[analyzer] Record the basic blocks covered by the analyzes run.

Store this info inside the function summary generated for all analyzed
functions. This is useful for coverage stats and can be helpful for
analyzer state space search strategies.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@153923 91177308-0d34-0410-b5e6-96231b3b80d8

11 files changed, 174 insertions, 40 deletions

diff --git a/include/clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h b/include/clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h
index f8f7e25d8b..3cbecf7d6e 100644
--- a/include/clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h
+++ b/include/clang/StaticAnalyzer/Core/PathSensitive/AnalysisManager.h
@@ -30,33 +30,6 @@ namespace idx {
 namespace ento {
   class CheckerManager;
 
-typedef llvm::SmallPtrSet<const Decl*,24> SetOfDecls;
-
-class FunctionSummariesTy {
-  struct FunctionSummary {
-    /// True if this function has reached a max block count while inlined from
-    /// at least one call site.
-    bool MayReachMaxBlockCount;
-    FunctionSummary() : MayReachMaxBlockCount(false) {}
-  };
-
-  typedef llvm::DenseMap<const Decl*, FunctionSummary> MapTy;
-  MapTy Map;
-
-public:
-  void markReachedMaxBlockCount(const Decl* D) {
-    Map[D].MayReachMaxBlockCount = true;
-  }
-
-  bool hasReachedMaxBlockCount(const Decl* D) {
-  MapTy::const_iterator I = Map.find(D);
-    if (I != Map.end())
-      return I->second.MayReachMaxBlockCount;
-    return false;
-  }
-
-};
-
 class AnalysisManager : public BugReporterData {
   virtual void anchor();
   AnalysisDeclContextManager AnaCtxMgr;
diff --git a/include/clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h b/include/clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h
index 85d92ff5f7..d9156441db 100644
--- a/include/clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h
+++ b/include/clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h
@@ -18,6 +18,7 @@
 #include "clang/AST/Expr.h"
 #include "clang/Analysis/AnalysisContext.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/ExplodedGraph.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/FunctionSummary.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/WorkList.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/BlockCounter.h"
 #include "llvm/ADT/OwningPtr.h"
@@ -83,6 +84,10 @@ private:
   /// AnalysisConsumer. It can be null.
   SetOfDecls *AnalyzedCallees;
 
+  /// The information about functions shared by the whole translation unit.
+  /// (This data is owned by AnalysisConsumer.)
+  FunctionSummariesTy *FunctionSummaries;
+
   void generateNode(const ProgramPoint &Loc,
                     ProgramStateRef State,
                     ExplodedNode *Pred);
@@ -104,11 +109,13 @@ private:
 public:
   /// Construct a CoreEngine object to analyze the provided CFG using
   ///  a DFS exploration of the exploded graph.
-  CoreEngine(SubEngine& subengine, SetOfDecls *VisitedCallees)
+  CoreEngine(SubEngine& subengine, SetOfDecls *VisitedCallees,
+             FunctionSummariesTy *FS)
     : SubEng(subengine), G(new ExplodedGraph()),
       WList(WorkList::makeBFS()),
       BCounterFactory(G->getAllocator()),
-      AnalyzedCallees(VisitedCallees) {}
+      AnalyzedCallees(VisitedCallees),
+      FunctionSummaries(FS){}
 
   ~CoreEngine() {
     delete WList;
diff --git a/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h b/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h
index f4d2e6027b..4d1ee5436f 100644
--- a/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h
+++ b/include/clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h
@@ -90,10 +90,6 @@ class ExprEngine : public SubEngine {
   ///  destructor is called before the rest of the ExprEngine is destroyed.
   GRBugReporter BR;
 
-  /// The information about functions shared by the whole translation unit.
-  /// (This data is owned by AnalysisConsumer.)
-  FunctionSummariesTy *FunctionSummaries;
-
 public:
   ExprEngine(AnalysisManager &mgr, bool gcEnabled, SetOfDecls *VisitedCallees,
              FunctionSummariesTy *FS);
diff --git a/include/clang/StaticAnalyzer/Core/PathSensitive/FunctionSummary.h b/include/clang/StaticAnalyzer/Core/PathSensitive/FunctionSummary.h
new file mode 100644
index 0000000000..e1e15620fa
--- /dev/null
+++ b/include/clang/StaticAnalyzer/Core/PathSensitive/FunctionSummary.h
@@ -0,0 +1,96 @@
+//== FunctionSummary.h - Stores summaries of functions. ------------*- C++ -*-//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines a summary of a function gathered/used by static analyzes.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_GR_FUNCTIONSUMMARY_H
+#define LLVM_CLANG_GR_FUNCTIONSUMMARY_H
+
+#include "clang/AST/Decl.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/BitVector.h"
+
+namespace clang {
+namespace ento {
+typedef llvm::SmallPtrSet<const Decl*,24> SetOfDecls;
+
+class FunctionSummariesTy {
+  struct FunctionSummary {
+    /// True if this function has reached a max block count while inlined from
+    /// at least one call site.
+    bool MayReachMaxBlockCount;
+
+    /// Total number of blocks in the function.
+    unsigned TotalBasicBlocks;
+
+    /// Marks the IDs of the basic blocks visited during the analyzes.
+    llvm::BitVector VisitedBasicBlocks;
+
+    FunctionSummary() :
+      MayReachMaxBlockCount(false),
+      TotalBasicBlocks(0),
+      VisitedBasicBlocks(0) {}
+  };
+
+  typedef llvm::DenseMap<const Decl*, FunctionSummary*> MapTy;
+  MapTy Map;
+
+public:
+  ~FunctionSummariesTy();
+
+  MapTy::iterator findOrInsertSummary(const Decl *D) {
+    MapTy::iterator I = Map.find(D);
+    if (I != Map.end())
+      return I;
+    FunctionSummary *DS = new FunctionSummary();
+    I = Map.insert(std::pair<const Decl*, FunctionSummary*>(D, DS)).first;
+    assert(I != Map.end());
+    return I;
+  }
+
+  void markReachedMaxBlockCount(const Decl* D) {
+    MapTy::iterator I = findOrInsertSummary(D);
+    I->second->MayReachMaxBlockCount = true;
+  }
+
+  bool hasReachedMaxBlockCount(const Decl* D) {
+  MapTy::const_iterator I = Map.find(D);
+    if (I != Map.end())
+      return I->second->MayReachMaxBlockCount;
+    return false;
+  }
+
+  void markVisitedBasicBlock(unsigned ID, const Decl* D, unsigned TotalIDs) {
+    MapTy::iterator I = findOrInsertSummary(D);
+    llvm::BitVector &Blocks = I->second->VisitedBasicBlocks;
+    assert(ID < TotalIDs);
+    if (TotalIDs > Blocks.size()) {
+      Blocks.resize(TotalIDs);
+      I->second->TotalBasicBlocks = TotalIDs;
+    }
+    Blocks[ID] = true;
+  }
+
+  unsigned getNumVisitedBasicBlocks(const Decl* D) {
+    MapTy::const_iterator I = Map.find(D);
+      if (I != Map.end())
+        return I->second->VisitedBasicBlocks.count();
+    return 0;
+  }
+
+  unsigned getTotalNumBasicBlocks();
+  unsigned getTotalNumVisitedBasicBlocks();
+};
+
+}} // end clang ento namespaces
+
+#endif
diff --git a/lib/StaticAnalyzer/Core/CMakeLists.txt b/lib/StaticAnalyzer/Core/CMakeLists.txt
index 216e94a395..1ea25bd01b 100644
--- a/lib/StaticAnalyzer/Core/CMakeLists.txt
+++ b/lib/StaticAnalyzer/Core/CMakeLists.txt
@@ -22,6 +22,7 @@ add_clang_library(clangStaticAnalyzerCore
   ExprEngineCXX.cpp
   ExprEngineCallAndReturn.cpp
   ExprEngineObjC.cpp
+  FunctionSummary.cpp
   HTMLDiagnostics.cpp
   MemRegion.cpp
   ObjCMessage.cpp
diff --git a/lib/StaticAnalyzer/Core/CoreEngine.cpp b/lib/StaticAnalyzer/Core/CoreEngine.cpp
index de94f0f2dd..eb986afa3d 100644
--- a/lib/StaticAnalyzer/Core/CoreEngine.cpp
+++ b/lib/StaticAnalyzer/Core/CoreEngine.cpp
@@ -174,6 +174,11 @@ bool CoreEngine::ExecuteWorkList(const LocationContext *L, unsigned Steps,
     assert (Entry->succ_size() == 1 &&
             "Entry block must have 1 successor.");
 
+    // Mark the entry block as visited.
+    FunctionSummaries->markVisitedBasicBlock(Entry->getBlockID(),
+                                             L->getDecl(),
+                                             L->getCFG()->getNumBlockIDs());
+
     // Get the solitary successor.
     const CFGBlock *Succ = *(Entry->succ_begin());
 
@@ -280,6 +285,12 @@ void CoreEngine::HandleBlockEdge(const BlockEdge &L, ExplodedNode *Pred) {
   const CFGBlock *Blk = L.getDst();
   NodeBuilderContext BuilderCtx(*this, Blk, Pred);
 
+  // Mark this block as visited.
+  const LocationContext *LC = Pred->getLocationContext();
+  FunctionSummaries->markVisitedBasicBlock(Blk->getBlockID(),
+                                           LC->getDecl(),
+                                           LC->getCFG()->getNumBlockIDs());
+
   // Check if we are entering the EXIT block.
   if (Blk == &(L.getLocationContext()->getCFG()->getExit())) {
 
@@ -312,10 +323,11 @@ void CoreEngine::HandleBlockEntrance(const BlockEntrance &L,
                                        ExplodedNode *Pred) {
 
   // Increment the block counter.
+  const LocationContext *LC = Pred->getLocationContext();
+  unsigned BlockId = L.getBlock()->getBlockID();
   BlockCounter Counter = WList->getBlockCounter();
-  Counter = BCounterFactory.IncrementCount(Counter, 
-                             Pred->getLocationContext()->getCurrentStackFrame(),
-                                           L.getBlock()->getBlockID());
+  Counter = BCounterFactory.IncrementCount(Counter, LC->getCurrentStackFrame(),
+                                           BlockId);
   WList->setBlockCounter(Counter);
 
   // Process the entrance of the block.
diff --git a/lib/StaticAnalyzer/Core/ExprEngine.cpp b/lib/StaticAnalyzer/Core/ExprEngine.cpp
index 35c751a89d..70921c5a7c 100644
--- a/lib/StaticAnalyzer/Core/ExprEngine.cpp
+++ b/lib/StaticAnalyzer/Core/ExprEngine.cpp
@@ -71,7 +71,7 @@ ExprEngine::ExprEngine(AnalysisManager &mgr, bool gcEnabled,
                        FunctionSummariesTy *FS)
   : AMgr(mgr),
     AnalysisDeclContexts(mgr.getAnalysisDeclContextManager()),
-    Engine(*this, VisitedCallees),
+    Engine(*this, VisitedCallees, FS),
     G(Engine.getGraph()),
     StateMgr(getContext(), mgr.getStoreManagerCreator(),
              mgr.getConstraintManagerCreator(), G.getAllocator(),
@@ -82,7 +82,7 @@ ExprEngine::ExprEngine(AnalysisManager &mgr, bool gcEnabled,
     currentStmt(NULL), currentStmtIdx(0), currentBuilderContext(0),
     NSExceptionII(NULL), NSExceptionInstanceRaiseSelectors(NULL),
     RaiseSel(GetNullarySelector("raise", getContext())),
-    ObjCGCEnabled(gcEnabled), BR(mgr, *this), FunctionSummaries(FS) {
+    ObjCGCEnabled(gcEnabled), BR(mgr, *this) {
   
   if (mgr.shouldEagerlyTrimExplodedGraph()) {
     // Enable eager node reclaimation when constructing the ExplodedGraph.  
@@ -1051,7 +1051,7 @@ void ExprEngine::processCFGBlockEntrance(const BlockEdge &L,
     const LocationContext *RootLC =
                         (*G.roots_begin())->getLocation().getLocationContext();
     if (RootLC->getCurrentStackFrame() != CalleeSF) {
-      FunctionSummaries->markReachedMaxBlockCount(CalleeSF->getDecl());
+      Engine.FunctionSummaries->markReachedMaxBlockCount(CalleeSF->getDecl());
 
       // Re-run the call evaluation without inlining it, by storing the
       // no-inlining policy in the state and enqueuing the new work item on
diff --git a/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp b/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
index 272f13eb6b..b99bd5441e 100644
--- a/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
+++ b/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp
@@ -138,7 +138,7 @@ bool ExprEngine::shouldInlineDecl(const FunctionDecl *FD, ExplodedNode *Pred) {
         == AMgr.InlineMaxStackDepth)
     return false;
 
-  if (FunctionSummaries->hasReachedMaxBlockCount(FD))
+  if (Engine.FunctionSummaries->hasReachedMaxBlockCount(FD))
     return false;
 
   if (CalleeCFG->getNumBlockIDs() > AMgr.InlineMaxFunctionSize)
diff --git a/lib/StaticAnalyzer/Core/FunctionSummary.cpp b/lib/StaticAnalyzer/Core/FunctionSummary.cpp
new file mode 100644
index 0000000000..c227aac2b4
--- /dev/null
+++ b/lib/StaticAnalyzer/Core/FunctionSummary.cpp
@@ -0,0 +1,38 @@
+//== FunctionSummary.h - Stores summaries of functions. ------------*- C++ -*-//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines a summary of a function gathered/used by static analyzes.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/StaticAnalyzer/Core/PathSensitive/FunctionSummary.h"
+using namespace clang;
+using namespace ento;
+
+FunctionSummariesTy::~FunctionSummariesTy() {
+  for (MapTy::iterator I = Map.begin(), E = Map.end(); I != E; ++I) {
+    delete(I->second);
+  }
+}
+
+unsigned FunctionSummariesTy::getTotalNumBasicBlocks() {
+  unsigned Total = 0;
+  for (MapTy::iterator I = Map.begin(), E = Map.end(); I != E; ++I) {
+    Total += I->second->TotalBasicBlocks;
+  }
+  return Total;
+}
+
+unsigned FunctionSummariesTy::getTotalNumVisitedBasicBlocks() {
+  unsigned Total = 0;
+  for (MapTy::iterator I = Map.begin(), E = Map.end(); I != E; ++I) {
+    Total += I->second->VisitedBasicBlocks.count();
+  }
+  return Total;
+}
diff --git a/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp b/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
index 3b9deda2ba..df2d265cad 100644
--- a/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
+++ b/lib/StaticAnalyzer/Frontend/AnalysisConsumer.cpp
@@ -53,6 +53,9 @@ static ExplodedNode::Auditor* CreateUbiViz();
 
 STATISTIC(NumFunctionTopLevel, "The # of functions at top level.");
 STATISTIC(NumFunctionsAnalyzed, "The # of functions analysed (as top level).");
+STATISTIC(NumBlocksInAnalyzedFunctions,
+                     "The # of basic blocks in the analyzed functions.");
+STATISTIC(PercentReachableBlocks, "The % of reachable basic blocks.");
 
 //===----------------------------------------------------------------------===//
 // Special PathDiagnosticConsumers.
@@ -122,6 +125,13 @@ public:
   }
 
   ~AnalysisConsumer() {
+    // Count how many basic blocks we have not covered.
+    NumBlocksInAnalyzedFunctions = FunctionSummaries.getTotalNumBasicBlocks();
+    if (NumBlocksInAnalyzedFunctions > 0)
+      PercentReachableBlocks =
+        (FunctionSummaries.getTotalNumVisitedBasicBlocks() * 100) /
+          NumBlocksInAnalyzedFunctions;
+
     if (Opts.PrintStats)
       delete TUTotalTimer;
   }
diff --git a/test/Analysis/stats.c b/test/Analysis/stats.c
index 8ba812193c..6beadbeb41 100644
--- a/test/Analysis/stats.c
+++ b/test/Analysis/stats.c
@@ -4,4 +4,5 @@ void foo() {
   int x;
 }
 // CHECK: ... Statistics Collected ...
+// CHECK:100 AnalysisConsumer - The % of reachable basic blocks.
 // CHECK:The # of times RemoveDeadBindings is called