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808f4dfe 1/* Classes for modeling the state of memory.
7adcbafe 2 Copyright (C) 2020-2022 Free Software Foundation, Inc.
808f4dfe
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3 Contributed by David Malcolm <dmalcolm@redhat.com>.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it
8under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 3, or (at your option)
10any later version.
11
12GCC is distributed in the hope that it will be useful, but
13WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING3. If not see
19<http://www.gnu.org/licenses/>. */
20
21#ifndef GCC_ANALYZER_STORE_H
22#define GCC_ANALYZER_STORE_H
23
24/* Implementation of the region-based ternary model described in:
25 "A Memory Model for Static Analysis of C Programs"
26 (Zhongxing Xu, Ted Kremenek, and Jian Zhang)
27 http://lcs.ios.ac.cn/~xuzb/canalyze/memmodel.pdf */
28
29/* The store models memory as a collection of "clusters", where regions
30 are partitioned into clusters via their base region.
31
32 For example, given:
33 int a, b, c;
34 struct coord { double x; double y; } verts[3];
35 then "verts[0].y" and "verts[1].x" both have "verts" as their base region.
36 Each of a, b, c, and verts will have their own clusters, so that we
37 know that writes to e.g. "verts[1].x".don't affect e.g. "a".
38
39 Within each cluster we store a map of bindings to values, where the
40 binding keys can be either concrete or symbolic.
41
42 Concrete bindings affect a specific range of bits relative to the start
43 of the base region of the cluster, whereas symbolic bindings affect
44 a specific subregion within the cluster.
45
46 Consider (from the symbolic-1.c testcase):
47
48 char arr[1024];
49 arr[2] = a; (1)
50 arr[3] = b; (2)
51 After (1) and (2), the cluster for "arr" has concrete bindings
52 for bits 16-23 and for bits 24-31, with svalues "INIT_VAL(a)"
53 and "INIT_VAL(b)" respectively:
54 cluster: {bits 16-23: "INIT_VAL(a)",
55 bits 24-31: "INIT_VAL(b)";
56 flags: {}}
57 Attempting to query unbound subregions e.g. arr[4] will
58 return "UNINITIALIZED".
59 "a" and "b" are each in their own clusters, with no explicit
60 bindings, and thus implicitly have value INIT_VAL(a) and INIT_VAL(b).
61
62 arr[3] = c; (3)
63 After (3), the concrete binding for bits 24-31 is replaced with the
64 svalue "INIT_VAL(c)":
65 cluster: {bits 16-23: "INIT_VAL(a)", (from before)
66 bits 24-31: "INIT_VAL(c)"; (updated)
67 flags: {}}
68
69 arr[i] = d; (4)
70 After (4), we lose the concrete bindings and replace them with a
71 symbolic binding for "arr[i]", with svalue "INIT_VAL(d)". We also
72 mark the cluster as having been "symbolically touched": future
73 attempts to query the values of subregions other than "arr[i]",
74 such as "arr[3]" are "UNKNOWN", since we don't know if the write
75 to arr[i] affected them.
76 cluster: {symbolic_key(arr[i]): "INIT_VAL(d)";
77 flags: {TOUCHED}}
78
79 arr[j] = e; (5)
80 After (5), we lose the symbolic binding for "arr[i]" since we could
81 have overwritten it, and add a symbolic binding for "arr[j]".
82 cluster: {symbolic_key(arr[j]): "INIT_VAL(d)"; (different symbolic
83 flags: {TOUCHED}} binding)
84
85 arr[3] = f; (6)
86 After (6), we lose the symbolic binding for "arr[j]" since we could
87 have overwritten it, and gain a concrete binding for bits 24-31
88 again, this time with svalue "INIT_VAL(e)":
89 cluster: {bits 24-31: "INIT_VAL(d)";
90 flags: {TOUCHED}}
91 The cluster is still flagged as touched, so that we know that
92 accesses to other elements are "UNKNOWN" rather than
93 "UNINITIALIZED".
94
95 Handling symbolic regions requires us to handle aliasing.
96
97 In the first example above, each of a, b, c and verts are non-symbolic
98 base regions and so their clusters are "concrete clusters", whereas given:
99 struct coord *p, *q;
100 then "*p" and "*q" are symbolic base regions, and thus "*p" and "*q"
101 have "symbolic clusters".
102
103 In the above, "verts[i].x" will have a symbolic *binding* within a
104 concrete cluster for "verts", whereas "*p" is a symbolic *cluster*.
105
106 Writes to concrete clusters can't affect other concrete clusters,
107 but can affect symbolic clusters; e.g. after:
108 verts[0].x = 42;
109 we bind 42 in the cluster for "verts", but the clusters for "b" and "c"
110 can't be affected. Any symbolic clusters for *p and for *q can be
111 affected, *p and *q could alias verts.
112
113 Writes to a symbolic cluster can affect other clusters, both
114 concrete and symbolic; e.g. after:
115 p->x = 17;
116 we bind 17 within the cluster for "*p". The concrete clusters for a, b,
117 c, and verts could be affected, depending on whether *p aliases them.
118 Similarly, the symbolic cluster to *q could be affected. */
119
120namespace ana {
121
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122/* A class for keeping track of aspects of a program_state that we don't
123 know about, to avoid false positives about leaks.
124
125 Consider:
126
127 p->field = malloc (1024);
128 q->field = NULL;
129
130 where we don't know whether or not p and q point to the same memory,
131 and:
132
133 p->field = malloc (1024);
134 unknown_fn (p);
135
136 In both cases, the svalue for the address of the allocated buffer
137 goes from being bound to p->field to not having anything explicitly bound
138 to it.
139
140 Given that we conservatively discard bindings due to possible aliasing or
141 calls to unknown function, the store loses references to svalues,
142 but these svalues could still be live. We don't want to warn about
143 them leaking - they're effectively in a "maybe live" state.
144
145 This "maybe live" information is somewhat transient.
146
147 We don't want to store this "maybe live" information in the program_state,
148 region_model, or store, since we don't want to bloat these objects (and
149 potentially bloat the exploded_graph with more nodes).
150 However, we can't store it in the region_model_context, as these context
151 objects sometimes don't last long enough to be around when comparing the
152 old vs the new state.
153
154 This class is a way to track a set of such svalues, so that we can
155 temporarily capture that they are in a "maybe live" state whilst
156 comparing old and new states. */
157
158class uncertainty_t
159{
160public:
161 typedef hash_set<const svalue *>::iterator iterator;
162
163 void on_maybe_bound_sval (const svalue *sval)
164 {
165 m_maybe_bound_svals.add (sval);
166 }
167 void on_mutable_sval_at_unknown_call (const svalue *sval)
168 {
169 m_mutable_at_unknown_call_svals.add (sval);
170 }
171
172 bool unknown_sm_state_p (const svalue *sval)
173 {
174 return (m_maybe_bound_svals.contains (sval)
175 || m_mutable_at_unknown_call_svals.contains (sval));
176 }
177
178 void dump_to_pp (pretty_printer *pp, bool simple) const;
179 void dump (bool simple) const;
180
181 iterator begin_maybe_bound_svals () const
182 {
183 return m_maybe_bound_svals.begin ();
184 }
185 iterator end_maybe_bound_svals () const
186 {
187 return m_maybe_bound_svals.end ();
188 }
189
190private:
191
192 /* svalues that might or might not still be bound. */
193 hash_set<const svalue *> m_maybe_bound_svals;
194
195 /* svalues that have mutable sm-state at unknown calls. */
196 hash_set<const svalue *> m_mutable_at_unknown_call_svals;
197};
198
7c6b354b 199class byte_range;
808f4dfe 200class concrete_binding;
33255ad3 201class symbolic_binding;
808f4dfe 202
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203/* Abstract base class for describing ranges of bits within a binding_map
204 that can have svalues bound to them. */
205
206class binding_key
207{
208public:
209 virtual ~binding_key () {}
210 virtual bool concrete_p () const = 0;
211 bool symbolic_p () const { return !concrete_p (); }
212
e61ffa20 213 static const binding_key *make (store_manager *mgr, const region *r);
808f4dfe 214
e61ffa20 215 virtual void dump_to_pp (pretty_printer *pp, bool simple) const = 0;
808f4dfe 216 void dump (bool simple) const;
809192e7 217 label_text get_desc (bool simple=true) const;
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218
219 static int cmp_ptrs (const void *, const void *);
220 static int cmp (const binding_key *, const binding_key *);
221
222 virtual const concrete_binding *dyn_cast_concrete_binding () const
223 { return NULL; }
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224 virtual const symbolic_binding *dyn_cast_symbolic_binding () const
225 { return NULL; }
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226};
227
7c6b354b
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228/* A concrete range of bits. */
229
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230struct bit_range
231{
232 bit_range (bit_offset_t start_bit_offset, bit_size_t size_in_bits)
233 : m_start_bit_offset (start_bit_offset),
234 m_size_in_bits (size_in_bits)
235 {}
236
237 void dump_to_pp (pretty_printer *pp) const;
ec3fafa9 238 void dump () const;
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239
240 bit_offset_t get_start_bit_offset () const
241 {
242 return m_start_bit_offset;
243 }
244 bit_offset_t get_next_bit_offset () const
245 {
246 return m_start_bit_offset + m_size_in_bits;
247 }
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248 bit_offset_t get_last_bit_offset () const
249 {
250 return get_next_bit_offset () - 1;
251 }
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252
253 bool contains_p (bit_offset_t offset) const
254 {
255 return (offset >= get_start_bit_offset ()
256 && offset < get_next_bit_offset ());
257 }
258
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259 bool contains_p (const bit_range &other, bit_range *out) const;
260
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261 bool operator== (const bit_range &other) const
262 {
263 return (m_start_bit_offset == other.m_start_bit_offset
264 && m_size_in_bits == other.m_size_in_bits);
265 }
266
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267 bool intersects_p (const bit_range &other) const
268 {
269 return (get_start_bit_offset () < other.get_next_bit_offset ()
270 && other.get_start_bit_offset () < get_next_bit_offset ());
271 }
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272 bool intersects_p (const bit_range &other,
273 bit_range *out_this,
274 bit_range *out_other) const;
d3b1ef7a 275
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276 static int cmp (const bit_range &br1, const bit_range &br2);
277
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278 bit_range operator- (bit_offset_t offset) const;
279
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280 static bool from_mask (unsigned HOST_WIDE_INT mask, bit_range *out);
281
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282 bool as_byte_range (byte_range *out) const;
283
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284 bit_offset_t m_start_bit_offset;
285 bit_size_t m_size_in_bits;
286};
287
7c6b354b
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288/* A concrete range of bytes. */
289
290struct byte_range
291{
292 byte_range (byte_offset_t start_byte_offset, byte_size_t size_in_bytes)
293 : m_start_byte_offset (start_byte_offset),
294 m_size_in_bytes (size_in_bytes)
295 {}
296
297 void dump_to_pp (pretty_printer *pp) const;
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298 void dump () const;
299
300 bool contains_p (byte_offset_t offset) const
301 {
302 return (offset >= get_start_byte_offset ()
303 && offset < get_next_byte_offset ());
304 }
305 bool contains_p (const byte_range &other, byte_range *out) const;
306
307 bool operator== (const byte_range &other) const
308 {
309 return (m_start_byte_offset == other.m_start_byte_offset
310 && m_size_in_bytes == other.m_size_in_bytes);
311 }
7c6b354b 312
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313 byte_offset_t get_start_byte_offset () const
314 {
315 return m_start_byte_offset;
316 }
317 byte_offset_t get_next_byte_offset () const
318 {
319 return m_start_byte_offset + m_size_in_bytes;
320 }
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321 byte_offset_t get_last_byte_offset () const
322 {
323 return m_start_byte_offset + m_size_in_bytes - 1;
324 }
325
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326 bit_range as_bit_range () const
327 {
328 return bit_range (m_start_byte_offset * BITS_PER_UNIT,
329 m_size_in_bytes * BITS_PER_UNIT);
330 }
331
332 static int cmp (const byte_range &br1, const byte_range &br2);
333
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334 byte_offset_t m_start_byte_offset;
335 byte_size_t m_size_in_bytes;
336};
337
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338/* Concrete subclass of binding_key, for describing a concrete range of
339 bits within the binding_map (e.g. "bits 8-15"). */
340
341class concrete_binding : public binding_key
342{
343public:
344 /* This class is its own key for the purposes of consolidation. */
345 typedef concrete_binding key_t;
346
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347 concrete_binding (bit_offset_t start_bit_offset, bit_size_t size_in_bits)
348 : m_bit_range (start_bit_offset, size_in_bits)
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349 {}
350 bool concrete_p () const FINAL OVERRIDE { return true; }
351
352 hashval_t hash () const
353 {
354 inchash::hash hstate;
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355 hstate.add_wide_int (m_bit_range.m_start_bit_offset);
356 hstate.add_wide_int (m_bit_range.m_size_in_bits);
e61ffa20 357 return hstate.end ();
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358 }
359 bool operator== (const concrete_binding &other) const
360 {
6b400aef 361 return m_bit_range == other.m_bit_range;
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362 }
363
364 void dump_to_pp (pretty_printer *pp, bool simple) const FINAL OVERRIDE;
365
366 const concrete_binding *dyn_cast_concrete_binding () const FINAL OVERRIDE
367 { return this; }
368
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369 const bit_range &get_bit_range () const { return m_bit_range; }
370
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371 bit_offset_t get_start_bit_offset () const
372 {
373 return m_bit_range.m_start_bit_offset;
374 }
375 bit_size_t get_size_in_bits () const
376 {
377 return m_bit_range.m_size_in_bits;
378 }
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379 /* Return the next bit offset after the end of this binding. */
380 bit_offset_t get_next_bit_offset () const
381 {
6b400aef 382 return m_bit_range.get_next_bit_offset ();
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383 }
384
385 bool overlaps_p (const concrete_binding &other) const;
386
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387 static int cmp_ptr_ptr (const void *, const void *);
388
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389 void mark_deleted () { m_bit_range.m_start_bit_offset = -1; }
390 void mark_empty () { m_bit_range.m_start_bit_offset = -2; }
391 bool is_deleted () const { return m_bit_range.m_start_bit_offset == -1; }
392 bool is_empty () const { return m_bit_range.m_start_bit_offset == -2; }
393
808f4dfe 394private:
6b400aef 395 bit_range m_bit_range;
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396};
397
398} // namespace ana
399
400template <> struct default_hash_traits<ana::concrete_binding>
401: public member_function_hash_traits<ana::concrete_binding>
402{
e61ffa20 403 static const bool empty_zero_p = false;
808f4dfe
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404};
405
406namespace ana {
407
408/* Concrete subclass of binding_key, for describing a symbolic set of
409 bits within the binding_map in terms of a region (e.g. "arr[i]"). */
410
411class symbolic_binding : public binding_key
412{
413public:
414 /* This class is its own key for the purposes of consolidation. */
415 typedef symbolic_binding key_t;
416
e61ffa20 417 symbolic_binding (const region *region) : m_region (region) {}
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418 bool concrete_p () const FINAL OVERRIDE { return false; }
419
420 hashval_t hash () const
421 {
e61ffa20 422 return (intptr_t)m_region;
808f4dfe
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423 }
424 bool operator== (const symbolic_binding &other) const
425 {
e61ffa20 426 return m_region == other.m_region;
808f4dfe
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427 }
428
429 void dump_to_pp (pretty_printer *pp, bool simple) const FINAL OVERRIDE;
430
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431 const symbolic_binding *dyn_cast_symbolic_binding () const FINAL OVERRIDE
432 { return this; }
433
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434 const region *get_region () const { return m_region; }
435
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436 static int cmp_ptr_ptr (const void *, const void *);
437
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438 void mark_deleted () { m_region = reinterpret_cast<const region *> (1); }
439 void mark_empty () { m_region = NULL; }
440 bool is_deleted () const
441 { return m_region == reinterpret_cast<const region *> (1); }
442 bool is_empty () const { return m_region == NULL; }
443
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444private:
445 const region *m_region;
446};
447
448} // namespace ana
449
450template <> struct default_hash_traits<ana::symbolic_binding>
451: public member_function_hash_traits<ana::symbolic_binding>
452{
453 static const bool empty_zero_p = true;
454};
455
456namespace ana {
457
458/* A mapping from binding_keys to svalues, for use by binding_cluster
459 and compound_svalue. */
460
461class binding_map
462{
463public:
464 typedef hash_map <const binding_key *, const svalue *> map_t;
465 typedef map_t::iterator iterator_t;
466
467 binding_map () : m_map () {}
468 binding_map (const binding_map &other);
469 binding_map& operator=(const binding_map &other);
470
471 bool operator== (const binding_map &other) const;
472 bool operator!= (const binding_map &other) const
473 {
474 return !(*this == other);
475 }
476
477 hashval_t hash () const;
478
479 const svalue *get (const binding_key *key) const
480 {
481 const svalue **slot = const_cast<map_t &> (m_map).get (key);
482 if (slot)
483 return *slot;
484 else
485 return NULL;
486 }
487 bool put (const binding_key *k, const svalue *v)
488 {
489 gcc_assert (v);
490 return m_map.put (k, v);
491 }
492
493 void remove (const binding_key *k) { m_map.remove (k); }
494 void empty () { m_map.empty (); }
495
496 iterator_t begin () const { return m_map.begin (); }
497 iterator_t end () const { return m_map.end (); }
498 size_t elements () const { return m_map.elements (); }
499
500 void dump_to_pp (pretty_printer *pp, bool simple, bool multiline) const;
501 void dump (bool simple) const;
502
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503 json::object *to_json () const;
504
18056e45 505 bool apply_ctor_to_region (const region *parent_reg, tree ctor,
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506 region_model_manager *mgr);
507
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508 static int cmp (const binding_map &map1, const binding_map &map2);
509
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510 void remove_overlapping_bindings (store_manager *mgr,
511 const binding_key *drop_key,
512 uncertainty_t *uncertainty);
513
808f4dfe 514private:
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515 void get_overlapping_bindings (const binding_key *key,
516 auto_vec<const binding_key *> *out);
18056e45 517 bool apply_ctor_val_to_range (const region *parent_reg,
0d1b4edc
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518 region_model_manager *mgr,
519 tree min_index, tree max_index,
520 tree val);
18056e45 521 bool apply_ctor_pair_to_child_region (const region *parent_reg,
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522 region_model_manager *mgr,
523 tree index, tree val);
524
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525 map_t m_map;
526};
527
528/* Concept: BindingVisitor, for use by binding_cluster::for_each_binding
529 and store::for_each_binding.
530
531 Should implement:
532 void on_binding (const binding_key *key, const svalue *&sval);
533*/
534
535/* All of the bindings within a store for regions that share the same
536 base region. */
537
538class binding_cluster
539{
540public:
541 friend class store;
542
543 typedef hash_map <const binding_key *, const svalue *> map_t;
544 typedef map_t::iterator iterator_t;
545
546 binding_cluster (const region *base_region)
547 : m_base_region (base_region), m_map (),
548 m_escaped (false), m_touched (false) {}
549 binding_cluster (const binding_cluster &other);
550 binding_cluster& operator=(const binding_cluster &other);
551
552 bool operator== (const binding_cluster &other) const;
553 bool operator!= (const binding_cluster &other) const
554 {
555 return !(*this == other);
556 }
557
558 hashval_t hash () const;
559
560 bool symbolic_p () const;
561
562 void dump_to_pp (pretty_printer *pp, bool simple, bool multiline) const;
563 void dump (bool simple) const;
564
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565 void validate () const;
566
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567 json::object *to_json () const;
568
e61ffa20 569 void bind (store_manager *mgr, const region *, const svalue *);
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570
571 void clobber_region (store_manager *mgr, const region *reg);
572 void purge_region (store_manager *mgr, const region *reg);
e61ffa20 573 void fill_region (store_manager *mgr, const region *reg, const svalue *sval);
808f4dfe 574 void zero_fill_region (store_manager *mgr, const region *reg);
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575 void mark_region_as_unknown (store_manager *mgr, const region *reg,
576 uncertainty_t *uncertainty);
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577 void purge_state_involving (const svalue *sval,
578 region_model_manager *sval_mgr);
808f4dfe 579
e61ffa20 580 const svalue *get_binding (store_manager *mgr, const region *reg) const;
808f4dfe 581 const svalue *get_binding_recursive (store_manager *mgr,
e61ffa20 582 const region *reg) const;
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583 const svalue *get_any_binding (store_manager *mgr,
584 const region *reg) const;
585 const svalue *maybe_get_compound_binding (store_manager *mgr,
586 const region *reg) const;
587
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588 void remove_overlapping_bindings (store_manager *mgr, const region *reg,
589 uncertainty_t *uncertainty);
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590
591 template <typename T>
592 void for_each_value (void (*cb) (const svalue *sval, T user_data),
8a18261a 593 T user_data) const
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594 {
595 for (map_t::iterator iter = m_map.begin (); iter != m_map.end (); ++iter)
596 cb ((*iter).second, user_data);
597 }
598
599 static bool can_merge_p (const binding_cluster *cluster_a,
600 const binding_cluster *cluster_b,
601 binding_cluster *out_cluster,
be6c485b 602 store *out_store,
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603 store_manager *mgr,
604 model_merger *merger);
605 void make_unknown_relative_to (const binding_cluster *other_cluster,
be6c485b 606 store *out_store,
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607 store_manager *mgr);
608
609 void mark_as_escaped ();
610 void on_unknown_fncall (const gcall *call, store_manager *mgr);
ded2c2c0 611 void on_asm (const gasm *stmt, store_manager *mgr);
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612
613 bool escaped_p () const { return m_escaped; }
614 bool touched_p () const { return m_touched; }
615
616 bool redundant_p () const;
617 bool empty_p () const { return m_map.elements () == 0; }
618
619 void get_representative_path_vars (const region_model *model,
620 svalue_set *visited,
621 const region *base_reg,
622 const svalue *sval,
623 auto_vec<path_var> *out_pvs) const;
624
625 const svalue *maybe_get_simple_value (store_manager *mgr) const;
626
627 template <typename BindingVisitor>
8a18261a 628 void for_each_binding (BindingVisitor &v) const
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629 {
630 for (map_t::iterator iter = m_map.begin (); iter != m_map.end (); ++iter)
631 {
632 const binding_key *key = (*iter).first;
633 const svalue *&sval = (*iter).second;
634 v.on_binding (key, sval);
635 }
636 }
637
638 iterator_t begin () const { return m_map.begin (); }
639 iterator_t end () const { return m_map.end (); }
640
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641 const binding_map &get_map () const { return m_map; }
642
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643private:
644 const svalue *get_any_value (const binding_key *key) const;
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645 void bind_compound_sval (store_manager *mgr,
646 const region *reg,
647 const compound_svalue *compound_sval);
648 void bind_key (const binding_key *key, const svalue *sval);
649
650 const region *m_base_region;
651
652 binding_map m_map;
653
654 /* Has a pointer to this cluster "escaped" into a part of the program
655 we don't know about (via a call to a function with an unknown body,
656 or by being passed in as a pointer param of a "top-level" function call).
657 Such regions could be overwritten when other such functions are called,
658 even if the region is no longer reachable by pointers that we are
659 tracking. */
660 bool m_escaped;
661
662 /* Has this cluster been written to via a symbolic binding?
663 If so, then we don't know anything about unbound subregions,
664 so we can't use initial_svalue, treat them as uninitialized, or
665 inherit values from a parent region. */
666 bool m_touched;
667};
668
669/* The mapping from regions to svalues.
670 This is actually expressed by subdividing into clusters, to better
671 handle aliasing. */
672
673class store
674{
675public:
676 typedef hash_map <const region *, binding_cluster *> cluster_map_t;
677
678 store ();
679 store (const store &other);
680 ~store ();
681
682 store &operator= (const store &other);
683
684 bool operator== (const store &other) const;
685 bool operator!= (const store &other) const
686 {
687 return !(*this == other);
688 }
689
690 hashval_t hash () const;
691
692 void dump_to_pp (pretty_printer *pp, bool summarize, bool multiline,
693 store_manager *mgr) const;
694 void dump (bool simple) const;
695 void summarize_to_pp (pretty_printer *pp, bool simple) const;
696
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697 void validate () const;
698
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699 json::object *to_json () const;
700
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701 const svalue *get_any_binding (store_manager *mgr, const region *reg) const;
702
703 bool called_unknown_fn_p () const { return m_called_unknown_fn; }
704
705 void set_value (store_manager *mgr, const region *lhs_reg,
e61ffa20 706 const svalue *rhs_sval,
3a66c289 707 uncertainty_t *uncertainty);
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708 void clobber_region (store_manager *mgr, const region *reg);
709 void purge_region (store_manager *mgr, const region *reg);
e61ffa20 710 void fill_region (store_manager *mgr, const region *reg, const svalue *sval);
808f4dfe 711 void zero_fill_region (store_manager *mgr, const region *reg);
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712 void mark_region_as_unknown (store_manager *mgr, const region *reg,
713 uncertainty_t *uncertainty);
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714 void purge_state_involving (const svalue *sval,
715 region_model_manager *sval_mgr);
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716
717 const binding_cluster *get_cluster (const region *base_reg) const;
718 binding_cluster *get_cluster (const region *base_reg);
719 binding_cluster *get_or_create_cluster (const region *base_reg);
720 void purge_cluster (const region *base_reg);
721
722 template <typename T>
723 void for_each_cluster (void (*cb) (const region *base_reg, T user_data),
724 T user_data) const
725 {
726 for (cluster_map_t::iterator iter = m_cluster_map.begin ();
727 iter != m_cluster_map.end (); ++iter)
728 cb ((*iter).first, user_data);
729 }
730
731 static bool can_merge_p (const store *store_a, const store *store_b,
732 store *out_store, store_manager *mgr,
733 model_merger *merger);
734
735 void mark_as_escaped (const region *base_reg);
736 void on_unknown_fncall (const gcall *call, store_manager *mgr);
737 bool escaped_p (const region *reg) const;
738
739 void get_representative_path_vars (const region_model *model,
740 svalue_set *visited,
741 const svalue *sval,
742 auto_vec<path_var> *out_pvs) const;
743
744 cluster_map_t::iterator begin () const { return m_cluster_map.begin (); }
745 cluster_map_t::iterator end () const { return m_cluster_map.end (); }
746
747 tristate eval_alias (const region *base_reg_a,
c199723d 748 const region *base_reg_b) const;
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749
750 template <typename BindingVisitor>
751 void for_each_binding (BindingVisitor &v)
752 {
753 for (cluster_map_t::iterator iter = m_cluster_map.begin ();
754 iter != m_cluster_map.end (); ++iter)
755 (*iter).second->for_each_binding (v);
756 }
757
758 void canonicalize (store_manager *mgr);
759 void loop_replay_fixup (const store *other_store,
760 region_model_manager *mgr);
761
762private:
763 void remove_overlapping_bindings (store_manager *mgr, const region *reg);
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764 tristate eval_alias_1 (const region *base_reg_a,
765 const region *base_reg_b) const;
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766
767 cluster_map_t m_cluster_map;
768
769 /* If this is true, then unknown code has been called, and so
770 any global variable that isn't currently modelled by the store
771 has unknown state, rather than being in an "initial state".
772 This is to avoid having to mark (and thus explicitly track)
773 every global when an unknown function is called; instead, they
774 can be tracked implicitly. */
775 bool m_called_unknown_fn;
776};
777
778/* A class responsible for owning and consolidating binding keys
779 (both concrete and symbolic).
780 Key instances are immutable as far as clients are concerned, so they
781 are provided as "const" ptrs. */
782
783class store_manager
784{
785public:
786 store_manager (region_model_manager *mgr) : m_mgr (mgr) {}
787
788 /* binding consolidation. */
789 const concrete_binding *
790 get_concrete_binding (bit_offset_t start_bit_offset,
e61ffa20 791 bit_offset_t size_in_bits);
d3b1ef7a 792 const concrete_binding *
e61ffa20 793 get_concrete_binding (const bit_range &bits)
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794 {
795 return get_concrete_binding (bits.get_start_bit_offset (),
e61ffa20 796 bits.m_size_in_bits);
d3b1ef7a 797 }
808f4dfe 798 const symbolic_binding *
e61ffa20 799 get_symbolic_binding (const region *region);
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800
801 region_model_manager *get_svalue_manager () const
802 {
803 return m_mgr;
804 }
805
806 void log_stats (logger *logger, bool show_objs) const;
807
808private:
809 region_model_manager *m_mgr;
810 consolidation_map<concrete_binding> m_concrete_binding_key_mgr;
811 consolidation_map<symbolic_binding> m_symbolic_binding_key_mgr;
812};
813
814} // namespace ana
815
816#endif /* GCC_ANALYZER_STORE_H */