For PR797:

Remove exception throwing/handling from lib/Bytecode, and adjust its users
to compensate for changes in the interface.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@29875 91177308-0d34-0410-b5e6-96231b3b80d8

10 files changed, 325 insertions, 234 deletions

diff --git a/include/llvm/Bytecode/Reader.h b/include/llvm/Bytecode/Reader.h
index c691ed0..b69932b 100644
--- a/include/llvm/Bytecode/Reader.h
+++ b/include/llvm/Bytecode/Reader.h
@@ -29,48 +29,75 @@ namespace llvm {
 // Forward declare the handler class
 class BytecodeHandler;
 
-/// getBytecodeModuleProvider - lazy function-at-a-time loading from a file
-///
+/// This function returns a ModuleProvider that can be used to do lazy 
+/// function-at-a-time loading from a bytecode file.
+/// @returns NULL on error
+/// @returns ModuleProvider* if successful
+/// @brief Get a ModuleProvide for a bytecode file.
 ModuleProvider *getBytecodeModuleProvider(
-  const std::string &Filename, ///< Name of file to be read
-  BytecodeHandler* H = 0       ///< Optional handler for reader events
+  const std::string &Filename,  ///< Name of file to be read
+  std::string* ErrMsg,          ///< Optional error message holder 
+  BytecodeHandler* H = 0        ///< Optional handler for reader events
 );
 
-/// getBytecodeBufferModuleProvider - lazy function-at-a-time loading from a
-/// buffer
-///
-ModuleProvider *getBytecodeBufferModuleProvider(const unsigned char *Buffer,
-                                                unsigned BufferSize,
-                                                const std::string &ModuleID="",
-                                                BytecodeHandler* H = 0);
+/// This function returns a ModuleProvider that can be used to do lazy 
+/// function function-at-a-time loading from a bytecode buffer.
+/// @returns NULL on error
+/// @returns ModuleProvider* if successful
+/// @brief Get a ModuleProvider for a bytecode buffer.
+ModuleProvider *getBytecodeBufferModuleProvider(
+  const unsigned char *Buffer,    ///< Start of buffer to parse
+  unsigned BufferSize,            ///< Size of the buffer
+  const std::string &ModuleID,    ///< Name to give the module
+  std::string* ErrMsg,            ///< Optional place to return an error message
+  BytecodeHandler* H              ///< Optional handler for reader events
+);
 
+/// This is the main interface to bytecode parsing. It opens the file specified
+/// by \p Filename and parses the entire file, returing the corresponding Module
+/// object if successful.
+/// @returns NULL on error
+/// @returns the module corresponding to the bytecode file, if successful
 /// @brief Parse the given bytecode file
-Module* ParseBytecodeFile(const std::string &Filename,
-                          std::string *ErrorStr = 0);
+Module* ParseBytecodeFile(
+  const std::string &Filename,    ///< Name of file to parse
+  std::string *ErrMsg = 0         ///< Optional place to return an error message
+);
 
+/// Parses a bytecode buffer specified by \p Buffer and \p BufferSize.
+/// @returns NULL on error
+/// @returns the module corresponding to the bytecode buffer, if successful
 /// @brief Parse a given bytecode buffer
-Module* ParseBytecodeBuffer(const unsigned char *Buffer,
-                            unsigned BufferSize,
-                            const std::string &ModuleID = "",
-                            std::string *ErrorStr = 0);
+Module* ParseBytecodeBuffer(
+  const unsigned char *Buffer,    ///< Start of buffer to parse
+  unsigned BufferSize,            ///< Size of the buffer
+  const std::string &ModuleID="", ///< Name to give the module
+  std::string *ErrMsg = 0         ///< Optional place to return an error message
+);
 
 /// This function will read only the necessary parts of a bytecode file in order
 /// to determine the list of dependent libraries encoded within it. The \p
 /// deplibs parameter will contain a vector of strings of the bytecode module's
 /// dependent libraries.
-/// @returns true on success, false otherwise
+/// @returns true on error, false otherwise
 /// @brief Get the list of dependent libraries from a bytecode file.
-bool GetBytecodeDependentLibraries(const std::string &fileName,
-                                   Module::LibraryListType& deplibs);
+bool GetBytecodeDependentLibraries(
+  const std::string &fileName,       ///< File name to read bytecode from
+  Module::LibraryListType& deplibs,  ///< List of dependent libraries extracted
+  std::string* ErrMsg                ///< Optional error message holder
+);
 
 /// This function will read only the necessary parts of a bytecode file in order
 /// to obtain a list of externally visible global symbols that the bytecode
 /// module defines. This is used for archiving and linking when only the list
 /// of symbols the module defines is needed.
-/// @returns true on success, false otherwise
+/// @returns true on error, false otherwise
 /// @brief Get a bytecode file's externally visibile defined global symbols.
-bool GetBytecodeSymbols(const sys::Path& fileName,
-                        std::vector<std::string>& syms);
+bool GetBytecodeSymbols(
+  const sys::Path& fileName,       ///< Filename to read bytecode from
+  std::vector<std::string>& syms,  ///< Vector to return symbols in
+  std::string* ErrMsg              ///< Optional error message holder
+);
 
 /// This function will read only the necessary parts of a bytecode buffer in
 /// order to obtain a list of externally visible global symbols that the
@@ -83,7 +110,8 @@ ModuleProvider* GetBytecodeSymbols(
   const unsigned char*Buffer,        ///< The buffer to be parsed
   unsigned Length,                   ///< The length of \p Buffer
   const std::string& ModuleID,       ///< An identifier for the module
-  std::vector<std::string>& symbols  ///< The symbols defined in the module
+  std::vector<std::string>& symbols, ///< The symbols defined in the module
+  std::string* ErrMsg                ///< Optional error message holder
 );
 
 } // End llvm namespace
diff --git a/include/llvm/Constants.h b/include/llvm/Constants.h
index ef06c33..e053029 100644
--- a/include/llvm/Constants.h
+++ b/include/llvm/Constants.h
@@ -7,13 +7,13 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This file contains the declarations for the subclasses of Constant, which
-// represent the different flavors of constant values that live in LLVM.  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.  Constant's are
-// created on demand as needed and never deleted: thus clients don't have to
-// worry about the lifetime of the objects.
+/// @file This file contains the declarations for the subclasses of Constant, 
+/// which represent the different flavors of constant values that live in LLVM.
+/// 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.  Constant's are
+/// created on demand as needed and never deleted: thus clients don't have to
+/// worry about the lifetime of the objects.
 //
 //===----------------------------------------------------------------------===//
 
@@ -36,10 +36,9 @@ template<class ConstantClass, class TypeClass>
 struct ConvertConstantType;
 
 //===----------------------------------------------------------------------===//
-/// ConstantIntegral - Shared superclass of boolean and integer constants.
-///
-/// This class just defines some common interfaces to be implemented.
-///
+/// This is the shared superclass of boolean and integer constants. This class 
+/// just defines some common interfaces to be implemented by the subclasses.
+/// @brief An abstract class for integer constants.
 class ConstantIntegral : public Constant {
 protected:
   union {
@@ -49,52 +48,66 @@ protected:
   ConstantIntegral(const Type *Ty, ValueTy VT, uint64_t V);
 public:
 
-  /// getRawValue - return the underlying value of this constant as a 64-bit
-  /// unsigned integer value.
-  ///
+  /// @brief Return the raw value of the constant as a 64-bit integer value.
   inline uint64_t getRawValue() const { return Val.Unsigned; }
   
-  /// getZExtValue - Return the constant zero extended as appropriate for this
-  /// type.
+  /// Return the constant as a 64-bit unsigned integer value after it
+  /// has been zero extended as appropriate for the type of this constant.
+  /// @brief Return the zero extended value.
   inline uint64_t getZExtValue() const {
     unsigned Size = getType()->getPrimitiveSizeInBits();
     return Val.Unsigned & (~uint64_t(0UL) >> (64-Size));
   }
 
-  /// getSExtValue - Return the constant sign extended as appropriate for this
-  /// type.
+  /// Return the constant as a 64-bit integer value after it has been sign
+  /// sign extended as appropriate for the type of this constant.
+  /// @brief REturn the sign extended value.
   inline int64_t getSExtValue() const {
     unsigned Size = getType()->getPrimitiveSizeInBits();
     return (Val.Signed << (64-Size)) >> (64-Size);
   }
   
-  /// isNullValue - Return true if this is the value that would be returned by
-  /// getNullValue.
-  ///
+  /// This function is implemented by subclasses and will return true iff this
+  /// constant represents the the "null" value that would be returned by the
+  /// getNullValue method.
+  /// @returns true if the constant's value is 0.
+  /// @brief Determine if the value is null.
   virtual bool isNullValue() const = 0;
 
-  /// isMaxValue - Return true if this is the largest value that may be
-  /// represented by this type.
-  ///
+  /// This function is implemented by sublcasses and will return true iff this
+  /// constant represents the the largest value that may be represented by this
+  /// constant's type.
+  /// @returns true if the constant's value is maximal.
+  /// @brief Determine if the value is maximal.
   virtual bool isMaxValue() const = 0;
 
-  /// isMinValue - Return true if this is the smallest value that may be
-  /// represented by this type.
-  ///
+  /// This function is implemented by subclasses and will return true iff this 
+  /// constant represents the smallest value that may be represented by this 
+  /// constant's type.
+  /// @returns true if the constant's value is minimal
+  /// @brief Determine if the value is minimal.
   virtual bool isMinValue() const = 0;
 
-  /// isAllOnesValue - Return true if every bit in this constant is set to true.
-  ///
+  /// This function is implemented by subclasses and will return true iff every
+  /// bit in this constant is set to true.
+  /// @returns true if all bits of the constant are ones.
+  /// @brief Determine if the value is all ones.
   virtual bool isAllOnesValue() const = 0;
 
-  /// Static constructor to get the maximum/minimum/allones constant of
-  /// specified (integral) type...
-  ///
+  /// @returns the largest value for an integer constant of the given type 
+  /// @brief Get the maximal value
   static ConstantIntegral *getMaxValue(const Type *Ty);
+
+  /// @returns the smallest value for an integer constant of the given type 
+  /// @brief Get the minimal value
   static ConstantIntegral *getMinValue(const Type *Ty);
+
+  /// @returns the value for an integer constant of the given type that has all
+  /// its bits set to true.
+  /// @brief Get the all ones value
   static ConstantIntegral *getAllOnesValue(const Type *Ty);
 
-  /// Methods for support type inquiry through isa, cast, and dyn_cast:
+  /// Methods to support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const ConstantIntegral *) { return true; }
   static bool classof(const Value *V) {
     return V->getValueType() == ConstantBoolVal ||
@@ -105,33 +118,41 @@ public:
 
 
 //===----------------------------------------------------------------------===//
-/// ConstantBool - Boolean Values
-///
+/// This concrete class represents constant values of type BoolTy. There are 
+/// only two instances of this class constructed: the True and False static 
+/// members. The constructor is hidden to ensure this invariant.
+/// @brief Constant Boolean class
 class ConstantBool : public ConstantIntegral {
   ConstantBool(bool V);
 public:
-  static ConstantBool *True, *False;  // The True & False values
+  static ConstantBool *True, *False;  ///< The True & False values
 
-  /// get() - Static factory methods - Return objects of the specified value
+  /// This method is provided mostly for compatibility with the other 
+  /// ConstantIntegral subclasses.
+  /// @brief Static factory method for getting a ConstantBool instance.
   static ConstantBool *get(bool Value) { return Value ? True : False; }
+
+  /// This method is provided mostly for compatibility with the other 
+  /// ConstantIntegral subclasses.
+  /// @brief Static factory method for getting a ConstantBool instance.
   static ConstantBool *get(const Type *Ty, bool Value) { return get(Value); }
 
-  /// inverted - Return the opposite value of the current value.
+  /// Returns the opposite value of this ConstantBool value.
+  /// @brief Get inverse value.
   inline ConstantBool *inverted() const { return (this==True) ? False : True; }
 
-  /// getValue - return the boolean value of this constant.
-  ///
+  /// @returns the value of this ConstantBool
+  /// @brief return the boolean value of this constant.
   inline bool getValue() const { return static_cast<bool>(getRawValue()); }
 
-  /// isNullValue - Return true if this is the value that would be returned by
-  /// getNullValue.
-  ///
+  /// @see ConstantIntegral for details
+  /// @brief Implement overrides
   virtual bool isNullValue() const { return this == False; }
   virtual bool isMaxValue() const { return this == True; }
   virtual bool isMinValue() const { return this == False; }
   virtual bool isAllOnesValue() const { return this == True; }
 
-  /// Methods for support type inquiry through isa, cast, and dyn_cast:
+  /// @brief Methods to support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const ConstantBool *) { return true; }
   static bool classof(const Value *V) {
     return V->getValueType() == ConstantBoolVal;
@@ -140,37 +161,36 @@ public:
 
 
 //===----------------------------------------------------------------------===//
-/// ConstantInt - Superclass of ConstantSInt & ConstantUInt, to make dealing
-/// with integral constants easier.
-///
+/// This is the abstract superclass of ConstantSInt & ConstantUInt, to make 
+/// dealing with integral constants easier when sign is irrelevant.
+/// @brief Abstract clas for constant integers.
 class ConstantInt : public ConstantIntegral {
 protected:
   ConstantInt(const ConstantInt &);      // DO NOT IMPLEMENT
   ConstantInt(const Type *Ty, ValueTy VT, uint64_t V);
 public:
-  /// equalsInt - Provide a helper method that can be used to determine if the
-  /// constant contained within is equal to a constant.  This only works for
-  /// very small values, because this is all that can be represented with all
-  /// types.
-  ///
+  /// A helper method that can be used to determine if the constant contained 
+  /// within is equal to a constant.  This only works for very small values, 
+  /// because this is all that can be represented with all types.
+  /// @brief Determine if this constant's value is same as an unsigned char.
   bool equalsInt(unsigned char V) const {
     assert(V <= 127 &&
            "equalsInt: Can only be used with very small positive constants!");
     return Val.Unsigned == V;
   }
 
-  /// ConstantInt::get static method: return a ConstantInt with the specified
-  /// value.  as above, we work only with very small values here.
-  ///
+  /// Return a ConstantInt with the specified value for the specified type. 
+  /// This only works for very small values, because this is all that can be 
+  /// represented with all types integer types.
+  /// @brief Get a ConstantInt for a specific value.
   static ConstantInt *get(const Type *Ty, unsigned char V);
 
-  /// isNullValue - Return true if this is the value that would be returned by
-  /// getNullValue.
+  /// @returns true if this is the null integer value.
+  /// @see ConstantIntegral for details
+  /// @brief Implement override.
   virtual bool isNullValue() const { return Val.Unsigned == 0; }
-  virtual bool isMaxValue() const = 0;
-  virtual bool isMinValue() const = 0;
 
-  /// Methods for support type inquiry through isa, cast, and dyn_cast:
+  /// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
   static inline bool classof(const ConstantInt *) { return true; }
   static bool classof(const Value *V) {
     return V->getValueType() == ConstantSIntVal ||
@@ -180,8 +200,9 @@ public:
 
 
 //===----------------------------------------------------------------------===//
-/// ConstantSInt - Signed Integer Values [sbyte, short, int, long]
-///
+/// A concrete class to represent constant signed integer values for the types
+/// sbyte, short, int, and long.
+/// @brief Constant Signed Integer Class.
 class ConstantSInt : public ConstantInt {
   ConstantSInt(const ConstantSInt &);      // DO NOT IMPLEMENT
   friend struct ConstantCreator<ConstantSInt, Type, int64_t>;
@@ -189,23 +210,35 @@ class ConstantSInt : public ConstantInt {
 protected:
   ConstantSInt(const Type *Ty, int64_t V);
 public:
-  /// get() - Static factory methods - Return objects of the specified value
-  ///
-  static ConstantSInt *get(const Type *Ty, int64_t V);
-
-  /// isValueValidForType - return true if Ty is big enough to represent V.
-  ///
+  /// This static factory methods returns objects of the specified value. Note
+  /// that repeated calls with the same operands return the same object.
+  /// @returns A ConstantSInt instant for the type and value requested.
+  /// @brief Get a signed integer constant.
+  static ConstantSInt *get(
+    const Type *Ty,  ///< The type of constant (SByteTy, IntTy, ShortTy, LongTy)
+    int64_t V        ///< The value for the constant integer.
+  );
+
+  /// This static method returns true if the type Ty is big enough to 
+  /// represent the value V. This can be used to avoid having the get method 
+  /// assert when V is larger than Ty can represent.
+  /// @returns true if V is a valid value for type Ty
+  /// @brief Determine if the value is in range for the given type.
   static bool isValueValidForType(const Type *Ty, int64_t V);
 
-  /// getValue - return the underlying value of this constant.
-  ///
+  /// @returns the underlying value of this constant.
+  /// @brief Get the constant value.
   inline int64_t getValue() const { return Val.Signed; }
 
+  /// @returns true iff this constant's bits are all set to true.
+  /// @see ConstantIntegral
+  /// @brief Override implementation
   virtual bool isAllOnesValue() const { return getValue() == -1; }
 
-  /// isMaxValue - Return true if this is the largest value that may be
-  /// represented by this type.
-  ///
+  /// @returns true iff this is the largest value that may be represented 
+  /// by this type.
+  /// @see ConstantIntegeral
+  /// @brief Override implementation
   virtual bool isMaxValue() const {
     int64_t V = getValue();
     if (V < 0) return false;    // Be careful about wrap-around on 'long's
@@ -213,9 +246,10 @@ public:
     return !isValueValidForType(getType(), V) || V < 0;
   }
 
-  /// isMinValue - Return true if this is the smallest value that may be
-  /// represented by this type.
-  ///
+  /// @returns true if this is the smallest value that may be represented by 
+  /// this type.
+  /// @see ConstantIntegral
+  /// @brief Override implementation
   virtual bool isMinValue() const {
     int64_t V = getValue();
     if (V > 0) return false;    // Be careful about wrap-around on 'long's
@@ -223,8 +257,7 @@ public:
     return !isValueValidForType(getType(), V) || V > 0;
   }
 
-  /// Methods for support type inquiry through isa, cast, and dyn_cast:
-  ///
+  /// @brief Methods to support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const ConstantSInt *) { return true; }
   static bool classof(const Value *V) {
     return V->getValueType() == ConstantSIntVal;
@@ -232,8 +265,9 @@ public:
 };
 
 //===----------------------------------------------------------------------===//
-/// ConstantUInt - Unsigned Integer Values [ubyte, ushort, uint, ulong]
-///
+/// A concrete class that represents constant unsigned integer values of type
+/// Type::UByteTy, Type::UShortTy, Type::UIntTy, or Type::ULongTy.
+/// @brief Constant Unsigned Integer Class
 class ConstantUInt : public ConstantInt {
   ConstantUInt(const ConstantUInt &);      // DO NOT IMPLEMENT
   friend struct ConstantCreator<ConstantUInt, Type, uint64_t>;
diff --git a/lib/Archive/ArchiveReader.cpp b/lib/Archive/ArchiveReader.cpp
index 38aa072..e4769ca 100644
--- a/lib/Archive/ArchiveReader.cpp
+++ b/lib/Archive/ArchiveReader.cpp
@@ -475,14 +475,16 @@ Archive::findModuleDefiningSymbol(const std::string& symbol,
   const char* modptr = base + fileOffset;
   ArchiveMember* mbr = parseMemberHeader(modptr, base + mapfile->size(),ErrMsg);
   if (!mbr)
-    return false;
+    return 0;
 
   // Now, load the bytecode module to get the ModuleProvider
   std::string FullMemberName = archPath.toString() + "(" +
     mbr->getPath().toString() + ")";
   ModuleProvider* mp = getBytecodeBufferModuleProvider(
       (const unsigned char*) mbr->getData(), mbr->getSize(),
-      FullMemberName, 0);
+      FullMemberName, ErrMsg, 0);
+  if (!mp)
+    return 0;
 
   modules.insert(std::make_pair(fileOffset, std::make_pair(mp, mbr)));
 
@@ -523,7 +525,7 @@ Archive::findModulesDefiningSymbols(std::set<std::string>& symbols,
         std::string FullMemberName = archPath.toString() + "(" +
           mbr->getPath().toString() + ")";
         ModuleProvider* MP = GetBytecodeSymbols((const unsigned char*)At,
-            mbr->getSize(), FullMemberName, symbols);
+            mbr->getSize(), FullMemberName, symbols, error);
 
         if (MP) {
           // Insert the module's symbols into the symbol table
@@ -537,7 +539,7 @@ Archive::findModulesDefiningSymbols(std::set<std::string>& symbols,
         } else {
           if (error)
             *error = "Can't parse bytecode member: " + 
-              mbr->getPath().toString();
+              mbr->getPath().toString() + ": " + *error;
           delete mbr;
           return false;
         }
diff --git a/lib/Archive/ArchiveWriter.cpp b/lib/Archive/ArchiveWriter.cpp
index 3746dbf..096a999 100644
--- a/lib/Archive/ArchiveWriter.cpp
+++ b/lib/Archive/ArchiveWriter.cpp
@@ -223,7 +223,7 @@ Archive::writeMember(
       member.getPath().toString()
       + ")";
     ModuleProvider* MP = GetBytecodeSymbols(
-      (const unsigned char*)data,fSize,FullMemberName, symbols);
+      (const unsigned char*)data,fSize,FullMemberName, symbols, ErrMsg);
 
     // If the bytecode parsed successfully
     if ( MP ) {
@@ -247,7 +247,8 @@ Archive::writeMember(
         delete mFile;
       }
       if (ErrMsg)
-        *ErrMsg = "Can't parse bytecode member: " + member.getPath().toString();
+        *ErrMsg = "Can't parse bytecode member: " + member.getPath().toString()
+          + ": " + *ErrMsg;
       return true;
     }
   }
diff --git a/lib/Bytecode/Archive/ArchiveReader.cpp b/lib/Bytecode/Archive/ArchiveReader.cpp
index 38aa072..e4769ca 100644
--- a/lib/Bytecode/Archive/ArchiveReader.cpp
+++ b/lib/Bytecode/Archive/ArchiveReader.cpp
@@ -475,14 +475,16 @@ Archive::findModuleDefiningSymbol(const std::string& symbol,
   const char* modptr = base + fileOffset;
   ArchiveMember* mbr = parseMemberHeader(modptr, base + mapfile->size(),ErrMsg);
   if (!mbr)
-    return false;
+    return 0;
 
   // Now, load the bytecode module to get the ModuleProvider
   std::string FullMemberName = archPath.toString() + "(" +
     mbr->getPath().toString() + ")";
   ModuleProvider* mp = getBytecodeBufferModuleProvider(
       (const unsigned char*) mbr->getData(), mbr->getSize(),
-      FullMemberName, 0);
+      FullMemberName, ErrMsg, 0);
+  if (!mp)
+    return 0;
 
   modules.insert(std::make_pair(fileOffset, std::make_pair(mp, mbr)));
 
@@ -523,7 +525,7 @@ Archive::findModulesDefiningSymbols(std::set<std::string>& symbols,
         std::string FullMemberName = archPath.toString() + "(" +
           mbr->getPath().toString() + ")";
         ModuleProvider* MP = GetBytecodeSymbols((const unsigned char*)At,
-            mbr->getSize(), FullMemberName, symbols);
+            mbr->getSize(), FullMemberName, symbols, error);
 
         if (MP) {
           // Insert the module's symbols into the symbol table
@@ -537,7 +539,7 @@ Archive::findModulesDefiningSymbols(std::set<std::string>& symbols,
         } else {
           if (error)
             *error = "Can't parse bytecode member: " + 
-              mbr->getPath().toString();
+              mbr->getPath().toString() + ": " + *error;
           delete mbr;
           return false;
         }
diff --git a/lib/Bytecode/Archive/ArchiveWriter.cpp b/lib/Bytecode/Archive/ArchiveWriter.cpp
index 3746dbf..096a999 100644
--- a/lib/Bytecode/Archive/ArchiveWriter.cpp
+++ b/lib/Bytecode/Archive/ArchiveWriter.cpp
@@ -223,7 +223,7 @@ Archive::writeMember(
       member.getPath().toString()
       + ")";
     ModuleProvider* MP = GetBytecodeSymbols(
-      (const unsigned char*)data,fSize,FullMemberName, symbols);
+      (const unsigned char*)data,fSize,FullMemberName, symbols, ErrMsg);
 
     // If the bytecode parsed successfully
     if ( MP ) {
@@ -247,7 +247,8 @@ Archive::writeMember(
         delete mFile;
       }
       if (ErrMsg)
-        *ErrMsg = "Can't parse bytecode member: " + member.getPath().toString();
+        *ErrMsg = "Can't parse bytecode member: " + member.getPath().toString()
+          + ": " + *ErrMsg;
       return true;
     }
   }
diff --git a/lib/Bytecode/Reader/ReaderWrappers.cpp b/lib/Bytecode/Reader/ReaderWrappers.cpp
index 1767159..019d7be 100644
--- a/lib/Bytecode/Reader/ReaderWrappers.cpp
+++ b/lib/Bytecode/Reader/ReaderWrappers.cpp
@@ -35,6 +35,7 @@ namespace {
   ///
   class BytecodeFileReader : public BytecodeReader {
   private:
+    std::string fileName;
     sys::MappedFile mapFile;
 
     BytecodeFileReader(const BytecodeFileReader&); // Do not implement
@@ -42,23 +43,30 @@ namespace {
 
   public:
     BytecodeFileReader(const std::string &Filename, llvm::BytecodeHandler* H=0);
+    bool read(std::string* ErrMsg);
   };
 }
 
 BytecodeFileReader::BytecodeFileReader(const std::string &Filename,
                                        llvm::BytecodeHandler* H )
   : BytecodeReader(H)
+  , fileName(Filename)
   , mapFile()
 {
-  std::string ErrMsg;
-  if (mapFile.open(sys::Path(Filename), sys::MappedFile::READ_ACCESS, &ErrMsg))
-    throw ErrMsg;
-  if (!mapFile.map(&ErrMsg))
-    throw ErrMsg;
+}
+
+bool BytecodeFileReader::read(std::string* ErrMsg) {
+  if (mapFile.open(sys::Path(fileName), sys::MappedFile::READ_ACCESS, ErrMsg))
+    return true;
+  if (!mapFile.map(ErrMsg)) {
+    mapFile.close();
+    return true;
+  }
   unsigned char* buffer = reinterpret_cast<unsigned char*>(mapFile.base());
-  if (ParseBytecode(buffer, mapFile.size(), Filename, &ErrMsg)) {
-    throw ErrMsg;
+  if (ParseBytecode(buffer, mapFile.size(), fileName, ErrMsg)) {
+    return true;
   }
+  return false;
 }
 
 //===----------------------------------------------------------------------===//
@@ -71,6 +79,9 @@ namespace {
   class BytecodeBufferReader : public BytecodeReader {
   private:
     const unsigned char *Buffer;
+    const unsigned char *Buf;
+    unsigned Length;
+    std::string ModuleID;
     bool MustDelete;
 
     BytecodeBufferReader(const BytecodeBufferReader&); // Do not implement
@@ -82,15 +93,30 @@ namespace {
                          llvm::BytecodeHandler* Handler = 0);
     ~BytecodeBufferReader();
 
+    bool read(std::string* ErrMsg);
+
   };
 }
 
-BytecodeBufferReader::BytecodeBufferReader(const unsigned char *Buf,
-                                           unsigned Length,
-                                           const std::string &ModuleID,
-                                           llvm::BytecodeHandler* H )
+BytecodeBufferReader::BytecodeBufferReader(const unsigned char *buf,
+                                           unsigned len,
+                                           const std::string &modID,
+                                           llvm::BytecodeHandler* H)
   : BytecodeReader(H)
+  , Buffer(0)
+  , Buf(buf)
+  , Length(len)
+  , ModuleID(modID)
+  , MustDelete(false)
 {
+}
+
+BytecodeBufferReader::~BytecodeBufferReader() {
+  if (MustDelete) delete [] Buffer;
+}
+
+bool
+BytecodeBufferReader::read(std::string* ErrMsg) {
   // If not aligned, allocate a new buffer to hold the bytecode...
   const unsigned char *ParseBegin = 0;
   if (reinterpret_cast<uint64_t>(Buf) & 3) {
@@ -104,15 +130,11 @@ BytecodeBufferReader::BytecodeBufferReader(const unsigned char *Buf,
     ParseBegin = Buffer = Buf;
     MustDelete = false;
   }
-  std::string ErrMsg;
-  if (ParseBytecode(ParseBegin, Length, ModuleID, &ErrMsg)) {
+  if (ParseBytecode(ParseBegin, Length, ModuleID, ErrMsg)) {
     if (MustDelete) delete [] Buffer;
-    throw ErrMsg;
+    return true;
   }
-}
-
-BytecodeBufferReader::~BytecodeBufferReader() {
-  if (MustDelete) delete [] Buffer;
+  return false;
 }
 
 //===----------------------------------------------------------------------===//
@@ -132,12 +154,18 @@ namespace {
 
   public:
     BytecodeStdinReader( llvm::BytecodeHandler* H = 0 );
+    bool read(std::string* ErrMsg);
   };
 }
 
 BytecodeStdinReader::BytecodeStdinReader( BytecodeHandler* H )
   : BytecodeReader(H)
 {
+}
+
+bool
+BytecodeStdinReader::read(std::string* ErrMsg)
+{
   sys::Program::ChangeStdinToBinary();
   char Buffer[4096*4];
 
@@ -150,14 +178,16 @@ BytecodeStdinReader::BytecodeStdinReader( BytecodeHandler* H )
     FileData.insert(FileData.end(), Buffer, Buffer+BlockSize);
   }
 
-  if (FileData.empty())
-    throw std::string("Standard Input empty!");
+  if (FileData.empty()) {
+    if (ErrMsg)
+      *ErrMsg = "Standard Input is empty!";
+    return true;
+  }
 
   FileBuf = &FileData[0];
-  std::string ErrMsg;
-  if (ParseBytecode(FileBuf, FileData.size(), "<stdin>", &ErrMsg)) {
-    throw ErrMsg;
-  }
+  if (ParseBytecode(FileBuf, FileData.size(), "<stdin>", ErrMsg))
+    return true;
+  return false;
 }
 
 //===----------------------------------------------------------------------===//
@@ -270,66 +300,71 @@ ModuleProvider*
 llvm::getBytecodeBufferModuleProvider(const unsigned char *Buffer,
                                       unsigned Length,
                                       const std::string &ModuleID,
-                                      BytecodeHandler* H ) {
-  return CheckVarargs(
-     new BytecodeBufferReader(Buffer, Length, ModuleID, H));
+                                      std::string* ErrMsg, 
+                                      BytecodeHandler* H) {
+  BytecodeBufferReader* rdr = 
+    new BytecodeBufferReader(Buffer, Length, ModuleID, H);
+  if (rdr->read(ErrMsg))
+    return 0;
+  return CheckVarargs(rdr);
 }
 
 /// ParseBytecodeBuffer - Parse a given bytecode buffer
 ///
 Module *llvm::ParseBytecodeBuffer(const unsigned char *Buffer, unsigned Length,
                                   const std::string &ModuleID,
-                                  std::string *ErrorStr){
-  try {
-    std::auto_ptr<ModuleProvider>
-      AMP(getBytecodeBufferModuleProvider(Buffer, Length, ModuleID));
-    return AMP->releaseModule();
-  } catch (std::string &err) {
-    if (ErrorStr) *ErrorStr = err;
+                                  std::string *ErrMsg){
+  ModuleProvider* MP = 
+    getBytecodeBufferModuleProvider(Buffer, Length, ModuleID, ErrMsg, 0);
+  if (!MP)
     return 0;
-  }
+  return MP->releaseModule();
 }
 
 /// getBytecodeModuleProvider - lazy function-at-a-time loading from a file
 ///
-ModuleProvider *llvm::getBytecodeModuleProvider(const std::string &Filename,
-                                                BytecodeHandler* H) {
-  if (Filename != std::string("-"))        // Read from a file...
-    return CheckVarargs(new BytecodeFileReader(Filename,H));
-  else                                     // Read from stdin
-    return CheckVarargs(new BytecodeStdinReader(H));
+ModuleProvider *
+llvm::getBytecodeModuleProvider(const std::string &Filename,
+                                std::string* ErrMsg,
+                                BytecodeHandler* H) {
+  // Read from a file
+  if (Filename != std::string("-")) {
+    BytecodeFileReader* rdr = new BytecodeFileReader(Filename, H);
+    if (rdr->read(ErrMsg))
+      return 0;
+    return CheckVarargs(rdr);
+  }
+
+  // Read from stdin
+  BytecodeStdinReader* rdr = new BytecodeStdinReader(H);
+  if (rdr->read(ErrMsg))
+    return 0;
+  return CheckVarargs(rdr);
 }
 
 /// ParseBytecodeFile - Parse the given bytecode file
 ///
 Module *llvm::ParseBytecodeFile(const std::string &Filename,
-                                std::string *ErrorStr) {
-  try {
-    std::auto_ptr<ModuleProvider> AMP(getBytecodeModuleProvider(Filename));
-    return AMP->releaseModule();
-  } catch (std::string &err) {
-    if (ErrorStr) *ErrorStr = err;
+                                std::string *ErrMsg) {
+  ModuleProvider* MP = getBytecodeModuleProvider(Filename, ErrMsg);
+  if (!MP)
     return 0;
-  }
+  return MP->releaseModule();
 }
 
 // AnalyzeBytecodeFile - analyze one file
 Module* llvm::AnalyzeBytecodeFile(
   const std::string &Filename,  ///< File to analyze
   BytecodeAnalysis& bca,        ///< Statistical output
-  std::string *ErrorStr,        ///< Error output
+  std::string *ErrMsg,          ///< Error output
   std::ostream* output          ///< Dump output
 )
 {
-  try {
-    BytecodeHandler* analyzerHandler =createBytecodeAnalyzerHandler(bca,output);
-    std::auto_ptr<ModuleProvider> AMP(
-      getBytecodeModuleProvider(Filename,analyzerHandler));
-    return AMP->releaseModule();
-  } catch (std::string &err) {
-    if (ErrorStr) *ErrorStr = err;
+  BytecodeHandler* AH = createBytecodeAnalyzerHandler(bca,output);
+  ModuleProvider* MP = getBytecodeModuleProvider(Filename, ErrMsg, AH);
+  if (!MP)
     return 0;
-  }
+  return MP->releaseModule();
 }
 
 // AnalyzeBytecodeBuffer - analyze a buffer
@@ -338,34 +373,30 @@ Module* llvm::AnalyzeBytecodeBuffer(
   unsigned Length,             ///< Size of the bytecode buffer
   const std::string& ModuleID, ///< Identifier for the module
   BytecodeAnalysis& bca,       ///< The results of the analysis
-  std::string* ErrorStr,       ///< Errors, if any.
+  std::string* ErrMsg,         ///< Errors, if any.
   std::ostream* output         ///< Dump output, if any
 )
 {
-  try {
-    BytecodeHandler* hdlr = createBytecodeAnalyzerHandler(bca, output);
-    std::auto_ptr<ModuleProvider>
-      AMP(getBytecodeBufferModuleProvider(Buffer, Length, ModuleID, hdlr));
-    return AMP->releaseModule();
-  } catch (std::string &err) {
-    if (ErrorStr) *ErrorStr = err;
+  BytecodeHandler* hdlr = createBytecodeAnalyzerHandler(bca, output);
+  ModuleProvider* MP = 
+    getBytecodeBufferModuleProvider(Buffer, Length, ModuleID, ErrMsg, hdlr);
+  if (!MP)
     return 0;
-  }
+  return MP->releaseModule();
 }
 
 bool llvm::GetBytecodeDependentLibraries(const std::string &fname,
-                                         Module::LibraryListType& deplibs) {
-  try {
-    std::auto_ptr<ModuleProvider> AMP( getBytecodeModuleProvider(fname));
-    Module* M = AMP->releaseModule();
-
-    deplibs = M->getLibraries();
-    delete M;
-    return true;
-  } catch (...) {
+                                         Module::LibraryListType& deplibs,
+                                         std::string* ErrMsg) {
+  ModuleProvider* MP =  getBytecodeModuleProvider(fname, ErrMsg);
+  if (!MP) {
     deplibs.clear();
-    return false;
+    return true;
   }
+  Module* M = MP->releaseModule();
+  deplibs = M->getLibraries();
+  delete M;
+  return false;
 }
 
 static void getSymbols(Module*M, std::vector<std::string>& symbols) {
@@ -384,13 +415,16 @@ static void getSymbols(Module*M, std::vector<std::string>& symbols) {
 
 // Get just the externally visible defined symbols from the bytecode
 bool llvm::GetBytecodeSymbols(const sys::Path& fName,
-                              std::vector<std::string>& symbols) {
-  std::auto_ptr<ModuleProvider> AMP(
-      getBytecodeModuleProvider(fName.toString()));
+                              std::vector<std::string>& symbols,
+                              std::string* ErrMsg) {
+  ModuleProvider* MP = getBytecodeModuleProvider(fName.toString(), ErrMsg);
+  if (!MP)
+    return true;
 
   // Get the module from the provider
-  Module* M = AMP->materializeModule();
-  if (M == 0) return false;
+  Module* M = MP->materializeModule();
+  if (M == 0) 
+    return true;
 
   // Get the symbols
   getSymbols(M, symbols);
@@ -402,29 +436,26 @@ bool llvm::GetBytecodeSymbols(const sys::Path& fName,
 ModuleProvider*
 llvm::GetBytecodeSymbols(const unsigned char*Buffer, unsigned Length,
                          const std::string& ModuleID,
-                         std::vector<std::string>& symbols) {
-
-  ModuleProvider* MP = 0;
-  try {
-    // Get the module provider
-    MP = getBytecodeBufferModuleProvider(Buffer, Length, ModuleID);
-
-    // Get the module from the provider
-    Module* M = MP->materializeModule();
-    if (M == 0) return 0;
-
-    // Get the symbols
-    getSymbols(M, symbols);
-
-    // Done with the module. Note that ModuleProvider will delete the
-    // Module when it is deleted. Also note that its the caller's responsibility
-    // to delete the ModuleProvider.
-    return MP;
+                         std::vector<std::string>& symbols,
+                         std::string* ErrMsg) {
+  // Get the module provider
+  ModuleProvider* MP = 
+    getBytecodeBufferModuleProvider(Buffer, Length, ModuleID, ErrMsg, 0);
+  if (!MP)
+    return 0;
 
-  } catch (...) {
-    // We delete only the ModuleProvider here because its destructor will
-    // also delete the Module (we used materializeModule not releaseModule).
+  // Get the module from the provider
+  Module* M = MP->materializeModule();
+  if (M == 0) {
     delete MP;
+    return 0;
   }
-  return 0;
+
+  // Get the symbols
+  getSymbols(M, symbols);
+
+  // Done with the module. Note that ModuleProvider will delete the
+  // Module when it is deleted. Also note that its the caller's responsibility
+  // to delete the ModuleProvider.
+  return MP;
 }
diff --git a/lib/Debugger/Debugger.cpp b/lib/Debugger/Debugger.cpp
index a0505bd..613a19d 100644
--- a/lib/Debugger/Debugger.cpp
+++ b/lib/Debugger/Debugger.cpp
@@ -45,15 +45,7 @@ std::string Debugger::getProgramPath() const {
 
 static Module *
 getMaterializedModuleProvider(const std::string &Filename) {
-  try {
-    std::auto_ptr<ModuleProvider> Result(getBytecodeModuleProvider(Filename));
-    if (!Result.get()) return 0;
-
-    Result->materializeModule();
-    return Result.release()->releaseModule();
-  } catch (...) {
-    return 0;
-  }
+  return ParseBytecodeFile(Filename);
 }
 
 /// loadProgram - If a program is currently loaded, unload it.  Then search
diff --git a/tools/lli/lli.cpp b/tools/lli/lli.cpp
index d8f2b16..be9f999 100644
--- a/tools/lli/lli.cpp
+++ b/tools/lli/lli.cpp
@@ -59,11 +59,10 @@ int main(int argc, char **argv, char * const *envp) {
     // Load the bytecode...
     std::string ErrorMsg;
     ModuleProvider *MP = 0;
-    try {
-      MP = getBytecodeModuleProvider(InputFile);
-    } catch (std::string &err) {
+    MP = getBytecodeModuleProvider(InputFile, &ErrorMsg);
+    if (!MP) {
       std::cerr << "Error loading program '" << InputFile << "': "
-                << err << "\n";
+                << ErrorMsg << "\n";
       exit(1);
     }
 
diff --git a/tools/llvmc/CompilerDriver.cpp b/tools/llvmc/CompilerDriver.cpp
index a6aff4e..46dbd89 100644
--- a/tools/llvmc/CompilerDriver.cpp
+++ b/tools/llvmc/CompilerDriver.cpp
@@ -576,7 +576,7 @@ private:
     if (fullpath.isBytecodeFile()) {
       // Process the dependent libraries recursively
       Module::LibraryListType modlibs;
-      if (GetBytecodeDependentLibraries(fullpath.toString(),modlibs)) {
+      if (GetBytecodeDependentLibraries(fullpath.toString(),modlibs,&err)) {
         // Traverse the dependent libraries list
         Module::lib_iterator LI = modlibs.begin();
         Module::lib_iterator LE = modlibs.end();
@@ -598,7 +598,8 @@ private:
           "The dependent libraries could not be extracted from '") +
           fullpath.toString();
         return false;
-      }
+      } else 
+        return false;
     }
     return true;
   }