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diff --git a/include/llvm/IR/CFG.h b/include/llvm/IR/CFG.h
new file mode 100644
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+++ b/include/llvm/IR/CFG.h
@@ -0,0 +1,383 @@
+//===- CFG.h - Process LLVM structures as graphs ----------------*- 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 specializations of GraphTraits that allow Function and
+// BasicBlock graphs to be treated as proper graphs for generic algorithms.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_IR_CFG_H
+#define LLVM_IR_CFG_H
+
+#include "llvm/ADT/GraphTraits.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/InstrTypes.h"
+
+namespace llvm {
+
+//===----------------------------------------------------------------------===//
+// BasicBlock pred_iterator definition
+//===----------------------------------------------------------------------===//
+
+template <class Ptr, class USE_iterator> // Predecessor Iterator
+class PredIterator : public std::iterator<std::forward_iterator_tag,
+                                          Ptr, ptrdiff_t, Ptr*, Ptr*> {
+  typedef std::iterator<std::forward_iterator_tag, Ptr, ptrdiff_t, Ptr*,
+                                                                    Ptr*> super;
+  typedef PredIterator<Ptr, USE_iterator> Self;
+  USE_iterator It;
+
+  inline void advancePastNonTerminators() {
+    // Loop to ignore non-terminator uses (for example BlockAddresses).
+    while (!It.atEnd() && !isa<TerminatorInst>(*It))
+      ++It;
+  }
+
+public:
+  typedef typename super::pointer pointer;
+  typedef typename super::reference reference;
+
+  PredIterator() {}
+  explicit inline PredIterator(Ptr *bb) : It(bb->use_begin()) {
+    advancePastNonTerminators();
+  }
+  inline PredIterator(Ptr *bb, bool) : It(bb->use_end()) {}
+
+  inline bool operator==(const Self& x) const { return It == x.It; }
+  inline bool operator!=(const Self& x) const { return !operator==(x); }
+
+  inline reference operator*() const {
+    assert(!It.atEnd() && "pred_iterator out of range!");
+    return cast<TerminatorInst>(*It)->getParent();
+  }
+  inline pointer *operator->() const { return &operator*(); }
+
+  inline Self& operator++() {   // Preincrement
+    assert(!It.atEnd() && "pred_iterator out of range!");
+    ++It; advancePastNonTerminators();
+    return *this;
+  }
+
+  inline Self operator++(int) { // Postincrement
+    Self tmp = *this; ++*this; return tmp;
+  }
+
+  /// getOperandNo - Return the operand number in the predecessor's
+  /// terminator of the successor.
+  unsigned getOperandNo() const {
+    return It.getOperandNo();
+  }
+
+  /// getUse - Return the operand Use in the predecessor's terminator
+  /// of the successor.
+  Use &getUse() const {
+    return It.getUse();
+  }
+};
+
+typedef PredIterator<BasicBlock, Value::use_iterator> pred_iterator;
+typedef PredIterator<const BasicBlock,
+                     Value::const_use_iterator> const_pred_iterator;
+
+inline pred_iterator pred_begin(BasicBlock *BB) { return pred_iterator(BB); }
+inline const_pred_iterator pred_begin(const BasicBlock *BB) {
+  return const_pred_iterator(BB);
+}
+inline pred_iterator pred_end(BasicBlock *BB) { return pred_iterator(BB, true);}
+inline const_pred_iterator pred_end(const BasicBlock *BB) {
+  return const_pred_iterator(BB, true);
+}
+
+
+
+//===----------------------------------------------------------------------===//
+// BasicBlock succ_iterator definition
+//===----------------------------------------------------------------------===//
+
+template <class Term_, class BB_>           // Successor Iterator
+class SuccIterator : public std::iterator<std::random_access_iterator_tag, BB_,
+                                          int, BB_ *, BB_ *> {
+  typedef std::iterator<std::random_access_iterator_tag, BB_, int, BB_ *, BB_ *>
+  super;
+
+public:
+  typedef typename super::pointer pointer;
+  typedef typename super::reference reference;
+
+private:
+  const Term_ Term;
+  unsigned idx;
+  typedef SuccIterator<Term_, BB_> Self;
+
+  inline bool index_is_valid(int idx) {
+    return idx >= 0 && (unsigned) idx < Term->getNumSuccessors();
+  }
+
+  /// \brief Proxy object to allow write access in operator[]
+  class SuccessorProxy {
+    Self it;
+
+  public:
+    explicit SuccessorProxy(const Self &it) : it(it) {}
+
+    SuccessorProxy &operator=(SuccessorProxy r) {
+      *this = reference(r);
+      return *this;
+    }
+
+    SuccessorProxy &operator=(reference r) {
+      it.Term->setSuccessor(it.idx, r);
+      return *this;
+    }
+
+    operator reference() const { return *it; }
+  };
+
+public:
+  explicit inline SuccIterator(Term_ T) : Term(T), idx(0) {// begin iterator
+  }
+  inline SuccIterator(Term_ T, bool)                       // end iterator
+    : Term(T) {
+    if (Term)
+      idx = Term->getNumSuccessors();
+    else
+      // Term == NULL happens, if a basic block is not fully constructed and
+      // consequently getTerminator() returns NULL. In this case we construct a
+      // SuccIterator which describes a basic block that has zero successors.
+      // Defining SuccIterator for incomplete and malformed CFGs is especially
+      // useful for debugging.
+      idx = 0;
+  }
+
+  inline const Self &operator=(const Self &I) {
+    assert(Term == I.Term &&"Cannot assign iterators to two different blocks!");
+    idx = I.idx;
+    return *this;
+  }
+
+  /// getSuccessorIndex - This is used to interface between code that wants to
+  /// operate on terminator instructions directly.
+  unsigned getSuccessorIndex() const { return idx; }
+
+  inline bool operator==(const Self& x) const { return idx == x.idx; }
+  inline bool operator!=(const Self& x) const { return !operator==(x); }
+
+  inline reference operator*() const { return Term->getSuccessor(idx); }
+  inline pointer operator->() const { return operator*(); }
+
+  inline Self& operator++() { ++idx; return *this; } // Preincrement
+
+  inline Self operator++(int) { // Postincrement
+    Self tmp = *this; ++*this; return tmp;
+  }
+
+  inline Self& operator--() { --idx; return *this; }  // Predecrement
+  inline Self operator--(int) { // Postdecrement
+    Self tmp = *this; --*this; return tmp;
+  }
+
+  inline bool operator<(const Self& x) const {
+    assert(Term == x.Term && "Cannot compare iterators of different blocks!");
+    return idx < x.idx;
+  }
+
+  inline bool operator<=(const Self& x) const {
+    assert(Term == x.Term && "Cannot compare iterators of different blocks!");
+    return idx <= x.idx;
+  }
+  inline bool operator>=(const Self& x) const {
+    assert(Term == x.Term && "Cannot compare iterators of different blocks!");
+    return idx >= x.idx;
+  }
+
+  inline bool operator>(const Self& x) const {
+    assert(Term == x.Term && "Cannot compare iterators of different blocks!");
+    return idx > x.idx;
+  }
+
+  inline Self& operator+=(int Right) {
+    unsigned new_idx = idx + Right;
+    assert(index_is_valid(new_idx) && "Iterator index out of bound");
+    idx = new_idx;
+    return *this;
+  }
+
+  inline Self operator+(int Right) const {
+    Self tmp = *this;
+    tmp += Right;
+    return tmp;
+  }
+
+  inline Self& operator-=(int Right) {
+    return operator+=(-Right);
+  }
+
+  inline Self operator-(int Right) const {
+    return operator+(-Right);
+  }
+
+  inline int operator-(const Self& x) const {
+    assert(Term == x.Term && "Cannot work on iterators of different blocks!");
+    int distance = idx - x.idx;
+    return distance;
+  }
+
+  inline SuccessorProxy operator[](int offset) {
+   Self tmp = *this;
+   tmp += offset;
+   return SuccessorProxy(tmp);
+  }
+
+  /// Get the source BB of this iterator.
+  inline BB_ *getSource() {
+    assert(Term && "Source not available, if basic block was malformed");
+    return Term->getParent();
+  }
+};
+
+typedef SuccIterator<TerminatorInst*, BasicBlock> succ_iterator;
+typedef SuccIterator<const TerminatorInst*,
+                     const BasicBlock> succ_const_iterator;
+
+inline succ_iterator succ_begin(BasicBlock *BB) {
+  return succ_iterator(BB->getTerminator());
+}
+inline succ_const_iterator succ_begin(const BasicBlock *BB) {
+  return succ_const_iterator(BB->getTerminator());
+}
+inline succ_iterator succ_end(BasicBlock *BB) {
+  return succ_iterator(BB->getTerminator(), true);
+}
+inline succ_const_iterator succ_end(const BasicBlock *BB) {
+  return succ_const_iterator(BB->getTerminator(), true);
+}
+
+template <typename T, typename U> struct isPodLike<SuccIterator<T, U> > {
+  static const bool value = isPodLike<T>::value;
+};
+
+
+
+//===--------------------------------------------------------------------===//
+// GraphTraits specializations for basic block graphs (CFGs)
+//===--------------------------------------------------------------------===//
+
+// Provide specializations of GraphTraits to be able to treat a function as a
+// graph of basic blocks...
+
+template <> struct GraphTraits<BasicBlock*> {
+  typedef BasicBlock NodeType;
+  typedef succ_iterator ChildIteratorType;
+
+  static NodeType *getEntryNode(BasicBlock *BB) { return BB; }
+  static inline ChildIteratorType child_begin(NodeType *N) {
+    return succ_begin(N);
+  }
+  static inline ChildIteratorType child_end(NodeType *N) {
+    return succ_end(N);
+  }
+};
+
+template <> struct GraphTraits<const BasicBlock*> {
+  typedef const BasicBlock NodeType;
+  typedef succ_const_iterator ChildIteratorType;
+
+  static NodeType *getEntryNode(const BasicBlock *BB) { return BB; }
+
+  static inline ChildIteratorType child_begin(NodeType *N) {
+    return succ_begin(N);
+  }
+  static inline ChildIteratorType child_end(NodeType *N) {
+    return succ_end(N);
+  }
+};
+
+// Provide specializations of GraphTraits to be able to treat a function as a
+// graph of basic blocks... and to walk it in inverse order.  Inverse order for
+// a function is considered to be when traversing the predecessor edges of a BB
+// instead of the successor edges.
+//
+template <> struct GraphTraits<Inverse<BasicBlock*> > {
+  typedef BasicBlock NodeType;
+  typedef pred_iterator ChildIteratorType;
+  static NodeType *getEntryNode(Inverse<BasicBlock *> G) { return G.Graph; }
+  static inline ChildIteratorType child_begin(NodeType *N) {
+    return pred_begin(N);
+  }
+  static inline ChildIteratorType child_end(NodeType *N) {
+    return pred_end(N);
+  }
+};
+
+template <> struct GraphTraits<Inverse<const BasicBlock*> > {
+  typedef const BasicBlock NodeType;
+  typedef const_pred_iterator ChildIteratorType;
+  static NodeType *getEntryNode(Inverse<const BasicBlock*> G) {
+    return G.Graph;
+  }
+  static inline ChildIteratorType child_begin(NodeType *N) {
+    return pred_begin(N);
+  }
+  static inline ChildIteratorType child_end(NodeType *N) {
+    return pred_end(N);
+  }
+};
+
+
+
+//===--------------------------------------------------------------------===//
+// GraphTraits specializations for function basic block graphs (CFGs)
+//===--------------------------------------------------------------------===//
+
+// Provide specializations of GraphTraits to be able to treat a function as a
+// graph of basic blocks... these are the same as the basic block iterators,
+// except that the root node is implicitly the first node of the function.
+//
+template <> struct GraphTraits<Function*> : public GraphTraits<BasicBlock*> {
+  static NodeType *getEntryNode(Function *F) { return &F->getEntryBlock(); }
+
+  // nodes_iterator/begin/end - Allow iteration over all nodes in the graph
+  typedef Function::iterator nodes_iterator;
+  static nodes_iterator nodes_begin(Function *F) { return F->begin(); }
+  static nodes_iterator nodes_end  (Function *F) { return F->end(); }
+  static size_t         size       (Function *F) { return F->size(); }
+};
+template <> struct GraphTraits<const Function*> :
+  public GraphTraits<const BasicBlock*> {
+  static NodeType *getEntryNode(const Function *F) {return &F->getEntryBlock();}
+
+  // nodes_iterator/begin/end - Allow iteration over all nodes in the graph
+  typedef Function::const_iterator nodes_iterator;
+  static nodes_iterator nodes_begin(const Function *F) { return F->begin(); }
+  static nodes_iterator nodes_end  (const Function *F) { return F->end(); }
+  static size_t         size       (const Function *F) { return F->size(); }
+};
+
+
+// Provide specializations of GraphTraits to be able to treat a function as a
+// graph of basic blocks... and to walk it in inverse order.  Inverse order for
+// a function is considered to be when traversing the predecessor edges of a BB
+// instead of the successor edges.
+//
+template <> struct GraphTraits<Inverse<Function*> > :
+  public GraphTraits<Inverse<BasicBlock*> > {
+  static NodeType *getEntryNode(Inverse<Function*> G) {
+    return &G.Graph->getEntryBlock();
+  }
+};
+template <> struct GraphTraits<Inverse<const Function*> > :
+  public GraphTraits<Inverse<const BasicBlock*> > {
+  static NodeType *getEntryNode(Inverse<const Function *> G) {
+    return &G.Graph->getEntryBlock();
+  }
+};
+
+} // End llvm namespace
+
+#endif