AsmWriter/Bitcode: MDEnumerator
[oota-llvm.git] / lib / Bitcode / Writer / BitcodeWriter.cpp
index cc6b8b39fbdccb971ff285bc9ee7e86116959273..dfbfc9c0bea0e14cd0b5abbc5e695e70f1964523 100644 (file)
 #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"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Operator.h"
+#include "llvm/IR/UseListOrder.h"
 #include "llvm/IR/ValueSymbolTable.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ErrorHandling.h"
 #include <map>
 using namespace llvm;
 
-static cl::opt<bool>
-EnablePreserveUseListOrdering("enable-bc-uselist-preserve",
-                              cl::desc("Turn on experimental support for "
-                                       "use-list order preservation."),
-                              cl::init(false), cl::Hidden);
-
 /// These are manifest constants used by the bitcode writer. They do not need to
 /// be kept in sync with the reader, but need to be consistent within this file.
 enum {
@@ -60,10 +56,7 @@ enum {
   FUNCTION_INST_CAST_ABBREV,
   FUNCTION_INST_RET_VOID_ABBREV,
   FUNCTION_INST_RET_VAL_ABBREV,
-  FUNCTION_INST_UNREACHABLE_ABBREV,
-
-  // SwitchInst Magic
-  SWITCH_INST_MAGIC = 0x4B5 // May 2012 => 1205 => Hex
+  FUNCTION_INST_UNREACHABLE_ABBREV
 };
 
 static unsigned GetEncodedCastOpcode(unsigned Opcode) {
@@ -81,6 +74,7 @@ static unsigned GetEncodedCastOpcode(unsigned Opcode) {
   case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
   case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
   case Instruction::BitCast : return bitc::CAST_BITCAST;
+  case Instruction::AddrSpaceCast: return bitc::CAST_ADDRSPACECAST;
   }
 }
 
@@ -161,7 +155,147 @@ static void WriteStringRecord(unsigned Code, StringRef Str,
   Stream.EmitRecord(Code, Vals, AbbrevToUse);
 }
 
-// Emit information about parameter attributes.
+static uint64_t getAttrKindEncoding(Attribute::AttrKind Kind) {
+  switch (Kind) {
+  case Attribute::Alignment:
+    return bitc::ATTR_KIND_ALIGNMENT;
+  case Attribute::AlwaysInline:
+    return bitc::ATTR_KIND_ALWAYS_INLINE;
+  case Attribute::Builtin:
+    return bitc::ATTR_KIND_BUILTIN;
+  case Attribute::ByVal:
+    return bitc::ATTR_KIND_BY_VAL;
+  case Attribute::InAlloca:
+    return bitc::ATTR_KIND_IN_ALLOCA;
+  case Attribute::Cold:
+    return bitc::ATTR_KIND_COLD;
+  case Attribute::InlineHint:
+    return bitc::ATTR_KIND_INLINE_HINT;
+  case Attribute::InReg:
+    return bitc::ATTR_KIND_IN_REG;
+  case Attribute::JumpTable:
+    return bitc::ATTR_KIND_JUMP_TABLE;
+  case Attribute::MinSize:
+    return bitc::ATTR_KIND_MIN_SIZE;
+  case Attribute::Naked:
+    return bitc::ATTR_KIND_NAKED;
+  case Attribute::Nest:
+    return bitc::ATTR_KIND_NEST;
+  case Attribute::NoAlias:
+    return bitc::ATTR_KIND_NO_ALIAS;
+  case Attribute::NoBuiltin:
+    return bitc::ATTR_KIND_NO_BUILTIN;
+  case Attribute::NoCapture:
+    return bitc::ATTR_KIND_NO_CAPTURE;
+  case Attribute::NoDuplicate:
+    return bitc::ATTR_KIND_NO_DUPLICATE;
+  case Attribute::NoImplicitFloat:
+    return bitc::ATTR_KIND_NO_IMPLICIT_FLOAT;
+  case Attribute::NoInline:
+    return bitc::ATTR_KIND_NO_INLINE;
+  case Attribute::NonLazyBind:
+    return bitc::ATTR_KIND_NON_LAZY_BIND;
+  case Attribute::NonNull:
+    return bitc::ATTR_KIND_NON_NULL;
+  case Attribute::Dereferenceable:
+    return bitc::ATTR_KIND_DEREFERENCEABLE;
+  case Attribute::NoRedZone:
+    return bitc::ATTR_KIND_NO_RED_ZONE;
+  case Attribute::NoReturn:
+    return bitc::ATTR_KIND_NO_RETURN;
+  case Attribute::NoUnwind:
+    return bitc::ATTR_KIND_NO_UNWIND;
+  case Attribute::OptimizeForSize:
+    return bitc::ATTR_KIND_OPTIMIZE_FOR_SIZE;
+  case Attribute::OptimizeNone:
+    return bitc::ATTR_KIND_OPTIMIZE_NONE;
+  case Attribute::ReadNone:
+    return bitc::ATTR_KIND_READ_NONE;
+  case Attribute::ReadOnly:
+    return bitc::ATTR_KIND_READ_ONLY;
+  case Attribute::Returned:
+    return bitc::ATTR_KIND_RETURNED;
+  case Attribute::ReturnsTwice:
+    return bitc::ATTR_KIND_RETURNS_TWICE;
+  case Attribute::SExt:
+    return bitc::ATTR_KIND_S_EXT;
+  case Attribute::StackAlignment:
+    return bitc::ATTR_KIND_STACK_ALIGNMENT;
+  case Attribute::StackProtect:
+    return bitc::ATTR_KIND_STACK_PROTECT;
+  case Attribute::StackProtectReq:
+    return bitc::ATTR_KIND_STACK_PROTECT_REQ;
+  case Attribute::StackProtectStrong:
+    return bitc::ATTR_KIND_STACK_PROTECT_STRONG;
+  case Attribute::StructRet:
+    return bitc::ATTR_KIND_STRUCT_RET;
+  case Attribute::SanitizeAddress:
+    return bitc::ATTR_KIND_SANITIZE_ADDRESS;
+  case Attribute::SanitizeThread:
+    return bitc::ATTR_KIND_SANITIZE_THREAD;
+  case Attribute::SanitizeMemory:
+    return bitc::ATTR_KIND_SANITIZE_MEMORY;
+  case Attribute::UWTable:
+    return bitc::ATTR_KIND_UW_TABLE;
+  case Attribute::ZExt:
+    return bitc::ATTR_KIND_Z_EXT;
+  case Attribute::EndAttrKinds:
+    llvm_unreachable("Can not encode end-attribute kinds marker.");
+  case Attribute::None:
+    llvm_unreachable("Can not encode none-attribute.");
+  }
+
+  llvm_unreachable("Trying to encode unknown attribute");
+}
+
+static void WriteAttributeGroupTable(const ValueEnumerator &VE,
+                                     BitstreamWriter &Stream) {
+  const std::vector<AttributeSet> &AttrGrps = VE.getAttributeGroups();
+  if (AttrGrps.empty()) return;
+
+  Stream.EnterSubblock(bitc::PARAMATTR_GROUP_BLOCK_ID, 3);
+
+  SmallVector<uint64_t, 64> Record;
+  for (unsigned i = 0, e = AttrGrps.size(); i != e; ++i) {
+    AttributeSet AS = AttrGrps[i];
+    for (unsigned i = 0, e = AS.getNumSlots(); i != e; ++i) {
+      AttributeSet A = AS.getSlotAttributes(i);
+
+      Record.push_back(VE.getAttributeGroupID(A));
+      Record.push_back(AS.getSlotIndex(i));
+
+      for (AttributeSet::iterator I = AS.begin(0), E = AS.end(0);
+           I != E; ++I) {
+        Attribute Attr = *I;
+        if (Attr.isEnumAttribute()) {
+          Record.push_back(0);
+          Record.push_back(getAttrKindEncoding(Attr.getKindAsEnum()));
+        } else if (Attr.isIntAttribute()) {
+          Record.push_back(1);
+          Record.push_back(getAttrKindEncoding(Attr.getKindAsEnum()));
+          Record.push_back(Attr.getValueAsInt());
+        } else {
+          StringRef Kind = Attr.getKindAsString();
+          StringRef Val = Attr.getValueAsString();
+
+          Record.push_back(Val.empty() ? 3 : 4);
+          Record.append(Kind.begin(), Kind.end());
+          Record.push_back(0);
+          if (!Val.empty()) {
+            Record.append(Val.begin(), Val.end());
+            Record.push_back(0);
+          }
+        }
+      }
+
+      Stream.EmitRecord(bitc::PARAMATTR_GRP_CODE_ENTRY, Record);
+      Record.clear();
+    }
+  }
+
+  Stream.ExitBlock();
+}
+
 static void WriteAttributeTable(const ValueEnumerator &VE,
                                 BitstreamWriter &Stream) {
   const std::vector<AttributeSet> &Attrs = VE.getAttributes();
@@ -172,11 +306,8 @@ static void WriteAttributeTable(const ValueEnumerator &VE,
   SmallVector<uint64_t, 64> Record;
   for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
     const AttributeSet &A = Attrs[i];
-    for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
-      const AttributeWithIndex &PAWI = A.getSlot(i);
-      Record.push_back(A.getSlotIndex(i));
-      Record.push_back(Attribute::encodeLLVMAttributesForBitcode(PAWI.Attrs));
-    }
+    for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i)
+      Record.push_back(VE.getAttributeGroupID(A.getSlotAttributes(i)));
 
     Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
     Record.clear();
@@ -255,7 +386,6 @@ static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) {
     unsigned Code = 0;
 
     switch (T->getTypeID()) {
-    default: llvm_unreachable("Unknown type!");
     case Type::VoidTyID:      Code = bitc::TYPE_CODE_VOID;      break;
     case Type::HalfTyID:      Code = bitc::TYPE_CODE_HALF;      break;
     case Type::FloatTyID:     Code = bitc::TYPE_CODE_FLOAT;     break;
@@ -346,30 +476,36 @@ static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) {
   Stream.ExitBlock();
 }
 
-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::DLLImportLinkage:                return 5;
-  case GlobalValue::DLLExportLinkage:                return 6;
-  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::LinkerPrivateLinkage:            return 13;
-  case GlobalValue::LinkerPrivateWeakLinkage:        return 14;
-  case GlobalValue::LinkOnceODRAutoHideLinkage:      return 15;
+static unsigned getEncodedLinkage(const GlobalValue &GV) {
+  switch (GV.getLinkage()) {
+  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");
 }
 
-static unsigned getEncodedVisibility(const GlobalValue *GV) {
-  switch (GV->getVisibility()) {
+static unsigned getEncodedVisibility(const GlobalValue &GV) {
+  switch (GV.getVisibility()) {
   case GlobalValue::DefaultVisibility:   return 0;
   case GlobalValue::HiddenVisibility:    return 1;
   case GlobalValue::ProtectedVisibility: return 2;
@@ -377,8 +513,17 @@ static unsigned getEncodedVisibility(const GlobalValue *GV) {
   llvm_unreachable("Invalid visibility");
 }
 
-static unsigned getEncodedThreadLocalMode(const GlobalVariable *GV) {
-  switch (GV->getThreadLocalMode()) {
+static unsigned getEncodedDLLStorageClass(const GlobalValue &GV) {
+  switch (GV.getDLLStorageClass()) {
+  case GlobalValue::DefaultStorageClass:   return 0;
+  case GlobalValue::DLLImportStorageClass: return 1;
+  case GlobalValue::DLLExportStorageClass: return 2;
+  }
+  llvm_unreachable("Invalid DLL storage class");
+}
+
+static unsigned getEncodedThreadLocalMode(const GlobalValue &GV) {
+  switch (GV.getThreadLocalMode()) {
     case GlobalVariable::NotThreadLocal:         return 0;
     case GlobalVariable::GeneralDynamicTLSModel: return 1;
     case GlobalVariable::LocalDynamicTLSModel:   return 2;
@@ -388,6 +533,37 @@ static unsigned getEncodedThreadLocalMode(const GlobalVariable *GV) {
   llvm_unreachable("Invalid TLS model");
 }
 
+static unsigned getEncodedComdatSelectionKind(const Comdat &C) {
+  switch (C.getSelectionKind()) {
+  case Comdat::Any:
+    return bitc::COMDAT_SELECTION_KIND_ANY;
+  case Comdat::ExactMatch:
+    return bitc::COMDAT_SELECTION_KIND_EXACT_MATCH;
+  case Comdat::Largest:
+    return bitc::COMDAT_SELECTION_KIND_LARGEST;
+  case Comdat::NoDuplicates:
+    return bitc::COMDAT_SELECTION_KIND_NO_DUPLICATES;
+  case Comdat::SameSize:
+    return bitc::COMDAT_SELECTION_KIND_SAME_SIZE;
+  }
+  llvm_unreachable("Invalid selection kind");
+}
+
+static void writeComdats(const ValueEnumerator &VE, BitstreamWriter &Stream) {
+  SmallVector<uint16_t, 64> Vals;
+  for (const Comdat *C : VE.getComdats()) {
+    // COMDAT: [selection_kind, name]
+    Vals.push_back(getEncodedComdatSelectionKind(*C));
+    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);
+    Vals.clear();
+  }
+}
+
 // Emit top-level description of module, including target triple, inline asm,
 // descriptors for global variables, and function prototype info.
 static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
@@ -396,9 +572,9 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   if (!M->getTargetTriple().empty())
     WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
                       0/*TODO*/, Stream);
-  if (!M->getDataLayout().empty())
-    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, M->getDataLayout(),
-                      0/*TODO*/, Stream);
+  const std::string &DL = M->getDataLayoutStr();
+  if (!DL.empty())
+    WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, DL, 0 /*TODO*/, Stream);
   if (!M->getModuleInlineAsm().empty())
     WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
                       0/*TODO*/, Stream);
@@ -409,36 +585,35 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   std::map<std::string, unsigned> GCMap;
   unsigned MaxAlignment = 0;
   unsigned MaxGlobalType = 0;
-  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
-       GV != E; ++GV) {
-    MaxAlignment = std::max(MaxAlignment, GV->getAlignment());
-    MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV->getType()));
-    if (GV->hasSection()) {
+  for (const GlobalValue &GV : M->globals()) {
+    MaxAlignment = std::max(MaxAlignment, GV.getAlignment());
+    MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV.getType()));
+    if (GV.hasSection()) {
       // Give section names unique ID's.
-      unsigned &Entry = SectionMap[GV->getSection()];
+      unsigned &Entry = SectionMap[GV.getSection()];
       if (!Entry) {
-        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV->getSection(),
+        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV.getSection(),
                           0/*TODO*/, Stream);
         Entry = SectionMap.size();
       }
     }
   }
-  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
-    MaxAlignment = std::max(MaxAlignment, F->getAlignment());
-    if (F->hasSection()) {
+  for (const Function &F : *M) {
+    MaxAlignment = std::max(MaxAlignment, F.getAlignment());
+    if (F.hasSection()) {
       // Give section names unique ID's.
-      unsigned &Entry = SectionMap[F->getSection()];
+      unsigned &Entry = SectionMap[F.getSection()];
       if (!Entry) {
-        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
+        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F.getSection(),
                           0/*TODO*/, Stream);
         Entry = SectionMap.size();
       }
     }
-    if (F->hasGC()) {
+    if (F.hasGC()) {
       // Same for GC names.
-      unsigned &Entry = GCMap[F->getGC()];
+      unsigned &Entry = GCMap[F.getGC()];
       if (!Entry) {
-        WriteStringRecord(bitc::MODULE_CODE_GCNAME, F->getGC(),
+        WriteStringRecord(bitc::MODULE_CODE_GCNAME, F.getGC(),
                           0/*TODO*/, Stream);
         Entry = GCMap.size();
       }
@@ -455,7 +630,7 @@ 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 {
@@ -474,26 +649,31 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
 
   // Emit the global variable information.
   SmallVector<unsigned, 64> Vals;
-  for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
-       GV != E; ++GV) {
+  for (const GlobalVariable &GV : M->globals()) {
     unsigned AbbrevToUse = 0;
 
     // GLOBALVAR: [type, isconst, initid,
     //             linkage, alignment, section, visibility, threadlocal,
-    //             unnamed_addr]
-    Vals.push_back(VE.getTypeID(GV->getType()));
-    Vals.push_back(GV->isConstant());
-    Vals.push_back(GV->isDeclaration() ? 0 :
-                   (VE.getValueID(GV->getInitializer()) + 1));
+    //             unnamed_addr, externally_initialized, dllstorageclass,
+    //             comdat]
+    Vals.push_back(VE.getTypeID(GV.getType()));
+    Vals.push_back(GV.isConstant());
+    Vals.push_back(GV.isDeclaration() ? 0 :
+                   (VE.getValueID(GV.getInitializer()) + 1));
     Vals.push_back(getEncodedLinkage(GV));
-    Vals.push_back(Log2_32(GV->getAlignment())+1);
-    Vals.push_back(GV->hasSection() ? SectionMap[GV->getSection()] : 0);
-    if (GV->isThreadLocal() ||
-        GV->getVisibility() != GlobalValue::DefaultVisibility ||
-        GV->hasUnnamedAddr()) {
+    Vals.push_back(Log2_32(GV.getAlignment())+1);
+    Vals.push_back(GV.hasSection() ? SectionMap[GV.getSection()] : 0);
+    if (GV.isThreadLocal() ||
+        GV.getVisibility() != GlobalValue::DefaultVisibility ||
+        GV.hasUnnamedAddr() || GV.isExternallyInitialized() ||
+        GV.getDLLStorageClass() != GlobalValue::DefaultStorageClass ||
+        GV.hasComdat()) {
       Vals.push_back(getEncodedVisibility(GV));
       Vals.push_back(getEncodedThreadLocalMode(GV));
-      Vals.push_back(GV->hasUnnamedAddr());
+      Vals.push_back(GV.hasUnnamedAddr());
+      Vals.push_back(GV.isExternallyInitialized());
+      Vals.push_back(getEncodedDLLStorageClass(GV));
+      Vals.push_back(GV.hasComdat() ? VE.getComdatID(GV.getComdat()) : 0);
     } else {
       AbbrevToUse = SimpleGVarAbbrev;
     }
@@ -503,19 +683,26 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   }
 
   // Emit the function proto information.
-  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
+  for (const Function &F : *M) {
     // FUNCTION:  [type, callingconv, isproto, linkage, paramattrs, alignment,
-    //             section, visibility, gc, unnamed_addr]
-    Vals.push_back(VE.getTypeID(F->getType()));
-    Vals.push_back(F->getCallingConv());
-    Vals.push_back(F->isDeclaration());
+    //             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());
     Vals.push_back(getEncodedLinkage(F));
-    Vals.push_back(VE.getAttributeID(F->getAttributes()));
-    Vals.push_back(Log2_32(F->getAlignment())+1);
-    Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0);
+    Vals.push_back(VE.getAttributeID(F.getAttributes()));
+    Vals.push_back(Log2_32(F.getAlignment())+1);
+    Vals.push_back(F.hasSection() ? SectionMap[F.getSection()] : 0);
     Vals.push_back(getEncodedVisibility(F));
-    Vals.push_back(F->hasGC() ? GCMap[F->getGC()] : 0);
-    Vals.push_back(F->hasUnnamedAddr());
+    Vals.push_back(F.hasGC() ? GCMap[F.getGC()] : 0);
+    Vals.push_back(F.hasUnnamedAddr());
+    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);
@@ -523,13 +710,15 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   }
 
   // Emit the alias information.
-  for (Module::const_alias_iterator AI = M->alias_begin(), E = M->alias_end();
-       AI != E; ++AI) {
+  for (const GlobalAlias &A : M->aliases()) {
     // ALIAS: [alias type, aliasee val#, linkage, visibility]
-    Vals.push_back(VE.getTypeID(AI->getType()));
-    Vals.push_back(VE.getValueID(AI->getAliasee()));
-    Vals.push_back(getEncodedLinkage(AI));
-    Vals.push_back(getEncodedVisibility(AI));
+    Vals.push_back(VE.getTypeID(A.getType()));
+    Vals.push_back(VE.getValueID(A.getAliasee()));
+    Vals.push_back(getEncodedLinkage(A));
+    Vals.push_back(getEncodedVisibility(A));
+    Vals.push_back(getEncodedDLLStorageClass(A));
+    Vals.push_back(getEncodedThreadLocalMode(A));
+    Vals.push_back(A.hasUnnamedAddr());
     unsigned AbbrevToUse = 0;
     Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
     Vals.clear();
@@ -539,18 +728,15 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
 static uint64_t GetOptimizationFlags(const Value *V) {
   uint64_t Flags = 0;
 
-  if (const OverflowingBinaryOperator *OBO =
-        dyn_cast<OverflowingBinaryOperator>(V)) {
+  if (const auto *OBO = dyn_cast<OverflowingBinaryOperator>(V)) {
     if (OBO->hasNoSignedWrap())
       Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
     if (OBO->hasNoUnsignedWrap())
       Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
-  } else if (const PossiblyExactOperator *PEO =
-               dyn_cast<PossiblyExactOperator>(V)) {
+  } else if (const auto *PEO = dyn_cast<PossiblyExactOperator>(V)) {
     if (PEO->isExact())
       Flags |= 1 << bitc::PEO_EXACT;
-  } else if (const FPMathOperator *FPMO =
-             dyn_cast<const FPMathOperator>(V)) {
+  } else if (const auto *FPMO = dyn_cast<FPMathOperator>(V)) {
     if (FPMO->hasUnsafeAlgebra())
       Flags |= FastMathFlags::UnsafeAlgebra;
     if (FPMO->hasNoNaNs())
@@ -566,89 +752,288 @@ static uint64_t GetOptimizationFlags(const Value *V) {
   return Flags;
 }
 
-static void WriteMDNode(const MDNode *N,
-                        const ValueEnumerator &VE,
-                        BitstreamWriter &Stream,
-                        SmallVector<uint64_t, 64> &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 *, const ValueEnumerator &,
+                             BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                             unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDDerivedType(const MDDerivedType *, const ValueEnumerator &,
+                               BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                               unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDCompositeType(const MDCompositeType *,
+                                 const ValueEnumerator &, BitstreamWriter &,
+                                 SmallVectorImpl<uint64_t> &, unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDSubroutineType(const MDSubroutineType *,
+                                  const ValueEnumerator &, BitstreamWriter &,
+                                  SmallVectorImpl<uint64_t> &, unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDFile(const MDFile *, const ValueEnumerator &,
+                        BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                        unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDCompileUnit(const MDCompileUnit *, const ValueEnumerator &,
+                               BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                               unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDSubprogram(const MDSubprogram *, const ValueEnumerator &,
+                              BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                              unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDLexicalBlock(const MDLexicalBlock *, const ValueEnumerator &,
+                                BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                                unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDLexicalBlockFile(const MDLexicalBlockFile *,
+                                    const ValueEnumerator &, BitstreamWriter &,
+                                    SmallVectorImpl<uint64_t> &, unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDNamespace(const MDNamespace *, const ValueEnumerator &,
+                             BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                             unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDTemplateTypeParameter(const MDTemplateTypeParameter *,
+                                         const ValueEnumerator &,
+                                         BitstreamWriter &,
+                                         SmallVectorImpl<uint64_t> &,
+                                         unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDTemplateValueParameter(const MDTemplateValueParameter *,
+                                          const ValueEnumerator &,
+                                          BitstreamWriter &,
+                                          SmallVectorImpl<uint64_t> &,
+                                          unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDGlobalVariable(const MDGlobalVariable *,
+                                  const ValueEnumerator &, BitstreamWriter &,
+                                  SmallVectorImpl<uint64_t> &, unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDLocalVariable(const MDLocalVariable *,
+                                 const ValueEnumerator &, BitstreamWriter &,
+                                 SmallVectorImpl<uint64_t> &, unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDExpression(const MDExpression *, const ValueEnumerator &,
+                              BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                              unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDObjCProperty(const MDObjCProperty *, const ValueEnumerator &,
+                                BitstreamWriter &, SmallVectorImpl<uint64_t> &,
+                                unsigned) {
+  llvm_unreachable("write not implemented");
+}
+static void WriteMDImportedEntity(const MDImportedEntity *,
+                                  const ValueEnumerator &, BitstreamWriter &,
+                                  SmallVectorImpl<uint64_t> &, unsigned) {
+  llvm_unreachable("write not implemented");
+}
+
 static void WriteModuleMetadata(const Module *M,
                                 const ValueEnumerator &VE,
                                 BitstreamWriter &Stream) {
-  const ValueEnumerator::ValueList &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].first)) {
-      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].first)) {
-      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,
@@ -656,16 +1041,16 @@ static void WriteFunctionLocalMetadata(const Function &F,
                                        BitstreamWriter &Stream) {
   bool StartedMetadataBlock = false;
   SmallVector<uint64_t, 64> Record;
-  const SmallVector<const MDNode *, 8> &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();
@@ -680,7 +1065,7 @@ static void WriteMetadataAttachment(const Function &F,
 
   // Write metadata attachments
   // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
-  SmallVector<std::pair<unsigned, MDNode*>, 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();
@@ -695,7 +1080,7 @@ 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();
@@ -735,34 +1120,6 @@ static void emitSignedInt64(SmallVectorImpl<uint64_t> &Vals, uint64_t V) {
     Vals.push_back((-V << 1) | 1);
 }
 
-static void EmitAPInt(SmallVectorImpl<uint64_t> &Vals,
-                      unsigned &Code, unsigned &AbbrevToUse, const APInt &Val,
-                      bool EmitSizeForWideNumbers = false
-                      ) {
-  if (Val.getBitWidth() <= 64) {
-    uint64_t V = Val.getSExtValue();
-    emitSignedInt64(Vals, V);
-    Code = bitc::CST_CODE_INTEGER;
-    AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
-  } else {
-    // Wide integers, > 64 bits in size.
-    // We have an arbitrary precision integer value to write whose
-    // bit width is > 64. However, in canonical unsigned integer
-    // format it is likely that the high bits are going to be zero.
-    // So, we only write the number of active words.
-    unsigned NWords = Val.getActiveWords();
-
-    if (EmitSizeForWideNumbers)
-      Vals.push_back(NWords);
-
-    const uint64_t *RawWords = Val.getRawData();
-    for (unsigned i = 0; i != NWords; ++i) {
-      emitSignedInt64(Vals, RawWords[i]);
-    }
-    Code = bitc::CST_CODE_WIDE_INTEGER;
-  }
-}
-
 static void WriteConstants(unsigned FirstVal, unsigned LastVal,
                            const ValueEnumerator &VE,
                            BitstreamWriter &Stream, bool isGlobal) {
@@ -806,7 +1163,7 @@ static void WriteConstants(unsigned FirstVal, unsigned LastVal,
   SmallVector<uint64_t, 64> Record;
 
   const ValueEnumerator::ValueList &Vals = VE.getValues();
-  Type *LastTy = 0;
+  Type *LastTy = nullptr;
   for (unsigned i = FirstVal; i != LastVal; ++i) {
     const Value *V = Vals[i].first;
     // If we need to switch types, do so now.
@@ -846,7 +1203,23 @@ static void WriteConstants(unsigned FirstVal, unsigned LastVal,
     } else if (isa<UndefValue>(C)) {
       Code = bitc::CST_CODE_UNDEF;
     } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
-      EmitAPInt(Record, Code, AbbrevToUse, IV->getValue());
+      if (IV->getBitWidth() <= 64) {
+        uint64_t V = IV->getSExtValue();
+        emitSignedInt64(Record, V);
+        Code = bitc::CST_CODE_INTEGER;
+        AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
+      } else {                             // Wide integers, > 64 bits in size.
+        // We have an arbitrary precision integer value to write whose
+        // bit width is > 64. However, in canonical unsigned integer
+        // format it is likely that the high bits are going to be zero.
+        // So, we only write the number of active words.
+        unsigned NWords = IV->getValue().getActiveWords();
+        const uint64_t *RawWords = IV->getValue().getRawData();
+        for (unsigned i = 0; i != NWords; ++i) {
+          emitSignedInt64(Record, RawWords[i]);
+        }
+        Code = bitc::CST_CODE_WIDE_INTEGER;
+      }
     } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
       Code = bitc::CST_CODE_FLOAT;
       Type *Ty = CFP->getType();
@@ -960,12 +1333,14 @@ static void WriteConstants(unsigned FirstVal, unsigned LastVal,
         Code = bitc::CST_CODE_CE_EXTRACTELT;
         Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
         Record.push_back(VE.getValueID(C->getOperand(0)));
+        Record.push_back(VE.getTypeID(C->getOperand(1)->getType()));
         Record.push_back(VE.getValueID(C->getOperand(1)));
         break;
       case Instruction::InsertElement:
         Code = bitc::CST_CODE_CE_INSERTELT;
         Record.push_back(VE.getValueID(C->getOperand(0)));
         Record.push_back(VE.getValueID(C->getOperand(1)));
+        Record.push_back(VE.getTypeID(C->getOperand(2)->getType()));
         Record.push_back(VE.getValueID(C->getOperand(2)));
         break;
       case Instruction::ShuffleVector:
@@ -1033,7 +1408,7 @@ static void WriteModuleConstants(const ValueEnumerator &VE,
 /// instruction ID, then it is a forward reference, and it also includes the
 /// type ID.  The value ID that is written is encoded relative to the InstID.
 static bool PushValueAndType(const Value *V, unsigned InstID,
-                             SmallVector<unsigned, 64> &Vals,
+                             SmallVectorImpl<unsigned> &Vals,
                              ValueEnumerator &VE) {
   unsigned ValID = VE.getValueID(V);
   // Make encoding relative to the InstID.
@@ -1048,21 +1423,14 @@ static bool PushValueAndType(const Value *V, unsigned InstID,
 /// pushValue - Like PushValueAndType, but where the type of the value is
 /// omitted (perhaps it was already encoded in an earlier operand).
 static void pushValue(const Value *V, unsigned InstID,
-                      SmallVector<unsigned, 64> &Vals,
+                      SmallVectorImpl<unsigned> &Vals,
                       ValueEnumerator &VE) {
   unsigned ValID = VE.getValueID(V);
   Vals.push_back(InstID - ValID);
 }
 
-static void pushValue64(const Value *V, unsigned InstID,
-                        SmallVector<uint64_t, 128> &Vals,
-                        ValueEnumerator &VE) {
-  uint64_t ValID = VE.getValueID(V);
-  Vals.push_back(InstID - ValID);
-}
-
 static void pushValueSigned(const Value *V, unsigned InstID,
-                            SmallVector<uint64_t, 128> &Vals,
+                            SmallVectorImpl<uint64_t> &Vals,
                             ValueEnumerator &VE) {
   unsigned ValID = VE.getValueID(V);
   int64_t diff = ((int32_t)InstID - (int32_t)ValID);
@@ -1072,7 +1440,7 @@ static void pushValueSigned(const Value *V, unsigned InstID,
 /// WriteInstruction - Emit an instruction to the specified stream.
 static void WriteInstruction(const Instruction &I, unsigned InstID,
                              ValueEnumerator &VE, BitstreamWriter &Stream,
-                             SmallVector<unsigned, 64> &Vals) {
+                             SmallVectorImpl<unsigned> &Vals) {
   unsigned Code = 0;
   unsigned AbbrevToUse = 0;
   VE.setInstructionID(&I);
@@ -1133,13 +1501,13 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
   case Instruction::ExtractElement:
     Code = bitc::FUNC_CODE_INST_EXTRACTELT;
     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
-    pushValue(I.getOperand(1), InstID, Vals, VE);
+    PushValueAndType(I.getOperand(1), InstID, Vals, VE);
     break;
   case Instruction::InsertElement:
     Code = bitc::FUNC_CODE_INST_INSERTELT;
     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
     pushValue(I.getOperand(1), InstID, Vals, VE);
-    pushValue(I.getOperand(2), InstID, Vals, VE);
+    PushValueAndType(I.getOperand(2), InstID, Vals, VE);
     break;
   case Instruction::ShuffleVector:
     Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
@@ -1174,7 +1542,7 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
   case Instruction::Br:
     {
       Code = bitc::FUNC_CODE_INST_BR;
-      BranchInst &II = cast<BranchInst>(I);
+      const BranchInst &II = cast<BranchInst>(I);
       Vals.push_back(VE.getValueID(II.getSuccessor(0)));
       if (II.isConditional()) {
         Vals.push_back(VE.getValueID(II.getSuccessor(1)));
@@ -1184,63 +1552,16 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
     break;
   case Instruction::Switch:
     {
-      // Redefine Vals, since here we need to use 64 bit values
-      // explicitly to store large APInt numbers.
-      SmallVector<uint64_t, 128> Vals64;
-
       Code = bitc::FUNC_CODE_INST_SWITCH;
-      SwitchInst &SI = cast<SwitchInst>(I);
-
-      uint32_t SwitchRecordHeader = SI.hash() | (SWITCH_INST_MAGIC << 16);
-      Vals64.push_back(SwitchRecordHeader);
-
-      Vals64.push_back(VE.getTypeID(SI.getCondition()->getType()));
-      pushValue64(SI.getCondition(), InstID, Vals64, VE);
-      Vals64.push_back(VE.getValueID(SI.getDefaultDest()));
-      Vals64.push_back(SI.getNumCases());
-      for (SwitchInst::CaseIt i = SI.case_begin(), e = SI.case_end();
+      const SwitchInst &SI = cast<SwitchInst>(I);
+      Vals.push_back(VE.getTypeID(SI.getCondition()->getType()));
+      pushValue(SI.getCondition(), InstID, Vals, VE);
+      Vals.push_back(VE.getValueID(SI.getDefaultDest()));
+      for (SwitchInst::ConstCaseIt i = SI.case_begin(), e = SI.case_end();
            i != e; ++i) {
-        IntegersSubset& CaseRanges = i.getCaseValueEx();
-        unsigned Code, Abbrev; // will unused.
-
-        if (CaseRanges.isSingleNumber()) {
-          Vals64.push_back(1/*NumItems = 1*/);
-          Vals64.push_back(true/*IsSingleNumber = true*/);
-          EmitAPInt(Vals64, Code, Abbrev, CaseRanges.getSingleNumber(0), true);
-        } else {
-
-          Vals64.push_back(CaseRanges.getNumItems());
-
-          if (CaseRanges.isSingleNumbersOnly()) {
-            for (unsigned ri = 0, rn = CaseRanges.getNumItems();
-                 ri != rn; ++ri) {
-
-              Vals64.push_back(true/*IsSingleNumber = true*/);
-
-              EmitAPInt(Vals64, Code, Abbrev,
-                        CaseRanges.getSingleNumber(ri), true);
-            }
-          } else
-            for (unsigned ri = 0, rn = CaseRanges.getNumItems();
-                 ri != rn; ++ri) {
-              IntegersSubset::Range r = CaseRanges.getItem(ri);
-              bool IsSingleNumber = CaseRanges.isSingleNumber(ri);
-
-              Vals64.push_back(IsSingleNumber);
-
-              EmitAPInt(Vals64, Code, Abbrev, r.getLow(), true);
-              if (!IsSingleNumber)
-                EmitAPInt(Vals64, Code, Abbrev, r.getHigh(), true);
-            }
-        }
-        Vals64.push_back(VE.getValueID(i.getCaseSuccessor()));
+        Vals.push_back(VE.getValueID(i.getCaseValue()));
+        Vals.push_back(VE.getValueID(i.getCaseSuccessor()));
       }
-
-      Stream.EmitRecord(Code, Vals64, AbbrevToUse);
-
-      // Also do expected action - clear external Vals collection:
-      Vals.clear();
-      return;
     }
     break;
   case Instruction::IndirectBr:
@@ -1321,13 +1642,20 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
     break;
   }
 
-  case Instruction::Alloca:
+  case Instruction::Alloca: {
     Code = bitc::FUNC_CODE_INST_ALLOCA;
     Vals.push_back(VE.getTypeID(I.getType()));
     Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
     Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
-    Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
+    const AllocaInst &AI = cast<AllocaInst>(I);
+    unsigned AlignRecord = Log2_32(AI.getAlignment()) + 1;
+    assert(Log2_32(Value::MaximumAlignment) + 1 < 1 << 5 &&
+           "not enough bits for maximum alignment");
+    assert(AlignRecord < 1 << 5 && "alignment greater than 1 << 64");
+    AlignRecord |= AI.isUsedWithInAlloca() << 5;
+    Vals.push_back(AlignRecord);
     break;
+  }
 
   case Instruction::Load:
     if (cast<LoadInst>(I).isAtomic()) {
@@ -1366,9 +1694,12 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
     pushValue(I.getOperand(2), InstID, Vals, VE);         // newval.
     Vals.push_back(cast<AtomicCmpXchgInst>(I).isVolatile());
     Vals.push_back(GetEncodedOrdering(
-                     cast<AtomicCmpXchgInst>(I).getOrdering()));
+                     cast<AtomicCmpXchgInst>(I).getSuccessOrdering()));
     Vals.push_back(GetEncodedSynchScope(
                      cast<AtomicCmpXchgInst>(I).getSynchScope()));
+    Vals.push_back(GetEncodedOrdering(
+                     cast<AtomicCmpXchgInst>(I).getFailureOrdering()));
+    Vals.push_back(cast<AtomicCmpXchgInst>(I).isWeak());
     break;
   case Instruction::AtomicRMW:
     Code = bitc::FUNC_CODE_INST_ATOMICRMW;
@@ -1394,7 +1725,8 @@ static void WriteInstruction(const Instruction &I, unsigned InstID,
     Code = bitc::FUNC_CODE_INST_CALL;
 
     Vals.push_back(VE.getAttributeID(CI.getAttributes()));
-    Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()));
+    Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()) |
+                   unsigned(CI.isMustTailCall()) << 14);
     PushValueAndType(CI.getCalledValue(), InstID, Vals, VE);  // Callee
 
     // Emit value #'s for the fixed parameters.
@@ -1484,6 +1816,39 @@ static void WriteValueSymbolTable(const ValueSymbolTable &VST,
   Stream.ExitBlock();
 }
 
+static void WriteUseList(ValueEnumerator &VE, UseListOrder &&Order,
+                         BitstreamWriter &Stream) {
+  assert(Order.Shuffle.size() >= 2 && "Shuffle too small");
+  unsigned Code;
+  if (isa<BasicBlock>(Order.V))
+    Code = bitc::USELIST_CODE_BB;
+  else
+    Code = bitc::USELIST_CODE_DEFAULT;
+
+  SmallVector<uint64_t, 64> Record;
+  for (unsigned I : Order.Shuffle)
+    Record.push_back(I);
+  Record.push_back(VE.getValueID(Order.V));
+  Stream.EmitRecord(Code, Record);
+}
+
+static void WriteUseListBlock(const Function *F, ValueEnumerator &VE,
+                              BitstreamWriter &Stream) {
+  auto hasMore = [&]() {
+    return !VE.UseListOrders.empty() && VE.UseListOrders.back().F == F;
+  };
+  if (!hasMore())
+    // Nothing to do.
+    return;
+
+  Stream.EnterSubblock(bitc::USELIST_BLOCK_ID, 3);
+  while (hasMore()) {
+    WriteUseList(VE, std::move(VE.UseListOrders.back()), Stream);
+    VE.UseListOrders.pop_back();
+  }
+  Stream.ExitBlock();
+}
+
 /// WriteFunction - Emit a function body to the module stream.
 static void WriteFunction(const Function &F, ValueEnumerator &VE,
                           BitstreamWriter &Stream) {
@@ -1535,11 +1900,12 @@ 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();
 
@@ -1552,6 +1918,8 @@ static void WriteFunction(const Function &F, ValueEnumerator &VE,
 
   if (NeedsMetadataAttachment)
     WriteMetadataAttachment(F, VE, Stream);
+  if (shouldPreserveBitcodeUseListOrder())
+    WriteUseListBlock(&F, VE, Stream);
   VE.purgeFunction();
   Stream.ExitBlock();
 }
@@ -1717,103 +2085,6 @@ static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
   Stream.ExitBlock();
 }
 
-// Sort the Users based on the order in which the reader parses the bitcode
-// file.
-static bool bitcodereader_order(const User *lhs, const User *rhs) {
-  // TODO: Implement.
-  return true;
-}
-
-static void WriteUseList(const Value *V, const ValueEnumerator &VE,
-                         BitstreamWriter &Stream) {
-
-  // One or zero uses can't get out of order.
-  if (V->use_empty() || V->hasNUses(1))
-    return;
-
-  // Make a copy of the in-memory use-list for sorting.
-  unsigned UseListSize = std::distance(V->use_begin(), V->use_end());
-  SmallVector<const User*, 8> UseList;
-  UseList.reserve(UseListSize);
-  for (Value::const_use_iterator I = V->use_begin(), E = V->use_end();
-       I != E; ++I) {
-    const User *U = *I;
-    UseList.push_back(U);
-  }
-
-  // Sort the copy based on the order read by the BitcodeReader.
-  std::sort(UseList.begin(), UseList.end(), bitcodereader_order);
-
-  // TODO: Generate a diff between the BitcodeWriter in-memory use-list and the
-  // sorted list (i.e., the expected BitcodeReader in-memory use-list).
-
-  // TODO: Emit the USELIST_CODE_ENTRYs.
-}
-
-static void WriteFunctionUseList(const Function *F, ValueEnumerator &VE,
-                                 BitstreamWriter &Stream) {
-  VE.incorporateFunction(*F);
-
-  for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
-       AI != AE; ++AI)
-    WriteUseList(AI, VE, Stream);
-  for (Function::const_iterator BB = F->begin(), FE = F->end(); BB != FE;
-       ++BB) {
-    WriteUseList(BB, VE, Stream);
-    for (BasicBlock::const_iterator II = BB->begin(), IE = BB->end(); II != IE;
-         ++II) {
-      WriteUseList(II, VE, Stream);
-      for (User::const_op_iterator OI = II->op_begin(), E = II->op_end();
-           OI != E; ++OI) {
-        if ((isa<Constant>(*OI) && !isa<GlobalValue>(*OI)) ||
-            isa<InlineAsm>(*OI))
-          WriteUseList(*OI, VE, Stream);
-      }
-    }
-  }
-  VE.purgeFunction();
-}
-
-// Emit use-lists.
-static void WriteModuleUseLists(const Module *M, ValueEnumerator &VE,
-                                BitstreamWriter &Stream) {
-  Stream.EnterSubblock(bitc::USELIST_BLOCK_ID, 3);
-
-  // XXX: this modifies the module, but in a way that should never change the
-  // behavior of any pass or codegen in LLVM. The problem is that GVs may
-  // contain entries in the use_list that do not exist in the Module and are
-  // not stored in the .bc file.
-  for (Module::const_global_iterator I = M->global_begin(), E = M->global_end();
-       I != E; ++I)
-    I->removeDeadConstantUsers();
-
-  // Write the global variables.
-  for (Module::const_global_iterator GI = M->global_begin(),
-         GE = M->global_end(); GI != GE; ++GI) {
-    WriteUseList(GI, VE, Stream);
-
-    // Write the global variable initializers.
-    if (GI->hasInitializer())
-      WriteUseList(GI->getInitializer(), VE, Stream);
-  }
-
-  // Write the functions.
-  for (Module::const_iterator FI = M->begin(), FE = M->end(); FI != FE; ++FI) {
-    WriteUseList(FI, VE, Stream);
-    if (!FI->isDeclaration())
-      WriteFunctionUseList(FI, VE, Stream);
-  }
-
-  // Write the aliases.
-  for (Module::const_alias_iterator AI = M->alias_begin(), AE = M->alias_end();
-       AI != AE; ++AI) {
-    WriteUseList(AI, VE, Stream);
-    WriteUseList(AI->getAliasee(), VE, Stream);
-  }
-
-  Stream.ExitBlock();
-}
-
 /// WriteModule - Emit the specified module to the bitstream.
 static void WriteModule(const Module *M, BitstreamWriter &Stream) {
   Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
@@ -1824,17 +2095,22 @@ static void WriteModule(const Module *M, BitstreamWriter &Stream) {
   Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
 
   // Analyze the module, enumerating globals, functions, etc.
-  ValueEnumerator VE(M);
+  ValueEnumerator VE(*M);
 
   // Emit blockinfo, which defines the standard abbreviations etc.
   WriteBlockInfo(VE, Stream);
 
+  // Emit information about attribute groups.
+  WriteAttributeGroupTable(VE, Stream);
+
   // Emit information about parameter attributes.
   WriteAttributeTable(VE, Stream);
 
   // Emit information describing all of the types in the module.
   WriteTypeTable(VE, Stream);
 
+  writeComdats(VE, Stream);
+
   // Emit top-level description of module, including target triple, inline asm,
   // descriptors for global variables, and function prototype info.
   WriteModuleInfo(M, VE, Stream);
@@ -1851,9 +2127,9 @@ static void WriteModule(const Module *M, BitstreamWriter &Stream) {
   // Emit names for globals/functions etc.
   WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
 
-  // Emit use-lists.
-  if (EnablePreserveUseListOrdering)
-    WriteModuleUseLists(M, VE, Stream);
+  // Emit module-level use-lists.
+  if (shouldPreserveBitcodeUseListOrder())
+    WriteUseListBlock(nullptr, VE, Stream);
 
   // Emit function bodies.
   for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)