Update aosp/master LLVM for rebase to r230699.

Change-Id: I2b5be30509658cb8266be782de0ab24f9099f9b9

4 files changed, 697 insertions, 221 deletions

diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index 6cfc357..ecb6f7c 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -17,6 +17,7 @@
 #include "llvm/Bitcode/BitstreamWriter.h"
 #include "llvm/Bitcode/LLVMBitCodes.h"
 #include "llvm/IR/Constants.h"
+#include "llvm/IR/DebugInfoMetadata.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/InlineAsm.h"
 #include "llvm/IR/Instructions.h"
@@ -55,7 +56,8 @@ enum {
   FUNCTION_INST_CAST_ABBREV,
   FUNCTION_INST_RET_VOID_ABBREV,
   FUNCTION_INST_RET_VAL_ABBREV,
-  FUNCTION_INST_UNREACHABLE_ABBREV
+  FUNCTION_INST_UNREACHABLE_ABBREV,
+  FUNCTION_INST_GEP_ABBREV,
 };
 
 static unsigned GetEncodedCastOpcode(unsigned Opcode) {
@@ -322,7 +324,7 @@ static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) {
   Stream.EnterSubblock(bitc::TYPE_BLOCK_ID_NEW, 4 /*count from # abbrevs */);
   SmallVector<uint64_t, 64> TypeVals;
 
-  uint64_t NumBits = Log2_32_Ceil(VE.getTypes().size()+1);
+  uint64_t NumBits = VE.computeBitsRequiredForTypeIndicies();
 
   // Abbrev for TYPE_CODE_POINTER.
   BitCodeAbbrev *Abbv = new BitCodeAbbrev();
@@ -477,17 +479,28 @@ static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) {
 
 static unsigned getEncodedLinkage(const GlobalValue &GV) {
   switch (GV.getLinkage()) {
-  case GlobalValue::ExternalLinkage:                 return 0;
-  case GlobalValue::WeakAnyLinkage:                  return 1;
-  case GlobalValue::AppendingLinkage:                return 2;
-  case GlobalValue::InternalLinkage:                 return 3;
-  case GlobalValue::LinkOnceAnyLinkage:              return 4;
-  case GlobalValue::ExternalWeakLinkage:             return 7;
-  case GlobalValue::CommonLinkage:                   return 8;
-  case GlobalValue::PrivateLinkage:                  return 9;
-  case GlobalValue::WeakODRLinkage:                  return 10;
-  case GlobalValue::LinkOnceODRLinkage:              return 11;
-  case GlobalValue::AvailableExternallyLinkage:      return 12;
+  case GlobalValue::ExternalLinkage:
+    return 0;
+  case GlobalValue::WeakAnyLinkage:
+    return 16;
+  case GlobalValue::AppendingLinkage:
+    return 2;
+  case GlobalValue::InternalLinkage:
+    return 3;
+  case GlobalValue::LinkOnceAnyLinkage:
+    return 18;
+  case GlobalValue::ExternalWeakLinkage:
+    return 7;
+  case GlobalValue::CommonLinkage:
+    return 8;
+  case GlobalValue::PrivateLinkage:
+    return 9;
+  case GlobalValue::WeakODRLinkage:
+    return 17;
+  case GlobalValue::LinkOnceODRLinkage:
+    return 19;
+  case GlobalValue::AvailableExternallyLinkage:
+    return 12;
   }
   llvm_unreachable("Invalid linkage");
 }
@@ -538,11 +551,13 @@ static unsigned getEncodedComdatSelectionKind(const Comdat &C) {
 }
 
 static void writeComdats(const ValueEnumerator &VE, BitstreamWriter &Stream) {
-  SmallVector<uint8_t, 64> Vals;
+  SmallVector<uint16_t, 64> Vals;
   for (const Comdat *C : VE.getComdats()) {
     // COMDAT: [selection_kind, name]
     Vals.push_back(getEncodedComdatSelectionKind(*C));
-    Vals.push_back(C->getName().size());
+    size_t Size = C->getName().size();
+    assert(isUInt<16>(Size));
+    Vals.push_back(Size);
     for (char Chr : C->getName())
       Vals.push_back((unsigned char)Chr);
     Stream.EmitRecord(bitc::MODULE_CODE_COMDAT, Vals, /*AbbrevToUse=*/0);
@@ -616,7 +631,7 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
                               Log2_32_Ceil(MaxGlobalType+1)));
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));      // Constant.
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));        // Initializer.
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));      // Linkage.
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5));      // Linkage.
     if (MaxAlignment == 0)                                      // Alignment.
       Abbv->Add(BitCodeAbbrevOp(0));
     else {
@@ -640,7 +655,8 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
 
     // GLOBALVAR: [type, isconst, initid,
     //             linkage, alignment, section, visibility, threadlocal,
-    //             unnamed_addr, externally_initialized, dllstorageclass]
+    //             unnamed_addr, externally_initialized, dllstorageclass,
+    //             comdat]
     Vals.push_back(VE.getTypeID(GV.getType()));
     Vals.push_back(GV.isConstant());
     Vals.push_back(GV.isDeclaration() ? 0 :
@@ -670,7 +686,8 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   // Emit the function proto information.
   for (const Function &F : *M) {
     // FUNCTION:  [type, callingconv, isproto, linkage, paramattrs, alignment,
-    //             section, visibility, gc, unnamed_addr, prefix]
+    //             section, visibility, gc, unnamed_addr, prologuedata,
+    //             dllstorageclass, comdat, prefixdata]
     Vals.push_back(VE.getTypeID(F.getType()));
     Vals.push_back(F.getCallingConv());
     Vals.push_back(F.isDeclaration());
@@ -681,10 +698,12 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
     Vals.push_back(getEncodedVisibility(F));
     Vals.push_back(F.hasGC() ? GCMap[F.getGC()] : 0);
     Vals.push_back(F.hasUnnamedAddr());
-    Vals.push_back(F.hasPrefixData() ? (VE.getValueID(F.getPrefixData()) + 1)
-                                      : 0);
+    Vals.push_back(F.hasPrologueData() ? (VE.getValueID(F.getPrologueData()) + 1)
+                                       : 0);
     Vals.push_back(getEncodedDLLStorageClass(F));
     Vals.push_back(F.hasComdat() ? VE.getComdatID(F.getComdat()) : 0);
+    Vals.push_back(F.hasPrefixData() ? (VE.getValueID(F.getPrefixData()) + 1)
+                                     : 0);
 
     unsigned AbbrevToUse = 0;
     Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
@@ -734,89 +753,497 @@ static uint64_t GetOptimizationFlags(const Value *V) {
   return Flags;
 }
 
-static void WriteMDNode(const MDNode *N,
-                        const ValueEnumerator &VE,
-                        BitstreamWriter &Stream,
-                        SmallVectorImpl<uint64_t> &Record) {
+static void WriteValueAsMetadata(const ValueAsMetadata *MD,
+                                 const ValueEnumerator &VE,
+                                 BitstreamWriter &Stream,
+                                 SmallVectorImpl<uint64_t> &Record) {
+  // Mimic an MDNode with a value as one operand.
+  Value *V = MD->getValue();
+  Record.push_back(VE.getTypeID(V->getType()));
+  Record.push_back(VE.getValueID(V));
+  Stream.EmitRecord(bitc::METADATA_VALUE, Record, 0);
+  Record.clear();
+}
+
+static void WriteMDTuple(const MDTuple *N, const ValueEnumerator &VE,
+                         BitstreamWriter &Stream,
+                         SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
-    if (N->getOperand(i)) {
-      Record.push_back(VE.getTypeID(N->getOperand(i)->getType()));
-      Record.push_back(VE.getValueID(N->getOperand(i)));
-    } else {
-      Record.push_back(VE.getTypeID(Type::getVoidTy(N->getContext())));
-      Record.push_back(0);
-    }
+    Metadata *MD = N->getOperand(i);
+    assert(!(MD && isa<LocalAsMetadata>(MD)) &&
+           "Unexpected function-local metadata");
+    Record.push_back(VE.getMetadataOrNullID(MD));
   }
-  unsigned MDCode = N->isFunctionLocal() ? bitc::METADATA_FN_NODE :
-                                           bitc::METADATA_NODE;
-  Stream.EmitRecord(MDCode, Record, 0);
+  Stream.EmitRecord(N->isDistinct() ? bitc::METADATA_DISTINCT_NODE
+                                    : bitc::METADATA_NODE,
+                    Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDLocation(const MDLocation *N, const ValueEnumerator &VE,
+                            BitstreamWriter &Stream,
+                            SmallVectorImpl<uint64_t> &Record,
+                            unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getLine());
+  Record.push_back(N->getColumn());
+  Record.push_back(VE.getMetadataID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getInlinedAt()));
+
+  Stream.EmitRecord(bitc::METADATA_LOCATION, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteGenericDebugNode(const GenericDebugNode *N,
+                                  const ValueEnumerator &VE,
+                                  BitstreamWriter &Stream,
+                                  SmallVectorImpl<uint64_t> &Record,
+                                  unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getTag());
+  Record.push_back(0); // Per-tag version field; unused for now.
+
+  for (auto &I : N->operands())
+    Record.push_back(VE.getMetadataOrNullID(I));
+
+  Stream.EmitRecord(bitc::METADATA_GENERIC_DEBUG, Record, Abbrev);
+  Record.clear();
+}
+
+static uint64_t rotateSign(int64_t I) {
+  uint64_t U = I;
+  return I < 0 ? ~(U << 1) : U << 1;
+}
+
+static void WriteMDSubrange(const MDSubrange *N, const ValueEnumerator &,
+                            BitstreamWriter &Stream,
+                            SmallVectorImpl<uint64_t> &Record,
+                            unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getCount());
+  Record.push_back(rotateSign(N->getLo()));
+
+  Stream.EmitRecord(bitc::METADATA_SUBRANGE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDEnumerator(const MDEnumerator *N, const ValueEnumerator &VE,
+                              BitstreamWriter &Stream,
+                              SmallVectorImpl<uint64_t> &Record,
+                              unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(rotateSign(N->getValue()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+
+  Stream.EmitRecord(bitc::METADATA_ENUMERATOR, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDBasicType(const MDBasicType *N, const ValueEnumerator &VE,
+                             BitstreamWriter &Stream,
+                             SmallVectorImpl<uint64_t> &Record,
+                             unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getTag());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(N->getSizeInBits());
+  Record.push_back(N->getAlignInBits());
+  Record.push_back(N->getEncoding());
+
+  Stream.EmitRecord(bitc::METADATA_BASIC_TYPE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDDerivedType(const MDDerivedType *N,
+                               const ValueEnumerator &VE,
+                               BitstreamWriter &Stream,
+                               SmallVectorImpl<uint64_t> &Record,
+                               unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getTag());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(N->getLine());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getBaseType()));
+  Record.push_back(N->getSizeInBits());
+  Record.push_back(N->getAlignInBits());
+  Record.push_back(N->getOffsetInBits());
+  Record.push_back(N->getFlags());
+  Record.push_back(VE.getMetadataOrNullID(N->getExtraData()));
+
+  Stream.EmitRecord(bitc::METADATA_DERIVED_TYPE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDCompositeType(const MDCompositeType *N,
+                                 const ValueEnumerator &VE,
+                                 BitstreamWriter &Stream,
+                                 SmallVectorImpl<uint64_t> &Record,
+                                 unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getTag());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(N->getLine());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getBaseType()));
+  Record.push_back(N->getSizeInBits());
+  Record.push_back(N->getAlignInBits());
+  Record.push_back(N->getOffsetInBits());
+  Record.push_back(N->getFlags());
+  Record.push_back(VE.getMetadataOrNullID(N->getElements()));
+  Record.push_back(N->getRuntimeLang());
+  Record.push_back(VE.getMetadataOrNullID(N->getVTableHolder()));
+  Record.push_back(VE.getMetadataOrNullID(N->getTemplateParams()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawIdentifier()));
+
+  Stream.EmitRecord(bitc::METADATA_COMPOSITE_TYPE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDSubroutineType(const MDSubroutineType *N,
+                                  const ValueEnumerator &VE,
+                                  BitstreamWriter &Stream,
+                                  SmallVectorImpl<uint64_t> &Record,
+                                  unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getFlags());
+  Record.push_back(VE.getMetadataOrNullID(N->getTypeArray()));
+
+  Stream.EmitRecord(bitc::METADATA_SUBROUTINE_TYPE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDFile(const MDFile *N, const ValueEnumerator &VE,
+                        BitstreamWriter &Stream,
+                        SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawFilename()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawDirectory()));
+
+  Stream.EmitRecord(bitc::METADATA_FILE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDCompileUnit(const MDCompileUnit *N,
+                               const ValueEnumerator &VE,
+                               BitstreamWriter &Stream,
+                               SmallVectorImpl<uint64_t> &Record,
+                               unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getSourceLanguage());
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawProducer()));
+  Record.push_back(N->isOptimized());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawFlags()));
+  Record.push_back(N->getRuntimeVersion());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawSplitDebugFilename()));
+  Record.push_back(N->getEmissionKind());
+  Record.push_back(VE.getMetadataOrNullID(N->getEnumTypes()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRetainedTypes()));
+  Record.push_back(VE.getMetadataOrNullID(N->getSubprograms()));
+  Record.push_back(VE.getMetadataOrNullID(N->getGlobalVariables()));
+  Record.push_back(VE.getMetadataOrNullID(N->getImportedEntities()));
+
+  Stream.EmitRecord(bitc::METADATA_COMPILE_UNIT, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDSubprogram(const MDSubprogram *N,
+                               const ValueEnumerator &VE,
+                               BitstreamWriter &Stream,
+                               SmallVectorImpl<uint64_t> &Record,
+                               unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawLinkageName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(N->getLine());
+  Record.push_back(VE.getMetadataOrNullID(N->getType()));
+  Record.push_back(N->isLocalToUnit());
+  Record.push_back(N->isDefinition());
+  Record.push_back(N->getScopeLine());
+  Record.push_back(VE.getMetadataOrNullID(N->getContainingType()));
+  Record.push_back(N->getVirtuality());
+  Record.push_back(N->getVirtualIndex());
+  Record.push_back(N->getFlags());
+  Record.push_back(N->isOptimized());
+  Record.push_back(VE.getMetadataOrNullID(N->getFunction()));
+  Record.push_back(VE.getMetadataOrNullID(N->getTemplateParams()));
+  Record.push_back(VE.getMetadataOrNullID(N->getDeclaration()));
+  Record.push_back(VE.getMetadataOrNullID(N->getVariables()));
+
+  Stream.EmitRecord(bitc::METADATA_SUBPROGRAM, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDLexicalBlock(const MDLexicalBlock *N,
+                               const ValueEnumerator &VE,
+                               BitstreamWriter &Stream,
+                               SmallVectorImpl<uint64_t> &Record,
+                               unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(N->getLine());
+  Record.push_back(N->getColumn());
+
+  Stream.EmitRecord(bitc::METADATA_LEXICAL_BLOCK, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDLexicalBlockFile(const MDLexicalBlockFile *N,
+                                    const ValueEnumerator &VE,
+                                    BitstreamWriter &Stream,
+                                    SmallVectorImpl<uint64_t> &Record,
+                                    unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(N->getDiscriminator());
+
+  Stream.EmitRecord(bitc::METADATA_LEXICAL_BLOCK_FILE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDNamespace(const MDNamespace *N, const ValueEnumerator &VE,
+                             BitstreamWriter &Stream,
+                             SmallVectorImpl<uint64_t> &Record,
+                             unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(N->getLine());
+
+  Stream.EmitRecord(bitc::METADATA_NAMESPACE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDTemplateTypeParameter(const MDTemplateTypeParameter *N,
+                                         const ValueEnumerator &VE,
+                                         BitstreamWriter &Stream,
+                                         SmallVectorImpl<uint64_t> &Record,
+                                         unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getType()));
+
+  Stream.EmitRecord(bitc::METADATA_TEMPLATE_TYPE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDTemplateValueParameter(const MDTemplateValueParameter *N,
+                                          const ValueEnumerator &VE,
+                                          BitstreamWriter &Stream,
+                                          SmallVectorImpl<uint64_t> &Record,
+                                          unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getTag());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getType()));
+  Record.push_back(VE.getMetadataOrNullID(N->getValue()));
+
+  Stream.EmitRecord(bitc::METADATA_TEMPLATE_VALUE, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDGlobalVariable(const MDGlobalVariable *N,
+                                  const ValueEnumerator &VE,
+                                  BitstreamWriter &Stream,
+                                  SmallVectorImpl<uint64_t> &Record,
+                                  unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawLinkageName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(N->getLine());
+  Record.push_back(VE.getMetadataOrNullID(N->getType()));
+  Record.push_back(N->isLocalToUnit());
+  Record.push_back(N->isDefinition());
+  Record.push_back(VE.getMetadataOrNullID(N->getVariable()));
+  Record.push_back(VE.getMetadataOrNullID(N->getStaticDataMemberDeclaration()));
+
+  Stream.EmitRecord(bitc::METADATA_GLOBAL_VAR, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDLocalVariable(const MDLocalVariable *N,
+                                 const ValueEnumerator &VE,
+                                 BitstreamWriter &Stream,
+                                 SmallVectorImpl<uint64_t> &Record,
+                                 unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getTag());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(N->getLine());
+  Record.push_back(VE.getMetadataOrNullID(N->getType()));
+  Record.push_back(N->getArg());
+  Record.push_back(N->getFlags());
+  Record.push_back(VE.getMetadataOrNullID(N->getInlinedAt()));
+
+  Stream.EmitRecord(bitc::METADATA_LOCAL_VAR, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDExpression(const MDExpression *N, const ValueEnumerator &,
+                              BitstreamWriter &Stream,
+                              SmallVectorImpl<uint64_t> &Record,
+                              unsigned Abbrev) {
+  Record.reserve(N->getElements().size() + 1);
+
+  Record.push_back(N->isDistinct());
+  Record.append(N->elements_begin(), N->elements_end());
+
+  Stream.EmitRecord(bitc::METADATA_EXPRESSION, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDObjCProperty(const MDObjCProperty *N,
+                                 const ValueEnumerator &VE,
+                                 BitstreamWriter &Stream,
+                                 SmallVectorImpl<uint64_t> &Record,
+                                 unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getFile()));
+  Record.push_back(N->getLine());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawSetterName()));
+  Record.push_back(VE.getMetadataOrNullID(N->getRawGetterName()));
+  Record.push_back(N->getAttributes());
+  Record.push_back(VE.getMetadataOrNullID(N->getType()));
+
+  Stream.EmitRecord(bitc::METADATA_OBJC_PROPERTY, Record, Abbrev);
+  Record.clear();
+}
+
+static void WriteMDImportedEntity(const MDImportedEntity *N,
+                                  const ValueEnumerator &VE,
+                                  BitstreamWriter &Stream,
+                                  SmallVectorImpl<uint64_t> &Record,
+                                  unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getTag());
+  Record.push_back(VE.getMetadataOrNullID(N->getScope()));
+  Record.push_back(VE.getMetadataOrNullID(N->getEntity()));
+  Record.push_back(N->getLine());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+
+  Stream.EmitRecord(bitc::METADATA_IMPORTED_ENTITY, Record, Abbrev);
   Record.clear();
 }
 
 static void WriteModuleMetadata(const Module *M,
                                 const ValueEnumerator &VE,
                                 BitstreamWriter &Stream) {
-  const auto &Vals = VE.getMDValues();
-  bool StartedMetadataBlock = false;
+  const auto &MDs = VE.getMDs();
+  if (MDs.empty() && M->named_metadata_empty())
+    return;
+
+  Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
+
   unsigned MDSAbbrev = 0;
-  SmallVector<uint64_t, 64> Record;
-  for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
+  if (VE.hasMDString()) {
+    // Abbrev for METADATA_STRING.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
+    MDSAbbrev = Stream.EmitAbbrev(Abbv);
+  }
 
-    if (const MDNode *N = dyn_cast<MDNode>(Vals[i])) {
-      if (!N->isFunctionLocal() || !N->getFunction()) {
-        if (!StartedMetadataBlock) {
-          Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
-          StartedMetadataBlock = true;
-        }
-        WriteMDNode(N, VE, Stream, Record);
-      }
-    } else if (const MDString *MDS = dyn_cast<MDString>(Vals[i])) {
-      if (!StartedMetadataBlock)  {
-        Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
-
-        // Abbrev for METADATA_STRING.
-        BitCodeAbbrev *Abbv = new BitCodeAbbrev();
-        Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING));
-        Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
-        Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
-        MDSAbbrev = Stream.EmitAbbrev(Abbv);
-        StartedMetadataBlock = true;
-      }
+  // Initialize MDNode abbreviations.
+#define HANDLE_MDNODE_LEAF(CLASS) unsigned CLASS##Abbrev = 0;
+#include "llvm/IR/Metadata.def"
 
-      // Code: [strchar x N]
-      Record.append(MDS->begin(), MDS->end());
+  if (VE.hasMDLocation()) {
+    // Abbrev for METADATA_LOCATION.
+    //
+    // Assume the column is usually under 128, and always output the inlined-at
+    // location (it's never more expensive than building an array size 1).
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_LOCATION));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
+    MDLocationAbbrev = Stream.EmitAbbrev(Abbv);
+  }
 
-      // Emit the finished record.
-      Stream.EmitRecord(bitc::METADATA_STRING, Record, MDSAbbrev);
-      Record.clear();
-    }
+  if (VE.hasGenericDebugNode()) {
+    // Abbrev for METADATA_GENERIC_DEBUG.
+    //
+    // Assume the column is usually under 128, and always output the inlined-at
+    // location (it's never more expensive than building an array size 1).
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_GENERIC_DEBUG));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
+    GenericDebugNodeAbbrev = Stream.EmitAbbrev(Abbv);
   }
 
-  // Write named metadata.
-  for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
-       E = M->named_metadata_end(); I != E; ++I) {
-    const NamedMDNode *NMD = I;
-    if (!StartedMetadataBlock)  {
-      Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
-      StartedMetadataBlock = true;
+  unsigned NameAbbrev = 0;
+  if (!M->named_metadata_empty()) {
+    // Abbrev for METADATA_NAME.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_NAME));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
+    NameAbbrev = Stream.EmitAbbrev(Abbv);
+  }
+
+  SmallVector<uint64_t, 64> Record;
+  for (const Metadata *MD : MDs) {
+    if (const MDNode *N = dyn_cast<MDNode>(MD)) {
+      switch (N->getMetadataID()) {
+      default:
+        llvm_unreachable("Invalid MDNode subclass");
+#define HANDLE_MDNODE_LEAF(CLASS)                                              \
+  case Metadata::CLASS##Kind:                                                  \
+    Write##CLASS(cast<CLASS>(N), VE, Stream, Record, CLASS##Abbrev);           \
+    continue;
+#include "llvm/IR/Metadata.def"
+      }
     }
+    if (const auto *MDC = dyn_cast<ConstantAsMetadata>(MD)) {
+      WriteValueAsMetadata(MDC, VE, Stream, Record);
+      continue;
+    }
+    const MDString *MDS = cast<MDString>(MD);
+    // Code: [strchar x N]
+    Record.append(MDS->bytes_begin(), MDS->bytes_end());
 
+    // Emit the finished record.
+    Stream.EmitRecord(bitc::METADATA_STRING, Record, MDSAbbrev);
+    Record.clear();
+  }
+
+  // Write named metadata.
+  for (const NamedMDNode &NMD : M->named_metadata()) {
     // Write name.
-    StringRef Str = NMD->getName();
-    for (unsigned i = 0, e = Str.size(); i != e; ++i)
-      Record.push_back(Str[i]);
-    Stream.EmitRecord(bitc::METADATA_NAME, Record, 0/*TODO*/);
+    StringRef Str = NMD.getName();
+    Record.append(Str.bytes_begin(), Str.bytes_end());
+    Stream.EmitRecord(bitc::METADATA_NAME, Record, NameAbbrev);
     Record.clear();
 
     // Write named metadata operands.
-    for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i)
-      Record.push_back(VE.getValueID(NMD->getOperand(i)));
+    for (const MDNode *N : NMD.operands())
+      Record.push_back(VE.getMetadataID(N));
     Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
     Record.clear();
   }
 
-  if (StartedMetadataBlock)
-    Stream.ExitBlock();
+  Stream.ExitBlock();
 }
 
 static void WriteFunctionLocalMetadata(const Function &F,
@@ -824,16 +1251,16 @@ static void WriteFunctionLocalMetadata(const Function &F,
                                        BitstreamWriter &Stream) {
   bool StartedMetadataBlock = false;
   SmallVector<uint64_t, 64> Record;
-  const SmallVectorImpl<const MDNode *> &Vals = VE.getFunctionLocalMDValues();
-  for (unsigned i = 0, e = Vals.size(); i != e; ++i)
-    if (const MDNode *N = Vals[i])
-      if (N->isFunctionLocal() && N->getFunction() == &F) {
-        if (!StartedMetadataBlock) {
-          Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
-          StartedMetadataBlock = true;
-        }
-        WriteMDNode(N, VE, Stream, Record);
-      }
+  const SmallVectorImpl<const LocalAsMetadata *> &MDs =
+      VE.getFunctionLocalMDs();
+  for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
+    assert(MDs[i] && "Expected valid function-local metadata");
+    if (!StartedMetadataBlock) {
+      Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
+      StartedMetadataBlock = true;
+    }
+    WriteValueAsMetadata(MDs[i], VE, Stream, Record);
+  }
 
   if (StartedMetadataBlock)
     Stream.ExitBlock();
@@ -863,7 +1290,7 @@ static void WriteMetadataAttachment(const Function &F,
 
       for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
         Record.push_back(MDs[i].first);
-        Record.push_back(VE.getValueID(MDs[i].second));
+        Record.push_back(VE.getMetadataID(MDs[i].second));
       }
       Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
       Record.clear();
@@ -966,14 +1393,12 @@ static void WriteConstants(unsigned FirstVal, unsigned LastVal,
       // Add the asm string.
       const std::string &AsmStr = IA->getAsmString();
       Record.push_back(AsmStr.size());
-      for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
-        Record.push_back(AsmStr[i]);
+      Record.append(AsmStr.begin(), AsmStr.end());
 
       // Add the constraint string.
       const std::string &ConstraintStr = IA->getConstraintString();
       Record.push_back(ConstraintStr.size());
-      for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
-        Record.push_back(ConstraintStr[i]);
+      Record.append(ConstraintStr.begin(), ConstraintStr.end());
       Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
       Record.clear();
       continue;
@@ -1251,19 +1676,21 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
     }
     break;
 
-  case Instruction::GetElementPtr:
+  case Instruction::GetElementPtr: {
     Code = bitc::FUNC_CODE_INST_GEP;
-    if (cast<GEPOperator>(&I)->isInBounds())
-      Code = bitc::FUNC_CODE_INST_INBOUNDS_GEP;
+    AbbrevToUse = FUNCTION_INST_GEP_ABBREV;
+    auto &GEPInst = cast<GetElementPtrInst>(I);
+    Vals.push_back(GEPInst.isInBounds());
+    Vals.push_back(VE.getTypeID(GEPInst.getSourceElementType()));
     for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
       PushValueAndType(I.getOperand(i), InstID, Vals, VE);
     break;
+  }
   case Instruction::ExtractValue: {
     Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
     const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
-    for (const unsigned *i = EVI->idx_begin(), *e = EVI->idx_end(); i != e; ++i)
-      Vals.push_back(*i);
+    Vals.append(EVI->idx_begin(), EVI->idx_end());
     break;
   }
   case Instruction::InsertValue: {
@@ -1271,8 +1698,7 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
     PushValueAndType(I.getOperand(1), InstID, Vals, VE);
     const InsertValueInst *IVI = cast<InsertValueInst>(&I);
-    for (const unsigned *i = IVI->idx_begin(), *e = IVI->idx_end(); i != e; ++i)
-      Vals.push_back(*i);
+    Vals.append(IVI->idx_begin(), IVI->idx_end());
     break;
   }
   case Instruction::Select:
@@ -1449,6 +1875,7 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
       if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))  // ptr
         AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
     }
+    Vals.push_back(VE.getTypeID(I.getType()));
     Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
     Vals.push_back(cast<LoadInst>(I).isVolatile());
     if (cast<LoadInst>(I).isAtomic()) {
@@ -1608,9 +2035,7 @@ static void WriteUseList(ValueEnumerator &VE, UseListOrder &&Order,
   else
     Code = bitc::USELIST_CODE_DEFAULT;
 
-  SmallVector<uint64_t, 64> Record;
-  for (unsigned I : Order.Shuffle)
-    Record.push_back(I);
+  SmallVector<uint64_t, 64> Record(Order.Shuffle.begin(), Order.Shuffle.end());
   Record.push_back(VE.getValueID(Order.V));
   Stream.EmitRecord(Code, Record);
 }
@@ -1683,11 +2108,12 @@ static void WriteFunction(const Function &F, ValueEnumerator &VE,
       } else {
         MDNode *Scope, *IA;
         DL.getScopeAndInlinedAt(Scope, IA, I->getContext());
+        assert(Scope && "Expected valid scope");
 
         Vals.push_back(DL.getLine());
         Vals.push_back(DL.getCol());
-        Vals.push_back(Scope ? VE.getValueID(Scope)+1 : 0);
-        Vals.push_back(IA ? VE.getValueID(IA)+1 : 0);
+        Vals.push_back(VE.getMetadataOrNullID(Scope));
+        Vals.push_back(VE.getMetadataOrNullID(IA));
         Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC, Vals);
         Vals.clear();
 
@@ -1761,7 +2187,7 @@ static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
-                              Log2_32_Ceil(VE.getTypes().size()+1)));
+                              VE.computeBitsRequiredForTypeIndicies()));
     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
                                    Abbv) != CONSTANTS_SETTYPE_ABBREV)
       llvm_unreachable("Unexpected abbrev ordering!");
@@ -1781,7 +2207,7 @@ static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
-                              Log2_32_Ceil(VE.getTypes().size()+1)));
+                              VE.computeBitsRequiredForTypeIndicies()));
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
 
     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
@@ -1802,6 +2228,8 @@ static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,    // dest ty
+                              VE.computeBitsRequiredForTypeIndicies()));
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
@@ -1834,7 +2262,7 @@ static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));    // OpVal
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // dest ty
-                              Log2_32_Ceil(VE.getTypes().size()+1)));
+                              VE.computeBitsRequiredForTypeIndicies()));
     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // opc
     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
                                    Abbv) != FUNCTION_INST_CAST_ABBREV)
@@ -1863,6 +2291,18 @@ static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
                                    Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
       llvm_unreachable("Unexpected abbrev ordering!");
   }
+  {
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_GEP));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, // dest ty
+                              Log2_32_Ceil(VE.getTypes().size() + 1)));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
+    if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, Abbv) !=
+        FUNCTION_INST_GEP_ABBREV)
+      llvm_unreachable("Unexpected abbrev ordering!");
+  }
 
   Stream.ExitBlock();
 }
diff --git a/lib/Bitcode/Writer/BitcodeWriterPass.cpp b/lib/Bitcode/Writer/BitcodeWriterPass.cpp
index 4167f6d..25456a4 100644
--- a/lib/Bitcode/Writer/BitcodeWriterPass.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriterPass.cpp
@@ -18,8 +18,8 @@
 #include "llvm/Pass.h"
 using namespace llvm;
 
-PreservedAnalyses BitcodeWriterPass::run(Module *M) {
-  WriteBitcodeToFile(M, OS);
+PreservedAnalyses BitcodeWriterPass::run(Module &M) {
+  WriteBitcodeToFile(&M, OS);
   return PreservedAnalyses::all();
 }
 
diff --git a/lib/Bitcode/Writer/ValueEnumerator.cpp b/lib/Bitcode/Writer/ValueEnumerator.cpp
index f065c83..549e94f 100644
--- a/lib/Bitcode/Writer/ValueEnumerator.cpp
+++ b/lib/Bitcode/Writer/ValueEnumerator.cpp
@@ -15,6 +15,7 @@
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/IR/Constants.h"
+#include "llvm/IR/DebugInfoMetadata.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/Module.h"
@@ -85,10 +86,14 @@ static OrderMap orderModule(const Module &M) {
   for (const GlobalAlias &A : M.aliases())
     if (!isa<GlobalValue>(A.getAliasee()))
       orderValue(A.getAliasee(), OM);
-  for (const Function &F : M)
+  for (const Function &F : M) {
     if (F.hasPrefixData())
       if (!isa<GlobalValue>(F.getPrefixData()))
         orderValue(F.getPrefixData(), OM);
+    if (F.hasPrologueData())
+      if (!isa<GlobalValue>(F.getPrologueData()))
+        orderValue(F.getPrologueData(), OM);
+  }
   OM.LastGlobalConstantID = OM.size();
 
   // Initializers of GlobalValues are processed in
@@ -264,9 +269,12 @@ static UseListOrderStack predictUseListOrder(const Module &M) {
       predictValueUseListOrder(G.getInitializer(), nullptr, OM, Stack);
   for (const GlobalAlias &A : M.aliases())
     predictValueUseListOrder(A.getAliasee(), nullptr, OM, Stack);
-  for (const Function &F : M)
+  for (const Function &F : M) {
     if (F.hasPrefixData())
       predictValueUseListOrder(F.getPrefixData(), nullptr, OM, Stack);
+    if (F.hasPrologueData())
+      predictValueUseListOrder(F.getPrologueData(), nullptr, OM, Stack);
+  }
 
   return Stack;
 }
@@ -275,7 +283,8 @@ static bool isIntOrIntVectorValue(const std::pair<const Value*, unsigned> &V) {
   return V.first->getType()->isIntOrIntVectorTy();
 }
 
-ValueEnumerator::ValueEnumerator(const Module &M) {
+ValueEnumerator::ValueEnumerator(const Module &M)
+    : HasMDString(false), HasMDLocation(false), HasGenericDebugNode(false) {
   if (shouldPreserveBitcodeUseListOrder())
     UseListOrders = predictUseListOrder(M);
 
@@ -314,6 +323,17 @@ ValueEnumerator::ValueEnumerator(const Module &M) {
     if (I->hasPrefixData())
       EnumerateValue(I->getPrefixData());
 
+  // Enumerate the prologue data constants.
+  for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I)
+    if (I->hasPrologueData())
+      EnumerateValue(I->getPrologueData());
+
+  // Enumerate the metadata type.
+  //
+  // TODO: Move this to ValueEnumerator::EnumerateOperandType() once bitcode
+  // only encodes the metadata type when it's used as a value.
+  EnumerateType(Type::getMetadataTy(M.getContext()));
+
   // Insert constants and metadata that are named at module level into the slot
   // pool so that the module symbol table can refer to them...
   EnumerateValueSymbolTable(M.getValueSymbolTable());
@@ -329,11 +349,17 @@ ValueEnumerator::ValueEnumerator(const Module &M) {
     for (const BasicBlock &BB : F)
       for (const Instruction &I : BB) {
         for (const Use &Op : I.operands()) {
-          if (MDNode *MD = dyn_cast<MDNode>(&Op))
-            if (MD->isFunctionLocal() && MD->getFunction())
-              // These will get enumerated during function-incorporation.
-              continue;
-          EnumerateOperandType(Op);
+          auto *MD = dyn_cast<MetadataAsValue>(&Op);
+          if (!MD) {
+            EnumerateOperandType(Op);
+            continue;
+          }
+
+          // Local metadata is enumerated during function-incorporation.
+          if (isa<LocalAsMetadata>(MD->getMetadata()))
+            continue;
+
+          EnumerateMetadata(MD->getMetadata());
         }
         EnumerateType(I.getType());
         if (const CallInst *CI = dyn_cast<CallInst>(&I))
@@ -377,11 +403,8 @@ void ValueEnumerator::setInstructionID(const Instruction *I) {
 }
 
 unsigned ValueEnumerator::getValueID(const Value *V) const {
-  if (isa<MDNode>(V) || isa<MDString>(V)) {
-    ValueMapType::const_iterator I = MDValueMap.find(V);
-    assert(I != MDValueMap.end() && "Value not in slotcalculator!");
-    return I->second-1;
-  }
+  if (auto *MD = dyn_cast<MetadataAsValue>(V))
+    return getMetadataID(MD->getMetadata());
 
   ValueMapType::const_iterator I = ValueMap.find(V);
   assert(I != ValueMap.end() && "Value not in slotcalculator!");
@@ -424,6 +447,18 @@ void ValueEnumerator::print(raw_ostream &OS, const ValueMapType &Map,
   }
 }
 
+void ValueEnumerator::print(raw_ostream &OS, const MetadataMapType &Map,
+                            const char *Name) const {
+
+  OS << "Map Name: " << Name << "\n";
+  OS << "Size: " << Map.size() << "\n";
+  for (auto I = Map.begin(), E = Map.end(); I != E; ++I) {
+    const Metadata *MD = I->first;
+    OS << "Metadata: slot = " << I->second << "\n";
+    MD->print(OS);
+  }
+}
+
 /// OptimizeConstants - Reorder constant pool for denser encoding.
 void ValueEnumerator::OptimizeConstants(unsigned CstStart, unsigned CstEnd) {
   if (CstStart == CstEnd || CstStart+1 == CstEnd) return;
@@ -481,25 +516,18 @@ void ValueEnumerator::EnumerateNamedMDNode(const NamedMDNode *MD) {
 /// and types referenced by the given MDNode.
 void ValueEnumerator::EnumerateMDNodeOperands(const MDNode *N) {
   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
-    if (Value *V = N->getOperand(i)) {
-      if (isa<MDNode>(V) || isa<MDString>(V))
-        EnumerateMetadata(V);
-      else if (!isa<Instruction>(V) && !isa<Argument>(V))
-        EnumerateValue(V);
-    } else
-      EnumerateType(Type::getVoidTy(N->getContext()));
+    Metadata *MD = N->getOperand(i);
+    if (!MD)
+      continue;
+    assert(!isa<LocalAsMetadata>(MD) && "MDNodes cannot be function-local");
+    EnumerateMetadata(MD);
   }
 }
 
-void ValueEnumerator::EnumerateMetadata(const Value *MD) {
-  assert((isa<MDNode>(MD) || isa<MDString>(MD)) && "Invalid metadata kind");
-
-  // Skip function-local nodes themselves, but walk their operands.
-  const MDNode *N = dyn_cast<MDNode>(MD);
-  if (N && N->isFunctionLocal() && N->getFunction()) {
-    EnumerateMDNodeOperands(N);
-    return;
-  }
+void ValueEnumerator::EnumerateMetadata(const Metadata *MD) {
+  assert(
+      (isa<MDNode>(MD) || isa<MDString>(MD) || isa<ConstantAsMetadata>(MD)) &&
+      "Invalid metadata kind");
 
   // Insert a dummy ID to block the co-recursive call to
   // EnumerateMDNodeOperands() from re-visiting MD in a cyclic graph.
@@ -508,55 +536,43 @@ void ValueEnumerator::EnumerateMetadata(const Value *MD) {
   if (!MDValueMap.insert(std::make_pair(MD, 0)).second)
     return;
 
-  // Enumerate the type of this value.
-  EnumerateType(MD->getType());
-
   // Visit operands first to minimize RAUW.
-  if (N)
+  if (auto *N = dyn_cast<MDNode>(MD))
     EnumerateMDNodeOperands(N);
+  else if (auto *C = dyn_cast<ConstantAsMetadata>(MD))
+    EnumerateValue(C->getValue());
+
+  HasMDString |= isa<MDString>(MD);
+  HasMDLocation |= isa<MDLocation>(MD);
+  HasGenericDebugNode |= isa<GenericDebugNode>(MD);
 
   // Replace the dummy ID inserted above with the correct one.  MDValueMap may
   // have changed by inserting operands, so we need a fresh lookup here.
-  MDValues.push_back(MD);
-  MDValueMap[MD] = MDValues.size();
+  MDs.push_back(MD);
+  MDValueMap[MD] = MDs.size();
 }
 
 /// EnumerateFunctionLocalMetadataa - Incorporate function-local metadata
-/// information reachable from the given MDNode.
-void ValueEnumerator::EnumerateFunctionLocalMetadata(const MDNode *N) {
-  assert(N->isFunctionLocal() && N->getFunction() &&
-         "EnumerateFunctionLocalMetadata called on non-function-local mdnode!");
-
-  // Enumerate the type of this value.
-  EnumerateType(N->getType());
-
+/// information reachable from the metadata.
+void ValueEnumerator::EnumerateFunctionLocalMetadata(
+    const LocalAsMetadata *Local) {
   // Check to see if it's already in!
-  unsigned &MDValueID = MDValueMap[N];
+  unsigned &MDValueID = MDValueMap[Local];
   if (MDValueID)
     return;
 
-  MDValues.push_back(N);
-  MDValueID = MDValues.size();
-
-  // To incoroporate function-local information visit all function-local
-  // MDNodes and all function-local values they reference.
-  for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
-    if (Value *V = N->getOperand(i)) {
-      if (MDNode *O = dyn_cast<MDNode>(V)) {
-        if (O->isFunctionLocal() && O->getFunction())
-          EnumerateFunctionLocalMetadata(O);
-      } else if (isa<Instruction>(V) || isa<Argument>(V))
-        EnumerateValue(V);
-    }
+  MDs.push_back(Local);
+  MDValueID = MDs.size();
+
+  EnumerateValue(Local->getValue());
 
-  // Also, collect all function-local MDNodes for easy access.
-  FunctionLocalMDs.push_back(N);
+  // Also, collect all function-local metadata for easy access.
+  FunctionLocalMDs.push_back(Local);
 }
 
 void ValueEnumerator::EnumerateValue(const Value *V) {
   assert(!V->getType()->isVoidTy() && "Can't insert void values!");
-  assert(!isa<MDNode>(V) && !isa<MDString>(V) &&
-         "EnumerateValue doesn't handle Metadata!");
+  assert(!isa<MetadataAsValue>(V) && "EnumerateValue doesn't handle Metadata!");
 
   // Check to see if it's already in!
   unsigned &ValueID = ValueMap[V];
@@ -620,9 +636,8 @@ void ValueEnumerator::EnumerateType(Type *Ty) {
 
   // Enumerate all of the subtypes before we enumerate this type.  This ensures
   // that the type will be enumerated in an order that can be directly built.
-  for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end();
-       I != E; ++I)
-    EnumerateType(*I);
+  for (Type *SubTy : Ty->subtypes())
+    EnumerateType(SubTy);
 
   // Refresh the TypeID pointer in case the table rehashed.
   TypeID = &TypeMap[Ty];
@@ -646,30 +661,35 @@ void ValueEnumerator::EnumerateType(Type *Ty) {
 void ValueEnumerator::EnumerateOperandType(const Value *V) {
   EnumerateType(V->getType());
 
-  if (const Constant *C = dyn_cast<Constant>(V)) {
-    // If this constant is already enumerated, ignore it, we know its type must
-    // be enumerated.
-    if (ValueMap.count(V)) return;
+  if (auto *MD = dyn_cast<MetadataAsValue>(V)) {
+    assert(!isa<LocalAsMetadata>(MD->getMetadata()) &&
+           "Function-local metadata should be left for later");
+
+    EnumerateMetadata(MD->getMetadata());
+    return;
+  }
 
-    // This constant may have operands, make sure to enumerate the types in
-    // them.
-    for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i) {
-      const Value *Op = C->getOperand(i);
+  const Constant *C = dyn_cast<Constant>(V);
+  if (!C)
+    return;
 
-      // Don't enumerate basic blocks here, this happens as operands to
-      // blockaddress.
-      if (isa<BasicBlock>(Op)) continue;
+  // If this constant is already enumerated, ignore it, we know its type must
+  // be enumerated.
+  if (ValueMap.count(C))
+    return;
 
-      EnumerateOperandType(Op);
-    }
+  // This constant may have operands, make sure to enumerate the types in
+  // them.
+  for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i) {
+    const Value *Op = C->getOperand(i);
 
-    if (const MDNode *N = dyn_cast<MDNode>(V)) {
-      for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
-        if (Value *Elem = N->getOperand(i))
-          EnumerateOperandType(Elem);
-    }
-  } else if (isa<MDString>(V) || isa<MDNode>(V))
-    EnumerateMetadata(V);
+    // Don't enumerate basic blocks here, this happens as operands to
+    // blockaddress.
+    if (isa<BasicBlock>(Op))
+      continue;
+
+    EnumerateOperandType(Op);
+  }
 }
 
 void ValueEnumerator::EnumerateAttributes(AttributeSet PAL) {
@@ -697,7 +717,7 @@ void ValueEnumerator::EnumerateAttributes(AttributeSet PAL) {
 void ValueEnumerator::incorporateFunction(const Function &F) {
   InstructionCount = 0;
   NumModuleValues = Values.size();
-  NumModuleMDValues = MDValues.size();
+  NumModuleMDs = MDs.size();
 
   // Adding function arguments to the value table.
   for (Function::const_arg_iterator I = F.arg_begin(), E = F.arg_end();
@@ -728,24 +748,16 @@ void ValueEnumerator::incorporateFunction(const Function &F) {
 
   FirstInstID = Values.size();
 
-  SmallVector<MDNode *, 8> FnLocalMDVector;
+  SmallVector<LocalAsMetadata *, 8> FnLocalMDVector;
   // Add all of the instructions.
   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();
            OI != E; ++OI) {
-        if (MDNode *MD = dyn_cast<MDNode>(*OI))
-          if (MD->isFunctionLocal() && MD->getFunction())
+        if (auto *MD = dyn_cast<MetadataAsValue>(&*OI))
+          if (auto *Local = dyn_cast<LocalAsMetadata>(MD->getMetadata()))
             // Enumerate metadata after the instructions they might refer to.
-            FnLocalMDVector.push_back(MD);
-      }
-
-      SmallVector<std::pair<unsigned, MDNode *>, 8> MDs;
-      I->getAllMetadataOtherThanDebugLoc(MDs);
-      for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
-        MDNode *N = MDs[i].second;
-        if (N->isFunctionLocal() && N->getFunction())
-          FnLocalMDVector.push_back(N);
+            FnLocalMDVector.push_back(Local);
       }
 
       if (!I->getType()->isVoidTy())
@@ -762,13 +774,13 @@ void ValueEnumerator::purgeFunction() {
   /// Remove purged values from the ValueMap.
   for (unsigned i = NumModuleValues, e = Values.size(); i != e; ++i)
     ValueMap.erase(Values[i].first);
-  for (unsigned i = NumModuleMDValues, e = MDValues.size(); i != e; ++i)
-    MDValueMap.erase(MDValues[i]);
+  for (unsigned i = NumModuleMDs, e = MDs.size(); i != e; ++i)
+    MDValueMap.erase(MDs[i]);
   for (unsigned i = 0, e = BasicBlocks.size(); i != e; ++i)
     ValueMap.erase(BasicBlocks[i]);
 
   Values.resize(NumModuleValues);
-  MDValues.resize(NumModuleMDValues);
+  MDs.resize(NumModuleMDs);
   BasicBlocks.clear();
   FunctionLocalMDs.clear();
 }
@@ -792,3 +804,6 @@ unsigned ValueEnumerator::getGlobalBasicBlockID(const BasicBlock *BB) const {
   return getGlobalBasicBlockID(BB);
 }
 
+uint64_t ValueEnumerator::computeBitsRequiredForTypeIndicies() const {
+  return Log2_32_Ceil(getTypes().size() + 1);
+}
diff --git a/lib/Bitcode/Writer/ValueEnumerator.h b/lib/Bitcode/Writer/ValueEnumerator.h
index 563c214..b94c370 100644
--- a/lib/Bitcode/Writer/ValueEnumerator.h
+++ b/lib/Bitcode/Writer/ValueEnumerator.h
@@ -30,6 +30,8 @@ class BasicBlock;
 class Comdat;
 class Function;
 class Module;
+class Metadata;
+class LocalAsMetadata;
 class MDNode;
 class NamedMDNode;
 class AttributeSet;
@@ -58,9 +60,13 @@ private:
   typedef UniqueVector<const Comdat *> ComdatSetType;
   ComdatSetType Comdats;
 
-  std::vector<const Value *> MDValues;
-  SmallVector<const MDNode *, 8> FunctionLocalMDs;
-  ValueMapType MDValueMap;
+  std::vector<const Metadata *> MDs;
+  SmallVector<const LocalAsMetadata *, 8> FunctionLocalMDs;
+  typedef DenseMap<const Metadata *, unsigned> MetadataMapType;
+  MetadataMapType MDValueMap;
+  bool HasMDString;
+  bool HasMDLocation;
+  bool HasGenericDebugNode;
 
   typedef DenseMap<AttributeSet, unsigned> AttributeGroupMapType;
   AttributeGroupMapType AttributeGroupMap;
@@ -88,20 +94,34 @@ private:
 
   /// When a function is incorporated, this is the size of the MDValues list
   /// before incorporation.
-  unsigned NumModuleMDValues;
+  unsigned NumModuleMDs;
 
   unsigned FirstFuncConstantID;
   unsigned FirstInstID;
 
-  ValueEnumerator(const ValueEnumerator &) LLVM_DELETED_FUNCTION;
-  void operator=(const ValueEnumerator &) LLVM_DELETED_FUNCTION;
+  ValueEnumerator(const ValueEnumerator &) = delete;
+  void operator=(const ValueEnumerator &) = delete;
 public:
   ValueEnumerator(const Module &M);
 
   void dump() const;
   void print(raw_ostream &OS, const ValueMapType &Map, const char *Name) const;
+  void print(raw_ostream &OS, const MetadataMapType &Map,
+             const char *Name) const;
 
   unsigned getValueID(const Value *V) const;
+  unsigned getMetadataID(const Metadata *MD) const {
+    auto ID = getMetadataOrNullID(MD);
+    assert(ID != 0 && "Metadata not in slotcalculator!");
+    return ID - 1;
+  }
+  unsigned getMetadataOrNullID(const Metadata *MD) const {
+    return MDValueMap.lookup(MD);
+  }
+
+  bool hasMDString() const { return HasMDString; }
+  bool hasMDLocation() const { return HasMDLocation; }
+  bool hasGenericDebugNode() const { return HasGenericDebugNode; }
 
   unsigned getTypeID(Type *T) const {
     TypeMapType::const_iterator I = TypeMap.find(T);
@@ -134,8 +154,8 @@ public:
   }
 
   const ValueList &getValues() const { return Values; }
-  const std::vector<const Value *> &getMDValues() const { return MDValues; }
-  const SmallVectorImpl<const MDNode *> &getFunctionLocalMDValues() const {
+  const std::vector<const Metadata *> &getMDs() const { return MDs; }
+  const SmallVectorImpl<const LocalAsMetadata *> &getFunctionLocalMDs() const {
     return FunctionLocalMDs;
   }
   const TypeList &getTypes() const { return Types; }
@@ -162,13 +182,14 @@ public:
   ///
   void incorporateFunction(const Function &F);
   void purgeFunction();
+  uint64_t computeBitsRequiredForTypeIndicies() const;
 
 private:
   void OptimizeConstants(unsigned CstStart, unsigned CstEnd);
 
   void EnumerateMDNodeOperands(const MDNode *N);
-  void EnumerateMetadata(const Value *MD);
-  void EnumerateFunctionLocalMetadata(const MDNode *N);
+  void EnumerateMetadata(const Metadata *MD);
+  void EnumerateFunctionLocalMetadata(const LocalAsMetadata *Local);
   void EnumerateNamedMDNode(const NamedMDNode *NMD);
   void EnumerateValue(const Value *V);
   void EnumerateType(Type *T);