Coverage Report

Created: 2020-09-22 08:39

/Users/buildslave/jenkins/workspace/coverage/llvm-project/clang/lib/StaticAnalyzer/Core/RegionStore.cpp
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//== RegionStore.cpp - Field-sensitive store model --------------*- C++ -*--==//
2
//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4
// See https://llvm.org/LICENSE.txt for license information.
5
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6
//
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//===----------------------------------------------------------------------===//
8
//
9
// This file defines a basic region store model. In this model, we do have field
10
// sensitivity. But we assume nothing about the heap shape. So recursive data
11
// structures are largely ignored. Basically we do 1-limiting analysis.
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// Parameter pointers are assumed with no aliasing. Pointee objects of
13
// parameters are created lazily.
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//
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//===----------------------------------------------------------------------===//
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17
#include "clang/AST/Attr.h"
18
#include "clang/AST/CharUnits.h"
19
#include "clang/ASTMatchers/ASTMatchFinder.h"
20
#include "clang/Analysis/Analyses/LiveVariables.h"
21
#include "clang/Analysis/AnalysisDeclContext.h"
22
#include "clang/Basic/JsonSupport.h"
23
#include "clang/Basic/TargetInfo.h"
24
#include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
25
#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
26
#include "clang/StaticAnalyzer/Core/PathSensitive/DynamicSize.h"
27
#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
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#include "llvm/ADT/ImmutableMap.h"
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#include "llvm/ADT/Optional.h"
33
#include "llvm/Support/raw_ostream.h"
34
#include <utility>
35
36
using namespace clang;
37
using namespace ento;
38
39
//===----------------------------------------------------------------------===//
40
// Representation of binding keys.
41
//===----------------------------------------------------------------------===//
42
43
namespace {
44
class BindingKey {
45
public:
46
  enum Kind { Default = 0x0, Direct = 0x1 };
47
private:
48
  enum { Symbolic = 0x2 };
49
50
  llvm::PointerIntPair<const MemRegion *, 2> P;
51
  uint64_t Data;
52
53
  /// Create a key for a binding to region \p r, which has a symbolic offset
54
  /// from region \p Base.
55
  explicit BindingKey(const SubRegion *r, const SubRegion *Base, Kind k)
56
90.8k
    : P(r, k | Symbolic), Data(reinterpret_cast<uintptr_t>(Base)) {
57
90.8k
    assert(r && Base && "Must have known regions.");
58
90.8k
    assert(getConcreteOffsetRegion() == Base && "Failed to store base region");
59
90.8k
  }
60
61
  /// Create a key for a binding at \p offset from base region \p r.
62
  explicit BindingKey(const MemRegion *r, uint64_t offset, Kind k)
63
1.42M
    : P(r, k), Data(offset) {
64
1.42M
    assert(r && "Must have known regions.");
65
1.42M
    assert(getOffset() == offset && "Failed to store offset");
66
1.42M
    assert((r == r->getBaseRegion() || isa<ObjCIvarRegion>(r) ||
67
1.42M
            isa <CXXDerivedObjectRegion>(r)) &&
68
1.42M
           "Not a base");
69
1.42M
  }
70
public:
71
72
377k
  bool isDirect() const { return P.getInt() & Direct; }
73
3.46M
  bool hasSymbolicOffset() const { return P.getInt() & Symbolic; }
74
75
3.26M
  const MemRegion *getRegion() const { return P.getPointer(); }
76
1.68M
  uint64_t getOffset() const {
77
1.68M
    assert(!hasSymbolicOffset());
78
1.68M
    return Data;
79
1.68M
  }
80
81
182k
  const SubRegion *getConcreteOffsetRegion() const {
82
182k
    assert(hasSymbolicOffset());
83
182k
    return reinterpret_cast<const SubRegion *>(static_cast<uintptr_t>(Data));
84
182k
  }
85
86
1.51M
  const MemRegion *getBaseRegion() const {
87
1.51M
    if (hasSymbolicOffset())
88
90.8k
      return getConcreteOffsetRegion()->getBaseRegion();
89
1.42M
    return getRegion()->getBaseRegion();
90
1.42M
  }
91
92
315k
  void Profile(llvm::FoldingSetNodeID& ID) const {
93
315k
    ID.AddPointer(P.getOpaqueValue());
94
315k
    ID.AddInteger(Data);
95
315k
  }
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97
  static BindingKey Make(const MemRegion *R, Kind k);
98
99
126k
  bool operator<(const BindingKey &X) const {
100
126k
    if (P.getOpaqueValue() < X.P.getOpaqueValue())
101
48.4k
      return true;
102
77.6k
    if (P.getOpaqueValue() > X.P.getOpaqueValue())
103
23.9k
      return false;
104
53.6k
    return Data < X.Data;
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53.6k
  }
106
107
653k
  bool operator==(const BindingKey &X) const {
108
653k
    return P.getOpaqueValue() == X.P.getOpaqueValue() &&
109
580k
           Data == X.Data;
110
653k
  }
111
112
  LLVM_DUMP_METHOD void dump() const;
113
};
114
} // end anonymous namespace
115
116
1.51M
BindingKey BindingKey::Make(const MemRegion *R, Kind k) {
117
1.51M
  const RegionOffset &RO = R->getAsOffset();
118
1.51M
  if (RO.hasSymbolicOffset())
119
90.8k
    return BindingKey(cast<SubRegion>(R), cast<SubRegion>(RO.getRegion()), k);
120
121
1.42M
  return BindingKey(RO.getRegion(), RO.getOffset(), k);
122
1.42M
}
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namespace llvm {
125
154
static inline raw_ostream &operator<<(raw_ostream &Out, BindingKey K) {
126
94
  Out << "\"kind\": \"" << (K.isDirect() ? "Direct" : 
"Default"60
)
127
154
      << "\", \"offset\": ";
128
129
154
  if (!K.hasSymbolicOffset())
130
154
    Out << K.getOffset();
131
0
  else
132
0
    Out << "null";
133
134
154
  return Out;
135
154
}
136
137
} // namespace llvm
138
139
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
140
0
void BindingKey::dump() const { llvm::errs() << *this; }
141
#endif
142
143
//===----------------------------------------------------------------------===//
144
// Actual Store type.
145
//===----------------------------------------------------------------------===//
146
147
typedef llvm::ImmutableMap<BindingKey, SVal>    ClusterBindings;
148
typedef llvm::ImmutableMapRef<BindingKey, SVal> ClusterBindingsRef;
149
typedef std::pair<BindingKey, SVal> BindingPair;
150
151
typedef llvm::ImmutableMap<const MemRegion *, ClusterBindings>
152
        RegionBindings;
153
154
namespace {
155
class RegionBindingsRef : public llvm::ImmutableMapRef<const MemRegion *,
156
                                 ClusterBindings> {
157
  ClusterBindings::Factory *CBFactory;
158
159
  // This flag indicates whether the current bindings are within the analysis
160
  // that has started from main(). It affects how we perform loads from
161
  // global variables that have initializers: if we have observed the
162
  // program execution from the start and we know that these variables
163
  // have not been overwritten yet, we can be sure that their initializers
164
  // are still relevant. This flag never gets changed when the bindings are
165
  // updated, so it could potentially be moved into RegionStoreManager
166
  // (as if it's the same bindings but a different loading procedure)
167
  // however that would have made the manager needlessly stateful.
168
  bool IsMainAnalysis;
169
170
public:
171
  typedef llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>
172
          ParentTy;
173
174
  RegionBindingsRef(ClusterBindings::Factory &CBFactory,
175
                    const RegionBindings::TreeTy *T,
176
                    RegionBindings::TreeTy::Factory *F,
177
                    bool IsMainAnalysis)
178
      : llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>(T, F),
179
11.7M
        CBFactory(&CBFactory), IsMainAnalysis(IsMainAnalysis) {}
180
181
  RegionBindingsRef(const ParentTy &P,
182
                    ClusterBindings::Factory &CBFactory,
183
                    bool IsMainAnalysis)
184
      : llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>(P),
185
596k
        CBFactory(&CBFactory), IsMainAnalysis(IsMainAnalysis) {}
186
187
286k
  RegionBindingsRef add(key_type_ref K, data_type_ref D) const {
188
286k
    return RegionBindingsRef(static_cast<const ParentTy *>(this)->add(K, D),
189
286k
                             *CBFactory, IsMainAnalysis);
190
286k
  }
191
192
296k
  RegionBindingsRef remove(key_type_ref K) const {
193
296k
    return RegionBindingsRef(static_cast<const ParentTy *>(this)->remove(K),
194
296k
                             *CBFactory, IsMainAnalysis);
195
296k
  }
196
197
  RegionBindingsRef addBinding(BindingKey K, SVal V) const;
198
199
  RegionBindingsRef addBinding(const MemRegion *R,
200
                               BindingKey::Kind k, SVal V) const;
201
202
  const SVal *lookup(BindingKey K) const;
203
  const SVal *lookup(const MemRegion *R, BindingKey::Kind k) const;
204
  using llvm::ImmutableMapRef<const MemRegion *, ClusterBindings>::lookup;
205
206
  RegionBindingsRef removeBinding(BindingKey K);
207
208
  RegionBindingsRef removeBinding(const MemRegion *R,
209
                                  BindingKey::Kind k);
210
211
60.5k
  RegionBindingsRef removeBinding(const MemRegion *R) {
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60.5k
    return removeBinding(R, BindingKey::Direct).
213
60.5k
           removeBinding(R, BindingKey::Default);
214
60.5k
  }
215
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  Optional<SVal> getDirectBinding(const MemRegion *R) const;
217
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  /// getDefaultBinding - Returns an SVal* representing an optional default
219
  ///  binding associated with a region and its subregions.
220
  Optional<SVal> getDefaultBinding(const MemRegion *R) const;
221
222
  /// Return the internal tree as a Store.
223
636k
  Store asStore() const {
224
636k
    llvm::PointerIntPair<Store, 1, bool> Ptr = {
225
636k
        asImmutableMap().getRootWithoutRetain(), IsMainAnalysis};
226
636k
    return reinterpret_cast<Store>(Ptr.getOpaqueValue());
227
636k
  }
228
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24.7k
  bool isMainAnalysis() const {
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24.7k
    return IsMainAnalysis;
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24.7k
  }
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  void printJson(raw_ostream &Out, const char *NL = "\n",
234
86
                 unsigned int Space = 0, bool IsDot = false) const {
235
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    for (iterator I = begin(); I != end(); 
++I150
) {
236
      // TODO: We might need a .printJson for I.getKey() as well.
237
150
      Indent(Out, Space, IsDot)
238
150
          << "{ \"cluster\": \"" << I.getKey() << "\", \"pointer\": \""
239
150
          << (const void *)I.getKey() << "\", \"items\": [" << NL;
240
241
150
      ++Space;
242
150
      const ClusterBindings &CB = I.getData();
243
304
      for (ClusterBindings::iterator CI = CB.begin(); CI != CB.end(); 
++CI154
) {
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154
        Indent(Out, Space, IsDot) << "{ " << CI.getKey() << ", \"value\": ";
245
154
        CI.getData().printJson(Out, /*AddQuotes=*/true);
246
154
        Out << " }";
247
154
        if (std::next(CI) != CB.end())
248
4
          Out << ',';
249
154
        Out << NL;
250
154
      }
251
252
150
      --Space;
253
150
      Indent(Out, Space, IsDot) << "]}";
254
150
      if (std::next(I) != end())
255
64
        Out << ',';
256
150
      Out << NL;
257
150
    }
258
86
  }
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260
0
  LLVM_DUMP_METHOD void dump() const { printJson(llvm::errs()); }
261
};
262
} // end anonymous namespace
263
264
typedef const RegionBindingsRef& RegionBindingsConstRef;
265
266
416k
Optional<SVal> RegionBindingsRef::getDirectBinding(const MemRegion *R) const {
267
416k
  return Optional<SVal>::create(lookup(R, BindingKey::Direct));
268
416k
}
269
270
477k
Optional<SVal> RegionBindingsRef::getDefaultBinding(const MemRegion *R) const {
271
477k
  return Optional<SVal>::create(lookup(R, BindingKey::Default));
272
477k
}
273
274
265k
RegionBindingsRef RegionBindingsRef::addBinding(BindingKey K, SVal V) const {
275
265k
  const MemRegion *Base = K.getBaseRegion();
276
277
265k
  const ClusterBindings *ExistingCluster = lookup(Base);
278
265k
  ClusterBindings Cluster =
279
243k
      (ExistingCluster ? 
*ExistingCluster21.7k
: CBFactory->getEmptyMap());
280
281
265k
  ClusterBindings NewCluster = CBFactory->add(Cluster, K, V);
282
265k
  return add(Base, NewCluster);
283
265k
}
284
285
286
RegionBindingsRef RegionBindingsRef::addBinding(const MemRegion *R,
287
                                                BindingKey::Kind k,
288
28.7k
                                                SVal V) const {
289
28.7k
  return addBinding(BindingKey::Make(R, k), V);
290
28.7k
}
291
292
954k
const SVal *RegionBindingsRef::lookup(BindingKey K) const {
293
954k
  const ClusterBindings *Cluster = lookup(K.getBaseRegion());
294
954k
  if (!Cluster)
295
586k
    return nullptr;
296
367k
  return Cluster->lookup(K);
297
367k
}
298
299
const SVal *RegionBindingsRef::lookup(const MemRegion *R,
300
954k
                                      BindingKey::Kind k) const {
301
954k
  return lookup(BindingKey::Make(R, k));
302
954k
}
303
304
121k
RegionBindingsRef RegionBindingsRef::removeBinding(BindingKey K) {
305
121k
  const MemRegion *Base = K.getBaseRegion();
306
121k
  const ClusterBindings *Cluster = lookup(Base);
307
121k
  if (!Cluster)
308
121k
    return *this;
309
310
89
  ClusterBindings NewCluster = CBFactory->remove(*Cluster, K);
311
89
  if (NewCluster.isEmpty())
312
4
    return remove(Base);
313
85
  return add(Base, NewCluster);
314
85
}
315
316
RegionBindingsRef RegionBindingsRef::removeBinding(const MemRegion *R,
317
121k
                                                BindingKey::Kind k){
318
121k
  return removeBinding(BindingKey::Make(R, k));
319
121k
}
320
321
//===----------------------------------------------------------------------===//
322
// Fine-grained control of RegionStoreManager.
323
//===----------------------------------------------------------------------===//
324
325
namespace {
326
struct minimal_features_tag {};
327
struct maximal_features_tag {};
328
329
class RegionStoreFeatures {
330
  bool SupportsFields;
331
public:
332
  RegionStoreFeatures(minimal_features_tag) :
333
0
    SupportsFields(false) {}
334
335
  RegionStoreFeatures(maximal_features_tag) :
336
13.6k
    SupportsFields(true) {}
337
338
0
  void enableFields(bool t) { SupportsFields = t; }
339
340
23.6k
  bool supportsFields() const { return SupportsFields; }
341
};
342
}
343
344
//===----------------------------------------------------------------------===//
345
// Main RegionStore logic.
346
//===----------------------------------------------------------------------===//
347
348
namespace {
349
class InvalidateRegionsWorker;
350
351
class RegionStoreManager : public StoreManager {
352
public:
353
  const RegionStoreFeatures Features;
354
355
  RegionBindings::Factory RBFactory;
356
  mutable ClusterBindings::Factory CBFactory;
357
358
  typedef std::vector<SVal> SValListTy;
359
private:
360
  typedef llvm::DenseMap<const LazyCompoundValData *,
361
                         SValListTy> LazyBindingsMapTy;
362
  LazyBindingsMapTy LazyBindingsMap;
363
364
  /// The largest number of fields a struct can have and still be
365
  /// considered "small".
366
  ///
367
  /// This is currently used to decide whether or not it is worth "forcing" a
368
  /// LazyCompoundVal on bind.
369
  ///
370
  /// This is controlled by 'region-store-small-struct-limit' option.
371
  /// To disable all small-struct-dependent behavior, set the option to "0".
372
  unsigned SmallStructLimit;
373
374
  /// A helper used to populate the work list with the given set of
375
  /// regions.
376
  void populateWorkList(InvalidateRegionsWorker &W,
377
                        ArrayRef<SVal> Values,
378
                        InvalidatedRegions *TopLevelRegions);
379
380
public:
381
  RegionStoreManager(ProgramStateManager& mgr, const RegionStoreFeatures &f)
382
    : StoreManager(mgr), Features(f),
383
      RBFactory(mgr.getAllocator()), CBFactory(mgr.getAllocator()),
384
13.6k
      SmallStructLimit(0) {
385
13.6k
    ExprEngine &Eng = StateMgr.getOwningEngine();
386
13.6k
    AnalyzerOptions &Options = Eng.getAnalysisManager().options;
387
13.6k
    SmallStructLimit = Options.RegionStoreSmallStructLimit;
388
13.6k
  }
389
390
391
  /// setImplicitDefaultValue - Set the default binding for the provided
392
  ///  MemRegion to the value implicitly defined for compound literals when
393
  ///  the value is not specified.
394
  RegionBindingsRef setImplicitDefaultValue(RegionBindingsConstRef B,
395
                                            const MemRegion *R, QualType T);
396
397
  /// ArrayToPointer - Emulates the "decay" of an array to a pointer
398
  ///  type.  'Array' represents the lvalue of the array being decayed
399
  ///  to a pointer, and the returned SVal represents the decayed
400
  ///  version of that lvalue (i.e., a pointer to the first element of
401
  ///  the array).  This is called by ExprEngine when evaluating
402
  ///  casts from arrays to pointers.
403
  SVal ArrayToPointer(Loc Array, QualType ElementTy) override;
404
405
  /// Creates the Store that correctly represents memory contents before
406
  /// the beginning of the analysis of the given top-level stack frame.
407
13.6k
  StoreRef getInitialStore(const LocationContext *InitLoc) override {
408
13.6k
    bool IsMainAnalysis = false;
409
13.6k
    if (const auto *FD = dyn_cast<FunctionDecl>(InitLoc->getDecl()))
410
12.4k
      IsMainAnalysis = FD->isMain() && 
!Ctx.getLangOpts().CPlusPlus59
;
411
13.6k
    return StoreRef(RegionBindingsRef(
412
13.6k
        RegionBindingsRef::ParentTy(RBFactory.getEmptyMap(), RBFactory),
413
13.6k
        CBFactory, IsMainAnalysis).asStore(), *this);
414
13.6k
  }
415
416
  //===-------------------------------------------------------------------===//
417
  // Binding values to regions.
418
  //===-------------------------------------------------------------------===//
419
  RegionBindingsRef invalidateGlobalRegion(MemRegion::Kind K,
420
                                           const Expr *Ex,
421
                                           unsigned Count,
422
                                           const LocationContext *LCtx,
423
                                           RegionBindingsRef B,
424
                                           InvalidatedRegions *Invalidated);
425
426
  StoreRef invalidateRegions(Store store,
427
                             ArrayRef<SVal> Values,
428
                             const Expr *E, unsigned Count,
429
                             const LocationContext *LCtx,
430
                             const CallEvent *Call,
431
                             InvalidatedSymbols &IS,
432
                             RegionAndSymbolInvalidationTraits &ITraits,
433
                             InvalidatedRegions *Invalidated,
434
                             InvalidatedRegions *InvalidatedTopLevel) override;
435
436
  bool scanReachableSymbols(Store S, const MemRegion *R,
437
                            ScanReachableSymbols &Callbacks) override;
438
439
  RegionBindingsRef removeSubRegionBindings(RegionBindingsConstRef B,
440
                                            const SubRegion *R);
441
442
public: // Part of public interface to class.
443
444
172k
  StoreRef Bind(Store store, Loc LV, SVal V) override {
445
172k
    return StoreRef(bind(getRegionBindings(store), LV, V).asStore(), *this);
446
172k
  }
447
448
  RegionBindingsRef bind(RegionBindingsConstRef B, Loc LV, SVal V);
449
450
  // BindDefaultInitial is only used to initialize a region with
451
  // a default value.
452
  StoreRef BindDefaultInitial(Store store, const MemRegion *R,
453
748
                              SVal V) override {
454
748
    RegionBindingsRef B = getRegionBindings(store);
455
    // Use other APIs when you have to wipe the region that was initialized
456
    // earlier.
457
748
    assert(!(B.getDefaultBinding(R) || B.getDirectBinding(R)) &&
458
748
           "Double initialization!");
459
748
    B = B.addBinding(BindingKey::Make(R, BindingKey::Default), V);
460
748
    return StoreRef(B.asImmutableMap().getRootWithoutRetain(), *this);
461
748
  }
462
463
  // BindDefaultZero is used for zeroing constructors that may accidentally
464
  // overwrite existing bindings.
465
2.04k
  StoreRef BindDefaultZero(Store store, const MemRegion *R) override {
466
    // FIXME: The offsets of empty bases can be tricky because of
467
    // of the so called "empty base class optimization".
468
    // If a base class has been optimized out
469
    // we should not try to create a binding, otherwise we should.
470
    // Unfortunately, at the moment ASTRecordLayout doesn't expose
471
    // the actual sizes of the empty bases
472
    // and trying to infer them from offsets/alignments
473
    // seems to be error-prone and non-trivial because of the trailing padding.
474
    // As a temporary mitigation we don't create bindings for empty bases.
475
2.04k
    if (const auto *BR = dyn_cast<CXXBaseObjectRegion>(R))
476
16
      if (BR->getDecl()->isEmpty())
477
4
        return StoreRef(store, *this);
478
479
2.03k
    RegionBindingsRef B = getRegionBindings(store);
480
2.03k
    SVal V = svalBuilder.makeZeroVal(Ctx.CharTy);
481
2.03k
    B = removeSubRegionBindings(B, cast<SubRegion>(R));
482
2.03k
    B = B.addBinding(BindingKey::Make(R, BindingKey::Default), V);
483
2.03k
    return StoreRef(B.asImmutableMap().getRootWithoutRetain(), *this);
484
2.03k
  }
485
486
  /// Attempt to extract the fields of \p LCV and bind them to the struct region
487
  /// \p R.
488
  ///
489
  /// This path is used when it seems advantageous to "force" loading the values
490
  /// within a LazyCompoundVal to bind memberwise to the struct region, rather
491
  /// than using a Default binding at the base of the entire region. This is a
492
  /// heuristic attempting to avoid building long chains of LazyCompoundVals.
493
  ///
494
  /// \returns The updated store bindings, or \c None if binding non-lazily
495
  ///          would be too expensive.
496
  Optional<RegionBindingsRef> tryBindSmallStruct(RegionBindingsConstRef B,
497
                                                 const TypedValueRegion *R,
498
                                                 const RecordDecl *RD,
499
                                                 nonloc::LazyCompoundVal LCV);
500
501
  /// BindStruct - Bind a compound value to a structure.
502
  RegionBindingsRef bindStruct(RegionBindingsConstRef B,
503
                               const TypedValueRegion* R, SVal V);
504
505
  /// BindVector - Bind a compound value to a vector.
506
  RegionBindingsRef bindVector(RegionBindingsConstRef B,
507
                               const TypedValueRegion* R, SVal V);
508
509
  RegionBindingsRef bindArray(RegionBindingsConstRef B,
510
                              const TypedValueRegion* R,
511
                              SVal V);
512
513
  /// Clears out all bindings in the given region and assigns a new value
514
  /// as a Default binding.
515
  RegionBindingsRef bindAggregate(RegionBindingsConstRef B,
516
                                  const TypedRegion *R,
517
                                  SVal DefaultVal);
518
519
  /// Create a new store with the specified binding removed.
520
  /// \param ST the original store, that is the basis for the new store.
521
  /// \param L the location whose binding should be removed.
522
  StoreRef killBinding(Store ST, Loc L) override;
523
524
5.41M
  void incrementReferenceCount(Store store) override {
525
5.41M
    getRegionBindings(store).manualRetain();
526
5.41M
  }
527
528
  /// If the StoreManager supports it, decrement the reference count of
529
  /// the specified Store object.  If the reference count hits 0, the memory
530
  /// associated with the object is recycled.
531
4.33M
  void decrementReferenceCount(Store store) override {
532
4.33M
    getRegionBindings(store).manualRelease();
533
4.33M
  }
534
535
  bool includedInBindings(Store store, const MemRegion *region) const override;
536
537
  /// Return the value bound to specified location in a given state.
538
  ///
539
  /// The high level logic for this method is this:
540
  /// getBinding (L)
541
  ///   if L has binding
542
  ///     return L's binding
543
  ///   else if L is in killset
544
  ///     return unknown
545
  ///   else
546
  ///     if L is on stack or heap
547
  ///       return undefined
548
  ///     else
549
  ///       return symbolic
550
514k
  SVal getBinding(Store S, Loc L, QualType T) override {
551
514k
    return getBinding(getRegionBindings(S), L, T);
552
514k
  }
553
554
15
  Optional<SVal> getDefaultBinding(Store S, const MemRegion *R) override {
555
15
    RegionBindingsRef B = getRegionBindings(S);
556
    // Default bindings are always applied over a base region so look up the
557
    // base region's default binding, otherwise the lookup will fail when R
558
    // is at an offset from R->getBaseRegion().
559
15
    return B.getDefaultBinding(R->getBaseRegion());
560
15
  }
561
562
  SVal getBinding(RegionBindingsConstRef B, Loc L, QualType T = QualType());
563
564
  SVal getBindingForElement(RegionBindingsConstRef B, const ElementRegion *R);
565
566
  SVal getBindingForField(RegionBindingsConstRef B, const FieldRegion *R);
567
568
  SVal getBindingForObjCIvar(RegionBindingsConstRef B, const ObjCIvarRegion *R);
569
570
  SVal getBindingForVar(RegionBindingsConstRef B, const VarRegion *R);
571
572
  SVal getBindingForLazySymbol(const TypedValueRegion *R);
573
574
  SVal getBindingForFieldOrElementCommon(RegionBindingsConstRef B,
575
                                         const TypedValueRegion *R,
576
                                         QualType Ty);
577
578
  SVal getLazyBinding(const SubRegion *LazyBindingRegion,
579
                      RegionBindingsRef LazyBinding);
580
581
  /// Get bindings for the values in a struct and return a CompoundVal, used
582
  /// when doing struct copy:
583
  /// struct s x, y;
584
  /// x = y;
585
  /// y's value is retrieved by this method.
586
  SVal getBindingForStruct(RegionBindingsConstRef B, const TypedValueRegion *R);
587
  SVal getBindingForArray(RegionBindingsConstRef B, const TypedValueRegion *R);
588
  NonLoc createLazyBinding(RegionBindingsConstRef B, const TypedValueRegion *R);
589
590
  /// Used to lazily generate derived symbols for bindings that are defined
591
  /// implicitly by default bindings in a super region.
592
  ///
593
  /// Note that callers may need to specially handle LazyCompoundVals, which
594
  /// are returned as is in case the caller needs to treat them differently.
595
  Optional<SVal> getBindingForDerivedDefaultValue(RegionBindingsConstRef B,
596
                                                  const MemRegion *superR,
597
                                                  const TypedValueRegion *R,
598
                                                  QualType Ty);
599
600
  /// Get the state and region whose binding this region \p R corresponds to.
601
  ///
602
  /// If there is no lazy binding for \p R, the returned value will have a null
603
  /// \c second. Note that a null pointer can represents a valid Store.
604
  std::pair<Store, const SubRegion *>
605
  findLazyBinding(RegionBindingsConstRef B, const SubRegion *R,
606
                  const SubRegion *originalRegion);
607
608
  /// Returns the cached set of interesting SVals contained within a lazy
609
  /// binding.
610
  ///
611
  /// The precise value of "interesting" is determined for the purposes of
612
  /// RegionStore's internal analysis. It must always contain all regions and
613
  /// symbols, but may omit constants and other kinds of SVal.
614
  const SValListTy &getInterestingValues(nonloc::LazyCompoundVal LCV);
615
616
  //===------------------------------------------------------------------===//
617
  // State pruning.
618
  //===------------------------------------------------------------------===//
619
620
  /// removeDeadBindings - Scans the RegionStore of 'state' for dead values.
621
  ///  It returns a new Store with these values removed.
622
  StoreRef removeDeadBindings(Store store, const StackFrameContext *LCtx,
623
                              SymbolReaper& SymReaper) override;
624
625
  //===------------------------------------------------------------------===//
626
  // Utility methods.
627
  //===------------------------------------------------------------------===//
628
629
11.7M
  RegionBindingsRef getRegionBindings(Store store) const {
630
11.7M
    llvm::PointerIntPair<Store, 1, bool> Ptr;
631
11.7M
    Ptr.setFromOpaqueValue(const_cast<void *>(store));
632
11.7M
    return RegionBindingsRef(
633
11.7M
        CBFactory,
634
11.7M
        static_cast<const RegionBindings::TreeTy *>(Ptr.getPointer()),
635
11.7M
        RBFactory.getTreeFactory(),
636
11.7M
        Ptr.getInt());
637
11.7M
  }
638
639
  void printJson(raw_ostream &Out, Store S, const char *NL = "\n",
640
                 unsigned int Space = 0, bool IsDot = false) const override;
641
642
77.1k
  void iterBindings(Store store, BindingsHandler& f) override {
643
77.1k
    RegionBindingsRef B = getRegionBindings(store);
644
367k
    for (RegionBindingsRef::iterator I = B.begin(), E = B.end(); I != E; 
++I290k
) {
645
291k
      const ClusterBindings &Cluster = I.getData();
646
291k
      for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
647
656k
           CI != CE; 
++CI365k
) {
648
365k
        const BindingKey &K = CI.getKey();
649
365k
        if (!K.isDirect())
650
157k
          continue;
651
208k
        if (const SubRegion *R = dyn_cast<SubRegion>(K.getRegion())) {
652
          // FIXME: Possibly incorporate the offset?
653
208k
          if (!f.HandleBinding(*this, store, R, CI.getData()))
654
544
            return;
655
208k
        }
656
208k
      }
657
291k
    }
658
77.1k
  }
659
};
660
661
} // end anonymous namespace
662
663
//===----------------------------------------------------------------------===//
664
// RegionStore creation.
665
//===----------------------------------------------------------------------===//
666
667
std::unique_ptr<StoreManager>
668
13.6k
ento::CreateRegionStoreManager(ProgramStateManager &StMgr) {
669
13.6k
  RegionStoreFeatures F = maximal_features_tag();
670
13.6k
  return std::make_unique<RegionStoreManager>(StMgr, F);
671
13.6k
}
672
673
std::unique_ptr<StoreManager>
674
0
ento::CreateFieldsOnlyRegionStoreManager(ProgramStateManager &StMgr) {
675
0
  RegionStoreFeatures F = minimal_features_tag();
676
0
  F.enableFields(true);
677
0
  return std::make_unique<RegionStoreManager>(StMgr, F);
678
0
}
679
680
681
//===----------------------------------------------------------------------===//
682
// Region Cluster analysis.
683
//===----------------------------------------------------------------------===//
684
685
namespace {
686
/// Used to determine which global regions are automatically included in the
687
/// initial worklist of a ClusterAnalysis.
688
enum GlobalsFilterKind {
689
  /// Don't include any global regions.
690
  GFK_None,
691
  /// Only include system globals.
692
  GFK_SystemOnly,
693
  /// Include all global regions.
694
  GFK_All
695
};
696
697
template <typename DERIVED>
698
class ClusterAnalysis  {
699
protected:
700
  typedef llvm::DenseMap<const MemRegion *, const ClusterBindings *> ClusterMap;
701
  typedef const MemRegion * WorkListElement;
702
  typedef SmallVector<WorkListElement, 10> WorkList;
703
704
  llvm::SmallPtrSet<const ClusterBindings *, 16> Visited;
705
706
  WorkList WL;
707
708
  RegionStoreManager &RM;
709
  ASTContext &Ctx;
710
  SValBuilder &svalBuilder;
711
712
  RegionBindingsRef B;
713
714
715
protected:
716
4.55M
  const ClusterBindings *getCluster(const MemRegion *R) {
717
4.55M
    return B.lookup(R);
718
4.55M
  }
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::RemoveDeadBindingsWorker>::getCluster(clang::ento::MemRegion const*)
Line
Count
Source
716
4.43M
  const ClusterBindings *getCluster(const MemRegion *R) {
717
4.43M
    return B.lookup(R);
718
4.43M
  }
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::InvalidateRegionsWorker>::getCluster(clang::ento::MemRegion const*)
Line
Count
Source
716
118k
  const ClusterBindings *getCluster(const MemRegion *R) {
717
118k
    return B.lookup(R);
718
118k
  }
719
720
  /// Returns true if all clusters in the given memspace should be initially
721
  /// included in the cluster analysis. Subclasses may provide their
722
  /// own implementation.
723
1.33M
  bool includeEntireMemorySpace(const MemRegion *Base) {
724
1.33M
    return false;
725
1.33M
  }
726
727
public:
728
  ClusterAnalysis(RegionStoreManager &rm, ProgramStateManager &StateMgr,
729
                  RegionBindingsRef b)
730
      : RM(rm), Ctx(StateMgr.getContext()),
731
395k
        svalBuilder(StateMgr.getSValBuilder()), B(std::move(b)) {}
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::RemoveDeadBindingsWorker>::ClusterAnalysis((anonymous namespace)::RegionStoreManager&, clang::ento::ProgramStateManager&, (anonymous namespace)::RegionBindingsRef)
Line
Count
Source
731
361k
        svalBuilder(StateMgr.getSValBuilder()), B(std::move(b)) {}
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::InvalidateRegionsWorker>::ClusterAnalysis((anonymous namespace)::RegionStoreManager&, clang::ento::ProgramStateManager&, (anonymous namespace)::RegionBindingsRef)
Line
Count
Source
731
34.4k
        svalBuilder(StateMgr.getSValBuilder()), B(std::move(b)) {}
732
733
34.4k
  RegionBindingsRef getRegionBindings() const { return B; }
734
735
1.33M
  bool isVisited(const MemRegion *R) {
736
1.33M
    return Visited.count(getCluster(R));
737
1.33M
  }
738
739
395k
  void GenerateClusters() {
740
    // Scan the entire set of bindings and record the region clusters.
741
395k
    for (RegionBindingsRef::iterator RI = B.begin(), RE = B.end();
742
1.84M
         RI != RE; 
++RI1.44M
){
743
1.44M
      const MemRegion *Base = RI.getKey();
744
745
1.44M
      const ClusterBindings &Cluster = RI.getData();
746
1.44M
      assert(!Cluster.isEmpty() && "Empty clusters should be removed");
747
1.44M
      static_cast<DERIVED*>(this)->VisitAddedToCluster(Base, Cluster);
748
749
      // If the base's memspace should be entirely invalidated, add the cluster
750
      // to the workspace up front.
751
1.44M
      if (static_cast<DERIVED*>(this)->includeEntireMemorySpace(Base))
752
48.1k
        AddToWorkList(WorkListElement(Base), &Cluster);
753
1.44M
    }
754
395k
  }
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::RemoveDeadBindingsWorker>::GenerateClusters()
Line
Count
Source
739
361k
  void GenerateClusters() {
740
    // Scan the entire set of bindings and record the region clusters.
741
361k
    for (RegionBindingsRef::iterator RI = B.begin(), RE = B.end();
742
1.69M
         RI != RE; 
++RI1.33M
){
743
1.33M
      const MemRegion *Base = RI.getKey();
744
745
1.33M
      const ClusterBindings &Cluster = RI.getData();
746
1.33M
      assert(!Cluster.isEmpty() && "Empty clusters should be removed");
747
1.33M
      static_cast<DERIVED*>(this)->VisitAddedToCluster(Base, Cluster);
748
749
      // If the base's memspace should be entirely invalidated, add the cluster
750
      // to the workspace up front.
751
1.33M
      if (static_cast<DERIVED*>(this)->includeEntireMemorySpace(Base))
752
0
        AddToWorkList(WorkListElement(Base), &Cluster);
753
1.33M
    }
754
361k
  }
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::InvalidateRegionsWorker>::GenerateClusters()
Line
Count
Source
739
34.4k
  void GenerateClusters() {
740
    // Scan the entire set of bindings and record the region clusters.
741
34.4k
    for (RegionBindingsRef::iterator RI = B.begin(), RE = B.end();
742
147k
         RI != RE; 
++RI113k
){
743
113k
      const MemRegion *Base = RI.getKey();
744
745
113k
      const ClusterBindings &Cluster = RI.getData();
746
113k
      assert(!Cluster.isEmpty() && "Empty clusters should be removed");
747
113k
      static_cast<DERIVED*>(this)->VisitAddedToCluster(Base, Cluster);
748
749
      // If the base's memspace should be entirely invalidated, add the cluster
750
      // to the workspace up front.
751
113k
      if (static_cast<DERIVED*>(this)->includeEntireMemorySpace(Base))
752
48.1k
        AddToWorkList(WorkListElement(Base), &Cluster);
753
113k
    }
754
34.4k
  }
755
756
2.41M
  bool AddToWorkList(WorkListElement E, const ClusterBindings *C) {
757
2.41M
    if (C && 
!Visited.insert(C).second1.70M
)
758
413k
      return false;
759
2.00M
    WL.push_back(E);
760
2.00M
    return true;
761
2.00M
  }
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::RemoveDeadBindingsWorker>::AddToWorkList(clang::ento::MemRegion const*, llvm::ImmutableMap<(anonymous namespace)::BindingKey, clang::ento::SVal, llvm::ImutKeyValueInfo<(anonymous namespace)::BindingKey, clang::ento::SVal> > const*)
Line
Count
Source
756
2.33M
  bool AddToWorkList(WorkListElement E, const ClusterBindings *C) {
757
2.33M
    if (C && 
!Visited.insert(C).second1.63M
)
758
413k
      return false;
759
1.92M
    WL.push_back(E);
760
1.92M
    return true;
761
1.92M
  }
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::InvalidateRegionsWorker>::AddToWorkList(clang::ento::MemRegion const*, llvm::ImmutableMap<(anonymous namespace)::BindingKey, clang::ento::SVal, llvm::ImutKeyValueInfo<(anonymous namespace)::BindingKey, clang::ento::SVal> > const*)
Line
Count
Source
756
83.2k
  bool AddToWorkList(WorkListElement E, const ClusterBindings *C) {
757
83.2k
    if (C && 
!Visited.insert(C).second67.7k
)
758
72
      return false;
759
83.1k
    WL.push_back(E);
760
83.1k
    return true;
761
83.1k
  }
762
763
  bool AddToWorkList(const MemRegion *R) {
764
    return static_cast<DERIVED*>(this)->AddToWorkList(R);
765
  }
766
767
396k
  void RunWorkList() {
768
2.40M
    while (!WL.empty()) {
769
2.00M
      WorkListElement E = WL.pop_back_val();
770
2.00M
      const MemRegion *BaseR = E;
771
772
2.00M
      static_cast<DERIVED*>(this)->VisitCluster(BaseR, getCluster(BaseR));
773
2.00M
    }
774
396k
  }
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::RemoveDeadBindingsWorker>::RunWorkList()
Line
Count
Source
767
362k
  void RunWorkList() {
768
2.28M
    while (!WL.empty()) {
769
1.92M
      WorkListElement E = WL.pop_back_val();
770
1.92M
      const MemRegion *BaseR = E;
771
772
1.92M
      static_cast<DERIVED*>(this)->VisitCluster(BaseR, getCluster(BaseR));
773
1.92M
    }
774
362k
  }
RegionStore.cpp:(anonymous namespace)::ClusterAnalysis<(anonymous namespace)::InvalidateRegionsWorker>::RunWorkList()
Line
Count
Source
767
34.4k
  void RunWorkList() {
768
117k
    while (!WL.empty()) {
769
83.1k
      WorkListElement E = WL.pop_back_val();
770
83.1k
      const MemRegion *BaseR = E;
771
772
83.1k
      static_cast<DERIVED*>(this)->VisitCluster(BaseR, getCluster(BaseR));
773
83.1k
    }
774
34.4k
  }
775
776
113k
  void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C) {}
777
  void VisitCluster(const MemRegion *baseR, const ClusterBindings *C) {}
778
779
  void VisitCluster(const MemRegion *BaseR, const ClusterBindings *C,
780
                    bool Flag) {
781
    static_cast<DERIVED*>(this)->VisitCluster(BaseR, C);
782
  }
783
};
784
}
785
786
//===----------------------------------------------------------------------===//
787
// Binding invalidation.
788
//===----------------------------------------------------------------------===//
789
790
bool RegionStoreManager::scanReachableSymbols(Store S, const MemRegion *R,
791
772k
                                              ScanReachableSymbols &Callbacks) {
792
772k
  assert(R == R->getBaseRegion() && "Should only be called for base regions");
793
772k
  RegionBindingsRef B = getRegionBindings(S);
794
772k
  const ClusterBindings *Cluster = B.lookup(R);
795
796
772k
  if (!Cluster)
797
526k
    return true;
798
799
245k
  for (ClusterBindings::iterator RI = Cluster->begin(), RE = Cluster->end();
800
730k
       RI != RE; 
++RI484k
) {
801
484k
    if (!Callbacks.scan(RI.getData()))
802
0
      return false;
803
484k
  }
804
805
245k
  return true;
806
245k
}
807
808
149
static inline bool isUnionField(const FieldRegion *FR) {
809
149
  return FR->getDecl()->getParent()->isUnion();
810
149
}
811
812
typedef SmallVector<const FieldDecl *, 8> FieldVector;
813
814
154
static void getSymbolicOffsetFields(BindingKey K, FieldVector &Fields) {
815
154
  assert(K.hasSymbolicOffset() && "Not implemented for concrete offset keys");
816
817
154
  const MemRegion *Base = K.getConcreteOffsetRegion();
818
154
  const MemRegion *R = K.getRegion();
819
820
490
  while (R != Base) {
821
336
    if (const FieldRegion *FR = dyn_cast<FieldRegion>(R))
822
149
      if (!isUnionField(FR))
823
133
        Fields.push_back(FR->getDecl());
824
825
336
    R = cast<SubRegion>(R)->getSuperRegion();
826
336
  }
827
154
}
828
829
111
static bool isCompatibleWithFields(BindingKey K, const FieldVector &Fields) {
830
111
  assert(K.hasSymbolicOffset() && "Not implemented for concrete offset keys");
831
832
111
  if (Fields.empty())
833
56
    return true;
834
835
55
  FieldVector FieldsInBindingKey;
836
55
  getSymbolicOffsetFields(K, FieldsInBindingKey);
837
838
55
  ptrdiff_t Delta = FieldsInBindingKey.size() - Fields.size();
839
55
  if (Delta >= 0)
840
51
    return std::equal(FieldsInBindingKey.begin() + Delta,
841
51
                      FieldsInBindingKey.end(),
842
51
                      Fields.begin());
843
4
  else
844
4
    return std::equal(FieldsInBindingKey.begin(), FieldsInBindingKey.end(),
845
4
                      Fields.begin() - Delta);
846
55
}
847
848
/// Collects all bindings in \p Cluster that may refer to bindings within
849
/// \p Top.
850
///
851
/// Each binding is a pair whose \c first is the key (a BindingKey) and whose
852
/// \c second is the value (an SVal).
853
///
854
/// The \p IncludeAllDefaultBindings parameter specifies whether to include
855
/// default bindings that may extend beyond \p Top itself, e.g. if \p Top is
856
/// an aggregate within a larger aggregate with a default binding.
857
static void
858
collectSubRegionBindings(SmallVectorImpl<BindingPair> &Bindings,
859
                         SValBuilder &SVB, const ClusterBindings &Cluster,
860
                         const SubRegion *Top, BindingKey TopKey,
861
23.5k
                         bool IncludeAllDefaultBindings) {
862
23.5k
  FieldVector FieldsInSymbolicSubregions;
863
23.5k
  if (TopKey.hasSymbolicOffset()) {
864
99
    getSymbolicOffsetFields(TopKey, FieldsInSymbolicSubregions);
865
99
    Top = TopKey.getConcreteOffsetRegion();
866
99
    TopKey = BindingKey::Make(Top, BindingKey::Default);
867
99
  }
868
869
  // Find the length (in bits) of the region being invalidated.
870
23.5k
  uint64_t Length = UINT64_MAX;
871
23.5k
  SVal Extent = Top->getMemRegionManager().getStaticSize(Top, SVB);
872
23.5k
  if (Optional<nonloc::ConcreteInt> ExtentCI =
873
23.4k
          Extent.getAs<nonloc::ConcreteInt>()) {
874
23.4k
    const llvm::APSInt &ExtentInt = ExtentCI->getValue();
875
23.4k
    assert(ExtentInt.isNonNegative() || ExtentInt.isUnsigned());
876
    // Extents are in bytes but region offsets are in bits. Be careful!
877
23.4k
    Length = ExtentInt.getLimitedValue() * SVB.getContext().getCharWidth();
878
58
  } else if (const FieldRegion *FR = dyn_cast<FieldRegion>(Top)) {
879
37
    if (FR->getDecl()->isBitField())
880
37
      Length = FR->getDecl()->getBitWidthValue(SVB.getContext());
881
37
  }
882
883
23.5k
  for (ClusterBindings::iterator I = Cluster.begin(), E = Cluster.end();
884
82.1k
       I != E; 
++I58.6k
) {
885
58.6k
    BindingKey NextKey = I.getKey();
886
58.6k
    if (NextKey.getRegion() == TopKey.getRegion()) {
887
      // FIXME: This doesn't catch the case where we're really invalidating a
888
      // region with a symbolic offset. Example:
889
      //      R: points[i].y
890
      //   Next: points[0].x
891
892
58.3k
      if (NextKey.getOffset() > TopKey.getOffset() &&
893
10.7k
          NextKey.getOffset() - TopKey.getOffset() < Length) {
894
        // Case 1: The next binding is inside the region we're invalidating.
895
        // Include it.
896
285
        Bindings.push_back(*I);
897
898
58.0k
      } else if (NextKey.getOffset() == TopKey.getOffset()) {
899
        // Case 2: The next binding is at the same offset as the region we're
900
        // invalidating. In this case, we need to leave default bindings alone,
901
        // since they may be providing a default value for a regions beyond what
902
        // we're invalidating.
903
        // FIXME: This is probably incorrect; consider invalidating an outer
904
        // struct whose first field is bound to a LazyCompoundVal.
905
12.4k
        if (IncludeAllDefaultBindings || 
NextKey.isDirect()11.4k
)
906
12.0k
          Bindings.push_back(*I);
907
12.4k
      }
908
909
249
    } else if (NextKey.hasSymbolicOffset()) {
910
147
      const MemRegion *Base = NextKey.getConcreteOffsetRegion();
911
147
      if (Top->isSubRegionOf(Base) && 
Top != Base111
) {
912
        // Case 3: The next key is symbolic and we just changed something within
913
        // its concrete region. We don't know if the binding is still valid, so
914
        // we'll be conservative and include it.
915
28
        if (IncludeAllDefaultBindings || NextKey.isDirect())
916
28
          if (isCompatibleWithFields(NextKey, FieldsInSymbolicSubregions))
917
28
            Bindings.push_back(*I);
918
119
      } else if (const SubRegion *BaseSR = dyn_cast<SubRegion>(Base)) {
919
        // Case 4: The next key is symbolic, but we changed a known
920
        // super-region. In this case the binding is certainly included.
921
119
        if (BaseSR->isSubRegionOf(Top))
922
83
          if (isCompatibleWithFields(NextKey, FieldsInSymbolicSubregions))
923
41
            Bindings.push_back(*I);
924
119
      }
925
147
    }
926
58.6k
  }
927
23.5k
}
928
929
static void
930
collectSubRegionBindings(SmallVectorImpl<BindingPair> &Bindings,
931
                         SValBuilder &SVB, const ClusterBindings &Cluster,
932
969
                         const SubRegion *Top, bool IncludeAllDefaultBindings) {
933
969
  collectSubRegionBindings(Bindings, SVB, Cluster, Top,
934
969
                           BindingKey::Make(Top, BindingKey::Default),
935
969
                           IncludeAllDefaultBindings);
936
969
}
937
938
RegionBindingsRef
939
RegionStoreManager::removeSubRegionBindings(RegionBindingsConstRef B,
940
176k
                                            const SubRegion *Top) {
941
176k
  BindingKey TopKey = BindingKey::Make(Top, BindingKey::Default);
942
176k
  const MemRegion *ClusterHead = TopKey.getBaseRegion();
943
944
176k
  if (Top == ClusterHead) {
945
    // We can remove an entire cluster's bindings all in one go.
946
117k
    return B.remove(Top);
947
117k
  }
948
949
58.7k
  const ClusterBindings *Cluster = B.lookup(ClusterHead);
950
58.7k
  if (!Cluster) {
951
    // If we're invalidating a region with a symbolic offset, we need to make
952
    // sure we don't treat the base region as uninitialized anymore.
953
36.1k
    if (TopKey.hasSymbolicOffset()) {
954
148
      const SubRegion *Concrete = TopKey.getConcreteOffsetRegion();
955
148
      return B.addBinding(Concrete, BindingKey::Default, UnknownVal());
956
148
    }
957
36.0k
    return B;
958
36.0k
  }
959
960
22.5k
  SmallVector<BindingPair, 32> Bindings;
961
22.5k
  collectSubRegionBindings(Bindings, svalBuilder, *Cluster, Top, TopKey,
962
22.5k
                           /*IncludeAllDefaultBindings=*/false);
963
964
22.5k
  ClusterBindingsRef Result(*Cluster, CBFactory);
965
22.5k
  for (SmallVectorImpl<BindingPair>::const_iterator I = Bindings.begin(),
966
22.5k
                                                    E = Bindings.end();
967
33.7k
       I != E; 
++I11.1k
)
968
11.1k
    Result = Result.remove(I->first);
969
970
  // If we're invalidating a region with a symbolic offset, we need to make sure
971
  // we don't treat the base region as uninitialized anymore.
972
  // FIXME: This isn't very precise; see the example in
973
  // collectSubRegionBindings.
974
22.5k
  if (TopKey.hasSymbolicOffset()) {
975
99
    const SubRegion *Concrete = TopKey.getConcreteOffsetRegion();
976
99
    Result = Result.add(BindingKey::Make(Concrete, BindingKey::Default),
977
99
                        UnknownVal());
978
99
  }
979
980
22.5k
  if (Result.isEmpty())
981
1.34k
    return B.remove(ClusterHead);
982
21.2k
  return B.add(ClusterHead, Result.asImmutableMap());
983
21.2k
}
984
985
namespace {
986
class InvalidateRegionsWorker : public ClusterAnalysis<InvalidateRegionsWorker>
987
{
988
  const Expr *Ex;
989
  unsigned Count;
990
  const LocationContext *LCtx;
991
  InvalidatedSymbols &IS;
992
  RegionAndSymbolInvalidationTraits &ITraits;
993
  StoreManager::InvalidatedRegions *Regions;
994
  GlobalsFilterKind GlobalsFilter;
995
public:
996
  InvalidateRegionsWorker(RegionStoreManager &rm,
997
                          ProgramStateManager &stateMgr,
998
                          RegionBindingsRef b,
999
                          const Expr *ex, unsigned count,
1000
                          const LocationContext *lctx,
1001
                          InvalidatedSymbols &is,
1002
                          RegionAndSymbolInvalidationTraits &ITraitsIn,
1003
                          StoreManager::InvalidatedRegions *r,
1004
                          GlobalsFilterKind GFK)
1005
     : ClusterAnalysis<InvalidateRegionsWorker>(rm, stateMgr, b),
1006
       Ex(ex), Count(count), LCtx(lctx), IS(is), ITraits(ITraitsIn), Regions(r),
1007
34.4k
       GlobalsFilter(GFK) {}
1008
1009
  void VisitCluster(const MemRegion *baseR, const ClusterBindings *C);
1010
  void VisitBinding(SVal V);
1011
1012
  using ClusterAnalysis::AddToWorkList;
1013
1014
  bool AddToWorkList(const MemRegion *R);
1015
1016
  /// Returns true if all clusters in the memory space for \p Base should be
1017
  /// be invalidated.
1018
  bool includeEntireMemorySpace(const MemRegion *Base);
1019
1020
  /// Returns true if the memory space of the given region is one of the global
1021
  /// regions specially included at the start of invalidation.
1022
  bool isInitiallyIncludedGlobalRegion(const MemRegion *R);
1023
};
1024
}
1025
1026
35.1k
bool InvalidateRegionsWorker::AddToWorkList(const MemRegion *R) {
1027
35.1k
  bool doNotInvalidateSuperRegion = ITraits.hasTrait(
1028
35.1k
      R, RegionAndSymbolInvalidationTraits::TK_DoNotInvalidateSuperRegion);
1029
32.9k
  const MemRegion *BaseR = doNotInvalidateSuperRegion ? 
R2.21k
: R->getBaseRegion();
1030
35.1k
  return AddToWorkList(WorkListElement(BaseR), getCluster(BaseR));
1031
35.1k
}
1032
1033
71.9k
void InvalidateRegionsWorker::VisitBinding(SVal V) {
1034
  // A symbol?  Mark it touched by the invalidation.
1035
71.9k
  if (SymbolRef Sym = V.getAsSymbol())
1036
66.1k
    IS.insert(Sym);
1037
1038
71.9k
  if (const MemRegion *R = V.getAsRegion()) {
1039
1.11k
    AddToWorkList(R);
1040
1.11k
    return;
1041
1.11k
  }
1042
1043
  // Is it a LazyCompoundVal?  All references get invalidated as well.
1044
70.7k
  if (Optional<nonloc::LazyCompoundVal> LCS =
1045
143
          V.getAs<nonloc::LazyCompoundVal>()) {
1046
1047
143
    const RegionStoreManager::SValListTy &Vals = RM.getInterestingValues(*LCS);
1048
1049
143
    for (RegionStoreManager::SValListTy::const_iterator I = Vals.begin(),
1050
143
                                                        E = Vals.end();
1051
155
         I != E; 
++I12
)
1052
12
      VisitBinding(*I);
1053
1054
143
    return;
1055
143
  }
1056
70.7k
}
1057
1058
void InvalidateRegionsWorker::VisitCluster(const MemRegion *baseR,
1059
83.1k
                                           const ClusterBindings *C) {
1060
1061
83.1k
  bool PreserveRegionsContents =
1062
83.1k
      ITraits.hasTrait(baseR,
1063
83.1k
                       RegionAndSymbolInvalidationTraits::TK_PreserveContents);
1064
1065
83.1k
  if (C) {
1066
140k
    for (ClusterBindings::iterator I = C->begin(), E = C->end(); I != E; 
++I71.8k
)
1067
71.8k
      VisitBinding(I.getData());
1068
1069
    // Invalidate regions contents.
1070
68.1k
    if (!PreserveRegionsContents)
1071
64.6k
      B = B.remove(baseR);
1072
68.1k
  }
1073
1074
83.1k
  if (const auto *TO = dyn_cast<TypedValueRegion>(baseR)) {
1075
25.2k
    if (const auto *RD = TO->getValueType()->getAsCXXRecordDecl()) {
1076
1077
      // Lambdas can affect all static local variables without explicitly
1078
      // capturing those.
1079
      // We invalidate all static locals referenced inside the lambda body.
1080
18.8k
      if (RD->isLambda() && 
RD->getLambdaCallOperator()->getBody()4
) {
1081
4
        using namespace ast_matchers;
1082
1083
4
        const char *DeclBind = "DeclBind";
1084
4
        StatementMatcher RefToStatic = stmt(hasDescendant(declRefExpr(
1085
4
              to(varDecl(hasStaticStorageDuration()).bind(DeclBind)))));
1086
4
        auto Matches =
1087
4
            match(RefToStatic, *RD->getLambdaCallOperator()->getBody(),
1088
4
                  RD->getASTContext());
1089
1090
2
        for (BoundNodes &Match : Matches) {
1091
2
          auto *VD = Match.getNodeAs<VarDecl>(DeclBind);
1092
2
          const VarRegion *ToInvalidate =
1093
2
              RM.getRegionManager().getVarRegion(VD, LCtx);
1094
2
          AddToWorkList(ToInvalidate);
1095
2
        }
1096
4
      }
1097
18.8k
    }
1098
25.2k
  }
1099
1100
  // BlockDataRegion?  If so, invalidate captured variables that are passed
1101
  // by reference.
1102
83.1k
  if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(baseR)) {
1103
138
    for (BlockDataRegion::referenced_vars_iterator
1104
138
         BI = BR->referenced_vars_begin(), BE = BR->referenced_vars_end() ;
1105
268
         BI != BE; 
++BI130
) {
1106
130
      const VarRegion *VR = BI.getCapturedRegion();
1107
130
      const VarDecl *VD = VR->getDecl();
1108
130
      if (VD->hasAttr<BlocksAttr>() || 
!VD->hasLocalStorage()114
) {
1109
32
        AddToWorkList(VR);
1110
32
      }
1111
98
      else if (Loc::isLocType(VR->getValueType())) {
1112
        // Map the current bindings to a Store to retrieve the value
1113
        // of the binding.  If that binding itself is a region, we should
1114
        // invalidate that region.  This is because a block may capture
1115
        // a pointer value, but the thing pointed by that pointer may
1116
        // get invalidated.
1117
59
        SVal V = RM.getBinding(B, loc::MemRegionVal(VR));
1118
59
        if (Optional<Loc> L = V.getAs<Loc>()) {
1119
59
          if (const MemRegion *LR = L->getAsRegion())
1120
59
            AddToWorkList(LR);
1121
59
        }
1122
59
      }
1123
130
    }
1124
138
    return;
1125
138
  }
1126
1127
  // Symbolic region?
1128
83.0k
  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(baseR))
1129
9.80k
    IS.insert(SR->getSymbol());
1130
1131
  // Nothing else should be done in the case when we preserve regions context.
1132
83.0k
  if (PreserveRegionsContents)
1133
7.47k
    return;
1134
1135
  // Otherwise, we have a normal data region. Record that we touched the region.
1136
75.5k
  if (Regions)
1137
75.5k
    Regions->push_back(baseR);
1138
1139
75.5k
  if (isa<AllocaRegion>(baseR) || 
isa<SymbolicRegion>(baseR)75.5k
) {
1140
    // Invalidate the region by setting its default value to
1141
    // conjured symbol. The type of the symbol is irrelevant.
1142
7.76k
    DefinedOrUnknownSVal V =
1143
7.76k
      svalBuilder.conjureSymbolVal(baseR, Ex, LCtx, Ctx.IntTy, Count);
1144
7.76k
    B = B.addBinding(baseR, BindingKey::Default, V);
1145
7.76k
    return;
1146
7.76k
  }
1147
1148
67.7k
  if (!baseR->isBoundable())
1149
48.3k
    return;
1150
1151
19.4k
  const TypedValueRegion *TR = cast<TypedValueRegion>(baseR);
1152
19.4k
  QualType T = TR->getValueType();
1153
1154
19.4k
  if (isInitiallyIncludedGlobalRegion(baseR)) {
1155
    // If the region is a global and we are invalidating all globals,
1156
    // erasing the entry is good enough.  This causes all globals to be lazily
1157
    // symbolicated from the same base symbol.
1158
403
    return;
1159
403
  }
1160
1161
19.0k
  if (T->isRecordType()) {
1162
    // Invalidate the region by setting its default value to
1163
    // conjured symbol. The type of the symbol is irrelevant.
1164
16.9k
    DefinedOrUnknownSVal V = svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1165
16.9k
                                                          Ctx.IntTy, Count);
1166
16.9k
    B = B.addBinding(baseR, BindingKey::Default, V);
1167
16.9k
    return;
1168
16.9k
  }
1169
1170
2.13k
  if (const ArrayType *AT = Ctx.getAsArrayType(T)) {
1171
786
    bool doNotInvalidateSuperRegion = ITraits.hasTrait(
1172
786
        baseR,
1173
786
        RegionAndSymbolInvalidationTraits::TK_DoNotInvalidateSuperRegion);
1174
1175
786
    if (doNotInvalidateSuperRegion) {
1176
      // We are not doing blank invalidation of the whole array region so we
1177
      // have to manually invalidate each elements.
1178
35
      Optional<uint64_t> NumElements;
1179
1180
      // Compute lower and upper offsets for region within array.
1181
35
      if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT))
1182
35
        NumElements = CAT->getSize().getZExtValue();
1183
35
      if (!NumElements) // We are not dealing with a constant size array
1184
0
        goto conjure_default;
1185
35
      QualType ElementTy = AT->getElementType();
1186
35
      uint64_t ElemSize = Ctx.getTypeSize(ElementTy);
1187
35
      const RegionOffset &RO = baseR->getAsOffset();
1188
35
      const MemRegion *SuperR = baseR->getBaseRegion();
1189
35
      if (RO.hasSymbolicOffset()) {
1190
        // If base region has a symbolic offset,
1191
        // we revert to invalidating the super region.
1192
4
        if (SuperR)
1193
4
          AddToWorkList(SuperR);
1194
4
        goto conjure_default;
1195
4
      }
1196
1197
31
      uint64_t LowerOffset = RO.getOffset();
1198
31
      uint64_t UpperOffset = LowerOffset + *NumElements * ElemSize;
1199
31
      bool UpperOverflow = UpperOffset < LowerOffset;
1200
1201
      // Invalidate regions which are within array boundaries,
1202
      // or have a symbolic offset.
1203
31
      if (!SuperR)
1204
0
        goto conjure_default;
1205
1206
31
      const ClusterBindings *C = B.lookup(SuperR);
1207
31
      if (!C)
1208
0
        goto conjure_default;
1209
1210
159
      
for (ClusterBindings::iterator I = C->begin(), E = C->end(); 31
I != E;
1211
128
           ++I) {
1212
128
        const BindingKey &BK = I.getKey();
1213
128
        Optional<uint64_t> ROffset =
1214
123
            BK.hasSymbolicOffset() ? 
Optional<uint64_t>()5
: BK.getOffset();
1215
1216
        // Check offset is not symbolic and within array's boundaries.
1217
        // Handles arrays of 0 elements and of 0-sized elements as well.
1218
128
        if (!ROffset ||
1219
123
            ((*ROffset >= LowerOffset && 
*ROffset < UpperOffset110
) ||
1220
50
             (UpperOverflow &&
1221
11
              (*ROffset >= LowerOffset || 
*ROffset < UpperOffset5
)) ||
1222
89
             
(42
LowerOffset == UpperOffset42
&&
*ROffset == LowerOffset3
))) {
1223
89
          B = B.removeBinding(I.getKey());
1224
          // Bound symbolic regions need to be invalidated for dead symbol
1225
          // detection.
1226
89
          SVal V = I.getData();
1227
89
          const MemRegion *R = V.getAsRegion();
1228
89
          if (R && 
isa<SymbolicRegion>(R)3
)
1229
3
            VisitBinding(V);
1230
89
        }
1231
128
      }
1232
31
    }
1233
786
  conjure_default:
1234
      // Set the default value of the array to conjured symbol.
1235
786
    DefinedOrUnknownSVal V =
1236
786
    svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1237
786
                                     AT->getElementType(), Count);
1238
786
    B = B.addBinding(baseR, BindingKey::Default, V);
1239
786
    return;
1240
1.34k
  }
1241
1242
1.34k
  DefinedOrUnknownSVal V = svalBuilder.conjureSymbolVal(baseR, Ex, LCtx,
1243
1.34k
                                                        T,Count);
1244
1.34k
  assert(SymbolManager::canSymbolicate(T) || V.isUnknown());
1245
1.34k
  B = B.addBinding(baseR, BindingKey::Direct, V);
1246
1.34k
}
1247
1248
bool InvalidateRegionsWorker::isInitiallyIncludedGlobalRegion(
1249
132k
    const MemRegion *R) {
1250
132k
  switch (GlobalsFilter) {
1251
2.78k
  case GFK_None:
1252
2.78k
    return false;
1253
21.6k
  case GFK_SystemOnly:
1254
21.6k
    return isa<GlobalSystemSpaceRegion>(R->getMemorySpace());
1255
108k
  case GFK_All:
1256
108k
    return isa<NonStaticGlobalSpaceRegion>(R->getMemorySpace());
1257
0
  }
1258
1259
0
  llvm_unreachable("unknown globals filter");
1260
0
}
1261
1262
113k
bool InvalidateRegionsWorker::includeEntireMemorySpace(const MemRegion *Base) {
1263
113k
  if (isInitiallyIncludedGlobalRegion(Base))
1264
48.0k
    return true;
1265
1266
65.4k
  const MemSpaceRegion *MemSpace = Base->getMemorySpace();
1267
65.4k
  return ITraits.hasTrait(MemSpace,
1268
65.4k
                          RegionAndSymbolInvalidationTraits::TK_EntireMemSpace);
1269
65.4k
}
1270
1271
RegionBindingsRef
1272
RegionStoreManager::invalidateGlobalRegion(MemRegion::Kind K,
1273
                                           const Expr *Ex,
1274
                                           unsigned Count,
1275
                                           const LocationContext *LCtx,
1276
                                           RegionBindingsRef B,
1277
60.5k
                                           InvalidatedRegions *Invalidated) {
1278
  // Bind the globals memory space to a new symbol that we will use to derive
1279
  // the bindings for all globals.
1280
60.5k
  const GlobalsSpaceRegion *GS = MRMgr.getGlobalsRegion(K);
1281
60.5k
  SVal V = svalBuilder.conjureSymbolVal(/* symbolTag = */ (const void*) GS, Ex, LCtx,
1282
60.5k
                                        /* type does not matter */ Ctx.IntTy,
1283
60.5k
                                        Count);
1284
1285
60.5k
  B = B.removeBinding(GS)
1286
60.5k
       .addBinding(BindingKey::Make(GS, BindingKey::Default), V);
1287
1288
  // Even if there are no bindings in the global scope, we still need to
1289
  // record that we touched it.
1290
60.5k
  if (Invalidated)
1291
60.5k
    Invalidated->push_back(GS);
1292
1293
60.5k
  return B;
1294
60.5k
}
1295
1296
void RegionStoreManager::populateWorkList(InvalidateRegionsWorker &W,
1297
                                          ArrayRef<SVal> Values,
1298
34.4k
                                          InvalidatedRegions *TopLevelRegions) {
1299
34.4k
  for (ArrayRef<SVal>::iterator I = Values.begin(),
1300
84.6k
                                E = Values.end(); I != E; 
++I50.1k
) {
1301
50.1k
    SVal V = *I;
1302
50.1k
    if (Optional<nonloc::LazyCompoundVal> LCS =
1303
9.65k
        V.getAs<nonloc::LazyCompoundVal>()) {
1304
1305
9.65k
      const SValListTy &Vals = getInterestingValues(*LCS);
1306
1307
9.65k
      for (SValListTy::const_iterator I = Vals.begin(),
1308
19.2k
                                      E = Vals.end(); I != E; 
++I9.58k
) {
1309
        // Note: the last argument is false here because these are
1310
        // non-top-level regions.
1311
9.58k
        if (const MemRegion *R = (*I).getAsRegion())
1312
438
          W.AddToWorkList(R);
1313
9.58k
      }
1314
9.65k
      continue;
1315
9.65k
    }
1316
1317
40.5k
    if (const MemRegion *R = V.getAsRegion()) {
1318
33.4k
      if (TopLevelRegions)
1319
33.4k
        TopLevelRegions->push_back(R);
1320
33.4k
      W.AddToWorkList(R);
1321
33.4k
      continue;
1322
33.4k
    }
1323
40.5k
  }
1324
34.4k
}
1325
1326
StoreRef
1327
RegionStoreManager::invalidateRegions(Store store,
1328
                                     ArrayRef<SVal> Values,
1329
                                     const Expr *Ex, unsigned Count,
1330
                                     const LocationContext *LCtx,
1331
                                     const CallEvent *Call,
1332
                                     InvalidatedSymbols &IS,
1333
                                     RegionAndSymbolInvalidationTraits &ITraits,
1334
                                     InvalidatedRegions *TopLevelRegions,
1335
34.4k
                                     InvalidatedRegions *Invalidated) {
1336
34.4k
  GlobalsFilterKind GlobalsFilter;
1337
34.4k
  if (Call) {
1338
33.4k
    if (Call->isInSystemHeader())
1339
6.43k
      GlobalsFilter = GFK_SystemOnly;
1340
27.0k
    else
1341
27.0k
      GlobalsFilter = GFK_All;
1342
958
  } else {
1343
958
    GlobalsFilter = GFK_None;
1344
958
  }
1345
1346
34.4k
  RegionBindingsRef B = getRegionBindings(store);
1347
34.4k
  InvalidateRegionsWorker W(*this, StateMgr, B, Ex, Count, LCtx, IS, ITraits,
1348
34.4k
                            Invalidated, GlobalsFilter);
1349
1350
  // Scan the bindings and generate the clusters.
1351
34.4k
  W.GenerateClusters();
1352
1353
  // Add the regions to the worklist.
1354
34.4k
  populateWorkList(W, Values, TopLevelRegions);
1355
1356
34.4k
  W.RunWorkList();
1357
1358
  // Return the new bindings.
1359
34.4k
  B = W.getRegionBindings();
1360
1361
  // For calls, determine which global regions should be invalidated and
1362
  // invalidate them. (Note that function-static and immutable globals are never
1363
  // invalidated by this.)
1364
  // TODO: This could possibly be more precise with modules.
1365
34.4k
  switch (GlobalsFilter) {
1366
27.0k
  case GFK_All:
1367
27.0k
    B = invalidateGlobalRegion(MemRegion::GlobalInternalSpaceRegionKind,
1368
27.0k
                               Ex, Count, LCtx, B, Invalidated);
1369
27.0k
    LLVM_FALLTHROUGH;
1370
33.4k
  case GFK_SystemOnly:
1371
33.4k
    B = invalidateGlobalRegion(MemRegion::GlobalSystemSpaceRegionKind,
1372
33.4k
                               Ex, Count, LCtx, B, Invalidated);
1373
33.4k
    LLVM_FALLTHROUGH;
1374
34.4k
  case GFK_None:
1375
34.4k
    break;
1376
34.4k
  }
1377
1378
34.4k
  return StoreRef(B.asStore(), *this);
1379
34.4k
}
1380
1381
//===----------------------------------------------------------------------===//
1382
// Location and region casting.
1383
//===----------------------------------------------------------------------===//
1384
1385
/// ArrayToPointer - Emulates the "decay" of an array to a pointer
1386
///  type.  'Array' represents the lvalue of the array being decayed
1387
///  to a pointer, and the returned SVal represents the decayed
1388
///  version of that lvalue (i.e., a pointer to the first element of
1389
///  the array).  This is called by ExprEngine when evaluating casts
1390
///  from arrays to pointers.
1391
9.31k
SVal RegionStoreManager::ArrayToPointer(Loc Array, QualType T) {
1392
9.31k
  if (Array.getAs<loc::ConcreteInt>())
1393
7
    return Array;
1394
1395
9.30k
  if (!Array.getAs<loc::MemRegionVal>())
1396
0
    return UnknownVal();
1397
1398
9.30k
  const SubRegion *R =
1399
9.30k
      cast<SubRegion>(Array.castAs<loc::MemRegionVal>().getRegion());
1400
9.30k
  NonLoc ZeroIdx = svalBuilder.makeZeroArrayIndex();
1401
9.30k
  return loc::MemRegionVal(MRMgr.getElementRegion(T, ZeroIdx, R, Ctx));
1402
9.30k
}
1403
1404
//===----------------------------------------------------------------------===//
1405
// Loading values from regions.
1406
//===----------------------------------------------------------------------===//
1407
1408
514k
SVal RegionStoreManager::getBinding(RegionBindingsConstRef B, Loc L, QualType T) {
1409
514k
  assert(!L.getAs<UnknownVal>() && "location unknown");
1410
514k
  assert(!L.getAs<UndefinedVal>() && "location undefined");
1411
1412
  // For access to concrete addresses, return UnknownVal.  Checks
1413
  // for null dereferences (and similar errors) are done by checkers, not
1414
  // the Store.
1415
  // FIXME: We can consider lazily symbolicating such memory, but we really
1416
  // should defer this when we can reason easily about symbolicating arrays
1417
  // of bytes.
1418
514k
  if (L.getAs<loc::ConcreteInt>()) {
1419
12
    return UnknownVal();
1420
12
  }
1421
514k
  if (!L.getAs<loc::MemRegionVal>()) {
1422
0
    return UnknownVal();
1423
0
  }
1424
1425
514k
  const MemRegion *MR = L.castAs<loc::MemRegionVal>().getRegion();
1426
1427
514k
  if (isa<BlockDataRegion>(MR)) {
1428
1
    return UnknownVal();
1429
1
  }
1430
1431
514k
  if (!isa<TypedValueRegion>(MR)) {
1432
7.13k
    if (T.isNull()) {
1433
5.16k
      if (const TypedRegion *TR = dyn_cast<TypedRegion>(MR))
1434
0
        T = TR->getLocationType()->getPointeeType();
1435
5.16k
      else if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(MR))
1436
5.16k
        T = SR->getSymbol()->getType()->getPointeeType();
1437
5.16k
    }
1438
7.13k
    assert(!T.isNull() && "Unable to auto-detect binding type!");
1439
7.13k
    assert(!T->isVoidType() && "Attempting to dereference a void pointer!");
1440
7.13k
    MR = GetElementZeroRegion(cast<SubRegion>(MR), T);
1441
507k
  } else {
1442
507k
    T = cast<TypedValueRegion>(MR)->getValueType();
1443
507k
  }
1444
1445
  // FIXME: Perhaps this method should just take a 'const MemRegion*' argument
1446
  //  instead of 'Loc', and have the other Loc cases handled at a higher level.
1447
514k
  const TypedValueRegion *R = cast<TypedValueRegion>(MR);
1448
514k
  QualType RTy = R->getValueType();
1449
1450
  // FIXME: we do not yet model the parts of a complex type, so treat the
1451
  // whole thing as "unknown".
1452
514k
  if (RTy->isAnyComplexType())
1453
87
    return UnknownVal();
1454
1455
  // FIXME: We should eventually handle funny addressing.  e.g.:
1456
  //
1457
  //   int x = ...;
1458
  //   int *p = &x;
1459
  //   char *q = (char*) p;
1460
  //   char c = *q;  // returns the first byte of 'x'.
1461
  //
1462
  // Such funny addressing will occur due to layering of regions.
1463
514k
  if (RTy->isStructureOrClassType())
1464
58.3k
    return getBindingForStruct(B, R);
1465
1466
  // FIXME: Handle unions.
1467
456k
  if (RTy->isUnionType())
1468
85
    return createLazyBinding(B, R);
1469
1470
455k
  if (RTy->isArrayType()) {
1471
2.03k
    if (RTy->isConstantArrayType())
1472
2.03k
      return getBindingForArray(B, R);
1473
2
    else
1474
2
      return UnknownVal();
1475
453k
  }
1476
1477
  // FIXME: handle Vector types.
1478
453k
  if (RTy->isVectorType())
1479
21
    return UnknownVal();
1480
1481
453k
  if (const FieldRegion* FR = dyn_cast<FieldRegion>(R))
1482
69.0k
    return CastRetrievedVal(getBindingForField(B, FR), FR, T);
1483
1484
384k
  if (const ElementRegion* ER = dyn_cast<ElementRegion>(R)) {
1485
    // FIXME: Here we actually perform an implicit conversion from the loaded
1486
    // value to the element type.  Eventually we want to compose these values
1487
    // more intelligently.  For example, an 'element' can encompass multiple
1488
    // bound regions (e.g., several bound bytes), or could be a subset of
1489
    // a larger value.
1490
16.5k
    return CastRetrievedVal(getBindingForElement(B, ER), ER, T);
1491
16.5k
  }
1492
1493
368k
  if (const ObjCIvarRegion *IVR = dyn_cast<ObjCIvarRegion>(R)) {
1494
    // FIXME: Here we actually perform an implicit conversion from the loaded
1495
    // value to the ivar type.  What we should model is stores to ivars
1496
    // that blow past the extent of the ivar.  If the address of the ivar is
1497
    // reinterpretted, it is possible we stored a different value that could
1498
    // fit within the ivar.  Either we need to cast these when storing them
1499
    // or reinterpret them lazily (as we do here).
1500
2.51k
    return CastRetrievedVal(getBindingForObjCIvar(B, IVR), IVR, T);
1501
2.51k
  }
1502
1503
365k
  if (const VarRegion *VR = dyn_cast<VarRegion>(R)) {
1504
    // FIXME: Here we actually perform an implicit conversion from the loaded
1505
    // value to the variable type.  What we should model is stores to variables
1506
    // that blow past the extent of the variable.  If the address of the
1507
    // variable is reinterpretted, it is possible we stored a different value
1508
    // that could fit within the variable.  Either we need to cast these when
1509
    // storing them or reinterpret them lazily (as we do here).
1510
304k
    return CastRetrievedVal(getBindingForVar(B, VR), VR, T);
1511
304k
  }
1512
1513
61.1k
  const SVal *V = B.lookup(R, BindingKey::Direct);
1514
1515
  // Check if the region has a binding.
1516
61.1k
  if (V)
1517
57.4k
    return *V;
1518
1519
  // The location does not have a bound value.  This means that it has
1520
  // the value it had upon its creation and/or entry to the analyzed
1521
  // function/method.  These are either symbolic values or 'undefined'.
1522
3.68k
  if (R->hasStackNonParametersStorage()) {
1523
    // All stack variables are considered to have undefined values
1524
    // upon creation.  All heap allocated blocks are considered to
1525
    // have undefined values as well unless they are explicitly bound
1526
    // to specific values.
1527
42
    return UndefinedVal();
1528
42
  }
1529
1530
  // All other values are symbolic.
1531
3.64k
  return svalBuilder.getRegionValueSymbolVal(R);
1532
3.64k
}
1533
1534
814
static QualType getUnderlyingType(const SubRegion *R) {
1535
814
  QualType RegionTy;
1536
814
  if (const TypedValueRegion *TVR = dyn_cast<TypedValueRegion>(R))
1537
807
    RegionTy = TVR->getValueType();
1538
1539
814
  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R))
1540
7
    RegionTy = SR->getSymbol()->getType();
1541
1542
814
  return RegionTy;
1543
814
}
1544
1545
/// Checks to see if store \p B has a lazy binding for region \p R.
1546
///
1547
/// If \p AllowSubregionBindings is \c false, a lazy binding will be rejected
1548
/// if there are additional bindings within \p R.
1549
///
1550
/// Note that unlike RegionStoreManager::findLazyBinding, this will not search
1551
/// for lazy bindings for super-regions of \p R.
1552
static Optional<nonloc::LazyCompoundVal>
1553
getExistingLazyBinding(SValBuilder &SVB, RegionBindingsConstRef B,
1554
168k
                       const SubRegion *R, bool AllowSubregionBindings) {
1555
168k
  Optional<SVal> V = B.getDefaultBinding(R);
1556
168k
  if (!V)
1557
149k
    return None;
1558
1559
19.0k
  Optional<nonloc::LazyCompoundVal> LCV = V->getAs<nonloc::LazyCompoundVal>();
1560
19.0k
  if (!LCV)
1561
18.2k
    return None;
1562
1563
  // If the LCV is for a subregion, the types might not match, and we shouldn't
1564
  // reuse the binding.
1565
814
  QualType RegionTy = getUnderlyingType(R);
1566
814
  if (!RegionTy.isNull() &&
1567
814
      !RegionTy->isVoidPointerType()) {
1568
810
    QualType SourceRegionTy = LCV->getRegion()->getValueType();
1569
810
    if (!SVB.getContext().hasSameUnqualifiedType(RegionTy, SourceRegionTy))
1570
222
      return None;
1571
592
  }
1572
1573
592
  if (!AllowSubregionBindings) {
1574
    // If there are any other bindings within this region, we shouldn't reuse
1575
    // the top-level binding.
1576
148
    SmallVector<BindingPair, 16> Bindings;
1577
148
    collectSubRegionBindings(Bindings, SVB, *B.lookup(R->getBaseRegion()), R,
1578
148
                             /*IncludeAllDefaultBindings=*/true);
1579
148
    if (Bindings.size() > 1)
1580
2
      return None;
1581
590
  }
1582
1583
590
  return *LCV;
1584
590
}
1585
1586
1587
std::pair<Store, const SubRegion *>
1588
RegionStoreManager::findLazyBinding(RegionBindingsConstRef B,
1589
                                   const SubRegion *R,
1590
186k
                                   const SubRegion *originalRegion) {
1591
186k
  if (originalRegion != R) {
1592
114k
    if (Optional<nonloc::LazyCompoundVal> V =
1593
444
          getExistingLazyBinding(svalBuilder, B, R, true))
1594
444
      return std::make_pair(V->getStore(), V->getRegion());
1595
186k
  }
1596
1597
186k
  typedef std::pair<Store, const SubRegion *> StoreRegionPair;
1598
186k
  StoreRegionPair Result = StoreRegionPair();
1599
1600
186k
  if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
1601
48.4k
    Result = findLazyBinding(B, cast<SubRegion>(ER->getSuperRegion()),
1602
48.4k
                             originalRegion);
1603
1604
48.4k
    if (Result.second)
1605
254
      Result.second = MRMgr.getElementRegionWithSuper(ER, Result.second);
1606
1607
137k
  } else if (const FieldRegion *FR = dyn_cast<FieldRegion>(R)) {
1608
65.0k
    Result = findLazyBinding(B, cast<SubRegion>(FR->getSuperRegion()),
1609
65.0k
                                       originalRegion);
1610
1611
65.0k
    if (Result.second)
1612
449
      Result.second = MRMgr.getFieldRegionWithSuper(FR, Result.second);
1613
1614
72.5k
  } else if (const CXXBaseObjectRegion *BaseReg =
1615
1.09k
               dyn_cast<CXXBaseObjectRegion>(R)) {
1616
    // C++ base object region is another kind of region that we should blast
1617
    // through to look for lazy compound value. It is like a field region.
1618
1.09k
    Result = findLazyBinding(B, cast<SubRegion>(BaseReg->getSuperRegion()),
1619
1.09k
                             originalRegion);
1620
1621
1.09k
    if (Result.second)
1622
40
      Result.second = MRMgr.getCXXBaseObjectRegionWithSuper(BaseReg,
1623
40
                                                            Result.second);
1624
1.09k
  }
1625
1626
186k
  return Result;
1627
186k
}
1628
1629
SVal RegionStoreManager::getBindingForElement(RegionBindingsConstRef B,
1630
16.6k
                                              const ElementRegion* R) {
1631
  // Check if the region has a binding.
1632
16.6k
  if (const Optional<SVal> &V = B.getDirectBinding(R))
1633
3.67k
    return *V;
1634
1635
12.9k
  const MemRegion* superR = R->getSuperRegion();
1636
1637
  // Check if the region is an element region of a string literal.
1638
12.9k
  if (const StringRegion *StrR = dyn_cast<StringRegion>(superR)) {
1639
    // FIXME: Handle loads from strings where the literal is treated as
1640
    // an integer, e.g., *((unsigned int*)"hello")
1641
192
    QualType T = Ctx.getAsArrayType(StrR->getValueType())->getElementType();
1642
192
    if (!Ctx.hasSameUnqualifiedType(T, R->getElementType()))
1643
2
      return UnknownVal();
1644
1645
190
    const StringLiteral *Str = StrR->getStringLiteral();
1646
190
    SVal Idx = R->getIndex();
1647
190
    if (Optional<nonloc::ConcreteInt> CI = Idx.getAs<nonloc::ConcreteInt>()) {
1648
190
      int64_t i = CI->getValue().getSExtValue();
1649
      // Abort on string underrun.  This can be possible by arbitrary
1650
      // clients of getBindingForElement().
1651
190
      if (i < 0)
1652
0
        return UndefinedVal();
1653
190
      int64_t length = Str->getLength();
1654
      // Technically, only i == length is guaranteed to be null.
1655
      // However, such overflows should be caught before reaching this point;
1656
      // the only time such an access would be made is if a string literal was
1657
      // used to initialize a larger array.
1658
182
      char c = (i >= length) ? 
'\0'8
: Str->getCodeUnit(i);
1659
190
      return svalBuilder.makeIntVal(c, T);
1660
190
    }
1661
12.8k
  } else if (const VarRegion *VR = dyn_cast<VarRegion>(superR)) {
1662
    // Check if the containing array has an initialized value that we can trust.
1663
    // We can trust a const value or a value of a global initializer in main().
1664
3.42k
    const VarDecl *VD = VR->getDecl();
1665
3.42k
    if (VD->getType().isConstQualified() ||
1666
3.37k
        R->getElementType().isConstQualified() ||
1667
3.37k
        (B.isMainAnalysis() && 
VD->hasGlobalStorage()7
)) {
1668
57
      if (const Expr *Init = VD->getAnyInitializer()) {
1669
57
        if (const auto *InitList = dyn_cast<InitListExpr>(Init)) {
1670
          // The array index has to be known.
1671
57
          if (auto CI = R->getIndex().getAs<nonloc::ConcreteInt>()) {
1672
57
            int64_t i = CI->getValue().getSExtValue();
1673
            // If it is known that the index is out of bounds, we can return
1674
            // an undefined value.
1675
57
            if (i < 0)
1676
1
              return UndefinedVal();
1677
1678
56
            if (auto CAT = Ctx.getAsConstantArrayType(VD->getType()))
1679
56
              if (CAT->getSize().sle(i))
1680
1
                return UndefinedVal();
1681
1682
            // If there is a list, but no init, it must be zero.
1683
55
            if (i >= InitList->getNumInits())
1684
1
              return svalBuilder.makeZeroVal(R->getElementType());
1685
1686
54
            if (const Expr *ElemInit = InitList->getInit(i))
1687
54
              if (Optional<SVal> V = svalBuilder.getConstantVal(ElemInit))
1688
54
                return *V;
1689
12.7k
          }
1690
57
        }
1691
57
      }
1692
57
    }
1693
3.42k
  }
1694
1695
  // Check for loads from a code text region.  For such loads, just give up.
1696
12.7k
  if (isa<CodeTextRegion>(superR))
1697
89
    return UnknownVal();
1698
1699
  // Handle the case where we are indexing into a larger scalar object.
1700
  // For example, this handles:
1701
  //   int x = ...
1702
  //   char *y = &x;
1703
  //   return *y;
1704
  // FIXME: This is a hack, and doesn't do anything really intelligent yet.
1705
12.6k
  const RegionRawOffset &O = R->getAsArrayOffset();
1706
1707
  // If we cannot reason about the offset, return an unknown value.
1708
12.6k
  if (!O.getRegion())
1709
1.93k
    return UnknownVal();
1710
1711
10.7k
  if (const TypedValueRegion *baseR =
1712
4.35k
        dyn_cast_or_null<TypedValueRegion>(O.getRegion())) {
1713
4.35k
    QualType baseT = baseR->getValueType();
1714
4.35k
    if (baseT->isScalarType()) {
1715
80
      QualType elemT = R->getElementType();
1716
80
      if (elemT->isScalarType()) {
1717
80
        if (Ctx.getTypeSizeInChars(baseT) >= Ctx.getTypeSizeInChars(elemT)) {
1718
79
          if (const Optional<SVal> &V = B.getDirectBinding(superR)) {
1719
4
            if (SymbolRef parentSym = V->getAsSymbol())
1720
0
              return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1721
1722
4
            if (V->isUnknownOrUndef())
1723
0
              return *V;
1724
            // Other cases: give up.  We are indexing into a larger object
1725
            // that has some value, but we don't know how to handle that yet.
1726
4
            return UnknownVal();
1727
4
          }
1728
79
        }
1729
80
      }
1730
80
    }
1731
4.35k
  }
1732
10.7k
  return getBindingForFieldOrElementCommon(B, R, R->getElementType());
1733
10.7k
}
1734
1735
SVal RegionStoreManager::getBindingForField(RegionBindingsConstRef B,
1736
91.3k
                                            const FieldRegion* R) {
1737
1738
  // Check if the region has a binding.
1739
91.3k
  if (const Optional<SVal> &V = B.getDirectBinding(R))
1740
30.0k
    return *V;
1741
1742
  // Is the field declared constant and has an in-class initializer?
1743
61.2k
  const FieldDecl *FD = R->getDecl();
1744
61.2k
  QualType Ty = FD->getType();
1745
61.2k
  if (Ty.isConstQualified())
1746
49
    if (const Expr *Init = FD->getInClassInitializer())
1747
0
      if (Optional<SVal> V = svalBuilder.getConstantVal(Init))
1748
0
        return *V;
1749
1750
  // If the containing record was initialized, try to get its constant value.
1751
61.2k
  const MemRegion* superR = R->getSuperRegion();
1752
61.2k
  if (const auto *VR = dyn_cast<VarRegion>(superR)) {
1753
14.8k
    const VarDecl *VD = VR->getDecl();
1754
14.8k
    QualType RecordVarTy = VD->getType();
1755
14.8k
    unsigned Index = FD->getFieldIndex();
1756
    // Either the record variable or the field has an initializer that we can
1757
    // trust. We trust initializers of constants and, additionally, respect
1758
    // initializers of globals when analyzing main().
1759
14.8k
    if (RecordVarTy.isConstQualified() || 
Ty.isConstQualified()14.5k
||
1760
14.5k
        (B.isMainAnalysis() && 
VD->hasGlobalStorage()3
))
1761
349
      if (const Expr *Init = VD->getAnyInitializer())
1762
136
        if (const auto *InitList = dyn_cast<InitListExpr>(Init)) {
1763
97
          if (Index < InitList->getNumInits()) {
1764
96
            if (const Expr *FieldInit = InitList->getInit(Index))
1765
96
              if (Optional<SVal> V = svalBuilder.getConstantVal(FieldInit))
1766
96
                return *V;
1767
1
          } else {
1768
1
            return svalBuilder.makeZeroVal(Ty);
1769
1
          }
1770
61.1k
        }
1771
14.8k
  }
1772
1773
61.1k
  return getBindingForFieldOrElementCommon(B, R, Ty);
1774
61.1k
}
1775
1776
Optional<SVal>
1777
RegionStoreManager::getBindingForDerivedDefaultValue(RegionBindingsConstRef B,
1778
                                                     const MemRegion *superR,
1779
                                                     const TypedValueRegion *R,
1780
182k
                                                     QualType Ty) {
1781
1782
182k
  if (const Optional<SVal> &D = B.getDefaultBinding(superR)) {
1783
13.9k
    const SVal &val = D.getValue();
1784
13.9k
    if (SymbolRef parentSym = val.getAsSymbol())
1785
12.6k
      return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1786
1787
1.32k
    if (val.isZeroConstant())
1788
357
      return svalBuilder.makeZeroVal(Ty);
1789
1790
969
    if (val.isUnknownOrUndef())
1791
947
      return val;
1792
1793
    // Lazy bindings are usually handled through getExistingLazyBinding().
1794
    // We should unify these two code paths at some point.
1795
22
    if (val.getAs<nonloc::LazyCompoundVal>() ||
1796
10
        val.getAs<nonloc::CompoundVal>())
1797
22
      return val;
1798
1799
0
    llvm_unreachable("Unknown default value");
1800
0
  }
1801
1802
168k
  return None;
1803
168k
}
1804
1805
SVal RegionStoreManager::getLazyBinding(const SubRegion *LazyBindingRegion,
1806
444
                                        RegionBindingsRef LazyBinding) {
1807
444
  SVal Result;
1808
444
  if (const ElementRegion *ER = dyn_cast<ElementRegion>(LazyBindingRegion))
1809
154
    Result = getBindingForElement(LazyBinding, ER);
1810
290
  else
1811
290
    Result = getBindingForField(LazyBinding,
1812
290
                                cast<FieldRegion>(LazyBindingRegion));
1813
1814
  // FIXME: This is a hack to deal with RegionStore's inability to distinguish a
1815
  // default value for /part/ of an aggregate from a default value for the
1816
  // /entire/ aggregate. The most common case of this is when struct Outer
1817
  // has as its first member a struct Inner, which is copied in from a stack
1818
  // variable. In this case, even if the Outer's default value is symbolic, 0,
1819
  // or unknown, it gets overridden by the Inner's default value of undefined.
1820
  //
1821
  // This is a general problem -- if the Inner is zero-initialized, the Outer
1822
  // will now look zero-initialized. The proper way to solve this is with a
1823
  // new version of RegionStore that tracks the extent of a binding as well
1824
  // as the offset.
1825
  //
1826
  // This hack only takes care of the undefined case because that can very
1827
  // quickly result in a warning.
1828
444
  if (Result.isUndef())
1829
7
    Result = UnknownVal();
1830
1831
444
  return Result;
1832
444
}
1833
1834
SVal
1835
RegionStoreManager::getBindingForFieldOrElementCommon(RegionBindingsConstRef B,
1836
                                                      const TypedValueRegion *R,
1837
71.8k
                                                      QualType Ty) {
1838
1839
  // At this point we have already checked in either getBindingForElement or
1840
  // getBindingForField if 'R' has a direct binding.
1841
1842
  // Lazy binding?
1843
71.8k
  Store lazyBindingStore = nullptr;
1844
71.8k
  const SubRegion *lazyBindingRegion = nullptr;
1845
71.8k
  std::tie(lazyBindingStore, lazyBindingRegion) = findLazyBinding(B, R, R);
1846
71.8k
  if (lazyBindingRegion)
1847
444
    return getLazyBinding(lazyBindingRegion,
1848
444
                          getRegionBindings(lazyBindingStore));
1849
1850
  // Record whether or not we see a symbolic index.  That can completely
1851
  // be out of scope of our lookup.
1852
71.4k
  bool hasSymbolicIndex = false;
1853
1854
  // FIXME: This is a hack to deal with RegionStore's inability to distinguish a
1855
  // default value for /part/ of an aggregate from a default value for the
1856
  // /entire/ aggregate. The most common case of this is when struct Outer
1857
  // has as its first member a struct Inner, which is copied in from a stack
1858
  // variable. In this case, even if the Outer's default value is symbolic, 0,
1859
  // or unknown, it gets overridden by the Inner's default value of undefined.
1860
  //
1861
  // This is a general problem -- if the Inner is zero-initialized, the Outer
1862
  // will now look zero-initialized. The proper way to solve this is with a
1863
  // new version of RegionStore that tracks the extent of a binding as well
1864
  // as the offset.
1865
  //
1866
  // This hack only takes care of the undefined case because that can very
1867
  // quickly result in a warning.
1868
71.4k
  bool hasPartialLazyBinding = false;
1869
1870
71.4k
  const SubRegion *SR = R;
1871
238k
  while (SR) {
1872
175k
    const MemRegion *Base = SR->getSuperRegion();
1873
175k
    if (Optional<SVal> D = getBindingForDerivedDefaultValue(B, Base, R, Ty)) {
1874
8.62k
      if (D->getAs<nonloc::LazyCompoundVal>()) {
1875
12
        hasPartialLazyBinding = true;
1876
12
        break;
1877
12
      }
1878
1879
8.61k
      return *D;
1880
8.61k
    }
1881
1882
167k
    if (const ElementRegion *ER = dyn_cast<ElementRegion>(Base)) {
1883
37.2k
      NonLoc index = ER->getIndex();
1884
37.2k
      if (!index.isConstant())
1885
27.0k
        hasSymbolicIndex = true;
1886
37.2k
    }
1887
1888
    // If our super region is a field or element itself, walk up the region
1889
    // hierarchy to see if there is a default value installed in an ancestor.
1890
167k
    SR = dyn_cast<SubRegion>(Base);
1891
167k
  }
1892
1893
62.8k
  if (R->hasStackNonParametersStorage()) {
1894
16.7k
    if (isa<ElementRegion>(R)) {
1895
      // Currently we don't reason specially about Clang-style vectors.  Check
1896
      // if superR is a vector and if so return Unknown.
1897
2.64k
      if (const TypedValueRegion *typedSuperR =
1898
2.63k
            dyn_cast<TypedValueRegion>(R->getSuperRegion())) {
1899
2.63k
        if (typedSuperR->getValueType()->isVectorType())
1900
6
          return UnknownVal();
1901
16.7k
      }
1902
2.64k
    }
1903
1904
    // FIXME: We also need to take ElementRegions with symbolic indexes into
1905
    // account.  This case handles both directly accessing an ElementRegion
1906
    // with a symbolic offset, but also fields within an element with
1907
    // a symbolic offset.
1908
16.7k
    if (hasSymbolicIndex)
1909
11
      return UnknownVal();
1910
1911
    // Additionally allow introspection of a block's internal layout.
1912
16.6k
    if (!hasPartialLazyBinding && 
!isa<BlockDataRegion>(R->getBaseRegion())16.6k
)
1913
16.6k
      return UndefinedVal();
1914
46.1k
  }
1915
1916
  // All other values are symbolic.
1917
46.1k
  return svalBuilder.getRegionValueSymbolVal(R);
1918
46.1k
}
1919
1920
SVal RegionStoreManager::getBindingForObjCIvar(RegionBindingsConstRef B,
1921
2.51k
                                               const ObjCIvarRegion* R) {
1922
  // Check if the region has a binding.
1923
2.51k
  if (const Optional<SVal> &V = B.getDirectBinding(R))
1924
1.11k
    return *V;
1925
1926
1.40k
  const MemRegion *superR = R->getSuperRegion();
1927
1928
  // Check if the super region has a default binding.
1929
1.40k
  if (const Optional<SVal> &V = B.getDefaultBinding(superR)) {
1930
66
    if (SymbolRef parentSym = V->getAsSymbol())
1931
66
      return svalBuilder.getDerivedRegionValueSymbolVal(parentSym, R);
1932
1933
    // Other cases: give up.
1934
0
    return UnknownVal();
1935
0
  }
1936
1937
1.33k
  return getBindingForLazySymbol(R);
1938
1.33k
}
1939
1940
SVal RegionStoreManager::getBindingForVar(RegionBindingsConstRef B,
1941
304k
                                          const VarRegion *R) {
1942
1943
  // Check if the region has a binding.
1944
304k
  if (Optional<SVal> V = B.getDirectBinding(R))
1945
180k
    return *V;
1946
1947
123k
  if (Optional<SVal> V = B.getDefaultBinding(R))
1948
13
    return *V;
1949
1950
  // Lazily derive a value for the VarRegion.
1951
123k
  const VarDecl *VD = R->getDecl();
1952
123k
  const MemSpaceRegion *MS = R->getMemorySpace();
1953
1954
  // Arguments are always symbolic.
1955
123k
  if (isa<StackArgumentsSpaceRegion>(MS))
1956
58.3k
    return svalBuilder.getRegionValueSymbolVal(R);
1957
1958
  // Is 'VD' declared constant?  If so, retrieve the constant value.
1959
65.4k
  if (VD->getType().isConstQualified()) {
1960
788
    if (const Expr *Init = VD->getAnyInitializer()) {
1961
552
      if (Optional<SVal> V = svalBuilder.getConstantVal(Init))
1962
515
        return *V;
1963
1964
      // If the variable is const qualified and has an initializer but
1965
      // we couldn't evaluate initializer to a value, treat the value as
1966
      // unknown.
1967
37
      return UnknownVal();
1968
37
    }
1969
788
  }
1970
1971
  // This must come after the check for constants because closure-captured
1972
  // constant variables may appear in UnknownSpaceRegion.
1973
64.9k
  if (isa<UnknownSpaceRegion>(MS))
1974
138
    return svalBuilder.getRegionValueSymbolVal(R);
1975
1976
64.7k
  if (isa<GlobalsSpaceRegion>(MS)) {
1977
6.87k
    QualType T = VD->getType();
1978
1979
    // If we're in main(), then global initializers have not become stale yet.
1980
6.87k
    if (B.isMainAnalysis())
1981
3
      if (const Expr *Init = VD->getAnyInitializer())
1982
1
        if (Optional<SVal> V = svalBuilder.getConstantVal(Init))
1983
1
          return *V;
1984
1985
    // Function-scoped static variables are default-initialized to 0; if they
1986
    // have an initializer, it would have been processed by now.
1987
    // FIXME: This is only true when we're starting analysis from main().
1988
    // We're losing a lot of coverage here.
1989
6.87k
    if (isa<StaticGlobalSpaceRegion>(MS))
1990
203
      return svalBuilder.makeZeroVal(T);
1991
1992
6.66k
    if (Optional<SVal> V = getBindingForDerivedDefaultValue(B, MS, R, T)) {
1993
5.31k
      assert(!V->getAs<nonloc::LazyCompoundVal>());
1994
5.31k
      return V.getValue();
1995
5.31k
    }
1996
1997
1.35k
    return svalBuilder.getRegionValueSymbolVal(R);
1998
1.35k
  }
1999
2000
57.9k
  return UndefinedVal();
2001
57.9k
}
2002
2003
1.33k
SVal RegionStoreManager::getBindingForLazySymbol(const TypedValueRegion *R) {
2004
  // All other values are symbolic.
2005
1.33k
  return svalBuilder.getRegionValueSymbolVal(R);
2006
1.33k
}
2007
2008
const RegionStoreManager::SValListTy &
2009
14.2k
RegionStoreManager::getInterestingValues(nonloc::LazyCompoundVal LCV) {
2010
  // First, check the cache.
2011
14.2k
  LazyBindingsMapTy::iterator I = LazyBindingsMap.find(LCV.getCVData());
2012
14.2k
  if (I != LazyBindingsMap.end())
2013
13.1k
    return I->second;
2014
2015
  // If we don't have a list of values cached, start constructing it.
2016
1.08k
  SValListTy List;
2017
2018
1.08k
  const SubRegion *LazyR = LCV.getRegion();
2019
1.08k
  RegionBindingsRef B = getRegionBindings(LCV.getStore());
2020
2021
  // If this region had /no/ bindings at the time, there are no interesting
2022
  // values to return.
2023
1.08k
  const ClusterBindings *Cluster = B.lookup(LazyR->getBaseRegion());
2024
1.08k
  if (!Cluster)
2025
259
    return (LazyBindingsMap[LCV.getCVData()] = std::move(List));
2026
2027
821
  SmallVector<BindingPair, 32> Bindings;
2028
821
  collectSubRegionBindings(Bindings, svalBuilder, *Cluster, LazyR,
2029
821
                           /*IncludeAllDefaultBindings=*/true);
2030
821
  for (SmallVectorImpl<BindingPair>::const_iterator I = Bindings.begin(),
2031
821
                                                    E = Bindings.end();
2032
1.85k
       I != E; 
++I1.03k
) {
2033
1.03k
    SVal V = I->second;
2034
1.03k
    if (V.isUnknownOrUndef() || 
V.isConstant()945
)
2035
340
      continue;
2036
2037
693
    if (Optional<nonloc::LazyCompoundVal> InnerLCV =
2038
6
            V.getAs<nonloc::LazyCompoundVal>()) {
2039
6
      const SValListTy &InnerList = getInterestingValues(*InnerLCV);
2040
6
      List.insert(List.end(), InnerList.begin(), InnerList.end());
2041
6
      continue;
2042
6
    }
2043
2044
687
    List.push_back(V);
2045
687
  }
2046
2047
821
  return (LazyBindingsMap[LCV.getCVData()] = std::move(List));
2048
821
}
2049
2050
NonLoc RegionStoreManager::createLazyBinding(RegionBindingsConstRef B,
2051
54.2k
                                             const TypedValueRegion *R) {
2052
54.2k
  if (Optional<nonloc::LazyCompoundVal> V =
2053
146
        getExistingLazyBinding(svalBuilder, B, R, false))
2054
146
    return *V;
2055
2056
54.1k
  return svalBuilder.makeLazyCompoundVal(StoreRef(B.asStore(), *this), R);
2057
54.1k
}
2058
2059
57.7k
static bool isRecordEmpty(const RecordDecl *RD) {
2060
57.7k
  if (!RD->field_empty())
2061
50.9k
    return false;
2062
6.82k
  if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD))
2063
6.69k
    return CRD->getNumBases() == 0;
2064
133
  return true;
2065
133
}
2066
2067
SVal RegionStoreManager::getBindingForStruct(RegionBindingsConstRef B,
2068
58.3k
                                             const TypedValueRegion *R) {
2069
58.3k
  const RecordDecl *RD = R->getValueType()->castAs<RecordType>()->getDecl();
2070
58.3k
  if (!RD->getDefinition() || 
isRecordEmpty(RD)57.7k
)
2071
6.16k
    return UnknownVal();
2072
2073
52.1k
  return createLazyBinding(B, R);
2074
52.1k
}
2075
2076
SVal RegionStoreManager::getBindingForArray(RegionBindingsConstRef B,
2077
2.03k
                                            const TypedValueRegion *R) {
2078
2.03k
  assert(Ctx.getAsConstantArrayType(R->getValueType()) &&
2079
2.03k
         "Only constant array types can have compound bindings.");
2080
2081
2.03k
  return createLazyBinding(B, R);
2082
2.03k
}
2083
2084
bool RegionStoreManager::includedInBindings(Store store,
2085
14.5k
                                            const MemRegion *region) const {
2086
14.5k
  RegionBindingsRef B = getRegionBindings(store);
2087
14.5k
  region = region->getBaseRegion();
2088
2089
  // Quick path: if the base is the head of a cluster, the region is live.
2090
14.5k
  if (B.lookup(region))
2091
0
    return true;
2092
2093
  // Slow path: if the region is the VALUE of any binding, it is live.
2094
60.6k
  
for (RegionBindingsRef::iterator RI = B.begin(), RE = B.end(); 14.5k
RI != RE;
++RI46.1k
) {
2095
46.1k
    const ClusterBindings &Cluster = RI.getData();
2096
46.1k
    for (ClusterBindings::iterator CI = Cluster.begin(), CE = Cluster.end();
2097
92.7k
         CI != CE; 
++CI46.5k
) {
2098
46.5k
      const SVal &D = CI.getData();
2099
46.5k
      if (const MemRegion *R = D.getAsRegion())
2100
9.01k
        if (R->getBaseRegion() == region)
2101
0
          return true;
2102
46.5k
    }
2103
46.1k
  }
2104
2105
14.5k
  return false;
2106
14.5k
}
2107
2108
//===----------------------------------------------------------------------===//
2109
// Binding values to regions.
2110
//===----------------------------------------------------------------------===//
2111
2112
6
StoreRef RegionStoreManager::killBinding(Store ST, Loc L) {
2113
6
  if (Optional<loc::MemRegionVal> LV = L.getAs<loc::MemRegionVal>())
2114
0
    if (const MemRegion* R = LV->getRegion())
2115
0
      return StoreRef(getRegionBindings(ST).removeBinding(R)
2116
0
                                           .asImmutableMap()
2117
0
                                           .getRootWithoutRetain(),
2118
0
                      *this);
2119
2120
6
  return StoreRef(ST, *this);
2121
6
}
2122
2123
RegionBindingsRef
2124
197k
RegionStoreManager::bind(RegionBindingsConstRef B, Loc L, SVal V) {
2125
197k
  if (L.getAs<loc::ConcreteInt>())
2126
5
    return B;
2127
2128
  // If we get here, the location should be a region.
2129
197k
  const MemRegion *R = L.castAs<loc::MemRegionVal>().getRegion();
2130
2131
  // Check if the region is a struct region.
2132
197k
  if (const TypedValueRegion* TR = dyn_cast<TypedValueRegion>(R)) {
2133
197k
    QualType Ty = TR->getValueType();
2134
197k
    if (Ty->isArrayType())
2135
1.30k
      return bindArray(B, TR, V);
2136
195k
    if (Ty->isStructureOrClassType())
2137
23.3k
      return bindStruct(B, TR, V);
2138
172k
    if (Ty->isVectorType())
2139
11
      return bindVector(B, TR, V);
2140
172k
    if (Ty->isUnionType())
2141
71
      return bindAggregate(B, TR, V);
2142
172k
  }
2143
2144
172k
  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(R)) {
2145
    // Binding directly to a symbolic region should be treated as binding
2146
    // to element 0.
2147
558
    QualType T = SR->getSymbol()->getType();
2148
558
    if (T->isAnyPointerType() || 
T->isReferenceType()130
)
2149
558
      T = T->getPointeeType();
2150
2151
558
    R = GetElementZeroRegion(SR, T);
2152
558
  }
2153
2154
172k
  assert((!isa<CXXThisRegion>(R) || !B.lookup(R)) &&
2155
172k
         "'this' pointer is not an l-value and is not assignable");
2156
2157
  // Clear out bindings that may overlap with this binding.
2158
172k
  RegionBindingsRef NewB = removeSubRegionBindings(B, cast<SubRegion>(R));
2159
172k
  return NewB.addBinding(BindingKey::Make(R, BindingKey::Direct), V);
2160
172k
}
2161
2162
RegionBindingsRef
2163
RegionStoreManager::setImplicitDefaultValue(RegionBindingsConstRef B,
2164
                                            const MemRegion *R,
2165
320
                                            QualType T) {
2166
320
  SVal V;
2167
2168
320
  if (Loc::isLocType(T))
2169
10
    V = svalBuilder.makeNull();
2170
310
  else if (T->isIntegralOrEnumerationType())
2171
262
    V = svalBuilder.makeZeroVal(T);
2172
48
  else if (T->isStructureOrClassType() || 
T->isArrayType()14
) {
2173
    // Set the default value to a zero constant when it is a structure
2174
    // or array.  The type doesn't really matter.
2175
34
    V = svalBuilder.makeZeroVal(Ctx.IntTy);
2176
34
  }
2177
14
  else {
2178
    // We can't represent values of this type, but we still need to set a value
2179
    // to record that the region has been initialized.
2180
    // If this assertion ever fires, a new case should be added above -- we
2181
    // should know how to default-initialize any value we can symbolicate.
2182
14
    assert(!SymbolManager::canSymbolicate(T) && "This type is representable");
2183
14
    V = UnknownVal();
2184
14
  }
2185
2186
320
  return B.addBinding(R, BindingKey::Default, V);
2187
320
}
2188
2189
RegionBindingsRef
2190
RegionStoreManager::bindArray(RegionBindingsConstRef B,
2191
                              const TypedValueRegion* R,
2192
1.52k
                              SVal Init) {
2193
2194
1.52k
  const ArrayType *AT =cast<ArrayType>(Ctx.getCanonicalType(R->getValueType()));
2195
1.52k
  QualType ElementTy = AT->getElementType();
2196
1.52k
  Optional<uint64_t> Size;
2197
2198
1.52k
  if (const ConstantArrayType* CAT = dyn_cast<ConstantArrayType>(AT))
2199
1.51k
    Size = CAT->getSize().getZExtValue();
2200
2201
  // Check if the init expr is a literal. If so, bind the rvalue instead.
2202
  // FIXME: It's not responsibility of the Store to transform this lvalue
2203
  // to rvalue. ExprEngine or maybe even CFG should do this before binding.
2204
1.52k
  if (Optional<loc::MemRegionVal> MRV = Init.getAs<loc::MemRegionVal>()) {
2205
456
    SVal V = getBinding(B.asStore(), *MRV, R->getValueType());
2206
456
    return bindAggregate(B, R, V);
2207
456
  }
2208
2209
  // Handle lazy compound values.
2210
1.06k
  if (Init.getAs<nonloc::LazyCompoundVal>())
2211
8
    return bindAggregate(B, R, Init);
2212
2213
1.05k
  if (Init.isUnknown())
2214
46
    return bindAggregate(B, R, UnknownVal());
2215
2216
  // Remaining case: explicit compound values.
2217
1.01k
  const nonloc::CompoundVal& CV = Init.castAs<nonloc::CompoundVal>();
2218
1.01k
  nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
2219
1.01k
  uint64_t i = 0;
2220
2221
1.01k
  RegionBindingsRef NewB(B);
2222
2223
3.88k
  for (; Size.hasValue() ? 
i < Size.getValue()3.86k
:
true14
;
++i, ++VI2.86k
) {
2224
    // The init list might be shorter than the array length.
2225
3.18k
    if (VI == VE)
2226
320
      break;
2227
2228
2.86k
    const NonLoc &Idx = svalBuilder.makeArrayIndex(i);
2229
2.86k
    const ElementRegion *ER = MRMgr.getElementRegion(ElementTy, Idx, R, Ctx);
2230
2231
2.86k
    if (ElementTy->isStructureOrClassType())
2232
190
      NewB = bindStruct(NewB, ER, *VI);
2233
2.67k
    else if (ElementTy->isArrayType())
2234
81
      NewB = bindArray(NewB, ER, *VI);
2235
2.59k
    else
2236
2.59k
      NewB = bind(NewB, loc::MemRegionVal(ER), *VI);
2237
2.86k
  }
2238
2239
  // If the init list is shorter than the array length (or the array has
2240
  // variable length), set the array default value. Values that are already set
2241
  // are not overwritten.
2242
1.01k
  if (!Size.hasValue() || 
i < Size.getValue()1.00k
)
2243
320
    NewB = setImplicitDefaultValue(NewB, R, ElementTy);
2244
2245
1.01k
  return NewB;
2246
1.01k
}
2247
2248
RegionBindingsRef RegionStoreManager::bindVector(RegionBindingsConstRef B,
2249
                                                 const TypedValueRegion* R,
2250
11
                                                 SVal V) {
2251
11
  QualType T = R->getValueType();
2252
11
  const VectorType *VT = T->castAs<VectorType>(); // Use castAs for typedefs.
2253
2254
  // Handle lazy compound values and symbolic values.
2255
11
  if (V.getAs<nonloc::LazyCompoundVal>() || V.getAs<nonloc::SymbolVal>())
2256
0
    return bindAggregate(B, R, V);
2257
2258
  // We may get non-CompoundVal accidentally due to imprecise cast logic or
2259
  // that we are binding symbolic struct value. Kill the field values, and if
2260
  // the value is symbolic go and bind it as a "default" binding.
2261
11
  if (!V.getAs<nonloc::CompoundVal>()) {
2262
3
    return bindAggregate(B, R, UnknownVal());
2263
3
  }
2264
2265
8
  QualType ElemType = VT->getElementType();
2266
8
  nonloc::CompoundVal CV = V.castAs<nonloc::CompoundVal>();
2267
8
  nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
2268
8
  unsigned index = 0, numElements = VT->getNumElements();
2269
8
  RegionBindingsRef NewB(B);
2270
2271
28
  for ( ; index != numElements ; 
++index20
) {
2272
20
    if (VI == VE)
2273
0
      break;
2274
2275
20
    NonLoc Idx = svalBuilder.makeArrayIndex(index);
2276
20
    const ElementRegion *ER = MRMgr.getElementRegion(ElemType, Idx, R, Ctx);
2277
2278
20
    if (ElemType->isArrayType())
2279
0
      NewB = bindArray(NewB, ER, *VI);
2280
20
    else if (ElemType->isStructureOrClassType())
2281
0
      NewB = bindStruct(NewB, ER, *VI);
2282
20
    else
2283
20
      NewB = bind(NewB, loc::MemRegionVal(ER), *VI);
2284
20
  }
2285
8
  return NewB;
2286
8
}
2287
2288
Optional<RegionBindingsRef>
2289
RegionStoreManager::tryBindSmallStruct(RegionBindingsConstRef B,
2290
                                       const TypedValueRegion *R,
2291
                                       const RecordDecl *RD,
2292
22.1k
                                       nonloc::LazyCompoundVal LCV) {
2293
22.1k
  FieldVector Fields;
2294
2295
22.1k
  if (const CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(RD))
2296
21.9k
    if (Class->getNumBases() != 0 || 
Class->getNumVBases() != 021.9k
)
2297
75
      return None;
2298
2299
22.5k
  
for (const auto *FD : RD->fields())22.0k
{
2300
22.5k
    if (FD->isUnnamedBitfield())
2301
8
      continue;
2302
2303
    // If there are too many fields, or if any of the fields are aggregates,
2304
    // just use the LCV as a default binding.
2305
22.5k
    if (Fields.size() == SmallStructLimit)
2306
106
      return None;
2307
2308
22.4k
    QualType Ty = FD->getType();
2309
22.4k
    if (!(Ty->isScalarType() || 
Ty->isReferenceType()495
))
2310
187
      return None;
2311
2312
22.2k
    Fields.push_back(FD);
2313
22.2k
  }
2314
2315
21.7k
  RegionBindingsRef NewB = B;
2316
2317
43.7k
  for (FieldVector::iterator I = Fields.begin(), E = Fields.end(); I != E; 
++I22.0k
){
2318
22.0k
    const FieldRegion *SourceFR = MRMgr.getFieldRegion(*I, LCV.getRegion());
2319
22.0k
    SVal V = getBindingForField(getRegionBindings(LCV.getStore()), SourceFR);
2320
2321
22.0k
    const FieldRegion *DestFR = MRMgr.getFieldRegion(*I, R);
2322
22.0k
    NewB = bind(NewB, loc::MemRegionVal(DestFR), V);
2323
22.0k
  }
2324
2325
21.7k
  return NewB;
2326
22.0k
}
2327
2328
RegionBindingsRef RegionStoreManager::bindStruct(RegionBindingsConstRef B,
2329
                                                 const TypedValueRegion* R,
2330
23.6k
                                                 SVal V) {
2331
23.6k
  if (!Features.supportsFields())
2332
0
    return B;
2333
2334
23.6k
  QualType T = R->getValueType();
2335
23.6k
  assert(T->isStructureOrClassType());
2336
2337
23.6k
  const RecordType* RT = T->castAs<RecordType>();
2338
23.6k
  const RecordDecl *RD = RT->getDecl();
2339
2340
23.6k
  if (!RD->isCompleteDefinition())
2341
0
    return B;
2342
2343
  // Handle lazy compound values and symbolic values.
2344
23.6k
  if (Optional<nonloc::LazyCompoundVal> LCV =
2345
22.1k
        V.getAs<nonloc::LazyCompoundVal>()) {
2346
22.1k
    if (Optional<RegionBindingsRef> NewB = tryBindSmallStruct(B, R, RD, *LCV))
2347
21.7k
      return *NewB;
2348
368
    return bindAggregate(B, R, V);
2349
368
  }
2350
1.52k
  if (V.getAs<nonloc::SymbolVal>())
2351
452
    return bindAggregate(B, R, V);
2352
2353
  // We may get non-CompoundVal accidentally due to imprecise cast logic or
2354
  // that we are binding symbolic struct value. Kill the field values, and if
2355
  // the value is symbolic go and bind it as a "default" binding.
2356
1.07k
  if (V.isUnknown() || 
!V.getAs<nonloc::CompoundVal>()1.00k
)
2357
78
    return bindAggregate(B, R, UnknownVal());
2358
2359
  // The raw CompoundVal is essentially a symbolic InitListExpr: an (immutable)
2360
  // list of other values. It appears pretty much only when there's an actual
2361
  // initializer list expression in the program, and the analyzer tries to
2362
  // unwrap it as soon as possible.
2363
  // This code is where such unwrap happens: when the compound value is put into
2364
  // the object that it was supposed to initialize (it's an *initializer* list,
2365
  // after all), instead of binding the whole value to the whole object, we bind
2366
  // sub-values to sub-objects. Sub-values may themselves be compound values,
2367
  // and in this case the procedure becomes recursive.
2368
  // FIXME: The annoying part about compound values is that they don't carry
2369
  // any sort of information about which value corresponds to which sub-object.
2370
  // It's simply a list of values in the middle of nowhere; we expect to match
2371
  // them to sub-objects, essentially, "by index": first value binds to
2372
  // the first field, second value binds to the second field, etc.
2373
  // It would have been much safer to organize non-lazy compound values as
2374
  // a mapping from fields/bases to values.
2375
998
  const nonloc::CompoundVal& CV = V.castAs<nonloc::CompoundVal>();
2376
998
  nonloc::CompoundVal::iterator VI = CV.begin(), VE = CV.end();
2377
2378
998
  RegionBindingsRef NewB(B);
2379
2380
  // In C++17 aggregates may have base classes, handle those as well.
2381
  // They appear before fields in the initializer list / compound value.
2382
998
  if (const auto *CRD = dyn_cast<CXXRecordDecl>(RD)) {
2383
    // If the object was constructed with a constructor, its value is a
2384
    // LazyCompoundVal. If it's a raw CompoundVal, it means that we're
2385
    // performing aggregate initialization. The only exception from this
2386
    // rule is sending an Objective-C++ message that returns a C++ object
2387
    // to a nil receiver; in this case the semantics is to return a
2388
    // zero-initialized object even if it's a C++ object that doesn't have
2389
    // this sort of constructor; the CompoundVal is empty in this case.
2390
768
    assert((CRD->isAggregate() || (Ctx.getLangOpts().ObjC && VI == VE)) &&
2391
768
           "Non-aggregates are constructed with a constructor!");
2392
2393
66
    for (const auto &B : CRD->bases()) {
2394
      // (Multiple inheritance is fine though.)
2395
66
      assert(!B.isVirtual() && "Aggregates cannot have virtual base classes!");
2396
2397
66
      if (VI == VE)
2398
0
        break;
2399
2400
66
      QualType BTy = B.getType();
2401
66
      assert(BTy->isStructureOrClassType() && "Base classes must be classes!");
2402
2403
66
      const CXXRecordDecl *BRD = BTy->getAsCXXRecordDecl();
2404
66
      assert(BRD && "Base classes must be C++ classes!");
2405
2406
66
      const CXXBaseObjectRegion *BR =
2407
66
          MRMgr.getCXXBaseObjectRegion(BRD, R, /*IsVirtual=*/false);
2408
2409
66
      NewB = bindStruct(NewB, BR, *VI);
2410
2411
66
      ++VI;
2412
66
    }
2413
768
  }
2414
2415
998
  RecordDecl::field_iterator FI, FE;
2416
2417
1.94k
  for (FI = RD->field_begin(), FE = RD->field_end(); FI != FE; 
++FI946
) {
2418
2419
953
    if (VI == VE)
2420
7
      break;
2421
2422
    // Skip any unnamed bitfields to stay in sync with the initializers.
2423
946
    if (FI->isUnnamedBitfield())
2424
4
      continue;
2425
2426
942
    QualType FTy = FI->getType();
2427
942
    const FieldRegion* FR = MRMgr.getFieldRegion(*FI, R);
2428
2429
942
    if (FTy->isArrayType())
2430
140
      NewB = bindArray(NewB, FR, *VI);
2431
802
    else if (FTy->isStructureOrClassType())
2432
45
      NewB = bindStruct(NewB, FR, *VI);
2433
757
    else
2434
757
      NewB = bind(NewB, loc::MemRegionVal(FR), *VI);
2435
942
    ++VI;
2436
942
  }
2437
2438
  // There may be fewer values in the initialize list than the fields of struct.
2439
998
  if (FI != FE) {
2440
7
    NewB = NewB.addBinding(R, BindingKey::Default,
2441
7
                           svalBuilder.makeIntVal(0, false));
2442
7
  }
2443
2444
998
  return NewB;
2445
998
}
2446
2447
RegionBindingsRef
2448
RegionStoreManager::bindAggregate(RegionBindingsConstRef B,
2449
                                  const TypedRegion *R,
2450
1.48k
                                  SVal Val) {
2451
  // Remove the old bindings, using 'R' as the root of all regions
2452
  // we will invalidate. Then add the new binding.
2453
1.48k
  return removeSubRegionBindings(B, R).addBinding(R, BindingKey::Default, Val);
2454
1.48k
}
2455
2456
//===----------------------------------------------------------------------===//
2457
// State pruning.
2458
//===----------------------------------------------------------------------===//
2459
2460
namespace {
2461
class RemoveDeadBindingsWorker
2462
    : public ClusterAnalysis<RemoveDeadBindingsWorker> {
2463
  SmallVector<const SymbolicRegion *, 12> Postponed;
2464
  SymbolReaper &SymReaper;
2465
  const StackFrameContext *CurrentLCtx;
2466
2467
public:
2468
  RemoveDeadBindingsWorker(RegionStoreManager &rm,
2469
                           ProgramStateManager &stateMgr,
2470
                           RegionBindingsRef b, SymbolReaper &symReaper,
2471
                           const StackFrameContext *LCtx)
2472
    : ClusterAnalysis<RemoveDeadBindingsWorker>(rm, stateMgr, b),
2473
361k
      SymReaper(symReaper), CurrentLCtx(LCtx) {}
2474
2475
  // Called by ClusterAnalysis.
2476
  void VisitAddedToCluster(const MemRegion *baseR, const ClusterBindings &C);
2477
  void VisitCluster(const MemRegion *baseR, const ClusterBindings *C);
2478
  using ClusterAnalysis<RemoveDeadBindingsWorker>::VisitCluster;
2479
2480
  using ClusterAnalysis::AddToWorkList;
2481
2482
  bool AddToWorkList(const MemRegion *R);
2483
2484
  bool UpdatePostponed();
2485
  void VisitBinding(SVal V);
2486
};
2487
}
2488
2489
1.18M
bool RemoveDeadBindingsWorker::AddToWorkList(const MemRegion *R) {
2490
1.18M
  const MemRegion *BaseR = R->getBaseRegion();
2491
1.18M
  return AddToWorkList(WorkListElement(BaseR), getCluster(BaseR));
2492
1.18M
}
2493
2494
void RemoveDeadBindingsWorker::VisitAddedToCluster(const MemRegion *baseR,
2495
1.33M
                                                   const ClusterBindings &C) {
2496
2497
1.33M
  if (const VarRegion *VR = dyn_cast<VarRegion>(baseR)) {
2498
653k
    if (SymReaper.isLive(VR))
2499
528k
      AddToWorkList(baseR, &C);
2500
2501
653k
    return;
2502
653k
  }
2503
2504
679k
  if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(baseR)) {
2505
53.6k
    if (SymReaper.isLive(SR->getSymbol()))
2506
41.2k
      AddToWorkList(SR, &C);
2507
12.4k
    else
2508
12.4k
      Postponed.push_back(SR);
2509
2510
53.6k
    return;
2511
53.6k
  }
2512
2513
625k
  if (isa<NonStaticGlobalSpaceRegion>(baseR)) {
2514
464k
    AddToWorkList(baseR, &C);
2515
464k
    return;
2516
464k
  }
2517
2518
  // CXXThisRegion in the current or parent location context is live.
2519
161k
  if (const CXXThisRegion *TR = dyn_cast<CXXThisRegion>(baseR)) {
2520
137k
    const auto *StackReg =
2521
137k
        cast<StackArgumentsSpaceRegion>(TR->getSuperRegion());
2522
137k
    const StackFrameContext *RegCtx = StackReg->getStackFrame();
2523
137k
    if (CurrentLCtx &&
2524
136k
        (RegCtx == CurrentLCtx || 
RegCtx->isParentOf(CurrentLCtx)84.9k
))
2525
120k
      AddToWorkList(TR, &C);
2526
137k
  }
2527
161k
}
2528
2529
void RemoveDeadBindingsWorker::VisitCluster(const MemRegion *baseR,
2530
1.92M
                                            const ClusterBindings *C) {
2531
1.92M
  if (!C)
2532
702k
    return;
2533
2534
  // Mark the symbol for any SymbolicRegion with live bindings as live itself.
2535
  // This means we should continue to track that symbol.
2536
1.22M
  if (const SymbolicRegion *SymR = dyn_cast<SymbolicRegion>(baseR))
2537
46.6k
    SymReaper.markLive(SymR->getSymbol());
2538
2539
2.73M
  for (ClusterBindings::iterator I = C->begin(), E = C->end(); I != E; 
++I1.51M
) {
2540
    // Element index of a binding key is live.
2541
1.51M
    SymReaper.markElementIndicesLive(I.getKey().getRegion());
2542
2543
1.51M
    VisitBinding(I.getData());
2544
1.51M
  }
2545
1.22M
}
2546
2547
1.51M
void RemoveDeadBindingsWorker::VisitBinding(SVal V) {
2548
  // Is it a LazyCompoundVal?  All referenced regions are live as well.
2549
1.51M
  if (Optional<nonloc::LazyCompoundVal> LCS =
2550
4.43k
          V.getAs<nonloc::LazyCompoundVal>()) {
2551
2552
4.43k
    const RegionStoreManager::SValListTy &Vals = RM.getInterestingValues(*LCS);
2553
2554
4.43k
    for (RegionStoreManager::SValListTy::const_iterator I = Vals.begin(),
2555
4.43k
                                                        E = Vals.end();
2556
4.82k
         I != E; 
++I390
)
2557
390
      VisitBinding(*I);
2558
2559
4.43k
    return;
2560
4.43k
  }
2561
2562
  // If V is a region, then add it to the worklist.
2563
1.51M
  if (const MemRegion *R = V.getAsRegion()) {
2564
388k
    AddToWorkList(R);
2565
388k
    SymReaper.markLive(R);
2566
2567
    // All regions captured by a block are also live.
2568
388k
    if (const BlockDataRegion *BR = dyn_cast<BlockDataRegion>(R)) {
2569
624
      BlockDataRegion::referenced_vars_iterator I = BR->referenced_vars_begin(),
2570
624
                                                E = BR->referenced_vars_end();
2571
1.18k
      for ( ; I != E; 
++I563
)
2572
563
        AddToWorkList(I.getCapturedRegion());
2573
624
    }
2574
388k
  }
2575
2576
2577
  // Update the set of live symbols.
2578
2.38M
  for (auto SI = V.symbol_begin(), SE = V.symbol_end(); SI!=SE; 
++SI869k
)
2579
869k
    SymReaper.markLive(*SI);
2580
1.51M
}
2581
2582
362k
bool RemoveDeadBindingsWorker::UpdatePostponed() {
2583
  // See if any postponed SymbolicRegions are actually live now, after
2584
  // having done a scan.
2585
362k
  bool Changed = false;
2586
2587
377k
  for (auto I = Postponed.begin(), E = Postponed.end(); I != E; 
++I14.8k
) {
2588
14.8k
    if (const SymbolicRegion *SR = *I) {
2589
12.6k
      if (SymReaper.isLive(SR->getSymbol())) {
2590
5.43k
        Changed |= AddToWorkList(SR);
2591
5.43k
        *I = nullptr;
2592
5.43k
      }
2593
12.6k
    }
2594
14.8k
  }
2595
2596
362k
  return Changed;
2597
362k
}
2598
2599
StoreRef RegionStoreManager::removeDeadBindings(Store store,
2600
                                                const StackFrameContext *LCtx,
2601
361k
                                                SymbolReaper& SymReaper) {
2602
361k
  RegionBindingsRef B = getRegionBindings(store);
2603
361k
  RemoveDeadBindingsWorker W(*this, StateMgr, B, SymReaper, LCtx);
2604
361k
  W.GenerateClusters();
2605
2606
  // Enqueue the region roots onto the worklist.
2607
361k
  for (SymbolReaper::region_iterator I = SymReaper.region_begin(),
2608
1.14M
       E = SymReaper.region_end(); I != E; 
++I786k
) {
2609
786k
    W.AddToWorkList(*I);
2610
786k
  }
2611
2612
362k
  do W.RunWorkList(); while (W.UpdatePostponed());
2613
2614
  // We have now scanned the store, marking reachable regions and symbols
2615
  // as live.  We now remove all the regions that are dead from the store
2616
  // as well as update DSymbols with the set symbols that are now dead.
2617
1.69M
  for (RegionBindingsRef::iterator I = B.begin(), E = B.end(); I != E; 
++I1.33M
) {
2618
1.33M
    const MemRegion *Base = I.getKey();
2619
2620
    // If the cluster has been visited, we know the region has been marked.
2621
    // Otherwise, remove the dead entry.
2622
1.33M
    if (!W.isVisited(Base))
2623
112k
      B = B.remove(Base);
2624
1.33M
  }
2625
2626
361k
  return StoreRef(B.asStore(), *this);
2627
361k
}
2628
2629
//===----------------------------------------------------------------------===//
2630
// Utility methods.
2631
//===----------------------------------------------------------------------===//
2632
2633
void RegionStoreManager::printJson(raw_ostream &Out, Store S, const char *NL,
2634
126
                                   unsigned int Space, bool IsDot) const {
2635
126
  RegionBindingsRef Bindings = getRegionBindings(S);
2636
2637
126
  Indent(Out, Space, IsDot) << "\"store\": ";
2638
2639
126
  if (Bindings.isEmpty()) {
2640
40
    Out << "null," << NL;
2641
40
    return;
2642
40
  }
2643
2644
86
  Out << "{ \"pointer\": \"" << Bindings.asStore() << "\", \"items\": [" << NL;
2645
86
  Bindings.printJson(Out, NL, Space + 1, IsDot);
2646
86
  Indent(Out, Space, IsDot) << "]}," << NL;
2647
86
}