This is a major cleanup of the instruction metadata interfaces that

I asked Devang to do back on Sep 27.  Instead of going through the
MetadataContext class with methods like getMD() and getMDs(), just
ask the instruction directly for its metadata with getMetadata()
and getAllMetadata().

This includes a variety of other fixes and improvements: previously
all Value*'s were bloated because the HasMetadata bit was thrown into
value, adding a 9th bit to a byte.  Now this is properly sunk down to
the Instruction class (the only place where it makes sense) and it
will be folded away somewhere soon.

This also fixes some confusion in getMDs and its clients about 
whether the returned list is indexed by the MDID or densely packed.
This is now returned sorted and densely packed and the comments make
this clear.

This introduces a number of fixme's which I'll follow up on.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92235 91177308-0d34-0410-b5e6-96231b3b80d8

15 files changed, 214 insertions, 230 deletions

diff --git a/lib/Analysis/DebugInfo.cpp b/lib/Analysis/DebugInfo.cpp
index 3732818de3..256a7d1c36 100644
--- a/lib/Analysis/DebugInfo.cpp
+++ b/lib/Analysis/DebugInfo.cpp
@@ -1117,9 +1117,7 @@ Instruction *DIFactory::InsertDbgValueIntrinsic(Value *V, Value *Offset,
 
 /// processModule - Process entire module and collect debug info.
 void DebugInfoFinder::processModule(Module &M) {
-
-  MetadataContext &TheMetadata = M.getContext().getMetadata();
-  unsigned MDDbgKind = TheMetadata.getMDKindID("dbg");
+  unsigned MDDbgKind = M.getContext().getMetadata().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)
@@ -1127,7 +1125,7 @@ void DebugInfoFinder::processModule(Module &M) {
            ++BI) {
         if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(BI))
           processDeclare(DDI);
-        else if (MDNode *L = TheMetadata.getMD(MDDbgKind, BI)) 
+        else if (MDNode *L = BI->getMetadata(MDDbgKind)) 
           processLocation(DILocation(L));
       }
 
diff --git a/lib/AsmParser/LLParser.cpp b/lib/AsmParser/LLParser.cpp
index a84336d607..d9d2a4b2ad 100644
--- a/lib/AsmParser/LLParser.cpp
+++ b/lib/AsmParser/LLParser.cpp
@@ -2826,10 +2826,9 @@ bool LLParser::ParseBasicBlock(PerFunctionState &PFS) {
       ParseOptionalCustomMetadata();
 
     // Set metadata attached with this instruction.
-    MetadataContext &TheMetadata = M->getContext().getMetadata();
     for (SmallVector<std::pair<unsigned, MDNode *>, 2>::iterator
            MDI = MDsOnInst.begin(), MDE = MDsOnInst.end(); MDI != MDE; ++MDI)
-      TheMetadata.addMD(MDI->first, MDI->second, Inst);
+      Inst->setMetadata(MDI->first, MDI->second);
     MDsOnInst.clear();
 
     BB->getInstList().push_back(Inst);
diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp
index 0bda03e337..568968d927 100644
--- a/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -18,7 +18,6 @@
 #include "llvm/InlineAsm.h"
 #include "llvm/IntrinsicInst.h"
 #include "llvm/LLVMContext.h"
-#include "llvm/Metadata.h"
 #include "llvm/Module.h"
 #include "llvm/Operator.h"
 #include "llvm/AutoUpgrade.h"
@@ -1573,7 +1572,6 @@ bool BitcodeReader::ParseMetadataAttachment() {
   if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
     return Error("Malformed block record");
 
-  MetadataContext &TheMetadata = Context.getMetadata();
   SmallVector<uint64_t, 64> Record;
   while(1) {
     unsigned Code = Stream.ReadCode();
@@ -1599,7 +1597,7 @@ bool BitcodeReader::ParseMetadataAttachment() {
       for (unsigned i = 1; i != RecordLength; i = i+2) {
         unsigned Kind = Record[i];
         Value *Node = MDValueList.getValueFwdRef(Record[i+1]);
-        TheMetadata.addMD(Kind, cast<MDNode>(Node), Inst);
+        Inst->setMetadata(Kind, cast<MDNode>(Node));
       }
       break;
     }
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index cf8f7670c7..21548cd18d 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -561,32 +561,29 @@ static void WriteMetadataAttachment(const Function &F,
 
   // Write metadata attachments
   // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
-  MetadataContext &TheMetadata = F.getContext().getMetadata();
-  typedef SmallVector<std::pair<unsigned, MDNode*>, 2> MDMapTy;
-  MDMapTy 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();
          I != E; ++I) {
       MDs.clear();
-      TheMetadata.getMDs(I, MDs);
-      bool RecordedInstruction = false;
-      for (MDMapTy::const_iterator PI = MDs.begin(), PE = MDs.end();
-             PI != PE; ++PI) {
-        if (RecordedInstruction == false) {
-          Record.push_back(VE.getInstructionID(I));
-          RecordedInstruction = true;
-        }
-        Record.push_back(PI->first);
-        Record.push_back(VE.getValueID(PI->second));
+      I->getAllMetadata(MDs);
+      
+      // If no metadata, ignore instruction.
+      if (MDs.empty()) continue;
+
+      Record.push_back(VE.getInstructionID(I));
+      
+      for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
+        Record.push_back(MDs[i].first);
+        Record.push_back(VE.getValueID(MDs[i].second));
       }
-      if (!Record.empty()) {
-        if (!StartedMetadataBlock)  {
-          Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
-          StartedMetadataBlock = true;
-        }
-        Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
-        Record.clear();
+      if (!StartedMetadataBlock)  {
+        Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
+        StartedMetadataBlock = true;
       }
+      Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
+      Record.clear();
     }
 
   if (StartedMetadataBlock)
@@ -1208,7 +1205,7 @@ static void WriteFunction(const Function &F, ValueEnumerator &VE,
     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
          I != E; ++I) {
       WriteInstruction(*I, InstID, VE, Stream, Vals);
-      if (I->getType() != Type::getVoidTy(F.getContext()))
+      if (!I->getType()->isVoidTy())
         ++InstID;
     }
 
diff --git a/lib/Bitcode/Writer/ValueEnumerator.cpp b/lib/Bitcode/Writer/ValueEnumerator.cpp
index 29c6d374da..a6da44f77a 100644
--- a/lib/Bitcode/Writer/ValueEnumerator.cpp
+++ b/lib/Bitcode/Writer/ValueEnumerator.cpp
@@ -14,8 +14,6 @@
 #include "ValueEnumerator.h"
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
-#include "llvm/LLVMContext.h"
-#include "llvm/Metadata.h"
 #include "llvm/Module.h"
 #include "llvm/TypeSymbolTable.h"
 #include "llvm/ValueSymbolTable.h"
@@ -87,9 +85,7 @@ ValueEnumerator::ValueEnumerator(const Module *M) {
          I != E; ++I)
       EnumerateType(I->getType());
 
-    MetadataContext &TheMetadata = F->getContext().getMetadata();
-    typedef SmallVector<std::pair<unsigned, MDNode*>, 2> MDMapTy;
-    MDMapTy MDs;
+    SmallVector<std::pair<unsigned, MDNode*>, 2> MDs;
     for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
       for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E;++I){
         for (User::const_op_iterator OI = I->op_begin(), E = I->op_end();
@@ -103,10 +99,9 @@ ValueEnumerator::ValueEnumerator(const Module *M) {
 
         // Enumerate metadata attached with this instruction.
         MDs.clear();
-        TheMetadata.getMDs(I, MDs);
-        for (MDMapTy::const_iterator MI = MDs.begin(), ME = MDs.end(); MI != ME;
-             ++MI)
-          EnumerateMetadata(MI->second);
+        I->getAllMetadata(MDs);
+        for (unsigned i = 0, e = MDs.size(); i != e; ++i)
+          EnumerateMetadata(MDs[i].second);
       }
   }
 
diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index 24a5b0d648..714345db2c 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -43,7 +43,6 @@
 #include "llvm/GlobalVariable.h"
 #include "llvm/Instructions.h"
 #include "llvm/IntrinsicInst.h"
-#include "llvm/LLVMContext.h"
 #include "llvm/CodeGen/FastISel.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
@@ -349,10 +348,7 @@ bool FastISel::SelectCall(User *I) {
     if (SI == StaticAllocaMap.end()) break; // VLAs.
     int FI = SI->second;
     if (MMI) {
-      MetadataContext &TheMetadata = 
-        DI->getParent()->getContext().getMetadata();
-      unsigned MDDbgKind = TheMetadata.getMDKindID("dbg");
-      if (MDNode *Dbg = TheMetadata.getMD(MDDbgKind, DI))
+      if (MDNode *Dbg = DI->getMetadata("dbg"))
         MMI->setVariableDbgInfo(DI->getVariable(), FI, Dbg);
     }
     return true;
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 266cb64b71..ec949fc27b 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -27,7 +27,6 @@
 #include "llvm/Instructions.h"
 #include "llvm/Intrinsics.h"
 #include "llvm/IntrinsicInst.h"
-#include "llvm/LLVMContext.h"
 #include "llvm/Module.h"
 #include "llvm/CodeGen/FastISel.h"
 #include "llvm/CodeGen/GCStrategy.h"
@@ -4379,14 +4378,9 @@ SelectionDAGBuilder::visitIntrinsicCall(CallInst &I, unsigned Intrinsic) {
       return 0; // VLAs.
     int FI = SI->second;
 
-    MachineModuleInfo *MMI = DAG.getMachineModuleInfo();
-    if (MMI) {
-      MetadataContext &TheMetadata = 
-        DI.getParent()->getContext().getMetadata();
-      unsigned MDDbgKind = TheMetadata.getMDKindID("dbg");
-      if (MDNode *Dbg = TheMetadata.getMD(MDDbgKind, &DI))
+    if (MachineModuleInfo *MMI = DAG.getMachineModuleInfo())
+      if (MDNode *Dbg = DI.getMetadata("dbg"))
         MMI->setVariableDbgInfo(Variable, FI, Dbg);
-    }
     return 0;
   }
   case Intrinsic::eh_exception: {
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 7efd480dcc..a46aad7e48 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -362,12 +362,12 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
 
 /// SetDebugLoc - Update MF's and SDB's DebugLocs if debug information is
 /// attached with this instruction.
-static void SetDebugLoc(unsigned MDDbgKind, MetadataContext &TheMetadata,
-                        Instruction *I, SelectionDAGBuilder *SDB,
+static void SetDebugLoc(unsigned MDDbgKind, Instruction *I,
+                        SelectionDAGBuilder *SDB,
                         FastISel *FastIS, MachineFunction *MF) {
   if (isa<DbgInfoIntrinsic>(I)) return;
   
-  if (MDNode *Dbg = TheMetadata.getMD(MDDbgKind, I)) {
+  if (MDNode *Dbg = I->getMetadata(MDDbgKind)) {
     DILocation DILoc(Dbg);
     DebugLoc Loc = ExtractDebugLocation(DILoc, MF->getDebugLocInfo());
 
@@ -384,8 +384,7 @@ static void SetDebugLoc(unsigned MDDbgKind, MetadataContext &TheMetadata,
 }
 
 /// ResetDebugLoc - Set MF's and SDB's DebugLocs to Unknown.
-static void ResetDebugLoc(SelectionDAGBuilder *SDB,
-                          FastISel *FastIS) {
+static void ResetDebugLoc(SelectionDAGBuilder *SDB, FastISel *FastIS) {
   SDB->setCurDebugLoc(DebugLoc::getUnknownLoc());
   if (FastIS)
     FastIS->setCurDebugLoc(DebugLoc::getUnknownLoc());
@@ -402,7 +401,7 @@ void SelectionDAGISel::SelectBasicBlock(BasicBlock *LLVMBB,
   // Lower all of the non-terminator instructions. If a call is emitted
   // as a tail call, cease emitting nodes for this block.
   for (BasicBlock::iterator I = Begin; I != End && !SDB->HasTailCall; ++I) {
-    SetDebugLoc(MDDbgKind, TheMetadata, I, SDB, 0, MF);
+    SetDebugLoc(MDDbgKind, I, SDB, 0, MF);
 
     if (!isa<TerminatorInst>(I)) {
       SDB->visit(*I);
@@ -425,7 +424,7 @@ void SelectionDAGISel::SelectBasicBlock(BasicBlock *LLVMBB,
       HandlePHINodesInSuccessorBlocks(LLVMBB);
 
       // Lower the terminator after the copies are emitted.
-      SetDebugLoc(MDDbgKind, TheMetadata, LLVMBB->getTerminator(), SDB, 0, MF);
+      SetDebugLoc(MDDbgKind, LLVMBB->getTerminator(), SDB, 0, MF);
       SDB->visit(*LLVMBB->getTerminator());
       ResetDebugLoc(SDB, 0);
     }
@@ -776,7 +775,7 @@ void SelectionDAGISel::SelectAllBasicBlocks(Function &Fn,
             break;
           }
 
-        SetDebugLoc(MDDbgKind, TheMetadata, BI, SDB, FastIS, &MF);
+        SetDebugLoc(MDDbgKind, BI, SDB, FastIS, &MF);
 
         // First try normal tablegen-generated "fast" selection.
         if (FastIS->SelectInstruction(BI)) {
diff --git a/lib/Transforms/IPO/StripSymbols.cpp b/lib/Transforms/IPO/StripSymbols.cpp
index b213b014eb..0d756267cf 100644
--- a/lib/Transforms/IPO/StripSymbols.cpp
+++ b/lib/Transforms/IPO/StripSymbols.cpp
@@ -228,7 +228,7 @@ static bool StripDebugInfo(Module &M) {
          ++FI)
       for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); BI != BE;
            ++BI) 
-        TheMetadata.removeMD(MDDbgKind, BI);
+        BI->setMetadata(MDDbgKind, 0);
 
   return true;
 }
diff --git a/lib/Transforms/Utils/CloneFunction.cpp b/lib/Transforms/Utils/CloneFunction.cpp
index 2f94ee16cb..995d6e4baa 100644
--- a/lib/Transforms/Utils/CloneFunction.cpp
+++ b/lib/Transforms/Utils/CloneFunction.cpp
@@ -426,7 +426,7 @@ void llvm::CloneAndPruneFunctionInto(Function *NewFunc, const Function *OldFunc,
     MDNode *TheCallMD = NULL;
     SmallVector<Value *, 4> MDVs;
     if (TheCall && TheCall->hasMetadata()) 
-      TheCallMD = Context.getMetadata().getMD(DbgKind, TheCall);
+      TheCallMD = TheCall->getMetadata(DbgKind);
     
     // Handle PHI nodes specially, as we have to remove references to dead
     // blocks.
@@ -436,32 +436,38 @@ void llvm::CloneAndPruneFunctionInto(Function *NewFunc, const Function *OldFunc,
       for (; (PN = dyn_cast<PHINode>(I)); ++I, ++OldI) {
         if (I->hasMetadata()) {
           if (TheCallMD) {
-            if (MDNode *IMD = Context.getMetadata().getMD(DbgKind, I)) {
+            if (MDNode *IMD = I->getMetadata(DbgKind)) {
               MDNode *NewMD = UpdateInlinedAtInfo(IMD, TheCallMD, Context);
-              Context.getMetadata().addMD(DbgKind, NewMD, I);
+              I->setMetadata(DbgKind, NewMD);
             }
           } else {
             // The cloned instruction has dbg info but the call instruction
             // does not have dbg info. Remove dbg info from cloned instruction.
-            Context.getMetadata().removeMD(DbgKind, I);
+            I->setMetadata(DbgKind, 0);
           }
         }
         PHIToResolve.push_back(cast<PHINode>(OldI));
       }
     }
     
+    // FIXME:
+    // FIXME:
+    // FIXME: Unclone all this metadata stuff.
+    // FIXME:
+    // FIXME:
+    
     // Otherwise, remap the rest of the instructions normally.
     for (; I != NewBB->end(); ++I) {
       if (I->hasMetadata()) {
         if (TheCallMD) {
-          if (MDNode *IMD = Context.getMetadata().getMD(DbgKind, I)) {
+          if (MDNode *IMD = I->getMetadata(DbgKind)) {
             MDNode *NewMD = UpdateInlinedAtInfo(IMD, TheCallMD, Context);
-            Context.getMetadata().addMD(DbgKind, NewMD, I);
+            I->setMetadata(DbgKind, NewMD);
           }
         } else {
           // The cloned instruction has dbg info but the call instruction
           // does not have dbg info. Remove dbg info from cloned instruction.
-          Context.getMetadata().removeMD(DbgKind, I);
+          I->setMetadata(DbgKind, 0);
         }
       }
       RemapInstruction(I, ValueMap);
diff --git a/lib/VMCore/AsmWriter.cpp b/lib/VMCore/AsmWriter.cpp
index c9c9bf0fe9..824eac0902 100644
--- a/lib/VMCore/AsmWriter.cpp
+++ b/lib/VMCore/AsmWriter.cpp
@@ -21,11 +21,9 @@
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/InlineAsm.h"
-#include "llvm/Instruction.h"
-#include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
 #include "llvm/LLVMContext.h"
 #include "llvm/Operator.h"
-#include "llvm/Metadata.h"
 #include "llvm/Module.h"
 #include "llvm/ValueSymbolTable.h"
 #include "llvm/TypeSymbolTable.h"
@@ -680,30 +678,30 @@ void SlotTracker::processFunction() {
 
   ST_DEBUG("Inserting Instructions:\n");
 
-  MetadataContext &TheMetadata = TheFunction->getContext().getMetadata();
-  typedef SmallVector<std::pair<unsigned, MDNode*>, 2> MDMapTy;
-  MDMapTy MDs;
+  SmallVector<std::pair<unsigned, MDNode*>, 2> MDForInst;
 
   // Add all of the basic blocks and instructions with no names.
   for (Function::const_iterator BB = TheFunction->begin(),
        E = TheFunction->end(); BB != E; ++BB) {
     if (!BB->hasName())
       CreateFunctionSlot(BB);
+    
     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E;
          ++I) {
-      if (I->getType() != Type::getVoidTy(TheFunction->getContext()) &&
-          !I->hasName())
+      if (!I->getType()->isVoidTy() && !I->hasName())
         CreateFunctionSlot(I);
-      for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
-        if (MDNode *N = dyn_cast_or_null<MDNode>(I->getOperand(i)))
-          CreateMetadataSlot(N);
+      
+      // Intrinsics can directly use metadata.
+      if (isa<IntrinsicInst>(I))
+        for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
+          if (MDNode *N = dyn_cast_or_null<MDNode>(I->getOperand(i)))
+            CreateMetadataSlot(N);
 
       // Process metadata attached with this instruction.
-      MDs.clear();
-      TheMetadata.getMDs(I, MDs);
-      for (MDMapTy::const_iterator MI = MDs.begin(), ME = MDs.end(); MI != ME; 
-           ++MI)
-        CreateMetadataSlot(MI->second);
+      MDForInst.clear();
+      I->getAllMetadata(MDForInst);
+      for (unsigned i = 0, e = MDForInst.size(); i != e; ++i)
+        CreateMetadataSlot(MDForInst[i].second);
     }
   }
 
@@ -2076,14 +2074,11 @@ void AssemblyWriter::printInstruction(const Instruction &I) {
 
   // Print Metadata info.
   if (!MDNames.empty()) {
-    MetadataContext &TheMetadata = I.getContext().getMetadata();
-    typedef SmallVector<std::pair<unsigned, MDNode*>, 2> MDMapTy;
-    MDMapTy MDs;
-    TheMetadata.getMDs(&I, MDs);
-    for (MDMapTy::const_iterator MI = MDs.begin(), ME = MDs.end(); MI != ME; 
-         ++MI)
-      Out << ", !" << MDNames[MI->first]
-          << " !" << Machine.getMetadataSlot(MI->second);
+    SmallVector<std::pair<unsigned, MDNode*>, 4> InstMD;
+    I.getAllMetadata(InstMD);
+    for (unsigned i = 0, e = InstMD.size(); i != e; ++i)
+      Out << ", !" << MDNames[InstMD[i].first]
+          << " !" << Machine.getMetadataSlot(InstMD[i].second);
   }
   printInfoComment(I);
 }
diff --git a/lib/VMCore/IRBuilder.cpp b/lib/VMCore/IRBuilder.cpp
index 0b4a10925a..4c0299c6fc 100644
--- a/lib/VMCore/IRBuilder.cpp
+++ b/lib/VMCore/IRBuilder.cpp
@@ -43,7 +43,7 @@ void IRBuilderBase::SetCurrentDebugLocation(MDNode *L) {
 
 void IRBuilderBase::SetInstDebugLocation(Instruction *I) const {
   if (CurDbgLocation)
-    Context.getMetadata().addMD(DbgMDKind, CurDbgLocation, I);
+    I->setMetadata(DbgMDKind, CurDbgLocation);
 }
 
 const Type *IRBuilderBase::getCurrentFunctionReturnType() const {
diff --git a/lib/VMCore/Instruction.cpp b/lib/VMCore/Instruction.cpp
index ce253d64ce..f468c1bf3a 100644
--- a/lib/VMCore/Instruction.cpp
+++ b/lib/VMCore/Instruction.cpp
@@ -24,7 +24,8 @@ using namespace llvm;
 
 Instruction::Instruction(const Type *ty, unsigned it, Use *Ops, unsigned NumOps,
                          Instruction *InsertBefore)
-  : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0) {
+  : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0),
+    HasMetadata(false) {
   // Make sure that we get added to a basicblock
   LeakDetector::addGarbageObject(this);
 
@@ -38,7 +39,8 @@ Instruction::Instruction(const Type *ty, unsigned it, Use *Ops, unsigned NumOps,
 
 Instruction::Instruction(const Type *ty, unsigned it, Use *Ops, unsigned NumOps,
                          BasicBlock *InsertAtEnd)
-  : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0) {
+  : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(0),
+    HasMetadata(false) {
   // Make sure that we get added to a basicblock
   LeakDetector::addGarbageObject(this);
 
@@ -51,10 +53,8 @@ Instruction::Instruction(const Type *ty, unsigned it, Use *Ops, unsigned NumOps,
 // Out of line virtual method, so the vtable, etc has a home.
 Instruction::~Instruction() {
   assert(Parent == 0 && "Instruction still linked in the program!");
-  if (hasMetadata()) {
-    LLVMContext &Context = getContext();
-    Context.pImpl->TheMetadata.ValueIsDeleted(this);
-  }
+  if (HasMetadata)
+    getContext().pImpl->TheMetadata.ValueIsDeleted(this);
 }
 
 
@@ -464,7 +464,7 @@ bool Instruction::isSafeToSpeculativelyExecute() const {
 Instruction *Instruction::clone() const {
   Instruction *New = clone_impl();
   New->SubclassOptionalData = SubclassOptionalData;
-  if (hasMetadata())
+  if (HasMetadata)
     getContext().pImpl->TheMetadata.ValueIsCloned(this, New);
   return New;
 }
diff --git a/lib/VMCore/Metadata.cpp b/lib/VMCore/Metadata.cpp
index a516d7bf93..1374754731 100644
--- a/lib/VMCore/Metadata.cpp
+++ b/lib/VMCore/Metadata.cpp
@@ -261,32 +261,27 @@ private:
   StringMap<unsigned> MDHandlerNames;
 
 public:
+  // Name <-> ID mapping methods.
   unsigned getMDKindID(StringRef Name);
-
-  /// getMD - Get the metadata of given kind attached to an Instruction.
-  /// If the metadata is not found then return 0.
-  MDNode *getMD(unsigned Kind, const Instruction *Inst);
-
-  /// getMDs - Get the metadata attached to an Instruction.
-  void getMDs(const Instruction *Inst,
-              SmallVectorImpl<std::pair<unsigned, MDNode*> > &MDs) const;
-
-  /// addMD - Attach the metadata of given kind to an Instruction.
-  void addMD(unsigned Kind, MDNode *Node, Instruction *Inst);
+  void getMDKindNames(SmallVectorImpl<StringRef> &) const;
   
-  /// removeMD - Remove metadata of given kind attached with an instruction.
-  void removeMD(unsigned Kind, Instruction *Inst);
   
+  // 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 with an instruction.
   void removeAllMetadata(Instruction *Inst);
-
+  
+  
+  
   /// copyMD - If metadata is attached with Instruction In1 then attach
   /// the same metadata to In2.
   void copyMD(Instruction *In1, Instruction *In2);
-
-  /// getMDKindNames - Populate client-supplied smallvector using custom
-  /// metadata name and ID.
-  void getMDKindNames(SmallVectorImpl<StringRef> &) const;
+  
 
   /// ValueIsDeleted - This handler is used to update metadata store
   /// when a value is deleted.
@@ -308,49 +303,96 @@ unsigned MetadataContextImpl::getMDKindID(StringRef Name) {
 
   // If this is new, assign it its ID.
   if (Entry == 0) Entry = MDHandlerNames.size();
-  
   return Entry;
 }
 
-/// addMD - Attach the metadata of given kind to an Instruction.
-void MetadataContextImpl::addMD(unsigned MDKind, MDNode *Node, 
-                                Instruction *Inst) {
-  assert(Node && "Invalid null MDNode");
-  Inst->HasMetadata = true;
-  MDMapTy &Info = MetadataStore[Inst];
-  if (Info.empty()) {
-    Info.push_back(std::make_pair(MDKind, Node));
-    MetadataStore.insert(std::make_pair(Inst, Info));
-    return;
-  }
+/// 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();
+}
 
-  // If there is an entry for this MDKind then replace it.
-  for (unsigned i = 0, e = Info.size(); i != e; ++i) {
-    MDPairTy &P = Info[i];
-    if (P.first == MDKind) {
-      Info[i] = std::make_pair(MDKind, Node);
-      return;
-    }
-  }
 
-  // Otherwise add a new entry.
-  Info.push_back(std::make_pair(MDKind, Node));
+/// 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;
 }
 
-/// removeMD - Remove metadata of given kind attached with an instruction.
-void MetadataContextImpl::removeMD(unsigned Kind, Instruction *Inst) {
-  MDStoreTy::iterator I = MetadataStore.find(Inst);
-  if (I == MetadataStore.end())
+/// 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->HasMetadata = 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];
 
-  MDMapTy &Info = I->second;
-  for (MDMapTy::iterator MI = Info.begin(), ME = Info.end(); MI != ME; ++MI) {
-    MDPairTy &P = *MI;
-    if (P.first == Kind) {
-      Info.erase(MI);
+  // Common case is removing the only entry.
+  if (Info.size() == 1 && Info[0].first == Kind) {
+    MetadataStore.erase(Inst);
+    Inst->HasMetadata = 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.
@@ -359,6 +401,7 @@ void MetadataContextImpl::removeAllMetadata(Instruction *Inst) {
   Inst->HasMetadata = false;
 }
 
+
 /// copyMD - If metadata is attached with Instruction In1 then attach
 /// the same metadata to In2.
 void MetadataContextImpl::copyMD(Instruction *In1, Instruction *In2) {
@@ -366,48 +409,9 @@ void MetadataContextImpl::copyMD(Instruction *In1, Instruction *In2) {
   MDMapTy &In1Info = MetadataStore[In1];
   if (In1Info.empty())
     return;
-
+  
   for (MDMapTy::iterator I = In1Info.begin(), E = In1Info.end(); I != E; ++I)
-    addMD(I->first, I->second, In2);
-}
-
-/// getMD - Get the metadata of given kind attached to an Instruction.
-/// If the metadata is not found then return 0.
-MDNode *MetadataContextImpl::getMD(unsigned MDKind, const Instruction *Inst) {
-  MDMapTy &Info = MetadataStore[Inst];
-  if (Info.empty())
-    return NULL;
-
-  for (MDMapTy::iterator I = Info.begin(), E = Info.end(); I != E; ++I)
-    if (I->first == MDKind)
-      return I->second;
-  return NULL;
-}
-
-/// getMDs - Get the metadata attached to an Instruction.
-void MetadataContextImpl::
-getMDs(const Instruction *Inst,
-       SmallVectorImpl<std::pair<unsigned, MDNode*> > &MDs) const {
-  MDStoreTy::const_iterator I = MetadataStore.find(Inst);
-  if (I == MetadataStore.end())
-    return;
-  MDs.resize(I->second.size());
-  for (MDMapTy::const_iterator MI = I->second.begin(), ME = I->second.end();
-       MI != ME; ++MI)
-    // MD kinds are numbered from 1.
-    MDs[MI->first - 1] = std::make_pair(MI->first, MI->second);
-}
-
-/// 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();
+    In2->setMetadata(I->first, I->second);
 }
 
 /// ValueIsCloned - This handler is used to update metadata store
@@ -421,7 +425,7 @@ void MetadataContextImpl::ValueIsCloned(const Instruction *In1,
   // FIXME: Give all metadata handlers a chance to adjust.
   MDMapTy &In1Info = I->second;
   for (MDMapTy::iterator I = In1Info.begin(), E = In1Info.end(); I != E; ++I)
-    addMD(I->first, I->second, In2);
+    In2->setMetadata(I->first, I->second);
 }
 
 /// ValueIsRAUWd - This handler is used when V1's all uses are replaced by
@@ -463,34 +467,6 @@ unsigned MetadataContext::getMDKindID(StringRef Name) const {
   return pImpl->getMDKindID(Name);
 }
 
-/// getMD - Get the metadata of given kind attached to an Instruction.
-/// If the metadata is not found then return 0.
-MDNode *MetadataContext::getMD(unsigned Kind, const Instruction *Inst) {
-  return pImpl->getMD(Kind, Inst);
-}
-
-/// getMDs - Get the metadata attached to an Instruction.
-void MetadataContext::
-getMDs(const Instruction *Inst, 
-       SmallVectorImpl<std::pair<unsigned, MDNode*> > &MDs) const {
-  return pImpl->getMDs(Inst, MDs);
-}
-
-/// addMD - Attach the metadata of given kind to an Instruction.
-void MetadataContext::addMD(unsigned Kind, MDNode *Node, Instruction *Inst) {
-  pImpl->addMD(Kind, Node, Inst);
-}
-
-/// removeMD - Remove metadata of given kind attached with an instruction.
-void MetadataContext::removeMD(unsigned Kind, Instruction *Inst) {
-  pImpl->removeMD(Kind, Inst);
-}
-
-/// removeAllMetadata - Remove all metadata attached with an instruction.
-void MetadataContext::removeAllMetadata(Instruction *Inst) {
-  pImpl->removeAllMetadata(Inst);
-}
-
 /// copyMD - If metadata is attached with Instruction In1 then attach
 /// the same metadata to In2.
 void MetadataContext::copyMD(Instruction *In1, Instruction *In2) {
@@ -517,3 +493,35 @@ void MetadataContext::ValueIsRAUWd(Value *V1, Value *V2) {
 void MetadataContext::ValueIsCloned(const Instruction *In1, Instruction *In2) {
   pImpl->ValueIsCloned(In1, In2);
 }
+
+//===----------------------------------------------------------------------===//
+// Instruction Metadata method implementations.
+//
+
+void Instruction::setMetadata(const char *Kind, MDNode *Node) {
+  if (Node == 0 && !hasMetadata()) return;
+  setMetadata(getContext().getMetadata().getMDKindID(Kind), Node);
+}
+
+MDNode *Instruction::getMetadataImpl(const char *Kind) const {
+  return getMetadataImpl(getContext().getMetadata().getMDKindID(Kind));
+}
+
+/// setMetadata - Set the metadata of of the specified kind to the specified
+/// node.  This updates/replaces metadata if already present, or removes it if
+/// Node is null.
+void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
+  if (Node == 0 && !hasMetadata()) return;
+  
+  getContext().getMetadata().pImpl->setMetadata(this, KindID, Node);
+}
+
+MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
+  return getContext().getMetadata().pImpl->getMetadata(this, KindID);
+}
+
+void Instruction::getAllMetadataImpl(SmallVectorImpl<std::pair<unsigned,
+                                       MDNode*> > &Result)const {
+  getContext().getMetadata().pImpl->getAllMetadata(this, Result);
+}
+
diff --git a/lib/VMCore/Value.cpp b/lib/VMCore/Value.cpp
index 826e8a10b5..0155fa5cfe 100644
--- a/lib/VMCore/Value.cpp
+++ b/lib/VMCore/Value.cpp
@@ -41,7 +41,7 @@ static inline const Type *checkType(const Type *Ty) {
 }
 
 Value::Value(const Type *ty, unsigned scid)
-  : SubclassID(scid), HasValueHandle(0), HasMetadata(0),
+  : SubclassID(scid), HasValueHandle(0),
     SubclassOptionalData(0), SubclassData(0), VTy(checkType(ty)),
     UseList(0), Name(0) {
   if (isa<CallInst>(this) || isa<InvokeInst>(this))
@@ -57,11 +57,6 @@ Value::Value(const Type *ty, unsigned scid)
 }
 
 Value::~Value() {
-  if (HasMetadata) {
-    LLVMContext &Context = getContext();
-    Context.pImpl->TheMetadata.ValueIsDeleted(this);
-  }
-
   // Notify all ValueHandles (if present) that this value is going away.
   if (HasValueHandle)
     ValueHandleBase::ValueIsDeleted(this);
@@ -306,10 +301,14 @@ void Value::uncheckedReplaceAllUsesWith(Value *New) {
   // Notify all ValueHandles (if present) that this value is going away.
   if (HasValueHandle)
     ValueHandleBase::ValueIsRAUWd(this, New);
-  if (HasMetadata) {
-    LLVMContext &Context = getContext();
-    Context.pImpl->TheMetadata.ValueIsRAUWd(this, New);
-  }
+
+  // FIXME: It doesn't make sense at all for metadata to follow RAUW.
+  if (Instruction *I = dyn_cast<Instruction>(this))
+    if (I->hasMetadata()) {
+      LLVMContext &Context = getContext();
+      // FIXME: NUKE ValueIsRAUWd??
+      Context.pImpl->TheMetadata.ValueIsRAUWd(this, New);
+    }
 
   while (!use_empty()) {
     Use &U = *UseList;