Deleted Added
sdiff udiff text old ( 218893 ) new ( 226633 )
full compact
SymbolManager.cpp (218893) SymbolManager.cpp (226633)
1//== SymbolManager.h - Management of Symbolic Values ------------*- C++ -*--==//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines SymbolManager, a class that manages symbolic values
11// created for use by ExprEngine and related classes.
12//
13//===----------------------------------------------------------------------===//
14
15#include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h"
16#include "clang/Analysis/Analyses/LiveVariables.h"
17#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
1//== SymbolManager.h - Management of Symbolic Values ------------*- C++ -*--==//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines SymbolManager, a class that manages symbolic values
11// created for use by ExprEngine and related classes.
12//
13//===----------------------------------------------------------------------===//
14
15#include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h"
16#include "clang/Analysis/Analyses/LiveVariables.h"
17#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
18#include "clang/StaticAnalyzer/Core/PathSensitive/Store.h"
18#include "llvm/Support/raw_ostream.h"
19
20using namespace clang;
21using namespace ento;
22
23void SymExpr::dump() const {
24 dumpToStream(llvm::errs());
25}
26
19#include "llvm/Support/raw_ostream.h"
20
21using namespace clang;
22using namespace ento;
23
24void SymExpr::dump() const {
25 dumpToStream(llvm::errs());
26}
27
27static void print(llvm::raw_ostream& os, BinaryOperator::Opcode Op) {
28static void print(raw_ostream &os, BinaryOperator::Opcode Op) {
28 switch (Op) {
29 default:
29 switch (Op) {
30 default:
30 assert(false && "operator printing not implemented");
31 break;
31 llvm_unreachable("operator printing not implemented");
32 case BO_Mul: os << '*' ; break;
33 case BO_Div: os << '/' ; break;
34 case BO_Rem: os << '%' ; break;
35 case BO_Add: os << '+' ; break;
36 case BO_Sub: os << '-' ; break;
37 case BO_Shl: os << "<<" ; break;
38 case BO_Shr: os << ">>" ; break;
39 case BO_LT: os << "<" ; break;
40 case BO_GT: os << '>' ; break;
41 case BO_LE: os << "<=" ; break;
42 case BO_GE: os << ">=" ; break;
43 case BO_EQ: os << "==" ; break;
44 case BO_NE: os << "!=" ; break;
45 case BO_And: os << '&' ; break;
46 case BO_Xor: os << '^' ; break;
47 case BO_Or: os << '|' ; break;
48 }
49}
50
32 case BO_Mul: os << '*' ; break;
33 case BO_Div: os << '/' ; break;
34 case BO_Rem: os << '%' ; break;
35 case BO_Add: os << '+' ; break;
36 case BO_Sub: os << '-' ; break;
37 case BO_Shl: os << "<<" ; break;
38 case BO_Shr: os << ">>" ; break;
39 case BO_LT: os << "<" ; break;
40 case BO_GT: os << '>' ; break;
41 case BO_LE: os << "<=" ; break;
42 case BO_GE: os << ">=" ; break;
43 case BO_EQ: os << "==" ; break;
44 case BO_NE: os << "!=" ; break;
45 case BO_And: os << '&' ; break;
46 case BO_Xor: os << '^' ; break;
47 case BO_Or: os << '|' ; break;
48 }
49}
50
51void SymIntExpr::dumpToStream(llvm::raw_ostream& os) const {
51void SymIntExpr::dumpToStream(raw_ostream &os) const {
52 os << '(';
53 getLHS()->dumpToStream(os);
54 os << ") ";
55 print(os, getOpcode());
56 os << ' ' << getRHS().getZExtValue();
57 if (getRHS().isUnsigned()) os << 'U';
58}
59
52 os << '(';
53 getLHS()->dumpToStream(os);
54 os << ") ";
55 print(os, getOpcode());
56 os << ' ' << getRHS().getZExtValue();
57 if (getRHS().isUnsigned()) os << 'U';
58}
59
60void SymSymExpr::dumpToStream(llvm::raw_ostream& os) const {
60void SymSymExpr::dumpToStream(raw_ostream &os) const {
61 os << '(';
62 getLHS()->dumpToStream(os);
63 os << ") ";
64 os << '(';
65 getRHS()->dumpToStream(os);
66 os << ')';
67}
68
61 os << '(';
62 getLHS()->dumpToStream(os);
63 os << ") ";
64 os << '(';
65 getRHS()->dumpToStream(os);
66 os << ')';
67}
68
69void SymbolConjured::dumpToStream(llvm::raw_ostream& os) const {
69void SymbolConjured::dumpToStream(raw_ostream &os) const {
70 os << "conj_$" << getSymbolID() << '{' << T.getAsString() << '}';
71}
72
70 os << "conj_$" << getSymbolID() << '{' << T.getAsString() << '}';
71}
72
73void SymbolDerived::dumpToStream(llvm::raw_ostream& os) const {
73void SymbolDerived::dumpToStream(raw_ostream &os) const {
74 os << "derived_$" << getSymbolID() << '{'
75 << getParentSymbol() << ',' << getRegion() << '}';
76}
77
74 os << "derived_$" << getSymbolID() << '{'
75 << getParentSymbol() << ',' << getRegion() << '}';
76}
77
78void SymbolExtent::dumpToStream(llvm::raw_ostream& os) const {
78void SymbolExtent::dumpToStream(raw_ostream &os) const {
79 os << "extent_$" << getSymbolID() << '{' << getRegion() << '}';
80}
81
79 os << "extent_$" << getSymbolID() << '{' << getRegion() << '}';
80}
81
82void SymbolMetadata::dumpToStream(llvm::raw_ostream& os) const {
82void SymbolMetadata::dumpToStream(raw_ostream &os) const {
83 os << "meta_$" << getSymbolID() << '{'
84 << getRegion() << ',' << T.getAsString() << '}';
85}
86
83 os << "meta_$" << getSymbolID() << '{'
84 << getRegion() << ',' << T.getAsString() << '}';
85}
86
87void SymbolRegionValue::dumpToStream(llvm::raw_ostream& os) const {
87void SymbolRegionValue::dumpToStream(raw_ostream &os) const {
88 os << "reg_$" << getSymbolID() << "<" << R << ">";
89}
90
91const SymbolRegionValue*
88 os << "reg_$" << getSymbolID() << "<" << R << ">";
89}
90
91const SymbolRegionValue*
92SymbolManager::getRegionValueSymbol(const TypedRegion* R) {
92SymbolManager::getRegionValueSymbol(const TypedValueRegion* R) {
93 llvm::FoldingSetNodeID profile;
94 SymbolRegionValue::Profile(profile, R);
93 llvm::FoldingSetNodeID profile;
94 SymbolRegionValue::Profile(profile, R);
95 void* InsertPos;
95 void *InsertPos;
96 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
97 if (!SD) {
98 SD = (SymExpr*) BPAlloc.Allocate<SymbolRegionValue>();
99 new (SD) SymbolRegionValue(SymbolCounter, R);
100 DataSet.InsertNode(SD, InsertPos);
101 ++SymbolCounter;
102 }
103
104 return cast<SymbolRegionValue>(SD);
105}
106
107const SymbolConjured*
96 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
97 if (!SD) {
98 SD = (SymExpr*) BPAlloc.Allocate<SymbolRegionValue>();
99 new (SD) SymbolRegionValue(SymbolCounter, R);
100 DataSet.InsertNode(SD, InsertPos);
101 ++SymbolCounter;
102 }
103
104 return cast<SymbolRegionValue>(SD);
105}
106
107const SymbolConjured*
108SymbolManager::getConjuredSymbol(const Stmt* E, QualType T, unsigned Count,
109 const void* SymbolTag) {
108SymbolManager::getConjuredSymbol(const Stmt *E, QualType T, unsigned Count,
109 const void *SymbolTag) {
110
111 llvm::FoldingSetNodeID profile;
112 SymbolConjured::Profile(profile, E, T, Count, SymbolTag);
110
111 llvm::FoldingSetNodeID profile;
112 SymbolConjured::Profile(profile, E, T, Count, SymbolTag);
113 void* InsertPos;
113 void *InsertPos;
114 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
115 if (!SD) {
116 SD = (SymExpr*) BPAlloc.Allocate<SymbolConjured>();
117 new (SD) SymbolConjured(SymbolCounter, E, T, Count, SymbolTag);
118 DataSet.InsertNode(SD, InsertPos);
119 ++SymbolCounter;
120 }
121
122 return cast<SymbolConjured>(SD);
123}
124
125const SymbolDerived*
126SymbolManager::getDerivedSymbol(SymbolRef parentSymbol,
114 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
115 if (!SD) {
116 SD = (SymExpr*) BPAlloc.Allocate<SymbolConjured>();
117 new (SD) SymbolConjured(SymbolCounter, E, T, Count, SymbolTag);
118 DataSet.InsertNode(SD, InsertPos);
119 ++SymbolCounter;
120 }
121
122 return cast<SymbolConjured>(SD);
123}
124
125const SymbolDerived*
126SymbolManager::getDerivedSymbol(SymbolRef parentSymbol,
127 const TypedRegion *R) {
127 const TypedValueRegion *R) {
128
129 llvm::FoldingSetNodeID profile;
130 SymbolDerived::Profile(profile, parentSymbol, R);
128
129 llvm::FoldingSetNodeID profile;
130 SymbolDerived::Profile(profile, parentSymbol, R);
131 void* InsertPos;
131 void *InsertPos;
132 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
133 if (!SD) {
134 SD = (SymExpr*) BPAlloc.Allocate<SymbolDerived>();
135 new (SD) SymbolDerived(SymbolCounter, parentSymbol, R);
136 DataSet.InsertNode(SD, InsertPos);
137 ++SymbolCounter;
138 }
139
140 return cast<SymbolDerived>(SD);
141}
142
143const SymbolExtent*
144SymbolManager::getExtentSymbol(const SubRegion *R) {
145 llvm::FoldingSetNodeID profile;
146 SymbolExtent::Profile(profile, R);
132 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
133 if (!SD) {
134 SD = (SymExpr*) BPAlloc.Allocate<SymbolDerived>();
135 new (SD) SymbolDerived(SymbolCounter, parentSymbol, R);
136 DataSet.InsertNode(SD, InsertPos);
137 ++SymbolCounter;
138 }
139
140 return cast<SymbolDerived>(SD);
141}
142
143const SymbolExtent*
144SymbolManager::getExtentSymbol(const SubRegion *R) {
145 llvm::FoldingSetNodeID profile;
146 SymbolExtent::Profile(profile, R);
147 void* InsertPos;
147 void *InsertPos;
148 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
149 if (!SD) {
150 SD = (SymExpr*) BPAlloc.Allocate<SymbolExtent>();
151 new (SD) SymbolExtent(SymbolCounter, R);
152 DataSet.InsertNode(SD, InsertPos);
153 ++SymbolCounter;
154 }
155
156 return cast<SymbolExtent>(SD);
157}
158
159const SymbolMetadata*
148 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
149 if (!SD) {
150 SD = (SymExpr*) BPAlloc.Allocate<SymbolExtent>();
151 new (SD) SymbolExtent(SymbolCounter, R);
152 DataSet.InsertNode(SD, InsertPos);
153 ++SymbolCounter;
154 }
155
156 return cast<SymbolExtent>(SD);
157}
158
159const SymbolMetadata*
160SymbolManager::getMetadataSymbol(const MemRegion* R, const Stmt* S, QualType T,
161 unsigned Count, const void* SymbolTag) {
160SymbolManager::getMetadataSymbol(const MemRegion* R, const Stmt *S, QualType T,
161 unsigned Count, const void *SymbolTag) {
162
163 llvm::FoldingSetNodeID profile;
164 SymbolMetadata::Profile(profile, R, S, T, Count, SymbolTag);
162
163 llvm::FoldingSetNodeID profile;
164 SymbolMetadata::Profile(profile, R, S, T, Count, SymbolTag);
165 void* InsertPos;
165 void *InsertPos;
166 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
167 if (!SD) {
168 SD = (SymExpr*) BPAlloc.Allocate<SymbolMetadata>();
169 new (SD) SymbolMetadata(SymbolCounter, R, S, T, Count, SymbolTag);
170 DataSet.InsertNode(SD, InsertPos);
171 ++SymbolCounter;
172 }
173

--- 35 unchanged lines hidden (view full) ---

209
210 return cast<SymSymExpr>(data);
211}
212
213QualType SymbolConjured::getType(ASTContext&) const {
214 return T;
215}
216
166 SymExpr *SD = DataSet.FindNodeOrInsertPos(profile, InsertPos);
167 if (!SD) {
168 SD = (SymExpr*) BPAlloc.Allocate<SymbolMetadata>();
169 new (SD) SymbolMetadata(SymbolCounter, R, S, T, Count, SymbolTag);
170 DataSet.InsertNode(SD, InsertPos);
171 ++SymbolCounter;
172 }
173

--- 35 unchanged lines hidden (view full) ---

209
210 return cast<SymSymExpr>(data);
211}
212
213QualType SymbolConjured::getType(ASTContext&) const {
214 return T;
215}
216
217QualType SymbolDerived::getType(ASTContext& Ctx) const {
217QualType SymbolDerived::getType(ASTContext &Ctx) const {
218 return R->getValueType();
219}
220
218 return R->getValueType();
219}
220
221QualType SymbolExtent::getType(ASTContext& Ctx) const {
221QualType SymbolExtent::getType(ASTContext &Ctx) const {
222 return Ctx.getSizeType();
223}
224
225QualType SymbolMetadata::getType(ASTContext&) const {
226 return T;
227}
228
222 return Ctx.getSizeType();
223}
224
225QualType SymbolMetadata::getType(ASTContext&) const {
226 return T;
227}
228
229QualType SymbolRegionValue::getType(ASTContext& C) const {
229QualType SymbolRegionValue::getType(ASTContext &C) const {
230 return R->getValueType();
231}
232
230 return R->getValueType();
231}
232
233SymbolManager::~SymbolManager() {}
233SymbolManager::~SymbolManager() {
234 for (SymbolDependTy::const_iterator I = SymbolDependencies.begin(),
235 E = SymbolDependencies.end(); I != E; ++I) {
236 delete I->second;
237 }
234
238
239}
240
235bool SymbolManager::canSymbolicate(QualType T) {
236 T = T.getCanonicalType();
237
238 if (Loc::isLocType(T))
239 return true;
240
241 if (T->isIntegerType())
242 return T->isScalarType();
243
244 if (T->isRecordType() && !T->isUnionType())
245 return true;
246
247 return false;
248}
249
241bool SymbolManager::canSymbolicate(QualType T) {
242 T = T.getCanonicalType();
243
244 if (Loc::isLocType(T))
245 return true;
246
247 if (T->isIntegerType())
248 return T->isScalarType();
249
250 if (T->isRecordType() && !T->isUnionType())
251 return true;
252
253 return false;
254}
255
256void SymbolManager::addSymbolDependency(const SymbolRef Primary,
257 const SymbolRef Dependent) {
258 SymbolDependTy::iterator I = SymbolDependencies.find(Primary);
259 SymbolRefSmallVectorTy *dependencies = 0;
260 if (I == SymbolDependencies.end()) {
261 dependencies = new SymbolRefSmallVectorTy();
262 SymbolDependencies[Primary] = dependencies;
263 } else {
264 dependencies = I->second;
265 }
266 dependencies->push_back(Dependent);
267}
268
269const SymbolRefSmallVectorTy *SymbolManager::getDependentSymbols(
270 const SymbolRef Primary) {
271 SymbolDependTy::const_iterator I = SymbolDependencies.find(Primary);
272 if (I == SymbolDependencies.end())
273 return 0;
274 return I->second;
275}
276
277void SymbolReaper::markDependentsLive(SymbolRef sym) {
278 // Do not mark dependents more then once.
279 SymbolMapTy::iterator LI = TheLiving.find(sym);
280 assert(LI != TheLiving.end() && "The primary symbol is not live.");
281 if (LI->second == HaveMarkedDependents)
282 return;
283 LI->second = HaveMarkedDependents;
284
285 if (const SymbolRefSmallVectorTy *Deps = SymMgr.getDependentSymbols(sym)) {
286 for (SymbolRefSmallVectorTy::const_iterator I = Deps->begin(),
287 E = Deps->end(); I != E; ++I) {
288 if (TheLiving.find(*I) != TheLiving.end())
289 continue;
290 markLive(*I);
291 }
292 }
293}
294
250void SymbolReaper::markLive(SymbolRef sym) {
295void SymbolReaper::markLive(SymbolRef sym) {
251 TheLiving.insert(sym);
296 TheLiving[sym] = NotProcessed;
252 TheDead.erase(sym);
297 TheDead.erase(sym);
298 markDependentsLive(sym);
253}
254
299}
300
301void SymbolReaper::markLive(const MemRegion *region) {
302 RegionRoots.insert(region);
303}
304
255void SymbolReaper::markInUse(SymbolRef sym) {
256 if (isa<SymbolMetadata>(sym))
257 MetadataInUse.insert(sym);
258}
259
260bool SymbolReaper::maybeDead(SymbolRef sym) {
261 if (isLive(sym))
262 return false;
263
264 TheDead.insert(sym);
265 return true;
266}
267
305void SymbolReaper::markInUse(SymbolRef sym) {
306 if (isa<SymbolMetadata>(sym))
307 MetadataInUse.insert(sym);
308}
309
310bool SymbolReaper::maybeDead(SymbolRef sym) {
311 if (isLive(sym))
312 return false;
313
314 TheDead.insert(sym);
315 return true;
316}
317
268static bool IsLiveRegion(SymbolReaper &Reaper, const MemRegion *MR) {
318bool SymbolReaper::isLiveRegion(const MemRegion *MR) {
319 if (RegionRoots.count(MR))
320 return true;
321
269 MR = MR->getBaseRegion();
270
271 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(MR))
322 MR = MR->getBaseRegion();
323
324 if (const SymbolicRegion *SR = dyn_cast<SymbolicRegion>(MR))
272 return Reaper.isLive(SR->getSymbol());
325 return isLive(SR->getSymbol());
273
274 if (const VarRegion *VR = dyn_cast<VarRegion>(MR))
326
327 if (const VarRegion *VR = dyn_cast<VarRegion>(MR))
275 return Reaper.isLive(VR);
328 return isLive(VR, true);
276
277 // FIXME: This is a gross over-approximation. What we really need is a way to
278 // tell if anything still refers to this region. Unlike SymbolicRegions,
279 // AllocaRegions don't have associated symbols, though, so we don't actually
280 // have a way to track their liveness.
281 if (isa<AllocaRegion>(MR))
282 return true;
283
284 if (isa<CXXThisRegion>(MR))
285 return true;
286
287 if (isa<MemSpaceRegion>(MR))
288 return true;
289
290 return false;
291}
292
293bool SymbolReaper::isLive(SymbolRef sym) {
329
330 // FIXME: This is a gross over-approximation. What we really need is a way to
331 // tell if anything still refers to this region. Unlike SymbolicRegions,
332 // AllocaRegions don't have associated symbols, though, so we don't actually
333 // have a way to track their liveness.
334 if (isa<AllocaRegion>(MR))
335 return true;
336
337 if (isa<CXXThisRegion>(MR))
338 return true;
339
340 if (isa<MemSpaceRegion>(MR))
341 return true;
342
343 return false;
344}
345
346bool SymbolReaper::isLive(SymbolRef sym) {
294 if (TheLiving.count(sym))
347 if (TheLiving.count(sym)) {
348 markDependentsLive(sym);
295 return true;
349 return true;
350 }
296
297 if (const SymbolDerived *derived = dyn_cast<SymbolDerived>(sym)) {
298 if (isLive(derived->getParentSymbol())) {
299 markLive(sym);
300 return true;
301 }
302 return false;
303 }
304
305 if (const SymbolExtent *extent = dyn_cast<SymbolExtent>(sym)) {
351
352 if (const SymbolDerived *derived = dyn_cast<SymbolDerived>(sym)) {
353 if (isLive(derived->getParentSymbol())) {
354 markLive(sym);
355 return true;
356 }
357 return false;
358 }
359
360 if (const SymbolExtent *extent = dyn_cast<SymbolExtent>(sym)) {
306 if (IsLiveRegion(*this, extent->getRegion())) {
361 if (isLiveRegion(extent->getRegion())) {
307 markLive(sym);
308 return true;
309 }
310 return false;
311 }
312
313 if (const SymbolMetadata *metadata = dyn_cast<SymbolMetadata>(sym)) {
314 if (MetadataInUse.count(sym)) {
362 markLive(sym);
363 return true;
364 }
365 return false;
366 }
367
368 if (const SymbolMetadata *metadata = dyn_cast<SymbolMetadata>(sym)) {
369 if (MetadataInUse.count(sym)) {
315 if (IsLiveRegion(*this, metadata->getRegion())) {
370 if (isLiveRegion(metadata->getRegion())) {
316 markLive(sym);
317 MetadataInUse.erase(sym);
318 return true;
319 }
320 }
321 return false;
322 }
323
324 // Interogate the symbol. It may derive from an input value to
325 // the analyzed function/method.
326 return isa<SymbolRegionValue>(sym);
327}
328
371 markLive(sym);
372 MetadataInUse.erase(sym);
373 return true;
374 }
375 }
376 return false;
377 }
378
379 // Interogate the symbol. It may derive from an input value to
380 // the analyzed function/method.
381 return isa<SymbolRegionValue>(sym);
382}
383
329bool SymbolReaper::isLive(const Stmt* ExprVal) const {
330 return LCtx->getAnalysisContext()->getRelaxedLiveVariables()->
331 isLive(Loc, ExprVal);
384bool SymbolReaper::isLive(const Stmt *ExprVal) const {
385 return LCtx->getAnalysis<RelaxedLiveVariables>()->isLive(Loc, ExprVal);
332}
333
386}
387
334bool SymbolReaper::isLive(const VarRegion *VR) const {
388bool SymbolReaper::isLive(const VarRegion *VR, bool includeStoreBindings) const{
335 const StackFrameContext *VarContext = VR->getStackFrame();
336 const StackFrameContext *CurrentContext = LCtx->getCurrentStackFrame();
337
389 const StackFrameContext *VarContext = VR->getStackFrame();
390 const StackFrameContext *CurrentContext = LCtx->getCurrentStackFrame();
391
338 if (VarContext == CurrentContext)
339 return LCtx->getAnalysisContext()->getRelaxedLiveVariables()->
340 isLive(Loc, VR->getDecl());
392 if (VarContext == CurrentContext) {
393 if (LCtx->getAnalysis<RelaxedLiveVariables>()->isLive(Loc, VR->getDecl()))
394 return true;
341
395
396 if (!includeStoreBindings)
397 return false;
398
399 unsigned &cachedQuery =
400 const_cast<SymbolReaper*>(this)->includedRegionCache[VR];
401
402 if (cachedQuery) {
403 return cachedQuery == 1;
404 }
405
406 // Query the store to see if the region occurs in any live bindings.
407 if (Store store = reapedStore.getStore()) {
408 bool hasRegion =
409 reapedStore.getStoreManager().includedInBindings(store, VR);
410 cachedQuery = hasRegion ? 1 : 2;
411 return hasRegion;
412 }
413
414 return false;
415 }
416
342 return VarContext->isParentOf(CurrentContext);
343}
344
345SymbolVisitor::~SymbolVisitor() {}
417 return VarContext->isParentOf(CurrentContext);
418}
419
420SymbolVisitor::~SymbolVisitor() {}