Coverage Report

Created: 2020-09-19 12:23

/Users/buildslave/jenkins/workspace/coverage/llvm-project/clang/lib/StaticAnalyzer/Core/Store.cpp
Line
Count
Source (jump to first uncovered line)
1
//===- Store.cpp - Interface for maps from Locations to Values ------------===//
2
//
3
// 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
//
7
//===----------------------------------------------------------------------===//
8
//
9
//  This file defined the types Store and StoreManager.
10
//
11
//===----------------------------------------------------------------------===//
12
13
#include "clang/StaticAnalyzer/Core/PathSensitive/Store.h"
14
#include "clang/AST/ASTContext.h"
15
#include "clang/AST/CXXInheritance.h"
16
#include "clang/AST/CharUnits.h"
17
#include "clang/AST/Decl.h"
18
#include "clang/AST/DeclCXX.h"
19
#include "clang/AST/DeclObjC.h"
20
#include "clang/AST/Expr.h"
21
#include "clang/AST/Type.h"
22
#include "clang/Basic/LLVM.h"
23
#include "clang/StaticAnalyzer/Core/PathSensitive/BasicValueFactory.h"
24
#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
25
#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
26
#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
27
#include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h"
28
#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
29
#include "clang/StaticAnalyzer/Core/PathSensitive/StoreRef.h"
30
#include "clang/StaticAnalyzer/Core/PathSensitive/SymExpr.h"
31
#include "llvm/ADT/APSInt.h"
32
#include "llvm/ADT/Optional.h"
33
#include "llvm/ADT/SmallVector.h"
34
#include "llvm/Support/Casting.h"
35
#include "llvm/Support/ErrorHandling.h"
36
#include <cassert>
37
#include <cstdint>
38
39
using namespace clang;
40
using namespace ento;
41
42
StoreManager::StoreManager(ProgramStateManager &stateMgr)
43
    : svalBuilder(stateMgr.getSValBuilder()), StateMgr(stateMgr),
44
13.6k
      MRMgr(svalBuilder.getRegionManager()), Ctx(stateMgr.getContext()) {}
45
46
StoreRef StoreManager::enterStackFrame(Store OldStore,
47
                                       const CallEvent &Call,
48
33.7k
                                       const StackFrameContext *LCtx) {
49
33.7k
  StoreRef Store = StoreRef(OldStore, *this);
50
33.7k
51
33.7k
  SmallVector<CallEvent::FrameBindingTy, 16> InitialBindings;
52
33.7k
  Call.getInitialStackFrameContents(LCtx, InitialBindings);
53
33.7k
54
33.7k
  for (const auto &I : InitialBindings)
55
38.9k
    Store = Bind(Store.getStore(), I.first.castAs<Loc>(), I.second);
56
33.7k
57
33.7k
  return Store;
58
33.7k
}
59
60
const ElementRegion *StoreManager::MakeElementRegion(const SubRegion *Base,
61
                                                     QualType EleTy,
62
7.11k
                                                     uint64_t index) {
63
7.11k
  NonLoc idx = svalBuilder.makeArrayIndex(index);
64
7.11k
  return MRMgr.getElementRegion(EleTy, idx, Base, svalBuilder.getContext());
65
7.11k
}
66
67
const ElementRegion *StoreManager::GetElementZeroRegion(const SubRegion *R,
68
7.87k
                                                        QualType T) {
69
7.87k
  NonLoc idx = svalBuilder.makeZeroArrayIndex();
70
7.87k
  assert(!T.isNull());
71
7.87k
  return MRMgr.getElementRegion(T, idx, R, Ctx);
72
7.87k
}
73
74
8.86k
const MemRegion *StoreManager::castRegion(const MemRegion *R, QualType CastToTy) {
75
8.86k
  ASTContext &Ctx = StateMgr.getContext();
76
8.86k
77
  // Handle casts to Objective-C objects.
78
8.86k
  if (CastToTy->isObjCObjectPointerType())
79
1.21k
    return R->StripCasts();
80
7.65k
81
7.65k
  if (CastToTy->isBlockPointerType()) {
82
    // FIXME: We may need different solutions, depending on the symbol
83
    // involved.  Blocks can be casted to/from 'id', as they can be treated
84
    // as Objective-C objects.  This could possibly be handled by enhancing
85
    // our reasoning of downcasts of symbolic objects.
86
3
    if (isa<CodeTextRegion>(R) || isa<SymbolicRegion>(R))
87
2
      return R;
88
1
89
    // We don't know what to make of it.  Return a NULL region, which
90
    // will be interpreted as UnknownVal.
91
1
    return nullptr;
92
1
  }
93
7.65k
94
  // Now assume we are casting from pointer to pointer. Other cases should
95
  // already be handled.
96
7.65k
  QualType PointeeTy = CastToTy->getPointeeType();
97
7.65k
  QualType CanonPointeeTy = Ctx.getCanonicalType(PointeeTy);
98
7.65k
99
  // Handle casts to void*.  We just pass the region through.
100
7.65k
  if (CanonPointeeTy.getLocalUnqualifiedType() == Ctx.VoidTy)
101
178
    return R;
102
7.47k
103
  // Handle casts from compatible types.
104
7.47k
  if (R->isBoundable())
105
7.47k
    if (const auto *TR = dyn_cast<TypedValueRegion>(R)) {
106
2.01k
      QualType ObjTy = Ctx.getCanonicalType(TR->getValueType());
107
2.01k
      if (CanonPointeeTy == ObjTy)
108
361
        return R;
109
7.11k
    }
110
7.11k
111
  // Process region cast according to the kind of the region being cast.
112
7.11k
  switch (R->getKind()) {
113
0
    case MemRegion::CXXThisRegionKind:
114
0
    case MemRegion::CodeSpaceRegionKind:
115
0
    case MemRegion::StackLocalsSpaceRegionKind:
116
0
    case MemRegion::StackArgumentsSpaceRegionKind:
117
0
    case MemRegion::HeapSpaceRegionKind:
118
0
    case MemRegion::UnknownSpaceRegionKind:
119
0
    case MemRegion::StaticGlobalSpaceRegionKind:
120
0
    case MemRegion::GlobalInternalSpaceRegionKind:
121
0
    case MemRegion::GlobalSystemSpaceRegionKind:
122
0
    case MemRegion::GlobalImmutableSpaceRegionKind: {
123
0
      llvm_unreachable("Invalid region cast");
124
0
    }
125
0
126
6.66k
    case MemRegion::FunctionCodeRegionKind:
127
6.66k
    case MemRegion::BlockCodeRegionKind:
128
6.66k
    case MemRegion::BlockDataRegionKind:
129
6.66k
    case MemRegion::StringRegionKind:
130
      // FIXME: Need to handle arbitrary downcasts.
131
6.66k
    case MemRegion::SymbolicRegionKind:
132
6.66k
    case MemRegion::AllocaRegionKind:
133
6.66k
    case MemRegion::CompoundLiteralRegionKind:
134
6.66k
    case MemRegion::FieldRegionKind:
135
6.66k
    case MemRegion::ObjCIvarRegionKind:
136
6.66k
    case MemRegion::ObjCStringRegionKind:
137
6.66k
    case MemRegion::NonParamVarRegionKind:
138
6.66k
    case MemRegion::ParamVarRegionKind:
139
6.66k
    case MemRegion::CXXTempObjectRegionKind:
140
6.66k
    case MemRegion::CXXBaseObjectRegionKind:
141
6.66k
    case MemRegion::CXXDerivedObjectRegionKind:
142
6.66k
      return MakeElementRegion(cast<SubRegion>(R), PointeeTy);
143
6.66k
144
450
    case MemRegion::ElementRegionKind: {
145
      // If we are casting from an ElementRegion to another type, the
146
      // algorithm is as follows:
147
      //
148
      // (1) Compute the "raw offset" of the ElementRegion from the
149
      //     base region.  This is done by calling 'getAsRawOffset()'.
150
      //
151
      // (2a) If we get a 'RegionRawOffset' after calling
152
      //      'getAsRawOffset()', determine if the absolute offset
153
      //      can be exactly divided into chunks of the size of the
154
      //      casted-pointee type.  If so, create a new ElementRegion with
155
      //      the pointee-cast type as the new ElementType and the index
156
      //      being the offset divded by the chunk size.  If not, create
157
      //      a new ElementRegion at offset 0 off the raw offset region.
158
      //
159
      // (2b) If we don't a get a 'RegionRawOffset' after calling
160
      //      'getAsRawOffset()', it means that we are at offset 0.
161
      //
162
      // FIXME: Handle symbolic raw offsets.
163
450
164
450
      const ElementRegion *elementR = cast<ElementRegion>(R);
165
450
      const RegionRawOffset &rawOff = elementR->getAsArrayOffset();
166
450
      const MemRegion *baseR = rawOff.getRegion();
167
450
168
      // If we cannot compute a raw offset, throw up our hands and return
169
      // a NULL MemRegion*.
170
450
      if (!baseR)
171
13
        return nullptr;
172
437
173
437
      CharUnits off = rawOff.getOffset();
174
437
175
437
      if (off.isZero()) {
176
        // Edge case: we are at 0 bytes off the beginning of baseR.  We
177
        // check to see if type we are casting to is the same as the base
178
        // region.  If so, just return the base region.
179
178
        if (const auto *TR = dyn_cast<TypedValueRegion>(baseR)) {
180
101
          QualType ObjTy = Ctx.getCanonicalType(TR->getValueType());
181
101
          QualType CanonPointeeTy = Ctx.getCanonicalType(PointeeTy);
182
101
          if (CanonPointeeTy == ObjTy)
183
6
            return baseR;
184
172
        }
185
172
186
        // Otherwise, create a new ElementRegion at offset 0.
187
172
        return MakeElementRegion(cast<SubRegion>(baseR), PointeeTy);
188
172
      }
189
259
190
      // We have a non-zero offset from the base region.  We want to determine
191
      // if the offset can be evenly divided by sizeof(PointeeTy).  If so,
192
      // we create an ElementRegion whose index is that value.  Otherwise, we
193
      // create two ElementRegions, one that reflects a raw offset and the other
194
      // that reflects the cast.
195
259
196
      // Compute the index for the new ElementRegion.
197
259
      int64_t newIndex = 0;
198
259
      const MemRegion *newSuperR = nullptr;
199
259
200
      // We can only compute sizeof(PointeeTy) if it is a complete type.
201
259
      if (!PointeeTy->isIncompleteType()) {
202
        // Compute the size in **bytes**.
203
257
        CharUnits pointeeTySize = Ctx.getTypeSizeInChars(PointeeTy);
204
257
        if (!pointeeTySize.isZero()) {
205
          // Is the offset a multiple of the size?  If so, we can layer the
206
          // ElementRegion (with elementType == PointeeTy) directly on top of
207
          // the base region.
208
255
          if (off % pointeeTySize == 0) {
209
237
            newIndex = off / pointeeTySize;
210
237
            newSuperR = baseR;
211
237
          }
212
255
        }
213
257
      }
214
259
215
259
      if (!newSuperR) {
216
        // Create an intermediate ElementRegion to represent the raw byte.
217
        // This will be the super region of the final ElementRegion.
218
22
        newSuperR = MakeElementRegion(cast<SubRegion>(baseR), Ctx.CharTy,
219
22
                                      off.getQuantity());
220
22
      }
221
259
222
259
      return MakeElementRegion(cast<SubRegion>(newSuperR), PointeeTy, newIndex);
223
259
    }
224
0
  }
225
0
226
0
  llvm_unreachable("unreachable");
227
0
}
228
229
834
static bool regionMatchesCXXRecordType(SVal V, QualType Ty) {
230
834
  const MemRegion *MR = V.getAsRegion();
231
834
  if (!MR)
232
7
    return true;
233
827
234
827
  const auto *TVR = dyn_cast<TypedValueRegion>(MR);
235
827
  if (!TVR)
236
234
    return true;
237
593
238
593
  const CXXRecordDecl *RD = TVR->getValueType()->getAsCXXRecordDecl();
239
593
  if (!RD)
240
0
    return true;
241
593
242
593
  const CXXRecordDecl *Expected = Ty->getPointeeCXXRecordDecl();
243
593
  if (!Expected)
244
428
    Expected = Ty->getAsCXXRecordDecl();
245
593
246
593
  return Expected->getCanonicalDecl() == RD->getCanonicalDecl();
247
593
}
248
249
834
SVal StoreManager::evalDerivedToBase(SVal Derived, const CastExpr *Cast) {
250
  // Sanity check to avoid doing the wrong thing in the face of
251
  // reinterpret_cast.
252
834
  if (!regionMatchesCXXRecordType(Derived, Cast->getSubExpr()->getType()))
253
1
    return UnknownVal();
254
833
255
  // Walk through the cast path to create nested CXXBaseRegions.
256
833
  SVal Result = Derived;
257
833
  for (CastExpr::path_const_iterator I = Cast->path_begin(),
258
833
                                     E = Cast->path_end();
259
1.76k
       I != E; 
++I930
) {
260
930
    Result = evalDerivedToBase(Result, (*I)->getType(), (*I)->isVirtual());
261
930
  }
262
833
  return Result;
263
833
}
264
265
10
SVal StoreManager::evalDerivedToBase(SVal Derived, const CXXBasePath &Path) {
266
  // Walk through the path to create nested CXXBaseRegions.
267
10
  SVal Result = Derived;
268
10
  for (const auto &I : Path)
269
12
    Result = evalDerivedToBase(Result, I.Base->getType(),
270
12
                               I.Base->isVirtual());
271
10
  return Result;
272
10
}
273
274
SVal StoreManager::evalDerivedToBase(SVal Derived, QualType BaseType,
275
1.82k
                                     bool IsVirtual) {
276
1.82k
  const MemRegion *DerivedReg = Derived.getAsRegion();
277
1.82k
  if (!DerivedReg)
278
11
    return Derived;
279
1.81k
280
1.81k
  const CXXRecordDecl *BaseDecl = BaseType->getPointeeCXXRecordDecl();
281
1.81k
  if (!BaseDecl)
282
1.81k
    BaseDecl = BaseType->getAsCXXRecordDecl();
283
1.81k
  assert(BaseDecl && "not a C++ object?");
284
1.81k
285
1.81k
  if (const auto *AlreadyDerivedReg =
286
13
          dyn_cast<CXXDerivedObjectRegion>(DerivedReg)) {
287
13
    if (const auto *SR =
288
13
            dyn_cast<SymbolicRegion>(AlreadyDerivedReg->getSuperRegion()))
289
13
      if (SR->getSymbol()->getType()->getPointeeCXXRecordDecl() == BaseDecl)
290
10
        return loc::MemRegionVal(SR);
291
3
292
3
    DerivedReg = AlreadyDerivedReg->getSuperRegion();
293
3
  }
294
1.81k
295
1.80k
  const MemRegion *BaseReg = MRMgr.getCXXBaseObjectRegion(
296
1.80k
      BaseDecl, cast<SubRegion>(DerivedReg), IsVirtual);
297
1.80k
298
1.80k
  return loc::MemRegionVal(BaseReg);
299
1.81k
}
300
301
/// Returns the static type of the given region, if it represents a C++ class
302
/// object.
303
///
304
/// This handles both fully-typed regions, where the dynamic type is known, and
305
/// symbolic regions, where the dynamic type is merely bounded (and even then,
306
/// only ostensibly!), but does not take advantage of any dynamic type info.
307
262
static const CXXRecordDecl *getCXXRecordType(const MemRegion *MR) {
308
262
  if (const auto *TVR = dyn_cast<TypedValueRegion>(MR))
309
174
    return TVR->getValueType()->getAsCXXRecordDecl();
310
88
  if (const auto *SR = dyn_cast<SymbolicRegion>(MR))
311
88
    return SR->getSymbol()->getType()->getPointeeCXXRecordDecl();
312
0
  return nullptr;
313
0
}
314
315
SVal StoreManager::attemptDownCast(SVal Base, QualType TargetType,
316
139
                                   bool &Failed) {
317
139
  Failed = false;
318
139
319
139
  const MemRegion *MR = Base.getAsRegion();
320
139
  if (!MR)
321
0
    return UnknownVal();
322
139
323
  // Assume the derived class is a pointer or a reference to a CXX record.
324
139
  TargetType = TargetType->getPointeeType();
325
139
  assert(!TargetType.isNull());
326
139
  const CXXRecordDecl *TargetClass = TargetType->getAsCXXRecordDecl();
327
139
  if (!TargetClass && 
!TargetType->isVoidType()1
)
328
0
    return UnknownVal();
329
139
330
  // Drill down the CXXBaseObject chains, which represent upcasts (casts from
331
  // derived to base).
332
262
  
while (const CXXRecordDecl *139
MRClass = getCXXRecordType(MR)) {
333
    // If found the derived class, the cast succeeds.
334
260
    if (MRClass == TargetClass)
335
91
      return loc::MemRegionVal(MR);
336
169
337
    // We skip over incomplete types. They must be the result of an earlier
338
    // reinterpret_cast, as one can only dynamic_cast between types in the same
339
    // class hierarchy.
340
169
    if (!TargetType->isVoidType() && 
MRClass->hasDefinition()168
) {
341
      // Static upcasts are marked as DerivedToBase casts by Sema, so this will
342
      // only happen when multiple or virtual inheritance is involved.
343
165
      CXXBasePaths Paths(/*FindAmbiguities=*/false, /*RecordPaths=*/true,
344
165
                         /*DetectVirtual=*/false);
345
165
      if (MRClass->isDerivedFrom(TargetClass, Paths))
346
9
        return evalDerivedToBase(loc::MemRegionVal(MR), Paths.front());
347
160
    }
348
160
349
160
    if (const auto *BaseR = dyn_cast<CXXBaseObjectRegion>(MR)) {
350
      // Drill down the chain to get the derived classes.
351
114
      MR = BaseR->getSuperRegion();
352
114
      continue;
353
114
    }
354
46
355
    // If this is a cast to void*, return the region.
356
46
    if (TargetType->isVoidType())
357
1
      return loc::MemRegionVal(MR);
358
45
359
    // Strange use of reinterpret_cast can give us paths we don't reason
360
    // about well, by putting in ElementRegions where we'd expect
361
    // CXXBaseObjectRegions. If it's a valid reinterpret_cast (i.e. if the
362
    // derived class has a zero offset from the base class), then it's safe
363
    // to strip the cast; if it's invalid, -Wreinterpret-base-class should
364
    // catch it. In the interest of performance, the analyzer will silently
365
    // do the wrong thing in the invalid case (because offsets for subregions
366
    // will be wrong).
367
45
    const MemRegion *Uncasted = MR->StripCasts(/*IncludeBaseCasts=*/false);
368
45
    if (Uncasted == MR) {
369
      // We reached the bottom of the hierarchy and did not find the derived
370
      // class. We must be casting the base to derived, so the cast should
371
      // fail.
372
36
      break;
373
36
    }
374
9
375
9
    MR = Uncasted;
376
9
  }
377
139
378
  // If we're casting a symbolic base pointer to a derived class, use
379
  // CXXDerivedObjectRegion to represent the cast. If it's a pointer to an
380
  // unrelated type, it must be a weird reinterpret_cast and we have to
381
  // be fine with ElementRegion. TODO: Should we instead make
382
  // Derived{TargetClass, Element{SourceClass, SR}}?
383
38
  if (const auto *SR = dyn_cast<SymbolicRegion>(MR)) {
384
26
    QualType T = SR->getSymbol()->getType();
385
26
    const CXXRecordDecl *SourceClass = T->getPointeeCXXRecordDecl();
386
26
    if (TargetClass && SourceClass && 
TargetClass->isDerivedFrom(SourceClass)25
)
387
21
      return loc::MemRegionVal(
388
21
          MRMgr.getCXXDerivedObjectRegion(TargetClass, SR));
389
5
    return loc::MemRegionVal(GetElementZeroRegion(SR, TargetType));
390
5
  }
391
12
392
  // We failed if the region we ended up with has perfect type info.
393
12
  Failed = isa<TypedValueRegion>(MR);
394
12
  return UnknownVal();
395
12
}
396
397
44.1k
static bool hasSameUnqualifiedPointeeType(QualType ty1, QualType ty2) {
398
44.1k
  return ty1->getPointeeType().getCanonicalType().getTypePtr() ==
399
44.1k
         ty2->getPointeeType().getCanonicalType().getTypePtr();
400
44.1k
}
401
402
/// CastRetrievedVal - Used by subclasses of StoreManager to implement
403
///  implicit casts that arise from loads from regions that are reinterpreted
404
///  as another region.
405
SVal StoreManager::CastRetrievedVal(SVal V, const TypedValueRegion *R,
406
392k
                                    QualType castTy) {
407
392k
  if (castTy.isNull() || V.isUnknownOrUndef())
408
83.4k
    return V;
409
309k
410
  // The dispatchCast() call below would convert the int into a float.
411
  // What we want, however, is a bit-by-bit reinterpretation of the int
412
  // as a float, which usually yields nothing garbage. For now skip casts
413
  // from ints to floats.
414
  // TODO: What other combinations of types are affected?
415
309k
  if (castTy->isFloatingType()) {
416
89
    SymbolRef Sym = V.getAsSymbol();
417
89
    if (Sym && 
!Sym->getType()->isFloatingType()73
)
418
25
      return UnknownVal();
419
309k
  }
420
309k
421
  // When retrieving symbolic pointer and expecting a non-void pointer,
422
  // wrap them into element regions of the expected type if necessary.
423
  // SValBuilder::dispatchCast() doesn't do that, but it is necessary to
424
  // make sure that the retrieved value makes sense, because there's no other
425
  // cast in the AST that would tell us to cast it to the correct pointer type.
426
  // We might need to do that for non-void pointers as well.
427
  // FIXME: We really need a single good function to perform casts for us
428
  // correctly every time we need it.
429
309k
  if (castTy->isPointerType() && 
!castTy->isVoidPointerType()149k
)
430
142k
    if (const auto *SR = dyn_cast_or_null<SymbolicRegion>(V.getAsRegion())) {
431
44.1k
      QualType sr = SR->getSymbol()->getType();
432
44.1k
      if (!hasSameUnqualifiedPointeeType(sr, castTy))
433
13
          return loc::MemRegionVal(castRegion(SR, castTy));
434
309k
    }
435
309k
436
309k
  return svalBuilder.dispatchCast(V, castTy);
437
309k
}
438
439
55.0k
SVal StoreManager::getLValueFieldOrIvar(const Decl *D, SVal Base) {
440
55.0k
  if (Base.isUnknownOrUndef())
441
11
    return Base;
442
55.0k
443
55.0k
  Loc BaseL = Base.castAs<Loc>();
444
55.0k
  const SubRegion* BaseR = nullptr;
445
55.0k
446
55.0k
  switch (BaseL.getSubKind()) {
447
55.0k
  case loc::MemRegionValKind:
448
55.0k
    BaseR = cast<SubRegion>(BaseL.castAs<loc::MemRegionVal>().getRegion());
449
55.0k
    break;
450
0
451
0
  case loc::GotoLabelKind:
452
    // These are anormal cases. Flag an undefined value.
453
0
    return UndefinedVal();
454
0
455
64
  case loc::ConcreteIntKind:
456
    // While these seem funny, this can happen through casts.
457
    // FIXME: What we should return is the field offset, not base. For example,
458
    //  add the field offset to the integer value.  That way things
459
    //  like this work properly:  &(((struct foo *) 0xa)->f)
460
    //  However, that's not easy to fix without reducing our abilities
461
    //  to catch null pointer dereference. Eg., ((struct foo *)0x0)->f = 7
462
    //  is a null dereference even though we're dereferencing offset of f
463
    //  rather than null. Coming up with an approach that computes offsets
464
    //  over null pointers properly while still being able to catch null
465
    //  dereferences might be worth it.
466
64
    return Base;
467
0
468
0
  default:
469
0
    llvm_unreachable("Unhandled Base.");
470
55.0k
  }
471
55.0k
472
  // NOTE: We must have this check first because ObjCIvarDecl is a subclass
473
  // of FieldDecl.
474
55.0k
  if (const auto *ID = dyn_cast<ObjCIvarDecl>(D))
475
1.45k
    return loc::MemRegionVal(MRMgr.getObjCIvarRegion(ID, BaseR));
476
53.5k
477
53.5k
  return loc::MemRegionVal(MRMgr.getFieldRegion(cast<FieldDecl>(D), BaseR));
478
53.5k
}
479
480
1.47k
SVal StoreManager::getLValueIvar(const ObjCIvarDecl *decl, SVal base) {
481
1.47k
  return getLValueFieldOrIvar(decl, base);
482
1.47k
}
483
484
SVal StoreManager::getLValueElement(QualType elementType, NonLoc Offset,
485
7.95k
                                    SVal Base) {
486
  // If the base is an unknown or undefined value, just return it back.
487
  // FIXME: For absolute pointer addresses, we just return that value back as
488
  //  well, although in reality we should return the offset added to that
489
  //  value. See also the similar FIXME in getLValueFieldOrIvar().
490
7.95k
  if (Base.isUnknownOrUndef() || 
Base.getAs<loc::ConcreteInt>()7.94k
)
491
68
    return Base;
492
7.88k
493
7.88k
  if (Base.getAs<loc::GotoLabel>())
494
2
    return UnknownVal();
495
7.88k
496
7.88k
  const SubRegion *BaseRegion =
497
7.88k
      Base.castAs<loc::MemRegionVal>().getRegionAs<SubRegion>();
498
7.88k
499
  // Pointer of any type can be cast and used as array base.
500
7.88k
  const auto *ElemR = dyn_cast<ElementRegion>(BaseRegion);
501
7.88k
502
  // Convert the offset to the appropriate size and signedness.
503
7.88k
  Offset = svalBuilder.convertToArrayIndex(Offset).castAs<NonLoc>();
504
7.88k
505
7.88k
  if (!ElemR) {
506
    // If the base region is not an ElementRegion, create one.
507
    // This can happen in the following example:
508
    //
509
    //   char *p = __builtin_alloc(10);
510
    //   p[1] = 8;
511
    //
512
    //  Observe that 'p' binds to an AllocaRegion.
513
2.31k
    return loc::MemRegionVal(MRMgr.getElementRegion(elementType, Offset,
514
2.31k
                                                    BaseRegion, Ctx));
515
2.31k
  }
516
5.57k
517
5.57k
  SVal BaseIdx = ElemR->getIndex();
518
5.57k
519
5.57k
  if (!BaseIdx.getAs<nonloc::ConcreteInt>())
520
32
    return UnknownVal();
521
5.53k
522
5.53k
  const llvm::APSInt &BaseIdxI =
523
5.53k
      BaseIdx.castAs<nonloc::ConcreteInt>().getValue();
524
5.53k
525
  // Only allow non-integer offsets if the base region has no offset itself.
526
  // FIXME: This is a somewhat arbitrary restriction. We should be using
527
  // SValBuilder here to add the two offsets without checking their types.
528
5.53k
  if (!Offset.getAs<nonloc::ConcreteInt>()) {
529
290
    if (isa<ElementRegion>(BaseRegion->StripCasts()))
530
0
      return UnknownVal();
531
290
532
290
    return loc::MemRegionVal(MRMgr.getElementRegion(
533
290
        elementType, Offset, cast<SubRegion>(ElemR->getSuperRegion()), Ctx));
534
290
  }
535
5.24k
536
5.24k
  const llvm::APSInt& OffI = Offset.castAs<nonloc::ConcreteInt>().getValue();
537
5.24k
  assert(BaseIdxI.isSigned());
538
5.24k
539
  // Compute the new index.
540
5.24k
  nonloc::ConcreteInt NewIdx(svalBuilder.getBasicValueFactory().getValue(BaseIdxI +
541
5.24k
                                                                    OffI));
542
5.24k
543
  // Construct the new ElementRegion.
544
5.24k
  const SubRegion *ArrayR = cast<SubRegion>(ElemR->getSuperRegion());
545
5.24k
  return loc::MemRegionVal(MRMgr.getElementRegion(elementType, NewIdx, ArrayR,
546
5.24k
                                                  Ctx));
547
5.24k
}
548
549
77.1k
StoreManager::BindingsHandler::~BindingsHandler() = default;
550
551
bool StoreManager::FindUniqueBinding::HandleBinding(StoreManager& SMgr,
552
                                                    Store store,
553
                                                    const MemRegion* R,
554
26.4k
                                                    SVal val) {
555
26.4k
  SymbolRef SymV = val.getAsLocSymbol();
556
26.4k
  if (!SymV || 
SymV != Sym15.9k
)
557
16.2k
    return true;
558
10.2k
559
10.2k
  if (Binding) {
560
544
    First = false;
561
544
    return false;
562
544
  }
563
9.70k
  else
564
9.70k
    Binding = R;
565
10.2k
566
9.70k
  return true;
567
10.2k
}