1 //== AnalysisDeclContext.cpp - Analysis context for Path Sens analysis -*- 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 AnalysisDeclContext, a class that manages the analysis context
11 // data for path sensitive analysis.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "clang/Analysis/AnalysisDeclContext.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/Decl.h"
18 #include "clang/AST/DeclObjC.h"
19 #include "clang/AST/DeclTemplate.h"
20 #include "clang/AST/ParentMap.h"
21 #include "clang/AST/StmtVisitor.h"
22 #include "clang/Analysis/Analyses/CFGReachabilityAnalysis.h"
23 #include "clang/Analysis/Analyses/LiveVariables.h"
24 #include "clang/Analysis/Analyses/PseudoConstantAnalysis.h"
25 #include "clang/Analysis/BodyFarm.h"
26 #include "clang/Analysis/CFG.h"
27 #include "clang/Analysis/CFGStmtMap.h"
28 #include "clang/Analysis/Support/BumpVector.h"
29 #include "llvm/ADT/SmallPtrSet.h"
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/SaveAndRestore.h"
32 #include "llvm/Support/raw_ostream.h"
33 
34 using namespace clang;
35 
36 typedef llvm::DenseMap<const void *, ManagedAnalysis *> ManagedAnalysisMap;
37 
38 AnalysisDeclContext::AnalysisDeclContext(AnalysisDeclContextManager *Mgr,
39                                          const Decl *d,
40                                          const CFG::BuildOptions &buildOptions)
41   : Manager(Mgr),
42     D(d),
43     cfgBuildOptions(buildOptions),
44     forcedBlkExprs(nullptr),
45     builtCFG(false),
46     builtCompleteCFG(false),
47     ReferencedBlockVars(nullptr),
48     ManagedAnalyses(nullptr)
49 {
50   cfgBuildOptions.forcedBlkExprs = &forcedBlkExprs;
51 }
52 
53 AnalysisDeclContext::AnalysisDeclContext(AnalysisDeclContextManager *Mgr,
54                                          const Decl *d)
55 : Manager(Mgr),
56   D(d),
57   forcedBlkExprs(nullptr),
58   builtCFG(false),
59   builtCompleteCFG(false),
60   ReferencedBlockVars(nullptr),
61   ManagedAnalyses(nullptr)
62 {
63   cfgBuildOptions.forcedBlkExprs = &forcedBlkExprs;
64 }
65 
66 AnalysisDeclContextManager::AnalysisDeclContextManager(
67     ASTContext &ASTCtx, bool useUnoptimizedCFG, bool addImplicitDtors,
68     bool addInitializers, bool addTemporaryDtors, bool addLifetime,
69     bool addLoopExit, bool synthesizeBodies, bool addStaticInitBranch,
70     bool addCXXNewAllocator, bool addRichCXXConstructors,
71     CodeInjector *injector)
72     : Injector(injector), FunctionBodyFarm(ASTCtx, injector),
73       SynthesizeBodies(synthesizeBodies) {
74   cfgBuildOptions.PruneTriviallyFalseEdges = !useUnoptimizedCFG;
75   cfgBuildOptions.AddImplicitDtors = addImplicitDtors;
76   cfgBuildOptions.AddInitializers = addInitializers;
77   cfgBuildOptions.AddTemporaryDtors = addTemporaryDtors;
78   cfgBuildOptions.AddLifetime = addLifetime;
79   cfgBuildOptions.AddLoopExit = addLoopExit;
80   cfgBuildOptions.AddStaticInitBranches = addStaticInitBranch;
81   cfgBuildOptions.AddCXXNewAllocator = addCXXNewAllocator;
82   cfgBuildOptions.AddRichCXXConstructors = addRichCXXConstructors;
83 }
84 
85 void AnalysisDeclContextManager::clear() { Contexts.clear(); }
86 
87 Stmt *AnalysisDeclContext::getBody(bool &IsAutosynthesized) const {
88   IsAutosynthesized = false;
89   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
90     Stmt *Body = FD->getBody();
91     if (auto *CoroBody = dyn_cast_or_null<CoroutineBodyStmt>(Body))
92       Body = CoroBody->getBody();
93     if (Manager && Manager->synthesizeBodies()) {
94       Stmt *SynthesizedBody = Manager->getBodyFarm().getBody(FD);
95       if (SynthesizedBody) {
96         Body = SynthesizedBody;
97         IsAutosynthesized = true;
98       }
99     }
100     return Body;
101   }
102   else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
103     Stmt *Body = MD->getBody();
104     if (Manager && Manager->synthesizeBodies()) {
105       Stmt *SynthesizedBody = Manager->getBodyFarm().getBody(MD);
106       if (SynthesizedBody) {
107         Body = SynthesizedBody;
108         IsAutosynthesized = true;
109       }
110     }
111     return Body;
112   } else if (const BlockDecl *BD = dyn_cast<BlockDecl>(D))
113     return BD->getBody();
114   else if (const FunctionTemplateDecl *FunTmpl
115            = dyn_cast_or_null<FunctionTemplateDecl>(D))
116     return FunTmpl->getTemplatedDecl()->getBody();
117 
118   llvm_unreachable("unknown code decl");
119 }
120 
121 Stmt *AnalysisDeclContext::getBody() const {
122   bool Tmp;
123   return getBody(Tmp);
124 }
125 
126 bool AnalysisDeclContext::isBodyAutosynthesized() const {
127   bool Tmp;
128   getBody(Tmp);
129   return Tmp;
130 }
131 
132 bool AnalysisDeclContext::isBodyAutosynthesizedFromModelFile() const {
133   bool Tmp;
134   Stmt *Body = getBody(Tmp);
135   return Tmp && Body->getLocStart().isValid();
136 }
137 
138 /// Returns true if \param VD is an Objective-C implicit 'self' parameter.
139 static bool isSelfDecl(const VarDecl *VD) {
140   return isa<ImplicitParamDecl>(VD) && VD->getName() == "self";
141 }
142 
143 const ImplicitParamDecl *AnalysisDeclContext::getSelfDecl() const {
144   if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D))
145     return MD->getSelfDecl();
146   if (const BlockDecl *BD = dyn_cast<BlockDecl>(D)) {
147     // See if 'self' was captured by the block.
148     for (const auto &I : BD->captures()) {
149       const VarDecl *VD = I.getVariable();
150       if (isSelfDecl(VD))
151         return dyn_cast<ImplicitParamDecl>(VD);
152     }
153   }
154 
155   auto *CXXMethod = dyn_cast<CXXMethodDecl>(D);
156   if (!CXXMethod)
157     return nullptr;
158 
159   const CXXRecordDecl *parent = CXXMethod->getParent();
160   if (!parent->isLambda())
161     return nullptr;
162 
163   for (const LambdaCapture &LC : parent->captures()) {
164     if (!LC.capturesVariable())
165       continue;
166 
167     VarDecl *VD = LC.getCapturedVar();
168     if (isSelfDecl(VD))
169       return dyn_cast<ImplicitParamDecl>(VD);
170   }
171 
172   return nullptr;
173 }
174 
175 void AnalysisDeclContext::registerForcedBlockExpression(const Stmt *stmt) {
176   if (!forcedBlkExprs)
177     forcedBlkExprs = new CFG::BuildOptions::ForcedBlkExprs();
178   // Default construct an entry for 'stmt'.
179   if (const Expr *e = dyn_cast<Expr>(stmt))
180     stmt = e->IgnoreParens();
181   (void) (*forcedBlkExprs)[stmt];
182 }
183 
184 const CFGBlock *
185 AnalysisDeclContext::getBlockForRegisteredExpression(const Stmt *stmt) {
186   assert(forcedBlkExprs);
187   if (const Expr *e = dyn_cast<Expr>(stmt))
188     stmt = e->IgnoreParens();
189   CFG::BuildOptions::ForcedBlkExprs::const_iterator itr =
190     forcedBlkExprs->find(stmt);
191   assert(itr != forcedBlkExprs->end());
192   return itr->second;
193 }
194 
195 /// Add each synthetic statement in the CFG to the parent map, using the
196 /// source statement's parent.
197 static void addParentsForSyntheticStmts(const CFG *TheCFG, ParentMap &PM) {
198   if (!TheCFG)
199     return;
200 
201   for (CFG::synthetic_stmt_iterator I = TheCFG->synthetic_stmt_begin(),
202                                     E = TheCFG->synthetic_stmt_end();
203        I != E; ++I) {
204     PM.setParent(I->first, PM.getParent(I->second));
205   }
206 }
207 
208 CFG *AnalysisDeclContext::getCFG() {
209   if (!cfgBuildOptions.PruneTriviallyFalseEdges)
210     return getUnoptimizedCFG();
211 
212   if (!builtCFG) {
213     cfg = CFG::buildCFG(D, getBody(), &D->getASTContext(), cfgBuildOptions);
214     // Even when the cfg is not successfully built, we don't
215     // want to try building it again.
216     builtCFG = true;
217 
218     if (PM)
219       addParentsForSyntheticStmts(cfg.get(), *PM);
220 
221     // The Observer should only observe one build of the CFG.
222     getCFGBuildOptions().Observer = nullptr;
223   }
224   return cfg.get();
225 }
226 
227 CFG *AnalysisDeclContext::getUnoptimizedCFG() {
228   if (!builtCompleteCFG) {
229     SaveAndRestore<bool> NotPrune(cfgBuildOptions.PruneTriviallyFalseEdges,
230                                   false);
231     completeCFG =
232         CFG::buildCFG(D, getBody(), &D->getASTContext(), cfgBuildOptions);
233     // Even when the cfg is not successfully built, we don't
234     // want to try building it again.
235     builtCompleteCFG = true;
236 
237     if (PM)
238       addParentsForSyntheticStmts(completeCFG.get(), *PM);
239 
240     // The Observer should only observe one build of the CFG.
241     getCFGBuildOptions().Observer = nullptr;
242   }
243   return completeCFG.get();
244 }
245 
246 CFGStmtMap *AnalysisDeclContext::getCFGStmtMap() {
247   if (cfgStmtMap)
248     return cfgStmtMap.get();
249 
250   if (CFG *c = getCFG()) {
251     cfgStmtMap.reset(CFGStmtMap::Build(c, &getParentMap()));
252     return cfgStmtMap.get();
253   }
254 
255   return nullptr;
256 }
257 
258 CFGReverseBlockReachabilityAnalysis *AnalysisDeclContext::getCFGReachablityAnalysis() {
259   if (CFA)
260     return CFA.get();
261 
262   if (CFG *c = getCFG()) {
263     CFA.reset(new CFGReverseBlockReachabilityAnalysis(*c));
264     return CFA.get();
265   }
266 
267   return nullptr;
268 }
269 
270 void AnalysisDeclContext::dumpCFG(bool ShowColors) {
271     getCFG()->dump(getASTContext().getLangOpts(), ShowColors);
272 }
273 
274 ParentMap &AnalysisDeclContext::getParentMap() {
275   if (!PM) {
276     PM.reset(new ParentMap(getBody()));
277     if (const CXXConstructorDecl *C = dyn_cast<CXXConstructorDecl>(getDecl())) {
278       for (const auto *I : C->inits()) {
279         PM->addStmt(I->getInit());
280       }
281     }
282     if (builtCFG)
283       addParentsForSyntheticStmts(getCFG(), *PM);
284     if (builtCompleteCFG)
285       addParentsForSyntheticStmts(getUnoptimizedCFG(), *PM);
286   }
287   return *PM;
288 }
289 
290 PseudoConstantAnalysis *AnalysisDeclContext::getPseudoConstantAnalysis() {
291   if (!PCA)
292     PCA.reset(new PseudoConstantAnalysis(getBody()));
293   return PCA.get();
294 }
295 
296 AnalysisDeclContext *AnalysisDeclContextManager::getContext(const Decl *D) {
297   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
298     // Calling 'hasBody' replaces 'FD' in place with the FunctionDecl
299     // that has the body.
300     FD->hasBody(FD);
301     D = FD;
302   }
303 
304   std::unique_ptr<AnalysisDeclContext> &AC = Contexts[D];
305   if (!AC)
306     AC = llvm::make_unique<AnalysisDeclContext>(this, D, cfgBuildOptions);
307   return AC.get();
308 }
309 
310 BodyFarm &AnalysisDeclContextManager::getBodyFarm() { return FunctionBodyFarm; }
311 
312 const StackFrameContext *
313 AnalysisDeclContext::getStackFrame(LocationContext const *Parent, const Stmt *S,
314                                const CFGBlock *Blk, unsigned Idx) {
315   return getLocationContextManager().getStackFrame(this, Parent, S, Blk, Idx);
316 }
317 
318 const BlockInvocationContext *
319 AnalysisDeclContext::getBlockInvocationContext(const LocationContext *parent,
320                                                const clang::BlockDecl *BD,
321                                                const void *ContextData) {
322   return getLocationContextManager().getBlockInvocationContext(this, parent,
323                                                                BD, ContextData);
324 }
325 
326 bool AnalysisDeclContext::isInStdNamespace(const Decl *D) {
327   const DeclContext *DC = D->getDeclContext()->getEnclosingNamespaceContext();
328   const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(DC);
329   if (!ND)
330     return false;
331 
332   while (const DeclContext *Parent = ND->getParent()) {
333     if (!isa<NamespaceDecl>(Parent))
334       break;
335     ND = cast<NamespaceDecl>(Parent);
336   }
337 
338   return ND->isStdNamespace();
339 }
340 
341 LocationContextManager & AnalysisDeclContext::getLocationContextManager() {
342   assert(Manager &&
343          "Cannot create LocationContexts without an AnalysisDeclContextManager!");
344   return Manager->getLocationContextManager();
345 }
346 
347 //===----------------------------------------------------------------------===//
348 // FoldingSet profiling.
349 //===----------------------------------------------------------------------===//
350 
351 void LocationContext::ProfileCommon(llvm::FoldingSetNodeID &ID,
352                                     ContextKind ck,
353                                     AnalysisDeclContext *ctx,
354                                     const LocationContext *parent,
355                                     const void *data) {
356   ID.AddInteger(ck);
357   ID.AddPointer(ctx);
358   ID.AddPointer(parent);
359   ID.AddPointer(data);
360 }
361 
362 void StackFrameContext::Profile(llvm::FoldingSetNodeID &ID) {
363   Profile(ID, getAnalysisDeclContext(), getParent(), CallSite, Block, Index);
364 }
365 
366 void ScopeContext::Profile(llvm::FoldingSetNodeID &ID) {
367   Profile(ID, getAnalysisDeclContext(), getParent(), Enter);
368 }
369 
370 void BlockInvocationContext::Profile(llvm::FoldingSetNodeID &ID) {
371   Profile(ID, getAnalysisDeclContext(), getParent(), BD, ContextData);
372 }
373 
374 //===----------------------------------------------------------------------===//
375 // LocationContext creation.
376 //===----------------------------------------------------------------------===//
377 
378 template <typename LOC, typename DATA>
379 const LOC*
380 LocationContextManager::getLocationContext(AnalysisDeclContext *ctx,
381                                            const LocationContext *parent,
382                                            const DATA *d) {
383   llvm::FoldingSetNodeID ID;
384   LOC::Profile(ID, ctx, parent, d);
385   void *InsertPos;
386 
387   LOC *L = cast_or_null<LOC>(Contexts.FindNodeOrInsertPos(ID, InsertPos));
388 
389   if (!L) {
390     L = new LOC(ctx, parent, d);
391     Contexts.InsertNode(L, InsertPos);
392   }
393   return L;
394 }
395 
396 const StackFrameContext*
397 LocationContextManager::getStackFrame(AnalysisDeclContext *ctx,
398                                       const LocationContext *parent,
399                                       const Stmt *s,
400                                       const CFGBlock *blk, unsigned idx) {
401   llvm::FoldingSetNodeID ID;
402   StackFrameContext::Profile(ID, ctx, parent, s, blk, idx);
403   void *InsertPos;
404   StackFrameContext *L =
405    cast_or_null<StackFrameContext>(Contexts.FindNodeOrInsertPos(ID, InsertPos));
406   if (!L) {
407     L = new StackFrameContext(ctx, parent, s, blk, idx);
408     Contexts.InsertNode(L, InsertPos);
409   }
410   return L;
411 }
412 
413 const ScopeContext *
414 LocationContextManager::getScope(AnalysisDeclContext *ctx,
415                                  const LocationContext *parent,
416                                  const Stmt *s) {
417   return getLocationContext<ScopeContext, Stmt>(ctx, parent, s);
418 }
419 
420 const BlockInvocationContext *
421 LocationContextManager::getBlockInvocationContext(AnalysisDeclContext *ctx,
422                                                   const LocationContext *parent,
423                                                   const BlockDecl *BD,
424                                                   const void *ContextData) {
425   llvm::FoldingSetNodeID ID;
426   BlockInvocationContext::Profile(ID, ctx, parent, BD, ContextData);
427   void *InsertPos;
428   BlockInvocationContext *L =
429     cast_or_null<BlockInvocationContext>(Contexts.FindNodeOrInsertPos(ID,
430                                                                     InsertPos));
431   if (!L) {
432     L = new BlockInvocationContext(ctx, parent, BD, ContextData);
433     Contexts.InsertNode(L, InsertPos);
434   }
435   return L;
436 }
437 
438 //===----------------------------------------------------------------------===//
439 // LocationContext methods.
440 //===----------------------------------------------------------------------===//
441 
442 const StackFrameContext *LocationContext::getCurrentStackFrame() const {
443   const LocationContext *LC = this;
444   while (LC) {
445     if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC))
446       return SFC;
447     LC = LC->getParent();
448   }
449   return nullptr;
450 }
451 
452 bool LocationContext::inTopFrame() const {
453   return getCurrentStackFrame()->inTopFrame();
454 }
455 
456 bool LocationContext::isParentOf(const LocationContext *LC) const {
457   do {
458     const LocationContext *Parent = LC->getParent();
459     if (Parent == this)
460       return true;
461     else
462       LC = Parent;
463   } while (LC);
464 
465   return false;
466 }
467 
468 static void printLocation(raw_ostream &OS, const SourceManager &SM,
469                           SourceLocation SLoc) {
470   if (SLoc.isFileID() && SM.isInMainFile(SLoc))
471     OS << "line " << SM.getExpansionLineNumber(SLoc);
472   else
473     SLoc.print(OS, SM);
474 }
475 
476 void LocationContext::dumpStack(
477     raw_ostream &OS, StringRef Indent, const char *NL, const char *Sep,
478     std::function<void(const LocationContext *)> printMoreInfoPerContext) const {
479   ASTContext &Ctx = getAnalysisDeclContext()->getASTContext();
480   PrintingPolicy PP(Ctx.getLangOpts());
481   PP.TerseOutput = 1;
482 
483   const SourceManager &SM =
484       getAnalysisDeclContext()->getASTContext().getSourceManager();
485 
486   unsigned Frame = 0;
487   for (const LocationContext *LCtx = this; LCtx; LCtx = LCtx->getParent()) {
488 
489     switch (LCtx->getKind()) {
490     case StackFrame:
491       OS << Indent << '#' << Frame << ' ';
492       ++Frame;
493       if (const NamedDecl *D = dyn_cast<NamedDecl>(LCtx->getDecl()))
494         OS << "Calling " << D->getQualifiedNameAsString();
495       else
496         OS << "Calling anonymous code";
497       if (const Stmt *S = cast<StackFrameContext>(LCtx)->getCallSite()) {
498         OS << " at ";
499         printLocation(OS, SM, S->getLocStart());
500       }
501       break;
502     case Scope:
503       OS << "Entering scope";
504       break;
505     case Block:
506       OS << "Invoking block";
507       if (const Decl *D = cast<BlockInvocationContext>(LCtx)->getDecl()) {
508         OS << " defined at ";
509         printLocation(OS, SM, D->getLocStart());
510       }
511       break;
512     }
513     OS << NL;
514 
515     printMoreInfoPerContext(LCtx);
516   }
517 }
518 
519 LLVM_DUMP_METHOD void LocationContext::dumpStack() const {
520   dumpStack(llvm::errs());
521 }
522 
523 //===----------------------------------------------------------------------===//
524 // Lazily generated map to query the external variables referenced by a Block.
525 //===----------------------------------------------------------------------===//
526 
527 namespace {
528 class FindBlockDeclRefExprsVals : public StmtVisitor<FindBlockDeclRefExprsVals>{
529   BumpVector<const VarDecl*> &BEVals;
530   BumpVectorContext &BC;
531   llvm::SmallPtrSet<const VarDecl*, 4> Visited;
532   llvm::SmallPtrSet<const DeclContext*, 4> IgnoredContexts;
533 public:
534   FindBlockDeclRefExprsVals(BumpVector<const VarDecl*> &bevals,
535                             BumpVectorContext &bc)
536   : BEVals(bevals), BC(bc) {}
537 
538   void VisitStmt(Stmt *S) {
539     for (Stmt *Child : S->children())
540       if (Child)
541         Visit(Child);
542   }
543 
544   void VisitDeclRefExpr(DeclRefExpr *DR) {
545     // Non-local variables are also directly modified.
546     if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl())) {
547       if (!VD->hasLocalStorage()) {
548         if (Visited.insert(VD).second)
549           BEVals.push_back(VD, BC);
550       }
551     }
552   }
553 
554   void VisitBlockExpr(BlockExpr *BR) {
555     // Blocks containing blocks can transitively capture more variables.
556     IgnoredContexts.insert(BR->getBlockDecl());
557     Visit(BR->getBlockDecl()->getBody());
558   }
559 
560   void VisitPseudoObjectExpr(PseudoObjectExpr *PE) {
561     for (PseudoObjectExpr::semantics_iterator it = PE->semantics_begin(),
562          et = PE->semantics_end(); it != et; ++it) {
563       Expr *Semantic = *it;
564       if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(Semantic))
565         Semantic = OVE->getSourceExpr();
566       Visit(Semantic);
567     }
568   }
569 };
570 } // end anonymous namespace
571 
572 typedef BumpVector<const VarDecl*> DeclVec;
573 
574 static DeclVec* LazyInitializeReferencedDecls(const BlockDecl *BD,
575                                               void *&Vec,
576                                               llvm::BumpPtrAllocator &A) {
577   if (Vec)
578     return (DeclVec*) Vec;
579 
580   BumpVectorContext BC(A);
581   DeclVec *BV = (DeclVec*) A.Allocate<DeclVec>();
582   new (BV) DeclVec(BC, 10);
583 
584   // Go through the capture list.
585   for (const auto &CI : BD->captures()) {
586     BV->push_back(CI.getVariable(), BC);
587   }
588 
589   // Find the referenced global/static variables.
590   FindBlockDeclRefExprsVals F(*BV, BC);
591   F.Visit(BD->getBody());
592 
593   Vec = BV;
594   return BV;
595 }
596 
597 llvm::iterator_range<AnalysisDeclContext::referenced_decls_iterator>
598 AnalysisDeclContext::getReferencedBlockVars(const BlockDecl *BD) {
599   if (!ReferencedBlockVars)
600     ReferencedBlockVars = new llvm::DenseMap<const BlockDecl*,void*>();
601 
602   const DeclVec *V =
603       LazyInitializeReferencedDecls(BD, (*ReferencedBlockVars)[BD], A);
604   return llvm::make_range(V->begin(), V->end());
605 }
606 
607 ManagedAnalysis *&AnalysisDeclContext::getAnalysisImpl(const void *tag) {
608   if (!ManagedAnalyses)
609     ManagedAnalyses = new ManagedAnalysisMap();
610   ManagedAnalysisMap *M = (ManagedAnalysisMap*) ManagedAnalyses;
611   return (*M)[tag];
612 }
613 
614 //===----------------------------------------------------------------------===//
615 // Cleanup.
616 //===----------------------------------------------------------------------===//
617 
618 ManagedAnalysis::~ManagedAnalysis() {}
619 
620 AnalysisDeclContext::~AnalysisDeclContext() {
621   delete forcedBlkExprs;
622   delete ReferencedBlockVars;
623   // Release the managed analyses.
624   if (ManagedAnalyses) {
625     ManagedAnalysisMap *M = (ManagedAnalysisMap*) ManagedAnalyses;
626     llvm::DeleteContainerSeconds(*M);
627     delete M;
628   }
629 }
630 
631 LocationContext::~LocationContext() {}
632 
633 LocationContextManager::~LocationContextManager() {
634   clear();
635 }
636 
637 void LocationContextManager::clear() {
638   for (llvm::FoldingSet<LocationContext>::iterator I = Contexts.begin(),
639        E = Contexts.end(); I != E; ) {
640     LocationContext *LC = &*I;
641     ++I;
642     delete LC;
643   }
644 
645   Contexts.clear();
646 }
647 
648