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diff --git a/include/clang/Analysis/Analyses/LiveVariables.h b/include/clang/Analysis/Analyses/LiveVariables.h
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+++ b/include/clang/Analysis/Analyses/LiveVariables.h
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+//===- LiveVariables.h - Live Variable Analysis for Source CFGs -*- C++ --*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements Live Variables analysis for source-level CFGs.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIVEVARIABLES_H
+#define LLVM_CLANG_LIVEVARIABLES_H
+
+#include "clang/AST/Decl.h"
+#include "clang/Analysis/Support/BlkExprDeclBitVector.h"
+#include "clang/Analysis/FlowSensitive/DataflowValues.h"
+
+namespace clang {
+
+class Stmt;
+class DeclRefExpr;
+class SourceManager;
+  
+struct LiveVariables_ValueTypes {
+
+  struct ObserverTy;
+
+  // We keep dataflow state for declarations and block-level expressions;
+  typedef StmtDeclBitVector_Types::ValTy ValTy;
+
+  // We need to keep track of both declarations and CFGBlock-level expressions,
+  // (so that we don't explore such expressions twice).  We also want
+  // to compute liveness information for block-level expressions, since these
+  // act as "temporary" values.
+  
+  struct AnalysisDataTy : public StmtDeclBitVector_Types::AnalysisDataTy {
+    ObserverTy* Observer;
+    ValTy AlwaysLive;
+    
+    AnalysisDataTy() : Observer(NULL) {}
+  };
+  
+  //===-----------------------------------------------------===//
+  // ObserverTy - Observer for uninitialized values queries.
+  //===-----------------------------------------------------===//
+
+  struct ObserverTy {
+    virtual ~ObserverTy() {}
+    
+    /// ObserveStmt - A callback invoked right before invoking the
+    ///  liveness transfer function on the given statement.
+    virtual void ObserveStmt(Stmt* S, const AnalysisDataTy& AD, 
+                             const ValTy& V) {}
+    
+    virtual void ObserverKill(DeclRefExpr* DR) {}
+  };
+};
+
+class LiveVariables : public DataflowValues<LiveVariables_ValueTypes,
+                                            dataflow::backward_analysis_tag> {
+                                              
+                                              
+public:
+  typedef LiveVariables_ValueTypes::ObserverTy ObserverTy;
+    
+  LiveVariables(ASTContext& Ctx, CFG& cfg);
+  
+  /// IsLive - Return true if a variable is live at beginning of a
+  /// specified block.
+  bool isLive(const CFGBlock* B, const VarDecl* D) const;
+                                              
+  /// IsLive - Returns true if a variable is live at the beginning of the
+  ///  the statement.  This query only works if liveness information
+  ///  has been recorded at the statement level (see runOnAllBlocks), and
+  ///  only returns liveness information for block-level expressions.
+  bool isLive(const Stmt* S, const VarDecl* D) const;
+                                              
+  /// IsLive - Returns true the block-level expression "value" is live
+  ///  before the given block-level expression (see runOnAllBlocks).
+  bool isLive(const Stmt* Loc, const Stmt* StmtVal) const;
+  
+  /// IsLive - Return true if a variable is live according to the
+  ///  provided livness bitvector.
+  bool isLive(const ValTy& V, const VarDecl* D) const;
+  
+  /// dumpLiveness - Print to stderr the liveness information encoded
+  ///  by a specified bitvector.
+  void dumpLiveness(const ValTy& V, SourceManager& M) const;
+  
+  /// dumpBlockLiveness - Print to stderr the liveness information
+  ///  associated with each basic block.
+  void dumpBlockLiveness(SourceManager& M) const;
+  
+  /// getNumDecls - Return the number of variables (declarations) that
+  ///  whose liveness status is being tracked by the dataflow
+  ///  analysis.
+  unsigned getNumDecls() const { return getAnalysisData().getNumDecls(); }
+    
+  /// IntializeValues - This routine can perform extra initialization, but
+  ///  for LiveVariables this does nothing since all that logic is in
+  ///  the constructor.                                              
+  void InitializeValues(const CFG& cfg) {}
+  
+  void runOnCFG(CFG& cfg);
+                                              
+  /// runOnAllBlocks - Propagate the dataflow values once for each block,
+  ///  starting from the current dataflow values.  'recordStmtValues' indicates
+  ///  whether the method should store dataflow values per each individual
+  ///  block-level expression.
+  void runOnAllBlocks(const CFG& cfg, ObserverTy* Obs,
+                      bool recordStmtValues=false);
+};
+
+} // end namespace clang
+
+#endif