Commit For New Tool: llvm-abcd (Analysis of ByteCode Dumper). This tool

will (eventually) provide statistical analysis of bytecode files as well
as the ability to dump them in a low level format (slot numbers not
resolved). The purpose of this is to aid in the Type!=Value change of
bug 122. With this initial release, llvm-abcd merely dumps out the
bytecode. However, the infrastructure for separating bytecode parsing from
handling the parsing events is in place. The style chosen is similar to
SAX XML parsing where a handler object is called to handlign the parsing
events. This probably isn't useful to anyone but me right now as there is
no analysis yet, and the dumper doesn't work on every bytecode file. It
will probably be useful by the end of this week. Note that there is some
duplication of code from the bytecode reader.  This was done to eliminate
errors from being introduced in the reader and to minimize the impact to
other LLVM developers. At some point, the Analyzer and the Reader will be
integrated to use the same infrastructure. Also, sorry for the minor change
to Instruction.h but I just couldn't bring myself to write code that
depends on Instruction internals.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14048 91177308-0d34-0410-b5e6-96231b3b80d8

22 files changed, 4577 insertions, 3 deletions

diff --git a/include/llvm/Bytecode/Analyzer.h b/include/llvm/Bytecode/Analyzer.h
new file mode 100644
index 0000000000..d3e1b95503
--- /dev/null
+++ b/include/llvm/Bytecode/Analyzer.h
@@ -0,0 +1,97 @@
+//===-- llvm/Bytecode/Analyzer.h - Analyzer for bytecode files --*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under the 
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This functionality is implemented by the lib/Bytecode/Analysis library.
+// This library is used to read VM bytecode files from an iostream and print
+// out a diagnostic analysis of the contents of the file. It is intended for
+// three uses: (a) understanding the bytecode format, (b) ensuring correctness
+// of bytecode format, (c) statistical analysis of generated bytecode files.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_BYTECODE_ANALYZER_H
+#define LLVM_BYTECODE_ANALYZER_H
+
+#include <string>
+#include <map>
+
+namespace llvm {
+
+/// This structure is used to contain the output of the Bytecode Analysis 
+/// library. It simply contains fields to hold each item of the analysis 
+/// results.
+/// @brief Bytecode Analysis results structure
+struct BytecodeAnalysis {
+  unsigned byteSize;            ///< The size of the bytecode file in bytes
+  unsigned numTypes;        ///< The number of types
+  unsigned numValues;       ///< The number of values
+  unsigned numFunctions;    ///< The number of functions defined
+  unsigned numConstants;    ///< The number of constants
+  unsigned numGlobalVars;   ///< The number of global variables
+  unsigned numInstructions; ///< The number of instructions in all functions
+  unsigned numBasicBlocks;  ///< The number of BBs in all functions
+  unsigned numOperands;     ///< The number of BBs in all functions
+  unsigned maxTypeSlot;     ///< The maximum slot number for types
+  unsigned maxValueSlot;    ///< The maximum slot number for values
+  double   density;         ///< Density of file (bytes/defs) 
+
+  /// A structure that contains various pieces of information related to
+  /// an analysis of a single function.
+  struct BytecodeFunctionInfo {
+    unsigned byteSize;        ///< The size of the function in bytecode bytes
+    unsigned numInstructions; ///< The number of instructions in the function
+    unsigned numBasicBlocks;  ///< The number of basic blocks in the function
+    unsigned numOperands;     ///< The number of operands in the function
+    double density;           ///< Density of function
+    double vbrEffectiveness;  ///< Effectiveness of variable bit rate encoding.
+    ///< This is the average number of bytes per unsigned value written in the
+    ///< vbr encoding. A "perfect" score of 1.0 means all vbr values were 
+    ///< encoded in one byte. A score between 1.0 and 4.0 means that some
+    ///< savings were achieved. A score of 4.0 means vbr didn't help. A score
+    ///< greater than 4.0 means vbr negatively impacted size of the file.
+  };
+
+  /// A mapping of function names to the collected information about the 
+  /// function.
+  std::map<std::string,BytecodeFunctionInfo> FunctionInfo; 
+
+  /// Flags for what should be done
+  bool dumpBytecode;
+};
+
+/// This function is the main entry point into the bytecode analysis library. It
+/// allows you to simply provide a \P filename and storage for the \P Results 
+/// that will be filled in with the analysis results.
+/// @brief Analyze contents of a bytecode File
+void AnalyzeBytecodeFile(
+      const std::string& Filename, ///< The name of the bytecode file to read
+      BytecodeAnalysis& Results,   ///< The results of the analysis
+      std::string* ErrorStr = 0    ///< Errors, if any.
+    );
+
+/// This function is an alternate entry point into the bytecode analysis
+/// library. It allows you to provide an arbitrary memory buffer which is
+/// assumed to contain a complete bytecode file. The \P Buffer is analyzed and
+/// the \P Results are filled in.
+/// @brief Analyze contents of a bytecode buffer.
+void AnalyzeBytecodeBuffer(
+       const unsigned char* Buffer, ///< Pointer to start of bytecode buffer
+       unsigned BufferSize,         ///< Size of the bytecode buffer
+       BytecodeAnalysis& Results,   ///< The results of the analysis
+       std::string* ErrorStr = 0    ///< Errors, if any.
+     );
+
+/// This function prints the contents of rhe BytecodeAnalysis structure in
+/// a human legible form.
+/// @brief Print BytecodeAnalysis structure to an ostream
+void PrintBytecodeAnalysis(BytecodeAnalysis& bca, std::ostream& Out );
+
+} // End llvm namespace
+
+#endif
diff --git a/include/llvm/Instruction.h b/include/llvm/Instruction.h
index 17eec871f7..caba4afd8b 100644
--- a/include/llvm/Instruction.h
+++ b/include/llvm/Instruction.h
@@ -87,9 +87,14 @@ public:
   }
   static const char* getOpcodeName(unsigned OpCode);
 
+  static inline bool isTerminator(unsigned OpCode) {
+    return OpCode >= TermOpsBegin && OpCode < TermOpsEnd;
+  }
+
   inline bool isTerminator() const {   // Instance of TerminatorInst?
-    return iType >= TermOpsBegin && iType < TermOpsEnd;
+    return isTerminator(iType);
   }
+
   inline bool isBinaryOp() const {
     return iType >= BinaryOpsBegin && iType < BinaryOpsEnd;
   }
diff --git a/lib/Bytecode/Analyzer/Analyzer.cpp b/lib/Bytecode/Analyzer/Analyzer.cpp
new file mode 100644
index 0000000000..99c3e41f9f
--- /dev/null
+++ b/lib/Bytecode/Analyzer/Analyzer.cpp
@@ -0,0 +1,242 @@
+//===-- BytecodeHandler.cpp - Parsing Handler -------------------*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under the 
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+//  This header file defines the BytecodeHandler class that gets called by the
+//  AbstractBytecodeParser when parsing events occur.
+//
+//===----------------------------------------------------------------------===//
+
+#include "AnalyzerInternals.h"
+
+using namespace llvm;
+
+
+namespace {
+
+class AnalyzerHandler : public BytecodeHandler {
+public:
+  bool handleError(const std::string& str )
+  {
+    return false;
+  }
+
+  void handleStart()
+  {
+  }
+
+  void handleFinish()
+  {
+  }
+
+  void handleModuleBegin(const std::string& id)
+  {
+  }
+
+  void handleModuleEnd(const std::string& id)
+  {
+  }
+
+  void handleVersionInfo(
+    unsigned char RevisionNum,        ///< Byte code revision number
+    Module::Endianness Endianness,    ///< Endianness indicator
+    Module::PointerSize PointerSize   ///< PointerSize indicator
+  )
+  {
+  }
+
+  void handleModuleGlobalsBegin()
+  {
+  }
+
+  void handleGlobalVariable( 
+    const Type* ElemType,     ///< The type of the global variable
+    bool isConstant,          ///< Whether the GV is constant or not
+    GlobalValue::LinkageTypes ///< The linkage type of the GV
+  )
+  {
+  }
+
+  void handleInitializedGV( 
+    const Type* ElemType,     ///< The type of the global variable
+    bool isConstant,          ///< Whether the GV is constant or not
+    GlobalValue::LinkageTypes,///< The linkage type of the GV
+    unsigned initSlot         ///< Slot number of GV's initializer
+  )
+  {
+  }
+
+  virtual void handleType( const Type* Ty ) 
+  {
+  }
+
+  void handleFunctionDeclaration( 
+    const Type* FuncType      ///< The type of the function
+  )
+  {
+  }
+
+  void handleModuleGlobalsEnd()
+  {
+  }
+
+  void handleCompactionTableBegin()
+  {
+  }
+
+  void handleCompactionTablePlane( 
+    unsigned Ty, 
+    unsigned NumEntries
+  )
+  {
+  }
+
+  void handleCompactionTableType( 
+    unsigned i, 
+    unsigned TypSlot, 
+    const Type* 
+  )
+  {
+  }
+
+  void handleCompactionTableValue( 
+    unsigned i, 
+    unsigned ValSlot, 
+    const Type* 
+  )
+  {
+  }
+
+  void handleCompactionTableEnd()
+  {
+  }
+
+  void handleSymbolTableBegin()
+  {
+  }
+
+  void handleSymbolTablePlane( 
+    unsigned Ty, 
+    unsigned NumEntries, 
+    const Type* Typ
+  )
+  {
+  }
+
+  void handleSymbolTableType( 
+    unsigned i, 
+    unsigned slot, 
+    const std::string& name 
+  )
+  {
+  }
+
+  void handleSymbolTableValue( 
+    unsigned i, 
+    unsigned slot, 
+    const std::string& name 
+  )
+  {
+  }
+
+  void handleSymbolTableEnd()
+  {
+  }
+
+  void handleFunctionBegin(
+    const Type* FType, 
+    GlobalValue::LinkageTypes linkage 
+  )
+  {
+  }
+
+  void handleFunctionEnd(
+    const Type* FType
+  )
+  {
+  }
+
+  void handleBasicBlockBegin(
+    unsigned blocknum
+  )
+  {
+  }
+
+  bool handleInstruction(
+    unsigned Opcode, 
+    const Type* iType, 
+    std::vector<unsigned>& Operands
+  )
+  {
+    return false;
+  }
+
+  void handleBasicBlockEnd(unsigned blocknum)
+  {
+  }
+
+  void handleGlobalConstantsBegin()
+  {
+  }
+
+  void handleConstantExpression( 
+      unsigned Opcode, 
+      const Type* Typ, 
+      std::vector<std::pair<const Type*,unsigned> > ArgVec 
+    )
+  {
+  }
+
+  void handleConstantValue( Constant * c )
+  {
+  }
+
+  void handleConstantArray( 
+	  const ArrayType* AT, 
+	  std::vector<unsigned>& Elements )
+  {
+  }
+
+  void handleConstantStruct(
+	const StructType* ST,
+	std::vector<unsigned>& ElementSlots)
+  {
+  }
+
+  void handleConstantPointer(
+	const PointerType* PT, unsigned Slot)
+  {
+  }
+
+  void handleConstantString( const ConstantArray* CA ) 
+  {
+  }
+
+
+  void handleGlobalConstantsEnd()
+  {
+  }
+
+};
+
+}
+
+void llvm::BytecodeAnalyzer::AnalyzeBytecode(
+    const unsigned char *Buf, 
+    unsigned Length,
+    BytecodeAnalysis& bca,
+    const std::string &ModuleID
+)
+{
+  AnalyzerHandler TheHandler;
+  AbstractBytecodeParser TheParser(&TheHandler);
+  TheParser.ParseBytecode( Buf, Length, ModuleID );
+  TheParser.ParseAllFunctionBodies();
+}
+
+// vim: sw=2
diff --git a/lib/Bytecode/Analyzer/AnalyzerInternals.h b/lib/Bytecode/Analyzer/AnalyzerInternals.h
new file mode 100644
index 0000000000..d9a2e843d8
--- /dev/null
+++ b/lib/Bytecode/Analyzer/AnalyzerInternals.h
@@ -0,0 +1,65 @@
+//===-- ReaderInternals.h - Definitions internal to the reader --*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+//  This header file defines various stuff that is used by the bytecode reader.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef ANALYZER_INTERNALS_H
+#define ANALYZER_INTERNALS_H
+
+#include "Parser.h"
+#include "llvm/Bytecode/Analyzer.h"
+
+// Enable to trace to figure out what the heck is going on when parsing fails
+//#define TRACE_LEVEL 10
+//#define DEBUG_OUTPUT
+
+#if TRACE_LEVEL    // ByteCodeReading_TRACEr
+#define BCR_TRACE(n, X) \
+    if (n < TRACE_LEVEL) std::cerr << std::string(n*2, ' ') << X
+#else
+#define BCR_TRACE(n, X)
+#endif
+
+namespace llvm {
+
+class BytecodeAnalyzer {
+  BytecodeAnalyzer(const BytecodeAnalyzer &);  // DO NOT IMPLEMENT
+  void operator=(const BytecodeAnalyzer &);  // DO NOT IMPLEMENT
+public:
+  BytecodeAnalyzer() { }
+  ~BytecodeAnalyzer() { }
+
+  void AnalyzeBytecode(
+    const unsigned char *Buf, 
+    unsigned Length,
+    BytecodeAnalysis& bca,
+    const std::string &ModuleID
+  );
+
+  void DumpBytecode(
+    const unsigned char *Buf, 
+    unsigned Length,
+    BytecodeAnalysis& bca,
+    const std::string &ModuleID
+  );
+
+  void dump() const {
+    std::cerr << "BytecodeParser instance!\n";
+  }
+private:
+  BytecodeAnalysis TheAnalysis;
+};
+
+} // End llvm namespace
+
+#endif
+
+// vim: sw=2
diff --git a/lib/Bytecode/Analyzer/AnalyzerWrappers.cpp b/lib/Bytecode/Analyzer/AnalyzerWrappers.cpp
new file mode 100644
index 0000000000..a0e4845a1b
--- /dev/null
+++ b/lib/Bytecode/Analyzer/AnalyzerWrappers.cpp
@@ -0,0 +1,208 @@
+//===- AnalyzerWrappers.cpp - Analyze bytecode from file or buffer  -------===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under the
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This file implements loading and analysis of a bytecode file and analyzing a
+// bytecode buffer.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Bytecode/Analyzer.h"
+#include "AnalyzerInternals.h"
+#include "Support/FileUtilities.h"
+#include "Support/StringExtras.h"
+#include "Config/unistd.h"
+#include <cerrno>
+
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// BytecodeFileAnalyzer - Analyze from an mmap'able file descriptor.
+//
+
+namespace {
+  /// BytecodeFileAnalyzer - parses a bytecode file from a file
+  class BytecodeFileAnalyzer : public BytecodeAnalyzer {
+  private:
+    unsigned char *Buffer;
+    unsigned Length;
+
+    BytecodeFileAnalyzer(const BytecodeFileAnalyzer&); // Do not implement
+    void operator=(const BytecodeFileAnalyzer &BFR); // Do not implement
+
+  public:
+    BytecodeFileAnalyzer(const std::string &Filename, BytecodeAnalysis& bca);
+    ~BytecodeFileAnalyzer();
+  };
+}
+
+static std::string ErrnoMessage (int savedErrNum, std::string descr) {
+   return ::strerror(savedErrNum) + std::string(", while trying to ") + descr;
+}
+
+BytecodeFileAnalyzer::BytecodeFileAnalyzer(const std::string &Filename, 
+	                                   BytecodeAnalysis& bca) {
+  Buffer = (unsigned char*)ReadFileIntoAddressSpace(Filename, Length);
+  if (Buffer == 0)
+    throw "Error reading file '" + Filename + "'.";
+
+  try {
+    // Parse the bytecode we mmapped in
+    if ( bca.dumpBytecode ) 
+      DumpBytecode(Buffer, Length, bca, Filename);
+    AnalyzeBytecode(Buffer, Length, bca, Filename);
+  } catch (...) {
+    UnmapFileFromAddressSpace(Buffer, Length);
+    throw;
+  }
+}
+
+BytecodeFileAnalyzer::~BytecodeFileAnalyzer() {
+  // Unmmap the bytecode...
+  UnmapFileFromAddressSpace(Buffer, Length);
+}
+
+//===----------------------------------------------------------------------===//
+// BytecodeBufferAnalyzer - Read from a memory buffer
+//
+
+namespace {
+  /// BytecodeBufferAnalyzer - parses a bytecode file from a buffer
+  ///
+  class BytecodeBufferAnalyzer : public BytecodeAnalyzer {
+  private:
+    const unsigned char *Buffer;
+    bool MustDelete;
+
+    BytecodeBufferAnalyzer(const BytecodeBufferAnalyzer&); // Do not implement
+    void operator=(const BytecodeBufferAnalyzer &BFR);   // Do not implement
+
+  public:
+    BytecodeBufferAnalyzer(const unsigned char *Buf, unsigned Length,
+	                   BytecodeAnalysis& bca, const std::string &ModuleID);
+    ~BytecodeBufferAnalyzer();
+
+  };
+}
+
+BytecodeBufferAnalyzer::BytecodeBufferAnalyzer(const unsigned char *Buf,
+					       unsigned Length,
+					       BytecodeAnalysis& bca,
+					       const std::string &ModuleID) {
+  // If not aligned, allocate a new buffer to hold the bytecode...
+  const unsigned char *ParseBegin = 0;
+  if ((intptr_t)Buf & 3) {
+    Buffer = new unsigned char[Length+4];
+    unsigned Offset = 4 - ((intptr_t)Buffer & 3);   // Make sure it's aligned
+    ParseBegin = Buffer + Offset;
+    memcpy((unsigned char*)ParseBegin, Buf, Length);    // Copy it over
+    MustDelete = true;
+  } else {
+    // If we don't need to copy it over, just use the caller's copy
+    ParseBegin = Buffer = Buf;
+    MustDelete = false;
+  }
+  try {
+    if ( bca.dumpBytecode ) 
+      DumpBytecode(ParseBegin, Length, bca, ModuleID);
+    AnalyzeBytecode(ParseBegin, Length, bca, ModuleID);
+  } catch (...) {
+    if (MustDelete) delete [] Buffer;
+    throw;
+  }
+}
+
+BytecodeBufferAnalyzer::~BytecodeBufferAnalyzer() {
+  if (MustDelete) delete [] Buffer;
+}
+
+//===----------------------------------------------------------------------===//
+//  BytecodeStdinAnalyzer - Read bytecode from Standard Input
+//
+
+namespace {
+  /// BytecodeStdinAnalyzer - parses a bytecode file from stdin
+  /// 
+  class BytecodeStdinAnalyzer : public BytecodeAnalyzer {
+  private:
+    std::vector<unsigned char> FileData;
+    unsigned char *FileBuf;
+
+    BytecodeStdinAnalyzer(const BytecodeStdinAnalyzer&); // Do not implement
+    void operator=(const BytecodeStdinAnalyzer &BFR);  // Do not implement
+
+  public:
+    BytecodeStdinAnalyzer(BytecodeAnalysis& bca);
+  };
+}
+
+BytecodeStdinAnalyzer::BytecodeStdinAnalyzer(BytecodeAnalysis& bca ) {
+  int BlockSize;
+  unsigned char Buffer[4096*4];
+
+  // Read in all of the data from stdin, we cannot mmap stdin...
+  while ((BlockSize = ::read(0 /*stdin*/, Buffer, 4096*4))) {
+    if (BlockSize == -1)
+      throw ErrnoMessage(errno, "read from standard input");
+    
+    FileData.insert(FileData.end(), Buffer, Buffer+BlockSize);
+  }
+
+  if (FileData.empty())
+    throw std::string("Standard Input empty!");
+
+  FileBuf = &FileData[0];
+  if (bca.dumpBytecode)
+    DumpBytecode(&FileData[0], FileData.size(), bca, "<stdin>");
+  AnalyzeBytecode(FileBuf, FileData.size(), bca, "<stdin>");
+}
+
+//===----------------------------------------------------------------------===//
+// Wrapper functions
+//===----------------------------------------------------------------------===//
+
+// AnalyzeBytecodeFile - analyze one file
+void llvm::AnalyzeBytecodeFile(const std::string &Filename, 
+                               BytecodeAnalysis& bca,
+                               std::string *ErrorStr) 
+{
+  try {
+    if ( Filename != "-" )
+      BytecodeFileAnalyzer bfa(Filename,bca);
+    else
+      BytecodeStdinAnalyzer bsa(bca);
+  } catch (std::string &err) {
+    if (ErrorStr) *ErrorStr = err;
+  }
+}
+
+// AnalyzeBytecodeBuffer - analyze a buffer
+void llvm::AnalyzeBytecodeBuffer(
+       const unsigned char* Buffer, ///< Pointer to start of bytecode buffer
+       unsigned BufferSize,         ///< Size of the bytecode buffer
+       BytecodeAnalysis& Results,   ///< The results of the analysis
+       std::string* ErrorStr        ///< Errors, if any.
+     ) 
+{
+  try {
+    BytecodeBufferAnalyzer(Buffer, BufferSize, Results, "<buffer>" );
+  } catch (std::string& err ) {
+    if ( ErrorStr) *ErrorStr = err;
+  }
+}
+
+
+/// This function prints the contents of rhe BytecodeAnalysis structure in
+/// a human legible form.
+/// @brief Print BytecodeAnalysis structure to an ostream
+void llvm::PrintBytecodeAnalysis(BytecodeAnalysis& bca, std::ostream& Out )
+{
+  Out << "Not Implemented Yet.\n";
+}
+
+// vim: sw=2
diff --git a/lib/Bytecode/Analyzer/BytecodeHandler.cpp b/lib/Bytecode/Analyzer/BytecodeHandler.cpp
new file mode 100644
index 0000000000..2415958867
--- /dev/null
+++ b/lib/Bytecode/Analyzer/BytecodeHandler.cpp
@@ -0,0 +1,220 @@
+//===-- BytecodeHandler.cpp - Parsing Handler -------------------*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under the 
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+//  This header file defines the BytecodeHandler class that gets called by the
+//  AbstractBytecodeParser when parsing events occur.
+//
+//===----------------------------------------------------------------------===//
+
+#include "BytecodeHandler.h"
+
+using namespace llvm;
+
+bool BytecodeHandler::handleError(const std::string& str )
+{
+  return false;
+}
+
+void BytecodeHandler::handleStart()
+{
+}
+
+void BytecodeHandler::handleFinish()
+{
+}
+
+void BytecodeHandler::handleModuleBegin(const std::string& id)
+{
+}
+
+void BytecodeHandler::handleModuleEnd(const std::string& id)
+{
+}
+
+void BytecodeHandler::handleVersionInfo(
+  unsigned char RevisionNum,        ///< Byte code revision number
+  Module::Endianness Endianness,    ///< Endianness indicator
+  Module::PointerSize PointerSize   ///< PointerSize indicator
+)
+{
+}
+
+void BytecodeHandler::handleModuleGlobalsBegin()
+{
+}
+
+void BytecodeHandler::handleGlobalVariable( 
+  const Type* ElemType,     ///< The type of the global variable
+  bool isConstant,          ///< Whether the GV is constant or not
+  GlobalValue::LinkageTypes ///< The linkage type of the GV
+)
+{
+}
+
+void BytecodeHandler::handleInitializedGV( 
+  const Type* ElemType,     ///< The type of the global variable
+  bool isConstant,          ///< Whether the GV is constant or not
+  GlobalValue::LinkageTypes,///< The linkage type of the GV
+  unsigned initSlot         ///< Slot number of GV's initializer
+)
+{
+}
+
+void BytecodeHandler::handleType( const Type* Ty ) 
+{
+}
+
+void BytecodeHandler::handleFunctionDeclaration( 
+  const Type* FuncType      ///< The type of the function
+)
+{
+}
+
+void BytecodeHandler::handleModuleGlobalsEnd()
+{
+}
+
+void BytecodeHandler::handleCompactionTableBegin()
+{
+}
+
+void BytecodeHandler::handleCompactionTablePlane( 
+  unsigned Ty, 
+  unsigned NumEntries
+)
+{
+}
+
+void BytecodeHandler::handleCompactionTableType( 
+  unsigned i, 
+  unsigned TypSlot, 
+  const Type* 
+)
+{
+}
+
+void BytecodeHandler::handleCompactionTableValue( 
+  unsigned i, 
+  unsigned ValSlot, 
+  const Type* 
+)
+{
+}
+
+void BytecodeHandler::handleCompactionTableEnd()
+{
+}
+
+void BytecodeHandler::handleSymbolTableBegin()
+{
+}
+
+void BytecodeHandler::handleSymbolTablePlane( 
+  unsigned Ty, 
+  unsigned NumEntries, 
+  const Type* Typ
+)
+{
+}
+
+void BytecodeHandler::handleSymbolTableType( 
+  unsigned i, 
+  unsigned slot, 
+  const std::string& name 
+)
+{
+}
+
+void BytecodeHandler::handleSymbolTableValue( 
+  unsigned i, 
+  unsigned slot, 
+  const std::string& name 
+)
+{
+}
+
+void BytecodeHandler::handleSymbolTableEnd()
+{
+}
+
+void BytecodeHandler::handleFunctionBegin(
+  const Type* FType, 
+  GlobalValue::LinkageTypes linkage 
+)
+{
+}
+
+void BytecodeHandler::handleFunctionEnd(
+  const Type* FType
+)
+{
+}
+
+void BytecodeHandler::handleBasicBlockBegin(
+  unsigned blocknum
+)
+{
+}
+
+bool BytecodeHandler::handleInstruction(
+  unsigned Opcode, 
+  const Type* iType, 
+  std::vector<unsigned>& Operands
+)
+{
+  return false;
+}
+
+void BytecodeHandler::handleBasicBlockEnd(unsigned blocknum)
+{
+}
+
+void BytecodeHandler::handleGlobalConstantsBegin()
+{
+}
+
+void BytecodeHandler::handleConstantExpression( 
+    unsigned Opcode, 
+    const Type* Typ, 
+    std::vector<std::pair<const Type*,unsigned> > ArgVec 
+  )
+{
+}
+
+void BytecodeHandler::handleConstantValue( Constant * c )
+{
+}
+
+void BytecodeHandler::handleConstantArray( 
+        const ArrayType* AT, 
+        std::vector<unsigned>& Elements )
+{
+}
+
+void BytecodeHandler::handleConstantStruct(
+      const StructType* ST,
+      std::vector<unsigned>& ElementSlots)
+{
+}
+
+void BytecodeHandler::handleConstantPointer(
+      const PointerType* PT, unsigned Slot)
+{
+}
+
+void BytecodeHandler::handleConstantString( const ConstantArray* CA ) 
+{
+}
+
+
+void BytecodeHandler::handleGlobalConstantsEnd()
+{
+}
+
+// vim: sw=2
diff --git a/lib/Bytecode/Analyzer/BytecodeHandler.h b/lib/Bytecode/Analyzer/BytecodeHandler.h
new file mode 100644
index 0000000000..2b03e2d332
--- /dev/null
+++ b/lib/Bytecode/Analyzer/BytecodeHandler.h
@@ -0,0 +1,247 @@
+//===-- BytecodeHandler.h - Parsing Handler ---------------------*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer and is distributed under the 
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+//  This header file defines the BytecodeHandler class that gets called by the
+//  AbstractBytecodeParser when parsing events occur.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef BYTECODE_HANDLER_H
+#define BYTECODE_HANDLER_H
+
+#include "llvm/Module.h"
+#include "llvm/GlobalValue.h"
+#include <vector>
+
+namespace llvm {
+
+class ArrayType;
+class StructType;
+class PointerType;
+class ConstantArray;
+
+/// This class provides the interface for the handling bytecode events during
+/// parsing. The methods on this interface are invoked by the 
+/// AbstractBytecodeParser as it discovers the content of a bytecode stream. 
+/// This class provides a a clear separation of concerns between recognizing 
+/// the semantic units of a bytecode file and deciding what to do with them. 
+/// The AbstractBytecodeParser recognizes the content of the bytecode file and
+/// calls the BytecodeHandler methods to determine what should be done. This
+/// arrangement allows Bytecode files to be read and handled for a number of
+/// purposes simply by creating a subclass of BytecodeHandler. None of the
+/// parsing details need to be understood, only the meaning of the calls
+/// made on this interface.
+/// 
+/// Another paradigm that uses this design pattern is the XML SAX Parser. The
+/// ContentHandler for SAX plays the same role as the BytecodeHandler here.
+/// @brief Handle Bytecode Parsing Events
+class BytecodeHandler {
+
+/// @name Constructors And Operators
+/// @{
+public:
+  /// @brief Default constructor (empty)
+  BytecodeHandler() {}
+  /// @brief Virtual