diff --git a/llvm/lib/Bytecode/Reader/ReaderInternals.h b/llvm/lib/Bytecode/Reader/ReaderInternals.h
new file mode 100644
index 0000000..3bb0472
--- /dev/null
+++ b/llvm/lib/Bytecode/Reader/ReaderInternals.h
@@ -0,0 +1,146 @@
+//===-- ReaderInternals.h - Definitions internal to the reader ---*- C++ -*--=//
+//
+//  This header file defines various stuff that is used by the bytecode reader.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef READER_INTERNALS_H
+#define READER_INTERNALS_H
+
+#include "llvm/Bytecode/Primitives.h"
+#include "llvm/SymTabValue.h"
+#include "llvm/Method.h"
+#include "llvm/Instruction.h"
+#include <map>
+#include <utility>
+
+class BasicBlock;
+class Method;
+class Module;
+class Type;
+
+typedef unsigned char uchar;
+
+struct RawInst {       // The raw fields out of the bytecode stream...
+  unsigned NumOperands;
+  unsigned Opcode;
+  const Type *Ty;
+  unsigned Arg1, Arg2;
+  union {
+    unsigned Arg3;
+    vector<unsigned> *VarArgs;   // Contains arg #3,4,5... if NumOperands > 3
+  };
+};
+
+class BytecodeParser {
+public:
+  BytecodeParser() {
+    // Define this in case we don't see a ModuleGlobalInfo block.
+    FirstDerivedTyID = Type::FirstDerivedTyID;
+  }
+
+  Module *ParseBytecode(const uchar *Buf, const uchar *EndBuf);
+private:          // All of this data is transient across calls to ParseBytecode
+  typedef vector<Value *> ValueList;
+  typedef vector<ValueList> ValueTable;
+  typedef map<const Type *, unsigned> TypeMapType;
+  ValueTable Values, LateResolveValues;
+  ValueTable ModuleValues, LateResolveModuleValues;
+  TypeMapType TypeMap;
+
+  // Information read from the ModuleGlobalInfo section of the file...
+  unsigned FirstDerivedTyID;
+
+  // When the ModuleGlobalInfo section is read, we load the type of each method
+  // and the 'ModuleValues' slot that it lands in.  We then load a placeholder
+  // into its slot to reserve it.  When the method is loaded, this placeholder
+  // is replaced.
+  //
+  list<pair<const MethodType *, unsigned> > MethodSignatureList;
+
+private:
+  bool ParseModule            (const uchar * Buf, const uchar *End, Module *&);
+  bool ParseModuleGlobalInfo  (const uchar *&Buf, const uchar *End, Module *);
+  bool ParseSymbolTable       (const uchar *&Buf, const uchar *End);
+  bool ParseMethod            (const uchar *&Buf, const uchar *End, Module *);
+  bool ParseBasicBlock    (const uchar *&Buf, const uchar *End, BasicBlock *&);
+  bool ParseInstruction   (const uchar *&Buf, const uchar *End, Instruction *&);
+  bool ParseRawInst       (const uchar *&Buf, const uchar *End, RawInst &);
+
+  bool ParseConstantPool(const uchar *&Buf, const uchar *EndBuf,
+			 SymTabValue::ConstantPoolType &CP, ValueTable &Tab);
+
+
+  bool parseConstPoolValue(const uchar *&Buf, const uchar *End,
+			   const Type *Ty, ConstPoolVal *&V);
+  bool parseTypeConstant  (const uchar *&Buf, const uchar *, ConstPoolVal *&);
+
+  Value      *getValue(const Type *Ty, unsigned num, bool Create = true);
+  const Type *getType(unsigned ID);
+
+  bool insertValue(Value *D, vector<ValueList> &D);
+  bool postResolveValues(ValueTable &ValTab);
+
+  bool getTypeSlot(const Type *Ty, unsigned &Slot);
+};
+
+template<class SuperType>
+class PlaceholderDef : public SuperType {
+  unsigned ID;
+public:
+  PlaceholderDef(const Type *Ty, unsigned id) : SuperType(Ty), ID(id) {}
+  unsigned getID() { return ID; }
+};
+
+struct InstPlaceHolderHelper : public Instruction {
+  InstPlaceHolderHelper(const Type *Ty) : Instruction(Ty, UserOp1, "") {}
+  inline virtual void dropAllReferences() {}
+  virtual string getOpcode() const { return "placeholder"; }
+
+  virtual Instruction *clone() const { abort(); return 0; }
+
+  // No "operands"...
+  virtual Value *getOperand(unsigned i) { return 0; }
+  virtual const Value *getOperand(unsigned i) const { return 0; }
+  virtual bool setOperand(unsigned i, Value *Val) { return false; }
+  virtual unsigned getNumOperands() const { return 0; }
+};
+
+struct BBPlaceHolderHelper : public BasicBlock {
+  BBPlaceHolderHelper(const Type *Ty) : BasicBlock() {
+    assert(Ty->isLabelType());
+  }
+};
+
+struct MethPlaceHolderHelper : public Method {
+  MethPlaceHolderHelper(const Type *Ty) 
+    : Method((const MethodType*)Ty) {
+    assert(Ty->isMethodType() && "Method placeholders must be method types!");
+  }
+};
+
+typedef PlaceholderDef<InstPlaceHolderHelper>  DefPHolder;
+typedef PlaceholderDef<BBPlaceHolderHelper>    BBPHolder;
+typedef PlaceholderDef<MethPlaceHolderHelper>  MethPHolder;
+
+static inline unsigned getValueIDNumberFromPlaceHolder(Value *Def) {
+  switch (Def->getType()->getPrimitiveID()) {
+  case Type::LabelTyID:  return ((BBPHolder*)Def)->getID();
+  case Type::MethodTyID: return ((MethPHolder*)Def)->getID();
+  default:               return ((DefPHolder*)Def)->getID();
+  }
+}
+
+static inline bool readBlock(const uchar *&Buf, const uchar *EndBuf, 
+			     unsigned &Type, unsigned &Size) {
+#if DEBUG_OUTPUT
+  bool Result = read(Buf, EndBuf, Type) || read(Buf, EndBuf, Size);
+  cerr << "StartLoc = " << ((unsigned)Buf & 4095)
+       << " Type = " << Type << " Size = " << Size << endl;
+  return Result;
+#else
+  return read(Buf, EndBuf, Type) || read(Buf, EndBuf, Size);
+#endif
+}
+
+#endif