diff --git a/llvm/include/llvm/Metadata.h b/llvm/include/llvm/Metadata.h
index 1ece55935f94..10433df7d939 100644
--- a/llvm/include/llvm/Metadata.h
+++ b/llvm/include/llvm/Metadata.h
@@ -244,9 +244,9 @@ public:
   /// the same metadata to In2.
   void copyMD(Instruction *In1, Instruction *In2);
 
-  /// getHandlerNames - Populate client supplied smallvector using custom
-  /// metadata name and ID.
-  void getHandlerNames(SmallVectorImpl<std::pair<unsigned, StringRef> >&) const;
+  /// getMDKindNames - Populate client supplied SmallVector with the name for
+  /// each custom metadata ID.   ID #0 is not used, so it is filled in as empty.
+  void getMDKindNames(SmallVectorImpl<StringRef> &) const;
 
   /// ValueIsDeleted - This handler is used to update metadata store
   /// when a value is deleted.
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index ab514d2cb5ba..cf8f7670c72d 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -593,35 +593,30 @@ static void WriteMetadataAttachment(const Function &F,
     Stream.ExitBlock();
 }
 
-static void WriteModuleMetadataStore(const Module *M,
-                                     const ValueEnumerator &VE,
-                                     BitstreamWriter &Stream) {
-
-  bool StartedMetadataBlock = false;
+static void WriteModuleMetadataStore(const Module *M, BitstreamWriter &Stream) {
   SmallVector<uint64_t, 64> Record;
 
   // Write metadata kinds
   // METADATA_KIND - [n x [id, name]]
   MetadataContext &TheMetadata = M->getContext().getMetadata();
-  SmallVector<std::pair<unsigned, StringRef>, 4> Names;
-  TheMetadata.getHandlerNames(Names);
-  for (SmallVector<std::pair<unsigned, StringRef>, 4>::iterator 
-         I = Names.begin(),
-         E = Names.end(); I != E; ++I) {
-    Record.push_back(I->first);
-    StringRef KName = I->second;
-    for (unsigned i = 0, e = KName.size(); i != e; ++i)
-      Record.push_back(KName[i]);
-    if (!StartedMetadataBlock)  {
-      Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
-      StartedMetadataBlock = true;
-    }
+  SmallVector<StringRef, 4> Names;
+  TheMetadata.getMDKindNames(Names);
+  
+  assert(Names[0] == "" && "MDKind #0 is invalid");
+  if (Names.size() == 1) return;
+
+  Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
+  
+  for (unsigned MDKindID = 1, e = Names.size(); MDKindID != e; ++MDKindID) {
+    Record.push_back(MDKindID);
+    StringRef KName = Names[MDKindID];
+    Record.append(KName.begin(), KName.end());
+    
     Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
     Record.clear();
   }
 
-  if (StartedMetadataBlock)
-    Stream.ExitBlock();
+  Stream.ExitBlock();
 }
 
 static void WriteConstants(unsigned FirstVal, unsigned LastVal,
@@ -1466,7 +1461,7 @@ static void WriteModule(const Module *M, BitstreamWriter &Stream) {
       WriteFunction(*I, VE, Stream);
 
   // Emit metadata.
-  WriteModuleMetadataStore(M, VE, Stream);
+  WriteModuleMetadataStore(M, Stream);
 
   // Emit the type symbol table information.
   WriteTypeSymbolTable(M->getTypeSymbolTable(), VE, Stream);
diff --git a/llvm/lib/VMCore/AsmWriter.cpp b/llvm/lib/VMCore/AsmWriter.cpp
index 4ef57fed872f..c9c9bf0fe9e0 100644
--- a/llvm/lib/VMCore/AsmWriter.cpp
+++ b/llvm/lib/VMCore/AsmWriter.cpp
@@ -1330,8 +1330,8 @@ class AssemblyWriter {
   TypePrinting TypePrinter;
   AssemblyAnnotationWriter *AnnotationWriter;
   std::vector<const Type*> NumberedTypes;
-  DenseMap<unsigned, StringRef> MDNames;
-
+  SmallVector<StringRef, 8> MDNames;
+  
 public:
   inline AssemblyWriter(formatted_raw_ostream &o, SlotTracker &Mac,
                         const Module *M,
@@ -1339,16 +1339,8 @@ public:
     : Out(o), Machine(Mac), TheModule(M), AnnotationWriter(AAW) {
     AddModuleTypesToPrinter(TypePrinter, NumberedTypes, M);
     // FIXME: Provide MDPrinter
-    if (M) {
-      MetadataContext &TheMetadata = M->getContext().getMetadata();
-      SmallVector<std::pair<unsigned, StringRef>, 4> Names;
-      TheMetadata.getHandlerNames(Names);
-      for (SmallVector<std::pair<unsigned, StringRef>, 4>::iterator 
-             I = Names.begin(),
-             E = Names.end(); I != E; ++I) {
-      MDNames[I->first] = I->second;
-      }
-    }
+    if (M)
+      M->getContext().getMetadata().getMDKindNames(MDNames);
   }
 
   void write(const Module *M) { printModule(M); }
@@ -2075,14 +2067,14 @@ void AssemblyWriter::printInstruction(const Instruction &I) {
     }
   }
 
-  // Print post operand alignment for load/store
+  // Print post operand alignment for load/store.
   if (isa<LoadInst>(I) && cast<LoadInst>(I).getAlignment()) {
     Out << ", align " << cast<LoadInst>(I).getAlignment();
   } else if (isa<StoreInst>(I) && cast<StoreInst>(I).getAlignment()) {
     Out << ", align " << cast<StoreInst>(I).getAlignment();
   }
 
-  // Print Metadata info
+  // Print Metadata info.
   if (!MDNames.empty()) {
     MetadataContext &TheMetadata = I.getContext().getMetadata();
     typedef SmallVector<std::pair<unsigned, MDNode*>, 2> MDMapTy;
diff --git a/llvm/lib/VMCore/Metadata.cpp b/llvm/lib/VMCore/Metadata.cpp
index 3d136ccf3c40..31e737f41500 100644
--- a/llvm/lib/VMCore/Metadata.cpp
+++ b/llvm/lib/VMCore/Metadata.cpp
@@ -290,9 +290,9 @@ public:
   /// the same metadata to In2.
   void copyMD(Instruction *In1, Instruction *In2);
 
-  /// getHandlerNames - Populate client-supplied smallvector using custom
+  /// getMDKindNames - Populate client-supplied smallvector using custom
   /// metadata name and ID.
-  void getHandlerNames(SmallVectorImpl<std::pair<unsigned, StringRef> >&) const;
+  void getMDKindNames(SmallVectorImpl<StringRef> &) const;
 
   /// ValueIsDeleted - This handler is used to update metadata store
   /// when a value is deleted.
@@ -415,12 +415,13 @@ getMDs(const Instruction *Inst,
 /// getHandlerNames - Populate client supplied smallvector using custome
 /// metadata name and ID.
 void MetadataContextImpl::
-getHandlerNames(SmallVectorImpl<std::pair<unsigned, StringRef> >&Names) const {
-  Names.resize(MDHandlerNames.size());
+getMDKindNames(SmallVectorImpl<StringRef> &Names) const {
+  Names.resize(MDHandlerNames.size()+1);
+  Names[0] = "";
   for (StringMap<unsigned>::const_iterator I = MDHandlerNames.begin(),
          E = MDHandlerNames.end(); I != E; ++I) 
     // MD Handlers are numbered from 1.
-    Names[I->second - 1] = std::make_pair(I->second, I->first());
+    Names[I->second] = I->first();
 }
 
 /// ValueIsCloned - This handler is used to update metadata store
@@ -520,9 +521,8 @@ void MetadataContext::copyMD(Instruction *In1, Instruction *In2) {
 
 /// getHandlerNames - Populate client supplied smallvector using custome
 /// metadata name and ID.
-void MetadataContext::
-getHandlerNames(SmallVectorImpl<std::pair<unsigned, StringRef> >&N) const {
-  pImpl->getHandlerNames(N);
+void MetadataContext::getMDKindNames(SmallVectorImpl<StringRef> &N) const {
+  pImpl->getMDKindNames(N);
 }
 
 /// ValueIsDeleted - This handler is used to update metadata store