AnalyzerStatsChecker.cpp revision f7ccbad5d9949e7ddd1cbef43d482553b811e026 
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 "ClangSACheckers.h"
13#include "clang/StaticAnalyzer/Core/Checker.h"
14#include "clang/StaticAnalyzer/Core/CheckerManager.h"
15#include "clang/StaticAnalyzer/Core/PathSensitive/ExplodedGraph.h"
16#include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
17#include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
18
19#include "clang/AST/DeclObjC.h"
20#include "clang/Basic/SourceManager.h"
21#include "llvm/ADT/SmallPtrSet.h"
22#include "llvm/ADT/SmallString.h"
23
24using namespace clang;
25using namespace ento;
26
27namespace {
28class AnalyzerStatsChecker : public Checker<check::EndAnalysis> {
29public:
30  void checkEndAnalysis(ExplodedGraph &G, BugReporter &B,ExprEngine &Eng) const;
31};
32}
33
34void AnalyzerStatsChecker::checkEndAnalysis(ExplodedGraph &G,
35                                            BugReporter &B,
36                                            ExprEngine &Eng) const {
37  const CFG *C  = 0;
38  const Decl *D = 0;
39  const LocationContext *LC = 0;
40  const SourceManager &SM = B.getSourceManager();
41  llvm::SmallPtrSet<const CFGBlock*, 256> reachable;
42
43  // Iterate over explodedgraph
44  for (ExplodedGraph::node_iterator I = G.nodes_begin();
45      I != G.nodes_end(); ++I) {
46    const ProgramPoint &P = I->getLocation();
47    // Save the LocationContext if we don't have it already
48    if (!LC)
49      LC = P.getLocationContext();
50
51    if (const BlockEntrance *BE = dyn_cast<BlockEntrance>(&P)) {
52      const CFGBlock *CB = BE->getBlock();
53      reachable.insert(CB);
54    }
55  }
56
57  // Get the CFG and the Decl of this block
58  C = LC->getCFG();
59  D = LC->getAnalysisDeclContext()->getDecl();
60
61  unsigned total = 0, unreachable = 0;
62
63  // Find CFGBlocks that were not covered by any node
64  for (CFG::const_iterator I = C->begin(); I != C->end(); ++I) {
65    const CFGBlock *CB = *I;
66    ++total;
67    // Check if the block is unreachable
68    if (!reachable.count(CB)) {
69      ++unreachable;
70    }
71  }
72
73  // We never 'reach' the entry block, so correct the unreachable count
74  unreachable--;
75
76  // Generate the warning string
77  SmallString<128> buf;
78  llvm::raw_svector_ostream output(buf);
79  PresumedLoc Loc = SM.getPresumedLoc(D->getLocation());
80  if (Loc.isValid()) {
81    output << Loc.getFilename() << " : ";
82
83    if (isa<FunctionDecl>(D) || isa<ObjCMethodDecl>(D)) {
84      const NamedDecl *ND = cast<NamedDecl>(D);
85      output << *ND;
86    }
87    else if (isa<BlockDecl>(D)) {
88      output << "block(line:" << Loc.getLine() << ":col:" << Loc.getColumn();
89    }
90  }
91
92  output << " -> Total CFGBlocks: " << total << " | Unreachable CFGBlocks: "
93      << unreachable << " | Exhausted Block: "
94      << (Eng.wasBlocksExhausted() ? "yes" : "no")
95      << " | Empty WorkList: "
96      << (Eng.hasEmptyWorkList() ? "yes" : "no");
97
98  B.EmitBasicReport("Analyzer Statistics", "Internal Statistics", output.str(),
99      PathDiagnosticLocation(D, SM));
100
101  // Emit warning for each block we bailed out on
102  typedef CoreEngine::BlocksExhausted::const_iterator ExhaustedIterator;
103  const CoreEngine &CE = Eng.getCoreEngine();
104  for (ExhaustedIterator I = CE.blocks_exhausted_begin(),
105      E = CE.blocks_exhausted_end(); I != E; ++I) {
106    const BlockEdge &BE =  I->first;
107    const CFGBlock *Exit = BE.getDst();
108    const CFGElement &CE = Exit->front();
109    if (const CFGStmt *CS = dyn_cast<CFGStmt>(&CE))
110      B.EmitBasicReport("Bailout Point", "Internal Statistics", "The analyzer "
111          "stopped analyzing at this point",
112          PathDiagnosticLocation::createBegin(CS->getStmt(), SM, LC));
113  }
114}
115
116void ento::registerAnalyzerStatsChecker(CheckerManager &mgr) {
117  mgr.registerChecker<AnalyzerStatsChecker>();
118}
119