3 files changed, 46 insertions, 1 deletions

diff --git a/include/clang/Analysis/ProgramPoint.h b/include/clang/Analysis/ProgramPoint.h
index 5de06cd3a5..e66022c876 100644
--- a/include/clang/Analysis/ProgramPoint.h
+++ b/include/clang/Analysis/ProgramPoint.h
@@ -461,6 +461,7 @@ public:
 };
 
 /// Represents a point when we begin processing an inlined call.
+/// CallEnter uses the caller's location context.
 class CallEnter : public ProgramPoint {
 public:
   CallEnter(const Stmt *stmt, const StackFrameContext *calleeCtx, 
diff --git a/include/clang/StaticAnalyzer/Core/BugReporter/BugReporter.h b/include/clang/StaticAnalyzer/Core/BugReporter/BugReporter.h
index 48393a379b..c8581e2e23 100644
--- a/include/clang/StaticAnalyzer/Core/BugReporter/BugReporter.h
+++ b/include/clang/StaticAnalyzer/Core/BugReporter/BugReporter.h
@@ -24,6 +24,7 @@
 #include "llvm/ADT/ilist_node.h"
 #include "llvm/ADT/ImmutableSet.h"
 #include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/SmallSet.h"
 
 namespace clang {
 
@@ -95,6 +96,10 @@ protected:
   /// for multiple PathDiagnosticConsumers.
   llvm::SmallVector<Regions *, 2> interestingRegions;
 
+  /// A set of location contexts that correspoind to call sites which should be
+  /// considered "interesting".
+  llvm::SmallSet<const LocationContext *, 2> InterestingLocationContexts;
+
   /// A set of custom visitors which generate "event" diagnostics at
   /// interesting points in the path.
   VisitorList Callbacks;
@@ -172,10 +177,12 @@ public:
   void markInteresting(SymbolRef sym);
   void markInteresting(const MemRegion *R);
   void markInteresting(SVal V);
+  void markInteresting(const LocationContext *LC);
   
   bool isInteresting(SymbolRef sym);
   bool isInteresting(const MemRegion *R);
   bool isInteresting(SVal V);
+  bool isInteresting(const LocationContext *LC);
 
   unsigned getConfigurationChangeToken() const {
     return ConfigurationChangeToken;
@@ -342,6 +349,11 @@ private:
   /// A vector of BugReports for tracking the allocated pointers and cleanup.
   std::vector<BugReportEquivClass *> EQClassesVector;
 
+  /// A map from PathDiagnosticPiece to the LocationContext of the inlined
+  /// function call it represents.
+  llvm::DenseMap<const PathDiagnosticCallPiece*,
+                 const LocationContext*> LocationContextMap;
+
 protected:
   BugReporter(BugReporterData& d, Kind k) : BugTypes(F.getEmptySet()), kind(k),
                                             D(d) {}
@@ -382,6 +394,8 @@ public:
                                       PathDiagnosticConsumer &PC,
                                       ArrayRef<BugReport *> &bugReports) {}
 
+  bool RemoveUneededCalls(PathPieces &pieces, BugReport *R);
+
   void Register(BugType *BT);
 
   /// \brief Add the given report to the set of reports tracked by BugReporter.
@@ -411,6 +425,10 @@ public:
 
   static bool classof(const BugReporter* R) { return true; }
 
+  void addCallPieceLocationContextPair(const PathDiagnosticCallPiece *C,
+                                       const LocationContext *LC) {
+    LocationContextMap[C] = LC;
+  }
 private:
   llvm::StringMap<BugType *> StrBugTypes;
 
diff --git a/include/clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h b/include/clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h
index e82b5233d7..f3206964e3 100644
--- a/include/clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h
+++ b/include/clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitor.h
@@ -222,7 +222,33 @@ public:
                     const ExplodedNode *N,
                     llvm::Optional<bool> &prunable);
 };
-  
+
+/// \brief When a region containing undefined value or '0' value is passed 
+/// as an argument in a call, marks the call as interesting.
+///
+/// As a result, BugReporter will not prune the path through the function even
+/// if the region's contents are not modified/accessed by the call.
+class UndefOrNullArgVisitor
+  : public BugReporterVisitorImpl<UndefOrNullArgVisitor> {
+
+  /// The interesting memory region this visitor is tracking.
+  const MemRegion *R;
+
+public:
+  UndefOrNullArgVisitor(const MemRegion *InR) : R(InR) {}
+
+  virtual void Profile(llvm::FoldingSetNodeID &ID) const {
+    static int Tag = 0;
+    ID.AddPointer(&Tag);
+    ID.AddPointer(R);
+  }
+
+  PathDiagnosticPiece *VisitNode(const ExplodedNode *N,
+                                 const ExplodedNode *PrevN,
+                                 BugReporterContext &BRC,
+                                 BugReport &BR);
+};
+
 namespace bugreporter {
 
 void trackNullOrUndefValue(const ExplodedNode *N, const Stmt *S, BugReport &R);