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/CrossTU/CrossTranslationUnit.h"
26 #include "clang/Frontend/CompilerInstance.h"
27 #include "clang/Lex/Preprocessor.h"
28 #include "clang/StaticAnalyzer/Checkers/LocalCheckers.h"
29 #include "clang/StaticAnalyzer/Core/AnalyzerOptions.h"
30 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
31 #include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
32 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
33 #include "clang/StaticAnalyzer/Core/PathDiagnosticConsumers.h"
34 #include "clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h"
35 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
36 #include "clang/StaticAnalyzer/Frontend/CheckerRegistration.h"
37 #include "llvm/ADT/PostOrderIterator.h"
38 #include "llvm/ADT/Statistic.h"
39 #include "llvm/Support/FileSystem.h"
40 #include "llvm/Support/Path.h"
41 #include "llvm/Support/Program.h"
42 #include "llvm/Support/Timer.h"
43 #include "llvm/Support/raw_ostream.h"
44 #include <memory>
45 #include <queue>
46 #include <utility>
47 
48 using namespace clang;
49 using namespace ento;
50 
51 #define DEBUG_TYPE "AnalysisConsumer"
52 
53 STATISTIC(NumFunctionTopLevel, "The # of functions at top level.");
54 STATISTIC(NumFunctionsAnalyzed,
55                       "The # of functions and blocks analyzed (as top level "
56                       "with inlining turned on).");
57 STATISTIC(NumBlocksInAnalyzedFunctions,
58                       "The # of basic blocks in the analyzed functions.");
59 STATISTIC(NumVisitedBlocksInAnalyzedFunctions,
60           "The # of visited basic blocks in the analyzed functions.");
61 STATISTIC(PercentReachableBlocks, "The % of reachable basic blocks.");
62 STATISTIC(MaxCFGSize, "The maximum number of basic blocks in a function.");
63 
64 //===----------------------------------------------------------------------===//
65 // Special PathDiagnosticConsumers.
66 //===----------------------------------------------------------------------===//
67 
createPlistHTMLDiagnosticConsumer(AnalyzerOptions & AnalyzerOpts,PathDiagnosticConsumers & C,const std::string & prefix,const Preprocessor & PP)68 void ento::createPlistHTMLDiagnosticConsumer(AnalyzerOptions &AnalyzerOpts,
69                                              PathDiagnosticConsumers &C,
70                                              const std::string &prefix,
71                                              const Preprocessor &PP) {
72   createHTMLDiagnosticConsumer(AnalyzerOpts, C,
73                                llvm::sys::path::parent_path(prefix), PP);
74   createPlistMultiFileDiagnosticConsumer(AnalyzerOpts, C, prefix, PP);
75 }
76 
createTextPathDiagnosticConsumer(AnalyzerOptions & AnalyzerOpts,PathDiagnosticConsumers & C,const std::string & Prefix,const clang::Preprocessor & PP)77 void ento::createTextPathDiagnosticConsumer(AnalyzerOptions &AnalyzerOpts,
78                                             PathDiagnosticConsumers &C,
79                                             const std::string &Prefix,
80                                             const clang::Preprocessor &PP) {
81   llvm_unreachable("'text' consumer should be enabled on ClangDiags");
82 }
83 
84 namespace {
85 class ClangDiagPathDiagConsumer : public PathDiagnosticConsumer {
86   DiagnosticsEngine &Diag;
87   bool IncludePath;
88 public:
ClangDiagPathDiagConsumer(DiagnosticsEngine & Diag)89   ClangDiagPathDiagConsumer(DiagnosticsEngine &Diag)
90     : Diag(Diag), IncludePath(false) {}
~ClangDiagPathDiagConsumer()91   ~ClangDiagPathDiagConsumer() override {}
getName() const92   StringRef getName() const override { return "ClangDiags"; }
93 
supportsLogicalOpControlFlow() const94   bool supportsLogicalOpControlFlow() const override { return true; }
supportsCrossFileDiagnostics() const95   bool supportsCrossFileDiagnostics() const override { return true; }
96 
getGenerationScheme() const97   PathGenerationScheme getGenerationScheme() const override {
98     return IncludePath ? Minimal : None;
99   }
100 
enablePaths()101   void enablePaths() {
102     IncludePath = true;
103   }
104 
FlushDiagnosticsImpl(std::vector<const PathDiagnostic * > & Diags,FilesMade * filesMade)105   void FlushDiagnosticsImpl(std::vector<const PathDiagnostic *> &Diags,
106                             FilesMade *filesMade) override {
107     unsigned WarnID = Diag.getCustomDiagID(DiagnosticsEngine::Warning, "%0");
108     unsigned NoteID = Diag.getCustomDiagID(DiagnosticsEngine::Note, "%0");
109 
110     for (std::vector<const PathDiagnostic*>::iterator I = Diags.begin(),
111          E = Diags.end(); I != E; ++I) {
112       const PathDiagnostic *PD = *I;
113       SourceLocation WarnLoc = PD->getLocation().asLocation();
114       Diag.Report(WarnLoc, WarnID) << PD->getShortDescription()
115                                    << PD->path.back()->getRanges();
116 
117       // First, add extra notes, even if paths should not be included.
118       for (const auto &Piece : PD->path) {
119         if (!isa<PathDiagnosticNotePiece>(Piece.get()))
120           continue;
121 
122         SourceLocation NoteLoc = Piece->getLocation().asLocation();
123         Diag.Report(NoteLoc, NoteID) << Piece->getString()
124                                      << Piece->getRanges();
125       }
126 
127       if (!IncludePath)
128         continue;
129 
130       // Then, add the path notes if necessary.
131       PathPieces FlatPath = PD->path.flatten(/*ShouldFlattenMacros=*/true);
132       for (const auto &Piece : FlatPath) {
133         if (isa<PathDiagnosticNotePiece>(Piece.get()))
134           continue;
135 
136         SourceLocation NoteLoc = Piece->getLocation().asLocation();
137         Diag.Report(NoteLoc, NoteID) << Piece->getString()
138                                      << Piece->getRanges();
139       }
140     }
141   }
142 };
143 } // end anonymous namespace
144 
145 //===----------------------------------------------------------------------===//
146 // AnalysisConsumer declaration.
147 //===----------------------------------------------------------------------===//
148 
149 namespace {
150 
151 class AnalysisConsumer : public AnalysisASTConsumer,
152                          public RecursiveASTVisitor<AnalysisConsumer> {
153   enum {
154     AM_None = 0,
155     AM_Syntax = 0x1,
156     AM_Path = 0x2
157   };
158   typedef unsigned AnalysisMode;
159 
160   /// Mode of the analyzes while recursively visiting Decls.
161   AnalysisMode RecVisitorMode;
162   /// Bug Reporter to use while recursively visiting Decls.
163   BugReporter *RecVisitorBR;
164 
165   std::vector<std::function<void(CheckerRegistry &)>> CheckerRegistrationFns;
166 
167 public:
168   ASTContext *Ctx;
169   const Preprocessor &PP;
170   const std::string OutDir;
171   AnalyzerOptionsRef Opts;
172   ArrayRef<std::string> Plugins;
173   CodeInjector *Injector;
174   cross_tu::CrossTranslationUnitContext CTU;
175 
176   /// Stores the declarations from the local translation unit.
177   /// Note, we pre-compute the local declarations at parse time as an
178   /// optimization to make sure we do not deserialize everything from disk.
179   /// The local declaration to all declarations ratio might be very small when
180   /// working with a PCH file.
181   SetOfDecls LocalTUDecls;
182 
183   // Set of PathDiagnosticConsumers.  Owned by AnalysisManager.
184   PathDiagnosticConsumers PathConsumers;
185 
186   StoreManagerCreator CreateStoreMgr;
187   ConstraintManagerCreator CreateConstraintMgr;
188 
189   std::unique_ptr<CheckerManager> checkerMgr;
190   std::unique_ptr<AnalysisManager> Mgr;
191 
192   /// Time the analyzes time of each translation unit.
193   std::unique_ptr<llvm::TimerGroup> AnalyzerTimers;
194   std::unique_ptr<llvm::Timer> TUTotalTimer;
195 
196   /// The information about analyzed functions shared throughout the
197   /// translation unit.
198   FunctionSummariesTy FunctionSummaries;
199 
AnalysisConsumer(CompilerInstance & CI,const std::string & outdir,AnalyzerOptionsRef opts,ArrayRef<std::string> plugins,CodeInjector * injector)200   AnalysisConsumer(CompilerInstance &CI, const std::string &outdir,
201                    AnalyzerOptionsRef opts, ArrayRef<std::string> plugins,
202                    CodeInjector *injector)
203       : RecVisitorMode(0), RecVisitorBR(nullptr), Ctx(nullptr),
204         PP(CI.getPreprocessor()), OutDir(outdir), Opts(std::move(opts)),
205         Plugins(plugins), Injector(injector), CTU(CI) {
206     DigestAnalyzerOptions();
207     if (Opts->PrintStats || Opts->ShouldSerializeStats) {
208       AnalyzerTimers = llvm::make_unique<llvm::TimerGroup>(
209           "analyzer", "Analyzer timers");
210       TUTotalTimer = llvm::make_unique<llvm::Timer>(
211           "time", "Analyzer total time", *AnalyzerTimers);
212       llvm::EnableStatistics(/* PrintOnExit= */ false);
213     }
214   }
215 
~AnalysisConsumer()216   ~AnalysisConsumer() override {
217     if (Opts->PrintStats) {
218       llvm::PrintStatistics();
219     }
220   }
221 
DigestAnalyzerOptions()222   void DigestAnalyzerOptions() {
223     if (Opts->AnalysisDiagOpt != PD_NONE) {
224       // Create the PathDiagnosticConsumer.
225       ClangDiagPathDiagConsumer *clangDiags =
226           new ClangDiagPathDiagConsumer(PP.getDiagnostics());
227       PathConsumers.push_back(clangDiags);
228 
229       if (Opts->AnalysisDiagOpt == PD_TEXT) {
230         clangDiags->enablePaths();
231 
232       } else if (!OutDir.empty()) {
233         switch (Opts->AnalysisDiagOpt) {
234         default:
235 #define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATEFN)                    \
236   case PD_##NAME:                                                              \
237     CREATEFN(*Opts.get(), PathConsumers, OutDir, PP);                       \
238     break;
239 #include "clang/StaticAnalyzer/Core/Analyses.def"
240         }
241       }
242     }
243 
244     // Create the analyzer component creators.
245     switch (Opts->AnalysisStoreOpt) {
246     default:
247       llvm_unreachable("Unknown store manager.");
248 #define ANALYSIS_STORE(NAME, CMDFLAG, DESC, CREATEFN)           \
249       case NAME##Model: CreateStoreMgr = CREATEFN; break;
250 #include "clang/StaticAnalyzer/Core/Analyses.def"
251     }
252 
253     switch (Opts->AnalysisConstraintsOpt) {
254     default:
255       llvm_unreachable("Unknown constraint manager.");
256 #define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATEFN)     \
257       case NAME##Model: CreateConstraintMgr = CREATEFN; break;
258 #include "clang/StaticAnalyzer/Core/Analyses.def"
259     }
260   }
261 
DisplayFunction(const Decl * D,AnalysisMode Mode,ExprEngine::InliningModes IMode)262   void DisplayFunction(const Decl *D, AnalysisMode Mode,
263                        ExprEngine::InliningModes IMode) {
264     if (!Opts->AnalyzerDisplayProgress)
265       return;
266 
267     SourceManager &SM = Mgr->getASTContext().getSourceManager();
268     PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
269     if (Loc.isValid()) {
270       llvm::errs() << "ANALYZE";
271 
272       if (Mode == AM_Syntax)
273         llvm::errs() << " (Syntax)";
274       else if (Mode == AM_Path) {
275         llvm::errs() << " (Path, ";
276         switch (IMode) {
277           case ExprEngine::Inline_Minimal:
278             llvm::errs() << " Inline_Minimal";
279             break;
280           case ExprEngine::Inline_Regular:
281             llvm::errs() << " Inline_Regular";
282             break;
283         }
284         llvm::errs() << ")";
285       }
286       else
287         assert(Mode == (AM_Syntax | AM_Path) && "Unexpected mode!");
288 
289       llvm::errs() << ": " << Loc.getFilename() << ' '
290                            << getFunctionName(D) << '\n';
291     }
292   }
293 
Initialize(ASTContext & Context)294   void Initialize(ASTContext &Context) override {
295     Ctx = &Context;
296     checkerMgr = createCheckerManager(
297         *Ctx, *Opts, Plugins, CheckerRegistrationFns, PP.getDiagnostics());
298 
299     Mgr = llvm::make_unique<AnalysisManager>(
300         *Ctx, PP.getDiagnostics(), PathConsumers, CreateStoreMgr,
301         CreateConstraintMgr, checkerMgr.get(), *Opts, Injector);
302   }
303 
304   /// Store the top level decls in the set to be processed later on.
305   /// (Doing this pre-processing avoids deserialization of data from PCH.)
306   bool HandleTopLevelDecl(DeclGroupRef D) override;
307   void HandleTopLevelDeclInObjCContainer(DeclGroupRef D) override;
308 
309   void HandleTranslationUnit(ASTContext &C) override;
310 
311   /// Determine which inlining mode should be used when this function is
312   /// analyzed. This allows to redefine the default inlining policies when
313   /// analyzing a given function.
314   ExprEngine::InliningModes
315     getInliningModeForFunction(const Decl *D, const SetOfConstDecls &Visited);
316 
317   /// Build the call graph for all the top level decls of this TU and
318   /// use it to define the order in which the functions should be visited.
319   void HandleDeclsCallGraph(const unsigned LocalTUDeclsSize);
320 
321   /// Run analyzes(syntax or path sensitive) on the given function.
322   /// \param Mode - determines if we are requesting syntax only or path
323   /// sensitive only analysis.
324   /// \param VisitedCallees - The output parameter, which is populated with the
325   /// set of functions which should be considered analyzed after analyzing the
326   /// given root function.
327   void HandleCode(Decl *D, AnalysisMode Mode,
328                   ExprEngine::InliningModes IMode = ExprEngine::Inline_Minimal,
329                   SetOfConstDecls *VisitedCallees = nullptr);
330 
331   void RunPathSensitiveChecks(Decl *D,
332                               ExprEngine::InliningModes IMode,
333                               SetOfConstDecls *VisitedCallees);
334 
335   /// Visitors for the RecursiveASTVisitor.
shouldWalkTypesOfTypeLocs() const336   bool shouldWalkTypesOfTypeLocs() const { return false; }
337 
338   /// Handle callbacks for arbitrary Decls.
VisitDecl(Decl * D)339   bool VisitDecl(Decl *D) {
340     AnalysisMode Mode = getModeForDecl(D, RecVisitorMode);
341     if (Mode & AM_Syntax)
342       checkerMgr->runCheckersOnASTDecl(D, *Mgr, *RecVisitorBR);
343     return true;
344   }
345 
VisitFunctionDecl(FunctionDecl * FD)346   bool VisitFunctionDecl(FunctionDecl *FD) {
347     IdentifierInfo *II = FD->getIdentifier();
348     if (II && II->getName().startswith("__inline"))
349       return true;
350 
351     // We skip function template definitions, as their semantics is
352     // only determined when they are instantiated.
353     if (FD->isThisDeclarationADefinition() &&
354         !FD->isDependentContext()) {
355       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
356       HandleCode(FD, RecVisitorMode);
357     }
358     return true;
359   }
360 
VisitObjCMethodDecl(ObjCMethodDecl * MD)361   bool VisitObjCMethodDecl(ObjCMethodDecl *MD) {
362     if (MD->isThisDeclarationADefinition()) {
363       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
364       HandleCode(MD, RecVisitorMode);
365     }
366     return true;
367   }
368 
VisitBlockDecl(BlockDecl * BD)369   bool VisitBlockDecl(BlockDecl *BD) {
370     if (BD->hasBody()) {
371       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
372       // Since we skip function template definitions, we should skip blocks
373       // declared in those functions as well.
374       if (!BD->isDependentContext()) {
375         HandleCode(BD, RecVisitorMode);
376       }
377     }
378     return true;
379   }
380 
AddDiagnosticConsumer(PathDiagnosticConsumer * Consumer)381   void AddDiagnosticConsumer(PathDiagnosticConsumer *Consumer) override {
382     PathConsumers.push_back(Consumer);
383   }
384 
AddCheckerRegistrationFn(std::function<void (CheckerRegistry &)> Fn)385   void AddCheckerRegistrationFn(std::function<void(CheckerRegistry&)> Fn) override {
386     CheckerRegistrationFns.push_back(std::move(Fn));
387   }
388 
389 private:
390   void storeTopLevelDecls(DeclGroupRef DG);
391   std::string getFunctionName(const Decl *D);
392 
393   /// Check if we should skip (not analyze) the given function.
394   AnalysisMode getModeForDecl(Decl *D, AnalysisMode Mode);
395   void runAnalysisOnTranslationUnit(ASTContext &C);
396 
397   /// Print \p S to stderr if \c Opts->AnalyzerDisplayProgress is set.
398   void reportAnalyzerProgress(StringRef S);
399 };
400 } // end anonymous namespace
401 
402 
403 //===----------------------------------------------------------------------===//
404 // AnalysisConsumer implementation.
405 //===----------------------------------------------------------------------===//
HandleTopLevelDecl(DeclGroupRef DG)406 bool AnalysisConsumer::HandleTopLevelDecl(DeclGroupRef DG) {
407   storeTopLevelDecls(DG);
408   return true;
409 }
410 
HandleTopLevelDeclInObjCContainer(DeclGroupRef DG)411 void AnalysisConsumer::HandleTopLevelDeclInObjCContainer(DeclGroupRef DG) {
412   storeTopLevelDecls(DG);
413 }
414 
storeTopLevelDecls(DeclGroupRef DG)415 void AnalysisConsumer::storeTopLevelDecls(DeclGroupRef DG) {
416   for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I) {
417 
418     // Skip ObjCMethodDecl, wait for the objc container to avoid
419     // analyzing twice.
420     if (isa<ObjCMethodDecl>(*I))
421       continue;
422 
423     LocalTUDecls.push_back(*I);
424   }
425 }
426 
shouldSkipFunction(const Decl * D,const SetOfConstDecls & Visited,const SetOfConstDecls & VisitedAsTopLevel)427 static bool shouldSkipFunction(const Decl *D,
428                                const SetOfConstDecls &Visited,
429                                const SetOfConstDecls &VisitedAsTopLevel) {
430   if (VisitedAsTopLevel.count(D))
431     return true;
432 
433   // We want to re-analyse the functions as top level in the following cases:
434   // - The 'init' methods should be reanalyzed because
435   //   ObjCNonNilReturnValueChecker assumes that '[super init]' never returns
436   //   'nil' and unless we analyze the 'init' functions as top level, we will
437   //   not catch errors within defensive code.
438   // - We want to reanalyze all ObjC methods as top level to report Retain
439   //   Count naming convention errors more aggressively.
440   if (isa<ObjCMethodDecl>(D))
441     return false;
442   // We also want to reanalyze all C++ copy and move assignment operators to
443   // separately check the two cases where 'this' aliases with the parameter and
444   // where it may not. (cplusplus.SelfAssignmentChecker)
445   if (const auto *MD = dyn_cast<CXXMethodDecl>(D)) {
446     if (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())
447       return false;
448   }
449 
450   // Otherwise, if we visited the function before, do not reanalyze it.
451   return Visited.count(D);
452 }
453 
454 ExprEngine::InliningModes
getInliningModeForFunction(const Decl * D,const SetOfConstDecls & Visited)455 AnalysisConsumer::getInliningModeForFunction(const Decl *D,
456                                              const SetOfConstDecls &Visited) {
457   // We want to reanalyze all ObjC methods as top level to report Retain
458   // Count naming convention errors more aggressively. But we should tune down
459   // inlining when reanalyzing an already inlined function.
460   if (Visited.count(D) && isa<ObjCMethodDecl>(D)) {
461     const ObjCMethodDecl *ObjCM = cast<ObjCMethodDecl>(D);
462     if (ObjCM->getMethodFamily() != OMF_init)
463       return ExprEngine::Inline_Minimal;
464   }
465 
466   return ExprEngine::Inline_Regular;
467 }
468 
HandleDeclsCallGraph(const unsigned LocalTUDeclsSize)469 void AnalysisConsumer::HandleDeclsCallGraph(const unsigned LocalTUDeclsSize) {
470   // Build the Call Graph by adding all the top level declarations to the graph.
471   // Note: CallGraph can trigger deserialization of more items from a pch
472   // (though HandleInterestingDecl); triggering additions to LocalTUDecls.
473   // We rely on random access to add the initially processed Decls to CG.
474   CallGraph CG;
475   for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) {
476     CG.addToCallGraph(LocalTUDecls[i]);
477   }
478 
479   // Walk over all of the call graph nodes in topological order, so that we
480   // analyze parents before the children. Skip the functions inlined into
481   // the previously processed functions. Use external Visited set to identify
482   // inlined functions. The topological order allows the "do not reanalyze
483   // previously inlined function" performance heuristic to be triggered more
484   // often.
485   SetOfConstDecls Visited;
486   SetOfConstDecls VisitedAsTopLevel;
487   llvm::ReversePostOrderTraversal<clang::CallGraph*> RPOT(&CG);
488   for (llvm::ReversePostOrderTraversal<clang::CallGraph*>::rpo_iterator
489          I = RPOT.begin(), E = RPOT.end(); I != E; ++I) {
490     NumFunctionTopLevel++;
491 
492     CallGraphNode *N = *I;
493     Decl *D = N->getDecl();
494 
495     // Skip the abstract root node.
496     if (!D)
497       continue;
498 
499     // Skip the functions which have been processed already or previously
500     // inlined.
501     if (shouldSkipFunction(D, Visited, VisitedAsTopLevel))
502       continue;
503 
504     // Analyze the function.
505     SetOfConstDecls VisitedCallees;
506 
507     HandleCode(D, AM_Path, getInliningModeForFunction(D, Visited),
508                (Mgr->options.InliningMode == All ? nullptr : &VisitedCallees));
509 
510     // Add the visited callees to the global visited set.
511     for (const Decl *Callee : VisitedCallees)
512       // Decls from CallGraph are already canonical. But Decls coming from
513       // CallExprs may be not. We should canonicalize them manually.
514       Visited.insert(isa<ObjCMethodDecl>(Callee) ? Callee
515                                                  : Callee->getCanonicalDecl());
516     VisitedAsTopLevel.insert(D);
517   }
518 }
519 
isBisonFile(ASTContext & C)520 static bool isBisonFile(ASTContext &C) {
521   const SourceManager &SM = C.getSourceManager();
522   FileID FID = SM.getMainFileID();
523   StringRef Buffer = SM.getBuffer(FID)->getBuffer();
524   if (Buffer.startswith("/* A Bison parser, made by"))
525     return true;
526   return false;
527 }
528 
runAnalysisOnTranslationUnit(ASTContext & C)529 void AnalysisConsumer::runAnalysisOnTranslationUnit(ASTContext &C) {
530   BugReporter BR(*Mgr);
531   TranslationUnitDecl *TU = C.getTranslationUnitDecl();
532   checkerMgr->runCheckersOnASTDecl(TU, *Mgr, BR);
533 
534   // Run the AST-only checks using the order in which functions are defined.
535   // If inlining is not turned on, use the simplest function order for path
536   // sensitive analyzes as well.
537   RecVisitorMode = AM_Syntax;
538   if (!Mgr->shouldInlineCall())
539     RecVisitorMode |= AM_Path;
540   RecVisitorBR = &BR;
541 
542   // Process all the top level declarations.
543   //
544   // Note: TraverseDecl may modify LocalTUDecls, but only by appending more
545   // entries.  Thus we don't use an iterator, but rely on LocalTUDecls
546   // random access.  By doing so, we automatically compensate for iterators
547   // possibly being invalidated, although this is a bit slower.
548   const unsigned LocalTUDeclsSize = LocalTUDecls.size();
549   for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) {
550     TraverseDecl(LocalTUDecls[i]);
551   }
552 
553   if (Mgr->shouldInlineCall())
554     HandleDeclsCallGraph(LocalTUDeclsSize);
555 
556   // After all decls handled, run checkers on the entire TranslationUnit.
557   checkerMgr->runCheckersOnEndOfTranslationUnit(TU, *Mgr, BR);
558 
559   RecVisitorBR = nullptr;
560 }
561 
reportAnalyzerProgress(StringRef S)562 void AnalysisConsumer::reportAnalyzerProgress(StringRef S) {
563   if (Opts->AnalyzerDisplayProgress)
564     llvm::errs() << S;
565 }
566 
HandleTranslationUnit(ASTContext & C)567 void AnalysisConsumer::HandleTranslationUnit(ASTContext &C) {
568 
569   // Don't run the actions if an error has occurred with parsing the file.
570   DiagnosticsEngine &Diags = PP.getDiagnostics();
571   if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred())
572     return;
573 
574   if (TUTotalTimer) TUTotalTimer->startTimer();
575 
576   if (isBisonFile(C)) {
577     reportAnalyzerProgress("Skipping bison-generated file\n");
578   } else if (Opts->DisableAllChecks) {
579 
580     // Don't analyze if the user explicitly asked for no checks to be performed
581     // on this file.
582     reportAnalyzerProgress("All checks are disabled using a supplied option\n");
583   } else {
584     // Otherwise, just run the analysis.
585     runAnalysisOnTranslationUnit(C);
586   }
587 
588   if (TUTotalTimer) TUTotalTimer->stopTimer();
589 
590   // Count how many basic blocks we have not covered.
591   NumBlocksInAnalyzedFunctions = FunctionSummaries.getTotalNumBasicBlocks();
592   NumVisitedBlocksInAnalyzedFunctions =
593       FunctionSummaries.getTotalNumVisitedBasicBlocks();
594   if (NumBlocksInAnalyzedFunctions > 0)
595     PercentReachableBlocks =
596       (FunctionSummaries.getTotalNumVisitedBasicBlocks() * 100) /
597         NumBlocksInAnalyzedFunctions;
598 
599   // Explicitly destroy the PathDiagnosticConsumer.  This will flush its output.
600   // FIXME: This should be replaced with something that doesn't rely on
601   // side-effects in PathDiagnosticConsumer's destructor. This is required when
602   // used with option -disable-free.
603   Mgr.reset();
604 }
605 
getFunctionName(const Decl * D)606 std::string AnalysisConsumer::getFunctionName(const Decl *D) {
607   std::string Str;
608   llvm::raw_string_ostream OS(Str);
609 
610   if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
611     OS << FD->getQualifiedNameAsString();
612 
613     // In C++, there are overloads.
614     if (Ctx->getLangOpts().CPlusPlus) {
615       OS << '(';
616       for (const auto &P : FD->parameters()) {
617         if (P != *FD->param_begin())
618           OS << ", ";
619         OS << P->getType().getAsString();
620       }
621       OS << ')';
622     }
623 
624   } else if (isa<BlockDecl>(D)) {
625     PresumedLoc Loc = Ctx->getSourceManager().getPresumedLoc(D->getLocation());
626 
627     if (Loc.isValid()) {
628       OS << "block (line: " << Loc.getLine() << ", col: " << Loc.getColumn()
629          << ')';
630     }
631 
632   } else if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)) {
633 
634     // FIXME: copy-pasted from CGDebugInfo.cpp.
635     OS << (OMD->isInstanceMethod() ? '-' : '+') << '[';
636     const DeclContext *DC = OMD->getDeclContext();
637     if (const auto *OID = dyn_cast<ObjCImplementationDecl>(DC)) {
638       OS << OID->getName();
639     } else if (const auto *OID = dyn_cast<ObjCInterfaceDecl>(DC)) {
640       OS << OID->getName();
641     } else if (const auto *OC = dyn_cast<ObjCCategoryDecl>(DC)) {
642       if (OC->IsClassExtension()) {
643         OS << OC->getClassInterface()->getName();
644       } else {
645         OS << OC->getIdentifier()->getNameStart() << '('
646            << OC->getIdentifier()->getNameStart() << ')';
647       }
648     } else if (const auto *OCD = dyn_cast<ObjCCategoryImplDecl>(DC)) {
649       OS << OCD->getClassInterface()->getName() << '('
650          << OCD->getName() << ')';
651     } else if (isa<ObjCProtocolDecl>(DC)) {
652       // We can extract the type of the class from the self pointer.
653       if (ImplicitParamDecl *SelfDecl = OMD->getSelfDecl()) {
654         QualType ClassTy =
655             cast<ObjCObjectPointerType>(SelfDecl->getType())->getPointeeType();
656         ClassTy.print(OS, PrintingPolicy(LangOptions()));
657       }
658     }
659     OS << ' ' << OMD->getSelector().getAsString() << ']';
660 
661   }
662 
663   return OS.str();
664 }
665 
666 AnalysisConsumer::AnalysisMode
getModeForDecl(Decl * D,AnalysisMode Mode)667 AnalysisConsumer::getModeForDecl(Decl *D, AnalysisMode Mode) {
668   if (!Opts->AnalyzeSpecificFunction.empty() &&
669       getFunctionName(D) != Opts->AnalyzeSpecificFunction)
670     return AM_None;
671 
672   // Unless -analyze-all is specified, treat decls differently depending on
673   // where they came from:
674   // - Main source file: run both path-sensitive and non-path-sensitive checks.
675   // - Header files: run non-path-sensitive checks only.
676   // - System headers: don't run any checks.
677   SourceManager &SM = Ctx->getSourceManager();
678   const Stmt *Body = D->getBody();
679   SourceLocation SL = Body ? Body->getBeginLoc() : D->getLocation();
680   SL = SM.getExpansionLoc(SL);
681 
682   if (!Opts->AnalyzeAll && !Mgr->isInCodeFile(SL)) {
683     if (SL.isInvalid() || SM.isInSystemHeader(SL))
684       return AM_None;
685     return Mode & ~AM_Path;
686   }
687 
688   return Mode;
689 }
690 
HandleCode(Decl * D,AnalysisMode Mode,ExprEngine::InliningModes IMode,SetOfConstDecls * VisitedCallees)691 void AnalysisConsumer::HandleCode(Decl *D, AnalysisMode Mode,
692                                   ExprEngine::InliningModes IMode,
693                                   SetOfConstDecls *VisitedCallees) {
694   if (!D->hasBody())
695     return;
696   Mode = getModeForDecl(D, Mode);
697   if (Mode == AM_None)
698     return;
699 
700   // Clear the AnalysisManager of old AnalysisDeclContexts.
701   Mgr->ClearContexts();
702   // Ignore autosynthesized code.
703   if (Mgr->getAnalysisDeclContext(D)->isBodyAutosynthesized())
704     return;
705 
706   DisplayFunction(D, Mode, IMode);
707   CFG *DeclCFG = Mgr->getCFG(D);
708   if (DeclCFG)
709     MaxCFGSize.updateMax(DeclCFG->size());
710 
711   BugReporter BR(*Mgr);
712 
713   if (Mode & AM_Syntax)
714     checkerMgr->runCheckersOnASTBody(D, *Mgr, BR);
715   if ((Mode & AM_Path) && checkerMgr->hasPathSensitiveCheckers()) {
716     RunPathSensitiveChecks(D, IMode, VisitedCallees);
717     if (IMode != ExprEngine::Inline_Minimal)
718       NumFunctionsAnalyzed++;
719   }
720 }
721 
722 //===----------------------------------------------------------------------===//
723 // Path-sensitive checking.
724 //===----------------------------------------------------------------------===//
725 
RunPathSensitiveChecks(Decl * D,ExprEngine::InliningModes IMode,SetOfConstDecls * VisitedCallees)726 void AnalysisConsumer::RunPathSensitiveChecks(Decl *D,
727                                               ExprEngine::InliningModes IMode,
728                                               SetOfConstDecls *VisitedCallees) {
729   // Construct the analysis engine.  First check if the CFG is valid.
730   // FIXME: Inter-procedural analysis will need to handle invalid CFGs.
731   if (!Mgr->getCFG(D))
732     return;
733 
734   // See if the LiveVariables analysis scales.
735   if (!Mgr->getAnalysisDeclContext(D)->getAnalysis<RelaxedLiveVariables>())
736     return;
737 
738   ExprEngine Eng(CTU, *Mgr, VisitedCallees, &FunctionSummaries, IMode);
739 
740   // Execute the worklist algorithm.
741   Eng.ExecuteWorkList(Mgr->getAnalysisDeclContextManager().getStackFrame(D),
742                       Mgr->options.MaxNodesPerTopLevelFunction);
743 
744   if (!Mgr->options.DumpExplodedGraphTo.empty())
745     Eng.DumpGraph(Mgr->options.TrimGraph, Mgr->options.DumpExplodedGraphTo);
746 
747   // Visualize the exploded graph.
748   if (Mgr->options.visualizeExplodedGraphWithGraphViz)
749     Eng.ViewGraph(Mgr->options.TrimGraph);
750 
751   // Display warnings.
752   Eng.getBugReporter().FlushReports();
753 }
754 
755 //===----------------------------------------------------------------------===//
756 // AnalysisConsumer creation.
757 //===----------------------------------------------------------------------===//
758 
759 std::unique_ptr<AnalysisASTConsumer>
CreateAnalysisConsumer(CompilerInstance & CI)760 ento::CreateAnalysisConsumer(CompilerInstance &CI) {
761   // Disable the effects of '-Werror' when using the AnalysisConsumer.
762   CI.getPreprocessor().getDiagnostics().setWarningsAsErrors(false);
763 
764   AnalyzerOptionsRef analyzerOpts = CI.getAnalyzerOpts();
765   bool hasModelPath = analyzerOpts->Config.count("model-path") > 0;
766 
767   return llvm::make_unique<AnalysisConsumer>(
768       CI, CI.getFrontendOpts().OutputFile, analyzerOpts,
769       CI.getFrontendOpts().Plugins,
770       hasModelPath ? new ModelInjector(CI) : nullptr);
771 }
772