Final step in the metadata API restructuring: move the

getMDKindID/getMDKindNames methods to LLVMContext (and add
convenience methods to Module), eliminating MetadataContext.
Move the state that it maintains out to LLVMContext.

llvm-svn: 92259

llvm/include/llvm/Instruction.h

@@ -22,7 +22,6 @@ namespace llvm {
 
 class LLVMContext;
 class MDNode;
-class MetadataContextImpl;
 
 template<typename ValueSubClass, typename ItemParentClass>
   class SymbolTableListTraits;
@@ -316,7 +315,6 @@ private:
     return Value::getSubclassDataFromValue();
   }
   
-  friend class MetadataContextImpl;
   void setHasMetadata(bool V) {
     setValueSubclassData((getSubclassDataFromValue() & ~HasMetadataBit) |
                          (V ? HasMetadataBit : 0));

llvm/include/llvm/LLVMContext.h

@@ -18,7 +18,8 @@
 namespace llvm {
 
 class LLVMContextImpl;
-class MetadataContext;
+class StringRef;
+template <typename T> class SmallVectorImpl;
 
 /// This is an important class for using LLVM in a threaded context.  It
 /// (opaquely) owns and manages the core "global" data of LLVM's core 
@@ -31,14 +32,23 @@ class LLVMContext {
   void operator=(LLVMContext&);
 
 public:
-  LLVMContextImpl* const pImpl;
+  LLVMContextImpl *const pImpl;
-  MetadataContext &getMetadata();
   LLVMContext();
   ~LLVMContext();
+  
+  /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
+  /// This ID is uniqued across modules in the current LLVMContext.
+  unsigned getMDKindID(StringRef Name) const;
+  
+  /// getMDKindNames - Populate client supplied SmallVector with the name for
+  /// custom metadata IDs registered in this LLVMContext.   ID #0 is not used,
+  /// so it is filled in as an empty string.
+  void getMDKindNames(SmallVectorImpl<StringRef> &Result) const;
 };
 
-/// FOR BACKWARDS COMPATIBILITY - Returns a global context.
+/// getGlobalContext - Returns a global context.  This is for LLVM clients that
-extern LLVMContext& getGlobalContext();
+/// only care about operating on a single thread.
+extern LLVMContext &getGlobalContext();
 
 }
 

llvm/include/llvm/Metadata.h

@@ -25,7 +25,6 @@ class Constant;
 class Instruction;
 class LLVMContext;
 class Module;
-class MetadataContextImpl;
 template <typename T> class SmallVectorImpl;
 
 //===----------------------------------------------------------------------===//
@@ -204,28 +203,6 @@ public:
   }
 };
 
-//===----------------------------------------------------------------------===//
-/// MetadataContext - MetadataContext handles uniquing and assignment of IDs for
-/// custom metadata types.
-///
-class MetadataContext {
-  MetadataContext(MetadataContext&); // DO NOT IMPLEMENT
-  void operator=(MetadataContext&);  // DO NOT IMPLEMENT
-
-  MetadataContextImpl *const pImpl;
-  friend class Instruction;
-public:
-  MetadataContext();
-  ~MetadataContext();
-
-  /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
-  unsigned getMDKindID(StringRef Name) 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;
-};
-
 } // end llvm namespace
 
 #endif

llvm/include/llvm/Module.h

@@ -184,7 +184,7 @@ public:
 
   /// Get the global data context.
   /// @returns LLVMContext - a container for LLVM's global information
-  LLVMContext& getContext() const { return Context; }
+  LLVMContext &getContext() const { return Context; }
 
   /// Get any module-scope inline assembly blocks.
   /// @returns a string containing the module-scope inline assembly blocks.
@@ -222,6 +222,15 @@ public:
   /// if a global with the specified name is not found.
   GlobalValue *getNamedValue(StringRef Name) const;
 
+  /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
+  /// This ID is uniqued across modules in the current LLVMContext.
+  unsigned getMDKindID(StringRef Name) const;
+  
+  /// getMDKindNames - Populate client supplied SmallVector with the name for
+  /// custom metadata IDs registered in this LLVMContext.   ID #0 is not used,
+  /// so it is filled in as an empty string.
+  void getMDKindNames(SmallVectorImpl<StringRef> &Result) const;
+  
 /// @}
 /// @name Function Accessors
 /// @{

llvm/include/llvm/Value.h

@@ -41,7 +41,6 @@ class raw_ostream;
 class AssemblyAnnotationWriter;
 class ValueHandleBase;
 class LLVMContext;
-class MetadataContextImpl;
 class Twine;
 
 //===----------------------------------------------------------------------===//

llvm/lib/Analysis/DebugInfo.cpp

@@ -18,7 +18,6 @@
 #include "llvm/Intrinsics.h"
 #include "llvm/IntrinsicInst.h"
 #include "llvm/Instructions.h"
-#include "llvm/LLVMContext.h"
 #include "llvm/Module.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/ADT/SmallPtrSet.h"
@@ -1117,7 +1116,7 @@ Instruction *DIFactory::InsertDbgValueIntrinsic(Value *V, Value *Offset,
 
 /// processModule - Process entire module and collect debug info.
 void DebugInfoFinder::processModule(Module &M) {
-  unsigned MDDbgKind = M.getContext().getMetadata().getMDKindID("dbg");
+  unsigned MDDbgKind = M.getMDKindID("dbg");
 
   for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
     for (Function::iterator FI = (*I).begin(), FE = (*I).end(); FI != FE; ++FI)

llvm/lib/AsmParser/LLParser.cpp

@@ -18,8 +18,6 @@
 #include "llvm/DerivedTypes.h"
 #include "llvm/InlineAsm.h"
 #include "llvm/Instructions.h"
-#include "llvm/LLVMContext.h"
-#include "llvm/Metadata.h"
 #include "llvm/Module.h"
 #include "llvm/Operator.h"
 #include "llvm/ValueSymbolTable.h"
@@ -1122,8 +1120,7 @@ bool LLParser::ParseOptionalCustomMetadata() {
   MetadataBase *Node;
   if (ParseMDNode(Node)) return true;
 
-  MetadataContext &TheMetadata = M->getContext().getMetadata();
+  unsigned MDK = M->getMDKindID(Name.c_str());
-  unsigned MDK = TheMetadata.getMDKindID(Name.c_str());
   MDsOnInst.push_back(std::make_pair(MDK, cast<MDNode>(Node)));
   return false;
 }

llvm/lib/Bitcode/Reader/BitcodeReader.cpp

@@ -17,7 +17,6 @@
 #include "llvm/DerivedTypes.h"
 #include "llvm/InlineAsm.h"
 #include "llvm/IntrinsicInst.h"
-#include "llvm/LLVMContext.h"
 #include "llvm/Module.h"
 #include "llvm/Operator.h"
 #include "llvm/AutoUpgrade.h"
@@ -840,7 +839,7 @@ bool BitcodeReader::ParseMetadata() {
       for (unsigned i = 1; i != RecordLength; ++i)
         Name[i-1] = Record[i];
       
-      unsigned NewKind = Context.getMetadata().getMDKindID(Name.str());
+      unsigned NewKind = TheModule->getMDKindID(Name.str());
       assert(Kind == NewKind &&
              "FIXME: Unable to handle custom metadata mismatch!");(void)NewKind;
       break;

llvm/lib/Bitcode/Reader/BitcodeReader.h

@@ -170,7 +170,7 @@ class BitcodeReader : public ModuleProvider {
   DenseMap<Function*, std::vector<BlockAddrRefTy> > BlockAddrFwdRefs;
   
 public:
-  explicit BitcodeReader(MemoryBuffer *buffer, LLVMContext& C)
+  explicit BitcodeReader(MemoryBuffer *buffer, LLVMContext &C)
     : Context(C), Buffer(buffer), ErrorString(0), ValueList(C), MDValueList(C) {
     HasReversedFunctionsWithBodies = false;
   }

llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -19,8 +19,6 @@
 #include "llvm/DerivedTypes.h"
 #include "llvm/InlineAsm.h"
 #include "llvm/Instructions.h"
-#include "llvm/LLVMContext.h"
-#include "llvm/Metadata.h"
 #include "llvm/Module.h"
 #include "llvm/Operator.h"
 #include "llvm/TypeSymbolTable.h"
@@ -595,9 +593,8 @@ static void WriteModuleMetadataStore(const Module *M, BitstreamWriter &Stream) {
 
   // Write metadata kinds
   // METADATA_KIND - [n x [id, name]]
-  MetadataContext &TheMetadata = M->getContext().getMetadata();
   SmallVector<StringRef, 4> Names;
-  TheMetadata.getMDKindNames(Names);
+  M->getMDKindNames(Names);
   
   assert(Names[0] == "" && "MDKind #0 is invalid");
   if (Names.size() == 1) return;

llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp

@@ -395,8 +395,7 @@ void SelectionDAGISel::SelectBasicBlock(BasicBlock *LLVMBB,
                                         BasicBlock::iterator End,
                                         bool &HadTailCall) {
   SDB->setCurrentBasicBlock(BB);
-  MetadataContext &TheMetadata =LLVMBB->getParent()->getContext().getMetadata();
+  unsigned MDDbgKind = LLVMBB->getContext().getMDKindID("dbg");
-  unsigned MDDbgKind = TheMetadata.getMDKindID("dbg");
 
   // Lower all of the non-terminator instructions. If a call is emitted
   // as a tail call, cease emitting nodes for this block.
@@ -676,8 +675,7 @@ void SelectionDAGISel::SelectAllBasicBlocks(Function &Fn,
 #endif
                                 );
 
-  MetadataContext &TheMetadata = Fn.getContext().getMetadata();
+  unsigned MDDbgKind = Fn.getContext().getMDKindID("dbg");
-  unsigned MDDbgKind = TheMetadata.getMDKindID("dbg");
 
   // Iterate over all basic blocks in the function.
   for (Function::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I) {

llvm/lib/Transforms/IPO/StripSymbols.cpp

@@ -24,7 +24,6 @@
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Instructions.h"
-#include "llvm/LLVMContext.h"
 #include "llvm/Module.h"
 #include "llvm/Pass.h"
 #include "llvm/Analysis/DebugInfo.h"
@@ -220,9 +219,8 @@ static bool StripDebugInfo(Module &M) {
     Changed = true;
     NMD->eraseFromParent();
   }
-  MetadataContext &TheMetadata = M.getContext().getMetadata();
-  unsigned MDDbgKind = TheMetadata.getMDKindID("dbg");
   
+  unsigned MDDbgKind = M.getMDKindID("dbg");
   for (Module::iterator MI = M.begin(), ME = M.end(); MI != ME; ++MI) 
     for (Function::iterator FI = MI->begin(), FE = MI->end(); FI != FE;
          ++FI)

llvm/lib/Transforms/Utils/CloneFunction.cpp

@@ -420,8 +420,7 @@ void llvm::CloneAndPruneFunctionInto(Function *NewFunc, const Function *OldFunc,
     //
     BasicBlock::iterator I = NewBB->begin();
 
-    // FIXME: Only use of context.
+    unsigned DbgKind = OldFunc->getContext().getMDKindID("dbg");
-    unsigned DbgKind = OldFunc->getContext().getMetadata().getMDKindID("dbg");
     MDNode *TheCallMD = NULL;
     SmallVector<Value *, 4> MDVs;
     if (TheCall && TheCall->hasMetadata()) 

llvm/lib/VMCore/AsmWriter.cpp

@@ -22,7 +22,6 @@
 #include "llvm/DerivedTypes.h"
 #include "llvm/InlineAsm.h"
 #include "llvm/IntrinsicInst.h"
-#include "llvm/LLVMContext.h"
 #include "llvm/Operator.h"
 #include "llvm/Module.h"
 #include "llvm/ValueSymbolTable.h"
@@ -1338,7 +1337,7 @@ public:
     AddModuleTypesToPrinter(TypePrinter, NumberedTypes, M);
     // FIXME: Provide MDPrinter
     if (M)
-      M->getContext().getMetadata().getMDKindNames(MDNames);
+      M->getMDKindNames(MDNames);
   }
 
   void write(const Module *M) { printModule(M); }

llvm/lib/VMCore/IRBuilder.cpp

@@ -15,7 +15,6 @@
 #include "llvm/Support/IRBuilder.h"
 #include "llvm/GlobalVariable.h"
 #include "llvm/Function.h"
-#include "llvm/Metadata.h"
 #include "llvm/LLVMContext.h"
 using namespace llvm;
 
@@ -37,7 +36,7 @@ Value *IRBuilderBase::CreateGlobalString(const char *Str, const Twine &Name) {
 /// information.
 void IRBuilderBase::SetCurrentDebugLocation(MDNode *L) {
   if (DbgMDKind == 0) 
-    DbgMDKind = Context.getMetadata().getMDKindID("dbg");
+    DbgMDKind = Context.getMDKindID("dbg");
   CurDbgLocation = L;
 }
 

llvm/lib/VMCore/LLVMContext.cpp

@@ -17,9 +17,7 @@
 #include "llvm/Constants.h"
 #include "llvm/Instruction.h"
 #include "llvm/Support/ManagedStatic.h"
-#include "llvm/Support/ValueHandle.h"
 #include "LLVMContextImpl.h"
-
 using namespace llvm;
 
 static ManagedStatic<LLVMContext> GlobalContext;
@@ -44,6 +42,3 @@ GetElementPtrConstantExpr::GetElementPtrConstantExpr
     OperandList[i+1] = IdxList[i];
 }
 
-MetadataContext &LLVMContext::getMetadata() {
-  return pImpl->TheMetadata;
-}

llvm/lib/VMCore/LLVMContextImpl.h

@@ -23,6 +23,7 @@
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Assembly/Writer.h"
+#include "llvm/Support/ValueHandle.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/APInt.h"
 #include "llvm/ADT/DenseMap.h"
@@ -171,7 +172,17 @@ public:
   typedef DenseMap<Value*, ValueHandleBase*> ValueHandlesTy;
   ValueHandlesTy ValueHandles;
   
-  MetadataContext TheMetadata;
+  /// CustomMDKindNames - Map to hold the metadata string to ID mapping.
+  StringMap<unsigned> CustomMDKindNames;
+  
+  typedef std::pair<unsigned, TrackingVH<MDNode> > MDPairTy;
+  typedef SmallVector<MDPairTy, 2> MDMapTy;
+
+  /// MetadataStore - Collection of per-instruction metadata used in this
+  /// context.
+  DenseMap<const Instruction *, MDMapTy> MetadataStore;
+  
+  
   LLVMContextImpl(LLVMContext &C) : TheTrueVal(0), TheFalseVal(0),
     VoidTy(C, Type::VoidTyID),
     LabelTy(C, Type::LabelTyID),
@@ -187,8 +198,7 @@ public:
     Int32Ty(C, 32),
     Int64Ty(C, 64) { }
 
-  ~LLVMContextImpl()
+  ~LLVMContextImpl() {
-  {
     ExprConstants.freeConstants();
     ArrayConstants.freeConstants();
     StructConstants.freeConstants();

llvm/lib/VMCore/Metadata.cpp

@@ -242,152 +242,9 @@ void NamedMDNode::dropAllReferences() {
 }
 
 
-//===----------------------------------------------------------------------===//
-// MetadataContextImpl implementation.
-//
-namespace llvm {
-class MetadataContextImpl {
-public:
-  typedef std::pair<unsigned, TrackingVH<MDNode> > MDPairTy;
-  typedef SmallVector<MDPairTy, 2> MDMapTy;
-  typedef DenseMap<const Instruction *, MDMapTy> MDStoreTy;
-  friend class BitcodeReader;
-private:
-
-  /// MetadataStore - Collection of metadata used in this context.
-  MDStoreTy MetadataStore;
-
-  /// MDHandlerNames - Map to hold metadata handler names.
-  StringMap<unsigned> MDHandlerNames;
-
-public:
-  // Name <-> ID mapping methods.
-  unsigned getMDKindID(StringRef Name);
-  void getMDKindNames(SmallVectorImpl<StringRef> &) const;
-  
-  
-  // Instruction metadata methods.
-  MDNode *getMetadata(const Instruction *Inst, unsigned Kind);
-  void getAllMetadata(const Instruction *Inst,
-                      SmallVectorImpl<std::pair<unsigned, MDNode*> > &MDs)const;
-
-  void setMetadata(Instruction *Inst, unsigned Kind, MDNode *Node);
-
-  /// removeAllMetadata - Remove all metadata attached to an instruction.
-  void removeAllMetadata(Instruction *Inst);
-};
-}
-
-/// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
-unsigned MetadataContextImpl::getMDKindID(StringRef Name) {
-  unsigned &Entry = MDHandlerNames[Name];
-
-  // If this is new, assign it its ID.
-  if (Entry == 0) Entry = MDHandlerNames.size();
-  return Entry;
-}
-
-/// getHandlerNames - Populate client supplied smallvector using custome
-/// metadata name and ID.
-void MetadataContextImpl::
-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] = I->first();
-}
-
-
-/// getMetadata - Get the metadata of given kind attached to an Instruction.
-/// If the metadata is not found then return 0.
-MDNode *MetadataContextImpl::
-getMetadata(const Instruction *Inst, unsigned MDKind) {
-  MDMapTy &Info = MetadataStore[Inst];
-  assert(Inst->hasMetadata() && !Info.empty() && "Shouldn't have called this");
-  
-  for (MDMapTy::iterator I = Info.begin(), E = Info.end(); I != E; ++I)
-    if (I->first == MDKind)
-      return I->second;
-  return 0;
-}
-
-/// getAllMetadata - Get all of the metadata attached to an Instruction.
-void MetadataContextImpl::
-getAllMetadata(const Instruction *Inst,
-               SmallVectorImpl<std::pair<unsigned, MDNode*> > &Result) const {
-  assert(Inst->hasMetadata() && MetadataStore.find(Inst) != MetadataStore.end()
-         && "Shouldn't have called this");
-  const MDMapTy &Info = MetadataStore.find(Inst)->second;
-  assert(!Info.empty() && "Shouldn't have called this");
-
-  Result.clear();
-  Result.append(Info.begin(), Info.end());
-  
-  // Sort the resulting array so it is stable.
-  if (Result.size() > 1)
-    array_pod_sort(Result.begin(), Result.end());
-}
-
-
-void MetadataContextImpl::setMetadata(Instruction *Inst, unsigned Kind,
-                                      MDNode *Node) {
-  // Handle the case when we're adding/updating metadata on an instruction.
-  if (Node) {
-    MDMapTy &Info = MetadataStore[Inst];
-    assert(!Info.empty() == Inst->hasMetadata() && "HasMetadata bit is wonked");
-    if (Info.empty()) {
-      Inst->setHasMetadata(true);
-    } else {
-      // Handle replacement of an existing value.
-      for (unsigned i = 0, e = Info.size(); i != e; ++i)
-        if (Info[i].first == Kind) {
-          Info[i].second = Node;
-          return;
-        }
-    }
-    
-    // No replacement, just add it to the list.
-    Info.push_back(std::make_pair(Kind, Node));
-    return;
-  }
-  
-  // Otherwise, we're removing metadata from an instruction.
-  assert(Inst->hasMetadata() && MetadataStore.count(Inst) &&
-         "HasMetadata bit out of date!");
-  MDMapTy &Info = MetadataStore[Inst];
-
-  // Common case is removing the only entry.
-  if (Info.size() == 1 && Info[0].first == Kind) {
-    MetadataStore.erase(Inst);
-    Inst->setHasMetadata(false);
-    return;
-  }
-  
-  // Handle replacement of an existing value.
-  for (unsigned i = 0, e = Info.size(); i != e; ++i)
-    if (Info[i].first == Kind) {
-      Info[i] = Info.back();
-      Info.pop_back();
-      assert(!Info.empty() && "Removing last entry should be handled above");
-      return;
-    }
-  // Otherwise, removing an entry that doesn't exist on the instruction.
-}
-
-/// removeAllMetadata - Remove all metadata attached with an instruction.
-void MetadataContextImpl::removeAllMetadata(Instruction *Inst) {
-  MetadataStore.erase(Inst);
-  Inst->setHasMetadata(false);
-}
-
-
 //===----------------------------------------------------------------------===//
 // MetadataContext implementation.
 //
-MetadataContext::MetadataContext() : pImpl(new MetadataContextImpl()) { }
-MetadataContext::~MetadataContext() { delete pImpl; }
 
 #ifndef NDEBUG
 /// isValidName - Return true if Name is a valid custom metadata handler name.
@@ -408,15 +265,25 @@ static bool isValidName(StringRef MDName) {
 #endif
 
 /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
-unsigned MetadataContext::getMDKindID(StringRef Name) const {
+unsigned LLVMContext::getMDKindID(StringRef Name) const {
   assert(isValidName(Name) && "Invalid MDNode name");
-  return pImpl->getMDKindID(Name);
+  
+  unsigned &Entry = pImpl->CustomMDKindNames[Name];
+  
+  // If this is new, assign it its ID.
+  if (Entry == 0) Entry = pImpl->CustomMDKindNames.size();
+  return Entry;
 }
 
 /// getHandlerNames - Populate client supplied smallvector using custome
 /// metadata name and ID.
-void MetadataContext::getMDKindNames(SmallVectorImpl<StringRef> &N) const {
+void LLVMContext::getMDKindNames(SmallVectorImpl<StringRef> &Names) const {
-  pImpl->getMDKindNames(N);
+  Names.resize(pImpl->CustomMDKindNames.size()+1);
+  Names[0] = "";
+  for (StringMap<unsigned>::const_iterator I = pImpl->CustomMDKindNames.begin(),
+       E = pImpl->CustomMDKindNames.end(); I != E; ++I) 
+    // MD Handlers are numbered from 1.
+    Names[I->second] = I->first();
 }
 
 //===----------------------------------------------------------------------===//
@@ -425,11 +292,11 @@ void MetadataContext::getMDKindNames(SmallVectorImpl<StringRef> &N) const {
 
 void Instruction::setMetadata(const char *Kind, MDNode *Node) {
   if (Node == 0 && !hasMetadata()) return;
-  setMetadata(getContext().getMetadata().getMDKindID(Kind), Node);
+  setMetadata(getContext().getMDKindID(Kind), Node);
 }
 
 MDNode *Instruction::getMetadataImpl(const char *Kind) const {
-  return getMetadataImpl(getContext().getMetadata().getMDKindID(Kind));
+  return getMetadataImpl(getContext().getMDKindID(Kind));
 }
 
 /// setMetadata - Set the metadata of of the specified kind to the specified
@@ -438,21 +305,80 @@ MDNode *Instruction::getMetadataImpl(const char *Kind) const {
 void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
   if (Node == 0 && !hasMetadata()) return;
   
-  getContext().getMetadata().pImpl->setMetadata(this, KindID, Node);
+  // Handle the case when we're adding/updating metadata on an instruction.
+  if (Node) {
+    LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
+    assert(!Info.empty() == hasMetadata() && "HasMetadata bit is wonked");
+    if (Info.empty()) {
+      setHasMetadata(true);
+    } else {
+      // Handle replacement of an existing value.
+      for (unsigned i = 0, e = Info.size(); i != e; ++i)
+        if (Info[i].first == KindID) {
+          Info[i].second = Node;
+          return;
+        }
+    }
+    
+    // No replacement, just add it to the list.
+    Info.push_back(std::make_pair(KindID, Node));
+    return;
+  }
+  
+  // Otherwise, we're removing metadata from an instruction.
+  assert(hasMetadata() && getContext().pImpl->MetadataStore.count(this) &&
+         "HasMetadata bit out of date!");
+  LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
+  
+  // Common case is removing the only entry.
+  if (Info.size() == 1 && Info[0].first == KindID) {
+    getContext().pImpl->MetadataStore.erase(this);
+    setHasMetadata(false);
+    return;
+  }
+  
+  // Handle replacement of an existing value.
+  for (unsigned i = 0, e = Info.size(); i != e; ++i)
+    if (Info[i].first == KindID) {
+      Info[i] = Info.back();
+      Info.pop_back();
+      assert(!Info.empty() && "Removing last entry should be handled above");
+      return;
+    }
+  // Otherwise, removing an entry that doesn't exist on the instruction.
 }
 
 MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
-  return getContext().getMetadata().pImpl->getMetadata(this, KindID);
+  LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
+  assert(hasMetadata() && !Info.empty() && "Shouldn't have called this");
+  
+  for (LLVMContextImpl::MDMapTy::iterator I = Info.begin(), E = Info.end();
+       I != E; ++I)
+    if (I->first == KindID)
+      return I->second;
+  return 0;
 }
 
 void Instruction::getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,
                                        MDNode*> > &Result)const {
-  getContext().getMetadata().pImpl->getAllMetadata(this, Result);
+  assert(hasMetadata() && getContext().pImpl->MetadataStore.count(this) &&
+         "Shouldn't have called this");
+  const LLVMContextImpl::MDMapTy &Info =
+    getContext().pImpl->MetadataStore.find(this)->second;
+  assert(!Info.empty() && "Shouldn't have called this");
+  
+  Result.clear();
+  Result.append(Info.begin(), Info.end());
+  
+  // Sort the resulting array so it is stable.
+  if (Result.size() > 1)
+    array_pod_sort(Result.begin(), Result.end());
 }
 
 /// removeAllMetadata - Remove all metadata from this instruction.
 void Instruction::removeAllMetadata() {
   assert(hasMetadata() && "Caller should check");
-  getContext().getMetadata().pImpl->removeAllMetadata(this);
+  getContext().pImpl->MetadataStore.erase(this);
+  setHasMetadata(false);
 }
 

llvm/lib/VMCore/Module.cpp

@@ -118,6 +118,20 @@ GlobalValue *Module::getNamedValue(StringRef Name) const {
   return cast_or_null<GlobalValue>(getValueSymbolTable().lookup(Name));
 }
 
+/// getMDKindID - Return a unique non-zero ID for the specified metadata kind.
+/// This ID is uniqued across modules in the current LLVMContext.
+unsigned Module::getMDKindID(StringRef Name) const {
+  return Context.getMDKindID(Name);
+}
+
+/// getMDKindNames - Populate client supplied SmallVector with the name for
+/// custom metadata IDs registered in this LLVMContext.   ID #0 is not used,
+/// so it is filled in as an empty string.
+void Module::getMDKindNames(SmallVectorImpl<StringRef> &Result) const {
+  return Context.getMDKindNames(Result);
+}
+
+
 //===----------------------------------------------------------------------===//
 // Methods for easy access to the functions in the module.
 //