lib/Checker/AnalyzerStatsChecker.cpp

   1 //==--AnalyzerStatsChecker.cpp - Analyzer visitation statistics --*- C++ -*-==//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 // This file reports various statistics about analyzer visitation.
  10 //===----------------------------------------------------------------------===//
  11
  12 #include "clang/GR/PathSensitive/CheckerVisitor.h"
  13 #include "clang/GR/PathSensitive/ExplodedGraph.h"
  14 #include "clang/GR/BugReporter/BugReporter.h"
  15 #include "GRExprEngineExperimentalChecks.h"
  16 #include "clang/Basic/SourceManager.h"
  17 #include "llvm/ADT/SmallPtrSet.h"
  18
  19 using namespace clang;
  20
  21 namespace {
  22 class AnalyzerStatsChecker : public CheckerVisitor<AnalyzerStatsChecker> {
  23 public:
  24   static void *getTag();
  25   void VisitEndAnalysis(ExplodedGraph &G, BugReporter &B, GRExprEngine &Eng);
  26
  27 private:
  28   llvm::SmallPtrSet<const CFGBlock*, 256> reachable;
  29 };
  30 }
  31
  32 void *AnalyzerStatsChecker::getTag() {
  33   static int x = 0;
  34   return &x;
  35 }
  36
  37 void clang::RegisterAnalyzerStatsChecker(GRExprEngine &Eng) {
  38   Eng.registerCheck(new AnalyzerStatsChecker());
  39 }
  40
  41 void AnalyzerStatsChecker::VisitEndAnalysis(ExplodedGraph &G,
  42                                             BugReporter &B,
  43                                             GRExprEngine &Eng) {
  44   const CFG *C  = 0;
  45   const Decl *D = 0;
  46   const LocationContext *LC = 0;
  47   const SourceManager &SM = B.getSourceManager();
  48
  49   // Iterate over explodedgraph
  50   for (ExplodedGraph::node_iterator I = G.nodes_begin();
  51       I != G.nodes_end(); ++I) {
  52     const ProgramPoint &P = I->getLocation();
  53     // Save the LocationContext if we don't have it already
  54     if (!LC)
  55       LC = P.getLocationContext();
  56
  57     if (const BlockEntrance *BE = dyn_cast<BlockEntrance>(&P)) {
  58       const CFGBlock *CB = BE->getBlock();
  59       reachable.insert(CB);
  60     }
  61   }
  62
  63   // Get the CFG and the Decl of this block
  64   C = LC->getCFG();
  65   D = LC->getAnalysisContext()->getDecl();
  66
  67   unsigned total = 0, unreachable = 0;
  68
  69   // Find CFGBlocks that were not covered by any node
  70   for (CFG::const_iterator I = C->begin(); I != C->end(); ++I) {
  71     const CFGBlock *CB = *I;
  72     ++total;
  73     // Check if the block is unreachable
  74     if (!reachable.count(CB)) {
  75       ++unreachable;
  76     }
  77   }
  78
  79   // We never 'reach' the entry block, so correct the unreachable count
  80   unreachable--;
  81
  82   // Generate the warning string
  83   llvm::SmallString<128> buf;
  84   llvm::raw_svector_ostream output(buf);
  85   PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
  86   if (Loc.isValid()) {
  87     output << Loc.getFilename() << " : ";
  88
  89     if (isa<FunctionDecl>(D) || isa<ObjCMethodDecl>(D)) {
  90       const NamedDecl *ND = cast<NamedDecl>(D);
  91       output << ND;
  92     }
  93     else if (isa<BlockDecl>(D)) {
  94       output << "block(line:" << Loc.getLine() << ":col:" << Loc.getColumn();
  95     }
  96   }
  97
  98   output << " -> Total CFGBlocks: " << total << " | Unreachable CFGBlocks: "
  99       << unreachable << " | Aborted Block: "
 100       << (Eng.wasBlockAborted() ? "yes" : "no")
 101       << " | Empty WorkList: "
 102       << (Eng.hasEmptyWorkList() ? "yes" : "no");
 103
 104   B.EmitBasicReport("Analyzer Statistics", "Internal Statistics", output.str(),
 105       D->getLocation());
 106
 107   // Emit warning for each block we bailed out on
 108   typedef GRCoreEngine::BlocksAborted::const_iterator AbortedIterator;
 109   const GRCoreEngine &CE = Eng.getCoreEngine();
 110   for (AbortedIterator I = CE.blocks_aborted_begin(),
 111       E = CE.blocks_aborted_end(); I != E; ++I) {
 112     const BlockEdge &BE =  I->first;
 113     const CFGBlock *Exit = BE.getDst();
 114     const CFGElement &CE = Exit->front();
 115     if (const CFGStmt *CS = dyn_cast<CFGStmt>(&CE))
 116       B.EmitBasicReport("Bailout Point", "Internal Statistics", "The analyzer "
 117           "stopped analyzing at this point", CS->getStmt()->getLocStart());
 118   }
 119 }