Revert "IR: MDNode => Value"

Instead, we're going to separate metadata from the Value hierarchy.  See
PR21532.

This reverts commit r221375.
This reverts commit r221373.
This reverts commit r221359.
This reverts commit r221167.
This reverts commit r221027.
This reverts commit r221024.
This reverts commit r221023.
This reverts commit r220995.
This reverts commit r220994.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221711 91177308-0d34-0410-b5e6-96231b3b80d8

42 files changed, 153 insertions, 158 deletions

diff --git a/lib/Analysis/BranchProbabilityInfo.cpp b/lib/Analysis/BranchProbabilityInfo.cpp
index 4e083d2f877..bbd87505952 100644
--- a/lib/Analysis/BranchProbabilityInfo.cpp
+++ b/lib/Analysis/BranchProbabilityInfo.cpp
@@ -180,7 +180,7 @@ bool BranchProbabilityInfo::calcMetadataWeights(BasicBlock *BB) {
   if (!isa<BranchInst>(TI) && !isa<SwitchInst>(TI))
     return false;
 
-  MDNode *WeightsNode = TI->getMDNode(LLVMContext::MD_prof);
+  MDNode *WeightsNode = TI->getMetadata(LLVMContext::MD_prof);
   if (!WeightsNode)
     return false;
 
diff --git a/lib/Analysis/LoopInfo.cpp b/lib/Analysis/LoopInfo.cpp
index fd4382902bf..b1f62c43732 100644
--- a/lib/Analysis/LoopInfo.cpp
+++ b/lib/Analysis/LoopInfo.cpp
@@ -235,7 +235,7 @@ bool Loop::isSafeToClone() const {
 MDNode *Loop::getLoopID() const {
   MDNode *LoopID = nullptr;
   if (isLoopSimplifyForm()) {
-    LoopID = getLoopLatch()->getTerminator()->getMDNode(LoopMDName);
+    LoopID = getLoopLatch()->getTerminator()->getMetadata(LoopMDName);
   } else {
     // Go through each predecessor of the loop header and check the
     // terminator for the metadata.
@@ -247,7 +247,7 @@ MDNode *Loop::getLoopID() const {
       // Check if this terminator branches to the loop header.
       for (unsigned i = 0, ie = TI->getNumSuccessors(); i != ie; ++i) {
         if (TI->getSuccessor(i) == H) {
-          MD = TI->getMDNode(LoopMDName);
+          MD = TI->getMetadata(LoopMDName);
           break;
         }
       }
@@ -309,7 +309,7 @@ bool Loop::isAnnotatedParallel() const {
       // nested parallel loops). The loop identifier metadata refers to
       // itself so we can check both cases with the same routine.
       MDNode *loopIdMD =
-          II->getMDNode(LLVMContext::MD_mem_parallel_loop_access);
+          II->getMetadata(LLVMContext::MD_mem_parallel_loop_access);
 
       if (!loopIdMD)
         return false;
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index a47568e0c7f..7324344c3e0 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -3668,7 +3668,7 @@ ScalarEvolution::GetMinTrailingZeros(const SCEV *S) {
 /// metadata present in the IR.
 static Optional<ConstantRange> GetRangeFromMetadata(Value *V) {
   if (Instruction *I = dyn_cast<Instruction>(V)) {
-    if (MDNode *MD = I->getMDNode(LLVMContext::MD_range)) {
+    if (MDNode *MD = I->getMetadata(LLVMContext::MD_range)) {
       ConstantRange TotalRange(
           cast<IntegerType>(I->getType())->getBitWidth(), false);
 
diff --git a/lib/Analysis/ScopedNoAliasAA.cpp b/lib/Analysis/ScopedNoAliasAA.cpp
index 0c341d9ee4f..f6c300aa0e2 100644
--- a/lib/Analysis/ScopedNoAliasAA.cpp
+++ b/lib/Analysis/ScopedNoAliasAA.cpp
@@ -213,12 +213,12 @@ ScopedNoAliasAA::getModRefInfo(ImmutableCallSite CS, const Location &Loc) {
   if (!EnableScopedNoAlias)
     return AliasAnalysis::getModRefInfo(CS, Loc);
 
-  if (!mayAliasInScopes(Loc.AATags.Scope, CS.getInstruction()->getMDNode(
+  if (!mayAliasInScopes(Loc.AATags.Scope, CS.getInstruction()->getMetadata(
                                               LLVMContext::MD_noalias)))
     return NoModRef;
 
   if (!mayAliasInScopes(
-          CS.getInstruction()->getMDNode(LLVMContext::MD_alias_scope),
+          CS.getInstruction()->getMetadata(LLVMContext::MD_alias_scope),
           Loc.AATags.NoAlias))
     return NoModRef;
 
@@ -231,13 +231,13 @@ ScopedNoAliasAA::getModRefInfo(ImmutableCallSite CS1, ImmutableCallSite CS2) {
     return AliasAnalysis::getModRefInfo(CS1, CS2);
 
   if (!mayAliasInScopes(
-          CS1.getInstruction()->getMDNode(LLVMContext::MD_alias_scope),
-          CS2.getInstruction()->getMDNode(LLVMContext::MD_noalias)))
+          CS1.getInstruction()->getMetadata(LLVMContext::MD_alias_scope),
+          CS2.getInstruction()->getMetadata(LLVMContext::MD_noalias)))
     return NoModRef;
 
   if (!mayAliasInScopes(
-          CS2.getInstruction()->getMDNode(LLVMContext::MD_alias_scope),
-          CS1.getInstruction()->getMDNode(LLVMContext::MD_noalias)))
+          CS2.getInstruction()->getMetadata(LLVMContext::MD_alias_scope),
+          CS1.getInstruction()->getMetadata(LLVMContext::MD_noalias)))
     return NoModRef;
 
   return AliasAnalysis::getModRefInfo(CS1, CS2);
diff --git a/lib/Analysis/TypeBasedAliasAnalysis.cpp b/lib/Analysis/TypeBasedAliasAnalysis.cpp
index 1f288b1a328..f347eb5f191 100644
--- a/lib/Analysis/TypeBasedAliasAnalysis.cpp
+++ b/lib/Analysis/TypeBasedAliasAnalysis.cpp
@@ -493,7 +493,7 @@ TypeBasedAliasAnalysis::getModRefBehavior(ImmutableCallSite CS) {
 
   // If this is an "immutable" type, we can assume the call doesn't write
   // to memory.
-  if (const MDNode *M = CS.getInstruction()->getMDNode(LLVMContext::MD_tbaa))
+  if (const MDNode *M = CS.getInstruction()->getMetadata(LLVMContext::MD_tbaa))
     if ((!isStructPathTBAA(M) && TBAANode(M).TypeIsImmutable()) ||
         (isStructPathTBAA(M) && TBAAStructTagNode(M).TypeIsImmutable()))
       Min = OnlyReadsMemory;
@@ -514,7 +514,8 @@ TypeBasedAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
     return AliasAnalysis::getModRefInfo(CS, Loc);
 
   if (const MDNode *L = Loc.AATags.TBAA)
-    if (const MDNode *M = CS.getInstruction()->getMDNode(LLVMContext::MD_tbaa))
+    if (const MDNode *M =
+            CS.getInstruction()->getMetadata(LLVMContext::MD_tbaa))
       if (!Aliases(L, M))
         return NoModRef;
 
@@ -527,9 +528,10 @@ TypeBasedAliasAnalysis::getModRefInfo(ImmutableCallSite CS1,
   if (!EnableTBAA)
     return AliasAnalysis::getModRefInfo(CS1, CS2);
 
-  if (const MDNode *M1 = CS1.getInstruction()->getMDNode(LLVMContext::MD_tbaa))
+  if (const MDNode *M1 =
+          CS1.getInstruction()->getMetadata(LLVMContext::MD_tbaa))
     if (const MDNode *M2 =
-            CS2.getInstruction()->getMDNode(LLVMContext::MD_tbaa))
+            CS2.getInstruction()->getMetadata(LLVMContext::MD_tbaa))
       if (!Aliases(M1, M2))
         return NoModRef;
 
@@ -613,20 +615,20 @@ MDNode *MDNode::getMostGenericTBAA(MDNode *A, MDNode *B) {
 void Instruction::getAAMetadata(AAMDNodes &N, bool Merge) const {
   if (Merge)
     N.TBAA =
-        MDNode::getMostGenericTBAA(N.TBAA, getMDNode(LLVMContext::MD_tbaa));
+        MDNode::getMostGenericTBAA(N.TBAA, getMetadata(LLVMContext::MD_tbaa));
   else
-    N.TBAA = getMDNode(LLVMContext::MD_tbaa);
+    N.TBAA = getMetadata(LLVMContext::MD_tbaa);
 
   if (Merge)
     N.Scope =
-        MDNode::intersect(N.Scope, getMDNode(LLVMContext::MD_alias_scope));
+        MDNode::intersect(N.Scope, getMetadata(LLVMContext::MD_alias_scope));
   else
-    N.Scope = getMDNode(LLVMContext::MD_alias_scope);
+    N.Scope = getMetadata(LLVMContext::MD_alias_scope);
 
   if (Merge)
     N.NoAlias =
-        MDNode::intersect(N.NoAlias, getMDNode(LLVMContext::MD_noalias));
+        MDNode::intersect(N.NoAlias, getMetadata(LLVMContext::MD_noalias));
   else
-    N.NoAlias = getMDNode(LLVMContext::MD_noalias);
+    N.NoAlias = getMetadata(LLVMContext::MD_noalias);
 }
 
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index f8b226d9515..9532e34a8c3 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -862,7 +862,7 @@ void computeKnownBits(Value *V, APInt &KnownZero, APInt &KnownOne,
   switch (I->getOpcode()) {
   default: break;
   case Instruction::Load:
-    if (MDNode *MD = cast<LoadInst>(I)->getMDNode(LLVMContext::MD_range))
+    if (MDNode *MD = cast<LoadInst>(I)->getMetadata(LLVMContext::MD_range))
       computeKnownBitsFromRangeMetadata(*MD, KnownZero);
     break;
   case Instruction::And: {
@@ -1258,7 +1258,7 @@ void computeKnownBits(Value *V, APInt &KnownZero, APInt &KnownOne,
   }
   case Instruction::Call:
   case Instruction::Invoke:
-    if (MDNode *MD = cast<Instruction>(I)->getMDNode(LLVMContext::MD_range))
+    if (MDNode *MD = cast<Instruction>(I)->getMetadata(LLVMContext::MD_range))
       computeKnownBitsFromRangeMetadata(*MD, KnownZero);
     // If a range metadata is attached to this IntrinsicInst, intersect the
     // explicit range specified by the metadata and the implicit range of
@@ -1533,7 +1533,7 @@ bool isKnownNonZero(Value *V, const DataLayout *TD, unsigned Depth,
   }
 
   if (Instruction* I = dyn_cast<Instruction>(V)) {
-    if (MDNode *Ranges = I->getMDNode(LLVMContext::MD_range)) {
+    if (MDNode *Ranges = I->getMetadata(LLVMContext::MD_range)) {
       // If the possible ranges don't contain zero, then the value is
       // definitely non-zero.
       if (IntegerType* Ty = dyn_cast<IntegerType>(V->getType())) {
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index ef7a456a35c..96181e54cb1 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -848,7 +848,7 @@ static void WriteMetadataAttachment(const Function &F,
 
   // Write metadata attachments
   // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
-  SmallVector<std::pair<unsigned, Value *>, 4> MDs;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
 
   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
diff --git a/lib/Bitcode/Writer/ValueEnumerator.cpp b/lib/Bitcode/Writer/ValueEnumerator.cpp
index 902bb27c1e9..d72e66c7be2 100644
--- a/lib/Bitcode/Writer/ValueEnumerator.cpp
+++ b/lib/Bitcode/Writer/ValueEnumerator.cpp
@@ -321,7 +321,7 @@ ValueEnumerator::ValueEnumerator(const Module *M) {
   EnumerateValueSymbolTable(M->getValueSymbolTable());
   EnumerateNamedMetadata(M);
 
-  SmallVector<std::pair<unsigned, Value *>, 8> MDs;
+  SmallVector<std::pair<unsigned, MDNode *>, 8> MDs;
 
   // Enumerate types used by function bodies and argument lists.
   for (const Function &F : *M) {
@@ -347,7 +347,7 @@ ValueEnumerator::ValueEnumerator(const Module *M) {
         MDs.clear();
         I.getAllMetadataOtherThanDebugLoc(MDs);
         for (unsigned i = 0, e = MDs.size(); i != e; ++i)
-          EnumerateMetadata(cast<MDNode>(MDs[i].second));
+          EnumerateMetadata(MDs[i].second);
 
         if (!I.getDebugLoc().isUnknown()) {
           MDNode *Scope, *IA;
@@ -741,10 +741,10 @@ void ValueEnumerator::incorporateFunction(const Function &F) {
             FnLocalMDVector.push_back(MD);
       }
 
-      SmallVector<std::pair<unsigned, Value *>, 8> MDs;
+      SmallVector<std::pair<unsigned, MDNode *>, 8> MDs;
       I->getAllMetadataOtherThanDebugLoc(MDs);
       for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
-        auto *N = cast<MDNode>(MDs[i].second);
+        MDNode *N = MDs[i].second;
         if (N->isFunctionLocal() && N->getFunction())
           FnLocalMDVector.push_back(N);
       }
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 087836901a7..32bcd6b8158 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1399,7 +1399,7 @@ void AsmPrinter::EmitModuleIdents(Module &M) {
 
   if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
     for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
-      const MDNode *N = NMD->getOperandAsMDNode(i);
+      const MDNode *N = NMD->getOperand(i);
       assert(N->getNumOperands() == 1 &&
              "llvm.ident metadata entry can have only one operand");
       const MDString *S = cast<MDString>(N->getOperand(0));
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 9523446bd22..4acd7271be9 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -450,8 +450,8 @@ void DwarfDebug::beginModule() {
 
   SingleCU = CU_Nodes->getNumOperands() == 1;
 
-  for (Value *N : CU_Nodes->operands()) {
-    DICompileUnit CUNode(cast<MDNode>(N));
+  for (MDNode *N : CU_Nodes->operands()) {
+    DICompileUnit CUNode(N);
     DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
     DIArray ImportedEntities = CUNode.getImportedEntities();
     for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
@@ -526,8 +526,8 @@ void DwarfDebug::collectDeadVariables() {
   const Module *M = MMI->getModule();
 
   if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
-    for (Value *N : CU_Nodes->operands()) {
-      DICompileUnit TheCU(cast<MDNode>(N));
+    for (MDNode *N : CU_Nodes->operands()) {
+      DICompileUnit TheCU(N);
       // Construct subprogram DIE and add variables DIEs.
       DwarfCompileUnit *SPCU =
           static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index 593173d9c2c..0b2e22486e3 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -2122,9 +2122,9 @@ FastISel::createMachineMemOperandFor(const Instruction *I) const {
   } else
     return nullptr;
 
-  bool IsNonTemporal = I->getMDNode(LLVMContext::MD_nontemporal) != nullptr;
-  bool IsInvariant = I->getMDNode(LLVMContext::MD_invariant_load) != nullptr;
-  const MDNode *Ranges = I->getMDNode(LLVMContext::MD_range);
+  bool IsNonTemporal = I->getMetadata(LLVMContext::MD_nontemporal) != nullptr;
+  bool IsInvariant = I->getMetadata(LLVMContext::MD_invariant_load) != nullptr;
+  const MDNode *Ranges = I->getMetadata(LLVMContext::MD_range);
 
   AAMDNodes AAInfo;
   I->getAAMetadata(AAInfo);
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index cf030b30659..4b4b90b5837 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -3480,13 +3480,13 @@ void SelectionDAGBuilder::visitLoad(const LoadInst &I) {
   Type *Ty = I.getType();
 
   bool isVolatile = I.isVolatile();
-  bool isNonTemporal = I.getMDNode(LLVMContext::MD_nontemporal) != nullptr;
-  bool isInvariant = I.getMDNode(LLVMContext::MD_invariant_load) != nullptr;
+  bool isNonTemporal = I.getMetadata(LLVMContext::MD_nontemporal) != nullptr;
+  bool isInvariant = I.getMetadata(LLVMContext::MD_invariant_load) != nullptr;
   unsigned Alignment = I.getAlignment();
 
   AAMDNodes AAInfo;
   I.getAAMetadata(AAInfo);
-  const MDNode *Ranges = I.getMDNode(LLVMContext::MD_range);
+  const MDNode *Ranges = I.getMetadata(LLVMContext::MD_range);
 
   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
   SmallVector<EVT, 4> ValueVTs;
@@ -3584,7 +3584,7 @@ void SelectionDAGBuilder::visitStore(const StoreInst &I) {
                                           NumValues));
   EVT PtrVT = Ptr.getValueType();
   bool isVolatile = I.isVolatile();
-  bool isNonTemporal = I.getMDNode(LLVMContext::MD_nontemporal) != nullptr;
+  bool isNonTemporal = I.getMetadata(LLVMContext::MD_nontemporal) != nullptr;
   unsigned Alignment = I.getAlignment();
 
   AAMDNodes AAInfo;
@@ -6479,7 +6479,7 @@ void SelectionDAGBuilder::visitInlineAsm(ImmutableCallSite CS) {
   // If we have a !srcloc metadata node associated with it, we want to attach
   // this to the ultimately generated inline asm machineinstr.  To do this, we
   // pass in the third operand as this (potentially null) inline asm MDNode.
-  const MDNode *SrcLoc = CS.getInstruction()->getMDNode("srcloc");
+  const MDNode *SrcLoc = CS.getInstruction()->getMetadata("srcloc");
   AsmNodeOperands.push_back(DAG.getMDNode(SrcLoc));
 
   // Remember the HasSideEffect, AlignStack, AsmDialect, MayLoad and MayStore
diff --git a/lib/IR/AsmWriter.cpp b/lib/IR/AsmWriter.cpp
index d9e3131ce3c..1961a20901e 100644
--- a/lib/IR/AsmWriter.cpp
+++ b/lib/IR/AsmWriter.cpp
@@ -545,7 +545,7 @@ public:
   /// plane.  If something is not in the SlotTracker, return -1.
   int getLocalSlot(const Value *V);
   int getGlobalSlot(const GlobalValue *V);
-  int getMetadataSlot(const Value *MD);
+  int getMetadataSlot(const MDNode *N);
   int getAttributeGroupSlot(AttributeSet AS);
 
   /// If you'd like to deal with a function instead of just a module, use
@@ -585,7 +585,7 @@ private:
   void CreateModuleSlot(const GlobalValue *V);
 
   /// CreateMetadataSlot - Insert the specified MDNode* into the slot table.
-  void CreateMetadataSlot(const Value *MD);
+  void CreateMetadataSlot(const MDNode *N);
 
   /// CreateFunctionSlot - Insert the specified Value* into the slot table.
   void CreateFunctionSlot(const Value *V);
@@ -718,7 +718,7 @@ void SlotTracker::processFunction() {
 
   ST_DEBUG("Inserting Instructions:\n");
 
-  SmallVector<std::pair<unsigned, Value *>, 4> MDForInst;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> MDForInst;
 
   // Add all of the basic blocks and instructions with no names.
   for (Function::const_iterator BB = TheFunction->begin(),
@@ -755,7 +755,7 @@ void SlotTracker::processFunction() {
       // Process metadata attached with this instruction.
       I->getAllMetadata(MDForInst);
       for (unsigned i = 0, e = MDForInst.size(); i != e; ++i)
-        CreateMetadataSlot(cast<MDNode>(MDForInst[i].second));
+        CreateMetadataSlot(MDForInst[i].second);
       MDForInst.clear();
     }
   }
@@ -786,13 +786,13 @@ int SlotTracker::getGlobalSlot(const GlobalValue *V) {
   return MI == mMap.end() ? -1 : (int)MI->second;
 }
 
-/// getMetadataSlot - Get the slot number of a metadata node.
-int SlotTracker::getMetadataSlot(const Value *MD) {
+/// getMetadataSlot - Get the slot number of a MDNode.
+int SlotTracker::getMetadataSlot(const MDNode *N) {
   // Check for uninitialized state and do lazy initialization.
   initialize();
 
   // Find the MDNode in the module map
-  mdn_iterator MI = mdnMap.find(cast<MDNode>(MD));
+  mdn_iterator MI = mdnMap.find(N);
   return MI == mdnMap.end() ? -1 : (int)MI->second;
 }
 
@@ -846,10 +846,9 @@ void SlotTracker::CreateFunctionSlot(const Value *V) {
            DestSlot << " [o]\n");
 }
 
-/// CreateModuleSlot - Insert the specified metadata into the slot table.
-void SlotTracker::CreateMetadataSlot(const Value *MD) {
-  assert(MD && "Can't insert a null Value into SlotTracker!");
-  const MDNode *N = cast<MDNode>(MD);
+/// CreateModuleSlot - Insert the specified MDNode* into the slot table.
+void SlotTracker::CreateMetadataSlot(const MDNode *N) {
+  assert(N && "Can't insert a null Value into SlotTracker!");
 
   // Don't insert if N is a function-local metadata, these are always printed
   // inline.
@@ -2316,7 +2315,7 @@ void AssemblyWriter::printInstruction(const Instruction &I) {
   }
 
   // Print Metadata info.
-  SmallVector<std::pair<unsigned, Value *>, 4> InstMD;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> InstMD;
   I.getAllMetadata(InstMD);
   if (!InstMD.empty()) {
     SmallVector<StringRef, 8> MDNames;
@@ -2329,8 +2328,8 @@ void AssemblyWriter::printInstruction(const Instruction &I) {
          Out << ", !<unknown kind #" << Kind << ">";
        }
       Out << ' ';
-      WriteAsOperandInternal(Out, cast<MDNode>(InstMD[i].second), &TypePrinter,
-                             &Machine, TheModule);
+      WriteAsOperandInternal(Out, InstMD[i].second, &TypePrinter, &Machine,
+                             TheModule);
     }
   }
   printInfoComment(I);
diff --git a/lib/IR/AutoUpgrade.cpp b/lib/IR/AutoUpgrade.cpp
index 3800d70fc6c..c24dfead433 100644
--- a/lib/IR/AutoUpgrade.cpp
+++ b/lib/IR/AutoUpgrade.cpp
@@ -571,7 +571,7 @@ void llvm::UpgradeCallsToIntrinsic(Function* F) {
 }
 
 void llvm::UpgradeInstWithTBAATag(Instruction *I) {
-  MDNode *MD = I->getMDNode(LLVMContext::MD_tbaa);
+  MDNode *MD = I->getMetadata(LLVMContext::MD_tbaa);
   assert(MD && "UpgradeInstWithTBAATag should have a TBAA tag");
   // Check if the tag uses struct-path aware TBAA format.
   if (isa<MDNode>(MD->getOperand(0)) && MD->getNumOperands() >= 3)
diff --git a/lib/IR/Core.cpp b/lib/IR/Core.cpp
index 7e60e05fd00..3576137dd30 100644
--- a/lib/IR/Core.cpp
+++ b/lib/IR/Core.cpp
@@ -561,7 +561,7 @@ LLVMValueRef LLVMGetMetadata(LLVMValueRef Inst, unsigned KindID) {
 
 void LLVMSetMetadata(LLVMValueRef Inst, unsigned KindID, LLVMValueRef MD) {
   unwrap<Instruction>(Inst)
-      ->setMetadata(KindID, MD ? unwrap<Value>(MD) : nullptr);
+      ->setMetadata(KindID, MD ? unwrap<MDNode>(MD) : nullptr);
 }
 
 /*--.. Conversion functions ................................................--*/
@@ -720,7 +720,7 @@ void LLVMAddNamedMetadataOperand(LLVMModuleRef M, const char* name,
   NamedMDNode *N = unwrap(M)->getOrInsertNamedMetadata(name);
   if (!N)
     return;
-  Value *Op = Val ? unwrap<Value>(Val) : nullptr;
+  MDNode *Op = Val ? unwrap<MDNode>(Val) : nullptr;
   if (Op)
     N->addOperand(Op);
 }
diff --git a/lib/IR/DebugInfo.cpp b/lib/IR/DebugInfo.cpp
index 38389e8ca1e..60904c2b356 100644
--- a/lib/IR/DebugInfo.cpp
+++ b/lib/IR/DebugInfo.cpp
@@ -949,7 +949,7 @@ DITypeIdentifierMap
 llvm::generateDITypeIdentifierMap(const NamedMDNode *CU_Nodes) {
   DITypeIdentifierMap Map;
   for (unsigned CUi = 0, CUe = CU_Nodes->getNumOperands(); CUi != CUe; ++CUi) {
-    DICompileUnit CU(CU_Nodes->getOperandAsMDNode(CUi));
+    DICompileUnit CU(CU_Nodes->getOperand(CUi));
     DIArray Retain = CU.getRetainedTypes();
     for (unsigned Ti = 0, Te = Retain.getNumElements(); Ti != Te; ++Ti) {
       if (!Retain.getElement(Ti).isCompositeType())
@@ -997,7 +997,7 @@ void DebugInfoFinder::processModule(const Module &M) {
   InitializeTypeMap(M);
   if (NamedMDNode *CU_Nodes = M.getNamedMetadata("llvm.dbg.cu")) {
     for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
-      DICompileUnit CU(CU_Nodes->getOperandAsMDNode(i));
+      DICompileUnit CU(CU_Nodes->getOperand(i));
       addCompileUnit(CU);
       DIArray GVs = CU.getGlobalVariables();
       for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i) {
@@ -1542,8 +1542,8 @@ llvm::makeSubprogramMap(const Module &M) {
   if (!CU_Nodes)
     return R;
 
-  for (Value *N : CU_Nodes->operands()) {
-    DICompileUnit CUNode(cast<MDNode>(N));
+  for (MDNode *N : CU_Nodes->operands()) {
+    DICompileUnit CUNode(N);
     DIArray SPs = CUNode.getSubprograms();
     for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
       DISubprogram SP(SPs.getElement(i));
diff --git a/lib/IR/DiagnosticInfo.cpp b/lib/IR/DiagnosticInfo.cpp
index c0552c90ae6..37cce2b0d78 100644
--- a/lib/IR/DiagnosticInfo.cpp
+++ b/lib/IR/DiagnosticInfo.cpp
@@ -96,7 +96,7 @@ DiagnosticInfoInlineAsm::DiagnosticInfoInlineAsm(const Instruction &I,
                                                  DiagnosticSeverity Severity)
     : DiagnosticInfo(DK_InlineAsm, Severity), LocCookie(0), MsgStr(MsgStr),
       Instr(&I) {
-  if (const MDNode *SrcLoc = I.getMDNode("srcloc")) {
+  if (const MDNode *SrcLoc = I.getMetadata("srcloc")) {
     if (SrcLoc->getNumOperands() != 0)
       if (const ConstantInt *CI = dyn_cast<ConstantInt>(SrcLoc->getOperand(0)))
         LocCookie = CI->getZExtValue();
diff --git a/lib/IR/Instruction.cpp b/lib/IR/Instruction.cpp
index a2bbb563db4..3ee66f56981 100644
--- a/lib/IR/Instruction.cpp
+++ b/lib/IR/Instruction.cpp
@@ -548,7 +548,7 @@ Instruction *Instruction::clone() const {
 
   // Otherwise, enumerate and copy over metadata from the old instruction to the
   // new one.
-  SmallVector<std::pair<unsigned, Value *>, 4> TheMDs;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> TheMDs;
   getAllMetadataOtherThanDebugLoc(TheMDs);
   for (const auto &MD : TheMDs)
     New->setMetadata(MD.first, MD.second);
diff --git a/lib/IR/Instructions.cpp b/lib/IR/Instructions.cpp
index 6aaea75896e..4b48d7d6eb0 100644
--- a/lib/IR/Instructions.cpp
+++ b/lib/IR/Instructions.cpp
@@ -791,7 +791,7 @@ void BranchInst::swapSuccessors() {
 
   // Update profile metadata if present and it matches our structural
   // expectations.
-  MDNode *ProfileData = getMDNode(LLVMContext::MD_prof);
+  MDNode *ProfileData = getMetadata(LLVMContext::MD_prof);
   if (!ProfileData || ProfileData->getNumOperands() != 3)
     return;
 
@@ -2072,7 +2072,8 @@ void BinaryOperator::andIRFlags(const Value *V) {
 /// An accuracy of 0.0 means that the operation should be performed with the
 /// default precision.
 float FPMathOperator::getFPAccuracy() const {
-  const MDNode *MD = cast<Instruction>(this)->getMDNode(LLVMContext::MD_fpmath);
+  const MDNode *MD =
+      cast<Instruction>(this)->getMetadata(LLVMContext::MD_fpmath);
   if (!MD)
     return 0.0;
   ConstantFP *Accuracy = cast<ConstantFP>(MD->getOperand(0));
diff --git a/lib/IR/Metadata.cpp b/lib/IR/Metadata.cpp
index 59beb734184..1fb15a075a6 100644
--- a/lib/IR/Metadata.cpp
+++ b/lib/IR/Metadata.cpp
@@ -555,13 +555,13 @@ MDNode *MDNode::getMostGenericRange(MDNode *A, MDNode *B) {
 // NamedMDNode implementation.
 //
 
-static SmallVector<TrackingVH<Value>, 4> &getNMDOps(void *Operands) {
-  return *(SmallVector<TrackingVH<Value>, 4> *)Operands;
+static SmallVector<TrackingVH<MDNode>, 4> &getNMDOps(void *Operands) {
+  return *(SmallVector<TrackingVH<MDNode>, 4> *)Operands;
 }
 
 NamedMDNode::NamedMDNode(const Twine &N)
     : Name(N.str()), Parent(nullptr),
-      Operands(new SmallVector<TrackingVH<Value>, 4>()) {}
+      Operands(new SmallVector<TrackingVH<MDNode>, 4>()) {}
 
 NamedMDNode::~NamedMDNode() {
   dropAllReferences();
@@ -572,16 +572,15 @@ unsigned NamedMDNode::getNumOperands() const {
   return (unsigned)getNMDOps(Operands).size();
 }
 
-Value *NamedMDNode::getOperand(unsigned i) const {
+MDNode *NamedMDNode::getOperand(unsigned i) const {
   assert(i < getNumOperands() && "Invalid Operand number!");
   return &*getNMDOps(Operands)[i];
 }
 
-void NamedMDNode::addOperand(Value *V) {
-  auto *M = cast<MDNode>(V);
+void NamedMDNode::addOperand(MDNode *M) {
   assert(!M->isFunctionLocal() &&
          "NamedMDNode operands must not be function-local!");
-  getNMDOps(Operands).push_back(TrackingVH<Value>(M));
+  getNMDOps(Operands).push_back(TrackingVH<MDNode>(M));
 }
 
 void NamedMDNode::eraseFromParent() {
@@ -600,23 +599,16 @@ StringRef NamedMDNode::getName() const {
 // Instruction Metadata method implementations.
 //
 
-void Instruction::setMetadata(StringRef Kind, Value *MD) {
-  if (!MD && !hasMetadata()) return;
-  setMetadata(getContext().getMDKindID(Kind), MD);
+void Instruction::setMetadata(StringRef Kind, MDNode *Node) {
+  if (!Node && !hasMetadata())
+    return;
+  setMetadata(getContext().getMDKindID(Kind), Node);
 }
 
-Value *Instruction::getMetadataImpl(StringRef Kind) const {
+MDNode *Instruction::getMetadataImpl(StringRef Kind) const {
   return getMetadataImpl(getContext().getMDKindID(Kind));
 }
 
-MDNode *Instruction::getMDNodeImpl(unsigned KindID) const {
-  return cast_or_null<MDNode>(getMetadataImpl(KindID));
-}
-
-MDNode *Instruction::getMDNodeImpl(StringRef Kind) const {
-  return cast_or_null<MDNode>(getMetadataImpl(Kind));
-}
-
 void Instruction::dropUnknownMetadata(ArrayRef<unsigned> KnownIDs) {
   SmallSet<unsigned, 5> KnownSet;
   KnownSet.insert(KnownIDs.begin(), KnownIDs.end());
@@ -663,12 +655,10 @@ void Instruction::dropUnknownMetadata(ArrayRef<unsigned> KnownIDs) {
 
 /// setMetadata - Set the metadata of of the specified kind to the specified
 /// node.  This updates/replaces metadata if already present, or removes it if
-/// MD is null.
-void Instruction::setMetadata(unsigned KindID, Value *MD) {
-  if (!MD && !hasMetadata()) return;
-
-  // For now, we only expect MDNodes here.
-  MDNode *Node = cast_or_null<MDNode>(MD);
+/// Node is null.
+void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
+  if (!Node && !hasMetadata())
+    return;
 
   // Handle 'dbg' as a special case since it is not stored in the hash table.
   if (KindID == LLVMContext::MD_dbg) {
@@ -729,7 +719,7 @@ void Instruction::setAAMetadata(const AAMDNodes &N) {
   setMetadata(LLVMContext::MD_noalias, N.NoAlias);
 }
 
-Value *Instruction::getMetadataImpl(unsigned KindID) const {
+MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
   // Handle 'dbg' as a special case since it is not stored in the hash table.
   if (KindID == LLVMContext::MD_dbg)
     return DbgLoc.getAsMDNode(getContext());
@@ -746,7 +736,7 @@ Value *Instruction::getMetadataImpl(unsigned KindID) const {
 }
 
 void Instruction::getAllMetadataImpl(
-    SmallVectorImpl<std::pair<unsigned, Value *>> &Result) const {
+    SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
   Result.clear();
   
   // Handle 'dbg' as a special case since it is not stored in the hash table.
@@ -771,7 +761,7 @@ void Instruction::getAllMetadataImpl(
 }
 
 void Instruction::getAllMetadataOtherThanDebugLocImpl(
-    SmallVectorImpl<std::pair<unsigned, Value *>> &Result) const {
+    SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
   Result.clear();
   assert(hasMetadataHashEntry() &&
          getContext().pImpl->MetadataStore.count(this) &&
diff --git a/lib/IR/Module.cpp b/lib/IR/Module.cpp
index bc50db3f56c..28743fae6cd 100644
--- a/lib/IR/Module.cpp
+++ b/lib/IR/Module.cpp
@@ -276,8 +276,7 @@ getModuleFlagsMetadata(SmallVectorImpl<ModuleFlagEntry> &Flags) const {
   const NamedMDNode *ModFlags = getModuleFlagsMetadata();
   if (!ModFlags) return;
 
-  for (const Value *FlagMD : ModFlags->operands()) {
-    const MDNode *Flag = cast<MDNode>(FlagMD);
+  for (const MDNode *Flag : ModFlags->operands()) {
     ModFlagBehavior MFB;
     if (Flag->getNumOperands() >= 3 &&
         isValidModFlagBehavior(Flag->getOperand(0), MFB) &&
diff --git a/lib/IR/TypeFinder.cpp b/lib/IR/TypeFinder.cpp
index 3aae4e69ec1..6796075bfc2 100644
--- a/lib/IR/TypeFinder.cpp
+++ b/lib/IR/TypeFinder.cpp
@@ -40,7 +40,7 @@ void TypeFinder::run(const Module &M, bool onlyNamed) {
   }
 
   // Get types from functions.
-  SmallVector<std::pair<unsigned, Value *>, 4> MDForInst;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> MDForInst;
   for (Module::const_iterator FI = M.begin(), E = M.end(); FI != E; ++FI) {
     incorporateType(FI->getType());
 
@@ -71,7 +71,7 @@ void TypeFinder::run(const Module &M, bool onlyNamed) {
         // Incorporate types hiding in metadata.
         I.getAllMetadataOtherThanDebugLoc(MDForInst);
         for (unsigned i = 0, e = MDForInst.size(); i != e; ++i)
-          incorporateMDNode(cast<MDNode>(MDForInst[i].second));
+          incorporateMDNode(MDForInst[i].second);
 
         MDForInst.clear();
       }
@@ -81,7 +81,7 @@ void TypeFinder::run(const Module &M, bool onlyNamed) {
          E = M.named_metadata_end(); I != E; ++I) {
     const NamedMDNode *NMD = I;
     for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
-      incorporateMDNode(NMD->getOperandAsMDNode(i));
+      incorporateMDNode(NMD->getOperand(i));
   }
 }
 
diff --git a/lib/IR/Verifier.cpp b/lib/IR/Verifier.cpp
index 395f2e74d61..f9302910d39 100644
--- a/lib/IR/Verifier.cpp
+++ b/lib/IR/Verifier.cpp
@@ -555,7 +555,7 @@ void Verifier::visitGlobalAlias(const GlobalAlias &GA) {
 
 void Verifier::visitNamedMDNode(const NamedMDNode &NMD) {
   for (unsigned i = 0, e = NMD.getNumOperands(); i != e; ++i) {
-    MDNode *MD = NMD.getOperandAsMDNode(i);
+    MDNode *MD = NMD.getOperand(i);
     if (!MD)
       continue;
 
@@ -624,7 +624,7 @@ void Verifier::visitModuleIdents(const Module &M) {
   // llvm.ident takes a list of metadata entry. Each entry has only one string.
   // Scan each llvm.ident entry and make sure that this requirement is met.
   for (unsigned i = 0, e = Idents->getNumOperands(); i != e; ++i) {
-    const MDNode *N = Idents->getOperandAsMDNode(i);
+    const MDNode *N = Idents->getOperand(i);
     Assert1(N->getNumOperands() == 1,
             "incorrect number of operands in llvm.ident metadata", N);
     Assert1(isa<MDString>(N->getOperand(0)),
@@ -642,7 +642,7 @@ void Verifier::visitModuleFlags(const Module &M) {
   DenseMap<const MDString*, const MDNode*> SeenIDs;
   SmallVector<const MDNode*, 16> Requirements;
   for (unsigned I = 0, E = Flags->getNumOperands(); I != E; ++I) {
-    visitModuleFlag(Flags->getOperandAsMDNode(I), SeenIDs, Requirements);
+    visitModuleFlag(Flags->getOperand(I), SeenIDs, Requirements);
   }
 
   // Validate that the requirements in the module are valid.
@@ -2267,7 +2267,7 @@ void Verifier::visitInstruction(Instruction &I) {
     }
   }
 
-  if (MDNode *MD = I.getMDNode(LLVMContext::MD_fpmath)) {
+  if (MDNode *MD = I.getMetadata(LLVMContext::MD_fpmath)) {
     Assert1(I.getType()->isFPOrFPVectorTy(),
             "fpmath requires a floating point result!", &I);
     Assert1(MD->getNumOperands() == 1, "fpmath takes one operand!", &I);
@@ -2281,7 +2281,7 @@ void Verifier::visitInstruction(Instruction &I) {
     }
   }
 
-  if (MDNode *Range = I.getMDNode(LLVMContext::MD_range)) {
+  if (MDNode *Range = I.getMetadata(LLVMContext::MD_range)) {
     Assert1(isa<LoadInst>(I) || isa<CallInst>(I) || isa<InvokeInst>(I),
             "Ranges are only for loads, calls and invokes!", &I);
     visitRangeMetadata(I, Range, I.getType());
@@ -2587,7 +2587,7 @@ void DebugInfoVerifier::verifyDebugInfo() {
 void DebugInfoVerifier::processInstructions(DebugInfoFinder &Finder) {
   for (const Function &F : *M)
     for (auto I = inst_begin(&F), E = inst_end(&F); I != E; ++I) {
-      if (MDNode *MD = I->getMDNode(LLVMContext::MD_dbg))
+      if (MDNode *MD = I->getMetadata(LLVMContext::MD_dbg))
         Finder.processLocation(*M, DILocation(MD));
       if (const CallInst *CI = dyn_cast<CallInst>(&*I))
         processCallInst(Finder, *CI);
diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp
index 3a2eb6c178c..bac187bb3a3 100644
--- a/lib/Linker/LinkModules.cpp
+++ b/lib/Linker/LinkModules.cpp
@@ -1287,7 +1287,7 @@ bool ModuleLinker::linkModuleFlagsMetadata() {
   DenseMap<MDString*, MDNode*> Flags;
   SmallSetVector<MDNode*, 16> Requirements;
   for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
-    MDNode *Op = DstModFlags->getOperandAsMDNode(I);
+    MDNode *Op = DstModFlags->getOperand(I);
     ConstantInt *Behavior = cast<ConstantInt>(Op->getOperand(0));
     MDString *ID = cast<MDString>(Op->getOperand(1));
 
@@ -1302,7 +1302,7 @@ bool ModuleLinker::linkModuleFlagsMetadata() {
   // requirements.
   bool HasErr = false;
   for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
-    MDNode *SrcOp = SrcModFlags->getOperandAsMDNode(I);
+    MDNode *SrcOp = SrcModFlags->getOperand(I);
     ConstantInt *SrcBehavior = cast<ConstantInt>(SrcOp->getOperand(0));
     MDString *ID = cast<MDString>(SrcOp->getOperand(1));
     MDNode *DstOp = Flags.lookup(ID);
diff --git a/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp b/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
index 496cfbd7955..58fa95b54ac 100644
--- a/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
+++ b/lib/Target/NVPTX/NVPTXGenericToNVVM.cpp
@@ -371,7 +371,7 @@ void GenericToNVVM::remapNamedMDNode(Module *M, NamedMDNode *N) {
   // Check if any operand is or contains a global variable in  GVMap, and thus
   // converted to another value.
   for (unsigned i = 0; i < NumOperands; ++i) {
-    MDNode *Operand = cast<MDNode>(N->getOperand(i));
+    MDNode *Operand = N->getOperand(i);
     MDNode *NewOperand = remapMDNode(M, Operand);
     OperandChanged |= Operand != NewOperand;
     NewOperands.push_back(NewOperand);
diff --git a/lib/Target/NVPTX/NVPTXUtilities.cpp b/lib/Target/NVPTX/NVPTXUtilities.cpp
index f1a9a6cc1ea..5caa8bd12ca 100644
--- a/lib/Target/NVPTX/NVPTXUtilities.cpp
+++ b/lib/Target/NVPTX/NVPTXUtilities.cpp
@@ -73,7 +73,7 @@ static void cacheAnnotationFromMD(const Module *m, const GlobalValue *gv) {
     return;
   key_val_pair_t tmp;
   for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
-    const MDNode *elem = NMD->getOperandAsMDNode(i);
+    const MDNode *elem = NMD->getOperand(i);
 
     Value *entity = elem->getOperand(0);
     // entity may be null due to DCE
@@ -319,7 +319,7 @@ bool llvm::getAlign(const Function &F, unsigned index, unsigned &align) {
 }
 
 bool llvm::getAlign(const CallInst &I, unsigned index, unsigned &align) {
-  if (MDNode *alignNode = I.getMDNode("callalign")) {
+  if (MDNode *alignNode = I.getMetadata("callalign")) {
     for (int i = 0, n = alignNode->getNumOperands(); i < n; i++) {
       if (const ConstantInt *CI =
               dyn_cast<ConstantInt>(alignNode->getOperand(i))) {
diff --git a/lib/Target/R600/SITypeRewriter.cpp b/lib/Target/R600/SITypeRewriter.cpp
index f32b1e4ef7b..9318dc11d55 100644
--- a/lib/Target/R600/SITypeRewriter.cpp
+++ b/lib/Target/R600/SITypeRewriter.cpp
@@ -87,8 +87,7 @@ void SITypeRewriter::visitLoadInst(LoadInst &I) {
     Value *BitCast = Builder.CreateBitCast(Ptr,
         PointerType::get(v4i32,PtrTy->getPointerAddressSpace()));
     LoadInst *Load = Builder.CreateLoad(BitCast);
-    // FIXME: Should the DebugLoc really get dropped here?
-    SmallVector<std::pair<unsigned, Value *>, 8> MD;
+    SmallVector<std::pair<unsigned, MDNode *>, 8> MD;
     I.getAllMetadataOtherThanDebugLoc(MD);
     for (unsigned i = 0, e = MD.size(); i != e; ++i) {
       Load->setMetadata(MD[i].first, MD[i].second);
diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 3b20662068d..5a70d8bb640 100644
--- a/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -117,7 +117,7 @@ Instruction *InstCombiner::SimplifyMemTransfer(MemIntrinsic *MI) {
 
         // If the memcpy has metadata describing the members, see if we can
         // get the TBAA tag describing our copy.
-        if (MDNode *M = MI->getMDNode(LLVMContext::MD_tbaa_struct)) {
+        if (MDNode *M = MI->getMetadata(LLVMContext::MD_tbaa_struct)) {
           if (M->getNumOperands() == 3 &&
               M->getOperand(0) &&
               isa<ConstantInt>(M->getOperand(0)) &&
diff --git a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index ebbb9ec08c5..f3ac44cbd6b 100644
--- a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -304,7 +304,7 @@ Instruction *InstCombiner::visitAllocaInst(AllocaInst &AI) {
 static LoadInst *combineLoadToNewType(InstCombiner &IC, LoadInst &LI, Type *NewTy) {
   Value *Ptr = LI.getPointerOperand();
   unsigned AS = LI.getPointerAddressSpace();
-  SmallVector<std::pair<unsigned, Value *>, 8> MD;
+  SmallVector<std::pair<unsigned, MDNode *>, 8> MD;
   LI.getAllMetadata(MD);
 
   LoadInst *NewLoad = IC.Builder->CreateAlignedLoad(
@@ -312,7 +312,7 @@ static LoadInst *combineLoadToNewType(InstCombiner &IC, LoadInst &LI, Type *NewT
       LI.getAlignment(), LI.getName());
   for (const auto &MDPair : MD) {
     unsigned ID = MDPair.first;
-    Value *N = MDPair.second;
+    MDNode *N = MDPair.second;
     // Note, essentially every kind of metadata should be preserved here! This
     // routine is supposed to clone a load instruction changing *only its type*.
     // The only metadata it makes sense to drop is metadata which is invalidated
diff --git a/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 49eccad1d97..3e62165c7b4 100644
--- a/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -256,9 +256,7 @@ class GlobalsMetadata {
     NamedMDNode *Globals = M.getNamedMetadata("llvm.asan.globals");
     if (!Globals)
       return;
-    for (const Value *MDV : Globals->operands()) {
-      const MDNode *MDN = cast<MDNode>(MDV);
-
+    for (auto MDN : Globals->operands()) {
       // Metadata node contains the global and the fields of "Entry".
       assert(MDN->getNumOperands() == 5);
       Value *V = MDN->getOperand(0);
diff --git a/lib/Transforms/Instrumentation/DebugIR.cpp b/lib/Transforms/Instrumentation/DebugIR.cpp
index 7a0ed81eed6..5234341b32e 100644
--- a/lib/Transforms/Instrumentation/DebugIR.cpp
+++ b/lib/Transforms/Instrumentation/DebugIR.cpp
@@ -474,7 +474,7 @@ bool getSourceInfoFromDI(const Module &M, std::string &Directory,
   if (!CUNode || CUNode->getNumOperands() == 0)
     return false;
 
-  DICompileUnit CU(cast<MDNode>(CUNode->getOperand(0)));
+  DICompileUnit CU(CUNode->getOperand(0));
   if (!CU.Verify())
     return false;
 
diff --git a/lib/Transforms/Instrumentation/GCOVProfiling.cpp b/lib/Transforms/Instrumentation/GCOVProfiling.cpp
index 0c666ffea6a..220d7f8b490 100644
--- a/lib/Transforms/Instrumentation/GCOVProfiling.cpp
+++ b/lib/Transforms/Instrumentation/GCOVProfiling.cpp
@@ -417,7 +417,7 @@ namespace {
 std::string GCOVProfiler::mangleName(DICompileUnit CU, const char *NewStem) {
   if (NamedMDNode *GCov = M->getNamedMetadata("llvm.gcov")) {
     for (int i = 0, e = GCov->getNumOperands(); i != e; ++i) {
-      MDNode *N = GCov->getOperandAsMDNode(i);
+      MDNode *N = GCov->getOperand(i);
       if (N->getNumOperands() != 2) continue;
       MDString *GCovFile = dyn_cast<MDString>(N->getOperand(0));
       MDNode *CompileUnit = dyn_cast<MDNode>(N->getOperand(1));
@@ -479,7 +479,7 @@ void GCOVProfiler::emitProfileNotes() {
     // this pass over the original .o's as they're produced, or run it after
     // LTO, we'll generate the same .gcno files.
 
-    DICompileUnit CU(CU_Nodes->getOperandAsMDNode(i));
+    DICompileUnit CU(CU_Nodes->getOperand(i));
     std::error_code EC;
     raw_fd_ostream out(mangleName(CU, "gcno"), EC, sys::fs::F_None);
     std::string EdgeDestinations;
@@ -566,7 +566,7 @@ bool GCOVProfiler::emitProfileArcs() {
   bool Result = false;
   bool InsertIndCounterIncrCode = false;
   for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
-    DICompileUnit CU(CU_Nodes->getOperandAsMDNode(i));
+    DICompileUnit CU(CU_Nodes->getOperand(i));
     DIArray SPs = CU.getSubprograms();
     SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP;
     for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
@@ -847,7 +847,7 @@ Function *GCOVProfiler::insertCounterWriteout(
   NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
   if (CU_Nodes) {
     for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
-      DICompileUnit CU(CU_Nodes->getOperandAsMDNode(i));
+      DICompileUnit CU(CU_Nodes->getOperand(i));
       std::string FilenameGcda = mangleName(CU, "gcda");
       uint32_t CfgChecksum = FileChecksums.empty() ? 0 : FileChecksums[i];
       Builder.CreateCall3(StartFile,
diff --git a/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
index 4536510c8e5..417f2a1649b 100644
--- a/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
@@ -231,7 +231,7 @@ bool ThreadSanitizer::doInitialization(Module &M) {
 }
 
 static bool isVtableAccess(Instruction *I) {
-  if (MDNode *Tag = I->getMDNode(LLVMContext::MD_tbaa))
+  if (MDNode *Tag = I->getMetadata(LLVMContext::MD_tbaa))
     return Tag->isTBAAVtableAccess();
   return false;
 }
diff --git a/lib/Transforms/ObjCARC/ObjCARCContract.cpp b/lib/Transforms/ObjCARC/ObjCARCContract.cpp
index 04a0d917224..eb325eb9417 100644
--- a/lib/Transforms/ObjCARC/ObjCARCContract.cpp
+++ b/lib/Transforms/ObjCARC/ObjCARCContract.cpp
@@ -305,7 +305,7 @@ bool ObjCARCContract::doInitialization(Module &M) {
   if (NamedMDNode *NMD =
         M.getNamedMetadata("clang.arc.retainAutoreleasedReturnValueMarker"))
     if (NMD->getNumOperands() == 1) {
-      const MDNode *N = NMD->getOperandAsMDNode(0);
+      const MDNode *N = NMD->getOperand(0);
       if (N->getNumOperands() == 1)
         if (const MDString *S = dyn_cast<MDString>(N->getOperand(0)))
           RetainRVMarker = S;
diff --git a/lib/Transforms/ObjCARC/ObjCARCOpts.cpp b/lib/Transforms/ObjCARC/ObjCARCOpts.cpp
index 4846282e90e..3da2a543083 100644
--- a/lib/Transforms/ObjCARC/ObjCARCOpts.cpp
+++ b/lib/Transforms/ObjCARC/ObjCARCOpts.cpp
@@ -825,7 +825,7 @@ static MDString *AppendMDNodeToSourcePtr(unsigned NodeId,
   // reference to said Node. Otherwise just return 0.
   if (Instruction *Inst = dyn_cast<Instruction>(Ptr)) {
     MDNode *Node;
-    if (!(Node = Inst->getMDNode(NodeId))) {
+    if (!(Node = Inst->getMetadata(NodeId))) {
       // We do not have any node. Generate and attatch the hash MDString to the
       // instruction.
 
@@ -1736,7 +1736,7 @@ ObjCARCOpt::VisitInstructionBottomUp(Instruction *Inst,
       NestingDetected = true;
     }
 
-    MDNode *ReleaseMetadata = Inst->getMDNode(ImpreciseReleaseMDKind);
+    MDNode *ReleaseMetadata = Inst->getMetadata(ImpreciseReleaseMDKind);
     Sequence NewSeq = ReleaseMetadata ? S_MovableRelease : S_Release;
     ANNOTATE_BOTTOMUP(Inst, Arg, S.GetSeq(), NewSeq);
     S.ResetSequenceProgress(NewSeq);
@@ -2017,7 +2017,7 @@ ObjCARCOpt::VisitInstructionTopDown(Instruction *Inst,
 
     Sequence OldSeq = S.GetSeq();
 
-    MDNode *ReleaseMetadata = Inst->getMDNode(ImpreciseReleaseMDKind);
+    MDNode *ReleaseMetadata = Inst->getMetadata(ImpreciseReleaseMDKind);
 
     switch (OldSeq) {
     case S_Retain:
diff --git a/lib/Transforms/Scalar/Scalarizer.cpp b/lib/Transforms/Scalar/Scalarizer.cpp
index 0ad7cea6392..6036c099be0 100644
--- a/lib/Transforms/Scalar/Scalarizer.cpp
+++ b/lib/Transforms/Scalar/Scalarizer.cpp
@@ -327,11 +327,14 @@ bool Scalarizer::canTransferMetadata(unsigned Tag) {
 // Transfer metadata from Op to the instructions in CV if it is known
 // to be safe to do so.
 void Scalarizer::transferMetadata(Instruction *Op, const ValueVector &CV) {
-  SmallVector<std::pair<unsigned, Value *>, 4> MDs;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
   Op->getAllMetadataOtherThanDebugLoc(MDs);
   for (unsigned I = 0, E = CV.size(); I != E; ++I) {
     if (Instruction *New = dyn_cast<Instruction>(CV[I])) {
-      for (auto MI = MDs.begin(), ME = MDs.end(); MI != ME; ++MI)
+      for (SmallVectorImpl<std::pair<unsigned, MDNode *>>::iterator
+               MI = MDs.begin(),
+               ME = MDs.end();
+           MI != ME; ++MI)
         if (canTransferMetadata(MI->first))
           New->setMetadata(MI->first, MI->second);
       New->setDebugLoc(Op->getDebugLoc());
diff --git a/lib/Transforms/Utils/InlineFunction.cpp b/lib/Transforms/Utils/InlineFunction.cpp
index a1e42bbe70c..2d0b7dcc71c 100644
--- a/lib/Transforms/Utils/InlineFunction.cpp
+++ b/lib/Transforms/Utils/InlineFunction.cpp
@@ -297,9 +297,9 @@ static void CloneAliasScopeMetadata(CallSite CS, ValueToValueMapTy &VMap) {
   for (Function::const_iterator I = CalledFunc->begin(), IE = CalledFunc->end();
        I != IE; ++I)
     for (BasicBlock::const_iterator J = I->begin(), JE = I->end(); J != JE; ++J) {
-      if (const MDNode *M = J->getMDNode(LLVMContext::MD_alias_scope))
+      if (const MDNode *M = J->getMetadata(LLVMContext::MD_alias_scope))
         MD.insert(M);
-      if (const MDNode *M = J->getMDNode(LLVMContext::MD_noalias))
+      if (const MDNode *M = J->getMetadata(LLVMContext::MD_noalias))
         MD.insert(M);
     }
 
@@ -359,31 +359,32 @@ static void CloneAliasScopeMetadata(CallSite CS, ValueToValueMapTy &VMap) {
     if (!NI)
       continue;
 
-    if (MDNode *M = NI->getMDNode(LLVMContext::MD_alias_scope)) {
+    if (MDNode *M = NI->getMetadata(LLVMContext::MD_alias_scope)) {
       MDNode *NewMD = MDMap[M];
       // If the call site also had alias scope metadata (a list of scopes to
       // which instructions inside it might belong), propagate those scopes to
       // the inlined instructions.
       if (MDNode *CSM =
-              CS.getInstruction()->getMDNode(LLVMContext::MD_alias_scope))
+              CS.getInstruction()->getMetadata(LLVMContext::MD_alias_scope))
         NewMD = MDNode::concatenate(NewMD, CSM);
       NI->setMetadata(LLVMContext::MD_alias_scope, NewMD);
     } else if (NI->mayReadOrWriteMemory()) {
       if (MDNode *M =
-              CS.getInstruction()->getMDNode(LLVMContext::MD_alias_scope))
+              CS.getInstruction()->getMetadata(LLVMContext::MD_alias_scope))
         NI->setMetadata(LLVMContext::MD_alias_scope, M);
     }
 
-    if (MDNode *M = NI->getMDNode(LLVMContext::MD_noalias)) {
+    if (MDNode *M = NI->getMetadata(LLVMContext::MD_noalias)) {
       MDNode *NewMD = MDMap[M];
       // If the call site also had noalias metadata (a list of scopes with
       // which instructions inside it don't alias), propagate those scopes to
       // the inlined instructions.
-      if (MDNode *CSM = CS.getInstruction()->getMDNode(LLVMContext::MD_noalias))
+      if (MDNode *CSM =
+              CS.getInstruction()->getMetadata(LLVMContext::MD_noalias))
         NewMD = MDNode::concatenate(NewMD, CSM);
       NI->setMetadata(LLVMContext::MD_noalias, NewMD);
     } else if (NI->mayReadOrWriteMemory()) {
-      if (MDNode *M = CS.getInstruction()->getMDNode(LLVMContext::MD_noalias))
+      if (MDNode *M = CS.getInstruction()->getMetadata(LLVMContext::MD_noalias))
         NI->setMetadata(LLVMContext::MD_noalias, M);
     }
   }
@@ -589,7 +590,7 @@ static void AddAliasScopeMetadata(CallSite CS, ValueToValueMapTy &VMap,
       if (!NoAliases.empty())
         NI->setMetadata(LLVMContext::MD_noalias,
                         MDNode::concatenate(
-                            NI->getMDNode(LLVMContext::MD_noalias),
+                            NI->getMetadata(LLVMContext::MD_noalias),
                             MDNode::get(CalledFunc->getContext(), NoAliases)));
 
       // Next, we want to figure out all of the sets to which we might belong.
@@ -615,7 +616,7 @@ static void AddAliasScopeMetadata(CallSite CS, ValueToValueMapTy &VMap,
       if (!Scopes.empty())
         NI->setMetadata(
             LLVMContext::MD_alias_scope,
-            MDNode::concatenate(NI->getMDNode(LLVMContext::MD_alias_scope),
+            MDNode::concatenate(NI->getMetadata(LLVMContext::MD_alias_scope),
                                 MDNode::get(CalledFunc->getContext(), Scopes)));
     }
   }
diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp
index c6229b1028c..a2ba2b8cc06 100644
--- a/lib/Transforms/Utils/Local.cpp
+++ b/lib/Transforms/Utils/Local.cpp
@@ -128,7 +128,7 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions,
       // Check to see if this branch is going to the same place as the default
       // dest.  If so, eliminate it as an explicit compare.
       if (i.getCaseSuccessor() == DefaultDest) {
-        MDNode *MD = SI->getMDNode(LLVMContext::MD_prof);
+        MDNode *MD = SI->getMetadata(LLVMContext::MD_prof);
         unsigned NCases = SI->getNumCases();
         // Fold the case metadata into the default if there will be any branches
         // left, unless the metadata doesn't match the switch.
@@ -206,7 +206,7 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions,
       BranchInst *NewBr = Builder.CreateCondBr(Cond,
                                                FirstCase.getCaseSuccessor(),
                                                SI->getDefaultDest());
-      MDNode *MD = SI->getMDNode(LLVMContext::MD_prof);
+      MDNode *MD = SI->getMetadata(LLVMContext::MD_prof);
       if (MD && MD->getNumOperands() == 3) {
         ConstantInt *SICase = dyn_cast<ConstantInt>(MD->getOperand(2));
         ConstantInt *SIDef = dyn_cast<ConstantInt>(MD->getOperand(1));
@@ -1308,13 +1308,13 @@ bool llvm::removeUnreachableBlocks(Function &F) {
 }
 
 void llvm::combineMetadata(Instruction *K, const Instruction *J, ArrayRef<unsigned> KnownIDs) {
-  SmallVector<std::pair<unsigned, Value *>, 4> Metadata;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
   K->dropUnknownMetadata(KnownIDs);
   K->getAllMetadataOtherThanDebugLoc(Metadata);
   for (unsigned i = 0, n = Metadata.size(); i < n; ++i) {
     unsigned Kind = Metadata[i].first;
-    MDNode *JMD = J->getMDNode(Kind);
-    MDNode *KMD = cast<MDNode>(Metadata[i].second);
+    MDNode *JMD = J->getMetadata(Kind);
+    MDNode *KMD = Metadata[i].second;
 
     switch (Kind) {
       default:
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index bf7d5df3a58..6037b1ffc24 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -643,7 +643,7 @@ SimplifyEqualityComparisonWithOnlyPredecessor(TerminatorInst *TI,
 
     // Collect branch weights into a vector.
     SmallVector<uint32_t, 8> Weights;
-    MDNode *MD = SI->getMDNode(LLVMContext::MD_prof);
+    MDNode *MD = SI->getMetadata(LLVMContext::MD_prof);
     bool HasWeight = MD && (MD->getNumOperands() == 2 + SI->getNumCases());
     if (HasWeight)
       for (unsigned MD_i = 1, MD_e = MD->getNumOperands(); MD_i < MD_e;
@@ -738,7 +738,7 @@ static int ConstantIntSortPredicate(ConstantInt *const *P1,
 }
 
 static inline bool HasBranchWeights(const Instruction* I) {
-  MDNode *ProfMD = I->getMDNode(LLVMContext::MD_prof);
+  MDNode *ProfMD = I->getMetadata(LLVMContext::MD_prof);
   if (ProfMD && ProfMD->getOperand(0))
     if (MDString* MDS = dyn_cast<MDString>(ProfMD->getOperand(0)))
       return MDS->getString().equals("branch_weights");
@@ -751,7 +751,7 @@ static inline bool HasBranchWeights(const Instruction* I) {
 /// metadata.
 static void GetBranchWeights(TerminatorInst *TI,
                              SmallVectorImpl<uint64_t> &Weights) {
-  MDNode *MD = TI->getMDNode(LLVMContext::MD_prof);
+  MDNode *MD = TI->getMetadata(LLVMContext::MD_prof);
   assert(MD);
   for (unsigned i = 1, e = MD->getNumOperands(); i < e; ++i) {
     ConstantInt *CI = cast<ConstantInt>(MD->getOperand(i));
@@ -1970,7 +1970,7 @@ static bool ExtractBranchMetadata(BranchInst *BI,
                                   uint64_t &ProbTrue, uint64_t &ProbFalse) {
   assert(BI->isConditional() &&
          "Looking for probabilities on unconditional branch?");
-  MDNode *ProfileData = BI->getMDNode(LLVMContext::MD_prof);
+  MDNode *ProfileData = BI->getMetadata(LLVMContext::MD_prof);
   if (!ProfileData || ProfileData->getNumOperands() != 3) return false;
   ConstantInt *CITrue = dyn_cast<ConstantInt>(ProfileData->getOperand(1));
   ConstantInt *CIFalse = dyn_cast<ConstantInt>(ProfileData->getOperand(2));
diff --git a/lib/Transforms/Utils/ValueMapper.cpp b/lib/Transforms/Utils/ValueMapper.cpp
index 31755427d77..a2f69d1f10b 100644
--- a/lib/Transforms/Utils/ValueMapper.cpp
+++ b/lib/Transforms/Utils/ValueMapper.cpp
@@ -208,11 +208,14 @@ void llvm::RemapInstruction(Instruction *I, ValueToValueMapTy &VMap,
   }
 
   // Remap attached metadata.
-  SmallVector<std::pair<unsigned, Value *>, 4> MDs;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
   I->getAllMetadata(MDs);
-  for (auto MI = MDs.begin(), ME = MDs.end(); MI != ME; ++MI) {
-    Value *Old = MI->second;
-    Value *New = MapValue(Old, VMap, Flags, TypeMapper, Materializer);
+  for (SmallVectorImpl<std::pair<unsigned, MDNode *>>::iterator
+           MI = MDs.begin(),
+           ME = MDs.end();
+       MI != ME; ++MI) {
+    MDNode *Old = MI->second;
+    MDNode *New = MapValue(Old, VMap, Flags, TypeMapper, Materializer);
     if (New != Old)
       I->setMetadata(MI->first, New);
   }
diff --git a/lib/Transforms/Vectorize/LoopVectorize.cpp b/lib/Transforms/Vectorize/LoopVectorize.cpp
index 0a472dc7d89..20e7ce63abf 100644
--- a/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -531,7 +531,7 @@ static std::string getDebugLocString(const Loop *L) {
 
 /// \brief Propagate known metadata from one instruction to another.
 static void propagateMetadata(Instruction *To, const Instruction *From) {
-  SmallVector<std::pair<unsigned, Value *>, 4> Metadata;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
   From->getAllMetadataOtherThanDebugLoc(Metadata);
 
   for (auto M : Metadata) {
diff --git a/lib/Transforms/Vectorize/SLPVectorizer.cpp b/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 5771582896d..16ba3167e8b 100644
--- a/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -188,16 +188,16 @@ static void propagateIRFlags(Value *I, ArrayRef<Value *> VL) {
 /// \returns \p I after propagating metadata from \p VL.
 static Instruction *propagateMetadata(Instruction *I, ArrayRef<Value *> VL) {
   Instruction *I0 = cast<Instruction>(VL[0]);
-  SmallVector<std::pair<unsigned, Value *>, 4> Metadata;
+  SmallVector<std::pair<unsigned, MDNode *>, 4> Metadata;
   I0->getAllMetadataOtherThanDebugLoc(Metadata);
 
   for (unsigned i = 0, n = Metadata.size(); i != n; ++i) {
     unsigned Kind = Metadata[i].first;
-    MDNode *MD = cast_or_null<MDNode>(Metadata[i].second);
+    MDNode *MD = Metadata[i].second;
 
     for (int i = 1, e = VL.size(); MD && i != e; i++) {
       Instruction *I = cast<Instruction>(VL[i]);
-      MDNode *IMD = I->getMDNode(Kind);
+      MDNode *IMD = I->getMetadata(Kind);
 
       switch (Kind) {
       default: