1 //===--- AnalysisConsumer.cpp - ASTConsumer for running Analyses ----------===//
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 // "Meta" ASTConsumer for running different source analyses.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #define DEBUG_TYPE "AnalysisConsumer"
15 
16 #include "AnalysisConsumer.h"
17 #include "clang/AST/ASTConsumer.h"
18 #include "clang/AST/Decl.h"
19 #include "clang/AST/DeclCXX.h"
20 #include "clang/AST/DeclObjC.h"
21 #include "clang/AST/ParentMap.h"
22 #include "clang/AST/RecursiveASTVisitor.h"
23 #include "clang/Analysis/Analyses/LiveVariables.h"
24 #include "clang/Analysis/CFG.h"
25 #include "clang/Analysis/CallGraph.h"
26 #include "clang/Basic/FileManager.h"
27 #include "clang/Basic/SourceManager.h"
28 #include "clang/Lex/Preprocessor.h"
29 #include "clang/StaticAnalyzer/Checkers/LocalCheckers.h"
30 #include "clang/StaticAnalyzer/Core/AnalyzerOptions.h"
31 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
32 #include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
33 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
34 #include "clang/StaticAnalyzer/Core/PathDiagnosticConsumers.h"
35 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
36 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
37 #include "clang/StaticAnalyzer/Frontend/CheckerRegistration.h"
38 #include "llvm/ADT/DepthFirstIterator.h"
39 #include "llvm/ADT/OwningPtr.h"
40 #include "llvm/ADT/SmallPtrSet.h"
41 #include "llvm/ADT/Statistic.h"
42 #include "llvm/Support/Path.h"
43 #include "llvm/Support/Program.h"
44 #include "llvm/Support/Timer.h"
45 #include "llvm/Support/raw_ostream.h"
46 #include <queue>
47 
48 using namespace clang;
49 using namespace ento;
50 using llvm::SmallPtrSet;
51 
52 static ExplodedNode::Auditor* CreateUbiViz();
53 
54 STATISTIC(NumFunctionTopLevel, "The # of functions at top level.");
55 STATISTIC(NumFunctionsAnalyzed, "The # of functions analysed (as top level).");
56 STATISTIC(NumBlocksInAnalyzedFunctions,
57                      "The # of basic blocks in the analyzed functions.");
58 STATISTIC(PercentReachableBlocks, "The % of reachable basic blocks.");
59 STATISTIC(MaxCFGSize, "The maximum number of basic blocks in a function.");
60 
61 //===----------------------------------------------------------------------===//
62 // Special PathDiagnosticConsumers.
63 //===----------------------------------------------------------------------===//
64 
65 static void createPlistHTMLDiagnosticConsumer(PathDiagnosticConsumers &C,
66                                               const std::string &prefix,
67                                               const Preprocessor &PP) {
68   createHTMLDiagnosticConsumer(C, llvm::sys::path::parent_path(prefix), PP);
69   createPlistDiagnosticConsumer(C, prefix, PP);
70 }
71 
72 namespace {
73 class ClangDiagPathDiagConsumer : public PathDiagnosticConsumer {
74   DiagnosticsEngine &Diag;
75 public:
76   ClangDiagPathDiagConsumer(DiagnosticsEngine &Diag) : Diag(Diag) {}
77   virtual ~ClangDiagPathDiagConsumer() {}
78   virtual StringRef getName() const { return "ClangDiags"; }
79   virtual PathGenerationScheme getGenerationScheme() const { return None; }
80 
81   void FlushDiagnosticsImpl(std::vector<const PathDiagnostic *> &Diags,
82                             FilesMade *filesMade) {
83     for (std::vector<const PathDiagnostic*>::iterator I = Diags.begin(),
84          E = Diags.end(); I != E; ++I) {
85       const PathDiagnostic *PD = *I;
86       StringRef desc = PD->getShortDescription();
87       SmallString<512> TmpStr;
88       llvm::raw_svector_ostream Out(TmpStr);
89       for (StringRef::iterator I=desc.begin(), E=desc.end(); I!=E; ++I) {
90         if (*I == '%')
91           Out << "%%";
92         else
93           Out << *I;
94       }
95       Out.flush();
96       unsigned ErrorDiag = Diag.getCustomDiagID(DiagnosticsEngine::Warning,
97                                                 TmpStr);
98       SourceLocation L = PD->getLocation().asLocation();
99       DiagnosticBuilder diagBuilder = Diag.Report(L, ErrorDiag);
100 
101       // Get the ranges from the last point in the path.
102       ArrayRef<SourceRange> Ranges = PD->path.back()->getRanges();
103 
104       for (ArrayRef<SourceRange>::iterator I = Ranges.begin(),
105                                            E = Ranges.end(); I != E; ++I) {
106         diagBuilder << *I;
107       }
108     }
109   }
110 };
111 } // end anonymous namespace
112 
113 //===----------------------------------------------------------------------===//
114 // AnalysisConsumer declaration.
115 //===----------------------------------------------------------------------===//
116 
117 namespace {
118 
119 class AnalysisConsumer : public ASTConsumer,
120                          public RecursiveASTVisitor<AnalysisConsumer> {
121   enum {
122     AM_None = 0,
123     AM_Syntax = 0x1,
124     AM_Path = 0x2
125   };
126   typedef unsigned AnalysisMode;
127 
128   /// Mode of the analyzes while recursively visiting Decls.
129   AnalysisMode RecVisitorMode;
130   /// Bug Reporter to use while recursively visiting Decls.
131   BugReporter *RecVisitorBR;
132 
133 public:
134   ASTContext *Ctx;
135   const Preprocessor &PP;
136   const std::string OutDir;
137   AnalyzerOptionsRef Opts;
138   ArrayRef<std::string> Plugins;
139 
140   /// \brief Stores the declarations from the local translation unit.
141   /// Note, we pre-compute the local declarations at parse time as an
142   /// optimization to make sure we do not deserialize everything from disk.
143   /// The local declaration to all declarations ratio might be very small when
144   /// working with a PCH file.
145   SetOfDecls LocalTUDecls;
146 
147   // Set of PathDiagnosticConsumers.  Owned by AnalysisManager.
148   PathDiagnosticConsumers PathConsumers;
149 
150   StoreManagerCreator CreateStoreMgr;
151   ConstraintManagerCreator CreateConstraintMgr;
152 
153   OwningPtr<CheckerManager> checkerMgr;
154   OwningPtr<AnalysisManager> Mgr;
155 
156   /// Time the analyzes time of each translation unit.
157   static llvm::Timer* TUTotalTimer;
158 
159   /// The information about analyzed functions shared throughout the
160   /// translation unit.
161   FunctionSummariesTy FunctionSummaries;
162 
163   AnalysisConsumer(const Preprocessor& pp,
164                    const std::string& outdir,
165                    AnalyzerOptionsRef opts,
166                    ArrayRef<std::string> plugins)
167     : RecVisitorMode(0), RecVisitorBR(0),
168       Ctx(0), PP(pp), OutDir(outdir), Opts(opts), Plugins(plugins) {
169     DigestAnalyzerOptions();
170     if (Opts->PrintStats) {
171       llvm::EnableStatistics();
172       TUTotalTimer = new llvm::Timer("Analyzer Total Time");
173     }
174   }
175 
176   ~AnalysisConsumer() {
177     if (Opts->PrintStats)
178       delete TUTotalTimer;
179   }
180 
181   void DigestAnalyzerOptions() {
182     // Create the PathDiagnosticConsumer.
183     PathConsumers.push_back(new ClangDiagPathDiagConsumer(PP.getDiagnostics()));
184 
185     if (!OutDir.empty()) {
186       switch (Opts->AnalysisDiagOpt) {
187       default:
188 #define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATEFN, AUTOCREATE) \
189         case PD_##NAME: CREATEFN(PathConsumers, OutDir, PP); break;
190 #include "clang/StaticAnalyzer/Core/Analyses.def"
191       }
192     } else if (Opts->AnalysisDiagOpt == PD_TEXT) {
193       // Create the text client even without a specified output file since
194       // it just uses diagnostic notes.
195       createTextPathDiagnosticConsumer(PathConsumers, "", PP);
196     }
197 
198     // Create the analyzer component creators.
199     switch (Opts->AnalysisStoreOpt) {
200     default:
201       llvm_unreachable("Unknown store manager.");
202 #define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATEFN)           \
203       case NAME##Model: CreateStoreMgr = CREATEFN; break;
204 #include "clang/StaticAnalyzer/Core/Analyses.def"
205     }
206 
207     switch (Opts->AnalysisConstraintsOpt) {
208     default:
209       llvm_unreachable("Unknown store manager.");
210 #define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATEFN)     \
211       case NAME##Model: CreateConstraintMgr = CREATEFN; break;
212 #include "clang/StaticAnalyzer/Core/Analyses.def"
213     }
214   }
215 
216   void DisplayFunction(const Decl *D, AnalysisMode Mode) {
217     if (!Opts->AnalyzerDisplayProgress)
218       return;
219 
220     SourceManager &SM = Mgr->getASTContext().getSourceManager();
221     PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
222     if (Loc.isValid()) {
223       llvm::errs() << "ANALYZE";
224 
225       if (Mode == AM_Syntax)
226         llvm::errs() << " (Syntax)";
227       else if (Mode == AM_Path)
228         llvm::errs() << " (Path)";
229       else
230         assert(Mode == (AM_Syntax | AM_Path) && "Unexpected mode!");
231 
232       llvm::errs() << ": " << Loc.getFilename();
233       if (isa<FunctionDecl>(D) || isa<ObjCMethodDecl>(D)) {
234         const NamedDecl *ND = cast<NamedDecl>(D);
235         llvm::errs() << ' ' << *ND << '\n';
236       }
237       else if (isa<BlockDecl>(D)) {
238         llvm::errs() << ' ' << "block(line:" << Loc.getLine() << ",col:"
239                      << Loc.getColumn() << '\n';
240       }
241       else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
242         Selector S = MD->getSelector();
243         llvm::errs() << ' ' << S.getAsString();
244       }
245     }
246   }
247 
248   virtual void Initialize(ASTContext &Context) {
249     Ctx = &Context;
250     checkerMgr.reset(createCheckerManager(*Opts, PP.getLangOpts(), Plugins,
251                                           PP.getDiagnostics()));
252     Mgr.reset(new AnalysisManager(*Ctx,
253                                   PP.getDiagnostics(),
254                                   PP.getLangOpts(),
255                                   PathConsumers,
256                                   CreateStoreMgr,
257                                   CreateConstraintMgr,
258                                   checkerMgr.get(),
259                                   *Opts));
260   }
261 
262   /// \brief Store the top level decls in the set to be processed later on.
263   /// (Doing this pre-processing avoids deserialization of data from PCH.)
264   virtual bool HandleTopLevelDecl(DeclGroupRef D);
265   virtual void HandleTopLevelDeclInObjCContainer(DeclGroupRef D);
266 
267   virtual void HandleTranslationUnit(ASTContext &C);
268 
269   /// \brief Build the call graph for all the top level decls of this TU and
270   /// use it to define the order in which the functions should be visited.
271   void HandleDeclsCallGraph(const unsigned LocalTUDeclsSize);
272 
273   /// \brief Run analyzes(syntax or path sensitive) on the given function.
274   /// \param Mode - determines if we are requesting syntax only or path
275   /// sensitive only analysis.
276   /// \param VisitedCallees - The output parameter, which is populated with the
277   /// set of functions which should be considered analyzed after analyzing the
278   /// given root function.
279   void HandleCode(Decl *D, AnalysisMode Mode,
280                   SetOfConstDecls *VisitedCallees = 0);
281 
282   void RunPathSensitiveChecks(Decl *D, SetOfConstDecls *VisitedCallees);
283   void ActionExprEngine(Decl *D, bool ObjCGCEnabled,
284                         SetOfConstDecls *VisitedCallees);
285 
286   /// Visitors for the RecursiveASTVisitor.
287   bool shouldWalkTypesOfTypeLocs() const { return false; }
288 
289   /// Handle callbacks for arbitrary Decls.
290   bool VisitDecl(Decl *D) {
291     AnalysisMode Mode = getModeForDecl(D, RecVisitorMode);
292     if (Mode & AM_Syntax)
293       checkerMgr->runCheckersOnASTDecl(D, *Mgr, *RecVisitorBR);
294     return true;
295   }
296 
297   bool VisitFunctionDecl(FunctionDecl *FD) {
298     IdentifierInfo *II = FD->getIdentifier();
299     if (II && II->getName().startswith("__inline"))
300       return true;
301 
302     // We skip function template definitions, as their semantics is
303     // only determined when they are instantiated.
304     if (FD->isThisDeclarationADefinition() &&
305         !FD->isDependentContext()) {
306       HandleCode(FD, RecVisitorMode);
307     }
308     return true;
309   }
310 
311   bool VisitObjCMethodDecl(ObjCMethodDecl *MD) {
312     if (MD->isThisDeclarationADefinition())
313       HandleCode(MD, RecVisitorMode);
314     return true;
315   }
316 
317 private:
318   void storeTopLevelDecls(DeclGroupRef DG);
319 
320   /// \brief Check if we should skip (not analyze) the given function.
321   AnalysisMode getModeForDecl(Decl *D, AnalysisMode Mode);
322 
323 };
324 } // end anonymous namespace
325 
326 
327 //===----------------------------------------------------------------------===//
328 // AnalysisConsumer implementation.
329 //===----------------------------------------------------------------------===//
330 llvm::Timer* AnalysisConsumer::TUTotalTimer = 0;
331 
332 bool AnalysisConsumer::HandleTopLevelDecl(DeclGroupRef DG) {
333   storeTopLevelDecls(DG);
334   return true;
335 }
336 
337 void AnalysisConsumer::HandleTopLevelDeclInObjCContainer(DeclGroupRef DG) {
338   storeTopLevelDecls(DG);
339 }
340 
341 void AnalysisConsumer::storeTopLevelDecls(DeclGroupRef DG) {
342   for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I) {
343 
344     // Skip ObjCMethodDecl, wait for the objc container to avoid
345     // analyzing twice.
346     if (isa<ObjCMethodDecl>(*I))
347       continue;
348 
349     LocalTUDecls.push_back(*I);
350   }
351 }
352 
353 static bool shouldSkipFunction(CallGraphNode *N,
354                                SmallPtrSet<CallGraphNode*,24> Visited) {
355   // We want to re-analyse the functions as top level in several cases:
356   // - The 'init' methods should be reanalyzed because
357   //   ObjCNonNilReturnValueChecker assumes that '[super init]' never returns
358   //   'nil' and unless we analyze the 'init' functions as top level, we will not
359   //   catch errors within defensive code.
360   // - We want to reanalyze all ObjC methods as top level to report Retain
361   //   Count naming convention errors more aggressively.
362   if (isa<ObjCMethodDecl>(N->getDecl()))
363     return false;
364 
365   // Otherwise, if we visited the function before, do not reanalyze it.
366   return Visited.count(N);
367 }
368 
369 void AnalysisConsumer::HandleDeclsCallGraph(const unsigned LocalTUDeclsSize) {
370   // Otherwise, use the Callgraph to derive the order.
371   // Build the Call Graph.
372   CallGraph CG;
373 
374   // Add all the top level declarations to the graph.
375   // Note: CallGraph can trigger deserialization of more items from a pch
376   // (though HandleInterestingDecl); triggering additions to LocalTUDecls.
377   // We rely on random access to add the initially processed Decls to CG.
378   for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) {
379     CG.addToCallGraph(LocalTUDecls[i]);
380   }
381 
382   // Find the top level nodes - children of root + the unreachable (parentless)
383   // nodes.
384   llvm::SmallVector<CallGraphNode*, 24> TopLevelFunctions;
385   for (CallGraph::nodes_iterator TI = CG.parentless_begin(),
386                                  TE = CG.parentless_end(); TI != TE; ++TI) {
387     TopLevelFunctions.push_back(*TI);
388     NumFunctionTopLevel++;
389   }
390   CallGraphNode *Entry = CG.getRoot();
391   for (CallGraphNode::iterator I = Entry->begin(),
392                                E = Entry->end(); I != E; ++I) {
393     TopLevelFunctions.push_back(*I);
394     NumFunctionTopLevel++;
395   }
396 
397   // Make sure the nodes are sorted in order reverse of their definition in the
398   // translation unit. This step is very important for performance. It ensures
399   // that we analyze the root functions before the externally available
400   // subroutines.
401   std::deque<CallGraphNode*> BFSQueue;
402   for (llvm::SmallVector<CallGraphNode*, 24>::reverse_iterator
403          TI = TopLevelFunctions.rbegin(), TE = TopLevelFunctions.rend();
404          TI != TE; ++TI)
405     BFSQueue.push_back(*TI);
406 
407   // BFS over all of the functions, while skipping the ones inlined into
408   // the previously processed functions. Use external Visited set, which is
409   // also modified when we inline a function.
410   SmallPtrSet<CallGraphNode*,24> Visited;
411   while(!BFSQueue.empty()) {
412     CallGraphNode *N = BFSQueue.front();
413     BFSQueue.pop_front();
414 
415     // Push the children into the queue.
416     for (CallGraphNode::const_iterator CI = N->begin(),
417          CE = N->end(); CI != CE; ++CI) {
418       if (!shouldSkipFunction(*CI, Visited))
419         BFSQueue.push_back(*CI);
420     }
421 
422     // Skip the functions which have been processed already or previously
423     // inlined.
424     if (shouldSkipFunction(N, Visited))
425       continue;
426 
427     // Analyze the function.
428     SetOfConstDecls VisitedCallees;
429     Decl *D = N->getDecl();
430     assert(D);
431     HandleCode(D, AM_Path,
432                (Mgr->options.InliningMode == All ? 0 : &VisitedCallees));
433 
434     // Add the visited callees to the global visited set.
435     for (SetOfConstDecls::iterator I = VisitedCallees.begin(),
436                                    E = VisitedCallees.end(); I != E; ++I) {
437       CallGraphNode *VN = CG.getNode(*I);
438       if (VN)
439         Visited.insert(VN);
440     }
441     Visited.insert(N);
442   }
443 }
444 
445 void AnalysisConsumer::HandleTranslationUnit(ASTContext &C) {
446   // Don't run the actions if an error has occurred with parsing the file.
447   DiagnosticsEngine &Diags = PP.getDiagnostics();
448   if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred())
449     return;
450 
451   {
452     if (TUTotalTimer) TUTotalTimer->startTimer();
453 
454     // Introduce a scope to destroy BR before Mgr.
455     BugReporter BR(*Mgr);
456     TranslationUnitDecl *TU = C.getTranslationUnitDecl();
457     checkerMgr->runCheckersOnASTDecl(TU, *Mgr, BR);
458 
459     // Run the AST-only checks using the order in which functions are defined.
460     // If inlining is not turned on, use the simplest function order for path
461     // sensitive analyzes as well.
462     RecVisitorMode = AM_Syntax;
463     if (!Mgr->shouldInlineCall())
464       RecVisitorMode |= AM_Path;
465     RecVisitorBR = &BR;
466 
467     // Process all the top level declarations.
468     //
469     // Note: TraverseDecl may modify LocalTUDecls, but only by appending more
470     // entries.  Thus we don't use an iterator, but rely on LocalTUDecls
471     // random access.  By doing so, we automatically compensate for iterators
472     // possibly being invalidated, although this is a bit slower.
473     const unsigned LocalTUDeclsSize = LocalTUDecls.size();
474     for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) {
475       TraverseDecl(LocalTUDecls[i]);
476     }
477 
478     if (Mgr->shouldInlineCall())
479       HandleDeclsCallGraph(LocalTUDeclsSize);
480 
481     // After all decls handled, run checkers on the entire TranslationUnit.
482     checkerMgr->runCheckersOnEndOfTranslationUnit(TU, *Mgr, BR);
483 
484     RecVisitorBR = 0;
485   }
486 
487   // Explicitly destroy the PathDiagnosticConsumer.  This will flush its output.
488   // FIXME: This should be replaced with something that doesn't rely on
489   // side-effects in PathDiagnosticConsumer's destructor. This is required when
490   // used with option -disable-free.
491   Mgr.reset(NULL);
492 
493   if (TUTotalTimer) TUTotalTimer->stopTimer();
494 
495   // Count how many basic blocks we have not covered.
496   NumBlocksInAnalyzedFunctions = FunctionSummaries.getTotalNumBasicBlocks();
497   if (NumBlocksInAnalyzedFunctions > 0)
498     PercentReachableBlocks =
499       (FunctionSummaries.getTotalNumVisitedBasicBlocks() * 100) /
500         NumBlocksInAnalyzedFunctions;
501 
502 }
503 
504 static void FindBlocks(DeclContext *D, SmallVectorImpl<Decl*> &WL) {
505   if (BlockDecl *BD = dyn_cast<BlockDecl>(D))
506     WL.push_back(BD);
507 
508   for (DeclContext::decl_iterator I = D->decls_begin(), E = D->decls_end();
509        I!=E; ++I)
510     if (DeclContext *DC = dyn_cast<DeclContext>(*I))
511       FindBlocks(DC, WL);
512 }
513 
514 static std::string getFunctionName(const Decl *D) {
515   if (const ObjCMethodDecl *ID = dyn_cast<ObjCMethodDecl>(D)) {
516     return ID->getSelector().getAsString();
517   }
518   if (const FunctionDecl *ND = dyn_cast<FunctionDecl>(D)) {
519     IdentifierInfo *II = ND->getIdentifier();
520     if (II)
521       return II->getName();
522   }
523   return "";
524 }
525 
526 AnalysisConsumer::AnalysisMode
527 AnalysisConsumer::getModeForDecl(Decl *D, AnalysisMode Mode) {
528   if (!Opts->AnalyzeSpecificFunction.empty() &&
529       getFunctionName(D) != Opts->AnalyzeSpecificFunction)
530     return AM_None;
531 
532   // Unless -analyze-all is specified, treat decls differently depending on
533   // where they came from:
534   // - Main source file: run both path-sensitive and non-path-sensitive checks.
535   // - Header files: run non-path-sensitive checks only.
536   // - System headers: don't run any checks.
537   SourceManager &SM = Ctx->getSourceManager();
538   SourceLocation SL = SM.getExpansionLoc(D->getLocation());
539   if (!Opts->AnalyzeAll && !SM.isFromMainFile(SL)) {
540     if (SL.isInvalid() || SM.isInSystemHeader(SL))
541       return AM_None;
542     return Mode & ~AM_Path;
543   }
544 
545   return Mode;
546 }
547 
548 void AnalysisConsumer::HandleCode(Decl *D, AnalysisMode Mode,
549                                   SetOfConstDecls *VisitedCallees) {
550   Mode = getModeForDecl(D, Mode);
551   if (Mode == AM_None)
552     return;
553 
554   DisplayFunction(D, Mode);
555   CFG *DeclCFG = Mgr->getCFG(D);
556   if (DeclCFG) {
557     unsigned CFGSize = DeclCFG->size();
558     MaxCFGSize = MaxCFGSize < CFGSize ? CFGSize : MaxCFGSize;
559   }
560 
561 
562   // Clear the AnalysisManager of old AnalysisDeclContexts.
563   Mgr->ClearContexts();
564 
565   // Dispatch on the actions.
566   SmallVector<Decl*, 10> WL;
567   WL.push_back(D);
568 
569   if (D->hasBody() && Opts->AnalyzeNestedBlocks)
570     FindBlocks(cast<DeclContext>(D), WL);
571 
572   BugReporter BR(*Mgr);
573   for (SmallVectorImpl<Decl*>::iterator WI=WL.begin(), WE=WL.end();
574        WI != WE; ++WI)
575     if ((*WI)->hasBody()) {
576       if (Mode & AM_Syntax)
577         checkerMgr->runCheckersOnASTBody(*WI, *Mgr, BR);
578       if ((Mode & AM_Path) && checkerMgr->hasPathSensitiveCheckers()) {
579         RunPathSensitiveChecks(*WI, VisitedCallees);
580         NumFunctionsAnalyzed++;
581       }
582     }
583 }
584 
585 //===----------------------------------------------------------------------===//
586 // Path-sensitive checking.
587 //===----------------------------------------------------------------------===//
588 
589 void AnalysisConsumer::ActionExprEngine(Decl *D, bool ObjCGCEnabled,
590                                         SetOfConstDecls *VisitedCallees) {
591   // Construct the analysis engine.  First check if the CFG is valid.
592   // FIXME: Inter-procedural analysis will need to handle invalid CFGs.
593   if (!Mgr->getCFG(D))
594     return;
595 
596   // See if the LiveVariables analysis scales.
597   if (!Mgr->getAnalysisDeclContext(D)->getAnalysis<RelaxedLiveVariables>())
598     return;
599 
600   ExprEngine Eng(*Mgr, ObjCGCEnabled, VisitedCallees, &FunctionSummaries);
601 
602   // Set the graph auditor.
603   OwningPtr<ExplodedNode::Auditor> Auditor;
604   if (Mgr->options.visualizeExplodedGraphWithUbiGraph) {
605     Auditor.reset(CreateUbiViz());
606     ExplodedNode::SetAuditor(Auditor.get());
607   }
608 
609   // Execute the worklist algorithm.
610   Eng.ExecuteWorkList(Mgr->getAnalysisDeclContextManager().getStackFrame(D),
611                       Mgr->options.MaxNodes);
612 
613   // Release the auditor (if any) so that it doesn't monitor the graph
614   // created BugReporter.
615   ExplodedNode::SetAuditor(0);
616 
617   // Visualize the exploded graph.
618   if (Mgr->options.visualizeExplodedGraphWithGraphViz)
619     Eng.ViewGraph(Mgr->options.TrimGraph);
620 
621   // Display warnings.
622   Eng.getBugReporter().FlushReports();
623 }
624 
625 void AnalysisConsumer::RunPathSensitiveChecks(Decl *D,
626                                               SetOfConstDecls *Visited) {
627 
628   switch (Mgr->getLangOpts().getGC()) {
629   case LangOptions::NonGC:
630     ActionExprEngine(D, false, Visited);
631     break;
632 
633   case LangOptions::GCOnly:
634     ActionExprEngine(D, true, Visited);
635     break;
636 
637   case LangOptions::HybridGC:
638     ActionExprEngine(D, false, Visited);
639     ActionExprEngine(D, true, Visited);
640     break;
641   }
642 }
643 
644 //===----------------------------------------------------------------------===//
645 // AnalysisConsumer creation.
646 //===----------------------------------------------------------------------===//
647 
648 ASTConsumer* ento::CreateAnalysisConsumer(const Preprocessor& pp,
649                                           const std::string& outDir,
650                                           AnalyzerOptionsRef opts,
651                                           ArrayRef<std::string> plugins) {
652   // Disable the effects of '-Werror' when using the AnalysisConsumer.
653   pp.getDiagnostics().setWarningsAsErrors(false);
654 
655   return new AnalysisConsumer(pp, outDir, opts, plugins);
656 }
657 
658 //===----------------------------------------------------------------------===//
659 // Ubigraph Visualization.  FIXME: Move to separate file.
660 //===----------------------------------------------------------------------===//
661 
662 namespace {
663 
664 class UbigraphViz : public ExplodedNode::Auditor {
665   OwningPtr<raw_ostream> Out;
666   llvm::sys::Path Dir, Filename;
667   unsigned Cntr;
668 
669   typedef llvm::DenseMap<void*,unsigned> VMap;
670   VMap M;
671 
672 public:
673   UbigraphViz(raw_ostream *out, llvm::sys::Path& dir,
674               llvm::sys::Path& filename);
675 
676   ~UbigraphViz();
677 
678   virtual void AddEdge(ExplodedNode *Src, ExplodedNode *Dst);
679 };
680 
681 } // end anonymous namespace
682 
683 static ExplodedNode::Auditor* CreateUbiViz() {
684   std::string ErrMsg;
685 
686   llvm::sys::Path Dir = llvm::sys::Path::GetTemporaryDirectory(&ErrMsg);
687   if (!ErrMsg.empty())
688     return 0;
689 
690   llvm::sys::Path Filename = Dir;
691   Filename.appendComponent("llvm_ubi");
692   Filename.makeUnique(true,&ErrMsg);
693 
694   if (!ErrMsg.empty())
695     return 0;
696 
697   llvm::errs() << "Writing '" << Filename.str() << "'.\n";
698 
699   OwningPtr<llvm::raw_fd_ostream> Stream;
700   Stream.reset(new llvm::raw_fd_ostream(Filename.c_str(), ErrMsg));
701 
702   if (!ErrMsg.empty())
703     return 0;
704 
705   return new UbigraphViz(Stream.take(), Dir, Filename);
706 }
707 
708 void UbigraphViz::AddEdge(ExplodedNode *Src, ExplodedNode *Dst) {
709 
710   assert (Src != Dst && "Self-edges are not allowed.");
711 
712   // Lookup the Src.  If it is a new node, it's a root.
713   VMap::iterator SrcI= M.find(Src);
714   unsigned SrcID;
715 
716   if (SrcI == M.end()) {
717     M[Src] = SrcID = Cntr++;
718     *Out << "('vertex', " << SrcID << ", ('color','#00ff00'))\n";
719   }
720   else
721     SrcID = SrcI->second;
722 
723   // Lookup the Dst.
724   VMap::iterator DstI= M.find(Dst);
725   unsigned DstID;
726 
727   if (DstI == M.end()) {
728     M[Dst] = DstID = Cntr++;
729     *Out << "('vertex', " << DstID << ")\n";
730   }
731   else {
732     // We have hit DstID before.  Change its style to reflect a cache hit.
733     DstID = DstI->second;
734     *Out << "('change_vertex_style', " << DstID << ", 1)\n";
735   }
736 
737   // Add the edge.
738   *Out << "('edge', " << SrcID << ", " << DstID
739        << ", ('arrow','true'), ('oriented', 'true'))\n";
740 }
741 
742 UbigraphViz::UbigraphViz(raw_ostream *out, llvm::sys::Path& dir,
743                          llvm::sys::Path& filename)
744   : Out(out), Dir(dir), Filename(filename), Cntr(0) {
745 
746   *Out << "('vertex_style_attribute', 0, ('shape', 'icosahedron'))\n";
747   *Out << "('vertex_style', 1, 0, ('shape', 'sphere'), ('color', '#ffcc66'),"
748           " ('size', '1.5'))\n";
749 }
750 
751 UbigraphViz::~UbigraphViz() {
752   Out.reset(0);
753   llvm::errs() << "Running 'ubiviz' program... ";
754   std::string ErrMsg;
755   llvm::sys::Path Ubiviz = llvm::sys::Program::FindProgramByName("ubiviz");
756   std::vector<const char*> args;
757   args.push_back(Ubiviz.c_str());
758   args.push_back(Filename.c_str());
759   args.push_back(0);
760 
761   if (llvm::sys::Program::ExecuteAndWait(Ubiviz, &args[0],0,0,0,0,&ErrMsg)) {
762     llvm::errs() << "Error viewing graph: " << ErrMsg << "\n";
763   }
764 
765   // Delete the directory.
766   Dir.eraseFromDisk(true);
767 }
768