xref: /freebsd/contrib/llvm-project/clang/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp (revision 700637cbb5e582861067a11aaca4d053546871d2)
1 //===--- AnalysisConsumer.cpp - ASTConsumer for running Analyses ----------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // "Meta" ASTConsumer for running different source analyses.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/StaticAnalyzer/Frontend/AnalysisConsumer.h"
14 #include "ModelInjector.h"
15 #include "clang/AST/Decl.h"
16 #include "clang/AST/DeclCXX.h"
17 #include "clang/AST/DeclObjC.h"
18 #include "clang/AST/DynamicRecursiveASTVisitor.h"
19 #include "clang/Analysis/Analyses/LiveVariables.h"
20 #include "clang/Analysis/CFG.h"
21 #include "clang/Analysis/CallGraph.h"
22 #include "clang/Analysis/CodeInjector.h"
23 #include "clang/Analysis/MacroExpansionContext.h"
24 #include "clang/Analysis/PathDiagnostic.h"
25 #include "clang/Basic/SourceManager.h"
26 #include "clang/CrossTU/CrossTranslationUnit.h"
27 #include "clang/Frontend/CompilerInstance.h"
28 #include "clang/Lex/Preprocessor.h"
29 #include "clang/Rewrite/Core/Rewriter.h"
30 #include "clang/StaticAnalyzer/Core/AnalyzerOptions.h"
31 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.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/EntryPointStats.h"
36 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
37 #include "llvm/ADT/PostOrderIterator.h"
38 #include "llvm/ADT/ScopeExit.h"
39 #include "llvm/Support/TimeProfiler.h"
40 #include "llvm/Support/Timer.h"
41 #include "llvm/Support/raw_ostream.h"
42 #include <memory>
43 #include <utility>
44 
45 using namespace clang;
46 using namespace ento;
47 
48 #define DEBUG_TYPE "AnalysisConsumer"
49 
50 STAT_COUNTER(NumFunctionTopLevel, "The # of functions at top level.");
51 ALWAYS_ENABLED_STATISTIC(NumFunctionsAnalyzed,
52                          "The # of functions and blocks analyzed (as top level "
53                          "with inlining turned on).");
54 ALWAYS_ENABLED_STATISTIC(NumBlocksInAnalyzedFunctions,
55                          "The # of basic blocks in the analyzed functions.");
56 ALWAYS_ENABLED_STATISTIC(
57     NumVisitedBlocksInAnalyzedFunctions,
58     "The # of visited basic blocks in the analyzed functions.");
59 ALWAYS_ENABLED_STATISTIC(PercentReachableBlocks,
60                          "The % of reachable basic blocks.");
61 STAT_MAX(MaxCFGSize, "The maximum number of basic blocks in a function.");
62 //===----------------------------------------------------------------------===//
63 // AnalysisConsumer declaration.
64 //===----------------------------------------------------------------------===//
65 
66 namespace {
67 
68 class AnalysisConsumer : public AnalysisASTConsumer,
69                          public DynamicRecursiveASTVisitor {
70   enum {
71     AM_None = 0,
72     AM_Syntax = 0x1,
73     AM_Path = 0x2
74   };
75   typedef unsigned AnalysisMode;
76 
77   /// Mode of the analyzes while recursively visiting Decls.
78   AnalysisMode RecVisitorMode;
79   /// Bug Reporter to use while recursively visiting Decls.
80   BugReporter *RecVisitorBR;
81 
82   std::vector<std::function<void(CheckerRegistry &)>> CheckerRegistrationFns;
83 
84 public:
85   ASTContext *Ctx;
86   Preprocessor &PP;
87   const std::string OutDir;
88   AnalyzerOptions &Opts;
89   ArrayRef<std::string> Plugins;
90   std::unique_ptr<CodeInjector> Injector;
91   cross_tu::CrossTranslationUnitContext CTU;
92 
93   /// Stores the declarations from the local translation unit.
94   /// Note, we pre-compute the local declarations at parse time as an
95   /// optimization to make sure we do not deserialize everything from disk.
96   /// The local declaration to all declarations ratio might be very small when
97   /// working with a PCH file.
98   SetOfDecls LocalTUDecls;
99 
100   MacroExpansionContext MacroExpansions;
101 
102   // Set of PathDiagnosticConsumers.  Owned by AnalysisManager.
103   PathDiagnosticConsumers PathConsumers;
104 
105   StoreManagerCreator CreateStoreMgr;
106   ConstraintManagerCreator CreateConstraintMgr;
107 
108   std::unique_ptr<CheckerManager> checkerMgr;
109   std::unique_ptr<AnalysisManager> Mgr;
110 
111   /// Time the analyzes time of each translation unit.
112   std::unique_ptr<llvm::TimerGroup> AnalyzerTimers;
113   std::unique_ptr<llvm::Timer> SyntaxCheckTimer;
114   std::unique_ptr<llvm::Timer> ExprEngineTimer;
115   std::unique_ptr<llvm::Timer> BugReporterTimer;
116 
117   /// The information about analyzed functions shared throughout the
118   /// translation unit.
119   FunctionSummariesTy FunctionSummaries;
120 
AnalysisConsumer(CompilerInstance & CI,const std::string & outdir,AnalyzerOptions & opts,ArrayRef<std::string> plugins,std::unique_ptr<CodeInjector> injector)121   AnalysisConsumer(CompilerInstance &CI, const std::string &outdir,
122                    AnalyzerOptions &opts, ArrayRef<std::string> plugins,
123                    std::unique_ptr<CodeInjector> injector)
124       : RecVisitorMode(0), RecVisitorBR(nullptr), Ctx(nullptr),
125         PP(CI.getPreprocessor()), OutDir(outdir), Opts(opts), Plugins(plugins),
126         Injector(std::move(injector)), CTU(CI),
127         MacroExpansions(CI.getLangOpts()) {
128     EntryPointStat::lockRegistry();
129     DigestAnalyzerOptions();
130 
131     if (Opts.AnalyzerDisplayProgress || Opts.PrintStats ||
132         Opts.ShouldSerializeStats) {
133       AnalyzerTimers = std::make_unique<llvm::TimerGroup>(
134           "analyzer", "Analyzer timers");
135       SyntaxCheckTimer = std::make_unique<llvm::Timer>(
136           "syntaxchecks", "Syntax-based analysis time", *AnalyzerTimers);
137       ExprEngineTimer = std::make_unique<llvm::Timer>(
138           "exprengine", "Path exploration time", *AnalyzerTimers);
139       BugReporterTimer = std::make_unique<llvm::Timer>(
140           "bugreporter", "Path-sensitive report post-processing time",
141           *AnalyzerTimers);
142     }
143 
144     if (Opts.PrintStats || Opts.ShouldSerializeStats) {
145       llvm::EnableStatistics(/* DoPrintOnExit= */ false);
146     }
147 
148     if (Opts.ShouldDisplayMacroExpansions)
149       MacroExpansions.registerForPreprocessor(PP);
150 
151     // Visitor options.
152     ShouldWalkTypesOfTypeLocs = false;
153   }
154 
~AnalysisConsumer()155   ~AnalysisConsumer() override {
156     if (Opts.PrintStats) {
157       llvm::PrintStatistics();
158     }
159   }
160 
DigestAnalyzerOptions()161   void DigestAnalyzerOptions() {
162     switch (Opts.AnalysisDiagOpt) {
163     case PD_NONE:
164       break;
165 #define ANALYSIS_DIAGNOSTICS(NAME, CMDFLAG, DESC, CREATEFN)                    \
166   case PD_##NAME:                                                              \
167     CREATEFN(Opts.getDiagOpts(), PathConsumers, OutDir, PP, CTU,              \
168              MacroExpansions);                                                 \
169     break;
170 #include "clang/StaticAnalyzer/Core/Analyses.def"
171     default:
172       llvm_unreachable("Unknown analyzer output type!");
173     }
174 
175     // Create the analyzer component creators.
176     CreateStoreMgr = &CreateRegionStoreManager;
177 
178     switch (Opts.AnalysisConstraintsOpt) {
179     default:
180       llvm_unreachable("Unknown constraint manager.");
181 #define ANALYSIS_CONSTRAINTS(NAME, CMDFLAG, DESC, CREATEFN)     \
182       case NAME##Model: CreateConstraintMgr = CREATEFN; break;
183 #include "clang/StaticAnalyzer/Core/Analyses.def"
184     }
185   }
186 
DisplayTime(llvm::TimeRecord & Time)187   void DisplayTime(llvm::TimeRecord &Time) {
188     if (!Opts.AnalyzerDisplayProgress) {
189       return;
190     }
191     llvm::errs() << " : " << llvm::format("%1.1f", Time.getWallTime() * 1000)
192                  << " ms\n";
193   }
194 
DisplayFunction(const Decl * D,AnalysisMode Mode,ExprEngine::InliningModes IMode)195   void DisplayFunction(const Decl *D, AnalysisMode Mode,
196                        ExprEngine::InliningModes IMode) {
197     if (!Opts.AnalyzerDisplayProgress)
198       return;
199 
200     SourceManager &SM = Mgr->getASTContext().getSourceManager();
201     PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
202     if (Loc.isValid()) {
203       llvm::errs() << "ANALYZE";
204 
205       if (Mode == AM_Syntax)
206         llvm::errs() << " (Syntax)";
207       else if (Mode == AM_Path) {
208         llvm::errs() << " (Path, ";
209         switch (IMode) {
210         case ExprEngine::Inline_Minimal:
211           llvm::errs() << " Inline_Minimal";
212           break;
213         case ExprEngine::Inline_Regular:
214           llvm::errs() << " Inline_Regular";
215           break;
216         }
217         llvm::errs() << ")";
218       } else
219         assert(Mode == (AM_Syntax | AM_Path) && "Unexpected mode!");
220 
221       llvm::errs() << ": " << Loc.getFilename() << ' '
222                    << AnalysisDeclContext::getFunctionName(D);
223     }
224   }
225 
226   /// Store the top level decls in the set to be processed later on.
227   /// (Doing this pre-processing avoids deserialization of data from PCH.)
228   bool HandleTopLevelDecl(DeclGroupRef D) override;
229   void HandleTopLevelDeclInObjCContainer(DeclGroupRef D) override;
230 
231   void HandleTranslationUnit(ASTContext &C) override;
232 
233   /// Determine which inlining mode should be used when this function is
234   /// analyzed. This allows to redefine the default inlining policies when
235   /// analyzing a given function.
236   ExprEngine::InliningModes
237     getInliningModeForFunction(const Decl *D, const SetOfConstDecls &Visited);
238 
239   /// Build the call graph for all the top level decls of this TU and
240   /// use it to define the order in which the functions should be visited.
241   void HandleDeclsCallGraph(const unsigned LocalTUDeclsSize);
242 
243   /// Run analyzes(syntax or path sensitive) on the given function.
244   /// \param Mode - determines if we are requesting syntax only or path
245   /// sensitive only analysis.
246   /// \param VisitedCallees - The output parameter, which is populated with the
247   /// set of functions which should be considered analyzed after analyzing the
248   /// given root function.
249   void HandleCode(Decl *D, AnalysisMode Mode,
250                   ExprEngine::InliningModes IMode = ExprEngine::Inline_Minimal,
251                   SetOfConstDecls *VisitedCallees = nullptr);
252 
253   void RunPathSensitiveChecks(Decl *D,
254                               ExprEngine::InliningModes IMode,
255                               SetOfConstDecls *VisitedCallees);
256 
257   /// Handle callbacks for arbitrary Decls.
VisitDecl(Decl * D)258   bool VisitDecl(Decl *D) override {
259     AnalysisMode Mode = getModeForDecl(D, RecVisitorMode);
260     if (Mode & AM_Syntax) {
261       if (SyntaxCheckTimer)
262         SyntaxCheckTimer->startTimer();
263       checkerMgr->runCheckersOnASTDecl(D, *Mgr, *RecVisitorBR);
264       if (SyntaxCheckTimer)
265         SyntaxCheckTimer->stopTimer();
266     }
267     return true;
268   }
269 
VisitVarDecl(VarDecl * VD)270   bool VisitVarDecl(VarDecl *VD) override {
271     if (!Opts.IsNaiveCTUEnabled)
272       return true;
273 
274     if (VD->hasExternalStorage() || VD->isStaticDataMember()) {
275       if (!cross_tu::shouldImport(VD, *Ctx))
276         return true;
277     } else {
278       // Cannot be initialized in another TU.
279       return true;
280     }
281 
282     if (VD->getAnyInitializer())
283       return true;
284 
285     llvm::Expected<const VarDecl *> CTUDeclOrError =
286       CTU.getCrossTUDefinition(VD, Opts.CTUDir, Opts.CTUIndexName,
287                                Opts.DisplayCTUProgress);
288 
289     if (!CTUDeclOrError) {
290       handleAllErrors(CTUDeclOrError.takeError(),
291                       [&](const cross_tu::IndexError &IE) {
292                         CTU.emitCrossTUDiagnostics(IE);
293                       });
294     }
295 
296     return true;
297   }
298 
VisitFunctionDecl(FunctionDecl * FD)299   bool VisitFunctionDecl(FunctionDecl *FD) override {
300     IdentifierInfo *II = FD->getIdentifier();
301     if (II && II->getName().starts_with("__inline"))
302       return true;
303 
304     // We skip function template definitions, as their semantics is
305     // only determined when they are instantiated.
306     if (FD->isThisDeclarationADefinition() &&
307         !FD->isDependentContext()) {
308       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
309       HandleCode(FD, RecVisitorMode);
310     }
311     return true;
312   }
313 
VisitObjCMethodDecl(ObjCMethodDecl * MD)314   bool VisitObjCMethodDecl(ObjCMethodDecl *MD) override {
315     if (MD->isThisDeclarationADefinition()) {
316       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
317       HandleCode(MD, RecVisitorMode);
318     }
319     return true;
320   }
321 
VisitBlockDecl(BlockDecl * BD)322   bool VisitBlockDecl(BlockDecl *BD) override {
323     if (BD->hasBody()) {
324       assert(RecVisitorMode == AM_Syntax || Mgr->shouldInlineCall() == false);
325       // Since we skip function template definitions, we should skip blocks
326       // declared in those functions as well.
327       if (!BD->isDependentContext()) {
328         HandleCode(BD, RecVisitorMode);
329       }
330     }
331     return true;
332   }
333 
AddDiagnosticConsumer(std::unique_ptr<PathDiagnosticConsumer> Consumer)334   void AddDiagnosticConsumer(
335       std::unique_ptr<PathDiagnosticConsumer> Consumer) override {
336     PathConsumers.push_back(std::move(Consumer));
337   }
338 
AddCheckerRegistrationFn(std::function<void (CheckerRegistry &)> Fn)339   void AddCheckerRegistrationFn(std::function<void(CheckerRegistry&)> Fn) override {
340     CheckerRegistrationFns.push_back(std::move(Fn));
341   }
342 
343 private:
344   void storeTopLevelDecls(DeclGroupRef DG);
345 
346   /// Check if we should skip (not analyze) the given function.
347   AnalysisMode getModeForDecl(Decl *D, AnalysisMode Mode);
348   void runAnalysisOnTranslationUnit(ASTContext &C);
349 
350   /// Print \p S to stderr if \c Opts.AnalyzerDisplayProgress is set.
351   void reportAnalyzerProgress(StringRef S);
352 };
353 
timeTraceScopeDeclName(StringRef FunName,const Decl * D)354 std::string timeTraceScopeDeclName(StringRef FunName, const Decl *D) {
355   if (llvm::timeTraceProfilerEnabled()) {
356     if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
357       return (FunName + " " + ND->getQualifiedNameAsString()).str();
358     return (FunName + " <anonymous> ").str();
359   }
360   return "";
361 }
362 
timeTraceScopeDeclMetadata(const Decl * D)363 llvm::TimeTraceMetadata timeTraceScopeDeclMetadata(const Decl *D) {
364   // If time-trace profiler is not enabled, this function is never called.
365   assert(llvm::timeTraceProfilerEnabled());
366   if (const auto &Loc = D->getBeginLoc(); Loc.isValid()) {
367     const auto &SM = D->getASTContext().getSourceManager();
368     std::string DeclName = AnalysisDeclContext::getFunctionName(D);
369     return llvm::TimeTraceMetadata{
370         std::move(DeclName), SM.getFilename(Loc).str(),
371         static_cast<int>(SM.getExpansionLineNumber(Loc))};
372   }
373   return llvm::TimeTraceMetadata{"", ""};
374 }
375 
flushReports(llvm::Timer * BugReporterTimer,BugReporter & BR)376 void flushReports(llvm::Timer *BugReporterTimer, BugReporter &BR) {
377   llvm::TimeTraceScope TCS{"Flushing reports"};
378   // Display warnings.
379   if (BugReporterTimer)
380     BugReporterTimer->startTimer();
381   BR.FlushReports();
382   if (BugReporterTimer)
383     BugReporterTimer->stopTimer();
384 }
385 } // namespace
386 
387 //===----------------------------------------------------------------------===//
388 // AnalysisConsumer implementation.
389 //===----------------------------------------------------------------------===//
HandleTopLevelDecl(DeclGroupRef DG)390 bool AnalysisConsumer::HandleTopLevelDecl(DeclGroupRef DG) {
391   storeTopLevelDecls(DG);
392   return true;
393 }
394 
HandleTopLevelDeclInObjCContainer(DeclGroupRef DG)395 void AnalysisConsumer::HandleTopLevelDeclInObjCContainer(DeclGroupRef DG) {
396   storeTopLevelDecls(DG);
397 }
398 
storeTopLevelDecls(DeclGroupRef DG)399 void AnalysisConsumer::storeTopLevelDecls(DeclGroupRef DG) {
400   for (auto &I : DG) {
401 
402     // Skip ObjCMethodDecl, wait for the objc container to avoid
403     // analyzing twice.
404     if (isa<ObjCMethodDecl>(I))
405       continue;
406 
407     LocalTUDecls.push_back(I);
408   }
409 }
410 
shouldSkipFunction(const Decl * D,const SetOfConstDecls & Visited,const SetOfConstDecls & VisitedAsTopLevel)411 static bool shouldSkipFunction(const Decl *D,
412                                const SetOfConstDecls &Visited,
413                                const SetOfConstDecls &VisitedAsTopLevel) {
414   if (VisitedAsTopLevel.count(D))
415     return true;
416 
417   // Skip analysis of inheriting constructors as top-level functions. These
418   // constructors don't even have a body written down in the code, so even if
419   // we find a bug, we won't be able to display it.
420   if (const auto *CD = dyn_cast<CXXConstructorDecl>(D))
421     if (CD->isInheritingConstructor())
422       return true;
423 
424   // We want to re-analyse the functions as top level in the following cases:
425   // - The 'init' methods should be reanalyzed because
426   //   ObjCNonNilReturnValueChecker assumes that '[super init]' never returns
427   //   'nil' and unless we analyze the 'init' functions as top level, we will
428   //   not catch errors within defensive code.
429   // - We want to reanalyze all ObjC methods as top level to report Retain
430   //   Count naming convention errors more aggressively.
431   if (isa<ObjCMethodDecl>(D))
432     return false;
433   // We also want to reanalyze all C++ copy and move assignment operators to
434   // separately check the two cases where 'this' aliases with the parameter and
435   // where it may not. (cplusplus.SelfAssignmentChecker)
436   if (const auto *MD = dyn_cast<CXXMethodDecl>(D)) {
437     if (MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())
438       return false;
439   }
440 
441   // Otherwise, if we visited the function before, do not reanalyze it.
442   return Visited.count(D);
443 }
444 
445 ExprEngine::InliningModes
getInliningModeForFunction(const Decl * D,const SetOfConstDecls & Visited)446 AnalysisConsumer::getInliningModeForFunction(const Decl *D,
447                                              const SetOfConstDecls &Visited) {
448   // We want to reanalyze all ObjC methods as top level to report Retain
449   // Count naming convention errors more aggressively. But we should tune down
450   // inlining when reanalyzing an already inlined function.
451   if (Visited.count(D) && isa<ObjCMethodDecl>(D)) {
452     const ObjCMethodDecl *ObjCM = cast<ObjCMethodDecl>(D);
453     if (ObjCM->getMethodFamily() != OMF_init)
454       return ExprEngine::Inline_Minimal;
455   }
456 
457   return ExprEngine::Inline_Regular;
458 }
459 
HandleDeclsCallGraph(const unsigned LocalTUDeclsSize)460 void AnalysisConsumer::HandleDeclsCallGraph(const unsigned LocalTUDeclsSize) {
461   // Build the Call Graph by adding all the top level declarations to the graph.
462   // Note: CallGraph can trigger deserialization of more items from a pch
463   // (though HandleInterestingDecl); triggering additions to LocalTUDecls.
464   // We rely on random access to add the initially processed Decls to CG.
465   CallGraph CG;
466   for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) {
467     CG.addToCallGraph(LocalTUDecls[i]);
468   }
469 
470   // Walk over all of the call graph nodes in topological order, so that we
471   // analyze parents before the children. Skip the functions inlined into
472   // the previously processed functions. Use external Visited set to identify
473   // inlined functions. The topological order allows the "do not reanalyze
474   // previously inlined function" performance heuristic to be triggered more
475   // often.
476   SetOfConstDecls Visited;
477   SetOfConstDecls VisitedAsTopLevel;
478   llvm::ReversePostOrderTraversal<clang::CallGraph*> RPOT(&CG);
479   for (auto &N : RPOT) {
480     NumFunctionTopLevel++;
481 
482     Decl *D = N->getDecl();
483 
484     // Skip the abstract root node.
485     if (!D)
486       continue;
487 
488     // Skip the functions which have been processed already or previously
489     // inlined.
490     if (shouldSkipFunction(D, Visited, VisitedAsTopLevel))
491       continue;
492 
493     // The CallGraph might have declarations as callees. However, during CTU
494     // the declaration might form a declaration chain with the newly imported
495     // definition from another TU. In this case we don't want to analyze the
496     // function definition as toplevel.
497     if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
498       // Calling 'hasBody' replaces 'FD' in place with the FunctionDecl
499       // that has the body.
500       FD->hasBody(FD);
501       if (CTU.isImportedAsNew(FD))
502         continue;
503     }
504 
505     // Analyze the function.
506     SetOfConstDecls VisitedCallees;
507 
508     HandleCode(D, AM_Path, getInliningModeForFunction(D, Visited),
509                (Mgr->options.InliningMode == All ? nullptr : &VisitedCallees));
510 
511     // Add the visited callees to the global visited set.
512     for (const Decl *Callee : VisitedCallees)
513       // Decls from CallGraph are already canonical. But Decls coming from
514       // CallExprs may be not. We should canonicalize them manually.
515       Visited.insert(isa<ObjCMethodDecl>(Callee) ? Callee
516                                                  : Callee->getCanonicalDecl());
517     VisitedAsTopLevel.insert(D);
518   }
519 }
520 
fileContainsString(StringRef Substring,ASTContext & C)521 static bool fileContainsString(StringRef Substring, ASTContext &C) {
522   const SourceManager &SM = C.getSourceManager();
523   FileID FID = SM.getMainFileID();
524   StringRef Buffer = SM.getBufferOrFake(FID).getBuffer();
525   return Buffer.contains(Substring);
526 }
527 
reportAnalyzerFunctionMisuse(const AnalyzerOptions & Opts,const ASTContext & Ctx)528 static void reportAnalyzerFunctionMisuse(const AnalyzerOptions &Opts,
529                                          const ASTContext &Ctx) {
530   llvm::errs() << "Every top-level function was skipped.\n";
531 
532   if (!Opts.AnalyzerDisplayProgress)
533     llvm::errs() << "Pass the -analyzer-display-progress for tracking which "
534                     "functions are analyzed.\n";
535 
536   bool HasBrackets =
537       Opts.AnalyzeSpecificFunction.find("(") != std::string::npos;
538 
539   if (Ctx.getLangOpts().CPlusPlus && !HasBrackets) {
540     llvm::errs()
541         << "For analyzing C++ code you need to pass the function parameter "
542            "list: -analyze-function=\"foobar(int, _Bool)\"\n";
543   } else if (!Ctx.getLangOpts().CPlusPlus && HasBrackets) {
544     llvm::errs() << "For analyzing C code you shouldn't pass the function "
545                     "parameter list, only the name of the function: "
546                     "-analyze-function=foobar\n";
547   }
548 }
549 
runAnalysisOnTranslationUnit(ASTContext & C)550 void AnalysisConsumer::runAnalysisOnTranslationUnit(ASTContext &C) {
551   BugReporter BR(*Mgr);
552   const TranslationUnitDecl *TU = C.getTranslationUnitDecl();
553   BR.setAnalysisEntryPoint(TU);
554   if (SyntaxCheckTimer)
555     SyntaxCheckTimer->startTimer();
556   checkerMgr->runCheckersOnASTDecl(TU, *Mgr, BR);
557   if (SyntaxCheckTimer)
558     SyntaxCheckTimer->stopTimer();
559 
560   // Run the AST-only checks using the order in which functions are defined.
561   // If inlining is not turned on, use the simplest function order for path
562   // sensitive analyzes as well.
563   RecVisitorMode = AM_Syntax;
564   if (!Mgr->shouldInlineCall())
565     RecVisitorMode |= AM_Path;
566   RecVisitorBR = &BR;
567 
568   // Process all the top level declarations.
569   //
570   // Note: TraverseDecl may modify LocalTUDecls, but only by appending more
571   // entries.  Thus we don't use an iterator, but rely on LocalTUDecls
572   // random access.  By doing so, we automatically compensate for iterators
573   // possibly being invalidated, although this is a bit slower.
574   const unsigned LocalTUDeclsSize = LocalTUDecls.size();
575   for (unsigned i = 0 ; i < LocalTUDeclsSize ; ++i) {
576     TraverseDecl(LocalTUDecls[i]);
577   }
578 
579   if (Mgr->shouldInlineCall())
580     HandleDeclsCallGraph(LocalTUDeclsSize);
581 
582   // After all decls handled, run checkers on the entire TranslationUnit.
583   checkerMgr->runCheckersOnEndOfTranslationUnit(TU, *Mgr, BR);
584 
585   BR.FlushReports();
586   RecVisitorBR = nullptr;
587 
588   // If the user wanted to analyze a specific function and the number of basic
589   // blocks analyzed is zero, than the user might not specified the function
590   // name correctly.
591   // FIXME: The user might have analyzed the requested function in Syntax mode,
592   // but we are unaware of that.
593   if (!Opts.AnalyzeSpecificFunction.empty() && NumFunctionsAnalyzed == 0)
594     reportAnalyzerFunctionMisuse(Opts, *Ctx);
595 }
596 
reportAnalyzerProgress(StringRef S)597 void AnalysisConsumer::reportAnalyzerProgress(StringRef S) {
598   if (Opts.AnalyzerDisplayProgress)
599     llvm::errs() << S;
600 }
601 
HandleTranslationUnit(ASTContext & C)602 void AnalysisConsumer::HandleTranslationUnit(ASTContext &C) {
603   // Don't run the actions if an error has occurred with parsing the file.
604   DiagnosticsEngine &Diags = PP.getDiagnostics();
605   if (Diags.hasErrorOccurred() || Diags.hasFatalErrorOccurred())
606     return;
607 
608   Ctx = &C;
609   checkerMgr = std::make_unique<CheckerManager>(*Ctx, Opts, PP, Plugins,
610                                                 CheckerRegistrationFns);
611 
612   Mgr = std::make_unique<AnalysisManager>(
613       *Ctx, PP, std::move(PathConsumers), CreateStoreMgr, CreateConstraintMgr,
614       checkerMgr.get(), Opts, std::move(Injector));
615 
616   // Explicitly destroy the PathDiagnosticConsumer.  This will flush its output.
617   // FIXME: This should be replaced with something that doesn't rely on
618   // side-effects in PathDiagnosticConsumer's destructor. This is required when
619   // used with option -disable-free.
620   const auto DiagFlusherScopeExit =
621       llvm::make_scope_exit([this] { Mgr.reset(); });
622 
623   if (Opts.ShouldIgnoreBisonGeneratedFiles &&
624       fileContainsString("/* A Bison parser, made by", C)) {
625     reportAnalyzerProgress("Skipping bison-generated file\n");
626     return;
627   }
628 
629   if (Opts.ShouldIgnoreFlexGeneratedFiles &&
630       fileContainsString("/* A lexical scanner generated by flex", C)) {
631     reportAnalyzerProgress("Skipping flex-generated file\n");
632     return;
633   }
634 
635   // Don't analyze if the user explicitly asked for no checks to be performed
636   // on this file.
637   if (Opts.DisableAllCheckers) {
638     reportAnalyzerProgress("All checks are disabled using a supplied option\n");
639     return;
640   }
641 
642   // Otherwise, just run the analysis.
643   runAnalysisOnTranslationUnit(C);
644 
645   // Count how many basic blocks we have not covered.
646   NumBlocksInAnalyzedFunctions = FunctionSummaries.getTotalNumBasicBlocks();
647   NumVisitedBlocksInAnalyzedFunctions =
648       FunctionSummaries.getTotalNumVisitedBasicBlocks();
649   if (NumBlocksInAnalyzedFunctions > 0)
650     PercentReachableBlocks =
651         (FunctionSummaries.getTotalNumVisitedBasicBlocks() * 100) /
652         NumBlocksInAnalyzedFunctions;
653 
654   if (!Opts.DumpEntryPointStatsToCSV.empty()) {
655     EntryPointStat::dumpStatsAsCSV(Opts.DumpEntryPointStatsToCSV);
656   }
657 }
658 
659 AnalysisConsumer::AnalysisMode
getModeForDecl(Decl * D,AnalysisMode Mode)660 AnalysisConsumer::getModeForDecl(Decl *D, AnalysisMode Mode) {
661   if (!Opts.AnalyzeSpecificFunction.empty() &&
662       AnalysisDeclContext::getFunctionName(D) != Opts.AnalyzeSpecificFunction)
663     return AM_None;
664 
665   // Unless -analyze-all is specified, treat decls differently depending on
666   // where they came from:
667   // - Main source file: run both path-sensitive and non-path-sensitive checks.
668   // - Header files: run non-path-sensitive checks only.
669   // - System headers: don't run any checks.
670   if (Opts.AnalyzeAll)
671     return Mode;
672 
673   const SourceManager &SM = Ctx->getSourceManager();
674 
675   const SourceLocation Loc = [&SM](Decl *D) -> SourceLocation {
676     const Stmt *Body = D->getBody();
677     SourceLocation SL = Body ? Body->getBeginLoc() : D->getLocation();
678     return SM.getExpansionLoc(SL);
679   }(D);
680 
681   // Ignore system headers.
682   if (Loc.isInvalid() || SM.isInSystemHeader(Loc))
683     return AM_None;
684 
685   // Disable path sensitive analysis in user-headers.
686   if (!Mgr->isInCodeFile(Loc))
687     return Mode & ~AM_Path;
688 
689   return Mode;
690 }
691 
692 static UnsignedEPStat PathRunningTime("PathRunningTime");
693 
HandleCode(Decl * D,AnalysisMode Mode,ExprEngine::InliningModes IMode,SetOfConstDecls * VisitedCallees)694 void AnalysisConsumer::HandleCode(Decl *D, AnalysisMode Mode,
695                                   ExprEngine::InliningModes IMode,
696                                   SetOfConstDecls *VisitedCallees) {
697   llvm::TimeTraceScope TCS(timeTraceScopeDeclName("HandleCode", D),
698                            [D]() { return timeTraceScopeDeclMetadata(D); });
699   if (!D->hasBody())
700     return;
701   Mode = getModeForDecl(D, Mode);
702   if (Mode == AM_None)
703     return;
704 
705   // Clear the AnalysisManager of old AnalysisDeclContexts.
706   Mgr->ClearContexts();
707   // Ignore autosynthesized code.
708   if (Mgr->getAnalysisDeclContext(D)->isBodyAutosynthesized())
709     return;
710 
711   CFG *DeclCFG = Mgr->getCFG(D);
712   if (DeclCFG)
713     MaxCFGSize.updateMax(DeclCFG->size());
714 
715   DisplayFunction(D, Mode, IMode);
716   BugReporter BR(*Mgr);
717   BR.setAnalysisEntryPoint(D);
718 
719   if (Mode & AM_Syntax) {
720     llvm::TimeRecord CheckerStartTime;
721     if (SyntaxCheckTimer) {
722       CheckerStartTime = SyntaxCheckTimer->getTotalTime();
723       SyntaxCheckTimer->startTimer();
724     }
725     checkerMgr->runCheckersOnASTBody(D, *Mgr, BR);
726     if (SyntaxCheckTimer) {
727       SyntaxCheckTimer->stopTimer();
728       llvm::TimeRecord CheckerEndTime = SyntaxCheckTimer->getTotalTime();
729       CheckerEndTime -= CheckerStartTime;
730       DisplayTime(CheckerEndTime);
731     }
732   }
733 
734   BR.FlushReports();
735 
736   if ((Mode & AM_Path) && checkerMgr->hasPathSensitiveCheckers()) {
737     RunPathSensitiveChecks(D, IMode, VisitedCallees);
738     EntryPointStat::takeSnapshot(D);
739     if (IMode != ExprEngine::Inline_Minimal)
740       NumFunctionsAnalyzed++;
741   }
742 }
743 
744 //===----------------------------------------------------------------------===//
745 // Path-sensitive checking.
746 //===----------------------------------------------------------------------===//
747 
RunPathSensitiveChecks(Decl * D,ExprEngine::InliningModes IMode,SetOfConstDecls * VisitedCallees)748 void AnalysisConsumer::RunPathSensitiveChecks(Decl *D,
749                                               ExprEngine::InliningModes IMode,
750                                               SetOfConstDecls *VisitedCallees) {
751   // Construct the analysis engine.  First check if the CFG is valid.
752   // FIXME: Inter-procedural analysis will need to handle invalid CFGs.
753   if (!Mgr->getCFG(D))
754     return;
755 
756   // See if the LiveVariables analysis scales.
757   if (!Mgr->getAnalysisDeclContext(D)->getAnalysis<RelaxedLiveVariables>())
758     return;
759 
760   ExprEngine Eng(CTU, *Mgr, VisitedCallees, &FunctionSummaries, IMode);
761 
762   // Execute the worklist algorithm.
763   llvm::TimeRecord ExprEngineStartTime;
764   if (ExprEngineTimer) {
765     ExprEngineStartTime = ExprEngineTimer->getTotalTime();
766     ExprEngineTimer->startTimer();
767   }
768   Eng.ExecuteWorkList(Mgr->getAnalysisDeclContextManager().getStackFrame(D),
769                       Mgr->options.MaxNodesPerTopLevelFunction);
770   if (ExprEngineTimer) {
771     ExprEngineTimer->stopTimer();
772     llvm::TimeRecord ExprEngineEndTime = ExprEngineTimer->getTotalTime();
773     ExprEngineEndTime -= ExprEngineStartTime;
774     DisplayTime(ExprEngineEndTime);
775   }
776 
777   if (!Mgr->options.DumpExplodedGraphTo.empty())
778     Eng.DumpGraph(Mgr->options.TrimGraph, Mgr->options.DumpExplodedGraphTo);
779 
780   // Visualize the exploded graph.
781   if (Mgr->options.visualizeExplodedGraphWithGraphViz)
782     Eng.ViewGraph(Mgr->options.TrimGraph);
783 
784   flushReports(BugReporterTimer.get(), Eng.getBugReporter());
785 }
786 
787 //===----------------------------------------------------------------------===//
788 // AnalysisConsumer creation.
789 //===----------------------------------------------------------------------===//
790 
791 std::unique_ptr<AnalysisASTConsumer>
CreateAnalysisConsumer(CompilerInstance & CI)792 ento::CreateAnalysisConsumer(CompilerInstance &CI) {
793   // Disable the effects of '-Werror' when using the AnalysisConsumer.
794   CI.getPreprocessor().getDiagnostics().setWarningsAsErrors(false);
795 
796   AnalyzerOptions &analyzerOpts = CI.getAnalyzerOpts();
797   bool hasModelPath = analyzerOpts.Config.count("model-path") > 0;
798 
799   return std::make_unique<AnalysisConsumer>(
800       CI, CI.getFrontendOpts().OutputFile, analyzerOpts,
801       CI.getFrontendOpts().Plugins,
802       hasModelPath ? std::make_unique<ModelInjector>(CI) : nullptr);
803 }
804