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diff --git a/include/llvm/IR/Constant.h b/include/llvm/IR/Constant.h
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+//===-- llvm/Constant.h - Constant class definition -------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the declaration of the Constant class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CONSTANT_H
+#define LLVM_CONSTANT_H
+
+#include "llvm/IR/User.h"
+
+namespace llvm {
+  class APInt;
+
+  template<typename T> class SmallVectorImpl;
+
+/// This is an important base class in LLVM. It provides the common facilities
+/// of all constant values in an LLVM program. A constant is a value that is
+/// immutable at runtime. Functions are constants because their address is
+/// immutable. Same with global variables. 
+/// 
+/// All constants share the capabilities provided in this class. All constants
+/// can have a null value. They can have an operand list. Constants can be
+/// simple (integer and floating point values), complex (arrays and structures),
+/// or expression based (computations yielding a constant value composed of 
+/// only certain operators and other constant values).
+/// 
+/// Note that Constants are immutable (once created they never change) 
+/// and are fully shared by structural equivalence.  This means that two 
+/// structurally equivalent constants will always have the same address.  
+/// Constants are created on demand as needed and never deleted: thus clients 
+/// don't have to worry about the lifetime of the objects.
+/// @brief LLVM Constant Representation
+class Constant : public User {
+  void operator=(const Constant &) LLVM_DELETED_FUNCTION;
+  Constant(const Constant &) LLVM_DELETED_FUNCTION;
+  virtual void anchor();
+  
+protected:
+  Constant(Type *ty, ValueTy vty, Use *Ops, unsigned NumOps)
+    : User(ty, vty, Ops, NumOps) {}
+
+  void destroyConstantImpl();
+public:
+  /// isNullValue - Return true if this is the value that would be returned by
+  /// getNullValue.
+  bool isNullValue() const;
+
+  /// isAllOnesValue - Return true if this is the value that would be returned by
+  /// getAllOnesValue.
+  bool isAllOnesValue() const;
+
+  /// isNegativeZeroValue - Return true if the value is what would be returned 
+  /// by getZeroValueForNegation.
+  bool isNegativeZeroValue() const;
+
+  /// canTrap - Return true if evaluation of this constant could trap.  This is
+  /// true for things like constant expressions that could divide by zero.
+  bool canTrap() const;
+
+  /// isThreadDependent - Return true if the value can vary between threads.
+  bool isThreadDependent() const;
+
+  /// isConstantUsed - Return true if the constant has users other than constant
+  /// exprs and other dangling things.
+  bool isConstantUsed() const;
+  
+  enum PossibleRelocationsTy {
+    NoRelocation = 0,
+    LocalRelocation = 1,
+    GlobalRelocations = 2
+  };
+  
+  /// getRelocationInfo - This method classifies the entry according to
+  /// whether or not it may generate a relocation entry.  This must be
+  /// conservative, so if it might codegen to a relocatable entry, it should say
+  /// so.  The return values are:
+  /// 
+  ///  NoRelocation: This constant pool entry is guaranteed to never have a
+  ///     relocation applied to it (because it holds a simple constant like
+  ///     '4').
+  ///  LocalRelocation: This entry has relocations, but the entries are
+  ///     guaranteed to be resolvable by the static linker, so the dynamic
+  ///     linker will never see them.
+  ///  GlobalRelocations: This entry may have arbitrary relocations.
+  ///
+  /// FIXME: This really should not be in VMCore.
+  PossibleRelocationsTy getRelocationInfo() const;
+  
+  /// getAggregateElement - For aggregates (struct/array/vector) return the
+  /// constant that corresponds to the specified element if possible, or null if
+  /// not.  This can return null if the element index is a ConstantExpr, or if
+  /// 'this' is a constant expr.
+  Constant *getAggregateElement(unsigned Elt) const;
+  Constant *getAggregateElement(Constant *Elt) const;
+
+  /// getSplatValue - If this is a splat vector constant, meaning that all of
+  /// the elements have the same value, return that value. Otherwise return 0.
+  Constant *getSplatValue() const;
+
+  /// If C is a constant integer then return its value, otherwise C must be a
+  /// vector of constant integers, all equal, and the common value is returned.
+  const APInt &getUniqueInteger() const;
+
+  /// destroyConstant - Called if some element of this constant is no longer
+  /// valid.  At this point only other constants may be on the use_list for this
+  /// constant.  Any constants on our Use list must also be destroy'd.  The
+  /// implementation must be sure to remove the constant from the list of
+  /// available cached constants.  Implementations should call
+  /// destroyConstantImpl as the last thing they do, to destroy all users and
+  /// delete this.
+  virtual void destroyConstant() { llvm_unreachable("Not reached!"); }
+
+  //// Methods for support type inquiry through isa, cast, and dyn_cast:
+  static inline bool classof(const Value *V) {
+    return V->getValueID() >= ConstantFirstVal &&
+           V->getValueID() <= ConstantLastVal;
+  }
+
+  /// replaceUsesOfWithOnConstant - This method is a special form of
+  /// User::replaceUsesOfWith (which does not work on constants) that does work
+  /// on constants.  Basically this method goes through the trouble of building
+  /// a new constant that is equivalent to the current one, with all uses of
+  /// From replaced with uses of To.  After this construction is completed, all
+  /// of the users of 'this' are replaced to use the new constant, and then
+  /// 'this' is deleted.  In general, you should not call this method, instead,
+  /// use Value::replaceAllUsesWith, which automatically dispatches to this
+  /// method as needed.
+  ///
+  virtual void replaceUsesOfWithOnConstant(Value *, Value *, Use *) {
+    // Provide a default implementation for constants (like integers) that
+    // cannot use any other values.  This cannot be called at runtime, but needs
+    // to be here to avoid link errors.
+    assert(getNumOperands() == 0 && "replaceUsesOfWithOnConstant must be "
+           "implemented for all constants that have operands!");
+    llvm_unreachable("Constants that do not have operands cannot be using "
+                     "'From'!");
+  }
+
+  static Constant *getNullValue(Type* Ty);
+
+  /// @returns the value for an integer or vector of integer constant of the
+  /// given type that has all its bits set to true.
+  /// @brief Get the all ones value
+  static Constant *getAllOnesValue(Type* Ty);
+
+  /// getIntegerValue - Return the value for an integer or pointer constant,
+  /// or a vector thereof, with the given scalar value.
+  static Constant *getIntegerValue(Type* Ty, const APInt &V);
+  
+  /// removeDeadConstantUsers - If there are any dead constant users dangling
+  /// off of this constant, remove them.  This method is useful for clients
+  /// that want to check to see if a global is unused, but don't want to deal
+  /// with potentially dead constants hanging off of the globals.
+  void removeDeadConstantUsers() const;
+};
+
+} // End llvm namespace
+
+#endif