | ||
307 | static unsigned int | |
308 | heapvar_map_hash (struct heapvar_map *h) | |
309 | { | |
310 | return iterative_hash_host_wide_int (h->offset, | |
311 | htab_hash_pointer (h->map.base.from)); | |
312 | } | |
313 | ||
f5d7990b | 314 | /* Lookup a heap var for FROM, and return it if we find one. */ |
c900f6aa | 315 | |
c58936b6 | 316 | static tree |
8bc88f25 | 317 | heapvar_lookup (tree from, unsigned HOST_WIDE_INT offset) |
c900f6aa | 318 | { |
8bc88f25 RB |
319 | struct heapvar_map *h, in; |
320 | in.map.base.from = from; | |
321 | in.offset = offset; | |
322 | h = (struct heapvar_map *) htab_find_with_hash (heapvar_for_stmt, &in, | |
323 | heapvar_map_hash (&in)); | |
c900f6aa | 324 | if (h) |
8bc88f25 | 325 | return h->map.to; |
c900f6aa DB |
326 | return NULL_TREE; |
327 | } | |
328 | ||
329 | /* Insert a mapping FROM->TO in the heap var for statement | |
330 | hashtable. */ | |
331 | ||
332 | static void | |
8bc88f25 | 333 | heapvar_insert (tree from, unsigned HOST_WIDE_INT offset, tree to) |
c900f6aa | 334 | { |
8bc88f25 | 335 | struct heapvar_map *h; |
c900f6aa DB |
336 | void **loc; |
337 | ||
8bc88f25 RB |
338 | h = GGC_NEW (struct heapvar_map); |
339 | h->map.base.from = from; | |
340 | h->offset = offset; | |
341 | h->map.hash = heapvar_map_hash (h); | |
342 | h->map.to = to; | |
343 | loc = htab_find_slot_with_hash (heapvar_for_stmt, h, h->map.hash, INSERT); | |
344 | gcc_assert (*loc == NULL); | |
345 | *(struct heapvar_map **) loc = h; | |
21392f19 | 346 | } |
c900f6aa | 347 | |
910fdc79 | 348 | /* Return a new variable info structure consisting for a variable |
0bbf2ffa RG |
349 | named NAME, and using constraint graph node NODE. Append it |
350 | to the vector of variable info structures. */ | |
910fdc79 DB |
351 | |
352 | static varinfo_t | |
0bbf2ffa | 353 | new_var_info (tree t, const char *name) |
910fdc79 | 354 | { |
0bbf2ffa | 355 | unsigned index = VEC_length (varinfo_t, varmap); |
c22940cd | 356 | varinfo_t ret = (varinfo_t) pool_alloc (variable_info_pool); |
910fdc79 | 357 | |
0bbf2ffa | 358 | ret->id = index; |
910fdc79 DB |
359 | ret->name = name; |
360 | ret->decl = t; | |
0bbf2ffa RG |
361 | /* Vars without decl are artificial and do not have sub-variables. */ |
362 | ret->is_artificial_var = (t == NULL_TREE); | |
13c2c08b | 363 | ret->is_special_var = false; |
910fdc79 | 364 | ret->is_unknown_size_var = false; |
02583d3c RG |
365 | ret->is_full_var = (t == NULL_TREE); |
366 | ret->is_heap_var = false; | |
367 | ret->is_restrict_var = false; | |
9e39dba6 | 368 | ret->may_have_pointers = true; |
74d27244 | 369 | ret->is_global_var = (t == NULL_TREE); |
0bbf2ffa RG |
370 | if (t && DECL_P (t)) |
371 | ret->is_global_var = is_global_var (t); | |
3e5937d7 DB |
372 | ret->solution = BITMAP_ALLOC (&pta_obstack); |
373 | ret->oldsolution = BITMAP_ALLOC (&oldpta_obstack); | |
910fdc79 | 374 | ret->next = NULL; |
0bbf2ffa RG |
375 | |
376 | VEC_safe_push (varinfo_t, heap, varmap, ret); | |
377 | ||
910fdc79 DB |
378 | return ret; |
379 | } | |
380 | ||
3e5937d7 | 381 | typedef enum {SCALAR, DEREF, ADDRESSOF} constraint_expr_type; |
910fdc79 DB |
382 | |
383 | /* An expression that appears in a constraint. */ | |
384 | ||
c58936b6 | 385 | struct constraint_expr |
910fdc79 DB |
386 | { |
387 | /* Constraint type. */ | |
388 | constraint_expr_type type; | |
389 | ||
390 | /* Variable we are referring to in the constraint. */ | |
391 | unsigned int var; | |
392 | ||
393 | /* Offset, in bits, of this constraint from the beginning of | |
394 | variables it ends up referring to. | |
395 | ||
396 | IOW, in a deref constraint, we would deref, get the result set, | |
397 | then add OFFSET to each member. */ | |
5006671f | 398 | HOST_WIDE_INT offset; |
910fdc79 DB |
399 | }; |
400 | ||
5006671f RG |
401 | /* Use 0x8000... as special unknown offset. */ |
402 | #define UNKNOWN_OFFSET ((HOST_WIDE_INT)-1 << (HOST_BITS_PER_WIDE_INT-1)) | |
403 | ||
4ee00913 DB |
404 | typedef struct constraint_expr ce_s; |
405 | DEF_VEC_O(ce_s); | |
406 | DEF_VEC_ALLOC_O(ce_s, heap); | |
c0d459f0 | 407 | static void get_constraint_for_1 (tree, VEC(ce_s, heap) **, bool); |
1d85354c | 408 | static void get_constraint_for (tree, VEC(ce_s, heap) **); |
4ee00913 | 409 | static void do_deref (VEC (ce_s, heap) **); |
910fdc79 DB |
410 | |
411 | /* Our set constraints are made up of two constraint expressions, one | |
c58936b6 | 412 | LHS, and one RHS. |
910fdc79 DB |
413 | |
414 | As described in the introduction, our set constraints each represent an | |
415 | operation between set valued variables. | |
416 | */ | |
417 | struct constraint | |
418 | { | |
419 | struct constraint_expr lhs; | |
420 | struct constraint_expr rhs; | |
421 | }; | |
422 | ||
423 | /* List of constraints that we use to build the constraint graph from. */ | |
424 | ||
b5efa470 | 425 | static VEC(constraint_t,heap) *constraints; |
910fdc79 DB |
426 | static alloc_pool constraint_pool; |
427 | ||
57250223 DB |
428 | /* The constraint graph is represented as an array of bitmaps |
429 | containing successor nodes. */ | |
910fdc79 DB |
430 | |
431 | struct constraint_graph | |
432 | { | |
3e5937d7 DB |
433 | /* Size of this graph, which may be different than the number of |
434 | nodes in the variable map. */ | |
435 | unsigned int size; | |
436 | ||
437 | /* Explicit successors of each node. */ | |
57250223 | 438 | bitmap *succs; |
3e5937d7 DB |
439 | |
440 | /* Implicit predecessors of each node (Used for variable | |
441 | substitution). */ | |
442 | bitmap *implicit_preds; | |
443 | ||
444 | /* Explicit predecessors of each node (Used for variable substitution). */ | |
57250223 | 445 | bitmap *preds; |
910fdc79 | 446 | |
3e5937d7 DB |
447 | /* Indirect cycle representatives, or -1 if the node has no indirect |
448 | cycles. */ | |
449 | int *indirect_cycles; | |
450 | ||
451 | /* Representative node for a node. rep[a] == a unless the node has | |
452 | been unified. */ | |
453 | unsigned int *rep; | |
454 | ||
7b765bed | 455 | /* Equivalence class representative for a label. This is used for |
3e5937d7 DB |
456 | variable substitution. */ |
457 | int *eq_rep; | |
458 | ||
aa46c8a3 DB |
459 | /* Pointer equivalence label for a node. All nodes with the same |
460 | pointer equivalence label can be unified together at some point | |
461 | (either during constraint optimization or after the constraint | |
462 | graph is built). */ | |
7b765bed DB |
463 | unsigned int *pe; |
464 | ||
465 | /* Pointer equivalence representative for a label. This is used to | |
466 | handle nodes that are pointer equivalent but not location | |
467 | equivalent. We can unite these once the addressof constraints | |
468 | are transformed into initial points-to sets. */ | |
469 | int *pe_rep; | |
470 | ||
471 | /* Pointer equivalence label for each node, used during variable | |
472 | substitution. */ | |
473 | unsigned int *pointer_label; | |
474 | ||
475 | /* Location equivalence label for each node, used during location | |
476 | equivalence finding. */ | |
477 | unsigned int *loc_label; | |
478 | ||
479 | /* Pointed-by set for each node, used during location equivalence | |
480 | finding. This is pointed-by rather than pointed-to, because it | |
481 | is constructed using the predecessor graph. */ | |
482 | bitmap *pointed_by; | |
483 | ||
484 | /* Points to sets for pointer equivalence. This is *not* the actual | |
485 | points-to sets for nodes. */ | |
486 | bitmap *points_to; | |
3e5937d7 DB |
487 | |
488 | /* Bitmap of nodes where the bit is set if the node is a direct | |
489 | node. Used for variable substitution. */ | |
490 | sbitmap direct_nodes; | |
491 | ||
7b765bed DB |
492 | /* Bitmap of nodes where the bit is set if the node is address |
493 | taken. Used for variable substitution. */ | |
494 | bitmap address_taken; | |
495 | ||
3e5937d7 DB |
496 | /* Vector of complex constraints for each graph node. Complex |
497 | constraints are those involving dereferences or offsets that are | |
498 | not 0. */ | |
499 | VEC(constraint_t,heap) **complex; | |
500 | }; | |
910fdc79 DB |
501 | |
502 | static constraint_graph_t graph; | |
503 | ||
3e5937d7 DB |
504 | /* During variable substitution and the offline version of indirect |
505 | cycle finding, we create nodes to represent dereferences and | |
506 | address taken constraints. These represent where these start and | |
507 | end. */ | |
508 | #define FIRST_REF_NODE (VEC_length (varinfo_t, varmap)) | |
509 | #define LAST_REF_NODE (FIRST_REF_NODE + (FIRST_REF_NODE - 1)) | |
3e5937d7 DB |
510 | |
511 | /* Return the representative node for NODE, if NODE has been unioned | |
512 | with another NODE. | |
513 | This function performs path compression along the way to finding | |
514 | the representative. */ | |
515 | ||
516 | static unsigned int | |
517 | find (unsigned int node) | |
518 | { | |
519 | gcc_assert (node < graph->size); | |
520 | if (graph->rep[node] != node) | |
521 | return graph->rep[node] = find (graph->rep[node]); | |
522 | return node; | |
523 | } | |
524 | ||
525 | /* Union the TO and FROM nodes to the TO nodes. | |
526 | Note that at some point in the future, we may want to do | |
527 | union-by-rank, in which case we are going to have to return the | |
528 | node we unified to. */ | |
529 | ||
530 | static bool | |
531 | unite (unsigned int to, unsigned int from) | |
532 | { | |
533 | gcc_assert (to < graph->size && from < graph->size); | |
534 | if (to != from && graph->rep[from] != to) | |
535 | { | |
536 | graph->rep[from] = to; | |
537 | return true; | |
538 | } | |
539 | return false; | |
540 | } | |
541 | ||
910fdc79 DB |
542 | /* Create a new constraint consisting of LHS and RHS expressions. */ |
543 | ||
c58936b6 | 544 | static constraint_t |
910fdc79 DB |
545 | new_constraint (const struct constraint_expr lhs, |
546 | const struct constraint_expr rhs) | |
547 | { | |
c22940cd | 548 | constraint_t ret = (constraint_t) pool_alloc (constraint_pool); |
910fdc79 DB |
549 | ret->lhs = lhs; |
550 | ret->rhs = rhs; | |
551 | return ret; | |
552 | } | |
553 | ||
554 | /* Print out constraint C to FILE. */ | |
555 | ||
5006671f | 556 | static void |
910fdc79 DB |
557 | dump_constraint (FILE *file, constraint_t c) |
558 | { | |
559 | if (c->lhs.type == ADDRESSOF) | |
560 | fprintf (file, "&"); | |
561 | else if (c->lhs.type == DEREF) | |
c58936b6 | 562 | fprintf (file, "*"); |
5006671f RG |
563 | fprintf (file, "%s", get_varinfo (c->lhs.var)->name); |
564 | if (c->lhs.offset == UNKNOWN_OFFSET) | |
565 | fprintf (file, " + UNKNOWN"); | |
566 | else if (c->lhs.offset != 0) | |
910fdc79 DB |
567 | fprintf (file, " + " HOST_WIDE_INT_PRINT_DEC, c->lhs.offset); |
568 | fprintf (file, " = "); | |
569 | if (c->rhs.type == ADDRESSOF) | |
570 | fprintf (file, "&"); | |
571 | else if (c->rhs.type == DEREF) | |
572 | fprintf (file, "*"); | |
5006671f RG |
573 | fprintf (file, "%s", get_varinfo (c->rhs.var)->name); |
574 | if (c->rhs.offset == UNKNOWN_OFFSET) | |
575 | fprintf (file, " + UNKNOWN"); | |
576 | else if (c->rhs.offset != 0) | |
910fdc79 DB |
577 | fprintf (file, " + " HOST_WIDE_INT_PRINT_DEC, c->rhs.offset); |
578 | fprintf (file, "\n"); | |
579 | } | |
580 | ||
5006671f RG |
581 | |
582 | void debug_constraint (constraint_t); | |
583 | void debug_constraints (void); | |
584 | void debug_constraint_graph (void); | |
585 | void debug_solution_for_var (unsigned int); | |
586 | void debug_sa_points_to_info (void); | |
587 | ||
910fdc79 DB |
588 | /* Print out constraint C to stderr. */ |
589 | ||
590 | void | |
591 | debug_constraint (constraint_t c) | |
592 | { | |
593 | dump_constraint (stderr, c); | |
594 | } | |
595 | ||
596 | /* Print out all constraints to FILE */ | |
597 | ||
5006671f | 598 | static void |
910fdc79 DB |
599 | dump_constraints (FILE *file) |
600 | { | |
601 | int i; | |
602 | constraint_t c; | |
603 | for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++) | |
604 | dump_constraint (file, c); | |
605 | } | |
606 | ||
607 | /* Print out all constraints to stderr. */ | |
608 | ||
609 | void | |
610 | debug_constraints (void) | |
611 | { | |
612 | dump_constraints (stderr); | |
613 | } | |
614 | ||
fc93bcb6 FP |
615 | /* Print out to FILE the edge in the constraint graph that is created by |
616 | constraint c. The edge may have a label, depending on the type of | |
617 | constraint that it represents. If complex1, e.g: a = *b, then the label | |
618 | is "=*", if complex2, e.g: *a = b, then the label is "*=", if | |
619 | complex with an offset, e.g: a = b + 8, then the label is "+". | |
620 | Otherwise the edge has no label. */ | |
621 | ||
5006671f | 622 | static void |
fc93bcb6 FP |
623 | dump_constraint_edge (FILE *file, constraint_t c) |
624 | { | |
625 | if (c->rhs.type != ADDRESSOF) | |
626 | { | |
5006671f RG |
627 | const char *src = get_varinfo (c->rhs.var)->name; |
628 | const char *dst = get_varinfo (c->lhs.var)->name; | |
fc93bcb6 FP |
629 | fprintf (file, " \"%s\" -> \"%s\" ", src, dst); |
630 | /* Due to preprocessing of constraints, instructions like *a = *b are | |
631 | illegal; thus, we do not have to handle such cases. */ | |
632 | if (c->lhs.type == DEREF) | |
633 | fprintf (file, " [ label=\"*=\" ] ;\n"); | |
634 | else if (c->rhs.type == DEREF) | |
635 | fprintf (file, " [ label=\"=*\" ] ;\n"); | |
636 | else | |
637 | { | |
638 | /* We must check the case where the constraint is an offset. | |
639 | In this case, it is treated as a complex constraint. */ | |
640 | if (c->rhs.offset != c->lhs.offset) | |
641 | fprintf (file, " [ label=\"+\" ] ;\n"); | |
642 | else | |
643 | fprintf (file, " ;\n"); | |
644 | } | |
645 | } | |
646 | } | |
647 | ||
648 | /* Print the constraint graph in dot format. */ | |
649 | ||
5006671f | 650 | static void |
fc93bcb6 FP |
651 | dump_constraint_graph (FILE *file) |
652 | { | |
653 | unsigned int i=0, size; | |
654 | constraint_t c; | |
655 | ||
656 | /* Only print the graph if it has already been initialized: */ | |
657 | if (!graph) | |
658 | return; | |
659 | ||
660 | /* Print the constraints used to produce the constraint graph. The | |
661 | constraints will be printed as comments in the dot file: */ | |
662 | fprintf (file, "\n\n/* Constraints used in the constraint graph:\n"); | |
663 | dump_constraints (file); | |
664 | fprintf (file, "*/\n"); | |
665 | ||
666 | /* Prints the header of the dot file: */ | |
667 | fprintf (file, "\n\n// The constraint graph in dot format:\n"); | |
668 | fprintf (file, "strict digraph {\n"); | |
669 | fprintf (file, " node [\n shape = box\n ]\n"); | |
670 | fprintf (file, " edge [\n fontsize = \"12\"\n ]\n"); | |
671 | fprintf (file, "\n // List of nodes in the constraint graph:\n"); | |
672 | ||
673 | /* The next lines print the nodes in the graph. In order to get the | |
674 | number of nodes in the graph, we must choose the minimum between the | |
675 | vector VEC (varinfo_t, varmap) and graph->size. If the graph has not | |
676 | yet been initialized, then graph->size == 0, otherwise we must only | |
677 | read nodes that have an entry in VEC (varinfo_t, varmap). */ | |
678 | size = VEC_length (varinfo_t, varmap); | |
679 | size = size < graph->size ? size : graph->size; | |
680 | for (i = 0; i < size; i++) | |
681 | { | |
5006671f | 682 | const char *name = get_varinfo (graph->rep[i])->name; |
fc93bcb6 FP |
683 | fprintf (file, " \"%s\" ;\n", name); |
684 | } | |
685 | ||
686 | /* Go over the list of constraints printing the edges in the constraint | |
687 | graph. */ | |
688 | fprintf (file, "\n // The constraint edges:\n"); | |
689 | for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++) | |
690 | if (c) | |
691 | dump_constraint_edge (file, c); | |
692 | ||
693 | /* Prints the tail of the dot file. By now, only the closing bracket. */ | |
694 | fprintf (file, "}\n\n\n"); | |
695 | } | |
696 | ||
697 | /* Print out the constraint graph to stderr. */ | |
698 | ||
699 | void | |
700 | debug_constraint_graph (void) | |
701 | { | |
702 | dump_constraint_graph (stderr); | |
703 | } | |
704 | ||
c58936b6 | 705 | /* SOLVER FUNCTIONS |
910fdc79 DB |
706 | |
707 | The solver is a simple worklist solver, that works on the following | |
708 | algorithm: | |
c58936b6 | 709 | |
3e5937d7 DB |
710 | sbitmap changed_nodes = all zeroes; |
711 | changed_count = 0; | |
712 | For each node that is not already collapsed: | |
713 | changed_count++; | |
714 | set bit in changed nodes | |
910fdc79 | 715 | |
910fdc79 DB |
716 | while (changed_count > 0) |
717 | { | |
718 | compute topological ordering for constraint graph | |
c58936b6 | 719 | |
910fdc79 DB |
720 | find and collapse cycles in the constraint graph (updating |
721 | changed if necessary) | |
c58936b6 | 722 | |
910fdc79 DB |
723 | for each node (n) in the graph in topological order: |
724 | changed_count--; | |
725 | ||
726 | Process each complex constraint associated with the node, | |
727 | updating changed if necessary. | |
728 | ||
729 | For each outgoing edge from n, propagate the solution from n to | |
730 | the destination of the edge, updating changed as necessary. | |
731 | ||
732 | } */ | |
733 | ||
734 | /* Return true if two constraint expressions A and B are equal. */ | |
735 | ||
736 | static bool | |
737 | constraint_expr_equal (struct constraint_expr a, struct constraint_expr b) | |
738 | { | |
4ee00913 | 739 | return a.type == b.type && a.var == b.var && a.offset == b.offset; |
910fdc79 DB |
740 | } |
741 | ||
742 | /* Return true if constraint expression A is less than constraint expression | |
743 | B. This is just arbitrary, but consistent, in order to give them an | |
744 | ordering. */ | |
745 | ||
746 | static bool | |
747 | constraint_expr_less (struct constraint_expr a, struct constraint_expr b) | |
748 | { | |
749 | if (a.type == b.type) | |
750 | { | |
751 | if (a.var == b.var) | |
752 | return a.offset < b.offset; | |
753 | else | |
754 | return a.var < b.var; | |
755 | } | |
756 | else | |
757 | return a.type < b.type; | |
758 | } | |
759 | ||
760 | /* Return true if constraint A is less than constraint B. This is just | |
761 | arbitrary, but consistent, in order to give them an ordering. */ | |
762 | ||
763 | static bool | |
764 | constraint_less (const constraint_t a, const constraint_t b) | |
765 | { | |
766 | if (constraint_expr_less (a->lhs, b->lhs)) | |
767 | return true; | |
768 | else if (constraint_expr_less (b->lhs, a->lhs)) | |
769 | return false; | |
770 | else | |
771 | return constraint_expr_less (a->rhs, b->rhs); | |
772 | } | |
773 | ||
774 | /* Return true if two constraints A and B are equal. */ | |
c58936b6 | 775 | |
910fdc79 DB |
776 | static bool |
777 | constraint_equal (struct constraint a, struct constraint b) | |
778 | { | |
c58936b6 | 779 | return constraint_expr_equal (a.lhs, b.lhs) |
910fdc79 DB |
780 | && constraint_expr_equal (a.rhs, b.rhs); |
781 | } | |
782 | ||
783 | ||
784 | /* Find a constraint LOOKFOR in the sorted constraint vector VEC */ | |
785 | ||
786 | static constraint_t | |
b5efa470 | 787 | constraint_vec_find (VEC(constraint_t,heap) *vec, |
910fdc79 DB |
788 | struct constraint lookfor) |
789 | { | |
c58936b6 | 790 | unsigned int place; |
910fdc79 DB |
791 | constraint_t found; |
792 | ||
793 | if (vec == NULL) | |
794 | return NULL; | |
795 | ||
796 | place = VEC_lower_bound (constraint_t, vec, &lookfor, constraint_less); | |
797 | if (place >= VEC_length (constraint_t, vec)) | |
798 | return NULL; | |
799 | found = VEC_index (constraint_t, vec, place); | |
800 | if (!constraint_equal (*found, lookfor)) | |
801 | return NULL; | |
802 | return found; | |
803 | } | |
804 | ||
805 | /* Union two constraint vectors, TO and FROM. Put the result in TO. */ | |
806 | ||
807 | static void | |
b5efa470 DB |
808 | constraint_set_union (VEC(constraint_t,heap) **to, |
809 | VEC(constraint_t,heap) **from) | |
910fdc79 DB |
810 | { |
811 | int i; | |
812 | constraint_t c; | |
813 | ||
814 | for (i = 0; VEC_iterate (constraint_t, *from, i, c); i++) | |
815 | { | |
816 | if (constraint_vec_find (*to, *c) == NULL) | |
817 | { | |
818 | unsigned int place = VEC_lower_bound (constraint_t, *to, c, | |
819 | constraint_less); | |
b5efa470 | 820 | VEC_safe_insert (constraint_t, heap, *to, place, c); |
910fdc79 DB |
821 | } |
822 | } | |
823 | } | |
824 | ||
5006671f RG |
825 | /* Expands the solution in SET to all sub-fields of variables included. |
826 | Union the expanded result into RESULT. */ | |
827 | ||
828 | static void | |
829 | solution_set_expand (bitmap result, bitmap set) | |
830 | { | |
831 | bitmap_iterator bi; | |
832 | bitmap vars = NULL; | |
833 | unsigned j; | |
834 | ||
835 | /* In a first pass record all variables we need to add all | |
836 | sub-fields off. This avoids quadratic behavior. */ | |
837 | EXECUTE_IF_SET_IN_BITMAP (set, 0, j, bi) | |
838 | { | |
839 | varinfo_t v = get_varinfo (j); | |
840 | if (v->is_artificial_var | |
841 | || v->is_full_var) | |
842 | continue; | |
843 | v = lookup_vi_for_tree (v->decl); | |
844 | if (vars == NULL) | |
845 | vars = BITMAP_ALLOC (NULL); | |
846 | bitmap_set_bit (vars, v->id); | |
847 | } | |
848 | ||
849 | /* In the second pass now do the addition to the solution and | |
850 | to speed up solving add it to the delta as well. */ | |
851 | if (vars != NULL) | |
852 | { | |
853 | EXECUTE_IF_SET_IN_BITMAP (vars, 0, j, bi) | |
854 | { | |
855 | varinfo_t v = get_varinfo (j); | |
856 | for (; v != NULL; v = v->next) | |
857 | bitmap_set_bit (result, v->id); | |
858 | } | |
859 | BITMAP_FREE (vars); | |
860 | } | |
861 | } | |
862 | ||
910fdc79 DB |
863 | /* Take a solution set SET, add OFFSET to each member of the set, and |
864 | overwrite SET with the result when done. */ | |
865 | ||
866 | static void | |
5006671f | 867 | solution_set_add (bitmap set, HOST_WIDE_INT offset) |
910fdc79 DB |
868 | { |
869 | bitmap result = BITMAP_ALLOC (&iteration_obstack); | |
870 | unsigned int i; | |
871 | bitmap_iterator bi; | |
872 | ||
5006671f RG |
873 | /* If the offset is unknown we have to expand the solution to |
874 | all subfields. */ | |
875 | if (offset == UNKNOWN_OFFSET) | |
876 | { | |
877 | solution_set_expand (set, set); | |
878 | return; | |
879 | } | |
880 | ||
910fdc79 DB |
881 | EXECUTE_IF_SET_IN_BITMAP (set, 0, i, bi) |
882 | { | |
e5bae89b | 883 | varinfo_t vi = get_varinfo (i); |
c58936b6 | 884 | |
e5bae89b RG |
885 | /* If this is a variable with just one field just set its bit |
886 | in the result. */ | |
887 | if (vi->is_artificial_var | |
888 | || vi->is_unknown_size_var | |
889 | || vi->is_full_var) | |
890 | bitmap_set_bit (result, i); | |
891 | else | |
910fdc79 | 892 | { |
e5bae89b | 893 | unsigned HOST_WIDE_INT fieldoffset = vi->offset + offset; |
5006671f RG |
894 | |
895 | /* If the offset makes the pointer point to before the | |
896 | variable use offset zero for the field lookup. */ | |
897 | if (offset < 0 | |
898 | && fieldoffset > vi->offset) | |
899 | fieldoffset = 0; | |
900 | ||
901 | if (offset != 0) | |
902 | vi = first_or_preceding_vi_for_offset (vi, fieldoffset); | |
903 | ||
904 | bitmap_set_bit (result, vi->id); | |
e5bae89b RG |
905 | /* If the result is not exactly at fieldoffset include the next |
906 | field as well. See get_constraint_for_ptr_offset for more | |
907 | rationale. */ | |
5006671f RG |
908 | if (vi->offset != fieldoffset |
909 | && vi->next != NULL) | |
910 | bitmap_set_bit (result, vi->next->id); | |
910fdc79 DB |
911 | } |
912 | } | |
c58936b6 DB |
913 | |
914 | bitmap_copy (set, result); | |
910fdc79 DB |
915 | BITMAP_FREE (result); |
916 | } | |
917 | ||
918 | /* Union solution sets TO and FROM, and add INC to each member of FROM in the | |
919 | process. */ | |
920 | ||
921 | static bool | |
5006671f | 922 | set_union_with_increment (bitmap to, bitmap from, HOST_WIDE_INT inc) |
910fdc79 DB |
923 | { |
924 | if (inc == 0) | |
925 | return bitmap_ior_into (to, from); | |
926 | else | |
927 | { | |
928 | bitmap tmp; | |
929 | bool res; | |
930 | ||
931 | tmp = BITMAP_ALLOC (&iteration_obstack); | |
932 | bitmap_copy (tmp, from); | |
933 | solution_set_add (tmp, inc); | |
934 | res = bitmap_ior_into (to, tmp); | |
935 | BITMAP_FREE (tmp); | |
936 | return res; | |
937 | } | |
938 | } | |
939 | ||
3e5937d7 DB |
940 | /* Insert constraint C into the list of complex constraints for graph |
941 | node VAR. */ | |
910fdc79 DB |
942 | |
943 | static void | |
3e5937d7 DB |
944 | insert_into_complex (constraint_graph_t graph, |
945 | unsigned int var, constraint_t c) | |
910fdc79 | 946 | { |
3e5937d7 DB |
947 | VEC (constraint_t, heap) *complex = graph->complex[var]; |
948 | unsigned int place = VEC_lower_bound (constraint_t, complex, c, | |
910fdc79 | 949 | constraint_less); |
3e5937d7 DB |
950 | |
951 | /* Only insert constraints that do not already exist. */ | |
952 | if (place >= VEC_length (constraint_t, complex) | |
953 | || !constraint_equal (*c, *VEC_index (constraint_t, complex, place))) | |
954 | VEC_safe_insert (constraint_t, heap, graph->complex[var], place, c); | |
910fdc79 DB |
955 | } |
956 | ||
957 | ||
910fdc79 DB |
958 | /* Condense two variable nodes into a single variable node, by moving |
959 | all associated info from SRC to TO. */ | |
960 | ||
c58936b6 | 961 | static void |
3e5937d7 DB |
962 | merge_node_constraints (constraint_graph_t graph, unsigned int to, |
963 | unsigned int from) | |
910fdc79 | 964 | { |
910fdc79 DB |
965 | unsigned int i; |
966 | constraint_t c; | |
c58936b6 | 967 | |
3e5937d7 | 968 | gcc_assert (find (from) == to); |
c58936b6 | 969 | |
910fdc79 | 970 | /* Move all complex constraints from src node into to node */ |
3e5937d7 | 971 | for (i = 0; VEC_iterate (constraint_t, graph->complex[from], i, c); i++) |
910fdc79 DB |
972 | { |
973 | /* In complex constraints for node src, we may have either | |
3e5937d7 DB |
974 | a = *src, and *src = a, or an offseted constraint which are |
975 | always added to the rhs node's constraints. */ | |
c58936b6 | 976 | |
910fdc79 DB |
977 | if (c->rhs.type == DEREF) |
978 | c->rhs.var = to; | |
3e5937d7 | 979 | else if (c->lhs.type == DEREF) |
910fdc79 | 980 | c->lhs.var = to; |
3e5937d7 DB |
981 | else |
982 | c->rhs.var = to; | |
910fdc79 | 983 | } |
3e5937d7 DB |
984 | constraint_set_union (&graph->complex[to], &graph->complex[from]); |
985 | VEC_free (constraint_t, heap, graph->complex[from]); | |
986 | graph->complex[from] = NULL; | |
910fdc79 DB |
987 | } |
988 | ||
910fdc79 DB |
989 | |
990 | /* Remove edges involving NODE from GRAPH. */ | |
991 | ||
992 | static void | |
993 | clear_edges_for_node (constraint_graph_t graph, unsigned int node) | |
994 | { | |
57250223 | 995 | if (graph->succs[node]) |
3e5937d7 | 996 | BITMAP_FREE (graph->succs[node]); |
f71ef09d DB |
997 | } |
998 | ||
910fdc79 DB |
999 | /* Merge GRAPH nodes FROM and TO into node TO. */ |
1000 | ||
1001 | static void | |
c58936b6 | 1002 | merge_graph_nodes (constraint_graph_t graph, unsigned int to, |
910fdc79 DB |
1003 | unsigned int from) |
1004 | { | |
3e5937d7 | 1005 | if (graph->indirect_cycles[from] != -1) |
4ee00913 | 1006 | { |
3e5937d7 DB |
1007 | /* If we have indirect cycles with the from node, and we have |
1008 | none on the to node, the to node has indirect cycles from the | |
1009 | from node now that they are unified. | |
1010 | If indirect cycles exist on both, unify the nodes that they | |
1011 | are in a cycle with, since we know they are in a cycle with | |
1012 | each other. */ | |
1013 | if (graph->indirect_cycles[to] == -1) | |
7b765bed | 1014 | graph->indirect_cycles[to] = graph->indirect_cycles[from]; |
4ee00913 | 1015 | } |
910fdc79 | 1016 | |
57250223 DB |
1017 | /* Merge all the successor edges. */ |
1018 | if (graph->succs[from]) | |
4ee00913 | 1019 | { |
57250223 | 1020 | if (!graph->succs[to]) |
3e5937d7 | 1021 | graph->succs[to] = BITMAP_ALLOC (&pta_obstack); |
c58936b6 | 1022 | bitmap_ior_into (graph->succs[to], |
57250223 | 1023 | graph->succs[from]); |
4ee00913 | 1024 | } |
4ee00913 | 1025 | |
910fdc79 DB |
1026 | clear_edges_for_node (graph, from); |
1027 | } | |
1028 | ||
3e5937d7 DB |
1029 | |
1030 | /* Add an indirect graph edge to GRAPH, going from TO to FROM if | |
1031 | it doesn't exist in the graph already. */ | |
1032 | ||
1033 | static void | |
1034 | add_implicit_graph_edge (constraint_graph_t graph, unsigned int to, | |
1035 | unsigned int from) | |
1036 | { | |
1037 | if (to == from) | |
1038 | return; | |
1039 | ||
1040 | if (!graph->implicit_preds[to]) | |
1041 | graph->implicit_preds[to] = BITMAP_ALLOC (&predbitmap_obstack); | |
1042 | ||
5f0d975b RG |
1043 | if (bitmap_set_bit (graph->implicit_preds[to], from)) |
1044 | stats.num_implicit_edges++; | |
3e5937d7 DB |
1045 | } |
1046 | ||
1047 | /* Add a predecessor graph edge to GRAPH, going from TO to FROM if | |
1048 | it doesn't exist in the graph already. | |
1049 | Return false if the edge already existed, true otherwise. */ | |
1050 | ||
1051 | static void | |
1052 | add_pred_graph_edge (constraint_graph_t graph, unsigned int to, | |
1053 | unsigned int from) | |
1054 | { | |
1055 | if (!graph->preds[to]) | |
1056 | graph->preds[to] = BITMAP_ALLOC (&predbitmap_obstack); | |
5f0d975b | 1057 | bitmap_set_bit (graph->preds[to], from); |
3e5937d7 DB |
1058 | } |
1059 | ||
1060 | /* Add a graph edge to GRAPH, going from FROM to TO if | |
910fdc79 DB |
1061 | it doesn't exist in the graph already. |
1062 | Return false if the edge already existed, true otherwise. */ | |
1063 | ||
1064 | static bool | |
57250223 DB |
1065 | add_graph_edge (constraint_graph_t graph, unsigned int to, |
1066 | unsigned int from) | |
910fdc79 | 1067 | { |
57250223 | 1068 | if (to == from) |
910fdc79 DB |
1069 | { |
1070 | return false; | |
1071 | } | |
1072 | else | |
1073 | { | |
4ee00913 | 1074 | bool r = false; |
c58936b6 | 1075 | |
57250223 | 1076 | if (!graph->succs[from]) |
3e5937d7 | 1077 | graph->succs[from] = BITMAP_ALLOC (&pta_obstack); |
5f0d975b | 1078 | if (bitmap_set_bit (graph->succs[from], to)) |
f71ef09d | 1079 | { |
57250223 | 1080 | r = true; |
3e5937d7 DB |
1081 | if (to < FIRST_REF_NODE && from < FIRST_REF_NODE) |
1082 | stats.num_edges++; | |
f71ef09d | 1083 | } |
910fdc79 DB |
1084 | return r; |
1085 | } | |
1086 | } | |
1087 | ||
1088 | ||
4ee00913 | 1089 | /* Return true if {DEST.SRC} is an existing graph edge in GRAPH. */ |
910fdc79 DB |
1090 | |
1091 | static bool | |
c58936b6 | 1092 | valid_graph_edge (constraint_graph_t graph, unsigned int src, |
4ee00913 | 1093 | unsigned int dest) |
910fdc79 | 1094 | { |
c58936b6 | 1095 | return (graph->succs[dest] |
57250223 | 1096 | && bitmap_bit_p (graph->succs[dest], src)); |
4ee00913 DB |
1097 | } |
1098 | ||
7b765bed DB |
1099 | /* Initialize the constraint graph structure to contain SIZE nodes. */ |
1100 | ||
1101 | static void | |
1102 | init_graph (unsigned int size) | |
1103 | { | |
1104 | unsigned int j; | |
1105 | ||
1106 | graph = XCNEW (struct constraint_graph); | |
1107 | graph->size = size; | |
1108 | graph->succs = XCNEWVEC (bitmap, graph->size); | |
1109 | graph->indirect_cycles = XNEWVEC (int, graph->size); | |
1110 | graph->rep = XNEWVEC (unsigned int, graph->size); | |
1111 | graph->complex = XCNEWVEC (VEC(constraint_t, heap) *, size); | |
aa46c8a3 | 1112 | graph->pe = XCNEWVEC (unsigned int, graph->size); |
7b765bed DB |
1113 | graph->pe_rep = XNEWVEC (int, graph->size); |
1114 | ||
1115 | for (j = 0; j < graph->size; j++) | |
1116 | { | |
1117 | graph->rep[j] = j; | |
7b765bed DB |
1118 | graph->pe_rep[j] = -1; |
1119 | graph->indirect_cycles[j] = -1; | |
1120 | } | |
1121 | } | |
1122 | ||
3e5937d7 | 1123 | /* Build the constraint graph, adding only predecessor edges right now. */ |
910fdc79 DB |
1124 | |
1125 | static void | |
3e5937d7 | 1126 | build_pred_graph (void) |
910fdc79 | 1127 | { |
3e5937d7 | 1128 | int i; |
910fdc79 | 1129 | constraint_t c; |
3e5937d7 | 1130 | unsigned int j; |
910fdc79 | 1131 | |
3e5937d7 DB |
1132 | graph->implicit_preds = XCNEWVEC (bitmap, graph->size); |
1133 | graph->preds = XCNEWVEC (bitmap, graph->size); | |
7b765bed DB |
1134 | graph->pointer_label = XCNEWVEC (unsigned int, graph->size); |
1135 | graph->loc_label = XCNEWVEC (unsigned int, graph->size); | |
1136 | graph->pointed_by = XCNEWVEC (bitmap, graph->size); | |
1137 | graph->points_to = XCNEWVEC (bitmap, graph->size); | |
3e5937d7 | 1138 | graph->eq_rep = XNEWVEC (int, graph->size); |
3e5937d7 | 1139 | graph->direct_nodes = sbitmap_alloc (graph->size); |
7b765bed | 1140 | graph->address_taken = BITMAP_ALLOC (&predbitmap_obstack); |
3e5937d7 DB |
1141 | sbitmap_zero (graph->direct_nodes); |
1142 | ||
1143 | for (j = 0; j < FIRST_REF_NODE; j++) | |
1144 | { | |
1145 | if (!get_varinfo (j)->is_special_var) | |
1146 | SET_BIT (graph->direct_nodes, j); | |
1147 | } | |
1148 | ||
1149 | for (j = 0; j < graph->size; j++) | |
7b765bed | 1150 | graph->eq_rep[j] = -1; |
3e5937d7 DB |
1151 | |
1152 | for (j = 0; j < VEC_length (varinfo_t, varmap); j++) | |
1153 | graph->indirect_cycles[j] = -1; | |
e8ca4159 | 1154 | |
910fdc79 DB |
1155 | for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++) |
1156 | { | |
1157 | struct constraint_expr lhs = c->lhs; | |
1158 | struct constraint_expr rhs = c->rhs; | |
5006671f RG |
1159 | unsigned int lhsvar = lhs.var; |
1160 | unsigned int rhsvar = rhs.var; | |
03190594 | 1161 | |
910fdc79 DB |
1162 | if (lhs.type == DEREF) |
1163 | { | |
3e5937d7 DB |
1164 | /* *x = y. */ |
1165 | if (rhs.offset == 0 && lhs.offset == 0 && rhs.type == SCALAR) | |
1166 | add_pred_graph_edge (graph, FIRST_REF_NODE + lhsvar, rhsvar); | |
910fdc79 DB |
1167 | } |
1168 | else if (rhs.type == DEREF) | |
1169 | { | |
3e5937d7 DB |
1170 | /* x = *y */ |
1171 | if (rhs.offset == 0 && lhs.offset == 0 && lhs.type == SCALAR) | |
1172 | add_pred_graph_edge (graph, lhsvar, FIRST_REF_NODE + rhsvar); | |
1173 | else | |
1174 | RESET_BIT (graph->direct_nodes, lhsvar); | |
910fdc79 | 1175 | } |
3e5937d7 | 1176 | else if (rhs.type == ADDRESSOF) |
910fdc79 | 1177 | { |
10bd6c5c RG |
1178 | varinfo_t v; |
1179 | ||
910fdc79 | 1180 | /* x = &y */ |
7b765bed DB |
1181 | if (graph->points_to[lhsvar] == NULL) |
1182 | graph->points_to[lhsvar] = BITMAP_ALLOC (&predbitmap_obstack); | |
1183 | bitmap_set_bit (graph->points_to[lhsvar], rhsvar); | |
1184 | ||
1185 | if (graph->pointed_by[rhsvar] == NULL) | |
1186 | graph->pointed_by[rhsvar] = BITMAP_ALLOC (&predbitmap_obstack); | |
1187 | bitmap_set_bit (graph->pointed_by[rhsvar], lhsvar); | |
1188 | ||
3e5937d7 DB |
1189 | /* Implicitly, *x = y */ |
1190 | add_implicit_graph_edge (graph, FIRST_REF_NODE + lhsvar, rhsvar); | |
1191 | ||
10bd6c5c | 1192 | /* All related variables are no longer direct nodes. */ |
3e5937d7 | 1193 | RESET_BIT (graph->direct_nodes, rhsvar); |
5006671f RG |
1194 | v = get_varinfo (rhsvar); |
1195 | if (!v->is_full_var) | |
1196 | { | |
1197 | v = lookup_vi_for_tree (v->decl); | |
1198 | do | |
1199 | { | |
1200 | RESET_BIT (graph->direct_nodes, v->id); | |
1201 | v = v->next; | |
1202 | } | |
1203 | while (v != NULL); | |
1204 | } | |
7b765bed | 1205 | bitmap_set_bit (graph->address_taken, rhsvar); |
910fdc79 | 1206 | } |
3e5937d7 DB |
1207 | else if (lhsvar > anything_id |
1208 | && lhsvar != rhsvar && lhs.offset == 0 && rhs.offset == 0) | |
910fdc79 | 1209 | { |
3e5937d7 DB |
1210 | /* x = y */ |
1211 | add_pred_graph_edge (graph, lhsvar, rhsvar); | |
1212 | /* Implicitly, *x = *y */ | |
1213 | add_implicit_graph_edge (graph, FIRST_REF_NODE + lhsvar, | |
1214 | FIRST_REF_NODE + rhsvar); | |
1215 | } | |
1216 | else if (lhs.offset != 0 || rhs.offset != 0) | |
1217 | { | |
1218 | if (rhs.offset != 0) | |
1219 | RESET_BIT (graph->direct_nodes, lhs.var); | |
7b765bed | 1220 | else if (lhs.offset != 0) |
3e5937d7 DB |
1221 | RESET_BIT (graph->direct_nodes, rhs.var); |
1222 | } | |
1223 | } | |
1224 | } | |
1225 | ||
1226 | /* Build the constraint graph, adding successor edges. */ | |
1227 | ||
1228 | static void | |
1229 | build_succ_graph (void) | |
1230 | { | |
9e39dba6 | 1231 | unsigned i, t; |
3e5937d7 DB |
1232 | constraint_t c; |
1233 | ||
1234 | for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++) | |
1235 | { | |
1236 | struct constraint_expr lhs; | |
1237 | struct constraint_expr rhs; | |
1238 | unsigned int lhsvar; | |
1239 | unsigned int rhsvar; | |
1240 | ||
1241 | if (!c) | |
1242 | continue; | |
c58936b6 | 1243 | |
3e5937d7 DB |
1244 | lhs = c->lhs; |
1245 | rhs = c->rhs; | |
5006671f RG |
1246 | lhsvar = find (lhs.var); |
1247 | rhsvar = find (rhs.var); | |
3e5937d7 DB |
1248 | |
1249 | if (lhs.type == DEREF) | |
1250 | { | |
1251 | if (rhs.offset == 0 && lhs.offset == 0 && rhs.type == SCALAR) | |
1252 | add_graph_edge (graph, FIRST_REF_NODE + lhsvar, rhsvar); | |
1253 | } | |
1254 | else if (rhs.type == DEREF) | |
1255 | { | |
1256 | if (rhs.offset == 0 && lhs.offset == 0 && lhs.type == SCALAR) | |
1257 | add_graph_edge (graph, lhsvar, FIRST_REF_NODE + rhsvar); | |
1258 | } | |
1259 | else if (rhs.type == ADDRESSOF) | |
1260 | { | |
1261 | /* x = &y */ | |
5006671f | 1262 | gcc_assert (find (rhs.var) == rhs.var); |
3e5937d7 DB |
1263 | bitmap_set_bit (get_varinfo (lhsvar)->solution, rhsvar); |
1264 | } | |
1265 | else if (lhsvar > anything_id | |
1266 | && lhsvar != rhsvar && lhs.offset == 0 && rhs.offset == 0) | |
1267 | { | |
1268 | add_graph_edge (graph, lhsvar, rhsvar); | |
910fdc79 DB |
1269 | } |
1270 | } | |
9e39dba6 | 1271 | |
de925a03 RG |
1272 | /* Add edges from STOREDANYTHING to all non-direct nodes that can |
1273 | receive pointers. */ | |
9e39dba6 RG |
1274 | t = find (storedanything_id); |
1275 | for (i = integer_id + 1; i < FIRST_REF_NODE; ++i) | |
1276 | { | |
de925a03 RG |
1277 | if (!TEST_BIT (graph->direct_nodes, i) |
1278 | && get_varinfo (i)->may_have_pointers) | |
9e39dba6 RG |
1279 | add_graph_edge (graph, find (i), t); |
1280 | } | |
379c6f48 RG |
1281 | |
1282 | /* Everything stored to ANYTHING also potentially escapes. */ | |
1283 | add_graph_edge (graph, find (escaped_id), t); | |
910fdc79 | 1284 | } |
e8ca4159 DN |
1285 | |
1286 | ||
910fdc79 DB |
1287 | /* Changed variables on the last iteration. */ |
1288 | static unsigned int changed_count; | |
1289 | static sbitmap changed; | |
1290 | ||
910fdc79 DB |
1291 | /* Strongly Connected Component visitation info. */ |
1292 | ||
1293 | struct scc_info | |
1294 | { | |
1295 | sbitmap visited; | |
7b765bed | 1296 | sbitmap deleted; |
3e5937d7 DB |
1297 | unsigned int *dfs; |
1298 | unsigned int *node_mapping; | |
910fdc79 | 1299 | int current_index; |
740e80e8 | 1300 | VEC(unsigned,heap) *scc_stack; |
910fdc79 DB |
1301 | }; |
1302 | ||
1303 | ||
1304 | /* Recursive routine to find strongly connected components in GRAPH. | |
1305 | SI is the SCC info to store the information in, and N is the id of current | |
1306 | graph node we are processing. | |
c58936b6 | 1307 | |
910fdc79 | 1308 | This is Tarjan's strongly connected component finding algorithm, as |
c58936b6 | 1309 | modified by Nuutila to keep only non-root nodes on the stack. |
910fdc79 DB |
1310 | The algorithm can be found in "On finding the strongly connected |
1311 | connected components in a directed graph" by Esko Nuutila and Eljas | |
1312 | Soisalon-Soininen, in Information Processing Letters volume 49, | |
1313 | number 1, pages 9-14. */ | |
1314 | ||
1315 | static void | |
1316 | scc_visit (constraint_graph_t graph, struct scc_info *si, unsigned int n) | |
1317 | { | |
4ee00913 DB |
1318 | unsigned int i; |
1319 | bitmap_iterator bi; | |
3e5937d7 | 1320 | unsigned int my_dfs; |
910fdc79 | 1321 | |
910fdc79 | 1322 | SET_BIT (si->visited, n); |
3e5937d7 DB |
1323 | si->dfs[n] = si->current_index ++; |
1324 | my_dfs = si->dfs[n]; | |
c58936b6 | 1325 | |
910fdc79 | 1326 | /* Visit all the successors. */ |
57250223 | 1327 | EXECUTE_IF_IN_NONNULL_BITMAP (graph->succs[n], 0, i, bi) |
910fdc79 | 1328 | { |
3e5937d7 DB |
1329 | unsigned int w; |
1330 | ||
1331 | if (i > LAST_REF_NODE) | |
1332 | break; | |
1333 | ||
1334 | w = find (i); | |
7b765bed | 1335 | if (TEST_BIT (si->deleted, w)) |
3e5937d7 DB |
1336 | continue; |
1337 | ||
4ee00913 DB |
1338 | if (!TEST_BIT (si->visited, w)) |
1339 | scc_visit (graph, si, w); | |
3e5937d7 DB |
1340 | { |
1341 | unsigned int t = find (w); | |
1342 | unsigned int nnode = find (n); | |
62e5bf5d | 1343 | gcc_assert (nnode == n); |
3e5937d7 DB |
1344 | |
1345 | if (si->dfs[t] < si->dfs[nnode]) | |
1346 | si->dfs[n] = si->dfs[t]; | |
1347 | } | |
910fdc79 | 1348 | } |
c58936b6 | 1349 | |
910fdc79 | 1350 | /* See if any components have been identified. */ |
3e5937d7 | 1351 | if (si->dfs[n] == my_dfs) |
910fdc79 | 1352 | { |
3e5937d7 DB |
1353 | if (VEC_length (unsigned, si->scc_stack) > 0 |
1354 | && si->dfs[VEC_last (unsigned, si->scc_stack)] >= my_dfs) | |
910fdc79 | 1355 | { |
3e5937d7 DB |
1356 | bitmap scc = BITMAP_ALLOC (NULL); |
1357 | bool have_ref_node = n >= FIRST_REF_NODE; | |
1358 | unsigned int lowest_node; | |
1359 | bitmap_iterator bi; | |
910fdc79 | 1360 | |
3e5937d7 | 1361 | bitmap_set_bit (scc, n); |
910fdc79 | 1362 | |
3e5937d7 DB |
1363 | while (VEC_length (unsigned, si->scc_stack) != 0 |
1364 | && si->dfs[VEC_last (unsigned, si->scc_stack)] >= my_dfs) | |
1365 | { | |
1366 | unsigned int w = VEC_pop (unsigned, si->scc_stack); | |
910fdc79 | 1367 | |
3e5937d7 DB |
1368 | bitmap_set_bit (scc, w); |
1369 | if (w >= FIRST_REF_NODE) | |
1370 | have_ref_node = true; | |
1371 | } | |
4ee00913 | 1372 | |
3e5937d7 DB |
1373 | lowest_node = bitmap_first_set_bit (scc); |
1374 | gcc_assert (lowest_node < FIRST_REF_NODE); | |
7b765bed DB |
1375 | |
1376 | /* Collapse the SCC nodes into a single node, and mark the | |
1377 | indirect cycles. */ | |
3e5937d7 DB |
1378 | EXECUTE_IF_SET_IN_BITMAP (scc, 0, i, bi) |
1379 | { | |
1380 | if (i < FIRST_REF_NODE) | |
1381 | { | |
3e5937d7 DB |
1382 | if (unite (lowest_node, i)) |
1383 | unify_nodes (graph, lowest_node, i, false); | |
1384 | } | |
1385 | else | |
1386 | { | |
1387 | unite (lowest_node, i); | |
1388 | graph->indirect_cycles[i - FIRST_REF_NODE] = lowest_node; | |
1389 | } | |
1390 | } | |
4ee00913 | 1391 | } |
7b765bed | 1392 | SET_BIT (si->deleted, n); |
910fdc79 | 1393 | } |
3e5937d7 DB |
1394 | else |
1395 | VEC_safe_push (unsigned, heap, si->scc_stack, n); | |
910fdc79 DB |
1396 | } |
1397 | ||
3e5937d7 DB |
1398 | /* Unify node FROM into node TO, updating the changed count if |
1399 | necessary when UPDATE_CHANGED is true. */ | |
910fdc79 DB |
1400 | |
1401 | static void | |
3e5937d7 DB |
1402 | unify_nodes (constraint_graph_t graph, unsigned int to, unsigned int from, |
1403 | bool update_changed) | |
910fdc79 | 1404 | { |
910fdc79 | 1405 | |
3e5937d7 DB |
1406 | gcc_assert (to != from && find (to) == to); |
1407 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1408 | fprintf (dump_file, "Unifying %s to %s\n", | |
1409 | get_varinfo (from)->name, | |
1410 | get_varinfo (to)->name); | |
910fdc79 | 1411 | |
3e5937d7 DB |
1412 | if (update_changed) |
1413 | stats.unified_vars_dynamic++; | |
1414 | else | |
1415 | stats.unified_vars_static++; | |
910fdc79 | 1416 | |
3e5937d7 DB |
1417 | merge_graph_nodes (graph, to, from); |
1418 | merge_node_constraints (graph, to, from); | |
c58936b6 | 1419 | |
7b765bed DB |
1420 | /* Mark TO as changed if FROM was changed. If TO was already marked |
1421 | as changed, decrease the changed count. */ | |
1422 | ||
3e5937d7 | 1423 | if (update_changed && TEST_BIT (changed, from)) |
910fdc79 | 1424 | { |
3e5937d7 DB |
1425 | RESET_BIT (changed, from); |
1426 | if (!TEST_BIT (changed, to)) | |
1427 | SET_BIT (changed, to); | |
910fdc79 | 1428 | else |
3e5937d7 DB |
1429 | { |
1430 | gcc_assert (changed_count > 0); | |
1431 | changed_count--; | |
1432 | } | |
1433 | } | |
aa46c8a3 | 1434 | if (get_varinfo (from)->solution) |
3e5937d7 | 1435 | { |
aa46c8a3 DB |
1436 | /* If the solution changes because of the merging, we need to mark |
1437 | the variable as changed. */ | |
1438 | if (bitmap_ior_into (get_varinfo (to)->solution, | |
1439 | get_varinfo (from)->solution)) | |
910fdc79 | 1440 | { |
aa46c8a3 DB |
1441 | if (update_changed && !TEST_BIT (changed, to)) |
1442 | { | |
1443 | SET_BIT (changed, to); | |
1444 | changed_count++; | |
1445 | } | |
1446 | } | |
b8698a0f | 1447 | |
aa46c8a3 DB |
1448 | BITMAP_FREE (get_varinfo (from)->solution); |
1449 | BITMAP_FREE (get_varinfo (from)->oldsolution); | |
b8698a0f | 1450 | |
aa46c8a3 DB |
1451 | if (stats.iterations > 0) |
1452 | { | |
1453 | BITMAP_FREE (get_varinfo (to)->oldsolution); | |
1454 | get_varinfo (to)->oldsolution = BITMAP_ALLOC (&oldpta_obstack); | |
910fdc79 | 1455 | } |
3e5937d7 | 1456 | } |
3e5937d7 DB |
1457 | if (valid_graph_edge (graph, to, to)) |
1458 | { | |
1459 | if (graph->succs[to]) | |
1460 | bitmap_clear_bit (graph->succs[to], to); | |
910fdc79 | 1461 | } |
910fdc79 DB |
1462 | } |
1463 | ||
910fdc79 DB |
1464 | /* Information needed to compute the topological ordering of a graph. */ |
1465 | ||
1466 | struct topo_info | |
1467 | { | |
1468 | /* sbitmap of visited nodes. */ | |
1469 | sbitmap visited; | |
1470 | /* Array that stores the topological order of the graph, *in | |
1471 | reverse*. */ | |
740e80e8 | 1472 | VEC(unsigned,heap) *topo_order; |
910fdc79 DB |
1473 | }; |
1474 | ||
1475 | ||
1476 | /* Initialize and return a topological info structure. */ | |
1477 | ||
1478 | static struct topo_info * | |
1479 | init_topo_info (void) | |
1480 | { | |
7b765bed | 1481 | size_t size = graph->size; |
5ed6ace5 | 1482 | struct topo_info *ti = XNEW (struct topo_info); |
910fdc79 DB |
1483 | ti->visited = sbitmap_alloc (size); |
1484 | sbitmap_zero (ti->visited); | |
740e80e8 | 1485 | ti->topo_order = VEC_alloc (unsigned, heap, 1); |
910fdc79 DB |
1486 | return ti; |
1487 | } | |
1488 | ||
1489 | ||
1490 | /* Free the topological sort info pointed to by TI. */ | |
1491 | ||
1492 | static void | |
1493 | free_topo_info (struct topo_info *ti) | |
1494 | { | |
1495 | sbitmap_free (ti->visited); | |
740e80e8 | 1496 | VEC_free (unsigned, heap, ti->topo_order); |
910fdc79 DB |
1497 | free (ti); |
1498 | } | |
1499 | ||
1500 | /* Visit the graph in topological order, and store the order in the | |
1501 | topo_info structure. */ | |
1502 | ||
1503 | static void | |
1504 | topo_visit (constraint_graph_t graph, struct topo_info *ti, | |
1505 | unsigned int n) | |
1506 | { | |
4ee00913 | 1507 | bitmap_iterator bi; |
4ee00913 DB |
1508 | unsigned int j; |
1509 | ||
910fdc79 | 1510 | SET_BIT (ti->visited, n); |
4ee00913 | 1511 | |
3e5937d7 DB |
1512 | if (graph->succs[n]) |
1513 | EXECUTE_IF_SET_IN_BITMAP (graph->succs[n], 0, j, bi) | |
4ee00913 DB |
1514 | { |
1515 | if (!TEST_BIT (ti->visited, j)) | |
1516 | topo_visit (graph, ti, j); | |
1517 | } | |
3e5937d7 | 1518 | |
740e80e8 | 1519 | VEC_safe_push (unsigned, heap, ti->topo_order, n); |
910fdc79 DB |
1520 | } |
1521 | ||
5006671f RG |
1522 | /* Process a constraint C that represents x = *(y + off), using DELTA as the |
1523 | starting solution for y. */ | |
910fdc79 DB |
1524 | |
1525 | static void | |
1526 | do_sd_constraint (constraint_graph_t graph, constraint_t c, | |
1527 | bitmap delta) | |
1528 | { | |
7b765bed | 1529 | unsigned int lhs = c->lhs.var; |
910fdc79 DB |
1530 | bool flag = false; |
1531 | bitmap sol = get_varinfo (lhs)->solution; | |
1532 | unsigned int j; | |
1533 | bitmap_iterator bi; | |
5006671f | 1534 | HOST_WIDE_INT roffset = c->rhs.offset; |
4ee00913 | 1535 | |
5006671f RG |
1536 | /* Our IL does not allow this. */ |
1537 | gcc_assert (c->lhs.offset == 0); | |
0e1f4c6b | 1538 | |
5006671f RG |
1539 | /* If the solution of Y contains anything it is good enough to transfer |
1540 | this to the LHS. */ | |
14c28276 RG |
1541 | if (bitmap_bit_p (delta, anything_id)) |
1542 | { | |
1543 | flag |= bitmap_set_bit (sol, anything_id); | |
1544 | goto done; | |
1545 | } | |
1546 | ||
5006671f RG |
1547 | /* If we do not know at with offset the rhs is dereferenced compute |
1548 | the reachability set of DELTA, conservatively assuming it is | |
1549 | dereferenced at all valid offsets. */ | |
1550 | if (roffset == UNKNOWN_OFFSET) | |
1551 | { | |
1552 | solution_set_expand (delta, delta); | |
1553 | /* No further offset processing is necessary. */ | |
1554 | roffset = 0; | |
1555 | } | |
1556 | ||
c58936b6 | 1557 | /* For each variable j in delta (Sol(y)), add |
910fdc79 DB |
1558 | an edge in the graph from j to x, and union Sol(j) into Sol(x). */ |
1559 | EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi) | |
1560 | { | |
5006671f RG |
1561 | varinfo_t v = get_varinfo (j); |
1562 | HOST_WIDE_INT fieldoffset = v->offset + roffset; | |
1563 | unsigned int t; | |
1564 | ||
1565 | if (v->is_full_var) | |
1566 | fieldoffset = v->offset; | |
1567 | else if (roffset != 0) | |
1568 | v = first_vi_for_offset (v, fieldoffset); | |
1569 | /* If the access is outside of the variable we can ignore it. */ | |
1570 | if (!v) | |
1571 | continue; | |
910fdc79 | 1572 | |
5006671f RG |
1573 | do |
1574 | { | |
3e5937d7 | 1575 | t = find (v->id); |
4ee00913 DB |
1576 | |
1577 | /* Adding edges from the special vars is pointless. | |
1578 | They don't have sets that can change. */ | |
b7091901 | 1579 | if (get_varinfo (t)->is_special_var) |
4ee00913 | 1580 | flag |= bitmap_ior_into (sol, get_varinfo (t)->solution); |
b7091901 | 1581 | /* Merging the solution from ESCAPED needlessly increases |
472c7fbd | 1582 | the set. Use ESCAPED as representative instead. */ |
5006671f | 1583 | else if (v->id == escaped_id) |
6a66f28e | 1584 | flag |= bitmap_set_bit (sol, escaped_id); |
57250223 | 1585 | else if (add_graph_edge (graph, lhs, t)) |
4ee00913 | 1586 | flag |= bitmap_ior_into (sol, get_varinfo (t)->solution); |
5006671f RG |
1587 | |
1588 | /* If the variable is not exactly at the requested offset | |
1589 | we have to include the next one. */ | |
1590 | if (v->offset == (unsigned HOST_WIDE_INT)fieldoffset | |
1591 | || v->next == NULL) | |
1592 | break; | |
1593 | ||
1594 | v = v->next; | |
1595 | fieldoffset = v->offset; | |
910fdc79 | 1596 | } |
5006671f | 1597 | while (1); |
910fdc79 | 1598 | } |
4cf4d6a3 | 1599 | |
4ee00913 | 1600 | done: |
910fdc79 DB |
1601 | /* If the LHS solution changed, mark the var as changed. */ |
1602 | if (flag) | |
1603 | { | |
1604 | get_varinfo (lhs)->solution = sol; | |
1605 | if (!TEST_BIT (changed, lhs)) | |
1606 | { | |
1607 | SET_BIT (changed, lhs); | |
1608 | changed_count++; | |
1609 | } | |
c58936b6 | 1610 | } |
910fdc79 DB |
1611 | } |
1612 | ||
5006671f RG |
1613 | /* Process a constraint C that represents *(x + off) = y using DELTA |
1614 | as the starting solution for x. */ | |
910fdc79 DB |
1615 | |
1616 | static void | |
57250223 | 1617 | do_ds_constraint (constraint_t c, bitmap delta) |
910fdc79 | 1618 | { |
7b765bed | 1619 | unsigned int rhs = c->rhs.var; |
910fdc79 DB |
1620 | bitmap sol = get_varinfo (rhs)->solution; |
1621 | unsigned int j; | |
1622 | bitmap_iterator bi; | |
5006671f | 1623 | HOST_WIDE_INT loff = c->lhs.offset; |
910fdc79 | 1624 | |
9e39dba6 RG |
1625 | /* Our IL does not allow this. */ |
1626 | gcc_assert (c->rhs.offset == 0); | |
1627 | ||
1628 | /* If the solution of y contains ANYTHING simply use the ANYTHING | |
1629 | solution. This avoids needlessly increasing the points-to sets. */ | |
1630 | if (bitmap_bit_p (sol, anything_id)) | |
1631 | sol = get_varinfo (find (anything_id))->solution; | |
1632 | ||
1633 | /* If the solution for x contains ANYTHING we have to merge the | |
1634 | solution of y into all pointer variables which we do via | |
1635 | STOREDANYTHING. */ | |
1636 | if (bitmap_bit_p (delta, anything_id)) | |
1637 | { | |
1638 | unsigned t = find (storedanything_id); | |
1639 | if (add_graph_edge (graph, t, rhs)) | |
1640 | { | |
1641 | if (bitmap_ior_into (get_varinfo (t)->solution, sol)) | |
1642 | { | |
1643 | if (!TEST_BIT (changed, t)) | |
1644 | { | |
1645 | SET_BIT (changed, t); | |
1646 | changed_count++; | |
1647 | } | |
1648 | } | |
1649 | } | |
1650 | return; | |
1651 | } | |
4ee00913 | 1652 | |
5006671f RG |
1653 | /* If we do not know at with offset the rhs is dereferenced compute |
1654 | the reachability set of DELTA, conservatively assuming it is | |
1655 | dereferenced at all valid offsets. */ | |
1656 | if (loff == UNKNOWN_OFFSET) | |
1657 | { | |
1658 | solution_set_expand (delta, delta); | |
1659 | loff = 0; | |
1660 | } | |
1661 | ||
910fdc79 DB |
1662 | /* For each member j of delta (Sol(x)), add an edge from y to j and |
1663 | union Sol(y) into Sol(j) */ | |
1664 | EXECUTE_IF_SET_IN_BITMAP (delta, 0, j, bi) | |
1665 | { | |
5006671f RG |
1666 | varinfo_t v = get_varinfo (j); |
1667 | unsigned int t; | |
1668 | HOST_WIDE_INT fieldoffset = v->offset + loff; | |
c58936b6 | 1669 | |
46aaa417 RG |
1670 | /* If v is a global variable then this is an escape point. */ |
1671 | if (v->is_global_var) | |
de70bb20 RG |
1672 | { |
1673 | t = find (escaped_id); | |
1674 | if (add_graph_edge (graph, t, rhs) | |
1675 | && bitmap_ior_into (get_varinfo (t)->solution, sol) | |
1676 | && !TEST_BIT (changed, t)) | |
1677 | { | |
1678 | SET_BIT (changed, t); | |
1679 | changed_count++; | |
1680 | } | |
1681 | } | |
1682 | ||
5006671f RG |
1683 | if (v->is_special_var) |
1684 | continue; | |
1685 | ||
1686 | if (v->is_full_var) | |
1687 | fieldoffset = v->offset; | |
1688 | else if (loff != 0) | |
1689 | v = first_vi_for_offset (v, fieldoffset); | |
1690 | /* If the access is outside of the variable we can ignore it. */ | |
1691 | if (!v) | |
1692 | continue; | |
57250223 | 1693 | |
5006671f RG |
1694 | do |
1695 | { | |
9e39dba6 | 1696 | if (v->may_have_pointers) |
910fdc79 | 1697 | { |
9e39dba6 | 1698 | t = find (v->id); |
de70bb20 RG |
1699 | if (add_graph_edge (graph, t, rhs) |
1700 | && bitmap_ior_into (get_varinfo (t)->solution, sol) | |
1701 | && !TEST_BIT (changed, t)) | |
910fdc79 | 1702 | { |
de70bb20 RG |
1703 | SET_BIT (changed, t); |
1704 | changed_count++; | |
1705 | } | |
1706 | } | |
5006671f RG |
1707 | |
1708 | /* If the variable is not exactly at the requested offset | |
1709 | we have to include the next one. */ | |
1710 | if (v->offset == (unsigned HOST_WIDE_INT)fieldoffset | |
1711 | || v->next == NULL) | |
1712 | break; | |
1713 | ||
1714 | v = v->next; | |
1715 | fieldoffset = v->offset; | |
57250223 | 1716 | } |
5006671f | 1717 | while (1); |
910fdc79 DB |
1718 | } |
1719 | } | |
1720 | ||
3e5937d7 DB |
1721 | /* Handle a non-simple (simple meaning requires no iteration), |
1722 | constraint (IE *x = &y, x = *y, *x = y, and x = y with offsets involved). */ | |
c58936b6 | 1723 | |
910fdc79 DB |
1724 | static void |
1725 | do_complex_constraint (constraint_graph_t graph, constraint_t c, bitmap delta) | |
1726 | { | |
1727 | if (c->lhs.type == DEREF) | |
1728 | { | |
1729 | if (c->rhs.type == ADDRESSOF) | |
1730 | { | |
7b765bed | 1731 | gcc_unreachable(); |
910fdc79 DB |
1732 | } |
1733 | else | |
1734 | { | |
1735 | /* *x = y */ | |
57250223 | 1736 | do_ds_constraint (c, delta); |
910fdc79 DB |
1737 | } |
1738 | } | |
57250223 | 1739 | else if (c->rhs.type == DEREF) |
910fdc79 DB |
1740 | { |
1741 | /* x = *y */ | |
13c2c08b DB |
1742 | if (!(get_varinfo (c->lhs.var)->is_special_var)) |
1743 | do_sd_constraint (graph, c, delta); | |
910fdc79 | 1744 | } |
c58936b6 | 1745 | else |
57250223 | 1746 | { |
c58936b6 | 1747 | bitmap tmp; |
57250223 DB |
1748 | bitmap solution; |
1749 | bool flag = false; | |
57250223 | 1750 | |
62e5bf5d | 1751 | gcc_assert (c->rhs.type == SCALAR && c->lhs.type == SCALAR); |
7b765bed DB |
1752 | solution = get_varinfo (c->rhs.var)->solution; |
1753 | tmp = get_varinfo (c->lhs.var)->solution; | |
57250223 DB |
1754 | |
1755 | flag = set_union_with_increment (tmp, solution, c->rhs.offset); | |
c58936b6 | 1756 | |
57250223 DB |
1757 | if (flag) |
1758 | { | |
7b765bed DB |
1759 | get_varinfo (c->lhs.var)->solution = tmp; |
1760 | if (!TEST_BIT (changed, c->lhs.var)) | |
57250223 | 1761 | { |
7b765bed | 1762 | SET_BIT (changed, c->lhs.var); |
57250223 DB |
1763 | changed_count++; |
1764 | } | |
1765 | } | |
1766 | } | |
910fdc79 DB |
1767 | } |
1768 | ||
1769 | /* Initialize and return a new SCC info structure. */ | |
1770 | ||
1771 | static struct scc_info * | |
3e5937d7 | 1772 | init_scc_info (size_t size) |
910fdc79 | 1773 | { |
5ed6ace5 | 1774 | struct scc_info *si = XNEW (struct scc_info); |
3e5937d7 | 1775 | size_t i; |
910fdc79 DB |
1776 | |
1777 | si->current_index = 0; | |
1778 | si->visited = sbitmap_alloc (size); | |
1779 | sbitmap_zero (si->visited); | |
7b765bed DB |
1780 | si->deleted = sbitmap_alloc (size); |
1781 | sbitmap_zero (si->deleted); | |
3e5937d7 DB |
1782 | si->node_mapping = XNEWVEC (unsigned int, size); |
1783 | si->dfs = XCNEWVEC (unsigned int, size); | |
1784 | ||
1785 | for (i = 0; i < size; i++) | |
1786 | si->node_mapping[i] = i; | |
1787 | ||
740e80e8 | 1788 | si->scc_stack = VEC_alloc (unsigned, heap, 1); |
910fdc79 DB |
1789 | return si; |
1790 | } | |
1791 | ||
1792 | /* Free an SCC info structure pointed to by SI */ | |
1793 | ||
1794 | static void | |
1795 | free_scc_info (struct scc_info *si) | |
c58936b6 | 1796 | { |
910fdc79 | 1797 | sbitmap_free (si->visited); |
7b765bed | 1798 | sbitmap_free (si->deleted); |
3e5937d7 DB |
1799 | free (si->node_mapping); |
1800 | free (si->dfs); | |
740e80e8 | 1801 | VEC_free (unsigned, heap, si->scc_stack); |
3e5937d7 | 1802 | free (si); |
910fdc79 DB |
1803 | } |
1804 | ||
1805 | ||
3e5937d7 DB |
1806 | /* Find indirect cycles in GRAPH that occur, using strongly connected |
1807 | components, and note them in the indirect cycles map. | |
1808 | ||
1809 | This technique comes from Ben Hardekopf and Calvin Lin, | |
1810 | "It Pays to be Lazy: Fast and Accurate Pointer Analysis for Millions of | |
1811 | Lines of Code", submitted to PLDI 2007. */ | |
910fdc79 DB |
1812 | |
1813 | static void | |
3e5937d7 | 1814 | find_indirect_cycles (constraint_graph_t graph) |
910fdc79 DB |
1815 | { |
1816 | unsigned int i; | |
3e5937d7 DB |
1817 | unsigned int size = graph->size; |
1818 | struct scc_info *si = init_scc_info (size); | |
910fdc79 | 1819 | |
3e5937d7 DB |
1820 | for (i = 0; i < MIN (LAST_REF_NODE, size); i ++ ) |
1821 | if (!TEST_BIT (si->visited, i) && find (i) == i) | |
910fdc79 | 1822 | scc_visit (graph, si, i); |
c58936b6 | 1823 | |
910fdc79 DB |
1824 | free_scc_info (si); |
1825 | } | |
1826 | ||
1827 | /* Compute a topological ordering for GRAPH, and store the result in the | |
1828 | topo_info structure TI. */ | |
1829 | ||
c58936b6 | 1830 | static void |
910fdc79 DB |
1831 | compute_topo_order (constraint_graph_t graph, |
1832 | struct topo_info *ti) | |
1833 | { | |
1834 | unsigned int i; | |
7b765bed | 1835 | unsigned int size = graph->size; |
c58936b6 | 1836 | |
910fdc79 | 1837 | for (i = 0; i != size; ++i) |
3e5937d7 | 1838 | if (!TEST_BIT (ti->visited, i) && find (i) == i) |
910fdc79 DB |
1839 | topo_visit (graph, ti, i); |
1840 | } | |
1841 | ||
7b765bed DB |
1842 | /* Structure used to for hash value numbering of pointer equivalence |
1843 | classes. */ | |
1844 | ||
1845 | typedef struct equiv_class_label | |
1846 | { | |
3691626c | 1847 | hashval_t hashcode; |
7b765bed DB |
1848 | unsigned int equivalence_class; |
1849 | bitmap labels; | |
7b765bed | 1850 | } *equiv_class_label_t; |
586de218 | 1851 | typedef const struct equiv_class_label *const_equiv_class_label_t; |
7b765bed DB |
1852 | |
1853 | /* A hashtable for mapping a bitmap of labels->pointer equivalence | |
1854 | classes. */ | |
1855 | static htab_t pointer_equiv_class_table; | |
1856 | ||
1857 | /* A hashtable for mapping a bitmap of labels->location equivalence | |
1858 | classes. */ | |
1859 | static htab_t location_equiv_class_table; | |
1860 | ||
1861 | /* Hash function for a equiv_class_label_t */ | |
1862 | ||
1863 | static hashval_t | |
1864 | equiv_class_label_hash (const void *p) | |
1865 | { | |
586de218 | 1866 | const_equiv_class_label_t const ecl = (const_equiv_class_label_t) p; |
7b765bed DB |
1867 | return ecl->hashcode; |
1868 | } | |
1869 | ||
1870 | /* Equality function for two equiv_class_label_t's. */ | |
1871 | ||
1872 | static int | |
1873 | equiv_class_label_eq (const void *p1, const void *p2) | |
1874 | { | |
586de218 KG |
1875 | const_equiv_class_label_t const eql1 = (const_equiv_class_label_t) p1; |
1876 | const_equiv_class_label_t const eql2 = (const_equiv_class_label_t) p2; | |
821bb7f8 RG |
1877 | return (eql1->hashcode == eql2->hashcode |
1878 | && bitmap_equal_p (eql1->labels, eql2->labels)); | |
7b765bed DB |
1879 | } |
1880 | ||
1881 | /* Lookup a equivalence class in TABLE by the bitmap of LABELS it | |
1882 | contains. */ | |
1883 | ||
1884 | static unsigned int | |
1885 | equiv_class_lookup (htab_t table, bitmap labels) | |
1886 | { | |
1887 | void **slot; | |
1888 | struct equiv_class_label ecl; | |
1889 | ||
1890 | ecl.labels = labels; | |
1891 | ecl.hashcode = bitmap_hash (labels); | |
c58936b6 | 1892 | |
7b765bed DB |
1893 | slot = htab_find_slot_with_hash (table, &ecl, |
1894 | ecl.hashcode, NO_INSERT); | |
1895 | if (!slot) | |
1896 | return 0; | |
1897 | else | |
1898 | return ((equiv_class_label_t) *slot)->equivalence_class; | |
1899 | } | |
1900 | ||
1901 | ||
1902 | /* Add an equivalence class named EQUIVALENCE_CLASS with labels LABELS | |
1903 | to TABLE. */ | |
1904 | ||
1905 | static void | |
1906 | equiv_class_add (htab_t table, unsigned int equivalence_class, | |
1907 | bitmap labels) | |
1908 | { | |
1909 | void **slot; | |
1910 | equiv_class_label_t ecl = XNEW (struct equiv_class_label); | |
1911 | ||
1912 | ecl->labels = labels; | |
1913 | ecl->equivalence_class = equivalence_class; | |
1914 | ecl->hashcode = bitmap_hash (labels); | |
1915 | ||
1916 | slot = htab_find_slot_with_hash (table, ecl, | |
1917 | ecl->hashcode, INSERT); | |
1918 | gcc_assert (!*slot); | |
1919 | *slot = (void *) ecl; | |
1920 | } | |
1921 | ||
1922 | /* Perform offline variable substitution. | |
910fdc79 | 1923 | |
7b765bed DB |
1924 | This is a worst case quadratic time way of identifying variables |
1925 | that must have equivalent points-to sets, including those caused by | |
1926 | static cycles, and single entry subgraphs, in the constraint graph. | |
3e5937d7 | 1927 | |
7b765bed DB |
1928 | The technique is described in "Exploiting Pointer and Location |
1929 | Equivalence to Optimize Pointer Analysis. In the 14th International | |
1930 | Static Analysis Symposium (SAS), August 2007." It is known as the | |
1931 | "HU" algorithm, and is equivalent to value numbering the collapsed | |
1932 | constraint graph including evaluating unions. | |
3e5937d7 DB |
1933 | |
1934 | The general method of finding equivalence classes is as follows: | |
1935 | Add fake nodes (REF nodes) and edges for *a = b and a = *b constraints. | |
7b765bed DB |
1936 | Initialize all non-REF nodes to be direct nodes. |
1937 | For each constraint a = a U {b}, we set pts(a) = pts(a) u {fresh | |
1938 | variable} | |
1939 | For each constraint containing the dereference, we also do the same | |
1940 | thing. | |
1941 | ||
1942 | We then compute SCC's in the graph and unify nodes in the same SCC, | |
1943 | including pts sets. | |
1944 | ||
1945 | For each non-collapsed node x: | |
1946 | Visit all unvisited explicit incoming edges. | |
1947 | Ignoring all non-pointers, set pts(x) = Union of pts(a) for y | |
1948 | where y->x. | |
1949 | Lookup the equivalence class for pts(x). | |
1950 | If we found one, equivalence_class(x) = found class. | |
1951 | Otherwise, equivalence_class(x) = new class, and new_class is | |
1952 | added to the lookup table. | |
3e5937d7 DB |
1953 | |
1954 | All direct nodes with the same equivalence class can be replaced | |
1955 | with a single representative node. | |
1956 | All unlabeled nodes (label == 0) are not pointers and all edges | |
1957 | involving them can be eliminated. | |
7b765bed DB |
1958 | We perform these optimizations during rewrite_constraints |
1959 | ||
1960 | In addition to pointer equivalence class finding, we also perform | |
1961 | location equivalence class finding. This is the set of variables | |
1962 | that always appear together in points-to sets. We use this to | |
1963 | compress the size of the points-to sets. */ | |
1964 | ||
1965 | /* Current maximum pointer equivalence class id. */ | |
1966 | static int pointer_equiv_class; | |
3e5937d7 | 1967 | |
7b765bed DB |
1968 | /* Current maximum location equivalence class id. */ |
1969 | static int location_equiv_class; | |
3e5937d7 DB |
1970 | |
1971 | /* Recursive routine to find strongly connected components in GRAPH, | |
7b765bed | 1972 | and label it's nodes with DFS numbers. */ |
910fdc79 DB |
1973 | |
1974 | static void | |
7b765bed | 1975 | condense_visit (constraint_graph_t graph, struct scc_info *si, unsigned int n) |
910fdc79 | 1976 | { |
3e5937d7 DB |
1977 | unsigned int i; |
1978 | bitmap_iterator bi; | |
1979 | unsigned int my_dfs; | |
c58936b6 | 1980 | |
3e5937d7 DB |
1981 | gcc_assert (si->node_mapping[n] == n); |
1982 | SET_BIT (si->visited, n); | |
1983 | si->dfs[n] = si->current_index ++; | |
1984 | my_dfs = si->dfs[n]; | |
c58936b6 | 1985 | |
3e5937d7 DB |
1986 | /* Visit all the successors. */ |
1987 | EXECUTE_IF_IN_NONNULL_BITMAP (graph->preds[n], 0, i, bi) | |
910fdc79 | 1988 | { |
3e5937d7 | 1989 | unsigned int w = si->node_mapping[i]; |
910fdc79 | 1990 | |
7b765bed | 1991 | if (TEST_BIT (si->deleted, w)) |
910fdc79 DB |
1992 | continue; |
1993 | ||
3e5937d7 | 1994 | if (!TEST_BIT (si->visited, w)) |
7b765bed | 1995 | condense_visit (graph, si, w); |
3e5937d7 DB |
1996 | { |
1997 | unsigned int t = si->node_mapping[w]; | |
1998 | unsigned int nnode = si->node_mapping[n]; | |
62e5bf5d | 1999 | gcc_assert (nnode == n); |
910fdc79 | 2000 | |
3e5937d7 DB |
2001 | if (si->dfs[t] < si->dfs[nnode]) |
2002 | si->dfs[n] = si->dfs[t]; | |
2003 | } | |
2004 | } | |
910fdc79 | 2005 | |
3e5937d7 DB |
2006 | /* Visit all the implicit predecessors. */ |
2007 | EXECUTE_IF_IN_NONNULL_BITMAP (graph->implicit_preds[n], 0, i, bi) | |
2008 | { | |
2009 | unsigned int w = si->node_mapping[i]; | |
2010 | ||
7b765bed | 2011 | if (TEST_BIT (si->deleted, w)) |
3e5937d7 DB |
2012 | continue; |
2013 | ||
2014 | if (!TEST_BIT (si->visited, w)) | |
7b765bed | 2015 | condense_visit (graph, si, w); |
3e5937d7 DB |
2016 | { |
2017 | unsigned int t = si->node_mapping[w]; | |
2018 | unsigned int nnode = si->node_mapping[n]; | |
2019 | gcc_assert (nnode == n); | |
2020 | ||
2021 | if (si->dfs[t] < si->dfs[nnode]) | |
2022 | si->dfs[n] = si->dfs[t]; | |
2023 | } | |
2024 | } | |
4ee00913 | 2025 | |
3e5937d7 DB |
2026 | /* See if any components have been identified. */ |
2027 | if (si->dfs[n] == my_dfs) | |
2028 | { | |
2029 | while (VEC_length (unsigned, si->scc_stack) != 0 | |
2030 | && si->dfs[VEC_last (unsigned, si->scc_stack)] >= my_dfs) | |
910fdc79 | 2031 | { |
3e5937d7 DB |
2032 | unsigned int w = VEC_pop (unsigned, si->scc_stack); |
2033 | si->node_mapping[w] = n; | |
2034 | ||
2035 | if (!TEST_BIT (graph->direct_nodes, w)) | |
2036 | RESET_BIT (graph->direct_nodes, n); | |
3e5937d7 | 2037 | |
7b765bed DB |
2038 | /* Unify our nodes. */ |
2039 | if (graph->preds[w]) | |
2040 | { | |
2041 | if (!graph->preds[n]) | |
2042 | graph->preds[n] = BITMAP_ALLOC (&predbitmap_obstack); | |
2043 | bitmap_ior_into (graph->preds[n], graph->preds[w]); | |
2044 | } | |
2045 | if (graph->implicit_preds[w]) | |
2046 | { | |
2047 | if (!graph->implicit_preds[n]) | |
2048 | graph->implicit_preds[n] = BITMAP_ALLOC (&predbitmap_obstack); | |
2049 | bitmap_ior_into (graph->implicit_preds[n], | |
2050 | graph->implicit_preds[w]); | |
2051 | } | |
2052 | if (graph->points_to[w]) | |
2053 | { | |
2054 | if (!graph->points_to[n]) | |
2055 | graph->points_to[n] = BITMAP_ALLOC (&predbitmap_obstack); | |
2056 | bitmap_ior_into (graph->points_to[n], | |
2057 | graph->points_to[w]); | |
2058 | } | |
3e5937d7 | 2059 | } |
7b765bed | 2060 | SET_BIT (si->deleted, n); |
3e5937d7 DB |
2061 | } |
2062 | else | |
2063 | VEC_safe_push (unsigned, heap, si->scc_stack, n); | |
2064 | } | |
2065 | ||
7b765bed DB |
2066 | /* Label pointer equivalences. */ |
2067 | ||
2068 | static void | |
2069 | label_visit (constraint_graph_t graph, struct scc_info *si, unsigned int n) | |
2070 | { | |
2071 | unsigned int i; | |
2072 | bitmap_iterator bi; | |
2073 | SET_BIT (si->visited, n); | |
2074 | ||
2075 | if (!graph->points_to[n]) | |
2076 | graph->points_to[n] = BITMAP_ALLOC (&predbitmap_obstack); | |
2077 | ||
2078 | /* Label and union our incoming edges's points to sets. */ | |
2079 | EXECUTE_IF_IN_NONNULL_BITMAP (graph->preds[n], 0, i, bi) | |
2080 | { | |
2081 | unsigned int w = si->node_mapping[i]; | |
2082 | if (!TEST_BIT (si->visited, w)) | |
2083 | label_visit (graph, si, w); | |
2084 | ||
2085 | /* Skip unused edges */ | |
2086 | if (w == n || graph->pointer_label[w] == 0) | |
3dc21182 DB |
2087 | continue; |
2088 | ||
7b765bed DB |
2089 | if (graph->points_to[w]) |
2090 | bitmap_ior_into(graph->points_to[n], graph->points_to[w]); | |
7b765bed DB |
2091 | } |
2092 | /* Indirect nodes get fresh variables. */ | |
2093 | if (!TEST_BIT (graph->direct_nodes, n)) | |
2094 | bitmap_set_bit (graph->points_to[n], FIRST_REF_NODE + n); | |
2095 | ||
2096 | if (!bitmap_empty_p (graph->points_to[n])) | |
2097 | { | |
2098 | unsigned int label = equiv_class_lookup (pointer_equiv_class_table, | |
2099 | graph->points_to[n]); | |
2100 | if (!label) | |
2101 | { | |
7b765bed DB |
2102 | label = pointer_equiv_class++; |
2103 | equiv_class_add (pointer_equiv_class_table, | |
2104 | label, graph->points_to[n]); | |
2105 | } | |
2106 | graph->pointer_label[n] = label; | |
2107 | } | |
2108 | } | |
2109 | ||
3e5937d7 DB |
2110 | /* Perform offline variable substitution, discovering equivalence |
2111 | classes, and eliminating non-pointer variables. */ | |
2112 | ||
2113 | static struct scc_info * | |
2114 | perform_var_substitution (constraint_graph_t graph) | |
2115 | { | |
2116 | unsigned int i; | |
2117 | unsigned int size = graph->size; | |
2118 | struct scc_info *si = init_scc_info (size); | |
2119 | ||
2120 | bitmap_obstack_initialize (&iteration_obstack); | |
7b765bed DB |
2121 | pointer_equiv_class_table = htab_create (511, equiv_class_label_hash, |
2122 | equiv_class_label_eq, free); | |
2123 | location_equiv_class_table = htab_create (511, equiv_class_label_hash, | |
2124 | equiv_class_label_eq, free); | |
2125 | pointer_equiv_class = 1; | |
2126 | location_equiv_class = 1; | |
2127 | ||
2128 | /* Condense the nodes, which means to find SCC's, count incoming | |
2129 | predecessors, and unite nodes in SCC's. */ | |
aa46c8a3 | 2130 | for (i = 0; i < FIRST_REF_NODE; i++) |
7b765bed DB |
2131 | if (!TEST_BIT (si->visited, si->node_mapping[i])) |
2132 | condense_visit (graph, si, si->node_mapping[i]); | |
3e5937d7 | 2133 | |
7b765bed DB |
2134 | sbitmap_zero (si->visited); |
2135 | /* Actually the label the nodes for pointer equivalences */ | |
aa46c8a3 | 2136 | for (i = 0; i < FIRST_REF_NODE; i++) |
3e5937d7 DB |
2137 | if (!TEST_BIT (si->visited, si->node_mapping[i])) |
2138 | label_visit (graph, si, si->node_mapping[i]); | |
2139 | ||
7b765bed DB |
2140 | /* Calculate location equivalence labels. */ |
2141 | for (i = 0; i < FIRST_REF_NODE; i++) | |
2142 | { | |
2143 | bitmap pointed_by; | |
2144 | bitmap_iterator bi; | |
2145 | unsigned int j; | |
2146 | unsigned int label; | |
2147 | ||
2148 | if (!graph->pointed_by[i]) | |
2149 | continue; | |
2150 | pointed_by = BITMAP_ALLOC (&iteration_obstack); | |
2151 | ||
2152 | /* Translate the pointed-by mapping for pointer equivalence | |
2153 | labels. */ | |
2154 | EXECUTE_IF_SET_IN_BITMAP (graph->pointed_by[i], 0, j, bi) | |
2155 | { | |
2156 | bitmap_set_bit (pointed_by, | |
2157 | graph->pointer_label[si->node_mapping[j]]); | |
2158 | } | |
2159 | /* The original pointed_by is now dead. */ | |
2160 | BITMAP_FREE (graph->pointed_by[i]); | |
2161 | ||
2162 | /* Look up the location equivalence label if one exists, or make | |
2163 | one otherwise. */ | |
2164 | label = equiv_class_lookup (location_equiv_class_table, | |
2165 | pointed_by); | |
2166 | if (label == 0) | |
2167 | { | |
2168 | label = location_equiv_class++; | |
2169 | equiv_class_add (location_equiv_class_table, | |
2170 | label, pointed_by); | |
2171 | } | |
2172 | else | |
2173 | { | |
2174 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2175 | fprintf (dump_file, "Found location equivalence for node %s\n", | |
2176 | get_varinfo (i)->name); | |
2177 | BITMAP_FREE (pointed_by); | |
2178 | } | |
2179 | graph->loc_label[i] = label; | |
2180 | ||
2181 | } | |
2182 | ||
3e5937d7 DB |
2183 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2184 | for (i = 0; i < FIRST_REF_NODE; i++) | |
2185 | { | |
2186 | bool direct_node = TEST_BIT (graph->direct_nodes, i); | |
2187 | fprintf (dump_file, | |
7b765bed DB |
2188 | "Equivalence classes for %s node id %d:%s are pointer: %d" |
2189 | ", location:%d\n", | |
3e5937d7 | 2190 | direct_node ? "Direct node" : "Indirect node", i, |
62e5bf5d | 2191 | get_varinfo (i)->name, |
7b765bed DB |
2192 | graph->pointer_label[si->node_mapping[i]], |
2193 | graph->loc_label[si->node_mapping[i]]); | |
3e5937d7 DB |
2194 | } |
2195 | ||
2196 | /* Quickly eliminate our non-pointer variables. */ | |
2197 | ||
2198 | for (i = 0; i < FIRST_REF_NODE; i++) | |
2199 | { | |
2200 | unsigned int node = si->node_mapping[i]; | |
2201 | ||
aa46c8a3 | 2202 | if (graph->pointer_label[node] == 0) |
3e5937d7 | 2203 | { |
23e73993 | 2204 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3e5937d7 DB |
2205 | fprintf (dump_file, |
2206 | "%s is a non-pointer variable, eliminating edges.\n", | |
2207 | get_varinfo (node)->name); | |
2208 | stats.nonpointer_vars++; | |
2209 | clear_edges_for_node (graph, node); | |
910fdc79 DB |
2210 | } |
2211 | } | |
7b765bed | 2212 | |
3e5937d7 DB |
2213 | return si; |
2214 | } | |
2215 | ||
2216 | /* Free information that was only necessary for variable | |
2217 | substitution. */ | |
910fdc79 | 2218 | |
3e5937d7 DB |
2219 | static void |
2220 | free_var_substitution_info (struct scc_info *si) | |
2221 | { | |
2222 | free_scc_info (si); | |
7b765bed DB |
2223 | free (graph->pointer_label); |
2224 | free (graph->loc_label); | |
2225 | free (graph->pointed_by); | |
2226 | free (graph->points_to); | |
3e5937d7 DB |
2227 | free (graph->eq_rep); |
2228 | sbitmap_free (graph->direct_nodes); | |
7b765bed DB |
2229 | htab_delete (pointer_equiv_class_table); |
2230 | htab_delete (location_equiv_class_table); | |
4ee00913 | 2231 | bitmap_obstack_release (&iteration_obstack); |
3e5937d7 DB |
2232 | } |
2233 | ||
2234 | /* Return an existing node that is equivalent to NODE, which has | |
2235 | equivalence class LABEL, if one exists. Return NODE otherwise. */ | |
2236 | ||
2237 | static unsigned int | |
2238 | find_equivalent_node (constraint_graph_t graph, | |
2239 | unsigned int node, unsigned int label) | |
2240 | { | |
2241 | /* If the address version of this variable is unused, we can | |
2242 | substitute it for anything else with the same label. | |
2243 | Otherwise, we know the pointers are equivalent, but not the | |
7b765bed | 2244 | locations, and we can unite them later. */ |
3e5937d7 | 2245 | |
7b765bed | 2246 | if (!bitmap_bit_p (graph->address_taken, node)) |
3e5937d7 DB |
2247 | { |
2248 | gcc_assert (label < graph->size); | |
2249 | ||
2250 | if (graph->eq_rep[label] != -1) | |
2251 | { | |
2252 | /* Unify the two variables since we know they are equivalent. */ | |
2253 | if (unite (graph->eq_rep[label], node)) | |
2254 | unify_nodes (graph, graph->eq_rep[label], node, false); | |
2255 | return graph->eq_rep[label]; | |
2256 | } | |
2257 | else | |
2258 | { | |
2259 | graph->eq_rep[label] = node; | |
7b765bed | 2260 | graph->pe_rep[label] = node; |
3e5937d7 DB |
2261 | } |
2262 | } | |
7b765bed DB |
2263 | else |
2264 | { | |
2265 | gcc_assert (label < graph->size); | |
2266 | graph->pe[node] = label; | |
2267 | if (graph->pe_rep[label] == -1) | |
2268 | graph->pe_rep[label] = node; | |
2269 | } | |
2270 | ||
3e5937d7 DB |
2271 | return node; |
2272 | } | |
2273 | ||
7b765bed DB |
2274 | /* Unite pointer equivalent but not location equivalent nodes in |
2275 | GRAPH. This may only be performed once variable substitution is | |
2276 | finished. */ | |
2277 | ||
2278 | static void | |
2279 | unite_pointer_equivalences (constraint_graph_t graph) | |
2280 | { | |
2281 | unsigned int i; | |
2282 | ||
2283 | /* Go through the pointer equivalences and unite them to their | |
2284 | representative, if they aren't already. */ | |
aa46c8a3 | 2285 | for (i = 0; i < FIRST_REF_NODE; i++) |
7b765bed DB |
2286 | { |
2287 | unsigned int label = graph->pe[i]; | |
aa46c8a3 DB |
2288 | if (label) |
2289 | { | |
2290 | int label_rep = graph->pe_rep[label]; | |
b8698a0f | 2291 | |
aa46c8a3 DB |
2292 | if (label_rep == -1) |
2293 | continue; | |
b8698a0f | 2294 | |
aa46c8a3 DB |
2295 | label_rep = find (label_rep); |
2296 | if (label_rep >= 0 && unite (label_rep, find (i))) | |
2297 | unify_nodes (graph, label_rep, i, false); | |
2298 | } | |
7b765bed DB |
2299 | } |
2300 | } | |
2301 | ||
2302 | /* Move complex constraints to the GRAPH nodes they belong to. */ | |
3e5937d7 DB |
2303 | |
2304 | static void | |
7b765bed DB |
2305 | move_complex_constraints (constraint_graph_t graph) |
2306 | { | |
2307 | int i; | |
2308 | constraint_t c; | |
2309 | ||
2310 | for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++) | |
2311 | { | |
2312 | if (c) | |
2313 | { | |
2314 | struct constraint_expr lhs = c->lhs; | |
2315 | struct constraint_expr rhs = c->rhs; | |
2316 | ||
2317 | if (lhs.type == DEREF) | |
2318 | { | |
2319 | insert_into_complex (graph, lhs.var, c); | |
2320 | } | |
2321 | else if (rhs.type == DEREF) | |
2322 | { | |
2323 | if (!(get_varinfo (lhs.var)->is_special_var)) | |
2324 | insert_into_complex (graph, rhs.var, c); | |
2325 | } | |
2326 | else if (rhs.type != ADDRESSOF && lhs.var > anything_id | |
2327 | && (lhs.offset != 0 || rhs.offset != 0)) | |
2328 | { | |
2329 | insert_into_complex (graph, rhs.var, c); | |
2330 | } | |
2331 | } | |
2332 | } | |
2333 | } | |
2334 | ||
2335 | ||
2336 | /* Optimize and rewrite complex constraints while performing | |
2337 | collapsing of equivalent nodes. SI is the SCC_INFO that is the | |
2338 | result of perform_variable_substitution. */ | |
2339 | ||
2340 | static void | |
2341 | rewrite_constraints (constraint_graph_t graph, | |
2342 | struct scc_info *si) | |
3e5937d7 DB |
2343 | { |
2344 | int i; | |
2345 | unsigned int j; | |
2346 | constraint_t c; | |
2347 | ||
2348 | for (j = 0; j < graph->size; j++) | |
2349 | gcc_assert (find (j) == j); | |
2350 | ||
2351 | for (i = 0; VEC_iterate (constraint_t, constraints, i, c); i++) | |
2352 | { | |
2353 | struct constraint_expr lhs = c->lhs; | |
2354 | struct constraint_expr rhs = c->rhs; | |
5006671f RG |
2355 | unsigned int lhsvar = find (lhs.var); |
2356 | unsigned int rhsvar = find (rhs.var); | |
3e5937d7 DB |
2357 | unsigned int lhsnode, rhsnode; |
2358 | unsigned int lhslabel, rhslabel; | |
2359 | ||
2360 | lhsnode = si->node_mapping[lhsvar]; | |
2361 | rhsnode = si->node_mapping[rhsvar]; | |
7b765bed DB |
2362 | lhslabel = graph->pointer_label[lhsnode]; |
2363 | rhslabel = graph->pointer_label[rhsnode]; | |
3e5937d7 DB |
2364 | |
2365 | /* See if it is really a non-pointer variable, and if so, ignore | |
2366 | the constraint. */ | |
2367 | if (lhslabel == 0) | |
2368 | { | |
aa46c8a3 | 2369 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3e5937d7 | 2370 | { |
b8698a0f | 2371 | |
aa46c8a3 DB |
2372 | fprintf (dump_file, "%s is a non-pointer variable," |
2373 | "ignoring constraint:", | |
2374 | get_varinfo (lhs.var)->name); | |
2375 | dump_constraint (dump_file, c); | |
3e5937d7 | 2376 | } |
aa46c8a3 DB |
2377 | VEC_replace (constraint_t, constraints, i, NULL); |
2378 | continue; | |
3e5937d7 DB |
2379 | } |
2380 | ||
2381 | if (rhslabel == 0) | |
2382 | { | |
aa46c8a3 | 2383 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3e5937d7 | 2384 | { |
b8698a0f | 2385 | |
aa46c8a3 DB |
2386 | fprintf (dump_file, "%s is a non-pointer variable," |
2387 | "ignoring constraint:", | |
2388 | get_varinfo (rhs.var)->name); | |
2389 | dump_constraint (dump_file, c); | |
3e5937d7 | 2390 | } |
aa46c8a3 DB |
2391 | VEC_replace (constraint_t, constraints, i, NULL); |
2392 | continue; | |
3e5937d7 DB |
2393 | } |
2394 | ||
2395 | lhsvar = find_equivalent_node (graph, lhsvar, lhslabel); | |
2396 | rhsvar = find_equivalent_node (graph, rhsvar, rhslabel); | |
2397 | c->lhs.var = lhsvar; | |
2398 | c->rhs.var = rhsvar; | |
2399 | ||
3e5937d7 DB |
2400 | } |
2401 | } | |
2402 | ||
2403 | /* Eliminate indirect cycles involving NODE. Return true if NODE was | |
2404 | part of an SCC, false otherwise. */ | |
2405 | ||
2406 | static bool | |
2407 | eliminate_indirect_cycles (unsigned int node) | |
2408 | { | |
2409 | if (graph->indirect_cycles[node] != -1 | |
2410 | && !bitmap_empty_p (get_varinfo (node)->solution)) | |
2411 | { | |
2412 | unsigned int i; | |
2413 | VEC(unsigned,heap) *queue = NULL; | |
2414 | int queuepos; | |
2415 | unsigned int to = find (graph->indirect_cycles[node]); | |
2416 | bitmap_iterator bi; | |
2417 | ||
2418 | /* We can't touch the solution set and call unify_nodes | |
2419 | at the same time, because unify_nodes is going to do | |
2420 | bitmap unions into it. */ | |
2421 | ||
2422 | EXECUTE_IF_SET_IN_BITMAP (get_varinfo (node)->solution, 0, i, bi) | |
2423 | { | |
2424 | if (find (i) == i && i != to) | |
2425 | { | |
2426 | if (unite (to, i)) | |
2427 | VEC_safe_push (unsigned, heap, queue, i); | |
2428 | } | |
2429 | } | |
2430 | ||
2431 | for (queuepos = 0; | |
2432 | VEC_iterate (unsigned, queue, queuepos, i); | |
2433 | queuepos++) | |
2434 | { | |
2435 | unify_nodes (graph, to, i, true); | |
2436 | } | |
2437 | VEC_free (unsigned, heap, queue); | |
2438 | return true; | |
2439 | } | |
2440 | return false; | |
910fdc79 DB |
2441 | } |
2442 | ||
910fdc79 DB |
2443 | /* Solve the constraint graph GRAPH using our worklist solver. |
2444 | This is based on the PW* family of solvers from the "Efficient Field | |
2445 | Sensitive Pointer Analysis for C" paper. | |
2446 | It works by iterating over all the graph nodes, processing the complex | |
2447 | constraints and propagating the copy constraints, until everything stops | |
2448 | changed. This corresponds to steps 6-8 in the solving list given above. */ | |
2449 | ||
2450 | static void | |
2451 | solve_graph (constraint_graph_t graph) | |
2452 | { | |
7b765bed | 2453 | unsigned int size = graph->size; |
910fdc79 | 2454 | unsigned int i; |
3e5937d7 | 2455 | bitmap pts; |
910fdc79 | 2456 | |
3e5937d7 | 2457 | changed_count = 0; |
910fdc79 | 2458 | changed = sbitmap_alloc (size); |
3e5937d7 | 2459 | sbitmap_zero (changed); |
c58936b6 | 2460 | |
3e5937d7 | 2461 | /* Mark all initial non-collapsed nodes as changed. */ |
910fdc79 | 2462 | for (i = 0; i < size; i++) |
3e5937d7 DB |
2463 | { |
2464 | varinfo_t ivi = get_varinfo (i); | |
2465 | if (find (i) == i && !bitmap_empty_p (ivi->solution) | |
2466 | && ((graph->succs[i] && !bitmap_empty_p (graph->succs[i])) | |
2467 | || VEC_length (constraint_t, graph->complex[i]) > 0)) | |
2468 | { | |
2469 | SET_BIT (changed, i); | |
2470 | changed_count++; | |
2471 | } | |
2472 | } | |
2473 | ||
2474 | /* Allocate a bitmap to be used to store the changed bits. */ | |
2475 | pts = BITMAP_ALLOC (&pta_obstack); | |
c58936b6 | 2476 | |
910fdc79 DB |
2477 | while (changed_count > 0) |
2478 | { | |
2479 | unsigned int i; | |
2480 | struct topo_info *ti = init_topo_info (); | |
2481 | stats.iterations++; | |
4ee00913 | 2482 | |
910fdc79 | 2483 | bitmap_obstack_initialize (&iteration_obstack); |
c58936b6 | 2484 | |
910fdc79 DB |
2485 | compute_topo_order (graph, ti); |
2486 | ||
740e80e8 | 2487 | while (VEC_length (unsigned, ti->topo_order) != 0) |
910fdc79 | 2488 | { |
3e5937d7 | 2489 | |
740e80e8 | 2490 | i = VEC_pop (unsigned, ti->topo_order); |
3e5937d7 DB |
2491 | |
2492 | /* If this variable is not a representative, skip it. */ | |
2493 | if (find (i) != i) | |
2494 | continue; | |
2495 | ||
d3c36974 DB |
2496 | /* In certain indirect cycle cases, we may merge this |
2497 | variable to another. */ | |
62e5bf5d | 2498 | if (eliminate_indirect_cycles (i) && find (i) != i) |
d3c36974 | 2499 | continue; |
910fdc79 DB |
2500 | |
2501 | /* If the node has changed, we need to process the | |
2502 | complex constraints and outgoing edges again. */ | |
2503 | if (TEST_BIT (changed, i)) | |
2504 | { | |
2505 | unsigned int j; | |
2506 | constraint_t c; | |
910fdc79 | 2507 | bitmap solution; |
3e5937d7 | 2508 | VEC(constraint_t,heap) *complex = graph->complex[i]; |
21392f19 | 2509 | bool solution_empty; |
48e540b0 | 2510 | |
910fdc79 DB |
2511 | RESET_BIT (changed, i); |
2512 | changed_count--; | |
2513 | ||
3e5937d7 DB |
2514 | /* Compute the changed set of solution bits. */ |
2515 | bitmap_and_compl (pts, get_varinfo (i)->solution, | |
2516 | get_varinfo (i)->oldsolution); | |
2517 | ||
2518 | if (bitmap_empty_p (pts)) | |
2519 | continue; | |
2520 | ||
2521 | bitmap_ior_into (get_varinfo (i)->oldsolution, pts); | |
2522 | ||
910fdc79 | 2523 | solution = get_varinfo (i)->solution; |
21392f19 DB |
2524 | solution_empty = bitmap_empty_p (solution); |
2525 | ||
2526 | /* Process the complex constraints */ | |
910fdc79 | 2527 | for (j = 0; VEC_iterate (constraint_t, complex, j, c); j++) |
21392f19 | 2528 | { |
7b765bed DB |
2529 | /* XXX: This is going to unsort the constraints in |
2530 | some cases, which will occasionally add duplicate | |
2531 | constraints during unification. This does not | |
2532 | affect correctness. */ | |
2533 | c->lhs.var = find (c->lhs.var); | |
2534 | c->rhs.var = find (c->rhs.var); | |
2535 | ||
21392f19 DB |
2536 | /* The only complex constraint that can change our |
2537 | solution to non-empty, given an empty solution, | |
2538 | is a constraint where the lhs side is receiving | |
2539 | some set from elsewhere. */ | |
2540 | if (!solution_empty || c->lhs.type != DEREF) | |
3e5937d7 | 2541 | do_complex_constraint (graph, c, pts); |
21392f19 | 2542 | } |
910fdc79 | 2543 | |
21392f19 DB |
2544 | solution_empty = bitmap_empty_p (solution); |
2545 | ||
5006671f | 2546 | if (!solution_empty) |
4ee00913 | 2547 | { |
3e5937d7 | 2548 | bitmap_iterator bi; |
5006671f | 2549 | unsigned eff_escaped_id = find (escaped_id); |
3e5937d7 | 2550 | |
21392f19 | 2551 | /* Propagate solution to all successors. */ |
c58936b6 | 2552 | EXECUTE_IF_IN_NONNULL_BITMAP (graph->succs[i], |
21392f19 | 2553 | 0, j, bi) |
4ee00913 | 2554 | { |
3e5937d7 DB |
2555 | bitmap tmp; |
2556 | bool flag; | |
2557 | ||
2558 | unsigned int to = find (j); | |
2559 | tmp = get_varinfo (to)->solution; | |
2560 | flag = false; | |
c58936b6 | 2561 | |
3e5937d7 DB |
2562 | /* Don't try to propagate to ourselves. */ |
2563 | if (to == i) | |
2564 | continue; | |
c58936b6 | 2565 | |
5006671f RG |
2566 | /* If we propagate from ESCAPED use ESCAPED as |
2567 | placeholder. */ | |
2568 | if (i == eff_escaped_id) | |
2569 | flag = bitmap_set_bit (tmp, escaped_id); | |
2570 | else | |
2571 | flag = set_union_with_increment (tmp, pts, 0); | |
c58936b6 | 2572 | |
21392f19 | 2573 | if (flag) |
4ee00913 | 2574 | { |
3e5937d7 DB |
2575 | get_varinfo (to)->solution = tmp; |
2576 | if (!TEST_BIT (changed, to)) | |
21392f19 | 2577 | { |
3e5937d7 | 2578 | SET_BIT (changed, to); |
21392f19 DB |
2579 | changed_count++; |
2580 | } | |
4ee00913 DB |
2581 | } |
2582 | } | |
910fdc79 DB |
2583 | } |
2584 | } | |
2585 | } | |
2586 | free_topo_info (ti); | |
2587 | bitmap_obstack_release (&iteration_obstack); | |
2588 | } | |
c58936b6 | 2589 | |
3e5937d7 | 2590 | BITMAP_FREE (pts); |
910fdc79 | 2591 | sbitmap_free (changed); |
3e5937d7 | 2592 | bitmap_obstack_release (&oldpta_obstack); |
910fdc79 DB |
2593 | } |
2594 | ||
3e5937d7 | 2595 | /* Map from trees to variable infos. */ |
15814ba0 | 2596 | static struct pointer_map_t *vi_for_tree; |
910fdc79 | 2597 | |
910fdc79 | 2598 | |
15814ba0 | 2599 | /* Insert ID as the variable id for tree T in the vi_for_tree map. */ |
910fdc79 | 2600 | |
c58936b6 | 2601 | static void |
3e5937d7 | 2602 | insert_vi_for_tree (tree t, varinfo_t vi) |
910fdc79 | 2603 | { |
15814ba0 PB |
2604 | void **slot = pointer_map_insert (vi_for_tree, t); |
2605 | gcc_assert (vi); | |
910fdc79 | 2606 | gcc_assert (*slot == NULL); |
15814ba0 | 2607 | *slot = vi; |
910fdc79 DB |
2608 | } |
2609 | ||
3e5937d7 | 2610 | /* Find the variable info for tree T in VI_FOR_TREE. If T does not |
15814ba0 | 2611 | exist in the map, return NULL, otherwise, return the varinfo we found. */ |
910fdc79 | 2612 | |
15814ba0 PB |
2613 | static varinfo_t |
2614 | lookup_vi_for_tree (tree t) | |
910fdc79 | 2615 | { |
15814ba0 PB |
2616 | void **slot = pointer_map_contains (vi_for_tree, t); |
2617 | if (slot == NULL) | |
2618 | return NULL; | |
910fdc79 | 2619 | |
15814ba0 | 2620 | return (varinfo_t) *slot; |
910fdc79 DB |
2621 | } |
2622 | ||
2623 | /* Return a printable name for DECL */ | |
2624 | ||
2625 | static const char * | |
2626 | alias_get_name (tree decl) | |
2627 | { | |
2628 | const char *res = get_name (decl); | |
2629 | char *temp; | |
2630 | int num_printed = 0; | |
2631 | ||
2632 | if (res != NULL) | |
2633 | return res; | |
2634 | ||
2635 | res = "NULL"; | |
4f6c9110 RG |
2636 | if (!dump_file) |
2637 | return res; | |
2638 | ||
910fdc79 DB |
2639 | if (TREE_CODE (decl) == SSA_NAME) |
2640 | { | |
c58936b6 | 2641 | num_printed = asprintf (&temp, "%s_%u", |
910fdc79 DB |
2642 | alias_get_name (SSA_NAME_VAR (decl)), |
2643 | SSA_NAME_VERSION (decl)); | |
2644 | } | |
2645 | else if (DECL_P (decl)) | |
2646 | { | |
2647 | num_printed = asprintf (&temp, "D.%u", DECL_UID (decl)); | |
2648 | } | |
2649 | if (num_printed > 0) | |
2650 | { | |
2651 | res = ggc_strdup (temp); | |
2652 | free (temp); | |
2653 | } | |
2654 | return res; | |
2655 | } | |
2656 | ||
15814ba0 PB |
2657 | /* Find the variable id for tree T in the map. |
2658 | If T doesn't exist in the map, create an entry for it and return it. */ | |
910fdc79 | 2659 | |
3e5937d7 DB |
2660 | static varinfo_t |
2661 | get_vi_for_tree (tree t) | |
910fdc79 | 2662 | { |
15814ba0 PB |
2663 | void **slot = pointer_map_contains (vi_for_tree, t); |
2664 | if (slot == NULL) | |
3e5937d7 | 2665 | return get_varinfo (create_variable_info_for (t, alias_get_name (t))); |
c58936b6 | 2666 | |
15814ba0 | 2667 | return (varinfo_t) *slot; |
910fdc79 DB |
2668 | } |
2669 | ||
b14e9388 | 2670 | /* Get a scalar constraint expression for a new temporary variable. */ |
910fdc79 DB |
2671 | |
2672 | static struct constraint_expr | |
b14e9388 | 2673 | new_scalar_tmp_constraint_exp (const char *name) |
910fdc79 | 2674 | { |
b14e9388 | 2675 | struct constraint_expr tmp; |
b14e9388 | 2676 | varinfo_t vi; |
910fdc79 | 2677 | |
0bbf2ffa | 2678 | vi = new_var_info (NULL_TREE, name); |
b14e9388 RG |
2679 | vi->offset = 0; |
2680 | vi->size = -1; | |
2681 | vi->fullsize = -1; | |
2682 | vi->is_full_var = 1; | |
c0d459f0 | 2683 | |
b14e9388 RG |
2684 | tmp.var = vi->id; |
2685 | tmp.type = SCALAR; | |
2686 | tmp.offset = 0; | |
c0d459f0 | 2687 | |
b14e9388 | 2688 | return tmp; |
c0d459f0 RG |
2689 | } |
2690 | ||
2691 | /* Get a constraint expression vector from an SSA_VAR_P node. | |
2692 | If address_p is true, the result will be taken its address of. */ | |
2693 | ||
2694 | static void | |
2695 | get_constraint_for_ssa_var (tree t, VEC(ce_s, heap) **results, bool address_p) | |
2696 | { | |
2697 | struct constraint_expr cexpr; | |
2698 | varinfo_t vi; | |
2699 | ||
2700 | /* We allow FUNCTION_DECLs here even though it doesn't make much sense. */ | |
910fdc79 DB |
2701 | gcc_assert (SSA_VAR_P (t) || DECL_P (t)); |
2702 | ||
2703 | /* For parameters, get at the points-to set for the actual parm | |
2704 | decl. */ | |
c58936b6 DB |
2705 | if (TREE_CODE (t) == SSA_NAME |
2706 | && TREE_CODE (SSA_NAME_VAR (t)) == PARM_DECL | |
38635499 | 2707 | && SSA_NAME_IS_DEFAULT_DEF (t)) |
c0d459f0 RG |
2708 | { |
2709 | get_constraint_for_ssa_var (SSA_NAME_VAR (t), results, address_p); | |
2710 | return; | |
2711 | } | |
910fdc79 | 2712 | |
c0d459f0 RG |
2713 | vi = get_vi_for_tree (t); |
2714 | cexpr.var = vi->id; | |
910fdc79 | 2715 | cexpr.type = SCALAR; |
c0d459f0 | 2716 | cexpr.offset = 0; |
47bcb538 DB |
2717 | /* If we determine the result is "anything", and we know this is readonly, |
2718 | say it points to readonly memory instead. */ | |
2719 | if (cexpr.var == anything_id && TREE_READONLY (t)) | |
910fdc79 | 2720 | { |
c0d459f0 | 2721 | gcc_unreachable (); |
3e5937d7 | 2722 | cexpr.type = ADDRESSOF; |
910fdc79 DB |
2723 | cexpr.var = readonly_id; |
2724 | } | |
c58936b6 | 2725 | |
c0d459f0 RG |
2726 | /* If we are not taking the address of the constraint expr, add all |
2727 | sub-fiels of the variable as well. */ | |
de925a03 RG |
2728 | if (!address_p |
2729 | && !vi->is_full_var) | |
c0d459f0 RG |
2730 | { |
2731 | for (; vi; vi = vi->next) | |
2732 | { | |
2733 | cexpr.var = vi->id; | |
2734 | VEC_safe_push (ce_s, heap, *results, &cexpr); | |
2735 | } | |
2736 | return; | |
2737 | } | |
2738 | ||
2739 | VEC_safe_push (ce_s, heap, *results, &cexpr); | |
910fdc79 DB |
2740 | } |
2741 | ||
faf2ecc5 RG |
2742 | /* Process constraint T, performing various simplifications and then |
2743 | adding it to our list of overall constraints. */ | |
910fdc79 DB |
2744 | |
2745 | static void | |
faf2ecc5 | 2746 | process_constraint (constraint_t t) |
910fdc79 DB |
2747 | { |
2748 | struct constraint_expr rhs = t->rhs; | |
2749 | struct constraint_expr lhs = t->lhs; | |
c58936b6 | 2750 | |
910fdc79 DB |
2751 | gcc_assert (rhs.var < VEC_length (varinfo_t, varmap)); |
2752 | gcc_assert (lhs.var < VEC_length (varinfo_t, varmap)); | |
2753 | ||
5006671f RG |
2754 | /* If we didn't get any useful constraint from the lhs we get |
2755 | &ANYTHING as fallback from get_constraint_for. Deal with | |
2756 | it here by turning it into *ANYTHING. */ | |
2757 | if (lhs.type == ADDRESSOF | |
2758 | && lhs.var == anything_id) | |
2759 | lhs.type = DEREF; | |
2760 | ||
2761 | /* ADDRESSOF on the lhs is invalid. */ | |
2762 | gcc_assert (lhs.type != ADDRESSOF); | |
910fdc79 | 2763 | |
910fdc79 | 2764 | /* This can happen in our IR with things like n->a = *p */ |
5006671f | 2765 | if (rhs.type == DEREF && lhs.type == DEREF && rhs.var != anything_id) |
910fdc79 DB |
2766 | { |
2767 | /* Split into tmp = *rhs, *lhs = tmp */ | |
b14e9388 RG |
2768 | struct constraint_expr tmplhs; |
2769 | tmplhs = new_scalar_tmp_constraint_exp ("doubledereftmp"); | |
faf2ecc5 RG |
2770 | process_constraint (new_constraint (tmplhs, rhs)); |
2771 | process_constraint (new_constraint (lhs, tmplhs)); | |
7b765bed DB |
2772 | } |
2773 | else if (rhs.type == ADDRESSOF && lhs.type == DEREF) | |
2774 | { | |
2775 | /* Split into tmp = &rhs, *lhs = tmp */ | |
b14e9388 RG |
2776 | struct constraint_expr tmplhs; |
2777 | tmplhs = new_scalar_tmp_constraint_exp ("derefaddrtmp"); | |
faf2ecc5 RG |
2778 | process_constraint (new_constraint (tmplhs, rhs)); |
2779 | process_constraint (new_constraint (lhs, tmplhs)); | |
910fdc79 | 2780 | } |
910fdc79 DB |
2781 | else |
2782 | { | |
3e5937d7 | 2783 | gcc_assert (rhs.type != ADDRESSOF || rhs.offset == 0); |
b5efa470 | 2784 | VEC_safe_push (constraint_t, heap, constraints, t); |
910fdc79 DB |
2785 | } |
2786 | } | |
2787 | ||
9e39dba6 RG |
2788 | /* Return true if T is a type that could contain pointers. */ |
2789 | ||
2790 | static bool | |
2791 | type_could_have_pointers (tree type) | |
2792 | { | |
2793 | if (POINTER_TYPE_P (type)) | |
2794 | return true; | |
2795 | ||
2796 | if (TREE_CODE (type) == ARRAY_TYPE) | |
2797 | return type_could_have_pointers (TREE_TYPE (type)); | |
2798 | ||
2799 | return AGGREGATE_TYPE_P (type); | |
2800 | } | |
2801 | ||
21392f19 DB |
2802 | /* Return true if T is a variable of a type that could contain |
2803 | pointers. */ | |
2804 | ||
2805 | static bool | |
2806 | could_have_pointers (tree t) | |
2807 | { | |
9e39dba6 | 2808 | return type_could_have_pointers (TREE_TYPE (t)); |
21392f19 | 2809 | } |
910fdc79 DB |
2810 | |
2811 | /* Return the position, in bits, of FIELD_DECL from the beginning of its | |
2812 | structure. */ | |
2813 | ||
ee7d4b57 | 2814 | static HOST_WIDE_INT |
910fdc79 DB |
2815 | bitpos_of_field (const tree fdecl) |
2816 | { | |
2817 | ||
ee7d4b57 RG |
2818 | if (!host_integerp (DECL_FIELD_OFFSET (fdecl), 0) |
2819 | || !host_integerp (DECL_FIELD_BIT_OFFSET (fdecl), 0)) | |
910fdc79 | 2820 | return -1; |
c58936b6 | 2821 | |
ee7d4b57 RG |
2822 | return (TREE_INT_CST_LOW (DECL_FIELD_OFFSET (fdecl)) * 8 |
2823 | + TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (fdecl))); | |
910fdc79 DB |
2824 | } |
2825 | ||
2826 | ||
e5bae89b RG |
2827 | /* Get constraint expressions for offsetting PTR by OFFSET. Stores the |
2828 | resulting constraint expressions in *RESULTS. */ | |
2829 | ||
2830 | static void | |
2831 | get_constraint_for_ptr_offset (tree ptr, tree offset, | |
2832 | VEC (ce_s, heap) **results) | |
2833 | { | |
bd02b3a0 | 2834 | struct constraint_expr c; |
e5bae89b | 2835 | unsigned int j, n; |
5006671f | 2836 | HOST_WIDE_INT rhsunitoffset, rhsoffset; |
e5bae89b RG |
2837 | |
2838 | /* If we do not do field-sensitive PTA adding offsets to pointers | |
2839 | does not change the points-to solution. */ | |
2840 | if (!use_field_sensitive) | |
2841 | { | |
2842 | get_constraint_for (ptr, results); | |
2843 | return; | |
2844 | } | |
2845 | ||
2846 | /* If the offset is not a non-negative integer constant that fits | |
2847 | in a HOST_WIDE_INT, we have to fall back to a conservative | |
2848 | solution which includes all sub-fields of all pointed-to | |
5006671f | 2849 | variables of ptr. */ |
779704e7 RG |
2850 | if (offset == NULL_TREE |
2851 | || !host_integerp (offset, 0)) | |
5006671f RG |
2852 | rhsoffset = UNKNOWN_OFFSET; |
2853 | else | |
e5bae89b | 2854 | { |
5006671f RG |
2855 | /* Make sure the bit-offset also fits. */ |
2856 | rhsunitoffset = TREE_INT_CST_LOW (offset); | |
2857 | rhsoffset = rhsunitoffset * BITS_PER_UNIT; | |
2858 | if (rhsunitoffset != rhsoffset / BITS_PER_UNIT) | |
2859 | rhsoffset = UNKNOWN_OFFSET; | |
e5bae89b RG |
2860 | } |
2861 | ||
2862 | get_constraint_for (ptr, results); | |
2863 | if (rhsoffset == 0) | |
2864 | return; | |
2865 | ||
2866 | /* As we are eventually appending to the solution do not use | |
2867 | VEC_iterate here. */ | |
2868 | n = VEC_length (ce_s, *results); | |
2869 | for (j = 0; j < n; j++) | |
2870 | { | |
2871 | varinfo_t curr; | |
bd02b3a0 RG |
2872 | c = *VEC_index (ce_s, *results, j); |
2873 | curr = get_varinfo (c.var); | |
e5bae89b | 2874 | |
bd02b3a0 | 2875 | if (c.type == ADDRESSOF |
5006671f RG |
2876 | /* If this varinfo represents a full variable just use it. */ |
2877 | && curr->is_full_var) | |
bd02b3a0 RG |
2878 | c.offset = 0; |
2879 | else if (c.type == ADDRESSOF | |
5006671f RG |
2880 | /* If we do not know the offset add all subfields. */ |
2881 | && rhsoffset == UNKNOWN_OFFSET) | |
2882 | { | |
2883 | varinfo_t temp = lookup_vi_for_tree (curr->decl); | |
2884 | do | |
2885 | { | |
2886 | struct constraint_expr c2; | |
2887 | c2.var = temp->id; | |
2888 | c2.type = ADDRESSOF; | |
2889 | c2.offset = 0; | |
bd02b3a0 | 2890 | if (c2.var != c.var) |
779704e7 | 2891 | VEC_safe_push (ce_s, heap, *results, &c2); |
5006671f RG |
2892 | temp = temp->next; |
2893 | } | |
2894 | while (temp); | |
2895 | } | |
bd02b3a0 | 2896 | else if (c.type == ADDRESSOF) |
e5bae89b | 2897 | { |
5006671f RG |
2898 | varinfo_t temp; |
2899 | unsigned HOST_WIDE_INT offset = curr->offset + rhsoffset; | |
e5bae89b RG |
2900 | |
2901 | /* Search the sub-field which overlaps with the | |
5006671f RG |
2902 | pointed-to offset. If the result is outside of the variable |
2903 | we have to provide a conservative result, as the variable is | |
2904 | still reachable from the resulting pointer (even though it | |
2905 | technically cannot point to anything). The last and first | |
2906 | sub-fields are such conservative results. | |
e5bae89b RG |
2907 | ??? If we always had a sub-field for &object + 1 then |
2908 | we could represent this in a more precise way. */ | |
5006671f RG |
2909 | if (rhsoffset < 0 |
2910 | && curr->offset < offset) | |
2911 | offset = 0; | |
2912 | temp = first_or_preceding_vi_for_offset (curr, offset); | |
e5bae89b RG |
2913 | |
2914 | /* If the found variable is not exactly at the pointed to | |
2915 | result, we have to include the next variable in the | |
2916 | solution as well. Otherwise two increments by offset / 2 | |
2917 | do not result in the same or a conservative superset | |
2918 | solution. */ | |
5006671f | 2919 | if (temp->offset != offset |
e5bae89b RG |
2920 | && temp->next != NULL) |
2921 | { | |
2922 | struct constraint_expr c2; | |
2923 | c2.var = temp->next->id; | |
2924 | c2.type = ADDRESSOF; | |
2925 | c2.offset = 0; | |
2926 | VEC_safe_push (ce_s, heap, *results, &c2); | |
2927 | } | |
bd02b3a0 RG |
2928 | c.var = temp->id; |
2929 | c.offset = 0; | |
e5bae89b | 2930 | } |
e5bae89b | 2931 | else |
bd02b3a0 RG |
2932 | c.offset = rhsoffset; |
2933 | ||
2934 | VEC_replace (ce_s, *results, j, &c); | |
e5bae89b RG |
2935 | } |
2936 | } | |
2937 | ||
2938 | ||
c0d459f0 RG |
2939 | /* Given a COMPONENT_REF T, return the constraint_expr vector for it. |
2940 | If address_p is true the result will be taken its address of. */ | |
910fdc79 | 2941 | |
4ee00913 | 2942 | static void |
c0d459f0 RG |
2943 | get_constraint_for_component_ref (tree t, VEC(ce_s, heap) **results, |
2944 | bool address_p) | |
910fdc79 | 2945 | { |
4ee00913 | 2946 | tree orig_t = t; |
b1347638 | 2947 | HOST_WIDE_INT bitsize = -1; |
6bec9271 | 2948 | HOST_WIDE_INT bitmaxsize = -1; |
910fdc79 | 2949 | HOST_WIDE_INT bitpos; |
910fdc79 | 2950 | tree forzero; |
4ee00913 | 2951 | struct constraint_expr *result; |
910fdc79 DB |
2952 | |
2953 | /* Some people like to do cute things like take the address of | |
2954 | &0->a.b */ | |
2955 | forzero = t; | |
2956 | while (!SSA_VAR_P (forzero) && !CONSTANT_CLASS_P (forzero)) | |
4ee00913 | 2957 | forzero = TREE_OPERAND (forzero, 0); |
910fdc79 | 2958 | |
c58936b6 | 2959 | if (CONSTANT_CLASS_P (forzero) && integer_zerop (forzero)) |
910fdc79 | 2960 | { |
4ee00913 | 2961 | struct constraint_expr temp; |
c58936b6 | 2962 | |
4ee00913 DB |
2963 | temp.offset = 0; |
2964 | temp.var = integer_id; | |
2965 | temp.type = SCALAR; | |
2966 | VEC_safe_push (ce_s, heap, *results, &temp); | |
2967 | return; | |
910fdc79 | 2968 | } |
c58936b6 | 2969 | |
6bec9271 | 2970 | t = get_ref_base_and_extent (t, &bitpos, &bitsize, &bitmaxsize); |
21392f19 | 2971 | |
c0d459f0 RG |
2972 | /* Pretend to take the address of the base, we'll take care of |
2973 | adding the required subset of sub-fields below. */ | |
2974 | get_constraint_for_1 (t, results, true); | |
c0d459f0 | 2975 | gcc_assert (VEC_length (ce_s, *results) == 1); |
e5bae89b | 2976 | result = VEC_last (ce_s, *results); |
910fdc79 | 2977 | |
e5bae89b RG |
2978 | if (result->type == SCALAR |
2979 | && get_varinfo (result->var)->is_full_var) | |
2980 | /* For single-field vars do not bother about the offset. */ | |
2981 | result->offset = 0; | |
2982 | else if (result->type == SCALAR) | |
910fdc79 DB |
2983 | { |
2984 | /* In languages like C, you can access one past the end of an | |
2985 | array. You aren't allowed to dereference it, so we can | |
2986 | ignore this constraint. When we handle pointer subtraction, | |
2987 | we may have to do something cute here. */ | |
c58936b6 | 2988 | |
c0d459f0 | 2989 | if ((unsigned HOST_WIDE_INT)bitpos < get_varinfo (result->var)->fullsize |
18455d17 | 2990 | && bitmaxsize != 0) |
dd68d988 DB |
2991 | { |
2992 | /* It's also not true that the constraint will actually start at the | |
2993 | right offset, it may start in some padding. We only care about | |
2994 | setting the constraint to the first actual field it touches, so | |
c58936b6 | 2995 | walk to find it. */ |
c0d459f0 | 2996 | struct constraint_expr cexpr = *result; |
dd68d988 | 2997 | varinfo_t curr; |
c0d459f0 RG |
2998 | VEC_pop (ce_s, *results); |
2999 | cexpr.offset = 0; | |
3000 | for (curr = get_varinfo (cexpr.var); curr; curr = curr->next) | |
dd68d988 | 3001 | { |
63d195d5 | 3002 | if (ranges_overlap_p (curr->offset, curr->size, |
c0d459f0 | 3003 | bitpos, bitmaxsize)) |
dd68d988 | 3004 | { |
c0d459f0 RG |
3005 | cexpr.var = curr->id; |
3006 | VEC_safe_push (ce_s, heap, *results, &cexpr); | |
3007 | if (address_p) | |
3008 | break; | |
dd68d988 DB |
3009 | } |
3010 | } | |
e5bae89b RG |
3011 | /* If we are going to take the address of this field then |
3012 | to be able to compute reachability correctly add at least | |
3013 | the last field of the variable. */ | |
3014 | if (address_p | |
3015 | && VEC_length (ce_s, *results) == 0) | |
3016 | { | |
3017 | curr = get_varinfo (cexpr.var); | |
3018 | while (curr->next != NULL) | |
3019 | curr = curr->next; | |
3020 | cexpr.var = curr->id; | |
3021 | VEC_safe_push (ce_s, heap, *results, &cexpr); | |
3022 | } | |
3023 | else | |
3024 | /* Assert that we found *some* field there. The user couldn't be | |
3025 | accessing *only* padding. */ | |
3026 | /* Still the user could access one past the end of an array | |
3027 | embedded in a struct resulting in accessing *only* padding. */ | |
3028 | gcc_assert (VEC_length (ce_s, *results) >= 1 | |
3029 | || ref_contains_array_ref (orig_t)); | |
dd68d988 | 3030 | } |
18455d17 RG |
3031 | else if (bitmaxsize == 0) |
3032 | { | |
3033 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3034 | fprintf (dump_file, "Access to zero-sized part of variable," | |
3035 | "ignoring\n"); | |
3036 | } | |
910fdc79 DB |
3037 | else |
3038 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3039 | fprintf (dump_file, "Access to past the end of variable, ignoring\n"); | |
910fdc79 | 3040 | } |
5006671f | 3041 | else if (result->type == DEREF) |
7b765bed | 3042 | { |
5006671f RG |
3043 | /* If we do not know exactly where the access goes say so. Note |
3044 | that only for non-structure accesses we know that we access | |
3045 | at most one subfiled of any variable. */ | |
3046 | if (bitpos == -1 | |
3047 | || bitsize != bitmaxsize | |
3048 | || AGGREGATE_TYPE_P (TREE_TYPE (orig_t))) | |
3049 | result->offset = UNKNOWN_OFFSET; | |
3050 | else | |
3051 | result->offset = bitpos; | |
7b765bed | 3052 | } |
b51605c4 RG |
3053 | else if (result->type == ADDRESSOF) |
3054 | { | |
3055 | /* We can end up here for component references on a | |
3056 | VIEW_CONVERT_EXPR <>(&foobar). */ | |
3057 | result->type = SCALAR; | |
3058 | result->var = anything_id; | |
3059 | result->offset = 0; | |
3060 | } | |
c0d459f0 | 3061 | else |
5006671f | 3062 | gcc_unreachable (); |
910fdc79 DB |
3063 | } |
3064 | ||
3065 | ||
3066 | /* Dereference the constraint expression CONS, and return the result. | |
3067 | DEREF (ADDRESSOF) = SCALAR | |
3068 | DEREF (SCALAR) = DEREF | |
3069 | DEREF (DEREF) = (temp = DEREF1; result = DEREF(temp)) | |
3070 | This is needed so that we can handle dereferencing DEREF constraints. */ | |
3071 | ||
4ee00913 DB |
3072 | static void |
3073 | do_deref (VEC (ce_s, heap) **constraints) | |
910fdc79 | 3074 | { |
4ee00913 DB |
3075 | struct constraint_expr *c; |
3076 | unsigned int i = 0; | |
c58936b6 | 3077 | |
4ee00913 | 3078 | for (i = 0; VEC_iterate (ce_s, *constraints, i, c); i++) |
910fdc79 | 3079 | { |
4ee00913 DB |
3080 | if (c->type == SCALAR) |
3081 | c->type = DEREF; | |
3082 | else if (c->type == ADDRESSOF) | |
3083 | c->type = SCALAR; | |
3084 | else if (c->type == DEREF) | |
3085 | { | |
b14e9388 RG |
3086 | struct constraint_expr tmplhs; |
3087 | tmplhs = new_scalar_tmp_constraint_exp ("dereftmp"); | |
4ee00913 DB |
3088 | process_constraint (new_constraint (tmplhs, *c)); |
3089 | c->var = tmplhs.var; | |
3090 | } | |
3091 | else | |
3092 | gcc_unreachable (); | |
910fdc79 | 3093 | } |
910fdc79 DB |
3094 | } |
3095 | ||
1d24fdd9 RG |
3096 | static void get_constraint_for_1 (tree, VEC (ce_s, heap) **, bool); |
3097 | ||
3098 | /* Given a tree T, return the constraint expression for taking the | |
3099 | address of it. */ | |
3100 | ||
3101 | static void | |
3102 | get_constraint_for_address_of (tree t, VEC (ce_s, heap) **results) | |
3103 | { | |
3104 | struct constraint_expr *c; | |
3105 | unsigned int i; | |
3106 | ||
3107 | get_constraint_for_1 (t, results, true); | |
3108 | ||
3109 | for (i = 0; VEC_iterate (ce_s, *results, i, c); i++) | |
3110 | { | |
3111 | if (c->type == DEREF) | |
3112 | c->type = SCALAR; | |
3113 | else | |
3114 | c->type = ADDRESSOF; | |
3115 | } | |
3116 | } | |
3117 | ||
910fdc79 DB |
3118 | /* Given a tree T, return the constraint expression for it. */ |
3119 | ||
4ee00913 | 3120 | static void |
c0d459f0 | 3121 | get_constraint_for_1 (tree t, VEC (ce_s, heap) **results, bool address_p) |
910fdc79 DB |
3122 | { |
3123 | struct constraint_expr temp; | |
3124 | ||
3125 | /* x = integer is all glommed to a single variable, which doesn't | |
3126 | point to anything by itself. That is, of course, unless it is an | |
3127 | integer constant being treated as a pointer, in which case, we | |
3128 | will return that this is really the addressof anything. This | |
3129 | happens below, since it will fall into the default case. The only | |
3130 | case we know something about an integer treated like a pointer is | |
3131 | when it is the NULL pointer, and then we just say it points to | |
89ebafc6 PB |
3132 | NULL. |
3133 | ||
3134 | Do not do that if -fno-delete-null-pointer-checks though, because | |
3135 | in that case *NULL does not fail, so it _should_ alias *anything. | |
3136 | It is not worth adding a new option or renaming the existing one, | |
3137 | since this case is relatively obscure. */ | |
3138 | if (flag_delete_null_pointer_checks | |
5006671f RG |
3139 | && ((TREE_CODE (t) == INTEGER_CST |
3140 | && integer_zerop (t)) | |
3141 | /* The only valid CONSTRUCTORs in gimple with pointer typed | |
3142 | elements are zero-initializer. */ | |
3143 | || TREE_CODE (t) == CONSTRUCTOR)) | |
910fdc79 DB |
3144 | { |
3145 | temp.var = nothing_id; | |
3146 | temp.type = ADDRESSOF; | |
3147 | temp.offset = 0; | |
4ee00913 DB |
3148 | VEC_safe_push (ce_s, heap, *results, &temp); |
3149 | return; | |
910fdc79 DB |
3150 | } |
3151 | ||
bd1f29d9 EB |
3152 | /* String constants are read-only. */ |
3153 | if (TREE_CODE (t) == STRING_CST) | |
3154 | { | |
3155 | temp.var = readonly_id; | |
3156 | temp.type = SCALAR; | |
3157 | temp.offset = 0; | |
3158 | VEC_safe_push (ce_s, heap, *results, &temp); | |
3159 | return; | |
3160 | } | |
3161 | ||
910fdc79 DB |
3162 | switch (TREE_CODE_CLASS (TREE_CODE (t))) |
3163 | { | |
3164 | case tcc_expression: | |
3165 | { | |
3166 | switch (TREE_CODE (t)) | |
3167 | { | |
3168 | case ADDR_EXPR: | |
1d24fdd9 RG |
3169 | get_constraint_for_address_of (TREE_OPERAND (t, 0), results); |
3170 | return; | |
e5bae89b | 3171 | default:; |
910fdc79 | 3172 | } |
e5bae89b | 3173 | break; |
910fdc79 DB |
3174 | } |
3175 | case tcc_reference: | |
3176 | { | |
3177 | switch (TREE_CODE (t)) | |
3178 | { | |
3179 | case INDIRECT_REF: | |
3180 | { | |
c0d459f0 | 3181 | get_constraint_for_1 (TREE_OPERAND (t, 0), results, address_p); |
4ee00913 DB |
3182 | do_deref (results); |
3183 | return; | |
910fdc79 DB |
3184 | } |
3185 | case ARRAY_REF: | |
32961db5 | 3186 | case ARRAY_RANGE_REF: |
910fdc79 | 3187 | case COMPONENT_REF: |
c0d459f0 | 3188 | get_constraint_for_component_ref (t, results, address_p); |
4ee00913 | 3189 | return; |
5006671f RG |
3190 | case VIEW_CONVERT_EXPR: |
3191 | get_constraint_for_1 (TREE_OPERAND (t, 0), results, address_p); | |
3192 | return; | |
3193 | /* We are missing handling for TARGET_MEM_REF here. */ | |
e5bae89b | 3194 | default:; |
910fdc79 | 3195 | } |
e5bae89b | 3196 | break; |
910fdc79 | 3197 | } |
910fdc79 DB |
3198 | case tcc_exceptional: |
3199 | { | |
3200 | switch (TREE_CODE (t)) | |
3201 | { | |
910fdc79 | 3202 | case SSA_NAME: |
4ee00913 | 3203 | { |
c0d459f0 | 3204 | get_constraint_for_ssa_var (t, results, address_p); |
4ee00913 DB |
3205 | return; |
3206 | } | |
e5bae89b | 3207 | default:; |
910fdc79 | 3208 | } |
e5bae89b | 3209 | break; |
910fdc79 DB |
3210 | } |
3211 | case tcc_declaration: | |
4ee00913 | 3212 | { |
c0d459f0 | 3213 | get_constraint_for_ssa_var (t, results, address_p); |
4ee00913 DB |
3214 | return; |
3215 | } | |
e5bae89b | 3216 | default:; |
910fdc79 | 3217 | } |
e5bae89b RG |
3218 | |
3219 | /* The default fallback is a constraint from anything. */ | |
3220 | temp.type = ADDRESSOF; | |
3221 | temp.var = anything_id; | |
3222 | temp.offset = 0; | |
3223 | VEC_safe_push (ce_s, heap, *results, &temp); | |
910fdc79 DB |
3224 | } |
3225 | ||
c0d459f0 RG |
3226 | /* Given a gimple tree T, return the constraint expression vector for it. */ |
3227 | ||
3228 | static void | |
3229 | get_constraint_for (tree t, VEC (ce_s, heap) **results) | |
3230 | { | |
3231 | gcc_assert (VEC_length (ce_s, *results) == 0); | |
3232 | ||
3233 | get_constraint_for_1 (t, results, false); | |
3234 | } | |
910fdc79 | 3235 | |
779704e7 RG |
3236 | |
3237 | /* Efficiently generates constraints from all entries in *RHSC to all | |
3238 | entries in *LHSC. */ | |
3239 | ||
3240 | static void | |
3241 | process_all_all_constraints (VEC (ce_s, heap) *lhsc, VEC (ce_s, heap) *rhsc) | |
3242 | { | |
3243 | struct constraint_expr *lhsp, *rhsp; | |
3244 | unsigned i, j; | |
3245 | ||
3246 | if (VEC_length (ce_s, lhsc) <= 1 | |
3247 | || VEC_length (ce_s, rhsc) <= 1) | |
3248 | { | |
3249 | for (i = 0; VEC_iterate (ce_s, lhsc, i, lhsp); ++i) | |
3250 | for (j = 0; VEC_iterate (ce_s, rhsc, j, rhsp); ++j) | |
3251 | process_constraint (new_constraint (*lhsp, *rhsp)); | |
3252 | } | |
3253 | else | |
3254 | { | |
3255 | struct constraint_expr tmp; | |
b14e9388 | 3256 | tmp = new_scalar_tmp_constraint_exp ("allalltmp"); |
779704e7 RG |
3257 | for (i = 0; VEC_iterate (ce_s, rhsc, i, rhsp); ++i) |
3258 | process_constraint (new_constraint (tmp, *rhsp)); | |
3259 | for (i = 0; VEC_iterate (ce_s, lhsc, i, lhsp); ++i) | |
3260 | process_constraint (new_constraint (*lhsp, tmp)); | |
3261 | } | |
3262 | } | |
3263 | ||
910fdc79 DB |
3264 | /* Handle aggregate copies by expanding into copies of the respective |
3265 | fields of the structures. */ | |
3266 | ||
3267 | static void | |
3268 | do_structure_copy (tree lhsop, tree rhsop) | |
3269 | { | |
5006671f | 3270 | struct constraint_expr *lhsp, *rhsp; |
4ee00913 | 3271 | VEC (ce_s, heap) *lhsc = NULL, *rhsc = NULL; |
5006671f RG |
3272 | unsigned j; |
3273 | ||
3274 | get_constraint_for (lhsop, &lhsc); | |
3275 | get_constraint_for (rhsop, &rhsc); | |
3276 | lhsp = VEC_index (ce_s, lhsc, 0); | |
3277 | rhsp = VEC_index (ce_s, rhsc, 0); | |
3278 | if (lhsp->type == DEREF | |
3279 | || (lhsp->type == ADDRESSOF && lhsp->var == anything_id) | |
3280 | || rhsp->type == DEREF) | |
779704e7 | 3281 | process_all_all_constraints (lhsc, rhsc); |
5006671f RG |
3282 | else if (lhsp->type == SCALAR |
3283 | && (rhsp->type == SCALAR | |
3284 | || rhsp->type == ADDRESSOF)) | |
910fdc79 | 3285 | { |
5006671f RG |
3286 | tree lhsbase, rhsbase; |
3287 | HOST_WIDE_INT lhssize, lhsmaxsize, lhsoffset; | |
3288 | HOST_WIDE_INT rhssize, rhsmaxsize, rhsoffset; | |
3289 | unsigned k = 0; | |
3290 | lhsbase = get_ref_base_and_extent (lhsop, &lhsoffset, | |
3291 | &lhssize, &lhsmaxsize); | |
3292 | rhsbase = get_ref_base_and_extent (rhsop, &rhsoffset, | |
3293 | &rhssize, &rhsmaxsize); | |
3294 | for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp);) | |
910fdc79 | 3295 | { |
5006671f RG |
3296 | varinfo_t lhsv, rhsv; |
3297 | rhsp = VEC_index (ce_s, rhsc, k); | |
3298 | lhsv = get_varinfo (lhsp->var); | |
3299 | rhsv = get_varinfo (rhsp->var); | |
3300 | if (lhsv->may_have_pointers | |
3301 | && ranges_overlap_p (lhsv->offset + rhsoffset, lhsv->size, | |
3302 | rhsv->offset + lhsoffset, rhsv->size)) | |
3303 | process_constraint (new_constraint (*lhsp, *rhsp)); | |
3304 | if (lhsv->offset + rhsoffset + lhsv->size | |
3305 | > rhsv->offset + lhsoffset + rhsv->size) | |
3306 | { | |
3307 | ++k; | |
3308 | if (k >= VEC_length (ce_s, rhsc)) | |
3309 | break; | |
3310 | } | |
910fdc79 | 3311 | else |
5006671f | 3312 | ++j; |
910fdc79 DB |
3313 | } |
3314 | } | |
3315 | else | |
5006671f | 3316 | gcc_unreachable (); |
a5eadacc | 3317 | |
5006671f RG |
3318 | VEC_free (ce_s, heap, lhsc); |
3319 | VEC_free (ce_s, heap, rhsc); | |
910fdc79 DB |
3320 | } |
3321 | ||
b7091901 RG |
3322 | /* Create a constraint ID = OP. */ |
3323 | ||
3324 | static void | |
3325 | make_constraint_to (unsigned id, tree op) | |
3326 | { | |
3327 | VEC(ce_s, heap) *rhsc = NULL; | |
3328 | struct constraint_expr *c; | |
3329 | struct constraint_expr includes; | |
3330 | unsigned int j; | |
3331 | ||
3332 | includes.var = id; | |
3333 | includes.offset = 0; | |
3334 | includes.type = SCALAR; | |
3335 | ||
3336 | get_constraint_for (op, &rhsc); | |
3337 | for (j = 0; VEC_iterate (ce_s, rhsc, j, c); j++) | |
faf2ecc5 | 3338 | process_constraint (new_constraint (includes, *c)); |
b7091901 RG |
3339 | VEC_free (ce_s, heap, rhsc); |
3340 | } | |
3341 | ||
74d27244 RG |
3342 | /* Create a constraint ID = &FROM. */ |
3343 | ||
3344 | static void | |
3345 | make_constraint_from (varinfo_t vi, int from) | |
3346 | { | |
3347 | struct constraint_expr lhs, rhs; | |
3348 | ||
3349 | lhs.var = vi->id; | |
3350 | lhs.offset = 0; | |
3351 | lhs.type = SCALAR; | |
3352 | ||
3353 | rhs.var = from; | |
3354 | rhs.offset = 0; | |
3355 | rhs.type = ADDRESSOF; | |
3356 | process_constraint (new_constraint (lhs, rhs)); | |
3357 | } | |
3358 | ||
3359 | /* Create a constraint ID = FROM. */ | |
3360 | ||
3361 | static void | |
3362 | make_copy_constraint (varinfo_t vi, int from) | |
3363 | { | |
3364 | struct constraint_expr lhs, rhs; | |
3365 | ||
3366 | lhs.var = vi->id; | |
3367 | lhs.offset = 0; | |
3368 | lhs.type = SCALAR; | |
3369 | ||
3370 | rhs.var = from; | |
3371 | rhs.offset = 0; | |
3372 | rhs.type = SCALAR; | |
3373 | process_constraint (new_constraint (lhs, rhs)); | |
3374 | } | |
3375 | ||
b7091901 RG |
3376 | /* Make constraints necessary to make OP escape. */ |
3377 | ||
3378 | static void | |
3379 | make_escape_constraint (tree op) | |
3380 | { | |
3381 | make_constraint_to (escaped_id, op); | |
3382 | } | |
3383 | ||
74d27244 RG |
3384 | /* Create a new artificial heap variable with NAME and make a |
3385 | constraint from it to LHS. Return the created variable. */ | |
3386 | ||
3387 | static varinfo_t | |
3388 | make_constraint_from_heapvar (varinfo_t lhs, const char *name) | |
3389 | { | |
3390 | varinfo_t vi; | |
8bc88f25 | 3391 | tree heapvar = heapvar_lookup (lhs->decl, lhs->offset); |
74d27244 RG |
3392 | |
3393 | if (heapvar == NULL_TREE) | |
3394 | { | |
3395 | var_ann_t ann; | |
3396 | heapvar = create_tmp_var_raw (ptr_type_node, name); | |
3397 | DECL_EXTERNAL (heapvar) = 1; | |
3398 | ||
8bc88f25 | 3399 | heapvar_insert (lhs->decl, lhs->offset, heapvar); |
74d27244 RG |
3400 | |
3401 | ann = get_var_ann (heapvar); | |
3402 | ann->is_heapvar = 1; | |
3403 | } | |
3404 | ||
3405 | /* For global vars we need to add a heapvar to the list of referenced | |
3406 | vars of a different function than it was created for originally. */ | |
3407 | if (gimple_referenced_vars (cfun)) | |
3408 | add_referenced_var (heapvar); | |
3409 | ||
3410 | vi = new_var_info (heapvar, name); | |
3411 | vi->is_artificial_var = true; | |
3412 | vi->is_heap_var = true; | |
3413 | vi->is_unknown_size_var = true; | |
b41e33fe | 3414 | vi->offset = 0; |
74d27244 RG |
3415 | vi->fullsize = ~0; |
3416 | vi->size = ~0; | |
3417 | vi->is_full_var = true; | |
3418 | insert_vi_for_tree (heapvar, vi); | |
3419 | ||
3420 | make_constraint_from (lhs, vi->id); | |
3421 | ||
3422 | return vi; | |
3423 | } | |
3424 | ||
3425 | /* Create a new artificial heap variable with NAME and make a | |
3426 | constraint from it to LHS. Set flags according to a tag used | |
3427 | for tracking restrict pointers. */ | |
3428 | ||
3429 | static void | |
3430 | make_constraint_from_restrict (varinfo_t lhs, const char *name) | |
3431 | { | |
3432 | varinfo_t vi; | |
3433 | vi = make_constraint_from_heapvar (lhs, name); | |
3434 | vi->is_restrict_var = 1; | |
3435 | vi->is_global_var = 0; | |
3436 | vi->is_special_var = 1; | |
3437 | vi->may_have_pointers = 0; | |
3438 | } | |
3439 | ||
7b765bed DB |
3440 | /* For non-IPA mode, generate constraints necessary for a call on the |
3441 | RHS. */ | |
3442 | ||
3443 | static void | |
472c7fbd | 3444 | handle_rhs_call (gimple stmt, VEC(ce_s, heap) **results) |
7b765bed | 3445 | { |
472c7fbd | 3446 | struct constraint_expr rhsc; |
726a989a | 3447 | unsigned i; |
7b765bed | 3448 | |
726a989a RB |
3449 | for (i = 0; i < gimple_call_num_args (stmt); ++i) |
3450 | { | |
3451 | tree arg = gimple_call_arg (stmt, i); | |
3452 | ||
3453 | /* Find those pointers being passed, and make sure they end up | |
3454 | pointing to anything. */ | |
3455 | if (could_have_pointers (arg)) | |
3456 | make_escape_constraint (arg); | |
3457 | } | |
b7091901 RG |
3458 | |
3459 | /* The static chain escapes as well. */ | |
726a989a RB |
3460 | if (gimple_call_chain (stmt)) |
3461 | make_escape_constraint (gimple_call_chain (stmt)); | |
472c7fbd | 3462 | |
1d24fdd9 RG |
3463 | /* And if we applied NRV the address of the return slot escapes as well. */ |
3464 | if (gimple_call_return_slot_opt_p (stmt) | |
3465 | && gimple_call_lhs (stmt) != NULL_TREE | |
4d61856d | 3466 | && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt)))) |
1d24fdd9 RG |
3467 | { |
3468 | VEC(ce_s, heap) *tmpc = NULL; | |
3469 | struct constraint_expr lhsc, *c; | |
3470 | get_constraint_for_address_of (gimple_call_lhs (stmt), &tmpc); | |
3471 | lhsc.var = escaped_id; | |
3472 | lhsc.offset = 0; | |
3473 | lhsc.type = SCALAR; | |
3474 | for (i = 0; VEC_iterate (ce_s, tmpc, i, c); ++i) | |
3475 | process_constraint (new_constraint (lhsc, *c)); | |
3476 | VEC_free(ce_s, heap, tmpc); | |
3477 | } | |
3478 | ||
5006671f RG |
3479 | /* Regular functions return nonlocal memory. */ |
3480 | rhsc.var = nonlocal_id; | |
472c7fbd | 3481 | rhsc.offset = 0; |
5006671f | 3482 | rhsc.type = SCALAR; |
472c7fbd | 3483 | VEC_safe_push (ce_s, heap, *results, &rhsc); |
7b765bed | 3484 | } |
e8ca4159 | 3485 | |
af947da7 RG |
3486 | /* For non-IPA mode, generate constraints necessary for a call |
3487 | that returns a pointer and assigns it to LHS. This simply makes | |
b7091901 | 3488 | the LHS point to global and escaped variables. */ |
af947da7 RG |
3489 | |
3490 | static void | |
472c7fbd | 3491 | handle_lhs_call (tree lhs, int flags, VEC(ce_s, heap) *rhsc) |
af947da7 RG |
3492 | { |
3493 | VEC(ce_s, heap) *lhsc = NULL; | |
af947da7 | 3494 | |
b7091901 | 3495 | get_constraint_for (lhs, &lhsc); |
183ae595 RG |
3496 | |
3497 | if (flags & ECF_MALLOC) | |
3498 | { | |
183ae595 | 3499 | varinfo_t vi; |
74d27244 | 3500 | vi = make_constraint_from_heapvar (get_vi_for_tree (lhs), "HEAP"); |
14c41b9b RG |
3501 | /* We delay marking allocated storage global until we know if |
3502 | it escapes. */ | |
91deb937 | 3503 | DECL_EXTERNAL (vi->decl) = 0; |
14c41b9b | 3504 | vi->is_global_var = 0; |
183ae595 | 3505 | } |
472c7fbd | 3506 | else if (VEC_length (ce_s, rhsc) > 0) |
183ae595 | 3507 | { |
472c7fbd RG |
3508 | /* If the store is to a global decl make sure to |
3509 | add proper escape constraints. */ | |
3510 | lhs = get_base_address (lhs); | |
3511 | if (lhs | |
3512 | && DECL_P (lhs) | |
3513 | && is_global_var (lhs)) | |
3514 | { | |
3515 | struct constraint_expr tmpc; | |
3516 | tmpc.var = escaped_id; | |
3517 | tmpc.offset = 0; | |
3518 | tmpc.type = SCALAR; | |
3519 | VEC_safe_push (ce_s, heap, lhsc, &tmpc); | |
3520 | } | |
779704e7 | 3521 | process_all_all_constraints (lhsc, rhsc); |
183ae595 | 3522 | } |
b7091901 RG |
3523 | VEC_free (ce_s, heap, lhsc); |
3524 | } | |
3525 | ||
3526 | /* For non-IPA mode, generate constraints necessary for a call of a | |
3527 | const function that returns a pointer in the statement STMT. */ | |
3528 | ||
3529 | static void | |
472c7fbd | 3530 | handle_const_call (gimple stmt, VEC(ce_s, heap) **results) |
b7091901 | 3531 | { |
b14e9388 | 3532 | struct constraint_expr rhsc; |
472c7fbd | 3533 | unsigned int k; |
b7091901 | 3534 | |
472c7fbd RG |
3535 | /* Treat nested const functions the same as pure functions as far |
3536 | as the static chain is concerned. */ | |
726a989a | 3537 | if (gimple_call_chain (stmt)) |
b7091901 | 3538 | { |
472c7fbd RG |
3539 | make_constraint_to (callused_id, gimple_call_chain (stmt)); |
3540 | rhsc.var = callused_id; | |
b7091901 | 3541 | rhsc.offset = 0; |
472c7fbd RG |
3542 | rhsc.type = SCALAR; |
3543 | VEC_safe_push (ce_s, heap, *results, &rhsc); | |
b7091901 RG |
3544 | } |
3545 | ||
b7091901 | 3546 | /* May return arguments. */ |
726a989a RB |
3547 | for (k = 0; k < gimple_call_num_args (stmt); ++k) |
3548 | { | |
3549 | tree arg = gimple_call_arg (stmt, k); | |
3550 | ||
3551 | if (could_have_pointers (arg)) | |
3552 | { | |
3553 | VEC(ce_s, heap) *argc = NULL; | |
b14e9388 | 3554 | unsigned i; |
726a989a | 3555 | struct constraint_expr *argp; |
726a989a | 3556 | get_constraint_for (arg, &argc); |
b14e9388 RG |
3557 | for (i = 0; VEC_iterate (ce_s, argc, i, argp); ++i) |
3558 | VEC_safe_push (ce_s, heap, *results, argp); | |
3559 | VEC_free(ce_s, heap, argc); | |
726a989a RB |
3560 | } |
3561 | } | |
b7091901 | 3562 | |
472c7fbd RG |
3563 | /* May return addresses of globals. */ |
3564 | rhsc.var = nonlocal_id; | |
3565 | rhsc.offset = 0; | |
3566 | rhsc.type = ADDRESSOF; | |
3567 | VEC_safe_push (ce_s, heap, *results, &rhsc); | |
af947da7 RG |
3568 | } |
3569 | ||
15c15196 RG |
3570 | /* For non-IPA mode, generate constraints necessary for a call to a |
3571 | pure function in statement STMT. */ | |
3572 | ||
3573 | static void | |
472c7fbd | 3574 | handle_pure_call (gimple stmt, VEC(ce_s, heap) **results) |
15c15196 | 3575 | { |
472c7fbd | 3576 | struct constraint_expr rhsc; |
726a989a | 3577 | unsigned i; |
472c7fbd | 3578 | bool need_callused = false; |
15c15196 RG |
3579 | |
3580 | /* Memory reached from pointer arguments is call-used. */ | |
726a989a RB |
3581 | for (i = 0; i < gimple_call_num_args (stmt); ++i) |
3582 | { | |
3583 | tree arg = gimple_call_arg (stmt, i); | |
3584 | ||
3585 | if (could_have_pointers (arg)) | |
472c7fbd RG |
3586 | { |
3587 | make_constraint_to (callused_id, arg); | |
3588 | need_callused = true; | |
3589 | } | |
726a989a | 3590 | } |
15c15196 RG |
3591 | |
3592 | /* The static chain is used as well. */ | |
726a989a | 3593 | if (gimple_call_chain (stmt)) |
15c15196 | 3594 | { |
472c7fbd RG |
3595 | make_constraint_to (callused_id, gimple_call_chain (stmt)); |
3596 | need_callused = true; | |
3597 | } | |
15c15196 | 3598 | |
5006671f | 3599 | /* Pure functions may return callused and nonlocal memory. */ |
472c7fbd RG |
3600 | if (need_callused) |
3601 | { | |
15c15196 RG |
3602 | rhsc.var = callused_id; |
3603 | rhsc.offset = 0; | |
472c7fbd RG |
3604 | rhsc.type = SCALAR; |
3605 | VEC_safe_push (ce_s, heap, *results, &rhsc); | |
15c15196 | 3606 | } |
5006671f | 3607 | rhsc.var = nonlocal_id; |
472c7fbd | 3608 | rhsc.offset = 0; |
5006671f | 3609 | rhsc.type = SCALAR; |
472c7fbd | 3610 | VEC_safe_push (ce_s, heap, *results, &rhsc); |
15c15196 RG |
3611 | } |
3612 | ||
e8ca4159 DN |
3613 | /* Walk statement T setting up aliasing constraints according to the |
3614 | references found in T. This function is the main part of the | |
3615 | constraint builder. AI points to auxiliary alias information used | |
3616 | when building alias sets and computing alias grouping heuristics. */ | |
910fdc79 DB |
3617 | |
3618 | static void | |
726a989a | 3619 | find_func_aliases (gimple origt) |
910fdc79 | 3620 | { |
726a989a | 3621 | gimple t = origt; |
4ee00913 DB |
3622 | VEC(ce_s, heap) *lhsc = NULL; |
3623 | VEC(ce_s, heap) *rhsc = NULL; | |
3624 | struct constraint_expr *c; | |
910fdc79 | 3625 | |
e8ca4159 | 3626 | /* Now build constraints expressions. */ |
726a989a | 3627 | if (gimple_code (t) == GIMPLE_PHI) |
e8ca4159 | 3628 | { |
726a989a | 3629 | gcc_assert (!AGGREGATE_TYPE_P (TREE_TYPE (gimple_phi_result (t)))); |
6df11ca1 | 3630 | |
e8ca4159 DN |
3631 | /* Only care about pointers and structures containing |
3632 | pointers. */ | |
726a989a | 3633 | if (could_have_pointers (gimple_phi_result (t))) |
e8ca4159 | 3634 | { |
726a989a | 3635 | size_t i; |
4ee00913 | 3636 | unsigned int j; |
c58936b6 | 3637 | |
4ee00913 DB |
3638 | /* For a phi node, assign all the arguments to |
3639 | the result. */ | |
726a989a RB |
3640 | get_constraint_for (gimple_phi_result (t), &lhsc); |
3641 | for (i = 0; i < gimple_phi_num_args (t); i++) | |
c58936b6 | 3642 | { |
0a4288d9 RG |
3643 | tree rhstype; |
3644 | tree strippedrhs = PHI_ARG_DEF (t, i); | |
3645 | ||
3646 | STRIP_NOPS (strippedrhs); | |
3647 | rhstype = TREE_TYPE (strippedrhs); | |
726a989a | 3648 | get_constraint_for (gimple_phi_arg_def (t, i), &rhsc); |
0a4288d9 | 3649 | |
4ee00913 DB |
3650 | for (j = 0; VEC_iterate (ce_s, lhsc, j, c); j++) |
3651 | { | |
3652 | struct constraint_expr *c2; | |
3653 | while (VEC_length (ce_s, rhsc) > 0) | |
3654 | { | |
3655 | c2 = VEC_last (ce_s, rhsc); | |
3656 | process_constraint (new_constraint (*c, *c2)); | |
3657 | VEC_pop (ce_s, rhsc); | |
3658 | } | |
3659 | } | |
c58936b6 | 3660 | } |
4ee00913 DB |
3661 | } |
3662 | } | |
3663 | /* In IPA mode, we need to generate constraints to pass call | |
726a989a RB |
3664 | arguments through their calls. There are two cases, |
3665 | either a GIMPLE_CALL returning a value, or just a plain | |
3666 | GIMPLE_CALL when we are not. | |
7b765bed DB |
3667 | |
3668 | In non-ipa mode, we need to generate constraints for each | |
3669 | pointer passed by address. */ | |
726a989a | 3670 | else if (is_gimple_call (t)) |
4ee00913 | 3671 | { |
5c245b95 RG |
3672 | tree fndecl = gimple_call_fndecl (t); |
3673 | if (fndecl != NULL_TREE | |
779704e7 RG |
3674 | && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL) |
3675 | /* ??? All builtins that are handled here need to be handled | |
3676 | in the alias-oracle query functions explicitly! */ | |
3677 | switch (DECL_FUNCTION_CODE (fndecl)) | |
3678 | { | |
3679 | /* All the following functions return a pointer to the same object | |
3680 | as their first argument points to. The functions do not add | |
3681 | to the ESCAPED solution. The functions make the first argument | |
3682 | pointed to memory point to what the second argument pointed to | |
3683 | memory points to. */ | |
3684 | case BUILT_IN_STRCPY: | |
3685 | case BUILT_IN_STRNCPY: | |
3686 | case BUILT_IN_BCOPY: | |
3687 | case BUILT_IN_MEMCPY: | |
3688 | case BUILT_IN_MEMMOVE: | |
3689 | case BUILT_IN_MEMPCPY: | |
3690 | case BUILT_IN_STPCPY: | |
3691 | case BUILT_IN_STPNCPY: | |
3692 | case BUILT_IN_STRCAT: | |
3693 | case BUILT_IN_STRNCAT: | |
3694 | { | |
3695 | tree res = gimple_call_lhs (t); | |
1307c758 RG |
3696 | tree dest = gimple_call_arg (t, (DECL_FUNCTION_CODE (fndecl) |
3697 | == BUILT_IN_BCOPY ? 1 : 0)); | |
3698 | tree src = gimple_call_arg (t, (DECL_FUNCTION_CODE (fndecl) | |
3699 | == BUILT_IN_BCOPY ? 0 : 1)); | |
779704e7 RG |
3700 | if (res != NULL_TREE) |
3701 | { | |
3702 | get_constraint_for (res, &lhsc); | |
3703 | if (DECL_FUNCTION_CODE (fndecl) == BUILT_IN_MEMPCPY | |
3704 | || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STPCPY | |
3705 | || DECL_FUNCTION_CODE (fndecl) == BUILT_IN_STPNCPY) | |
3706 | get_constraint_for_ptr_offset (dest, NULL_TREE, &rhsc); | |
3707 | else | |
3708 | get_constraint_for (dest, &rhsc); | |
3709 | process_all_all_constraints (lhsc, rhsc); | |
3710 | VEC_free (ce_s, heap, lhsc); | |
3711 | VEC_free (ce_s, heap, rhsc); | |
3712 | } | |
3713 | get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc); | |
3714 | get_constraint_for_ptr_offset (src, NULL_TREE, &rhsc); | |
3715 | do_deref (&lhsc); | |
3716 | do_deref (&rhsc); | |
3717 | process_all_all_constraints (lhsc, rhsc); | |
3718 | VEC_free (ce_s, heap, lhsc); | |
3719 | VEC_free (ce_s, heap, rhsc); | |
3720 | return; | |
3721 | } | |
3722 | case BUILT_IN_MEMSET: | |
3723 | { | |
3724 | tree res = gimple_call_lhs (t); | |
3725 | tree dest = gimple_call_arg (t, 0); | |
3726 | unsigned i; | |
3727 | ce_s *lhsp; | |
3728 | struct constraint_expr ac; | |
3729 | if (res != NULL_TREE) | |
3730 | { | |
3731 | get_constraint_for (res, &lhsc); | |
3732 | get_constraint_for (dest, &rhsc); | |
3733 | process_all_all_constraints (lhsc, rhsc); | |
3734 | VEC_free (ce_s, heap, lhsc); | |
3735 | VEC_free (ce_s, heap, rhsc); | |
3736 | } | |
3737 | get_constraint_for_ptr_offset (dest, NULL_TREE, &lhsc); | |
3738 | do_deref (&lhsc); | |
825be69e RG |
3739 | if (flag_delete_null_pointer_checks |
3740 | && integer_zerop (gimple_call_arg (t, 1))) | |
3741 | { | |
3742 | ac.type = ADDRESSOF; | |
3743 | ac.var = nothing_id; | |
3744 | } | |
3745 | else | |
3746 | { | |
3747 | ac.type = SCALAR; | |
3748 | ac.var = integer_id; | |
3749 | } | |
779704e7 RG |
3750 | ac.offset = 0; |
3751 | for (i = 0; VEC_iterate (ce_s, lhsc, i, lhsp); ++i) | |
3752 | process_constraint (new_constraint (*lhsp, ac)); | |
3753 | VEC_free (ce_s, heap, lhsc); | |
3754 | return; | |
3755 | } | |
3756 | /* All the following functions do not return pointers, do not | |
3757 | modify the points-to sets of memory reachable from their | |
3758 | arguments and do not add to the ESCAPED solution. */ | |
3759 | case BUILT_IN_SINCOS: | |
3760 | case BUILT_IN_SINCOSF: | |
3761 | case BUILT_IN_SINCOSL: | |
3762 | case BUILT_IN_FREXP: | |
3763 | case BUILT_IN_FREXPF: | |
3764 | case BUILT_IN_FREXPL: | |
3765 | case BUILT_IN_GAMMA_R: | |
3766 | case BUILT_IN_GAMMAF_R: | |
3767 | case BUILT_IN_GAMMAL_R: | |
3768 | case BUILT_IN_LGAMMA_R: | |
3769 | case BUILT_IN_LGAMMAF_R: | |
3770 | case BUILT_IN_LGAMMAL_R: | |
3771 | case BUILT_IN_MODF: | |
3772 | case BUILT_IN_MODFF: | |
3773 | case BUILT_IN_MODFL: | |
3774 | case BUILT_IN_REMQUO: | |
3775 | case BUILT_IN_REMQUOF: | |
3776 | case BUILT_IN_REMQUOL: | |
3777 | case BUILT_IN_FREE: | |
3778 | return; | |
3779 | /* printf-style functions may have hooks to set pointers to | |
3780 | point to somewhere into the generated string. Leave them | |
3781 | for a later excercise... */ | |
3782 | default: | |
3783 | /* Fallthru to general call handling. */; | |
3784 | } | |
5c245b95 RG |
3785 | if (!in_ipa_mode |
3786 | || (fndecl | |
3787 | && !lookup_vi_for_tree (fndecl))) | |
4ee00913 | 3788 | { |
472c7fbd | 3789 | VEC(ce_s, heap) *rhsc = NULL; |
726a989a RB |
3790 | int flags = gimple_call_flags (t); |
3791 | ||
b7091901 RG |
3792 | /* Const functions can return their arguments and addresses |
3793 | of global memory but not of escaped memory. */ | |
472c7fbd | 3794 | if (flags & (ECF_CONST|ECF_NOVOPS)) |
b7091901 | 3795 | { |
726a989a RB |
3796 | if (gimple_call_lhs (t) |
3797 | && could_have_pointers (gimple_call_lhs (t))) | |
472c7fbd | 3798 | handle_const_call (t, &rhsc); |
b7091901 | 3799 | } |
726a989a RB |
3800 | /* Pure functions can return addresses in and of memory |
3801 | reachable from their arguments, but they are not an escape | |
3802 | point for reachable memory of their arguments. */ | |
472c7fbd RG |
3803 | else if (flags & (ECF_PURE|ECF_LOOPING_CONST_OR_PURE)) |
3804 | handle_pure_call (t, &rhsc); | |
726a989a | 3805 | else |
472c7fbd RG |
3806 | handle_rhs_call (t, &rhsc); |
3807 | if (gimple_call_lhs (t) | |
3808 | && could_have_pointers (gimple_call_lhs (t))) | |
3809 | handle_lhs_call (gimple_call_lhs (t), flags, rhsc); | |
3810 | VEC_free (ce_s, heap, rhsc); | |
4ee00913 DB |
3811 | } |
3812 | else | |
3813 | { | |
7b765bed | 3814 | tree lhsop; |
7b765bed DB |
3815 | varinfo_t fi; |
3816 | int i = 1; | |
726a989a | 3817 | size_t j; |
7b765bed | 3818 | tree decl; |
726a989a RB |
3819 | |
3820 | lhsop = gimple_call_lhs (t); | |
3821 | decl = gimple_call_fndecl (t); | |
7b765bed DB |
3822 | |
3823 | /* If we can directly resolve the function being called, do so. | |
3824 | Otherwise, it must be some sort of indirect expression that | |
3825 | we should still be able to handle. */ | |
3826 | if (decl) | |
726a989a | 3827 | fi = get_vi_for_tree (decl); |
7b765bed DB |
3828 | else |
3829 | { | |
726a989a | 3830 | decl = gimple_call_fn (t); |
7b765bed | 3831 | fi = get_vi_for_tree (decl); |
4ee00913 | 3832 | } |
6e7e772d | 3833 | |
7b765bed DB |
3834 | /* Assign all the passed arguments to the appropriate incoming |
3835 | parameters of the function. */ | |
726a989a | 3836 | for (j = 0; j < gimple_call_num_args (t); j++) |
4ee00913 | 3837 | { |
7b765bed DB |
3838 | struct constraint_expr lhs ; |
3839 | struct constraint_expr *rhsp; | |
726a989a | 3840 | tree arg = gimple_call_arg (t, j); |
7b765bed DB |
3841 | |
3842 | get_constraint_for (arg, &rhsc); | |
3843 | if (TREE_CODE (decl) != FUNCTION_DECL) | |
3844 | { | |
3845 | lhs.type = DEREF; | |
3846 | lhs.var = fi->id; | |
3847 | lhs.offset = i; | |
3848 | } | |
3849 | else | |
3850 | { | |
3851 | lhs.type = SCALAR; | |
3852 | lhs.var = first_vi_for_offset (fi, i)->id; | |
3853 | lhs.offset = 0; | |
3854 | } | |
3855 | while (VEC_length (ce_s, rhsc) != 0) | |
3856 | { | |
3857 | rhsp = VEC_last (ce_s, rhsc); | |
3858 | process_constraint (new_constraint (lhs, *rhsp)); | |
3859 | VEC_pop (ce_s, rhsc); | |
3860 | } | |
3861 | i++; | |
4ee00913 | 3862 | } |
7b765bed DB |
3863 | |
3864 | /* If we are returning a value, assign it to the result. */ | |
3865 | if (lhsop) | |
4ee00913 | 3866 | { |
7b765bed DB |
3867 | struct constraint_expr rhs; |
3868 | struct constraint_expr *lhsp; | |
3869 | unsigned int j = 0; | |
3870 | ||
3871 | get_constraint_for (lhsop, &lhsc); | |
3872 | if (TREE_CODE (decl) != FUNCTION_DECL) | |
3873 | { | |
3874 | rhs.type = DEREF; | |
3875 | rhs.var = fi->id; | |
3876 | rhs.offset = i; | |
3877 | } | |
3878 | else | |
3879 | { | |
3880 | rhs.type = SCALAR; | |
3881 | rhs.var = first_vi_for_offset (fi, i)->id; | |
3882 | rhs.offset = 0; | |
3883 | } | |
3884 | for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++) | |
3885 | process_constraint (new_constraint (*lhsp, rhs)); | |
4ee00913 | 3886 | } |
c58936b6 | 3887 | } |
e8ca4159 | 3888 | } |
e5bae89b RG |
3889 | /* Otherwise, just a regular assignment statement. Only care about |
3890 | operations with pointer result, others are dealt with as escape | |
3891 | points if they have pointer operands. */ | |
726a989a RB |
3892 | else if (is_gimple_assign (t) |
3893 | && could_have_pointers (gimple_assign_lhs (t))) | |
e8ca4159 | 3894 | { |
726a989a RB |
3895 | /* Otherwise, just a regular assignment statement. */ |
3896 | tree lhsop = gimple_assign_lhs (t); | |
3897 | tree rhsop = (gimple_num_ops (t) == 2) ? gimple_assign_rhs1 (t) : NULL; | |
e8ca4159 | 3898 | |
726a989a | 3899 | if (rhsop && AGGREGATE_TYPE_P (TREE_TYPE (lhsop))) |
e5bae89b | 3900 | do_structure_copy (lhsop, rhsop); |
e8ca4159 DN |
3901 | else |
3902 | { | |
726a989a | 3903 | struct constraint_expr temp; |
e5bae89b | 3904 | get_constraint_for (lhsop, &lhsc); |
726a989a RB |
3905 | |
3906 | if (gimple_assign_rhs_code (t) == POINTER_PLUS_EXPR) | |
3907 | get_constraint_for_ptr_offset (gimple_assign_rhs1 (t), | |
3908 | gimple_assign_rhs2 (t), &rhsc); | |
1a87cf0c | 3909 | else if ((CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (t)) |
1961418e RG |
3910 | && !(POINTER_TYPE_P (gimple_expr_type (t)) |
3911 | && !POINTER_TYPE_P (TREE_TYPE (rhsop)))) | |
3912 | || gimple_assign_single_p (t)) | |
726a989a RB |
3913 | get_constraint_for (rhsop, &rhsc); |
3914 | else | |
3915 | { | |
3916 | temp.type = ADDRESSOF; | |
3917 | temp.var = anything_id; | |
3918 | temp.offset = 0; | |
3919 | VEC_safe_push (ce_s, heap, rhsc, &temp); | |
3920 | } | |
779704e7 | 3921 | process_all_all_constraints (lhsc, rhsc); |
e8ca4159 | 3922 | } |
de70bb20 RG |
3923 | /* If there is a store to a global variable the rhs escapes. */ |
3924 | if ((lhsop = get_base_address (lhsop)) != NULL_TREE | |
3925 | && DECL_P (lhsop) | |
3926 | && is_global_var (lhsop)) | |
3927 | make_escape_constraint (rhsop); | |
74d27244 RG |
3928 | /* If this is a conversion of a non-restrict pointer to a |
3929 | restrict pointer track it with a new heapvar. */ | |
3930 | else if (gimple_assign_cast_p (t) | |
3931 | && POINTER_TYPE_P (TREE_TYPE (rhsop)) | |
3932 | && POINTER_TYPE_P (TREE_TYPE (lhsop)) | |
3933 | && !TYPE_RESTRICT (TREE_TYPE (rhsop)) | |
3934 | && TYPE_RESTRICT (TREE_TYPE (lhsop))) | |
3935 | make_constraint_from_restrict (get_vi_for_tree (lhsop), | |
3936 | "CAST_RESTRICT"); | |
910fdc79 | 3937 | } |
2e407842 RG |
3938 | /* For conversions of pointers to non-pointers the pointer escapes. */ |
3939 | else if (gimple_assign_cast_p (t) | |
3940 | && POINTER_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (t))) | |
3941 | && !POINTER_TYPE_P (TREE_TYPE (gimple_assign_lhs (t)))) | |
b7091901 | 3942 | { |
726a989a | 3943 | make_escape_constraint (gimple_assign_rhs1 (t)); |
b7091901 | 3944 | } |
14c41b9b RG |
3945 | /* Handle escapes through return. */ |
3946 | else if (gimple_code (t) == GIMPLE_RETURN | |
3947 | && gimple_return_retval (t) != NULL_TREE | |
3948 | && could_have_pointers (gimple_return_retval (t))) | |
3949 | { | |
3950 | make_escape_constraint (gimple_return_retval (t)); | |
3951 | } | |
2e407842 RG |
3952 | /* Handle asms conservatively by adding escape constraints to everything. */ |
3953 | else if (gimple_code (t) == GIMPLE_ASM) | |
b7091901 | 3954 | { |
5006671f RG |
3955 | unsigned i, noutputs; |
3956 | const char **oconstraints; | |
3957 | const char *constraint; | |
3958 | bool allows_mem, allows_reg, is_inout; | |
3959 | ||
3960 | noutputs = gimple_asm_noutputs (t); | |
3961 | oconstraints = XALLOCAVEC (const char *, noutputs); | |
3962 | ||
3963 | for (i = 0; i < noutputs; ++i) | |
b7091901 | 3964 | { |
5006671f RG |
3965 | tree link = gimple_asm_output_op (t, i); |
3966 | tree op = TREE_VALUE (link); | |
3967 | ||
3968 | constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); | |
3969 | oconstraints[i] = constraint; | |
3970 | parse_output_constraint (&constraint, i, 0, 0, &allows_mem, | |
3971 | &allows_reg, &is_inout); | |
3972 | ||
3973 | /* A memory constraint makes the address of the operand escape. */ | |
3974 | if (!allows_reg && allows_mem) | |
3975 | make_escape_constraint (build_fold_addr_expr (op)); | |
3976 | ||
3977 | /* The asm may read global memory, so outputs may point to | |
3978 | any global memory. */ | |
b7091901 | 3979 | if (op && could_have_pointers (op)) |
5006671f RG |
3980 | { |
3981 | VEC(ce_s, heap) *lhsc = NULL; | |
3982 | struct constraint_expr rhsc, *lhsp; | |
3983 | unsigned j; | |
3984 | get_constraint_for (op, &lhsc); | |
3985 | rhsc.var = nonlocal_id; | |
3986 | rhsc.offset = 0; | |
3987 | rhsc.type = SCALAR; | |
3988 | for (j = 0; VEC_iterate (ce_s, lhsc, j, lhsp); j++) | |
3989 | process_constraint (new_constraint (*lhsp, rhsc)); | |
3990 | VEC_free (ce_s, heap, lhsc); | |
3991 | } | |
b7091901 | 3992 | } |
726a989a | 3993 | for (i = 0; i < gimple_asm_ninputs (t); ++i) |
b7091901 | 3994 | { |
5006671f RG |
3995 | tree link = gimple_asm_input_op (t, i); |
3996 | tree op = TREE_VALUE (link); | |
3997 | ||
3998 | constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); | |
3999 | ||
4000 | parse_input_constraint (&constraint, 0, 0, noutputs, 0, oconstraints, | |
4001 | &allows_mem, &allows_reg); | |
4002 | ||
4003 | /* A memory constraint makes the address of the operand escape. */ | |
4004 | if (!allows_reg && allows_mem) | |
4005 | make_escape_constraint (build_fold_addr_expr (op)); | |
4006 | /* Strictly we'd only need the constraint to ESCAPED if | |
4007 | the asm clobbers memory, otherwise using CALLUSED | |
4008 | would be enough. */ | |
4009 | else if (op && could_have_pointers (op)) | |
b7091901 RG |
4010 | make_escape_constraint (op); |
4011 | } | |
4012 | } | |
4013 | ||
4ee00913 DB |
4014 | VEC_free (ce_s, heap, rhsc); |
4015 | VEC_free (ce_s, heap, lhsc); | |
910fdc79 DB |
4016 | } |
4017 | ||
4018 | ||
4019 | /* Find the first varinfo in the same variable as START that overlaps with | |
5006671f | 4020 | OFFSET. Return NULL if we can't find one. */ |
910fdc79 | 4021 | |
c58936b6 | 4022 | static varinfo_t |
910fdc79 DB |
4023 | first_vi_for_offset (varinfo_t start, unsigned HOST_WIDE_INT offset) |
4024 | { | |
5006671f RG |
4025 | /* If the offset is outside of the variable, bail out. */ |
4026 | if (offset >= start->fullsize) | |
4027 | return NULL; | |
4028 | ||
4029 | /* If we cannot reach offset from start, lookup the first field | |
4030 | and start from there. */ | |
4031 | if (start->offset > offset) | |
4032 | start = lookup_vi_for_tree (start->decl); | |
4033 | ||
4034 | while (start) | |
910fdc79 DB |
4035 | { |
4036 | /* We may not find a variable in the field list with the actual | |
4037 | offset when when we have glommed a structure to a variable. | |
4038 | In that case, however, offset should still be within the size | |
4039 | of the variable. */ | |
5006671f | 4040 | if (offset >= start->offset |
de925a03 | 4041 | && (offset - start->offset) < start->size) |
5006671f RG |
4042 | return start; |
4043 | ||
4044 | start= start->next; | |
910fdc79 | 4045 | } |
5006671f | 4046 | |
8971094d | 4047 | return NULL; |
910fdc79 DB |
4048 | } |
4049 | ||
5006671f RG |
4050 | /* Find the first varinfo in the same variable as START that overlaps with |
4051 | OFFSET. If there is no such varinfo the varinfo directly preceding | |
4052 | OFFSET is returned. */ | |
4053 | ||
4054 | static varinfo_t | |
4055 | first_or_preceding_vi_for_offset (varinfo_t start, | |
4056 | unsigned HOST_WIDE_INT offset) | |
4057 | { | |
4058 | /* If we cannot reach offset from start, lookup the first field | |
4059 | and start from there. */ | |
4060 | if (start->offset > offset) | |
4061 | start = lookup_vi_for_tree (start->decl); | |
4062 | ||
4063 | /* We may not find a variable in the field list with the actual | |
4064 | offset when when we have glommed a structure to a variable. | |
4065 | In that case, however, offset should still be within the size | |
4066 | of the variable. | |
4067 | If we got beyond the offset we look for return the field | |
4068 | directly preceding offset which may be the last field. */ | |
4069 | while (start->next | |
4070 | && offset >= start->offset | |
de925a03 | 4071 | && !((offset - start->offset) < start->size)) |
5006671f RG |
4072 | start = start->next; |
4073 | ||
4074 | return start; | |
4075 | } | |
4076 | ||
910fdc79 | 4077 | |
4cf4d6a3 DB |
4078 | /* Insert the varinfo FIELD into the field list for BASE, at the front |
4079 | of the list. */ | |
4080 | ||
4081 | static void | |
4082 | insert_into_field_list (varinfo_t base, varinfo_t field) | |
4083 | { | |
4084 | varinfo_t prev = base; | |
4085 | varinfo_t curr = base->next; | |
c58936b6 | 4086 | |
4cf4d6a3 DB |
4087 | field->next = curr; |
4088 | prev->next = field; | |
4089 | } | |
4090 | ||
910fdc79 DB |
4091 | /* Insert the varinfo FIELD into the field list for BASE, ordered by |
4092 | offset. */ | |
4093 | ||
4094 | static void | |
4cf4d6a3 | 4095 | insert_into_field_list_sorted (varinfo_t base, varinfo_t field) |
910fdc79 DB |
4096 | { |
4097 | varinfo_t prev = base; | |
4098 | varinfo_t curr = base->next; | |
c58936b6 | 4099 | |
910fdc79 DB |
4100 | if (curr == NULL) |
4101 | { | |
4102 | prev->next = field; | |
4103 | field->next = NULL; | |
4104 | } | |
4105 | else | |
4106 | { | |
4107 | while (curr) | |
4108 | { | |
4109 | if (field->offset <= curr->offset) | |
4110 | break; | |
4111 | prev = curr; | |
4112 | curr = curr->next; | |
4113 | } | |
4114 | field->next = prev->next; | |
4115 | prev->next = field; | |
4116 | } | |
4117 | } | |
4118 | ||
31de5b77 RG |
4119 | /* This structure is used during pushing fields onto the fieldstack |
4120 | to track the offset of the field, since bitpos_of_field gives it | |
4121 | relative to its immediate containing type, and we want it relative | |
4122 | to the ultimate containing object. */ | |
4123 | ||
4124 | struct fieldoff | |
4125 | { | |
ee7d4b57 RG |
4126 | /* Offset from the base of the base containing object to this field. */ |
4127 | HOST_WIDE_INT offset; | |
31de5b77 RG |
4128 | |
4129 | /* Size, in bits, of the field. */ | |
ee7d4b57 | 4130 | unsigned HOST_WIDE_INT size; |
31de5b77 | 4131 | |
ee7d4b57 | 4132 | unsigned has_unknown_size : 1; |
31de5b77 | 4133 | |
ee7d4b57 | 4134 | unsigned may_have_pointers : 1; |
74d27244 RG |
4135 | |
4136 | unsigned only_restrict_pointers : 1; | |
31de5b77 RG |
4137 | }; |
4138 | typedef struct fieldoff fieldoff_s; | |
4139 | ||
4140 | DEF_VEC_O(fieldoff_s); | |
4141 | DEF_VEC_ALLOC_O(fieldoff_s,heap); | |
4142 | ||
910fdc79 DB |
4143 | /* qsort comparison function for two fieldoff's PA and PB */ |
4144 | ||
c58936b6 | 4145 | static int |
910fdc79 DB |
4146 | fieldoff_compare (const void *pa, const void *pb) |
4147 | { | |
4148 | const fieldoff_s *foa = (const fieldoff_s *)pa; | |
4149 | const fieldoff_s *fob = (const fieldoff_s *)pb; | |
185ab3b6 | 4150 | unsigned HOST_WIDE_INT foasize, fobsize; |
c58936b6 | 4151 | |
185ab3b6 RG |
4152 | if (foa->offset < fob->offset) |
4153 | return -1; | |
4154 | else if (foa->offset > fob->offset) | |
4155 | return 1; | |
910fdc79 | 4156 | |
ee7d4b57 RG |
4157 | foasize = foa->size; |
4158 | fobsize = fob->size; | |
185ab3b6 | 4159 | if (foasize < fobsize) |
ee7d4b57 | 4160 | return -1; |
185ab3b6 RG |
4161 | else if (foasize > fobsize) |
4162 | return 1; | |
4163 | return 0; | |
910fdc79 DB |
4164 | } |
4165 | ||
4166 | /* Sort a fieldstack according to the field offset and sizes. */ | |
31de5b77 | 4167 | static void |
83f676b3 | 4168 | sort_fieldstack (VEC(fieldoff_s,heap) *fieldstack) |
910fdc79 | 4169 | { |
c58936b6 DB |
4170 | qsort (VEC_address (fieldoff_s, fieldstack), |
4171 | VEC_length (fieldoff_s, fieldstack), | |
910fdc79 DB |
4172 | sizeof (fieldoff_s), |
4173 | fieldoff_compare); | |
4174 | } | |
4175 | ||
31de5b77 RG |
4176 | /* Return true if V is a tree that we can have subvars for. |
4177 | Normally, this is any aggregate type. Also complex | |
4178 | types which are not gimple registers can have subvars. */ | |
4179 | ||
4180 | static inline bool | |
4181 | var_can_have_subvars (const_tree v) | |
4182 | { | |
4183 | /* Volatile variables should never have subvars. */ | |
4184 | if (TREE_THIS_VOLATILE (v)) | |
4185 | return false; | |
4186 | ||
4187 | /* Non decls or memory tags can never have subvars. */ | |
5006671f | 4188 | if (!DECL_P (v)) |
31de5b77 RG |
4189 | return false; |
4190 | ||
4191 | /* Aggregates without overlapping fields can have subvars. */ | |
4192 | if (TREE_CODE (TREE_TYPE (v)) == RECORD_TYPE) | |
4193 | return true; | |
4194 | ||
4195 | return false; | |
4196 | } | |
4197 | ||
d7705551 DN |
4198 | /* Given a TYPE, and a vector of field offsets FIELDSTACK, push all |
4199 | the fields of TYPE onto fieldstack, recording their offsets along | |
4200 | the way. | |
4201 | ||
4202 | OFFSET is used to keep track of the offset in this entire | |
4203 | structure, rather than just the immediately containing structure. | |
ee7d4b57 | 4204 | Returns the number of fields pushed. */ |
910fdc79 | 4205 | |
31de5b77 | 4206 | static int |
c58936b6 | 4207 | push_fields_onto_fieldstack (tree type, VEC(fieldoff_s,heap) **fieldstack, |
ee7d4b57 | 4208 | HOST_WIDE_INT offset) |
910fdc79 DB |
4209 | { |
4210 | tree field; | |
4211 | int count = 0; | |
31de5b77 RG |
4212 | |
4213 | if (TREE_CODE (type) != RECORD_TYPE) | |
4214 | return 0; | |
3fe2f42a RG |
4215 | |
4216 | /* If the vector of fields is growing too big, bail out early. | |
4217 | Callers check for VEC_length <= MAX_FIELDS_FOR_FIELD_SENSITIVE, make | |
4218 | sure this fails. */ | |
31de5b77 | 4219 | if (VEC_length (fieldoff_s, *fieldstack) > MAX_FIELDS_FOR_FIELD_SENSITIVE) |
3fe2f42a | 4220 | return 0; |
c58936b6 | 4221 | |
31de5b77 RG |
4222 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) |
4223 | if (TREE_CODE (field) == FIELD_DECL) | |
4224 | { | |
4225 | bool push = false; | |
4226 | int pushed = 0; | |
ee7d4b57 | 4227 | HOST_WIDE_INT foff = bitpos_of_field (field); |
31de5b77 | 4228 | |
ee7d4b57 RG |
4229 | if (!var_can_have_subvars (field) |
4230 | || TREE_CODE (TREE_TYPE (field)) == QUAL_UNION_TYPE | |
4231 | || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE) | |
31de5b77 RG |
4232 | push = true; |
4233 | else if (!(pushed = push_fields_onto_fieldstack | |
ee7d4b57 | 4234 | (TREE_TYPE (field), fieldstack, offset + foff)) |
31de5b77 RG |
4235 | && (DECL_SIZE (field) |
4236 | && !integer_zerop (DECL_SIZE (field)))) | |
4237 | /* Empty structures may have actual size, like in C++. So | |
4238 | see if we didn't push any subfields and the size is | |
4239 | nonzero, push the field onto the stack. */ | |
4240 | push = true; | |
4241 | ||
4242 | if (push) | |
910fdc79 | 4243 | { |
ee7d4b57 RG |
4244 | fieldoff_s *pair = NULL; |
4245 | bool has_unknown_size = false; | |
4246 | ||
4247 | if (!VEC_empty (fieldoff_s, *fieldstack)) | |
4248 | pair = VEC_last (fieldoff_s, *fieldstack); | |
4249 | ||
4250 | if (!DECL_SIZE (field) | |
4251 | || !host_integerp (DECL_SIZE (field), 1)) | |
4252 | has_unknown_size = true; | |
4253 | ||
4254 | /* If adjacent fields do not contain pointers merge them. */ | |
4255 | if (pair | |
4256 | && !pair->may_have_pointers | |
4257 | && !could_have_pointers (field) | |
4258 | && !pair->has_unknown_size | |
4259 | && !has_unknown_size | |
4260 | && pair->offset + (HOST_WIDE_INT)pair->size == offset + foff) | |
4261 | { | |
4262 | pair = VEC_last (fieldoff_s, *fieldstack); | |
4263 | pair->size += TREE_INT_CST_LOW (DECL_SIZE (field)); | |
4264 | } | |
4265 | else | |
4266 | { | |
4267 | pair = VEC_safe_push (fieldoff_s, heap, *fieldstack, NULL); | |
4268 | pair->offset = offset + foff; | |
4269 | pair->has_unknown_size = has_unknown_size; | |
4270 | if (!has_unknown_size) | |
4271 | pair->size = TREE_INT_CST_LOW (DECL_SIZE (field)); | |
4272 | else | |
4273 | pair->size = -1; | |
4274 | pair->may_have_pointers = could_have_pointers (field); | |
74d27244 RG |
4275 | pair->only_restrict_pointers |
4276 | = (!has_unknown_size | |
4277 | && POINTER_TYPE_P (TREE_TYPE (field)) | |
4278 | && TYPE_RESTRICT (TREE_TYPE (field))); | |
ee7d4b57 RG |
4279 | count++; |
4280 | } | |
31de5b77 RG |
4281 | } |
4282 | else | |
4283 | count += pushed; | |
4284 | } | |
910fdc79 DB |
4285 | |
4286 | return count; | |
4287 | } | |
4288 | ||
5006671f RG |
4289 | /* Count the number of arguments DECL has, and set IS_VARARGS to true |
4290 | if it is a varargs function. */ | |
4291 | ||
4292 | static unsigned int | |
4293 | count_num_arguments (tree decl, bool *is_varargs) | |
4294 | { | |
de925a03 | 4295 | unsigned int num = 0; |
5006671f RG |
4296 | tree t; |
4297 | ||
de925a03 RG |
4298 | /* Capture named arguments for K&R functions. They do not |
4299 | have a prototype and thus no TYPE_ARG_TYPES. */ | |
4300 | for (t = DECL_ARGUMENTS (decl); t; t = TREE_CHAIN (t)) | |
4301 | ++num; | |
c58936b6 | 4302 | |
de925a03 RG |
4303 | /* Check if the function has variadic arguments. */ |
4304 | for (t = TYPE_ARG_TYPES (TREE_TYPE (decl)); t; t = TREE_CHAIN (t)) | |
4305 | if (TREE_VALUE (t) == void_type_node) | |
4306 | break; | |
4ee00913 DB |
4307 | if (!t) |
4308 | *is_varargs = true; | |
de925a03 RG |
4309 | |
4310 | return num; | |
4ee00913 DB |
4311 | } |
4312 | ||
4313 | /* Creation function node for DECL, using NAME, and return the index | |
4314 | of the variable we've created for the function. */ | |
4315 | ||
4316 | static unsigned int | |
4317 | create_function_info_for (tree decl, const char *name) | |
4318 | { | |
4ee00913 | 4319 | varinfo_t vi; |
c58936b6 | 4320 | tree arg; |
4ee00913 DB |
4321 | unsigned int i; |
4322 | bool is_varargs = false; | |
4323 | ||
4324 | /* Create the variable info. */ | |
4325 | ||
0bbf2ffa | 4326 | vi = new_var_info (decl, name); |
4ee00913 | 4327 | vi->offset = 0; |
4ee00913 DB |
4328 | vi->size = 1; |
4329 | vi->fullsize = count_num_arguments (decl, &is_varargs) + 1; | |
3e5937d7 | 4330 | insert_vi_for_tree (vi->decl, vi); |
4ee00913 DB |
4331 | |
4332 | stats.total_vars++; | |
4333 | ||
4334 | /* If it's varargs, we don't know how many arguments it has, so we | |
e5bae89b | 4335 | can't do much. */ |
4ee00913 DB |
4336 | if (is_varargs) |
4337 | { | |
4338 | vi->fullsize = ~0; | |
4339 | vi->size = ~0; | |
4340 | vi->is_unknown_size_var = true; | |
0bbf2ffa | 4341 | return vi->id; |
4ee00913 DB |
4342 | } |
4343 | ||
4ee00913 DB |
4344 | arg = DECL_ARGUMENTS (decl); |
4345 | ||
6416ae7f | 4346 | /* Set up variables for each argument. */ |
4ee00913 | 4347 | for (i = 1; i < vi->fullsize; i++) |
c58936b6 | 4348 | { |
4ee00913 DB |
4349 | varinfo_t argvi; |
4350 | const char *newname; | |
4351 | char *tempname; | |
4ee00913 DB |
4352 | tree argdecl = decl; |
4353 | ||
4354 | if (arg) | |
4355 | argdecl = arg; | |
c58936b6 | 4356 | |
4ee00913 DB |
4357 | asprintf (&tempname, "%s.arg%d", name, i-1); |
4358 | newname = ggc_strdup (tempname); | |
4359 | free (tempname); | |
4360 | ||
0bbf2ffa | 4361 | argvi = new_var_info (argdecl, newname); |
4ee00913 DB |
4362 | argvi->offset = i; |
4363 | argvi->size = 1; | |
e5bae89b | 4364 | argvi->is_full_var = true; |
4ee00913 | 4365 | argvi->fullsize = vi->fullsize; |
4cf4d6a3 | 4366 | insert_into_field_list_sorted (vi, argvi); |
4ee00913 DB |
4367 | stats.total_vars ++; |
4368 | if (arg) | |
4369 | { | |
3e5937d7 | 4370 | insert_vi_for_tree (arg, argvi); |
4ee00913 DB |
4371 | arg = TREE_CHAIN (arg); |
4372 | } | |
4373 | } | |
4cf4d6a3 | 4374 | |
4ee00913 DB |
4375 | /* Create a variable for the return var. */ |
4376 | if (DECL_RESULT (decl) != NULL | |
4377 | || !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl)))) | |
4378 | { | |
4379 | varinfo_t resultvi; | |
4380 | const char *newname; | |
4381 | char *tempname; | |
4ee00913 DB |
4382 | tree resultdecl = decl; |
4383 | ||
4384 | vi->fullsize ++; | |
4385 | ||
4ee00913 DB |
4386 | if (DECL_RESULT (decl)) |
4387 | resultdecl = DECL_RESULT (decl); | |
c58936b6 | 4388 | |
4ee00913 DB |
4389 | asprintf (&tempname, "%s.result", name); |
4390 | newname = ggc_strdup (tempname); | |
4391 | free (tempname); | |
4392 | ||
0bbf2ffa | 4393 | resultvi = new_var_info (resultdecl, newname); |
4ee00913 DB |
4394 | resultvi->offset = i; |
4395 | resultvi->size = 1; | |
4396 | resultvi->fullsize = vi->fullsize; | |
e5bae89b | 4397 | resultvi->is_full_var = true; |
4cf4d6a3 | 4398 | insert_into_field_list_sorted (vi, resultvi); |
4ee00913 DB |
4399 | stats.total_vars ++; |
4400 | if (DECL_RESULT (decl)) | |
3e5937d7 | 4401 | insert_vi_for_tree (DECL_RESULT (decl), resultvi); |
4ee00913 | 4402 | } |
0bbf2ffa RG |
4403 | |
4404 | return vi->id; | |
c58936b6 | 4405 | } |
4ee00913 | 4406 | |
6c11790d | 4407 | |
c58936b6 | 4408 | /* Return true if FIELDSTACK contains fields that overlap. |
6c11790d DB |
4409 | FIELDSTACK is assumed to be sorted by offset. */ |
4410 | ||
4411 | static bool | |
4412 | check_for_overlaps (VEC (fieldoff_s,heap) *fieldstack) | |
4413 | { | |
4414 | fieldoff_s *fo = NULL; | |
4415 | unsigned int i; | |
30d2662c | 4416 | HOST_WIDE_INT lastoffset = -1; |
6c11790d DB |
4417 | |
4418 | for (i = 0; VEC_iterate (fieldoff_s, fieldstack, i, fo); i++) | |
4419 | { | |
4420 | if (fo->offset == lastoffset) | |
4421 | return true; | |
4422 | lastoffset = fo->offset; | |
4423 | } | |
4424 | return false; | |
4425 | } | |
21392f19 | 4426 | |
910fdc79 DB |
4427 | /* Create a varinfo structure for NAME and DECL, and add it to VARMAP. |
4428 | This will also create any varinfo structures necessary for fields | |
4429 | of DECL. */ | |
4430 | ||
4431 | static unsigned int | |
4432 | create_variable_info_for (tree decl, const char *name) | |
4433 | { | |
910fdc79 | 4434 | varinfo_t vi; |
82d6e6fc KG |
4435 | tree decl_type = TREE_TYPE (decl); |
4436 | tree declsize = DECL_P (decl) ? DECL_SIZE (decl) : TYPE_SIZE (decl_type); | |
910fdc79 | 4437 | VEC (fieldoff_s,heap) *fieldstack = NULL; |
c58936b6 | 4438 | |
74d27244 | 4439 | if (var_can_have_subvars (decl) && use_field_sensitive) |
82d6e6fc | 4440 | push_fields_onto_fieldstack (decl_type, &fieldstack, 0); |
c58936b6 | 4441 | |
910fdc79 DB |
4442 | /* If the variable doesn't have subvars, we may end up needing to |
4443 | sort the field list and create fake variables for all the | |
4444 | fields. */ | |
0bbf2ffa | 4445 | vi = new_var_info (decl, name); |
910fdc79 | 4446 | vi->offset = 0; |
9e39dba6 | 4447 | vi->may_have_pointers = could_have_pointers (decl); |
4ee00913 | 4448 | if (!declsize |
ee7d4b57 | 4449 | || !host_integerp (declsize, 1)) |
910fdc79 DB |
4450 | { |
4451 | vi->is_unknown_size_var = true; | |
4452 | vi->fullsize = ~0; | |
4453 | vi->size = ~0; | |
4454 | } | |
4455 | else | |
4456 | { | |
4ee00913 | 4457 | vi->fullsize = TREE_INT_CST_LOW (declsize); |
910fdc79 DB |
4458 | vi->size = vi->fullsize; |
4459 | } | |
c58936b6 | 4460 | |
3e5937d7 | 4461 | insert_vi_for_tree (vi->decl, vi); |
74d27244 RG |
4462 | if (vi->is_global_var |
4463 | && (!flag_whole_program || !in_ipa_mode) | |
9e39dba6 | 4464 | && vi->may_have_pointers) |
13c6bff4 | 4465 | { |
74d27244 RG |
4466 | if (POINTER_TYPE_P (TREE_TYPE (decl)) |
4467 | && TYPE_RESTRICT (TREE_TYPE (decl))) | |
4468 | make_constraint_from_restrict (vi, "GLOBAL_RESTRICT"); | |
4469 | make_copy_constraint (vi, nonlocal_id); | |
13c6bff4 | 4470 | } |
910fdc79 DB |
4471 | |
4472 | stats.total_vars++; | |
c58936b6 | 4473 | if (use_field_sensitive |
c58936b6 | 4474 | && !vi->is_unknown_size_var |
98035a75 | 4475 | && var_can_have_subvars (decl) |
11948f6b | 4476 | && VEC_length (fieldoff_s, fieldstack) > 1 |
98035a75 | 4477 | && VEC_length (fieldoff_s, fieldstack) <= MAX_FIELDS_FOR_FIELD_SENSITIVE) |
910fdc79 | 4478 | { |
910fdc79 | 4479 | fieldoff_s *fo = NULL; |
ee7d4b57 | 4480 | bool notokay = false; |
910fdc79 | 4481 | unsigned int i; |
910fdc79 DB |
4482 | |
4483 | for (i = 0; !notokay && VEC_iterate (fieldoff_s, fieldstack, i, fo); i++) | |
4484 | { | |
ee7d4b57 | 4485 | if (fo->has_unknown_size |
910fdc79 DB |
4486 | || fo->offset < 0) |
4487 | { | |
4488 | notokay = true; | |
4489 | break; | |
4490 | } | |
4491 | } | |
58b82d2b DB |
4492 | |
4493 | /* We can't sort them if we have a field with a variable sized type, | |
4494 | which will make notokay = true. In that case, we are going to return | |
4495 | without creating varinfos for the fields anyway, so sorting them is a | |
4496 | waste to boot. */ | |
6c11790d | 4497 | if (!notokay) |
c58936b6 | 4498 | { |
6c11790d DB |
4499 | sort_fieldstack (fieldstack); |
4500 | /* Due to some C++ FE issues, like PR 22488, we might end up | |
4501 | what appear to be overlapping fields even though they, | |
4502 | in reality, do not overlap. Until the C++ FE is fixed, | |
4503 | we will simply disable field-sensitivity for these cases. */ | |
4504 | notokay = check_for_overlaps (fieldstack); | |
4505 | } | |
c58936b6 DB |
4506 | |
4507 | ||
910fdc79 DB |
4508 | if (VEC_length (fieldoff_s, fieldstack) != 0) |
4509 | fo = VEC_index (fieldoff_s, fieldstack, 0); | |
4510 | ||
4511 | if (fo == NULL || notokay) | |
4512 | { | |
4513 | vi->is_unknown_size_var = 1; | |
4514 | vi->fullsize = ~0; | |
4515 | vi->size = ~0; | |
e5bae89b | 4516 | vi->is_full_var = true; |
910fdc79 | 4517 | VEC_free (fieldoff_s, heap, fieldstack); |
0bbf2ffa | 4518 | return vi->id; |
910fdc79 | 4519 | } |
c58936b6 | 4520 | |
ee7d4b57 | 4521 | vi->size = fo->size; |
046a69e0 | 4522 | vi->offset = fo->offset; |
9e39dba6 | 4523 | vi->may_have_pointers = fo->may_have_pointers; |
10174ddf MM |
4524 | if (vi->is_global_var |
4525 | && (!flag_whole_program || !in_ipa_mode) | |
4526 | && vi->may_have_pointers) | |
4527 | { | |
4528 | if (fo->only_restrict_pointers) | |
4529 | make_constraint_from_restrict (vi, "GLOBAL_RESTRICT"); | |
4530 | } | |
c58936b6 DB |
4531 | for (i = VEC_length (fieldoff_s, fieldstack) - 1; |
4532 | i >= 1 && VEC_iterate (fieldoff_s, fieldstack, i, fo); | |
4cf4d6a3 | 4533 | i--) |
910fdc79 DB |
4534 | { |
4535 | varinfo_t newvi; | |
4f6c9110 | 4536 | const char *newname = "NULL"; |
910fdc79 DB |
4537 | char *tempname; |
4538 | ||
4f6c9110 RG |
4539 | if (dump_file) |
4540 | { | |
ee7d4b57 RG |
4541 | asprintf (&tempname, "%s." HOST_WIDE_INT_PRINT_DEC |
4542 | "+" HOST_WIDE_INT_PRINT_DEC, | |
4543 | vi->name, fo->offset, fo->size); | |
4f6c9110 RG |
4544 | newname = ggc_strdup (tempname); |
4545 | free (tempname); | |
4546 | } | |
0bbf2ffa | 4547 | newvi = new_var_info (decl, newname); |
910fdc79 | 4548 | newvi->offset = fo->offset; |
ee7d4b57 | 4549 | newvi->size = fo->size; |
910fdc79 | 4550 | newvi->fullsize = vi->fullsize; |
9e39dba6 | 4551 | newvi->may_have_pointers = fo->may_have_pointers; |
910fdc79 | 4552 | insert_into_field_list (vi, newvi); |
bacd3fb6 | 4553 | if ((newvi->is_global_var || TREE_CODE (decl) == PARM_DECL) |
9e39dba6 | 4554 | && newvi->may_have_pointers) |
74d27244 RG |
4555 | { |
4556 | if (fo->only_restrict_pointers) | |
4557 | make_constraint_from_restrict (newvi, "GLOBAL_RESTRICT"); | |
bacd3fb6 RG |
4558 | if (newvi->is_global_var && !in_ipa_mode) |
4559 | make_copy_constraint (newvi, nonlocal_id); | |
74d27244 | 4560 | } |
c58936b6 | 4561 | |
4ee00913 | 4562 | stats.total_vars++; |
910fdc79 | 4563 | } |
910fdc79 | 4564 | } |
e5bae89b RG |
4565 | else |
4566 | vi->is_full_var = true; | |
efe9e829 RG |
4567 | |
4568 | VEC_free (fieldoff_s, heap, fieldstack); | |
4569 | ||
0bbf2ffa | 4570 | return vi->id; |
910fdc79 DB |
4571 | } |
4572 | ||
4573 | /* Print out the points-to solution for VAR to FILE. */ | |
4574 | ||
5006671f | 4575 | static void |
910fdc79 DB |
4576 | dump_solution_for_var (FILE *file, unsigned int var) |
4577 | { | |
4578 | varinfo_t vi = get_varinfo (var); | |
4579 | unsigned int i; | |
c58936b6 DB |
4580 | bitmap_iterator bi; |
4581 | ||
3e5937d7 | 4582 | if (find (var) != var) |
910fdc79 | 4583 | { |
3e5937d7 | 4584 | varinfo_t vipt = get_varinfo (find (var)); |
c58936b6 DB |
4585 | fprintf (file, "%s = same as %s\n", vi->name, vipt->name); |
4586 | } | |
4587 | else | |
4588 | { | |
4589 | fprintf (file, "%s = { ", vi->name); | |
3e5937d7 | 4590 | EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi) |
c58936b6 DB |
4591 | { |
4592 | fprintf (file, "%s ", get_varinfo (i)->name); | |
4593 | } | |
4d7a65ea | 4594 | fprintf (file, "}\n"); |
910fdc79 | 4595 | } |
910fdc79 DB |
4596 | } |
4597 | ||
4598 | /* Print the points-to solution for VAR to stdout. */ | |
4599 | ||
4600 | void | |
4601 | debug_solution_for_var (unsigned int var) | |
4602 | { | |
4603 | dump_solution_for_var (stdout, var); | |
4604 | } | |
4605 | ||
910fdc79 DB |
4606 | /* Create varinfo structures for all of the variables in the |
4607 | function for intraprocedural mode. */ | |
4608 | ||
4609 | static void | |
4610 | intra_create_variable_infos (void) | |
4611 | { | |
4612 | tree t; | |
b23987ec | 4613 | |
6e7e772d | 4614 | /* For each incoming pointer argument arg, create the constraint ARG |
b7091901 | 4615 | = NONLOCAL or a dummy variable if flag_argument_noalias is set. */ |
910fdc79 DB |
4616 | for (t = DECL_ARGUMENTS (current_function_decl); t; t = TREE_CHAIN (t)) |
4617 | { | |
910fdc79 | 4618 | varinfo_t p; |
c58936b6 | 4619 | |
21392f19 DB |
4620 | if (!could_have_pointers (t)) |
4621 | continue; | |
c58936b6 | 4622 | |
bacd3fb6 RG |
4623 | /* For restrict qualified pointers to objects passed by |
4624 | reference build a real representative for the pointed-to object. */ | |
4625 | if (DECL_BY_REFERENCE (t) | |
4626 | && POINTER_TYPE_P (TREE_TYPE (t)) | |
4627 | && TYPE_RESTRICT (TREE_TYPE (t))) | |
4628 | { | |
4629 | struct constraint_expr lhsc, rhsc; | |
4630 | varinfo_t vi; | |
4631 | tree heapvar = heapvar_lookup (t, 0); | |
4632 | if (heapvar == NULL_TREE) | |
4633 | { | |
4634 | var_ann_t ann; | |
4635 | heapvar = create_tmp_var_raw (TREE_TYPE (TREE_TYPE (t)), | |
4636 | "PARM_NOALIAS"); | |
4637 | DECL_EXTERNAL (heapvar) = 1; | |
4638 | heapvar_insert (t, 0, heapvar); | |
4639 | ann = get_var_ann (heapvar); | |
4640 | ann->is_heapvar = 1; | |
4641 | } | |
4642 | if (gimple_referenced_vars (cfun)) | |
4643 | add_referenced_var (heapvar); | |
4644 | lhsc.var = get_vi_for_tree (t)->id; | |
4645 | lhsc.type = SCALAR; | |
4646 | lhsc.offset = 0; | |
4647 | rhsc.var = (vi = get_vi_for_tree (heapvar))->id; | |
4648 | rhsc.type = ADDRESSOF; | |
4649 | rhsc.offset = 0; | |
4650 | process_constraint (new_constraint (lhsc, rhsc)); | |
4651 | vi->is_restrict_var = 1; | |
4652 | continue; | |
4653 | } | |
4654 | ||
10174ddf | 4655 | for (p = get_vi_for_tree (t); p; p = p->next) |
bacd3fb6 RG |
4656 | if (p->may_have_pointers) |
4657 | make_constraint_from (p, nonlocal_id); | |
74d27244 RG |
4658 | if (POINTER_TYPE_P (TREE_TYPE (t)) |
4659 | && TYPE_RESTRICT (TREE_TYPE (t))) | |
4660 | make_constraint_from_restrict (get_vi_for_tree (t), "PARM_RESTRICT"); | |
21392f19 | 4661 | } |
75af9746 | 4662 | |
10bd6c5c RG |
4663 | /* Add a constraint for a result decl that is passed by reference. */ |
4664 | if (DECL_RESULT (cfun->decl) | |
4665 | && DECL_BY_REFERENCE (DECL_RESULT (cfun->decl))) | |
4666 | { | |
4667 | varinfo_t p, result_vi = get_vi_for_tree (DECL_RESULT (cfun->decl)); | |
4668 | ||
4669 | for (p = result_vi; p; p = p->next) | |
5006671f | 4670 | make_constraint_from (p, nonlocal_id); |
10bd6c5c RG |
4671 | } |
4672 | ||
75af9746 RG |
4673 | /* Add a constraint for the incoming static chain parameter. */ |
4674 | if (cfun->static_chain_decl != NULL_TREE) | |
4675 | { | |
4676 | varinfo_t p, chain_vi = get_vi_for_tree (cfun->static_chain_decl); | |
4677 | ||
4678 | for (p = chain_vi; p; p = p->next) | |
4679 | make_constraint_from (p, nonlocal_id); | |
4680 | } | |
910fdc79 DB |
4681 | } |
4682 | ||
1296c31f DB |
4683 | /* Structure used to put solution bitmaps in a hashtable so they can |
4684 | be shared among variables with the same points-to set. */ | |
4685 | ||
4686 | typedef struct shared_bitmap_info | |
4687 | { | |
4688 | bitmap pt_vars; | |
4689 | hashval_t hashcode; | |
4690 | } *shared_bitmap_info_t; | |
e5cfc29f | 4691 | typedef const struct shared_bitmap_info *const_shared_bitmap_info_t; |
1296c31f DB |
4692 | |
4693 | static htab_t shared_bitmap_table; | |
4694 | ||
4695 | /* Hash function for a shared_bitmap_info_t */ | |
4696 | ||
4697 | static hashval_t | |
4698 | shared_bitmap_hash (const void *p) | |
4699 | { | |
e5cfc29f | 4700 | const_shared_bitmap_info_t const bi = (const_shared_bitmap_info_t) p; |
1296c31f DB |
4701 | return bi->hashcode; |
4702 | } | |
4703 | ||
4704 | /* Equality function for two shared_bitmap_info_t's. */ | |
4705 | ||
4706 | static int | |
4707 | shared_bitmap_eq (const void *p1, const void *p2) | |
4708 | { | |
e5cfc29f KG |
4709 | const_shared_bitmap_info_t const sbi1 = (const_shared_bitmap_info_t) p1; |
4710 | const_shared_bitmap_info_t const sbi2 = (const_shared_bitmap_info_t) p2; | |
1296c31f DB |
4711 | return bitmap_equal_p (sbi1->pt_vars, sbi2->pt_vars); |
4712 | } | |
4713 | ||
4714 | /* Lookup a bitmap in the shared bitmap hashtable, and return an already | |
4715 | existing instance if there is one, NULL otherwise. */ | |
4716 | ||
4717 | static bitmap | |
4718 | shared_bitmap_lookup (bitmap pt_vars) | |
4719 | { | |
4720 | void **slot; | |
4721 | struct shared_bitmap_info sbi; | |
4722 | ||
4723 | sbi.pt_vars = pt_vars; | |
4724 | sbi.hashcode = bitmap_hash (pt_vars); | |
7b765bed | 4725 | |
1296c31f DB |
4726 | slot = htab_find_slot_with_hash (shared_bitmap_table, &sbi, |
4727 | sbi.hashcode, NO_INSERT); | |
4728 | if (!slot) | |
4729 | return NULL; | |
4730 | else | |
4731 | return ((shared_bitmap_info_t) *slot)->pt_vars; | |
4732 | } | |
4733 | ||
4734 | ||
4735 | /* Add a bitmap to the shared bitmap hashtable. */ | |
4736 | ||
4737 | static void | |
4738 | shared_bitmap_add (bitmap pt_vars) | |
4739 | { | |
4740 | void **slot; | |
4741 | shared_bitmap_info_t sbi = XNEW (struct shared_bitmap_info); | |
7b765bed | 4742 | |
1296c31f DB |
4743 | sbi->pt_vars = pt_vars; |
4744 | sbi->hashcode = bitmap_hash (pt_vars); | |
7b765bed | 4745 | |
1296c31f DB |
4746 | slot = htab_find_slot_with_hash (shared_bitmap_table, sbi, |
4747 | sbi->hashcode, INSERT); | |
4748 | gcc_assert (!*slot); | |
4749 | *slot = (void *) sbi; | |
4750 | } | |
4751 | ||
4752 | ||
4d7a65ea | 4753 | /* Set bits in INTO corresponding to the variable uids in solution set FROM. */ |
910fdc79 | 4754 | |
b8698a0f | 4755 | static void |
4d7a65ea | 4756 | set_uids_in_ptset (bitmap into, bitmap from, struct pt_solution *pt) |
910fdc79 DB |
4757 | { |
4758 | unsigned int i; | |
4759 | bitmap_iterator bi; | |
f83ca251 | 4760 | |
910fdc79 DB |
4761 | EXECUTE_IF_SET_IN_BITMAP (from, 0, i, bi) |
4762 | { | |
4763 | varinfo_t vi = get_varinfo (i); | |
c58936b6 | 4764 | |
e8ca4159 DN |
4765 | /* The only artificial variables that are allowed in a may-alias |
4766 | set are heap variables. */ | |
4767 | if (vi->is_artificial_var && !vi->is_heap_var) | |
4768 | continue; | |
c58936b6 | 4769 | |
5611cf0b RG |
4770 | if (TREE_CODE (vi->decl) == VAR_DECL |
4771 | || TREE_CODE (vi->decl) == PARM_DECL | |
4772 | || TREE_CODE (vi->decl) == RESULT_DECL) | |
58b82d2b | 4773 | { |
5006671f RG |
4774 | /* Add the decl to the points-to set. Note that the points-to |
4775 | set contains global variables. */ | |
4776 | bitmap_set_bit (into, DECL_UID (vi->decl)); | |
74d27244 | 4777 | if (vi->is_global_var) |
5006671f | 4778 | pt->vars_contains_global = true; |
e8ca4159 | 4779 | } |
910fdc79 DB |
4780 | } |
4781 | } | |
e8ca4159 DN |
4782 | |
4783 | ||
4d7a65ea | 4784 | /* Compute the points-to solution *PT for the variable VI. */ |
ce1b6498 RG |
4785 | |
4786 | static void | |
4d7a65ea | 4787 | find_what_var_points_to (varinfo_t vi, struct pt_solution *pt) |
ce1b6498 | 4788 | { |
4d7a65ea | 4789 | unsigned int i; |
5006671f RG |
4790 | bitmap_iterator bi; |
4791 | bitmap finished_solution; | |
4792 | bitmap result; | |
5006671f RG |
4793 | |
4794 | memset (pt, 0, sizeof (struct pt_solution)); | |
4795 | ||
4796 | /* This variable may have been collapsed, let's get the real | |
4797 | variable. */ | |
4798 | vi = get_varinfo (find (vi->id)); | |
4799 | ||
4800 | /* Translate artificial variables into SSA_NAME_PTR_INFO | |
4801 | attributes. */ | |
4802 | EXECUTE_IF_SET_IN_BITMAP (vi->solution, 0, i, bi) | |
4803 | { | |
4804 | varinfo_t vi = get_varinfo (i); | |
4805 | ||
4806 | if (vi->is_artificial_var) | |
4807 | { | |
4808 | if (vi->id == nothing_id) | |
4809 | pt->null = 1; | |
4810 | else if (vi->id == escaped_id) | |
4811 | pt->escaped = 1; | |
4812 | else if (vi->id == callused_id) | |
4813 | gcc_unreachable (); | |
4814 | else if (vi->id == nonlocal_id) | |
4815 | pt->nonlocal = 1; | |
4816 | else if (vi->is_heap_var) | |
4817 | /* We represent heapvars in the points-to set properly. */ | |
4818 | ; | |
91deb937 RG |
4819 | else if (vi->id == readonly_id) |
4820 | /* Nobody cares. */ | |
4821 | ; | |
5006671f | 4822 | else if (vi->id == anything_id |
5006671f RG |
4823 | || vi->id == integer_id) |
4824 | pt->anything = 1; | |
4825 | } | |
74d27244 RG |
4826 | if (vi->is_restrict_var) |
4827 | pt->vars_contains_restrict = true; | |
5006671f RG |
4828 | } |
4829 | ||
4830 | /* Instead of doing extra work, simply do not create | |
4831 | elaborate points-to information for pt_anything pointers. */ | |
74d27244 RG |
4832 | if (pt->anything |
4833 | && (vi->is_artificial_var | |
4834 | || !pt->vars_contains_restrict)) | |
4d7a65ea | 4835 | return; |
5006671f RG |
4836 | |
4837 | /* Share the final set of variables when possible. */ | |
4838 | finished_solution = BITMAP_GGC_ALLOC (); | |
4839 | stats.points_to_sets_created++; | |
4840 | ||
4d7a65ea | 4841 | set_uids_in_ptset (finished_solution, vi->solution, pt); |
5006671f RG |
4842 | result = shared_bitmap_lookup (finished_solution); |
4843 | if (!result) | |
4844 | { | |
4845 | shared_bitmap_add (finished_solution); | |
4846 | pt->vars = finished_solution; | |
4847 | } | |
4848 | else | |
4849 | { | |
4850 | pt->vars = result; | |
4851 | bitmap_clear (finished_solution); | |
4852 | } | |
5006671f RG |
4853 | } |
4854 | ||
4d7a65ea | 4855 | /* Given a pointer variable P, fill in its points-to set. */ |
5006671f RG |
4856 | |
4857 | static void | |
4d7a65ea | 4858 | find_what_p_points_to (tree p) |
5006671f RG |
4859 | { |
4860 | struct ptr_info_def *pi; | |
7cc92f92 | 4861 | tree lookup_p = p; |
3e5937d7 | 4862 | varinfo_t vi; |
e8ca4159 | 4863 | |
7cc92f92 RG |
4864 | /* For parameters, get at the points-to set for the actual parm |
4865 | decl. */ | |
c58936b6 DB |
4866 | if (TREE_CODE (p) == SSA_NAME |
4867 | && TREE_CODE (SSA_NAME_VAR (p)) == PARM_DECL | |
38635499 | 4868 | && SSA_NAME_IS_DEFAULT_DEF (p)) |
7cc92f92 RG |
4869 | lookup_p = SSA_NAME_VAR (p); |
4870 | ||
15814ba0 | 4871 | vi = lookup_vi_for_tree (lookup_p); |
5006671f RG |
4872 | if (!vi) |
4873 | return; | |
4874 | ||
4875 | pi = get_ptr_info (p); | |
4d7a65ea | 4876 | find_what_var_points_to (vi, &pi->pt); |
5006671f | 4877 | } |
7b765bed | 4878 | |
910fdc79 | 4879 | |
5006671f | 4880 | /* Query statistics for points-to solutions. */ |
c58936b6 | 4881 | |
5006671f RG |
4882 | static struct { |
4883 | unsigned HOST_WIDE_INT pt_solution_includes_may_alias; | |
4884 | unsigned HOST_WIDE_INT pt_solution_includes_no_alias; | |
4885 | unsigned HOST_WIDE_INT pt_solutions_intersect_may_alias; | |
4886 | unsigned HOST_WIDE_INT pt_solutions_intersect_no_alias; | |
4887 | } pta_stats; | |
e8ca4159 | 4888 | |
5006671f RG |
4889 | void |
4890 | dump_pta_stats (FILE *s) | |
4891 | { | |
4892 | fprintf (s, "\nPTA query stats:\n"); | |
4893 | fprintf (s, " pt_solution_includes: " | |
4894 | HOST_WIDE_INT_PRINT_DEC" disambiguations, " | |
4895 | HOST_WIDE_INT_PRINT_DEC" queries\n", | |
4896 | pta_stats.pt_solution_includes_no_alias, | |
4897 | pta_stats.pt_solution_includes_no_alias | |
4898 | + pta_stats.pt_solution_includes_may_alias); | |
4899 | fprintf (s, " pt_solutions_intersect: " | |
4900 | HOST_WIDE_INT_PRINT_DEC" disambiguations, " | |
4901 | HOST_WIDE_INT_PRINT_DEC" queries\n", | |
4902 | pta_stats.pt_solutions_intersect_no_alias, | |
4903 | pta_stats.pt_solutions_intersect_no_alias | |
4904 | + pta_stats.pt_solutions_intersect_may_alias); | |
4905 | } | |
e8ca4159 | 4906 | |
9f09b13f | 4907 | |
5006671f RG |
4908 | /* Reset the points-to solution *PT to a conservative default |
4909 | (point to anything). */ | |
7b765bed | 4910 | |
5006671f RG |
4911 | void |
4912 | pt_solution_reset (struct pt_solution *pt) | |
4913 | { | |
4914 | memset (pt, 0, sizeof (struct pt_solution)); | |
4915 | pt->anything = true; | |
4916 | } | |
1296c31f | 4917 | |
55b34b5f RG |
4918 | /* Set the points-to solution *PT to point only to the variables |
4919 | in VARS. */ | |
4920 | ||
4921 | void | |
4922 | pt_solution_set (struct pt_solution *pt, bitmap vars) | |
4923 | { | |
4924 | bitmap_iterator bi; | |
4925 | unsigned i; | |
4926 | ||
4927 | memset (pt, 0, sizeof (struct pt_solution)); | |
4928 | pt->vars = vars; | |
4929 | EXECUTE_IF_SET_IN_BITMAP (vars, 0, i, bi) | |
4930 | { | |
4931 | tree var = referenced_var_lookup (i); | |
4932 | if (is_global_var (var)) | |
4933 | { | |
4934 | pt->vars_contains_global = true; | |
4935 | break; | |
4936 | } | |
4937 | } | |
4938 | } | |
4939 | ||
5006671f | 4940 | /* Return true if the points-to solution *PT is empty. */ |
e8ca4159 | 4941 | |
5006671f RG |
4942 | static bool |
4943 | pt_solution_empty_p (struct pt_solution *pt) | |
4944 | { | |
4945 | if (pt->anything | |
4946 | || pt->nonlocal) | |
4947 | return false; | |
e8ca4159 | 4948 | |
5006671f RG |
4949 | if (pt->vars |
4950 | && !bitmap_empty_p (pt->vars)) | |
4951 | return false; | |
e8ca4159 | 4952 | |
5006671f RG |
4953 | /* If the solution includes ESCAPED, check if that is empty. */ |
4954 | if (pt->escaped | |
4955 | && !pt_solution_empty_p (&cfun->gimple_df->escaped)) | |
4956 | return false; | |
4957 | ||
4958 | return true; | |
910fdc79 DB |
4959 | } |
4960 | ||
5006671f | 4961 | /* Return true if the points-to solution *PT includes global memory. */ |
63a4ef6f | 4962 | |
2f571334 | 4963 | bool |
5006671f | 4964 | pt_solution_includes_global (struct pt_solution *pt) |
2f571334 | 4965 | { |
5006671f RG |
4966 | if (pt->anything |
4967 | || pt->nonlocal | |
4968 | || pt->vars_contains_global) | |
4969 | return true; | |
2f571334 | 4970 | |
5006671f RG |
4971 | if (pt->escaped) |
4972 | return pt_solution_includes_global (&cfun->gimple_df->escaped); | |
2f571334 | 4973 | |
5006671f RG |
4974 | return false; |
4975 | } | |
2f571334 | 4976 | |
5006671f RG |
4977 | /* Return true if the points-to solution *PT includes the variable |
4978 | declaration DECL. */ | |
15c15196 | 4979 | |
5006671f RG |
4980 | static bool |
4981 | pt_solution_includes_1 (struct pt_solution *pt, const_tree decl) | |
4982 | { | |
4983 | if (pt->anything) | |
4984 | return true; | |
2f571334 | 4985 | |
5006671f RG |
4986 | if (pt->nonlocal |
4987 | && is_global_var (decl)) | |
4988 | return true; | |
2f571334 | 4989 | |
5006671f RG |
4990 | if (pt->vars |
4991 | && bitmap_bit_p (pt->vars, DECL_UID (decl))) | |
4992 | return true; | |
2f571334 | 4993 | |
5006671f RG |
4994 | /* If the solution includes ESCAPED, check it. */ |
4995 | if (pt->escaped | |
4996 | && pt_solution_includes_1 (&cfun->gimple_df->escaped, decl)) | |
4997 | return true; | |
2f571334 | 4998 | |
5006671f | 4999 | return false; |
2f571334 | 5000 | } |
910fdc79 | 5001 | |
5006671f RG |
5002 | bool |
5003 | pt_solution_includes (struct pt_solution *pt, const_tree decl) | |
15c15196 | 5004 | { |
5006671f RG |
5005 | bool res = pt_solution_includes_1 (pt, decl); |
5006 | if (res) | |
5007 | ++pta_stats.pt_solution_includes_may_alias; | |
5008 | else | |
5009 | ++pta_stats.pt_solution_includes_no_alias; | |
5010 | return res; | |
5011 | } | |
15c15196 | 5012 | |
5006671f RG |
5013 | /* Return true if both points-to solutions PT1 and PT2 have a non-empty |
5014 | intersection. */ | |
15c15196 | 5015 | |
5006671f RG |
5016 | static bool |
5017 | pt_solutions_intersect_1 (struct pt_solution *pt1, struct pt_solution *pt2) | |
5018 | { | |
5019 | if (pt1->anything || pt2->anything) | |
5020 | return true; | |
15c15196 | 5021 | |
5006671f RG |
5022 | /* If either points to unknown global memory and the other points to |
5023 | any global memory they alias. */ | |
5024 | if ((pt1->nonlocal | |
5025 | && (pt2->nonlocal | |
5026 | || pt2->vars_contains_global)) | |
5027 | || (pt2->nonlocal | |
5028 | && pt1->vars_contains_global)) | |
5029 | return true; | |
15c15196 | 5030 | |
5006671f RG |
5031 | /* Check the escaped solution if required. */ |
5032 | if ((pt1->escaped || pt2->escaped) | |
5033 | && !pt_solution_empty_p (&cfun->gimple_df->escaped)) | |
5034 | { | |
5035 | /* If both point to escaped memory and that solution | |
5036 | is not empty they alias. */ | |
5037 | if (pt1->escaped && pt2->escaped) | |
5038 | return true; | |
15c15196 | 5039 | |
5006671f RG |
5040 | /* If either points to escaped memory see if the escaped solution |
5041 | intersects with the other. */ | |
5042 | if ((pt1->escaped | |
5043 | && pt_solutions_intersect_1 (&cfun->gimple_df->escaped, pt2)) | |
5044 | || (pt2->escaped | |
5045 | && pt_solutions_intersect_1 (&cfun->gimple_df->escaped, pt1))) | |
5046 | return true; | |
15c15196 RG |
5047 | } |
5048 | ||
5006671f RG |
5049 | /* Now both pointers alias if their points-to solution intersects. */ |
5050 | return (pt1->vars | |
5051 | && pt2->vars | |
5052 | && bitmap_intersect_p (pt1->vars, pt2->vars)); | |
5053 | } | |
5054 | ||
5055 | bool | |
5056 | pt_solutions_intersect (struct pt_solution *pt1, struct pt_solution *pt2) | |
5057 | { | |
5058 | bool res = pt_solutions_intersect_1 (pt1, pt2); | |
5059 | if (res) | |
5060 | ++pta_stats.pt_solutions_intersect_may_alias; | |
5061 | else | |
5062 | ++pta_stats.pt_solutions_intersect_no_alias; | |
5063 | return res; | |
15c15196 RG |
5064 | } |
5065 | ||
74d27244 RG |
5066 | /* Return true if both points-to solutions PT1 and PT2 for two restrict |
5067 | qualified pointers are possibly based on the same pointer. */ | |
5068 | ||
5069 | bool | |
5070 | pt_solutions_same_restrict_base (struct pt_solution *pt1, | |
5071 | struct pt_solution *pt2) | |
5072 | { | |
5073 | /* If we deal with points-to solutions of two restrict qualified | |
5074 | pointers solely rely on the pointed-to variable bitmap intersection. | |
5075 | For two pointers that are based on each other the bitmaps will | |
5076 | intersect. */ | |
5077 | if (pt1->vars_contains_restrict | |
5078 | && pt2->vars_contains_restrict) | |
5079 | { | |
5080 | gcc_assert (pt1->vars && pt2->vars); | |
5081 | return bitmap_intersect_p (pt1->vars, pt2->vars); | |
5082 | } | |
5083 | ||
5084 | return true; | |
5085 | } | |
5086 | ||
b7091901 | 5087 | |
63a4ef6f DN |
5088 | /* Dump points-to information to OUTFILE. */ |
5089 | ||
5006671f | 5090 | static void |
910fdc79 DB |
5091 | dump_sa_points_to_info (FILE *outfile) |
5092 | { | |
910fdc79 | 5093 | unsigned int i; |
63a4ef6f | 5094 | |
e8ca4159 | 5095 | fprintf (outfile, "\nPoints-to sets\n\n"); |
63a4ef6f | 5096 | |
910fdc79 DB |
5097 | if (dump_flags & TDF_STATS) |
5098 | { | |
5099 | fprintf (outfile, "Stats:\n"); | |
63a4ef6f | 5100 | fprintf (outfile, "Total vars: %d\n", stats.total_vars); |
3e5937d7 DB |
5101 | fprintf (outfile, "Non-pointer vars: %d\n", |
5102 | stats.nonpointer_vars); | |
63a4ef6f DN |
5103 | fprintf (outfile, "Statically unified vars: %d\n", |
5104 | stats.unified_vars_static); | |
63a4ef6f DN |
5105 | fprintf (outfile, "Dynamically unified vars: %d\n", |
5106 | stats.unified_vars_dynamic); | |
5107 | fprintf (outfile, "Iterations: %d\n", stats.iterations); | |
4ee00913 | 5108 | fprintf (outfile, "Number of edges: %d\n", stats.num_edges); |
3e5937d7 DB |
5109 | fprintf (outfile, "Number of implicit edges: %d\n", |
5110 | stats.num_implicit_edges); | |
910fdc79 | 5111 | } |
63a4ef6f | 5112 | |
910fdc79 DB |
5113 | for (i = 0; i < VEC_length (varinfo_t, varmap); i++) |
5114 | dump_solution_for_var (outfile, i); | |
5115 | } | |
5116 | ||
5117 | ||
63a4ef6f DN |
5118 | /* Debug points-to information to stderr. */ |
5119 | ||
5120 | void | |
5121 | debug_sa_points_to_info (void) | |
5122 | { | |
5123 | dump_sa_points_to_info (stderr); | |
5124 | } | |
5125 | ||
5126 | ||
910fdc79 DB |
5127 | /* Initialize the always-existing constraint variables for NULL |
5128 | ANYTHING, READONLY, and INTEGER */ | |
5129 | ||
5130 | static void | |
5131 | init_base_vars (void) | |
5132 | { | |
5133 | struct constraint_expr lhs, rhs; | |
0bbf2ffa RG |
5134 | varinfo_t var_anything; |
5135 | varinfo_t var_nothing; | |
5136 | varinfo_t var_readonly; | |
5137 | varinfo_t var_escaped; | |
5138 | varinfo_t var_nonlocal; | |
5139 | varinfo_t var_callused; | |
5140 | varinfo_t var_storedanything; | |
5141 | varinfo_t var_integer; | |
910fdc79 DB |
5142 | |
5143 | /* Create the NULL variable, used to represent that a variable points | |
5144 | to NULL. */ | |
0bbf2ffa RG |
5145 | var_nothing = new_var_info (NULL_TREE, "NULL"); |
5146 | gcc_assert (var_nothing->id == nothing_id); | |
910fdc79 DB |
5147 | var_nothing->is_artificial_var = 1; |
5148 | var_nothing->offset = 0; | |
5149 | var_nothing->size = ~0; | |
5150 | var_nothing->fullsize = ~0; | |
13c2c08b | 5151 | var_nothing->is_special_var = 1; |
910fdc79 DB |
5152 | |
5153 | /* Create the ANYTHING variable, used to represent that a variable | |
5154 | points to some unknown piece of memory. */ | |
0bbf2ffa RG |
5155 | var_anything = new_var_info (NULL_TREE, "ANYTHING"); |
5156 | gcc_assert (var_anything->id == anything_id); | |
910fdc79 DB |
5157 | var_anything->is_artificial_var = 1; |
5158 | var_anything->size = ~0; | |
5159 | var_anything->offset = 0; | |
5160 | var_anything->next = NULL; | |
5161 | var_anything->fullsize = ~0; | |
13c2c08b | 5162 | var_anything->is_special_var = 1; |
910fdc79 DB |
5163 | |
5164 | /* Anything points to anything. This makes deref constraints just | |
c58936b6 | 5165 | work in the presence of linked list and other p = *p type loops, |
910fdc79 | 5166 | by saying that *ANYTHING = ANYTHING. */ |
910fdc79 DB |
5167 | lhs.type = SCALAR; |
5168 | lhs.var = anything_id; | |
5169 | lhs.offset = 0; | |
3e5937d7 | 5170 | rhs.type = ADDRESSOF; |
910fdc79 DB |
5171 | rhs.var = anything_id; |
5172 | rhs.offset = 0; | |
e8ca4159 | 5173 | |
a5eadacc DB |
5174 | /* This specifically does not use process_constraint because |
5175 | process_constraint ignores all anything = anything constraints, since all | |
5176 | but this one are redundant. */ | |
b5efa470 | 5177 | VEC_safe_push (constraint_t, heap, constraints, new_constraint (lhs, rhs)); |
c58936b6 | 5178 | |
910fdc79 DB |
5179 | /* Create the READONLY variable, used to represent that a variable |
5180 | points to readonly memory. */ | |
0bbf2ffa RG |
5181 | var_readonly = new_var_info (NULL_TREE, "READONLY"); |
5182 | gcc_assert (var_readonly->id == readonly_id); | |
910fdc79 DB |
5183 | var_readonly->is_artificial_var = 1; |
5184 | var_readonly->offset = 0; | |
5185 | var_readonly->size = ~0; | |
5186 | var_readonly->fullsize = ~0; | |
5187 | var_readonly->next = NULL; | |
13c2c08b | 5188 | var_readonly->is_special_var = 1; |
910fdc79 DB |
5189 | |
5190 | /* readonly memory points to anything, in order to make deref | |
5191 | easier. In reality, it points to anything the particular | |
5192 | readonly variable can point to, but we don't track this | |
607fb860 | 5193 | separately. */ |
910fdc79 DB |
5194 | lhs.type = SCALAR; |
5195 | lhs.var = readonly_id; | |
5196 | lhs.offset = 0; | |
3e5937d7 | 5197 | rhs.type = ADDRESSOF; |
b7091901 | 5198 | rhs.var = readonly_id; /* FIXME */ |
910fdc79 | 5199 | rhs.offset = 0; |
b7091901 | 5200 | process_constraint (new_constraint (lhs, rhs)); |
c58936b6 | 5201 | |
b7091901 RG |
5202 | /* Create the ESCAPED variable, used to represent the set of escaped |
5203 | memory. */ | |
0bbf2ffa RG |
5204 | var_escaped = new_var_info (NULL_TREE, "ESCAPED"); |
5205 | gcc_assert (var_escaped->id == escaped_id); | |
b7091901 RG |
5206 | var_escaped->is_artificial_var = 1; |
5207 | var_escaped->offset = 0; | |
5208 | var_escaped->size = ~0; | |
5209 | var_escaped->fullsize = ~0; | |
5210 | var_escaped->is_special_var = 0; | |
b7091901 | 5211 | |
b7091901 RG |
5212 | /* Create the NONLOCAL variable, used to represent the set of nonlocal |
5213 | memory. */ | |
0bbf2ffa RG |
5214 | var_nonlocal = new_var_info (NULL_TREE, "NONLOCAL"); |
5215 | gcc_assert (var_nonlocal->id == nonlocal_id); | |
b7091901 RG |
5216 | var_nonlocal->is_artificial_var = 1; |
5217 | var_nonlocal->offset = 0; | |
5218 | var_nonlocal->size = ~0; | |
5219 | var_nonlocal->fullsize = ~0; | |
5220 | var_nonlocal->is_special_var = 1; | |
b7091901 | 5221 | |
5006671f RG |
5222 | /* ESCAPED = *ESCAPED, because escaped is may-deref'd at calls, etc. */ |
5223 | lhs.type = SCALAR; | |
5224 | lhs.var = escaped_id; | |
5225 | lhs.offset = 0; | |
5226 | rhs.type = DEREF; | |
5227 | rhs.var = escaped_id; | |
5228 | rhs.offset = 0; | |
5229 | process_constraint (new_constraint (lhs, rhs)); | |
5230 | ||
5231 | /* ESCAPED = ESCAPED + UNKNOWN_OFFSET, because if a sub-field escapes the | |
5232 | whole variable escapes. */ | |
5233 | lhs.type = SCALAR; | |
5234 | lhs.var = escaped_id; | |
5235 | lhs.offset = 0; | |
5236 | rhs.type = SCALAR; | |
5237 | rhs.var = escaped_id; | |
5238 | rhs.offset = UNKNOWN_OFFSET; | |
5239 | process_constraint (new_constraint (lhs, rhs)); | |
5240 | ||
5241 | /* *ESCAPED = NONLOCAL. This is true because we have to assume | |
5242 | everything pointed to by escaped points to what global memory can | |
5243 | point to. */ | |
5244 | lhs.type = DEREF; | |
5245 | lhs.var = escaped_id; | |
5246 | lhs.offset = 0; | |
5247 | rhs.type = SCALAR; | |
5248 | rhs.var = nonlocal_id; | |
5249 | rhs.offset = 0; | |
5250 | process_constraint (new_constraint (lhs, rhs)); | |
5251 | ||
5252 | /* NONLOCAL = &NONLOCAL, NONLOCAL = &ESCAPED. This is true because | |
5253 | global memory may point to global memory and escaped memory. */ | |
b7091901 RG |
5254 | lhs.type = SCALAR; |
5255 | lhs.var = nonlocal_id; | |
5256 | lhs.offset = 0; | |
5257 | rhs.type = ADDRESSOF; | |
5006671f RG |
5258 | rhs.var = nonlocal_id; |
5259 | rhs.offset = 0; | |
5260 | process_constraint (new_constraint (lhs, rhs)); | |
5261 | rhs.type = ADDRESSOF; | |
b7091901 RG |
5262 | rhs.var = escaped_id; |
5263 | rhs.offset = 0; | |
910fdc79 | 5264 | process_constraint (new_constraint (lhs, rhs)); |
c58936b6 | 5265 | |
15c15196 RG |
5266 | /* Create the CALLUSED variable, used to represent the set of call-used |
5267 | memory. */ | |
0bbf2ffa RG |
5268 | var_callused = new_var_info (NULL_TREE, "CALLUSED"); |
5269 | gcc_assert (var_callused->id == callused_id); | |
15c15196 RG |
5270 | var_callused->is_artificial_var = 1; |
5271 | var_callused->offset = 0; | |
5272 | var_callused->size = ~0; | |
5273 | var_callused->fullsize = ~0; | |
5274 | var_callused->is_special_var = 0; | |
15c15196 RG |
5275 | |
5276 | /* CALLUSED = *CALLUSED, because call-used is may-deref'd at calls, etc. */ | |
5277 | lhs.type = SCALAR; | |
5278 | lhs.var = callused_id; | |
5279 | lhs.offset = 0; | |
5280 | rhs.type = DEREF; | |
5281 | rhs.var = callused_id; | |
5282 | rhs.offset = 0; | |
faf2ecc5 | 5283 | process_constraint (new_constraint (lhs, rhs)); |
15c15196 | 5284 | |
5006671f RG |
5285 | /* CALLUSED = CALLUSED + UNKNOWN, because if a sub-field is call-used the |
5286 | whole variable is call-used. */ | |
5287 | lhs.type = SCALAR; | |
5288 | lhs.var = callused_id; | |
5289 | lhs.offset = 0; | |
5290 | rhs.type = SCALAR; | |
5291 | rhs.var = callused_id; | |
5292 | rhs.offset = UNKNOWN_OFFSET; | |
5293 | process_constraint (new_constraint (lhs, rhs)); | |
5294 | ||
9e39dba6 RG |
5295 | /* Create the STOREDANYTHING variable, used to represent the set of |
5296 | variables stored to *ANYTHING. */ | |
0bbf2ffa RG |
5297 | var_storedanything = new_var_info (NULL_TREE, "STOREDANYTHING"); |
5298 | gcc_assert (var_storedanything->id == storedanything_id); | |
9e39dba6 RG |
5299 | var_storedanything->is_artificial_var = 1; |
5300 | var_storedanything->offset = 0; | |
5301 | var_storedanything->size = ~0; | |
5302 | var_storedanything->fullsize = ~0; | |
5303 | var_storedanything->is_special_var = 0; | |
9e39dba6 | 5304 | |
910fdc79 | 5305 | /* Create the INTEGER variable, used to represent that a variable points |
5006671f | 5306 | to what an INTEGER "points to". */ |
0bbf2ffa RG |
5307 | var_integer = new_var_info (NULL_TREE, "INTEGER"); |
5308 | gcc_assert (var_integer->id == integer_id); | |
910fdc79 DB |
5309 | var_integer->is_artificial_var = 1; |
5310 | var_integer->size = ~0; | |
5311 | var_integer->fullsize = ~0; | |
5312 | var_integer->offset = 0; | |
5313 | var_integer->next = NULL; | |
13c2c08b | 5314 | var_integer->is_special_var = 1; |
a5eadacc | 5315 | |
21392f19 DB |
5316 | /* INTEGER = ANYTHING, because we don't know where a dereference of |
5317 | a random integer will point to. */ | |
a5eadacc DB |
5318 | lhs.type = SCALAR; |
5319 | lhs.var = integer_id; | |
5320 | lhs.offset = 0; | |
3e5937d7 | 5321 | rhs.type = ADDRESSOF; |
a5eadacc DB |
5322 | rhs.var = anything_id; |
5323 | rhs.offset = 0; | |
5324 | process_constraint (new_constraint (lhs, rhs)); | |
c58936b6 | 5325 | } |
910fdc79 | 5326 | |
4ee00913 | 5327 | /* Initialize things necessary to perform PTA */ |
910fdc79 | 5328 | |
4ee00913 DB |
5329 | static void |
5330 | init_alias_vars (void) | |
910fdc79 | 5331 | { |
e5bae89b RG |
5332 | use_field_sensitive = (MAX_FIELDS_FOR_FIELD_SENSITIVE > 1); |
5333 | ||
3e5937d7 DB |
5334 | bitmap_obstack_initialize (&pta_obstack); |
5335 | bitmap_obstack_initialize (&oldpta_obstack); | |
4ee00913 | 5336 | bitmap_obstack_initialize (&predbitmap_obstack); |
910fdc79 | 5337 | |
c58936b6 | 5338 | constraint_pool = create_alloc_pool ("Constraint pool", |
910fdc79 DB |
5339 | sizeof (struct constraint), 30); |
5340 | variable_info_pool = create_alloc_pool ("Variable info pool", | |
5341 | sizeof (struct variable_info), 30); | |
b5efa470 DB |
5342 | constraints = VEC_alloc (constraint_t, heap, 8); |
5343 | varmap = VEC_alloc (varinfo_t, heap, 8); | |
15814ba0 | 5344 | vi_for_tree = pointer_map_create (); |
3e5937d7 | 5345 | |
910fdc79 | 5346 | memset (&stats, 0, sizeof (stats)); |
1296c31f DB |
5347 | shared_bitmap_table = htab_create (511, shared_bitmap_hash, |
5348 | shared_bitmap_eq, free); | |
910fdc79 | 5349 | init_base_vars (); |
4ee00913 DB |
5350 | } |
5351 | ||
3e5937d7 DB |
5352 | /* Remove the REF and ADDRESS edges from GRAPH, as well as all the |
5353 | predecessor edges. */ | |
5354 | ||
5355 | static void | |
5356 | remove_preds_and_fake_succs (constraint_graph_t graph) | |
5357 | { | |
5358 | unsigned int i; | |
5359 | ||
5360 | /* Clear the implicit ref and address nodes from the successor | |
5361 | lists. */ | |
5362 | for (i = 0; i < FIRST_REF_NODE; i++) | |
5363 | { | |
5364 | if (graph->succs[i]) | |
5365 | bitmap_clear_range (graph->succs[i], FIRST_REF_NODE, | |
5366 | FIRST_REF_NODE * 2); | |
5367 | } | |
5368 | ||
5369 | /* Free the successor list for the non-ref nodes. */ | |
5370 | for (i = FIRST_REF_NODE; i < graph->size; i++) | |
5371 | { | |
5372 | if (graph->succs[i]) | |
5373 | BITMAP_FREE (graph->succs[i]); | |
5374 | } | |
5375 | ||
5376 | /* Now reallocate the size of the successor list as, and blow away | |
5377 | the predecessor bitmaps. */ | |
5378 | graph->size = VEC_length (varinfo_t, varmap); | |
c22940cd | 5379 | graph->succs = XRESIZEVEC (bitmap, graph->succs, graph->size); |
3e5937d7 DB |
5380 | |
5381 | free (graph->implicit_preds); | |
5382 | graph->implicit_preds = NULL; | |
5383 | free (graph->preds); | |
5384 | graph->preds = NULL; | |
5385 | bitmap_obstack_release (&predbitmap_obstack); | |
5386 | } | |
5387 | ||
5006671f RG |
5388 | /* Initialize the heapvar for statement mapping. */ |
5389 | ||
5390 | static void | |
5391 | init_alias_heapvars (void) | |
5392 | { | |
5393 | if (!heapvar_for_stmt) | |
8bc88f25 | 5394 | heapvar_for_stmt = htab_create_ggc (11, tree_map_hash, heapvar_map_eq, |
5006671f RG |
5395 | NULL); |
5396 | } | |
5397 | ||
5398 | /* Delete the heapvar for statement mapping. */ | |
5399 | ||
5400 | void | |
5401 | delete_alias_heapvars (void) | |
5402 | { | |
5403 | if (heapvar_for_stmt) | |
5404 | htab_delete (heapvar_for_stmt); | |
5405 | heapvar_for_stmt = NULL; | |
5406 | } | |
5407 | ||
5c245b95 | 5408 | /* Solve the constraint set. */ |
4ee00913 | 5409 | |
5006671f | 5410 | static void |
5c245b95 | 5411 | solve_constraints (void) |
4ee00913 | 5412 | { |
3e5937d7 | 5413 | struct scc_info *si; |
910fdc79 | 5414 | |
910fdc79 DB |
5415 | if (dump_file) |
5416 | { | |
e8ca4159 | 5417 | fprintf (dump_file, "Points-to analysis\n\nConstraints:\n\n"); |
910fdc79 DB |
5418 | dump_constraints (dump_file); |
5419 | } | |
c58936b6 | 5420 | |
21392f19 DB |
5421 | if (dump_file) |
5422 | fprintf (dump_file, | |
5423 | "\nCollapsing static cycles and doing variable " | |
7b765bed DB |
5424 | "substitution\n"); |
5425 | ||
5426 | init_graph (VEC_length (varinfo_t, varmap) * 2); | |
b8698a0f | 5427 | |
7b765bed DB |
5428 | if (dump_file) |
5429 | fprintf (dump_file, "Building predecessor graph\n"); | |
3e5937d7 | 5430 | build_pred_graph (); |
b8698a0f | 5431 | |
7b765bed DB |
5432 | if (dump_file) |
5433 | fprintf (dump_file, "Detecting pointer and location " | |
5434 | "equivalences\n"); | |
3e5937d7 | 5435 | si = perform_var_substitution (graph); |
b8698a0f | 5436 | |
7b765bed DB |
5437 | if (dump_file) |
5438 | fprintf (dump_file, "Rewriting constraints and unifying " | |
5439 | "variables\n"); | |
5440 | rewrite_constraints (graph, si); | |
3e5937d7 DB |
5441 | |
5442 | build_succ_graph (); | |
9e39dba6 | 5443 | free_var_substitution_info (si); |
fc93bcb6 FP |
5444 | |
5445 | if (dump_file && (dump_flags & TDF_GRAPH)) | |
5446 | dump_constraint_graph (dump_file); | |
5447 | ||
7b765bed DB |
5448 | move_complex_constraints (graph); |
5449 | ||
5450 | if (dump_file) | |
5451 | fprintf (dump_file, "Uniting pointer but not location equivalent " | |
5452 | "variables\n"); | |
5453 | unite_pointer_equivalences (graph); | |
5454 | ||
5455 | if (dump_file) | |
5456 | fprintf (dump_file, "Finding indirect cycles\n"); | |
3e5937d7 | 5457 | find_indirect_cycles (graph); |
c58936b6 | 5458 | |
3e5937d7 DB |
5459 | /* Implicit nodes and predecessors are no longer necessary at this |
5460 | point. */ | |
5461 | remove_preds_and_fake_succs (graph); | |
c58936b6 | 5462 | |
21392f19 | 5463 | if (dump_file) |
7b765bed | 5464 | fprintf (dump_file, "Solving graph\n"); |
c58936b6 | 5465 | |
21392f19 | 5466 | solve_graph (graph); |
c58936b6 | 5467 | |
910fdc79 DB |
5468 | if (dump_file) |
5469 | dump_sa_points_to_info (dump_file); | |
5c245b95 RG |
5470 | } |
5471 | ||
5472 | /* Create points-to sets for the current function. See the comments | |
5473 | at the start of the file for an algorithmic overview. */ | |
5474 | ||
5475 | static void | |
5476 | compute_points_to_sets (void) | |
5477 | { | |
5478 | basic_block bb; | |
5479 | unsigned i; | |
5480 | varinfo_t vi; | |
5481 | ||
5482 | timevar_push (TV_TREE_PTA); | |
5483 | ||
5484 | init_alias_vars (); | |
5485 | init_alias_heapvars (); | |
5486 | ||
5487 | intra_create_variable_infos (); | |
5488 | ||
5489 | /* Now walk all statements and derive aliases. */ | |
5490 | FOR_EACH_BB (bb) | |
5491 | { | |
5492 | gimple_stmt_iterator gsi; | |
5493 | ||
5494 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
5495 | { | |
5496 | gimple phi = gsi_stmt (gsi); | |
5497 | ||
5498 | if (is_gimple_reg (gimple_phi_result (phi))) | |
5499 | find_func_aliases (phi); | |
5500 | } | |
5501 | ||
5502 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
5503 | { | |
5504 | gimple stmt = gsi_stmt (gsi); | |
5505 | ||
5506 | find_func_aliases (stmt); | |
5507 | } | |
5508 | } | |
5509 | ||
5510 | /* From the constraints compute the points-to sets. */ | |
5511 | solve_constraints (); | |
c58936b6 | 5512 | |
5006671f RG |
5513 | /* Compute the points-to sets for ESCAPED and CALLUSED used for |
5514 | call-clobber analysis. */ | |
0bbf2ffa RG |
5515 | find_what_var_points_to (get_varinfo (escaped_id), |
5516 | &cfun->gimple_df->escaped); | |
5517 | find_what_var_points_to (get_varinfo (callused_id), | |
5518 | &cfun->gimple_df->callused); | |
5006671f RG |
5519 | |
5520 | /* Make sure the ESCAPED solution (which is used as placeholder in | |
5521 | other solutions) does not reference itself. This simplifies | |
5522 | points-to solution queries. */ | |
5523 | cfun->gimple_df->escaped.escaped = 0; | |
5524 | ||
14c41b9b RG |
5525 | /* Mark escaped HEAP variables as global. */ |
5526 | for (i = 0; VEC_iterate (varinfo_t, varmap, i, vi); ++i) | |
5527 | if (vi->is_heap_var | |
91deb937 | 5528 | && !vi->is_restrict_var |
14c41b9b | 5529 | && !vi->is_global_var) |
91deb937 RG |
5530 | DECL_EXTERNAL (vi->decl) = vi->is_global_var |
5531 | = pt_solution_includes (&cfun->gimple_df->escaped, vi->decl); | |
14c41b9b | 5532 | |
5006671f RG |
5533 | /* Compute the points-to sets for pointer SSA_NAMEs. */ |
5534 | for (i = 0; i < num_ssa_names; ++i) | |
5535 | { | |
5536 | tree ptr = ssa_name (i); | |
5537 | if (ptr | |
5538 | && POINTER_TYPE_P (TREE_TYPE (ptr))) | |
4d7a65ea | 5539 | find_what_p_points_to (ptr); |
5006671f | 5540 | } |
e8ca4159 DN |
5541 | |
5542 | timevar_pop (TV_TREE_PTA); | |
910fdc79 DB |
5543 | } |
5544 | ||
910fdc79 DB |
5545 | |
5546 | /* Delete created points-to sets. */ | |
5547 | ||
5006671f | 5548 | static void |
e8ca4159 | 5549 | delete_points_to_sets (void) |
910fdc79 | 5550 | { |
7b765bed | 5551 | unsigned int i; |
c58936b6 | 5552 | |
1296c31f | 5553 | htab_delete (shared_bitmap_table); |
3e5937d7 DB |
5554 | if (dump_file && (dump_flags & TDF_STATS)) |
5555 | fprintf (dump_file, "Points to sets created:%d\n", | |
5556 | stats.points_to_sets_created); | |
5557 | ||
15814ba0 | 5558 | pointer_map_destroy (vi_for_tree); |
3e5937d7 | 5559 | bitmap_obstack_release (&pta_obstack); |
b5efa470 | 5560 | VEC_free (constraint_t, heap, constraints); |
c58936b6 | 5561 | |
7b765bed | 5562 | for (i = 0; i < graph->size; i++) |
3e5937d7 | 5563 | VEC_free (constraint_t, heap, graph->complex[i]); |
285463b5 | 5564 | free (graph->complex); |
21392f19 | 5565 | |
3e5937d7 | 5566 | free (graph->rep); |
57250223 | 5567 | free (graph->succs); |
7b765bed DB |
5568 | free (graph->pe); |
5569 | free (graph->pe_rep); | |
3e5937d7 | 5570 | free (graph->indirect_cycles); |
b5efa470 DB |
5571 | free (graph); |
5572 | ||
5573 | VEC_free (varinfo_t, heap, varmap); | |
910fdc79 | 5574 | free_alloc_pool (variable_info_pool); |
c58936b6 | 5575 | free_alloc_pool (constraint_pool); |
910fdc79 | 5576 | } |
973162ec | 5577 | |
5006671f RG |
5578 | |
5579 | /* Compute points-to information for every SSA_NAME pointer in the | |
5580 | current function and compute the transitive closure of escaped | |
5581 | variables to re-initialize the call-clobber states of local variables. */ | |
5582 | ||
5583 | unsigned int | |
5584 | compute_may_aliases (void) | |
5585 | { | |
5586 | /* For each pointer P_i, determine the sets of variables that P_i may | |
5587 | point-to. Compute the reachability set of escaped and call-used | |
5588 | variables. */ | |
5589 | compute_points_to_sets (); | |
5590 | ||
5591 | /* Debugging dumps. */ | |
5592 | if (dump_file) | |
5593 | { | |
5594 | dump_alias_info (dump_file); | |
5595 | ||
5596 | if (dump_flags & TDF_DETAILS) | |
5597 | dump_referenced_vars (dump_file); | |
5598 | } | |
5599 | ||
5600 | /* Deallocate memory used by aliasing data structures and the internal | |
5601 | points-to solution. */ | |
5602 | delete_points_to_sets (); | |
5603 | ||
5604 | gcc_assert (!need_ssa_update_p (cfun)); | |
5605 | ||
5606 | return 0; | |
5607 | } | |
5608 | ||
248fc9f3 RG |
5609 | static bool |
5610 | gate_tree_pta (void) | |
5611 | { | |
5612 | return flag_tree_pta; | |
5613 | } | |
5006671f RG |
5614 | |
5615 | /* A dummy pass to cause points-to information to be computed via | |
5616 | TODO_rebuild_alias. */ | |
5617 | ||
5618 | struct gimple_opt_pass pass_build_alias = | |
5619 | { | |
5620 | { | |
5621 | GIMPLE_PASS, | |
5622 | "alias", /* name */ | |
248fc9f3 | 5623 | gate_tree_pta, /* gate */ |
5006671f RG |
5624 | NULL, /* execute */ |
5625 | NULL, /* sub */ | |
5626 | NULL, /* next */ | |
5627 | 0, /* static_pass_number */ | |
7072a650 | 5628 | TV_NONE, /* tv_id */ |
5006671f | 5629 | PROP_cfg | PROP_ssa, /* properties_required */ |
4effdf02 | 5630 | 0, /* properties_provided */ |
5006671f RG |
5631 | 0, /* properties_destroyed */ |
5632 | 0, /* todo_flags_start */ | |
5633 | TODO_rebuild_alias | TODO_dump_func /* todo_flags_finish */ | |
5634 | } | |
5635 | }; | |
5636 | ||
6b8ed145 RG |
5637 | /* A dummy pass to cause points-to information to be computed via |
5638 | TODO_rebuild_alias. */ | |
5639 | ||
5640 | struct gimple_opt_pass pass_build_ealias = | |
5641 | { | |
5642 | { | |
5643 | GIMPLE_PASS, | |
5644 | "ealias", /* name */ | |
5645 | gate_tree_pta, /* gate */ | |
5646 | NULL, /* execute */ | |
5647 | NULL, /* sub */ | |
5648 | NULL, /* next */ | |
5649 | 0, /* static_pass_number */ | |
5650 | TV_NONE, /* tv_id */ | |
5651 | PROP_cfg | PROP_ssa, /* properties_required */ | |
5652 | 0, /* properties_provided */ | |
5653 | 0, /* properties_destroyed */ | |
5654 | 0, /* todo_flags_start */ | |
5655 | TODO_rebuild_alias | TODO_dump_func /* todo_flags_finish */ | |
5656 | } | |
5657 | }; | |
5658 | ||
5006671f | 5659 | |
4ee00913 DB |
5660 | /* Return true if we should execute IPA PTA. */ |
5661 | static bool | |
5662 | gate_ipa_pta (void) | |
5663 | { | |
de925a03 RG |
5664 | return (optimize |
5665 | && flag_ipa_pta | |
4ee00913 DB |
5666 | /* Don't bother doing anything if the program has errors. */ |
5667 | && !(errorcount || sorrycount)); | |
5668 | } | |
5669 | ||
5670 | /* Execute the driver for IPA PTA. */ | |
c2924966 | 5671 | static unsigned int |
4ee00913 DB |
5672 | ipa_pta_execute (void) |
5673 | { | |
5674 | struct cgraph_node *node; | |
3e5937d7 | 5675 | |
4ee00913 | 5676 | in_ipa_mode = 1; |
5c245b95 | 5677 | |
4cf4d6a3 | 5678 | init_alias_heapvars (); |
4ee00913 | 5679 | init_alias_vars (); |
c58936b6 | 5680 | |
5c245b95 | 5681 | /* Build the constraints. */ |
4ee00913 DB |
5682 | for (node = cgraph_nodes; node; node = node->next) |
5683 | { | |
1de812a6 | 5684 | unsigned int varid; |
c58936b6 | 5685 | |
5c245b95 RG |
5686 | /* Nodes without a body are not interesting. Especially do not |
5687 | visit clones at this point for now - we get duplicate decls | |
5688 | there for inline clones at least. */ | |
5689 | if (!gimple_has_body_p (node->decl) | |
5690 | || node->clone_of) | |
5691 | continue; | |
5692 | ||
5693 | /* It does not make sense to have graph edges into or out of | |
5694 | externally visible functions. There is no extra information | |
5695 | we can gather from them. */ | |
5696 | if (node->local.externally_visible) | |
5697 | continue; | |
5698 | ||
1de812a6 JH |
5699 | varid = create_function_info_for (node->decl, |
5700 | cgraph_node_name (node)); | |
4ee00913 | 5701 | } |
5c245b95 | 5702 | |
4ee00913 DB |
5703 | for (node = cgraph_nodes; node; node = node->next) |
5704 | { | |
5c245b95 RG |
5705 | struct function *func; |
5706 | basic_block bb; | |
5707 | tree old_func_decl; | |
4ee00913 | 5708 | |
5c245b95 RG |
5709 | /* Nodes without a body are not interesting. */ |
5710 | if (!gimple_has_body_p (node->decl) | |
5711 | || node->clone_of) | |
5712 | continue; | |
c58936b6 | 5713 | |
5c245b95 RG |
5714 | if (dump_file) |
5715 | fprintf (dump_file, | |
5716 | "Generating constraints for %s\n", | |
5717 | cgraph_node_name (node)); | |
c58936b6 | 5718 | |
5c245b95 RG |
5719 | func = DECL_STRUCT_FUNCTION (node->decl); |
5720 | old_func_decl = current_function_decl; | |
5721 | push_cfun (func); | |
5722 | current_function_decl = node->decl; | |
726a989a | 5723 | |
5c245b95 RG |
5724 | /* For externally visible functions use local constraints for |
5725 | their arguments. For local functions we see all callers | |
5726 | and thus do not need initial constraints for parameters. */ | |
5727 | if (node->local.externally_visible) | |
5728 | intra_create_variable_infos (); | |
4ee00913 | 5729 | |
5c245b95 RG |
5730 | /* Build constriants for the function body. */ |
5731 | FOR_EACH_BB_FN (bb, func) | |
5732 | { | |
5733 | gimple_stmt_iterator gsi; | |
c58936b6 | 5734 | |
5c245b95 RG |
5735 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); |
5736 | gsi_next (&gsi)) | |
5737 | { | |
5738 | gimple phi = gsi_stmt (gsi); | |
c58936b6 | 5739 | |
5c245b95 RG |
5740 | if (is_gimple_reg (gimple_phi_result (phi))) |
5741 | find_func_aliases (phi); | |
5742 | } | |
3e5937d7 | 5743 | |
5c245b95 RG |
5744 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
5745 | { | |
5746 | gimple stmt = gsi_stmt (gsi); | |
3e5937d7 | 5747 | |
5c245b95 RG |
5748 | find_func_aliases (stmt); |
5749 | } | |
5750 | } | |
c58936b6 | 5751 | |
5c245b95 RG |
5752 | current_function_decl = old_func_decl; |
5753 | pop_cfun (); | |
5754 | } | |
c58936b6 | 5755 | |
5c245b95 RG |
5756 | /* From the constraints compute the points-to sets. */ |
5757 | solve_constraints (); | |
c58936b6 | 5758 | |
5c245b95 | 5759 | delete_points_to_sets (); |
c58936b6 | 5760 | |
4ee00913 | 5761 | in_ipa_mode = 0; |
5c245b95 | 5762 | |
c2924966 | 5763 | return 0; |
4ee00913 | 5764 | } |
c58936b6 | 5765 | |
8ddbbcae | 5766 | struct simple_ipa_opt_pass pass_ipa_pta = |
4ee00913 | 5767 | { |
8ddbbcae JH |
5768 | { |
5769 | SIMPLE_IPA_PASS, | |
4ee00913 DB |
5770 | "pta", /* name */ |
5771 | gate_ipa_pta, /* gate */ | |
5772 | ipa_pta_execute, /* execute */ | |
5773 | NULL, /* sub */ | |
5774 | NULL, /* next */ | |
5775 | 0, /* static_pass_number */ | |
5776 | TV_IPA_PTA, /* tv_id */ | |
5777 | 0, /* properties_required */ | |
5778 | 0, /* properties_provided */ | |
5779 | 0, /* properties_destroyed */ | |
5780 | 0, /* todo_flags_start */ | |
8ddbbcae JH |
5781 | TODO_update_ssa /* todo_flags_finish */ |
5782 | } | |
4ee00913 DB |
5783 | }; |
5784 | ||
c900f6aa | 5785 | |
c900f6aa | 5786 | #include "gt-tree-ssa-structalias.h" |