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diff --git a/include/llvm/Analysis/IVUsers.h b/include/llvm/Analysis/IVUsers.h
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+//===- llvm/Analysis/IVUsers.h - Induction Variable Users -------*- 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 bookkeeping for "interesting" users of expressions
+// computed from induction variables.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_IVUSERS_H
+#define LLVM_ANALYSIS_IVUSERS_H
+
+#include "llvm/Analysis/LoopPass.h"
+#include "llvm/Analysis/ScalarEvolution.h"
+#include <llvm/ADT/SmallVector.h>
+#include <map>
+
+namespace llvm {
+
+class DominatorTree;
+class Instruction;
+class Value;
+class IVUsersOfOneStride;
+
+/// IVStrideUse - Keep track of one use of a strided induction variable, where
+/// the stride is stored externally.  The Offset member keeps track of the
+/// offset from the IV, User is the actual user of the operand, and
+/// 'OperandValToReplace' is the operand of the User that is the use.
+class IVStrideUse : public CallbackVH, public ilist_node<IVStrideUse> {
+public:
+  IVStrideUse(IVUsersOfOneStride *parent,
+              const SCEVHandle &offset,
+              Instruction* U, Value *O, bool issigned)
+    : CallbackVH(U), Parent(parent), Offset(offset),
+      OperandValToReplace(O), IsSigned(issigned),
+      IsUseOfPostIncrementedValue(false) {
+  }
+
+  /// getUser - Return the user instruction for this use.
+  Instruction *getUser() const {
+    return cast<Instruction>(getValPtr());
+  }
+
+  /// setUser - Assign a new user instruction for this use.
+  void setUser(Instruction *NewUser) {
+    setValPtr(NewUser);
+  }
+
+  /// getParent - Return a pointer to the IVUsersOfOneStride that owns
+  /// this IVStrideUse.
+  IVUsersOfOneStride *getParent() const { return Parent; }
+
+  /// getOffset - Return the offset to add to a theoeretical induction
+  /// variable that starts at zero and counts up by the stride to compute
+  /// the value for the use. This always has the same type as the stride,
+  /// which may need to be casted to match the type of the use.
+  SCEVHandle getOffset() const { return Offset; }
+
+  /// setOffset - Assign a new offset to this use.
+  void setOffset(SCEVHandle Val) {
+    Offset = Val;
+  }
+
+  /// getOperandValToReplace - Return the Value of the operand in the user
+  /// instruction that this IVStrideUse is representing.
+  Value *getOperandValToReplace() const {
+    return OperandValToReplace;
+  }
+
+  /// setOperandValToReplace - Assign a new Value as the operand value
+  /// to replace.
+  void setOperandValToReplace(Value *Op) {
+    OperandValToReplace = Op;
+  }
+
+  /// isSigned - The stride (and thus also the Offset) of this use may be in
+  /// a narrower type than the use itself (OperandValToReplace->getType()).
+  /// When this is the case, isSigned() indicates whether the IV expression
+  /// should be signed-extended instead of zero-extended to fit the type of
+  /// the use.
+  bool isSigned() const { return IsSigned; }
+
+  /// isUseOfPostIncrementedValue - True if this should use the
+  /// post-incremented version of this IV, not the preincremented version.
+  /// This can only be set in special cases, such as the terminating setcc
+  /// instruction for a loop or uses dominated by the loop.
+  bool isUseOfPostIncrementedValue() const {
+    return IsUseOfPostIncrementedValue;
+  }
+
+  /// setIsUseOfPostIncrmentedValue - set the flag that indicates whether
+  /// this is a post-increment use.
+  void setIsUseOfPostIncrementedValue(bool Val) {
+    IsUseOfPostIncrementedValue = Val;
+  }
+
+private:
+  /// Parent - a pointer to the IVUsersOfOneStride that owns this IVStrideUse.
+  IVUsersOfOneStride *Parent;
+
+  /// Offset - The offset to add to the base induction expression.
+  SCEVHandle Offset;
+
+  /// OperandValToReplace - The Value of the operand in the user instruction
+  /// that this IVStrideUse is representing.
+  WeakVH OperandValToReplace;
+
+  /// IsSigned - Determines whether the replacement value is sign or
+  /// zero extended to the type of the use.
+  bool IsSigned;
+
+  /// IsUseOfPostIncrementedValue - True if this should use the
+  /// post-incremented version of this IV, not the preincremented version.
+  bool IsUseOfPostIncrementedValue;
+
+  /// Deleted - Implementation of CallbackVH virtual function to
+  /// recieve notification when the User is deleted.
+  virtual void deleted();
+};
+
+template<> struct ilist_traits<IVStrideUse>
+  : public ilist_default_traits<IVStrideUse> {
+  // createSentinel is used to get hold of a node that marks the end of
+  // the list...
+  // The sentinel is relative to this instance, so we use a non-static
+  // method.
+  IVStrideUse *createSentinel() const {
+    // since i(p)lists always publicly derive from the corresponding
+    // traits, placing a data member in this class will augment i(p)list.
+    // But since the NodeTy is expected to publicly derive from
+    // ilist_node<NodeTy>, there is a legal viable downcast from it
+    // to NodeTy. We use this trick to superpose i(p)list with a "ghostly"
+    // NodeTy, which becomes the sentinel. Dereferencing the sentinel is
+    // forbidden (save the ilist_node<NodeTy>) so no one will ever notice
+    // the superposition.
+    return static_cast<IVStrideUse*>(&Sentinel);
+  }
+  static void destroySentinel(IVStrideUse*) {}
+
+  IVStrideUse *provideInitialHead() const { return createSentinel(); }
+  IVStrideUse *ensureHead(IVStrideUse*) const { return createSentinel(); }
+  static void noteHead(IVStrideUse*, IVStrideUse*) {}
+
+private:
+  mutable ilist_node<IVStrideUse> Sentinel;
+};
+
+/// IVUsersOfOneStride - This structure keeps track of all instructions that
+/// have an operand that is based on the trip count multiplied by some stride.
+struct IVUsersOfOneStride : public ilist_node<IVUsersOfOneStride> {
+private:
+  IVUsersOfOneStride(const IVUsersOfOneStride &I); // do not implement
+  void operator=(const IVUsersOfOneStride &I);     // do not implement
+
+public:
+  IVUsersOfOneStride() : Stride(0) {}
+
+  explicit IVUsersOfOneStride(const SCEV *stride) : Stride(stride) {}
+
+  /// Stride - The stride for all the contained IVStrideUses. This is
+  /// a constant for affine strides.
+  const SCEV *Stride;
+
+  /// Users - Keep track of all of the users of this stride as well as the
+  /// initial value and the operand that uses the IV.
+  ilist<IVStrideUse> Users;
+
+  void addUser(const SCEVHandle &Offset,Instruction *User, Value *Operand,
+               bool isSigned) {
+    Users.push_back(new IVStrideUse(this, Offset, User, Operand, isSigned));
+  }
+};
+
+class IVUsers : public LoopPass {
+  friend class IVStrideUserVH;
+  Loop *L;
+  LoopInfo *LI;
+  DominatorTree *DT;
+  ScalarEvolution *SE;
+  SmallPtrSet<Instruction*,16> Processed;
+
+public:
+  /// IVUses - A list of all tracked IV uses of induction variable expressions
+  /// we are interested in.
+  ilist<IVUsersOfOneStride> IVUses;
+
+  /// IVUsesByStride - A mapping from the strides in StrideOrder to the
+  /// uses in IVUses.
+  std::map<SCEVHandle, IVUsersOfOneStride*> IVUsesByStride;
+
+  /// StrideOrder - An ordering of the keys in IVUsesByStride that is stable:
+  /// We use this to iterate over the IVUsesByStride collection without being
+  /// dependent on random ordering of pointers in the process.
+  SmallVector<SCEVHandle, 16> StrideOrder;
+
+private:
+  virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+
+  virtual bool runOnLoop(Loop *L, LPPassManager &LPM);
+
+  virtual void releaseMemory();
+
+public:
+  static char ID; // Pass ID, replacement for typeid
+  IVUsers();
+
+  /// AddUsersIfInteresting - Inspect the specified Instruction.  If it is a
+  /// reducible SCEV, recursively add its users to the IVUsesByStride set and
+  /// return true.  Otherwise, return false.
+  bool AddUsersIfInteresting(Instruction *I);
+
+  /// getReplacementExpr - Return a SCEV expression which computes the
+  /// value of the OperandValToReplace of the given IVStrideUse.
+  SCEVHandle getReplacementExpr(const IVStrideUse &U) const;
+
+  void print(raw_ostream &OS, const Module* = 0) const;
+  virtual void print(std::ostream &OS, const Module* = 0) const;
+  void print(std::ostream *OS, const Module* M = 0) const {
+    if (OS) print(*OS, M);
+  }
+
+  /// dump - This method is used for debugging.
+  void dump() const;
+};
+
+Pass *createIVUsersPass();
+
+}
+
+#endif