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 #include "clang/StaticAnalyzer/Frontend/AnalysisConsumer.h"
15 #include "ModelInjector.h"
16 #include "clang/AST/Decl.h"
17 #include "clang/AST/DeclCXX.h"
18 #include "clang/AST/DeclObjC.h"
19 #include "clang/AST/RecursiveASTVisitor.h"
20 #include "clang/Analysis/Analyses/LiveVariables.h"
21 #include "clang/Analysis/CFG.h"
22 #include "clang/Analysis/CallGraph.h"
23 #include "clang/Analysis/CodeInjector.h"
24 #include "clang/Basic/SourceManager.h"
25 #include "clang/Frontend/CompilerInstance.h"
26 #include "clang/Lex/Preprocessor.h"
27 #include "clang/StaticAnalyzer/Checkers/LocalCheckers.h"
28 #include "clang/StaticAnalyzer/Core/AnalyzerOptions.h"
29 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
30 #include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
31 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
32 #include "clang/StaticAnalyzer/Core/PathDiagnosticConsumers.h"
33 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
34 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
35 #include "clang/StaticAnalyzer/Frontend/CheckerRegistration.h"
36 #include "llvm/ADT/PostOrderIterator.h"
37 #include "llvm/ADT/Statistic.h"
38 #include "llvm/Support/FileSystem.h"
39 #include "llvm/Support/Path.h"
40 #include "llvm/Support/Program.h"
41 #include "llvm/Support/Timer.h"
42 #include "llvm/Support/raw_ostream.h"
43 #include <memory>
44 #include <queue>
45 #include <utility>
46 
47 using namespace clang;
48 using namespace ento;
49 
50 #define DEBUG_TYPE "AnalysisConsumer"
51 
52 static std::unique_ptr<ExplodedNode::Auditor> CreateUbiViz();
53 
54 STATISTIC(NumFunctionTopLevel, "The # of functions at top level.");
55 STATISTIC(NumFunctionsAnalyzed,
56                       "The # of functions and blocks analyzed (as top level "
57                       "with inlining turned on).");
58 STATISTIC(NumBlocksInAnalyzedFunctions,
59                       "The # of basic blocks in the analyzed functions.");
60 STATISTIC(PercentReachableBlocks, "The % of reachable basic blocks.");
61 STATISTIC(MaxCFGSize, "The maximum number of basic blocks in a function.");
62 
63 //===----------------------------------------------------------------------===//
64 // Special PathDiagnosticConsumers.
65 //===----------------------------------------------------------------------===//
66 
67 void ento::createPlistHTMLDiagnosticConsumer(AnalyzerOptions &AnalyzerOpts,
68                                              PathDiagnosticConsumers &C,
69                                              const std::string &prefix,
70                                              const Preprocessor &PP) {
71   createHTMLDiagnosticConsumer(AnalyzerOpts, C,
72                                llvm::sys::path::parent_path(prefix), PP);
73   createPlistDiagnosticConsumer(AnalyzerOpts, C, prefix, PP);
74 }
75 
76 void ento::createTextPathDiagnosticConsumer(AnalyzerOptions &AnalyzerOpts,
77                                             PathDiagnosticConsumers &C,
78                                             const std::string &Prefix,
79                                             const clang::Preprocessor &PP) {
80   llvm_unreachable("'text' consumer should be enabled on ClangDiags");
81 }
82 
83 namespace {
84 class ClangDiagPathDiagConsumer : public PathDiagnosticConsumer {
85   DiagnosticsEngine &Diag;
86   bool IncludePath;
87 public:
88   ClangDiagPathDiagConsumer(DiagnosticsEngine &Diag)
89     : Diag(Diag), IncludePath(false) {}
90   ~ClangDiagPathDiagConsumer() override {}
91   StringRef getName() const override { return "ClangDiags"; }
92 
93   bool supportsLogicalOpControlFlow() const override { return true; }
94   bool supportsCrossFileDiagnostics() const override { return true; }
95 
96   PathGenerationScheme getGenerationScheme() const override {
97     return IncludePath ? Minimal : None;
98   }
99 
100   void enablePaths() {
101     IncludePath = true;
102   }
103 
104   void FlushDiagnosticsImpl(std::vector<const PathDiagnostic *> &Diags,
105                             FilesMade *filesMade) override {
106     unsigned WarnID = Diag.getCustomDiagID(DiagnosticsEngine::Warning, "%0");
107     unsigned NoteID = Diag.getCustomDiagID(DiagnosticsEngine::Note, "%0");
108 
109     for (std::vector<const PathDiagnostic*>::iterator I = Diags.begin(),
110          E = Diags.end(); I != E; ++I) {
111       const PathDiagnostic *PD = *I;
112       SourceLocation WarnLoc = PD->getLocation().asLocation();
113       Diag.Report(WarnLoc, WarnID) << PD->getShortDescription()
114                                    << PD->path.back()->getRanges();
115 
116       if (!IncludePath)
117         continue;
118 
119       PathPieces FlatPath = PD->path.flatten(/*ShouldFlattenMacros=*/true);
120       for (PathPieces::const_iterator PI = FlatPath.begin(),
121                                       PE = FlatPath.end();
122            PI != PE; ++PI) {
123         SourceLocation NoteLoc = (*PI)->getLocation().asLocation();
124         Diag.Report(NoteLoc, NoteID) << (*PI)->getString()
125                                      << (*PI)->getRanges();
126       }
127     }
128   }
129 };
130 } // end anonymous namespace
131 
132 //===----------------------------------------------------------------------===//
133 // AnalysisConsumer declaration.
134 //===----------------------------------------------------------------------===//
135 
136 namespace {
137 
138 class AnalysisConsumer : public AnalysisASTConsumer,
139                          public RecursiveASTVisitor<AnalysisConsumer> {
140   enum {
141     AM_None = 0,
142     AM_Syntax = 0x1,
143     AM_Path = 0x2
144   };
145   typedef unsigned AnalysisMode;
146 
147   /// Mode of the analyzes while recursively visiting Decls.
148   AnalysisMode RecVisitorMode;
149   /// Bug Reporter to use while recursively visiting Decls.
150   BugReporter *RecVisitorBR;
151 
152 public:
153   ASTContext *Ctx;
154   const Preprocessor &PP;
155   const std::string OutDir;
156   AnalyzerOptionsRef Opts;
157   ArrayRef<std::string> Plugins;
158   CodeInjector *Injector;
159 
160   /// \brief Stores the declarations from the local translation unit.
161   /// Note, we pre-compute the local declarations at parse time as an
162   /// optimization to make sure we do not deserialize everything from disk.
163   /// The local declaration to all declarations ratio might be very small when
164   /// working with a PCH file.
165   SetOfDecls LocalTUDecls;
166 
167   // Set of PathDiagnosticConsumers.  Owned by AnalysisManager.
168   PathDiagnosticConsumers PathConsumers;
169 
170   StoreManagerCreator CreateStoreMgr;
171   ConstraintManagerCreator CreateConstraintMgr;
172 
173   std::unique_ptr<CheckerManager> checkerMgr;
174   std::unique_ptr<AnalysisManager> Mgr;
175 
176   /// Time the analyzes time of each translation unit.
177   static llvm::Timer* TUTotalTimer;
178 
179   /// The information about analyzed functions shared throughout the
180   /// translation unit.
181   FunctionSummariesTy FunctionSummaries;
182 
183   AnalysisConsumer(const Preprocessor &pp, const std::string &outdir,
184                    AnalyzerOptionsRef opts, ArrayRef<std::string> plugins,
185                    CodeInjector *injector)
186       : RecVisitorMode(0), RecVisitorBR(nullptr), Ctx(nullptr), PP(pp),
187         OutDir(outdir), Opts(std::move(opts)), Plugins(plugins),
188         Injector(injector) {
189     DigestAnalyzerOptions();
190     if (Opts->PrintStats) {
191       llvm::EnableStatistics();
192       TUTotalTimer = new llvm::Timer("Analyzer Total Time");
193     }
194   }
195 
196   ~AnalysisConsumer() override {
197     if (Opts->PrintStats)
198       delete TUTotalTimer;
199   }
200 
201   void DigestAnalyzerOptions() {
202     if (Opts->AnalysisDiagOpt != PD_NONE) {
203       // Create the PathDiagnosticConsumer.
204       ClangDiagPathDiagConsumer *clangDiags =
205           new ClangDiagPathDiagConsumer(PP.getDiagnostics());
206       PathConsumers.push_back(clangDiags);
207 
208       if (Opts->AnalysisDiagOpt == PD_TEXT) {
209         clangDiags->enablePaths();
210 
211       } else if (!OutDir.empty()) {
212         switch (Opts->AnalysisDiagOpt) {
213         default:
214 #define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATEFN)                    \
215   case PD_##NAME:                                                              \
216     CREATEFN(*Opts.get(), PathConsumers, OutDir, PP);                       \
217     break;
218 #include "clang/StaticAnalyzer/Core/Analyses.def"
219         }
220       }
221     }
222 
223     // Create the analyzer component creators.
224     switch (Opts->AnalysisStoreOpt) {
225     default:
226       llvm_unreachable("Unknown store manager.");
227 #define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATEFN)           \
228       case NAME##Model: CreateStoreMgr = CREATEFN; break;
229 #include "clang/StaticAnalyzer/Core/Analyses.def"
230     }
231 
232     switch (Opts->AnalysisConstraintsOpt) {
233     default:
234       llvm_unreachable("Unknown constraint manager.");
235 #define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATEFN)     \
236       case NAME##Model: CreateConstraintMgr = CREATEFN; break;
237 #include "clang/StaticAnalyzer/Core/Analyses.def"
238     }
239   }
240 
241   void DisplayFunction(const Decl *D, AnalysisMode Mode,
242                        ExprEngine::InliningModes IMode) {
243     if (!Opts->AnalyzerDisplayProgress)
244       return;
245 
246     SourceManager &SM = Mgr->getASTContext().getSourceManager();
247     PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
248     if (Loc.isValid()) {
249       llvm::errs() << "ANALYZE";
250 
251       if (Mode == AM_Syntax)
252         llvm::errs() << " (Syntax)";
253       else if (Mode == AM_Path) {
254         llvm::errs() << " (Path, ";
255         switch (IMode) {
256           case ExprEngine::Inline_Minimal:
257             llvm::errs() << " Inline_Minimal";
258             break;
259           case ExprEngine::Inline_Regular:
260             llvm::errs() << " Inline_Regular";
261             break;
262         }
263         llvm::errs() << ")";
264       }
265       else
266         assert(Mode == (AM_Syntax | AM_Path) && "Unexpected mode!");
267 
268       llvm::errs() << ": " << Loc.getFilename();
269       if (isa<FunctionDecl>(D) || isa<ObjCMethodDecl>(D)) {
270         const NamedDecl *ND = cast<NamedDecl>(D);
271         llvm::errs() << ' ' << ND->getQualifiedNameAsString() << '\n';
272       }
273       else if (isa<BlockDecl>(D)) {
274         llvm::errs() << ' ' << "block(line:" << Loc.getLine() << ",col:"
275                      << Loc.getColumn() << '\n';
276       }
277       else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
278         Selector S = MD->getSelector();
279         llvm::errs() << ' ' << S.getAsString();
280       }
281     }
282   }
283 
284   void Initialize(ASTContext &Context) override {
285     Ctx = &Context;
286     checkerMgr = createCheckerManager(*Opts, PP.getLangOpts(), Plugins,
287                                       PP.getDiagnostics());
288 
289     Mgr = llvm::make_unique<AnalysisManager>(
290         *Ctx, PP.getDiagnostics(), PP.getLangOpts(), PathConsumers,
291         CreateStoreMgr, CreateConstraintMgr, checkerMgr.get(), *Opts, Injector);
292   }
293 
294   /// \brief Store the top level decls in the set to be processed later on.
295   /// (Doing this pre-processing avoids deserialization of data from PCH.)
296   bool HandleTopLevelDecl(DeclGroupRef D) override;
297   void HandleTopLevelDeclInObjCContainer(DeclGroupRef D) override;
298 
299   void HandleTranslationUnit(ASTContext &C) override;
300 
301   /// \brief Determine which inlining mode should be used when this function is
302   /// analyzed. This allows to redefine the default inlining policies when
303   /// analyzing a given function.
304   ExprEngine::InliningModes
305     getInliningModeForFunction(const Decl *D, const SetOfConstDecls &Visited);
306 
307   /// \brief Build the call graph for all the top level decls of this TU and
308   /// use it to define the order in which the functions should be visited.
309   void HandleDeclsCallGraph(const unsigned LocalTUDeclsSize);
310 
311   /// \brief Run analyzes(syntax or path sensitive) on the given function.
312   /// \param Mode - determines if we are requesting syntax only or path
313   /// sensitive only analysis.
314   /// \param VisitedCallees - The output parameter, which is populated with the
315   /// set of functions which should be considered analyzed after analyzing the
316   /// given root function.
317   void HandleCode(Decl *D, AnalysisMode Mode,
318                   ExprEngine::InliningModes IMode = ExprEngine::Inline_Minimal,
319                   SetOfConstDecls *VisitedCallees = nullptr);
320 
321   void RunPathSensitiveChecks(Decl *D,
322                               ExprEngine::InliningModes IMode,
323                               SetOfConstDecls *VisitedCallees);
324   void ActionExprEngine(Decl *D, bool ObjCGCEnabled,
325                         ExprEngine::InliningModes IMode,
326                         SetOfConstDecls *VisitedCallees);
327 
328   /// Visitors for the RecursiveASTVisitor.
329   bool shouldWalkTypesOfTypeLocs() const { return false; }
330 
331   /// Handle callbacks for arbitrary Decls.
332   bool VisitDecl(Decl *D) {
333     AnalysisMode Mode = getModeForDecl(D, RecVisitorMode);
334     if (Mode & AM_Syntax)
335       checkerMgr->runCheckersOnASTDecl(D, *Mgr, *RecVisitorBR);
336     return true;
337   }
338 
339   bool VisitFunctionDecl(FunctionDecl *FD) {
340     IdentifierInfo *II = FD->getIdentifier();
341     if (II && II->getName().startswith("__inline"))
342       return true;
343 
344     // We skip function template definitions, as their semantics is
345     // only determined when they are instantiated.
346     if (FD->isThisDeclarationADefinition() &&
347         !FD->isDependentContext()) {
348       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
349       HandleCode(FD, RecVisitorMode);
350     }
351     return true;
352   }
353 
354   bool VisitObjCMethodDecl(ObjCMethodDecl *MD) {
355     if (MD->isThisDeclarationADefinition()) {
356       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
357       HandleCode(MD, RecVisitorMode);
358     }
359     return true;
360   }
361 
362   bool VisitBlockDecl(BlockDecl *BD) {
363     if (BD->hasBody()) {
364       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
365       // Since we skip function template definitions, we should skip blocks
366       // declared in those functions as well.
367       if (!BD->isDependentContext()) {
368         HandleCode(BD, RecVisitorMode);
369       }
370     }
371     return true;
372   }
373 
374   void AddDiagnosticConsumer(PathDiagnosticConsumer *Consumer) override {
375     PathConsumers.push_back(Consumer);
376   }
377 
378 private:
379   void storeTopLevelDecls(DeclGroupRef DG);
380 
381   /// \brief Check if we should skip (not analyze) the given function.
382   AnalysisMode getModeForDecl(Decl *D, AnalysisMode Mode);
383 
384 };
385 } // end anonymous namespace
386 
387 
388 //===----------------------------------------------------------------------===//
389 // AnalysisConsumer implementation.
390 //===----------------------------------------------------------------------===//
391 llvm::Timer* AnalysisConsumer::TUTotalTimer = nullptr;
392 
393 bool AnalysisConsumer::HandleTopLevelDecl(DeclGroupRef DG) {
394   storeTopLevelDecls(DG);
395   return true;
396 }
397 
398 void AnalysisConsumer::HandleTopLevelDeclInObjCContainer(DeclGroupRef DG) {
399   storeTopLevelDecls(DG);
400 }
401 
402 void AnalysisConsumer::storeTopLevelDecls(DeclGroupRef DG) {
403   for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I) {
404 
405     // Skip ObjCMethodDecl, wait for the objc container to avoid
406     // analyzing twice.
407     if (isa<ObjCMethodDecl>(*I))
408       continue;
409 
410     LocalTUDecls.push_back(*I);
411   }
412 }
413 
414 static bool shouldSkipFunction(const Decl *D,
415                                const SetOfConstDecls &Visited,
416                                const SetOfConstDecls &VisitedAsTopLevel) {
417   if (VisitedAsTopLevel.count(D))
418     return true;
419 
420   // We want to re-analyse the functions as top level in the following cases:
421   // - The 'init' methods should be reanalyzed because
422   //   ObjCNonNilReturnValueChecker assumes that '[super init]' never returns
423   //   'nil' and unless we analyze the 'init' functions as top level, we will
424   //   not catch errors within defensive code.
425   // - We want to reanalyze all ObjC methods as top level to report Retain
426   //   Count naming convention errors more aggressively.
427   if (isa<ObjCMethodDecl>(D))
428     return false;
429 
430   // Otherwise, if we visited the function before, do not reanalyze it.
431   return Visited.count(D);
432 }
433 
434 ExprEngine::InliningModes
435 AnalysisConsumer::getInliningModeForFunction(const Decl *D,
436                                              const SetOfConstDecls &Visited) {
437   // We want to reanalyze all ObjC methods as top level to report Retain
438   // Count naming convention errors more aggressively. But we should tune down
439   // inlining when reanalyzing an already inlined function.
440   if (Visited.count(D)) {
441     assert(isa<ObjCMethodDecl>(D) &&
442            "We are only reanalyzing ObjCMethods.");
443     const ObjCMethodDecl *ObjCM = cast<ObjCMethodDecl>(D);
444     if (ObjCM->getMethodFamily() != OMF_init)
445       return ExprEngine::Inline_Minimal;
446   }
447 
448   return ExprEngine::Inline_Regular;
449 }
450 
451 void AnalysisConsumer::HandleDeclsCallGraph(const unsigned LocalTUDeclsSize) {
452   // Build the Call Graph by adding all the top level declarations to the graph.
453   // Note: CallGraph can trigger deserialization of more items from a pch
454   // (though HandleInterestingDecl); triggering additions to LocalTUDecls.
455   // We rely on random access to add the initially processed Decls to CG.
456   CallGraph CG;
457   for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) {
458     CG.addToCallGraph(LocalTUDecls[i]);
459   }
460 
461   // Walk over all of the call graph nodes in topological order, so that we
462   // analyze parents before the children. Skip the functions inlined into
463   // the previously processed functions. Use external Visited set to identify
464   // inlined functions. The topological order allows the "do not reanalyze
465   // previously inlined function" performance heuristic to be triggered more
466   // often.
467   SetOfConstDecls Visited;
468   SetOfConstDecls VisitedAsTopLevel;
469   llvm::ReversePostOrderTraversal<clang::CallGraph*> RPOT(&CG);
470   for (llvm::ReversePostOrderTraversal<clang::CallGraph*>::rpo_iterator
471          I = RPOT.begin(), E = RPOT.end(); I != E; ++I) {
472     NumFunctionTopLevel++;
473 
474     CallGraphNode *N = *I;
475     Decl *D = N->getDecl();
476 
477     // Skip the abstract root node.
478     if (!D)
479       continue;
480 
481     // Skip the functions which have been processed already or previously
482     // inlined.
483     if (shouldSkipFunction(D, Visited, VisitedAsTopLevel))
484       continue;
485 
486     // Analyze the function.
487     SetOfConstDecls VisitedCallees;
488 
489     HandleCode(D, AM_Path, getInliningModeForFunction(D, Visited),
490                (Mgr->options.InliningMode == All ? nullptr : &VisitedCallees));
491 
492     // Add the visited callees to the global visited set.
493     for (const Decl *Callee : VisitedCallees)
494       // Decls from CallGraph are already canonical. But Decls coming from
495       // CallExprs may be not. We should canonicalize them manually.
496       Visited.insert(isa<ObjCMethodDecl>(Callee) ? Callee
497                                                  : Callee->getCanonicalDecl());
498     VisitedAsTopLevel.insert(D);
499   }
500 }
501 
502 void AnalysisConsumer::HandleTranslationUnit(ASTContext &C) {
503   // Don't run the actions if an error has occurred with parsing the file.
504   DiagnosticsEngine &Diags = PP.getDiagnostics();
505   if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred())
506     return;
507 
508   // Don't analyze if the user explicitly asked for no checks to be performed
509   // on this file.
510   if (Opts->DisableAllChecks)
511     return;
512 
513   {
514     if (TUTotalTimer) TUTotalTimer->startTimer();
515 
516     // Introduce a scope to destroy BR before Mgr.
517     BugReporter BR(*Mgr);
518     TranslationUnitDecl *TU = C.getTranslationUnitDecl();
519     checkerMgr->runCheckersOnASTDecl(TU, *Mgr, BR);
520 
521     // Run the AST-only checks using the order in which functions are defined.
522     // If inlining is not turned on, use the simplest function order for path
523     // sensitive analyzes as well.
524     RecVisitorMode = AM_Syntax;
525     if (!Mgr->shouldInlineCall())
526       RecVisitorMode |= AM_Path;
527     RecVisitorBR = &BR;
528 
529     // Process all the top level declarations.
530     //
531     // Note: TraverseDecl may modify LocalTUDecls, but only by appending more
532     // entries.  Thus we don't use an iterator, but rely on LocalTUDecls
533     // random access.  By doing so, we automatically compensate for iterators
534     // possibly being invalidated, although this is a bit slower.
535     const unsigned LocalTUDeclsSize = LocalTUDecls.size();
536     for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) {
537       TraverseDecl(LocalTUDecls[i]);
538     }
539 
540     if (Mgr->shouldInlineCall())
541       HandleDeclsCallGraph(LocalTUDeclsSize);
542 
543     // After all decls handled, run checkers on the entire TranslationUnit.
544     checkerMgr->runCheckersOnEndOfTranslationUnit(TU, *Mgr, BR);
545 
546     RecVisitorBR = nullptr;
547   }
548 
549   // Explicitly destroy the PathDiagnosticConsumer.  This will flush its output.
550   // FIXME: This should be replaced with something that doesn't rely on
551   // side-effects in PathDiagnosticConsumer's destructor. This is required when
552   // used with option -disable-free.
553   Mgr.reset();
554 
555   if (TUTotalTimer) TUTotalTimer->stopTimer();
556 
557   // Count how many basic blocks we have not covered.
558   NumBlocksInAnalyzedFunctions = FunctionSummaries.getTotalNumBasicBlocks();
559   if (NumBlocksInAnalyzedFunctions > 0)
560     PercentReachableBlocks =
561       (FunctionSummaries.getTotalNumVisitedBasicBlocks() * 100) /
562         NumBlocksInAnalyzedFunctions;
563 
564 }
565 
566 static std::string getFunctionName(const Decl *D) {
567   if (const ObjCMethodDecl *ID = dyn_cast<ObjCMethodDecl>(D)) {
568     return ID->getSelector().getAsString();
569   }
570   if (const FunctionDecl *ND = dyn_cast<FunctionDecl>(D)) {
571     IdentifierInfo *II = ND->getIdentifier();
572     if (II)
573       return II->getName();
574   }
575   return "";
576 }
577 
578 AnalysisConsumer::AnalysisMode
579 AnalysisConsumer::getModeForDecl(Decl *D, AnalysisMode Mode) {
580   if (!Opts->AnalyzeSpecificFunction.empty() &&
581       getFunctionName(D) != Opts->AnalyzeSpecificFunction)
582     return AM_None;
583 
584   // Unless -analyze-all is specified, treat decls differently depending on
585   // where they came from:
586   // - Main source file: run both path-sensitive and non-path-sensitive checks.
587   // - Header files: run non-path-sensitive checks only.
588   // - System headers: don't run any checks.
589   SourceManager &SM = Ctx->getSourceManager();
590   const Stmt *Body = D->getBody();
591   SourceLocation SL = Body ? Body->getLocStart() : D->getLocation();
592   SL = SM.getExpansionLoc(SL);
593 
594   if (!Opts->AnalyzeAll && !SM.isWrittenInMainFile(SL)) {
595     if (SL.isInvalid() || SM.isInSystemHeader(SL))
596       return AM_None;
597     return Mode & ~AM_Path;
598   }
599 
600   return Mode;
601 }
602 
603 void AnalysisConsumer::HandleCode(Decl *D, AnalysisMode Mode,
604                                   ExprEngine::InliningModes IMode,
605                                   SetOfConstDecls *VisitedCallees) {
606   if (!D->hasBody())
607     return;
608   Mode = getModeForDecl(D, Mode);
609   if (Mode == AM_None)
610     return;
611 
612   DisplayFunction(D, Mode, IMode);
613   CFG *DeclCFG = Mgr->getCFG(D);
614   if (DeclCFG) {
615     unsigned CFGSize = DeclCFG->size();
616     MaxCFGSize = MaxCFGSize < CFGSize ? CFGSize : MaxCFGSize;
617   }
618 
619   // Clear the AnalysisManager of old AnalysisDeclContexts.
620   Mgr->ClearContexts();
621   BugReporter BR(*Mgr);
622 
623   if (Mode & AM_Syntax)
624     checkerMgr->runCheckersOnASTBody(D, *Mgr, BR);
625   if ((Mode & AM_Path) && checkerMgr->hasPathSensitiveCheckers()) {
626     RunPathSensitiveChecks(D, IMode, VisitedCallees);
627     if (IMode != ExprEngine::Inline_Minimal)
628       NumFunctionsAnalyzed++;
629   }
630 }
631 
632 //===----------------------------------------------------------------------===//
633 // Path-sensitive checking.
634 //===----------------------------------------------------------------------===//
635 
636 void AnalysisConsumer::ActionExprEngine(Decl *D, bool ObjCGCEnabled,
637                                         ExprEngine::InliningModes IMode,
638                                         SetOfConstDecls *VisitedCallees) {
639   // Construct the analysis engine.  First check if the CFG is valid.
640   // FIXME: Inter-procedural analysis will need to handle invalid CFGs.
641   if (!Mgr->getCFG(D))
642     return;
643 
644   // See if the LiveVariables analysis scales.
645   if (!Mgr->getAnalysisDeclContext(D)->getAnalysis<RelaxedLiveVariables>())
646     return;
647 
648   ExprEngine Eng(*Mgr, ObjCGCEnabled, VisitedCallees, &FunctionSummaries,IMode);
649 
650   // Set the graph auditor.
651   std::unique_ptr<ExplodedNode::Auditor> Auditor;
652   if (Mgr->options.visualizeExplodedGraphWithUbiGraph) {
653     Auditor = CreateUbiViz();
654     ExplodedNode::SetAuditor(Auditor.get());
655   }
656 
657   // Execute the worklist algorithm.
658   Eng.ExecuteWorkList(Mgr->getAnalysisDeclContextManager().getStackFrame(D),
659                       Mgr->options.getMaxNodesPerTopLevelFunction());
660 
661   // Release the auditor (if any) so that it doesn't monitor the graph
662   // created BugReporter.
663   ExplodedNode::SetAuditor(nullptr);
664 
665   // Visualize the exploded graph.
666   if (Mgr->options.visualizeExplodedGraphWithGraphViz)
667     Eng.ViewGraph(Mgr->options.TrimGraph);
668 
669   // Display warnings.
670   Eng.getBugReporter().FlushReports();
671 }
672 
673 void AnalysisConsumer::RunPathSensitiveChecks(Decl *D,
674                                               ExprEngine::InliningModes IMode,
675                                               SetOfConstDecls *Visited) {
676 
677   switch (Mgr->getLangOpts().getGC()) {
678   case LangOptions::NonGC:
679     ActionExprEngine(D, false, IMode, Visited);
680     break;
681 
682   case LangOptions::GCOnly:
683     ActionExprEngine(D, true, IMode, Visited);
684     break;
685 
686   case LangOptions::HybridGC:
687     ActionExprEngine(D, false, IMode, Visited);
688     ActionExprEngine(D, true, IMode, Visited);
689     break;
690   }
691 }
692 
693 //===----------------------------------------------------------------------===//
694 // AnalysisConsumer creation.
695 //===----------------------------------------------------------------------===//
696 
697 std::unique_ptr<AnalysisASTConsumer>
698 ento::CreateAnalysisConsumer(CompilerInstance &CI) {
699   // Disable the effects of '-Werror' when using the AnalysisConsumer.
700   CI.getPreprocessor().getDiagnostics().setWarningsAsErrors(false);
701 
702   AnalyzerOptionsRef analyzerOpts = CI.getAnalyzerOpts();
703   bool hasModelPath = analyzerOpts->Config.count("model-path") > 0;
704 
705   return llvm::make_unique<AnalysisConsumer>(
706       CI.getPreprocessor(), CI.getFrontendOpts().OutputFile, analyzerOpts,
707       CI.getFrontendOpts().Plugins,
708       hasModelPath ? new ModelInjector(CI) : nullptr);
709 }
710 
711 //===----------------------------------------------------------------------===//
712 // Ubigraph Visualization.  FIXME: Move to separate file.
713 //===----------------------------------------------------------------------===//
714 
715 namespace {
716 
717 class UbigraphViz : public ExplodedNode::Auditor {
718   std::unique_ptr<raw_ostream> Out;
719   std::string Filename;
720   unsigned Cntr;
721 
722   typedef llvm::DenseMap<void*,unsigned> VMap;
723   VMap M;
724 
725 public:
726   UbigraphViz(std::unique_ptr<raw_ostream> Out, StringRef Filename);
727 
728   ~UbigraphViz() override;
729 
730   void AddEdge(ExplodedNode *Src, ExplodedNode *Dst) override;
731 };
732 
733 } // end anonymous namespace
734 
735 static std::unique_ptr<ExplodedNode::Auditor> CreateUbiViz() {
736   SmallString<128> P;
737   int FD;
738   llvm::sys::fs::createTemporaryFile("llvm_ubi", "", FD, P);
739   llvm::errs() << "Writing '" << P << "'.\n";
740 
741   auto Stream = llvm::make_unique<llvm::raw_fd_ostream>(FD, true);
742 
743   return llvm::make_unique<UbigraphViz>(std::move(Stream), P);
744 }
745 
746 void UbigraphViz::AddEdge(ExplodedNode *Src, ExplodedNode *Dst) {
747 
748   assert (Src != Dst && "Self-edges are not allowed.");
749 
750   // Lookup the Src.  If it is a new node, it's a root.
751   VMap::iterator SrcI= M.find(Src);
752   unsigned SrcID;
753 
754   if (SrcI == M.end()) {
755     M[Src] = SrcID = Cntr++;
756     *Out << "('vertex', " << SrcID << ", ('color','#00ff00'))\n";
757   }
758   else
759     SrcID = SrcI->second;
760 
761   // Lookup the Dst.
762   VMap::iterator DstI= M.find(Dst);
763   unsigned DstID;
764 
765   if (DstI == M.end()) {
766     M[Dst] = DstID = Cntr++;
767     *Out << "('vertex', " << DstID << ")\n";
768   }
769   else {
770     // We have hit DstID before.  Change its style to reflect a cache hit.
771     DstID = DstI->second;
772     *Out << "('change_vertex_style', " << DstID << ", 1)\n";
773   }
774 
775   // Add the edge.
776   *Out << "('edge', " << SrcID << ", " << DstID
777        << ", ('arrow','true'), ('oriented', 'true'))\n";
778 }
779 
780 UbigraphViz::UbigraphViz(std::unique_ptr<raw_ostream> OutStream,
781                          StringRef Filename)
782     : Out(std::move(OutStream)), Filename(Filename), Cntr(0) {
783 
784   *Out << "('vertex_style_attribute', 0, ('shape', 'icosahedron'))\n";
785   *Out << "('vertex_style', 1, 0, ('shape', 'sphere'), ('color', '#ffcc66'),"
786           " ('size', '1.5'))\n";
787 }
788 
789 UbigraphViz::~UbigraphViz() {
790   Out.reset();
791   llvm::errs() << "Running 'ubiviz' program... ";
792   std::string ErrMsg;
793   std::string Ubiviz;
794   if (auto Path = llvm::sys::findProgramByName("ubiviz"))
795     Ubiviz = *Path;
796   const char *args[] = {Ubiviz.c_str(), Filename.c_str(), nullptr};
797 
798   if (llvm::sys::ExecuteAndWait(Ubiviz, &args[0], nullptr, nullptr, 0, 0,
799                                 &ErrMsg)) {
800     llvm::errs() << "Error viewing graph: " << ErrMsg << "\n";
801   }
802 
803   // Delete the file.
804   llvm::sys::fs::remove(Filename);
805 }
806