vendor/clang/clang-release_60-r321788

46 files changed, 2064 insertions, 789 deletions

diff --git a/lib/AST/Decl.cpp b/lib/AST/Decl.cpp
index 4c1d591b41e9c..918466236bffd 100644
--- a/lib/AST/Decl.cpp
+++ b/lib/AST/Decl.cpp
@@ -779,7 +779,7 @@ LinkageComputer::getLVForNamespaceScopeDecl(const NamedDecl *D,
     // unique-external linkage, it's not legally usable from outside
     // this translation unit.  However, we should use the C linkage
     // rules instead for extern "C" declarations.
-    if (Context.getLangOpts().CPlusPlus && !Function->isInExternCContext()) {
+    if (Context.getLangOpts().CPlusPlus && !isFirstInExternCContext(Function)) {
       // Only look at the type-as-written. Otherwise, deducing the return type
       // of a function could change its linkage.
       QualType TypeAsWritten = Function->getType();
@@ -1165,7 +1165,7 @@ LinkageInfo LinkageComputer::getLVForLocalDecl(const NamedDecl *D,
                                                LVComputationKind computation) {
   if (const auto *Function = dyn_cast<FunctionDecl>(D)) {
     if (Function->isInAnonymousNamespace() &&
-        !Function->isInExternCContext())
+        !isFirstInExternCContext(Function))
       return getInternalLinkageFor(Function);
 
     // This is a "void f();" which got merged with a file static.
@@ -1188,7 +1188,7 @@ LinkageInfo LinkageComputer::getLVForLocalDecl(const NamedDecl *D,
 
   if (const auto *Var = dyn_cast<VarDecl>(D)) {
     if (Var->hasExternalStorage()) {
-      if (Var->isInAnonymousNamespace() && !Var->isInExternCContext())
+      if (Var->isInAnonymousNamespace() && !isFirstInExternCContext(Var))
         return getInternalLinkageFor(Var);
 
       LinkageInfo LV;
diff --git a/lib/Basic/Targets/X86.cpp b/lib/Basic/Targets/X86.cpp
index 3efba26a83731..70433ff066fc0 100644
--- a/lib/Basic/Targets/X86.cpp
+++ b/lib/Basic/Targets/X86.cpp
@@ -139,7 +139,6 @@ bool X86TargetInfo::initFeatureMap(
     setFeatureEnabledImpl(Features, "avx512vnni", true);
     setFeatureEnabledImpl(Features, "avx512vbmi2", true);
     setFeatureEnabledImpl(Features, "avx512vpopcntdq", true);
-    setFeatureEnabledImpl(Features, "clwb", true);
     LLVM_FALLTHROUGH;
   case CK_Cannonlake:
     setFeatureEnabledImpl(Features, "avx512ifma", true);
@@ -152,10 +151,8 @@ bool X86TargetInfo::initFeatureMap(
     setFeatureEnabledImpl(Features, "avx512dq", true);
     setFeatureEnabledImpl(Features, "avx512bw", true);
     setFeatureEnabledImpl(Features, "avx512vl", true);
-    if (Kind == CK_SkylakeServer) {
-      setFeatureEnabledImpl(Features, "pku", true);
-      setFeatureEnabledImpl(Features, "clwb", true);
-    }
+    setFeatureEnabledImpl(Features, "pku", true);
+    setFeatureEnabledImpl(Features, "clwb", true);
     LLVM_FALLTHROUGH;
   case CK_SkylakeClient:
     setFeatureEnabledImpl(Features, "xsavec", true);
diff --git a/lib/Basic/Version.cpp b/lib/Basic/Version.cpp
index a1a67c2bc144d..2dd16da99104c 100644
--- a/lib/Basic/Version.cpp
+++ b/lib/Basic/Version.cpp
@@ -36,7 +36,7 @@ std::string getClangRepositoryPath() {
 
   // If the SVN_REPOSITORY is empty, try to use the SVN keyword. This helps us
   // pick up a tag in an SVN export, for example.
-  StringRef SVNRepository("$URL: https://llvm.org/svn/llvm-project/cfe/trunk/lib/Basic/Version.cpp $");
+  StringRef SVNRepository("$URL: https://llvm.org/svn/llvm-project/cfe/branches/release_60/lib/Basic/Version.cpp $");
   if (URL.empty()) {
     URL = SVNRepository.slice(SVNRepository.find(':'),
                               SVNRepository.find("/lib/Basic"));
diff --git a/lib/CodeGen/CGDeclCXX.cpp b/lib/CodeGen/CGDeclCXX.cpp
index 0429978317021..8c0e01e5624ae 100644
--- a/lib/CodeGen/CGDeclCXX.cpp
+++ b/lib/CodeGen/CGDeclCXX.cpp
@@ -173,10 +173,12 @@ void CodeGenFunction::EmitCXXGlobalVarDeclInit(const VarDecl &D,
   ConstantAddress DeclAddr(DeclPtr, getContext().getDeclAlign(&D));
 
   if (!T->isReferenceType()) {
-    if (getLangOpts().OpenMP && D.hasAttr<OMPThreadPrivateDeclAttr>())
+    if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd &&
+        D.hasAttr<OMPThreadPrivateDeclAttr>()) {
       (void)CGM.getOpenMPRuntime().emitThreadPrivateVarDefinition(
           &D, DeclAddr, D.getAttr<OMPThreadPrivateDeclAttr>()->getLocation(),
           PerformInit, this);
+    }
     if (PerformInit)
       EmitDeclInit(*this, D, DeclAddr);
     if (CGM.isTypeConstant(D.getType(), true))
diff --git a/lib/CodeGen/CGException.cpp b/lib/CodeGen/CGException.cpp
index 1ec084ff3f5b6..1978d2757ac51 100644
--- a/lib/CodeGen/CGException.cpp
+++ b/lib/CodeGen/CGException.cpp
@@ -646,7 +646,7 @@ CodeGenFunction::getMSVCDispatchBlock(EHScopeStack::stable_iterator SI) {
     return DispatchBlock;
 
   if (EHS.getKind() == EHScope::Terminate)
-    DispatchBlock = getTerminateHandler();
+    DispatchBlock = getTerminateFunclet();
   else
     DispatchBlock = createBasicBlock();
   CGBuilderTy Builder(*this, DispatchBlock);
@@ -1334,24 +1334,15 @@ llvm::BasicBlock *CodeGenFunction::getTerminateHandler() {
   if (TerminateHandler)
     return TerminateHandler;
 
-  CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP();
-
   // Set up the terminate handler.  This block is inserted at the very
   // end of the function by FinishFunction.
   TerminateHandler = createBasicBlock("terminate.handler");
+  CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP();
   Builder.SetInsertPoint(TerminateHandler);
+
   llvm::Value *Exn = nullptr;
-  SaveAndRestore<llvm::Instruction *> RestoreCurrentFuncletPad(
-      CurrentFuncletPad);
-  if (EHPersonality::get(*this).usesFuncletPads()) {
-    llvm::Value *ParentPad = CurrentFuncletPad;
-    if (!ParentPad)
-      ParentPad = llvm::ConstantTokenNone::get(CGM.getLLVMContext());
-    CurrentFuncletPad = Builder.CreateCleanupPad(ParentPad);
-  } else {
-    if (getLangOpts().CPlusPlus)
-      Exn = getExceptionFromSlot();
-  }
+  if (getLangOpts().CPlusPlus)
+    Exn = getExceptionFromSlot();
   llvm::CallInst *terminateCall =
       CGM.getCXXABI().emitTerminateForUnexpectedException(*this, Exn);
   terminateCall->setDoesNotReturn();
@@ -1363,6 +1354,42 @@ llvm::BasicBlock *CodeGenFunction::getTerminateHandler() {
   return TerminateHandler;
 }
 
+llvm::BasicBlock *CodeGenFunction::getTerminateFunclet() {
+  assert(EHPersonality::get(*this).usesFuncletPads() &&
+         "use getTerminateLandingPad for non-funclet EH");
+
+  llvm::BasicBlock *&TerminateFunclet = TerminateFunclets[CurrentFuncletPad];
+  if (TerminateFunclet)
+    return TerminateFunclet;
+
+  CGBuilderTy::InsertPoint SavedIP = Builder.saveAndClearIP();
+
+  // Set up the terminate handler.  This block is inserted at the very
+  // end of the function by FinishFunction.
+  TerminateFunclet = createBasicBlock("terminate.handler");
+  Builder.SetInsertPoint(TerminateFunclet);
+
+  // Create the cleanuppad using the current parent pad as its token. Use 'none'
+  // if this is a top-level terminate scope, which is the common case.
+  SaveAndRestore<llvm::Instruction *> RestoreCurrentFuncletPad(
+      CurrentFuncletPad);
+  llvm::Value *ParentPad = CurrentFuncletPad;
+  if (!ParentPad)
+    ParentPad = llvm::ConstantTokenNone::get(CGM.getLLVMContext());
+  CurrentFuncletPad = Builder.CreateCleanupPad(ParentPad);
+
+  // Emit the __std_terminate call.
+  llvm::CallInst *terminateCall =
+      CGM.getCXXABI().emitTerminateForUnexpectedException(*this, nullptr);
+  terminateCall->setDoesNotReturn();
+  Builder.CreateUnreachable();
+
+  // Restore the saved insertion state.
+  Builder.restoreIP(SavedIP);
+
+  return TerminateFunclet;
+}
+
 llvm::BasicBlock *CodeGenFunction::getEHResumeBlock(bool isCleanup) {
   if (EHResumeBlock) return EHResumeBlock;
 
diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index c7dc8337e19e0..3f81be00f32d5 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -2263,9 +2263,11 @@ static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
   Address Addr(V, Alignment);
   // Emit reference to the private copy of the variable if it is an OpenMP
   // threadprivate variable.
-  if (CGF.getLangOpts().OpenMP && VD->hasAttr<OMPThreadPrivateDeclAttr>())
+  if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd &&
+      VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
     return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
                                           E->getExprLoc());
+  }
   LValue LV = VD->getType()->isReferenceType() ?
       CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(),
                                     AlignmentSource::Decl) :
@@ -2446,7 +2448,8 @@ LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
 
 
     // Check for OpenMP threadprivate variables.
-    if (getLangOpts().OpenMP && VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
+    if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd &&
+        VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
       return EmitThreadPrivateVarDeclLValue(
           *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
           E->getExprLoc());
diff --git a/lib/CodeGen/CGOpenMPRuntime.cpp b/lib/CodeGen/CGOpenMPRuntime.cpp
index fa38ee80bf41e..784c90a9eb912 100644
--- a/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -397,6 +397,7 @@ class InlinedOpenMPRegionRAII {
   CodeGenFunction &CGF;
   llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
   FieldDecl *LambdaThisCaptureField = nullptr;
+  const CodeGen::CGBlockInfo *BlockInfo = nullptr;
 
 public:
   /// \brief Constructs region for combined constructs.
@@ -412,6 +413,8 @@ public:
     std::swap(CGF.LambdaCaptureFields, LambdaCaptureFields);
     LambdaThisCaptureField = CGF.LambdaThisCaptureField;
     CGF.LambdaThisCaptureField = nullptr;
+    BlockInfo = CGF.BlockInfo;
+    CGF.BlockInfo = nullptr;
   }
 
   ~InlinedOpenMPRegionRAII() {
@@ -422,6 +425,7 @@ public:
     CGF.CapturedStmtInfo = OldCSI;
     std::swap(CGF.LambdaCaptureFields, LambdaCaptureFields);
     CGF.LambdaThisCaptureField = LambdaThisCaptureField;
+    CGF.BlockInfo = BlockInfo;
   }
 };
 
@@ -8014,3 +8018,299 @@ Address CGOpenMPRuntime::getParameterAddress(CodeGenFunction &CGF,
                                              const VarDecl *TargetParam) const {
   return CGF.GetAddrOfLocalVar(NativeParam);
 }
+
+llvm::Value *CGOpenMPSIMDRuntime::emitParallelOutlinedFunction(
+    const OMPExecutableDirective &D, const VarDecl *ThreadIDVar,
+    OpenMPDirectiveKind InnermostKind, const RegionCodeGenTy &CodeGen) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+llvm::Value *CGOpenMPSIMDRuntime::emitTeamsOutlinedFunction(
+    const OMPExecutableDirective &D, const VarDecl *ThreadIDVar,
+    OpenMPDirectiveKind InnermostKind, const RegionCodeGenTy &CodeGen) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+llvm::Value *CGOpenMPSIMDRuntime::emitTaskOutlinedFunction(
+    const OMPExecutableDirective &D, const VarDecl *ThreadIDVar,
+    const VarDecl *PartIDVar, const VarDecl *TaskTVar,
+    OpenMPDirectiveKind InnermostKind, const RegionCodeGenTy &CodeGen,
+    bool Tied, unsigned &NumberOfParts) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitParallelCall(CodeGenFunction &CGF,
+                                           SourceLocation Loc,
+                                           llvm::Value *OutlinedFn,
+                                           ArrayRef<llvm::Value *> CapturedVars,
+                                           const Expr *IfCond) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitCriticalRegion(
+    CodeGenFunction &CGF, StringRef CriticalName,
+    const RegionCodeGenTy &CriticalOpGen, SourceLocation Loc,
+    const Expr *Hint) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitMasterRegion(CodeGenFunction &CGF,
+                                           const RegionCodeGenTy &MasterOpGen,
+                                           SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTaskyieldCall(CodeGenFunction &CGF,
+                                            SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTaskgroupRegion(
+    CodeGenFunction &CGF, const RegionCodeGenTy &TaskgroupOpGen,
+    SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitSingleRegion(
+    CodeGenFunction &CGF, const RegionCodeGenTy &SingleOpGen,
+    SourceLocation Loc, ArrayRef<const Expr *> CopyprivateVars,
+    ArrayRef<const Expr *> DestExprs, ArrayRef<const Expr *> SrcExprs,
+    ArrayRef<const Expr *> AssignmentOps) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitOrderedRegion(CodeGenFunction &CGF,
+                                            const RegionCodeGenTy &OrderedOpGen,
+                                            SourceLocation Loc,
+                                            bool IsThreads) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitBarrierCall(CodeGenFunction &CGF,
+                                          SourceLocation Loc,
+                                          OpenMPDirectiveKind Kind,
+                                          bool EmitChecks,
+                                          bool ForceSimpleCall) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitForDispatchInit(
+    CodeGenFunction &CGF, SourceLocation Loc,
+    const OpenMPScheduleTy &ScheduleKind, unsigned IVSize, bool IVSigned,
+    bool Ordered, const DispatchRTInput &DispatchValues) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitForStaticInit(
+    CodeGenFunction &CGF, SourceLocation Loc, OpenMPDirectiveKind DKind,
+    const OpenMPScheduleTy &ScheduleKind, const StaticRTInput &Values) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitDistributeStaticInit(
+    CodeGenFunction &CGF, SourceLocation Loc,
+    OpenMPDistScheduleClauseKind SchedKind, const StaticRTInput &Values) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitForOrderedIterationEnd(CodeGenFunction &CGF,
+                                                     SourceLocation Loc,
+                                                     unsigned IVSize,
+                                                     bool IVSigned) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitForStaticFinish(CodeGenFunction &CGF,
+                                              SourceLocation Loc,
+                                              OpenMPDirectiveKind DKind) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+llvm::Value *CGOpenMPSIMDRuntime::emitForNext(CodeGenFunction &CGF,
+                                              SourceLocation Loc,
+                                              unsigned IVSize, bool IVSigned,
+                                              Address IL, Address LB,
+                                              Address UB, Address ST) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitNumThreadsClause(CodeGenFunction &CGF,
+                                               llvm::Value *NumThreads,
+                                               SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitProcBindClause(CodeGenFunction &CGF,
+                                             OpenMPProcBindClauseKind ProcBind,
+                                             SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+Address CGOpenMPSIMDRuntime::getAddrOfThreadPrivate(CodeGenFunction &CGF,
+                                                    const VarDecl *VD,
+                                                    Address VDAddr,
+                                                    SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+llvm::Function *CGOpenMPSIMDRuntime::emitThreadPrivateVarDefinition(
+    const VarDecl *VD, Address VDAddr, SourceLocation Loc, bool PerformInit,
+    CodeGenFunction *CGF) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+Address CGOpenMPSIMDRuntime::getAddrOfArtificialThreadPrivate(
+    CodeGenFunction &CGF, QualType VarType, StringRef Name) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitFlush(CodeGenFunction &CGF,
+                                    ArrayRef<const Expr *> Vars,
+                                    SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTaskCall(CodeGenFunction &CGF, SourceLocation Loc,
+                                       const OMPExecutableDirective &D,
+                                       llvm::Value *TaskFunction,
+                                       QualType SharedsTy, Address Shareds,
+                                       const Expr *IfCond,
+                                       const OMPTaskDataTy &Data) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTaskLoopCall(
+    CodeGenFunction &CGF, SourceLocation Loc, const OMPLoopDirective &D,
+    llvm::Value *TaskFunction, QualType SharedsTy, Address Shareds,
+    const Expr *IfCond, const OMPTaskDataTy &Data) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitReduction(
+    CodeGenFunction &CGF, SourceLocation Loc, ArrayRef<const Expr *> Privates,
+    ArrayRef<const Expr *> LHSExprs, ArrayRef<const Expr *> RHSExprs,
+    ArrayRef<const Expr *> ReductionOps, ReductionOptionsTy Options) {
+  assert(Options.SimpleReduction && "Only simple reduction is expected.");
+  CGOpenMPRuntime::emitReduction(CGF, Loc, Privates, LHSExprs, RHSExprs,
+                                 ReductionOps, Options);
+}
+
+llvm::Value *CGOpenMPSIMDRuntime::emitTaskReductionInit(
+    CodeGenFunction &CGF, SourceLocation Loc, ArrayRef<const Expr *> LHSExprs,
+    ArrayRef<const Expr *> RHSExprs, const OMPTaskDataTy &Data) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTaskReductionFixups(CodeGenFunction &CGF,
+                                                  SourceLocation Loc,
+                                                  ReductionCodeGen &RCG,
+                                                  unsigned N) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+Address CGOpenMPSIMDRuntime::getTaskReductionItem(CodeGenFunction &CGF,
+                                                  SourceLocation Loc,
+                                                  llvm::Value *ReductionsPtr,
+                                                  LValue SharedLVal) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTaskwaitCall(CodeGenFunction &CGF,
+                                           SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitCancellationPointCall(
+    CodeGenFunction &CGF, SourceLocation Loc,
+    OpenMPDirectiveKind CancelRegion) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitCancelCall(CodeGenFunction &CGF,
+                                         SourceLocation Loc, const Expr *IfCond,
+                                         OpenMPDirectiveKind CancelRegion) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTargetOutlinedFunction(
+    const OMPExecutableDirective &D, StringRef ParentName,
+    llvm::Function *&OutlinedFn, llvm::Constant *&OutlinedFnID,
+    bool IsOffloadEntry, const RegionCodeGenTy &CodeGen) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTargetCall(CodeGenFunction &CGF,
+                                         const OMPExecutableDirective &D,
+                                         llvm::Value *OutlinedFn,
+                                         llvm::Value *OutlinedFnID,
+                                         const Expr *IfCond, const Expr *Device,
+                                         ArrayRef<llvm::Value *> CapturedVars) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+bool CGOpenMPSIMDRuntime::emitTargetFunctions(GlobalDecl GD) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+bool CGOpenMPSIMDRuntime::emitTargetGlobalVariable(GlobalDecl GD) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+bool CGOpenMPSIMDRuntime::emitTargetGlobal(GlobalDecl GD) {
+  return false;
+}
+
+llvm::Function *CGOpenMPSIMDRuntime::emitRegistrationFunction() {
+  return nullptr;
+}
+
+void CGOpenMPSIMDRuntime::emitTeamsCall(CodeGenFunction &CGF,
+                                        const OMPExecutableDirective &D,
+                                        SourceLocation Loc,
+                                        llvm::Value *OutlinedFn,
+                                        ArrayRef<llvm::Value *> CapturedVars) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitNumTeamsClause(CodeGenFunction &CGF,
+                                             const Expr *NumTeams,
+                                             const Expr *ThreadLimit,
+                                             SourceLocation Loc) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTargetDataCalls(
+    CodeGenFunction &CGF, const OMPExecutableDirective &D, const Expr *IfCond,
+    const Expr *Device, const RegionCodeGenTy &CodeGen, TargetDataInfo &Info) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitTargetDataStandAloneCall(
+    CodeGenFunction &CGF, const OMPExecutableDirective &D, const Expr *IfCond,
+    const Expr *Device) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitDoacrossInit(CodeGenFunction &CGF,
+                                           const OMPLoopDirective &D) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+void CGOpenMPSIMDRuntime::emitDoacrossOrdered(CodeGenFunction &CGF,
+                                              const OMPDependClause *C) {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+const VarDecl *
+CGOpenMPSIMDRuntime::translateParameter(const FieldDecl *FD,
+                                        const VarDecl *NativeParam) const {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
+Address
+CGOpenMPSIMDRuntime::getParameterAddress(CodeGenFunction &CGF,
+                                         const VarDecl *NativeParam,
+                                         const VarDecl *TargetParam) const {
+  llvm_unreachable("Not supported in SIMD-only mode");
+}
+
diff --git a/lib/CodeGen/CGOpenMPRuntime.h b/lib/CodeGen/CGOpenMPRuntime.h
index 94a143841373a..98e09e09b5ec8 100644
--- a/lib/CodeGen/CGOpenMPRuntime.h
+++ b/lib/CodeGen/CGOpenMPRuntime.h
@@ -1364,6 +1364,571 @@ public:
                            ArrayRef<llvm::Value *> Args = llvm::None) const;
 };
 
+/// Class supports emissionof SIMD-only code.
+class CGOpenMPSIMDRuntime final : public CGOpenMPRuntime {
+public:
+  explicit CGOpenMPSIMDRuntime(CodeGenModule &CGM) : CGOpenMPRuntime(CGM) {}
+  ~CGOpenMPSIMDRuntime() override {}
+
+  /// \brief Emits outlined function for the specified OpenMP parallel directive
+  /// \a D. This outlined function has type void(*)(kmp_int32 *ThreadID,
+  /// kmp_int32 BoundID, struct context_vars*).
+  /// \param D OpenMP directive.
+  /// \param ThreadIDVar Variable for thread id in the current OpenMP region.
+  /// \param InnermostKind Kind of innermost directive (for simple directives it
+  /// is a directive itself, for combined - its innermost directive).
+  /// \param CodeGen Code generation sequence for the \a D directive.
+  llvm::Value *
+  emitParallelOutlinedFunction(const OMPExecutableDirective &D,
+                               const VarDecl *ThreadIDVar,
+                               OpenMPDirectiveKind InnermostKind,
+                               const RegionCodeGenTy &CodeGen) override;
+
+  /// \brief Emits outlined function for the specified OpenMP teams directive
+  /// \a D. This outlined function has type void(*)(kmp_int32 *ThreadID,
+  /// kmp_int32 BoundID, struct context_vars*).
+  /// \param D OpenMP directive.
+  /// \param ThreadIDVar Variable for thread id in the current OpenMP region.
+  /// \param InnermostKind Kind of innermost directive (for simple directives it
+  /// is a directive itself, for combined - its innermost directive).
+  /// \param CodeGen Code generation sequence for the \a D directive.
+  llvm::Value *
+  emitTeamsOutlinedFunction(const OMPExecutableDirective &D,
+                            const VarDecl *ThreadIDVar,
+                            OpenMPDirectiveKind InnermostKind,
+                            const RegionCodeGenTy &CodeGen) override;
+
+  /// \brief Emits outlined function for the OpenMP task directive \a D. This
+  /// outlined function has type void(*)(kmp_int32 ThreadID, struct task_t*
+  /// TaskT).
+  /// \param D OpenMP directive.
+  /// \param ThreadIDVar Variable for thread id in the current OpenMP region.
+  /// \param PartIDVar Variable for partition id in the current OpenMP untied
+  /// task region.
+  /// \param TaskTVar Variable for task_t argument.
+  /// \param InnermostKind Kind of innermost directive (for simple directives it
+  /// is a directive itself, for combined - its innermost directive).
+  /// \param CodeGen Code generation sequence for the \a D directive.
+  /// \param Tied true if task is generated for tied task, false otherwise.
+  /// \param NumberOfParts Number of parts in untied task. Ignored for tied
+  /// tasks.
+  ///
+  llvm::Value *emitTaskOutlinedFunction(
+      const OMPExecutableDirective &D, const VarDecl *ThreadIDVar,
+      const VarDecl *PartIDVar, const VarDecl *TaskTVar,
+      OpenMPDirectiveKind InnermostKind, const RegionCodeGenTy &CodeGen,
+      bool Tied, unsigned &NumberOfParts) override;
+
+  /// \brief Emits code for parallel or serial call of the \a OutlinedFn with
+  /// variables captured in a record which address is stored in \a
+  /// CapturedStruct.
+  /// \param OutlinedFn Outlined function to be run in parallel threads. Type of
+  /// this function is void(*)(kmp_int32 *, kmp_int32, struct context_vars*).
+  /// \param CapturedVars A pointer to the record with the references to
+  /// variables used in \a OutlinedFn function.
+  /// \param IfCond Condition in the associated 'if' clause, if it was
+  /// specified, nullptr otherwise.
+  ///
+  void emitParallelCall(CodeGenFunction &CGF, SourceLocation Loc,
+                        llvm::Value *OutlinedFn,
+                        ArrayRef<llvm::Value *> CapturedVars,
+                        const Expr *IfCond) override;
+
+  /// \brief Emits a critical region.
+  /// \param CriticalName Name of the critical region.
+  /// \param CriticalOpGen Generator for the statement associated with the given
+  /// critical region.
+  /// \param Hint Value of the 'hint' clause (optional).
+  void emitCriticalRegion(CodeGenFunction &CGF, StringRef CriticalName,
+                          const RegionCodeGenTy &CriticalOpGen,
+                          SourceLocation Loc,
+                          const Expr *Hint = nullptr) override;
+
+  /// \brief Emits a master region.
+  /// \param MasterOpGen Generator for the statement associated with the given
+  /// master region.
+  void emitMasterRegion(CodeGenFunction &CGF,
+                        const RegionCodeGenTy &MasterOpGen,
+                        SourceLocation Loc) override;
+
+  /// \brief Emits code for a taskyield directive.
+  void emitTaskyieldCall(CodeGenFunction &CGF, SourceLocation Loc) override;
+
+  /// \brief Emit a taskgroup region.
+  /// \param TaskgroupOpGen Generator for the statement associated with the
+  /// given taskgroup region.
+  void emitTaskgroupRegion(CodeGenFunction &CGF,
+                           const RegionCodeGenTy &TaskgroupOpGen,
+                           SourceLocation Loc) override;
+
+  /// \brief Emits a single region.
+  /// \param SingleOpGen Generator for the statement associated with the given
+  /// single region.
+  void emitSingleRegion(CodeGenFunction &CGF,
+                        const RegionCodeGenTy &SingleOpGen, SourceLocation Loc,
+                        ArrayRef<const Expr *> CopyprivateVars,
+                        ArrayRef<const Expr *> DestExprs,
+                        ArrayRef<const Expr *> SrcExprs,
+                        ArrayRef<const Expr *> AssignmentOps) override;
+
+  /// \brief Emit an ordered region.
+  /// \param OrderedOpGen Generator for the statement associated with the given
+  /// ordered region.
+  void emitOrderedRegion(CodeGenFunction &CGF,
+                         const RegionCodeGenTy &OrderedOpGen,
+                         SourceLocation Loc, bool IsThreads) override;
+
+  /// \brief Emit an implicit/explicit barrier for OpenMP threads.
+  /// \param Kind Directive for which this implicit barrier call must be
+  /// generated. Must be OMPD_barrier for explicit barrier generation.
+  /// \param EmitChecks true if need to emit checks for cancellation barriers.
+  /// \param ForceSimpleCall true simple barrier call must be emitted, false if
+  /// runtime class decides which one to emit (simple or with cancellation
+  /// checks).
+  ///
+  void emitBarrierCall(CodeGenFunction &CGF, SourceLocation Loc,
+                       OpenMPDirectiveKind Kind, bool EmitChecks = true,
+                       bool ForceSimpleCall = false) override;
+
+  /// This is used for non static scheduled types and when the ordered
+  /// clause is present on the loop construct.
+  /// Depending on the loop schedule, it is necessary to call some runtime
+  /// routine before start of the OpenMP loop to get the loop upper / lower
+  /// bounds \a LB and \a UB and stride \a ST.
+  ///
+  /// \param CGF Reference to current CodeGenFunction.
+  /// \param Loc Clang source location.
+  /// \param ScheduleKind Schedule kind, specified by the 'schedule' clause.
+  /// \param IVSize Size of the iteration variable in bits.
+  /// \param IVSigned Sign of the iteration variable.
+  /// \param Ordered true if loop is ordered, false otherwise.
+  /// \param DispatchValues struct containing llvm values for lower bound, upper
+  /// bound, and chunk expression.
+  /// For the default (nullptr) value, the chunk 1 will be used.
+  ///
+  void emitForDispatchInit(CodeGenFunction &CGF, SourceLocation Loc,
+                           const OpenMPScheduleTy &ScheduleKind,
+                           unsigned IVSize, bool IVSigned, bool Ordered,
+                           const DispatchRTInput &DispatchValues) override;
+
+  /// \brief Call the appropriate runtime routine to initialize it before start
+  /// of loop.
+  ///
+  /// This is used only in case of static schedule, when the user did not
+  /// specify a ordered clause on the loop construct.
+  /// Depending on the loop schedule, it is necessary to call some runtime
+  /// routine before start of the OpenMP loop to get the loop upper / lower
+  /// bounds LB and UB and stride ST.
+  ///
+  /// \param CGF Reference to current CodeGenFunction.
+  /// \param Loc Clang source location.
+  /// \param DKind Kind of the directive.
+  /// \param ScheduleKind Schedule kind, specified by the 'schedule' clause.
+  /// \param Values Input arguments for the construct.
+  ///
+  void emitForStaticInit(CodeGenFunction &CGF, SourceLocation Loc,
+                         OpenMPDirectiveKind DKind,
+                         const OpenMPScheduleTy &ScheduleKind,
+                         const StaticRTInput &Values) override;
+
+  ///
+  /// \param CGF Reference to current CodeGenFunction.
+  /// \param Loc Clang source location.
+  /// \param SchedKind Schedule kind, specified by the 'dist_schedule' clause.
+  /// \param Values Input arguments for the construct.
+  ///
+  void emitDistributeStaticInit(CodeGenFunction &CGF, SourceLocation Loc,
+                                OpenMPDistScheduleClauseKind SchedKind,
+                                const StaticRTInput &Values) override;
+
+  /// \brief Call the appropriate runtime routine to notify that we finished
+  /// iteration of the ordered loop with the dynamic scheduling.
+  ///
+  /// \param CGF Reference to current CodeGenFunction.
+  /// \param Loc Clang source location.
+  /// \param IVSize Size of the iteration variable in bits.
+  /// \param IVSigned Sign of the iteration variable.
+  ///
+  void emitForOrderedIterationEnd(CodeGenFunction &CGF, SourceLocation Loc,
+                                  unsigned IVSize, bool IVSigned) override;
+
+  /// \brief Call the appropriate runtime routine to notify that we finished
+  /// all the work with current loop.
+  ///
+  /// \param CGF Reference to current CodeGenFunction.
+  /// \param Loc Clang source location.
+  /// \param DKind Kind of the directive for which the static finish is emitted.
+  ///
+  void emitForStaticFinish(CodeGenFunction &CGF, SourceLocation Loc,
+                           OpenMPDirectiveKind DKind) override;
+
+  /// Call __kmpc_dispatch_next(
+  ///          ident_t *loc, kmp_int32 tid, kmp_int32 *p_lastiter,
+  ///          kmp_int[32|64] *p_lower, kmp_int[32|64] *p_upper,
+  ///          kmp_int[32|64] *p_stride);
+  /// \param IVSize Size of the iteration variable in bits.
+  /// \param IVSigned Sign of the iteration variable.
+  /// \param IL Address of the output variable in which the flag of the
+  /// last iteration is returned.
+  /// \param LB Address of the output variable in which the lower iteration
+  /// number is returned.
+  /// \param UB Address of the output variable in which the upper iteration
+  /// number is returned.
+  /// \param ST Address of the output variable in which the stride value is
+  /// returned.
+  llvm::Value *emitForNext(CodeGenFunction &CGF, SourceLocation Loc,
+                           unsigned IVSize, bool IVSigned, Address IL,
+                           Address LB, Address UB, Address ST) override;
+
+  /// \brief Emits call to void __kmpc_push_num_threads(ident_t *loc, kmp_int32
+  /// global_tid, kmp_int32 num_threads) to generate code for 'num_threads'
+  /// clause.
+  /// \param NumThreads An integer value of threads.
+  void emitNumThreadsClause(CodeGenFunction &CGF, llvm::Value *NumThreads,
+                            SourceLocation Loc) override;
+
+  /// \brief Emit call to void __kmpc_push_proc_bind(ident_t *loc, kmp_int32
+  /// global_tid, int proc_bind) to generate code for 'proc_bind' clause.
+  void emitProcBindClause(CodeGenFunction &CGF,
+                          OpenMPProcBindClauseKind ProcBind,
+                          SourceLocation Loc) override;
+
+  /// \brief Returns address of the threadprivate variable for the current
+  /// thread.
+  /// \param VD Threadprivate variable.
+  /// \param VDAddr Address of the global variable \a VD.
+  /// \param Loc Location of the reference to threadprivate var.
+  /// \return Address of the threadprivate variable for the current thread.
+  Address getAddrOfThreadPrivate(CodeGenFunction &CGF, const VarDecl *VD,
+                                 Address VDAddr, SourceLocation Loc) override;
+
+  /// \brief Emit a code for initialization of threadprivate variable. It emits
+  /// a call to runtime library which adds initial value to the newly created
+  /// threadprivate variable (if it is not constant) and registers destructor
+  /// for the variable (if any).
+  /// \param VD Threadprivate variable.
+  /// \param VDAddr Address of the global variable \a VD.
+  /// \param Loc Location of threadprivate declaration.
+  /// \param PerformInit true if initialization expression is not constant.
+  llvm::Function *
+  emitThreadPrivateVarDefinition(const VarDecl *VD, Address VDAddr,
+                                 SourceLocation Loc, bool PerformInit,
+                                 CodeGenFunction *CGF = nullptr) override;
+
+  /// Creates artificial threadprivate variable with name \p Name and type \p
+  /// VarType.
+  /// \param VarType Type of the artificial threadprivate variable.
+  /// \param Name Name of the artificial threadprivate variable.
+  Address getAddrOfArtificialThreadPrivate(CodeGenFunction &CGF,
+                                           QualType VarType,
+                                           StringRef Name) override;
+
+  /// \brief Emit flush of the variables specified in 'omp flush' directive.
+  /// \param Vars List of variables to flush.
+  void emitFlush(CodeGenFunction &CGF, ArrayRef<const Expr *> Vars,
+                 SourceLocation Loc) override;
+
+  /// \brief Emit task region for the task directive. The task region is
+  /// emitted in several steps:
+  /// 1. Emit a call to kmp_task_t *__kmpc_omp_task_alloc(ident_t *, kmp_int32
+  /// gtid, kmp_int32 flags, size_t sizeof_kmp_task_t, size_t sizeof_shareds,
+  /// kmp_routine_entry_t *task_entry). Here task_entry is a pointer to the
+  /// function:
+  /// kmp_int32 .omp_task_entry.(kmp_int32 gtid, kmp_task_t *tt) {
+  ///   TaskFunction(gtid, tt->part_id, tt->shareds);
+  ///   return 0;
+  /// }
+  /// 2. Copy a list of shared variables to field shareds of the resulting
+  /// structure kmp_task_t returned by the previous call (if any).
+  /// 3. Copy a pointer to destructions function to field destructions of the
+  /// resulting structure kmp_task_t.
+  /// 4. Emit a call to kmp_int32 __kmpc_omp_task(ident_t *, kmp_int32 gtid,
+  /// kmp_task_t *new_task), where new_task is a resulting structure from
+  /// previous items.
+  /// \param D Current task directive.
+  /// \param TaskFunction An LLVM function with type void (*)(i32 /*gtid*/, i32
+  /// /*part_id*/, captured_struct */*__context*/);
+  /// \param SharedsTy A type which contains references the shared variables.
+  /// \param Shareds Context with the list of shared variables from the \p
+  /// TaskFunction.
+  /// \param IfCond Not a nullptr if 'if' clause was specified, nullptr
+  /// otherwise.
+  /// \param Data Additional data for task generation like tiednsee, final
+  /// state, list of privates etc.
+  void emitTaskCall(CodeGenFunction &CGF, SourceLocation Loc,
+                    const OMPExecutableDirective &D, llvm::Value *TaskFunction,
+                    QualType SharedsTy, Address Shareds, const Expr *IfCond,
+                    const OMPTaskDataTy &Data) override;
+
+  /// Emit task region for the taskloop directive. The taskloop region is
+  /// emitted in several steps:
+  /// 1. Emit a call to kmp_task_t *__kmpc_omp_task_alloc(ident_t *, kmp_int32
+  /// gtid, kmp_int32 flags, size_t sizeof_kmp_task_t, size_t sizeof_shareds,
+  /// kmp_routine_entry_t *task_entry). Here task_entry is a pointer to the
+  /// function:
+  /// kmp_int32 .omp_task_entry.(kmp_int32 gtid, kmp_task_t *tt) {
+  ///   TaskFunction(gtid, tt->part_id, tt->shareds);
+  ///   return 0;
+  /// }
+  /// 2. Copy a list of shared variables to field shareds of the resulting
+  /// structure kmp_task_t returned by the previous call (if any).
+  /// 3. Copy a pointer to destructions function to field destructions of the
+  /// resulting structure kmp_task_t.
+  /// 4. Emit a call to void __kmpc_taskloop(ident_t *loc, int gtid, kmp_task_t
+  /// *task, int if_val, kmp_uint64 *lb, kmp_uint64 *ub, kmp_int64 st, int
+  /// nogroup, int sched, kmp_uint64 grainsize, void *task_dup ), where new_task
+  /// is a resulting structure from
+  /// previous items.
+  /// \param D Current task directive.
+  /// \param TaskFunction An LLVM function with type void (*)(i32 /*gtid*/, i32
+  /// /*part_id*/, captured_struct */*__context*/);
+  /// \param SharedsTy A type which contains references the shared variables.
+  /// \param Shareds Context with the list of shared variables from the \p
+  /// TaskFunction.
+  /// \param IfCond Not a nullptr if 'if' clause was specified, nullptr
+  /// otherwise.
+  /// \param Data Additional data for task generation like tiednsee, final
+  /// state, list of privates etc.
+  void emitTaskLoopCall(CodeGenFunction &CGF, SourceLocation Loc,
+                        const OMPLoopDirective &D, llvm::Value *TaskFunction,
+                        QualType SharedsTy, Address Shareds, const Expr *IfCond,
+                        const OMPTaskDataTy &Data) override;
+
+  /// \brief Emit a code for reduction clause. Next code should be emitted for
+  /// reduction:
+  /// \code
+  ///
+  /// static kmp_critical_name lock = { 0 };
+  ///
+  /// void reduce_func(void *lhs[<n>], void *rhs[<n>]) {
+  ///  ...
+  ///  *(Type<i>*)lhs[i] = RedOp<i>(*(Type<i>*)lhs[i], *(Type<i>*)rhs[i]);
+  ///  ...
+  /// }
+  ///
+  /// ...
+  /// void *RedList[<n>] = {&<RHSExprs>[0], ..., &<RHSExprs>[<n>-1]};
+  /// switch (__kmpc_reduce{_nowait}(<loc>, <gtid>, <n>, sizeof(RedList),
+  /// RedList, reduce_func, &<lock>)) {
+  /// case 1:
+  ///  ...
+  ///  <LHSExprs>[i] = RedOp<i>(*<LHSExprs>[i], *<RHSExprs>[i]);
+  ///  ...
+  /// __kmpc_end_reduce{_nowait}(<loc>, <gtid>, &<lock>);
+  /// break;
+  /// case 2:
+  ///  ...
+  ///  Atomic(<LHSExprs>[i] = RedOp<i>(*<LHSExprs>[i], *<RHSExprs>[i]));
+  ///  ...
+  /// break;
+  /// default:;
+  /// }
+  /// \endcode
+  ///
+  /// \param Privates List of private copies for original reduction arguments.
+  /// \param LHSExprs List of LHS in \a ReductionOps reduction operations.
+  /// \param RHSExprs List of RHS in \a ReductionOps reduction operations.
+  /// \param ReductionOps List of reduction operations in form 'LHS binop RHS'
+  /// or 'operator binop(LHS, RHS)'.
+  /// \param Options List of options for reduction codegen:
+  ///     WithNowait true if parent directive has also nowait clause, false
+  ///     otherwise.
+  ///     SimpleReduction Emit reduction operation only. Used for omp simd
+  ///     directive on the host.
+  ///     ReductionKind The kind of reduction to perform.
+  void emitReduction(CodeGenFunction &CGF, SourceLocation Loc,
+                     ArrayRef<const Expr *> Privates,
+                     ArrayRef<const Expr *> LHSExprs,
+                     ArrayRef<const Expr *> RHSExprs,
+                     ArrayRef<const Expr *> ReductionOps,
+                     ReductionOptionsTy Options) override;
+
+  /// Emit a code for initialization of task reduction clause. Next code
+  /// should be emitted for reduction:
+  /// \code
+  ///
+  /// _task_red_item_t red_data[n];
+  /// ...
+  /// red_data[i].shar = &origs[i];
+  /// red_data[i].size = sizeof(origs[i]);
+  /// red_data[i].f_init = (void*)RedInit<i>;
+  /// red_data[i].f_fini = (void*)RedDest<i>;
+  /// red_data[i].f_comb = (void*)RedOp<i>;
+  /// red_data[i].flags = <Flag_i>;
+  /// ...
+  /// void* tg1 = __kmpc_task_reduction_init(gtid, n, red_data);
+  /// \endcode
+  ///
+  /// \param LHSExprs List of LHS in \a Data.ReductionOps reduction operations.
+  /// \param RHSExprs List of RHS in \a Data.ReductionOps reduction operations.
+  /// \param Data Additional data for task generation like tiedness, final
+  /// state, list of privates, reductions etc.
+  llvm::Value *emitTaskReductionInit(CodeGenFunction &CGF, SourceLocation Loc,
+                                     ArrayRef<const Expr *> LHSExprs,
+                                     ArrayRef<const Expr *> RHSExprs,
+                                     const OMPTaskDataTy &Data) override;
+
+  /// Required to resolve existing problems in the runtime. Emits threadprivate
+  /// variables to store the size of the VLAs/array sections for
+  /// initializer/combiner/finalizer functions + emits threadprivate variable to
+  /// store the pointer to the original reduction item for the custom
+  /// initializer defined by declare reduction construct.
+  /// \param RCG Allows to reuse an existing data for the reductions.
+  /// \param N Reduction item for which fixups must be emitted.
+  void emitTaskReductionFixups(CodeGenFunction &CGF, SourceLocation Loc,
+                               ReductionCodeGen &RCG, unsigned N) override;
+
+  /// Get the address of `void *` type of the privatue copy of the reduction
+  /// item specified by the \p SharedLVal.
+  /// \param ReductionsPtr Pointer to the reduction data returned by the
+  /// emitTaskReductionInit function.
+  /// \param SharedLVal Address of the original reduction item.
+  Address getTaskReductionItem(CodeGenFunction &CGF, SourceLocation Loc,
+                               llvm::Value *ReductionsPtr,
+                               LValue SharedLVal) override;
+
+  /// \brief Emit code for 'taskwait' directive.
+  void emitTaskwaitCall(CodeGenFunction &CGF, SourceLocation Loc) override;
+
+  /// \brief Emit code for 'cancellation point' construct.
+  /// \param CancelRegion Region kind for which the cancellation point must be
+  /// emitted.
+  ///
+  void emitCancellationPointCall(CodeGenFunction &CGF, SourceLocation Loc,
+                                 OpenMPDirectiveKind CancelRegion) override;
+
+  /// \brief Emit code for 'cancel' construct.
+  /// \param IfCond Condition in the associated 'if' clause, if it was
+  /// specified, nullptr otherwise.
+  /// \param CancelRegion Region kind for which the cancel must be emitted.
+  ///
+  void emitCancelCall(CodeGenFunction &CGF, SourceLocation Loc,
+                      const Expr *IfCond,
+                      OpenMPDirectiveKind CancelRegion) override;
+
+  /// \brief Emit outilined function for 'target' directive.
+  /// \param D Directive to emit.
+  /// \param ParentName Name of the function that encloses the target region.
+  /// \param OutlinedFn Outlined function value to be defined by this call.
+  /// \param OutlinedFnID Outlined function ID value to be defined by this call.
+  /// \param IsOffloadEntry True if the outlined function is an offload entry.
+  /// \param CodeGen Code generation sequence for the \a D directive.
+  /// An outlined function may not be an entry if, e.g. the if clause always
+  /// evaluates to false.
+  void emitTargetOutlinedFunction(const OMPExecutableDirective &D,
+                                  StringRef ParentName,
+                                  llvm::Function *&OutlinedFn,
+                                  llvm::Constant *&OutlinedFnID,
+                                  bool IsOffloadEntry,
+                                  const RegionCodeGenTy &CodeGen) override;
+
+  /// \brief Emit the target offloading code associated with \a D. The emitted
+  /// code attempts offloading the execution to the device, an the event of
+  /// a failure it executes the host version outlined in \a OutlinedFn.
+  /// \param D Directive to emit.
+  /// \param OutlinedFn Host version of the code to be offloaded.
+  /// \param OutlinedFnID ID of host version of the code to be offloaded.
+  /// \param IfCond Expression evaluated in if clause associated with the target
+  /// directive, or null if no if clause is used.
+  /// \param Device Expression evaluated in device clause associated with the
+  /// target directive, or null if no device clause is used.
+  /// \param CapturedVars Values captured in the current region.
+  void emitTargetCall(CodeGenFunction &CGF, const OMPExecutableDirective &D,
+                      llvm::Value *OutlinedFn, llvm::Value *OutlinedFnID,
+                      const Expr *IfCond, const Expr *Device,
+                      ArrayRef<llvm::Value *> CapturedVars) override;
+
+  /// \brief Emit the target regions enclosed in \a GD function definition or
+  /// the function itself in case it is a valid device function. Returns true if
+  /// \a GD was dealt with successfully.
+  /// \param GD Function to scan.
+  bool emitTargetFunctions(GlobalDecl GD) override;
+
+  /// \brief Emit the global variable if it is a valid device global variable.
+  /// Returns true if \a GD was dealt with successfully.
+  /// \param GD Variable declaration to emit.
+  bool emitTargetGlobalVariable(GlobalDecl GD) override;
+
+  /// \brief Emit the global \a GD if it is meaningful for the target. Returns
+  /// if it was emitted successfully.
+  /// \param GD Global to scan.
+  bool emitTargetGlobal(GlobalDecl GD) override;
+
+  /// \brief Creates the offloading descriptor in the event any target region
+  /// was emitted in the current module and return the function that registers
+  /// it.
+  llvm::Function *emitRegistrationFunction() override;
+
+  /// \brief Emits code for teams call of the \a OutlinedFn with
+  /// variables captured in a record which address is stored in \a
+  /// CapturedStruct.
+  /// \param OutlinedFn Outlined function to be run by team masters. Type of
+  /// this function is void(*)(kmp_int32 *, kmp_int32, struct context_vars*).
+  /// \param CapturedVars A pointer to the record with the references to
+  /// variables used in \a OutlinedFn function.
+  ///
+  void emitTeamsCall(CodeGenFunction &CGF, const OMPExecutableDirective &D,
+                     SourceLocation Loc, llvm::Value *OutlinedFn,
+                     ArrayRef<llvm::Value *> CapturedVars) override;
+
+  /// \brief Emits call to void __kmpc_push_num_teams(ident_t *loc, kmp_int32
+  /// global_tid, kmp_int32 num_teams, kmp_int32 thread_limit) to generate code
+  /// for num_teams clause.
+  /// \param NumTeams An integer expression of teams.
+  /// \param ThreadLimit An integer expression of threads.
+  void emitNumTeamsClause(CodeGenFunction &CGF, const Expr *NumTeams,
+                          const Expr *ThreadLimit, SourceLocation Loc) override;
+
+  /// \brief Emit the target data mapping code associated with \a D.
+  /// \param D Directive to emit.
+  /// \param IfCond Expression evaluated in if clause associated with the
+  /// target directive, or null if no device clause is used.
+  /// \param Device Expression evaluated in device clause associated with the
+  /// target directive, or null if no device clause is used.
+  /// \param Info A record used to store information that needs to be preserved
+  /// until the region is closed.
+  void emitTargetDataCalls(CodeGenFunction &CGF,
+                           const OMPExecutableDirective &D, const Expr *IfCond,
+                           const Expr *Device, const RegionCodeGenTy &CodeGen,
+                           TargetDataInfo &Info) override;
+
+  /// \brief Emit the data mapping/movement code associated with the directive
+  /// \a D that should be of the form 'target [{enter|exit} data | update]'.
+  /// \param D Directive to emit.
+  /// \param IfCond Expression evaluated in if clause associated with the target
+  /// directive, or null if no if clause is used.
+  /// \param Device Expression evaluated in device clause associated with the
+  /// target directive, or null if no device clause is used.
+  void emitTargetDataStandAloneCall(CodeGenFunction &CGF,
+                                    const OMPExecutableDirective &D,
+                                    const Expr *IfCond,
+                                    const Expr *Device) override;
+
+  /// Emit initialization for doacross loop nesting support.
+  /// \param D Loop-based construct used in doacross nesting construct.
+  void emitDoacrossInit(CodeGenFunction &CGF,
+                        const OMPLoopDirective &D) override;
+
+  /// Emit code for doacross ordered directive with 'depend' clause.
+  /// \param C 'depend' clause with 'sink|source' dependency kind.
+  void emitDoacrossOrdered(CodeGenFunction &CGF,
+                           const OMPDependClause *C) override;
+
+  /// Translates the native parameter of outlined function if this is required
+  /// for target.
+  /// \param FD Field decl from captured record for the paramater.
+  /// \param NativeParam Parameter itself.
+  const VarDecl *translateParameter(const FieldDecl *FD,
+                                    const VarDecl *NativeParam) const override;
+
+  /// Gets the address of the native argument basing on the address of the
+  /// target-specific parameter.
+  /// \param NativeParam Parameter itself.
+  /// \param TargetParam Corresponding target-specific parameter.
+  Address getParameterAddress(CodeGenFunction &CGF, const VarDecl *NativeParam,
+                              const VarDecl *TargetParam) const override;
+};
+
 } // namespace CodeGen
 } // namespace clang
 
diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp
index 91fa49a46ef1e..97e35e2b6e8df 100644
--- a/lib/CodeGen/CGStmt.cpp
+++ b/lib/CodeGen/CGStmt.cpp
@@ -74,6 +74,15 @@ void CodeGenFunction::EmitStmt(const Stmt *S, ArrayRef<const Attr *> Attrs) {
   // Generate a stoppoint if we are emitting debug info.
   EmitStopPoint(S);
 
+  // Ignore all OpenMP directives except for simd if OpenMP with Simd is
+  // enabled.
+  if (getLangOpts().OpenMP && getLangOpts().OpenMPSimd) {
+    if (const auto *D = dyn_cast<OMPExecutableDirective>(S)) {
+      EmitSimpleOMPExecutableDirective(*D);
+      return;
+    }
+  }
+
   switch (S->getStmtClass()) {
   case Stmt::NoStmtClass:
   case Stmt::CXXCatchStmtClass:
diff --git a/lib/CodeGen/CGStmtOpenMP.cpp b/lib/CodeGen/CGStmtOpenMP.cpp
index f9861735832bf..26817ac330ba8 100644
--- a/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/lib/CodeGen/CGStmtOpenMP.cpp
@@ -144,6 +144,71 @@ public:
   }
 };
 
+class OMPSimdLexicalScope : public CodeGenFunction::LexicalScope {
+  CodeGenFunction::OMPPrivateScope InlinedShareds;
+
+  static bool isCapturedVar(CodeGenFunction &CGF, const VarDecl *VD) {
+    return CGF.LambdaCaptureFields.lookup(VD) ||
+           (CGF.CapturedStmtInfo && CGF.CapturedStmtInfo->lookup(VD)) ||
+           (CGF.CurCodeDecl && isa<BlockDecl>(CGF.CurCodeDecl) &&
+            cast<BlockDecl>(CGF.CurCodeDecl)->capturesVariable(VD));
+  }
+
+public:
+  OMPSimdLexicalScope(CodeGenFunction &CGF, const OMPExecutableDirective &S)
+      : CodeGenFunction::LexicalScope(CGF, S.getSourceRange()),
+        InlinedShareds(CGF) {
+    for (const auto *C : S.clauses()) {
+      if (auto *CPI = OMPClauseWithPreInit::get(C)) {
+        if (auto *PreInit = cast_or_null<DeclStmt>(CPI->getPreInitStmt())) {
+          for (const auto *I : PreInit->decls()) {
+            if (!I->hasAttr<OMPCaptureNoInitAttr>())
+              CGF.EmitVarDecl(cast<VarDecl>(*I));
+            else {
+              CodeGenFunction::AutoVarEmission Emission =
+                  CGF.EmitAutoVarAlloca(cast<VarDecl>(*I));
+              CGF.EmitAutoVarCleanups(Emission);
+            }
+          }
+        }
+      } else if (const auto *UDP = dyn_cast<OMPUseDevicePtrClause>(C)) {
+        for (const Expr *E : UDP->varlists()) {
+          const Decl *D = cast<DeclRefExpr>(E)->getDecl();
+          if (const auto *OED = dyn_cast<OMPCapturedExprDecl>(D))
+            CGF.EmitVarDecl(*OED);
+        }
+      }
+    }
+    if (!isOpenMPSimdDirective(S.getDirectiveKind()))
+      CGF.EmitOMPPrivateClause(S, InlinedShareds);
+    if (const auto *TG = dyn_cast<OMPTaskgroupDirective>(&S)) {
+      if (const Expr *E = TG->getReductionRef())
+        CGF.EmitVarDecl(*cast<VarDecl>(cast<DeclRefExpr>(E)->getDecl()));
+    }
+    const auto *CS = cast_or_null<CapturedStmt>(S.getAssociatedStmt());
+    while (CS) {
+      for (auto &C : CS->captures()) {
+        if (C.capturesVariable() || C.capturesVariableByCopy()) {
+          auto *VD = C.getCapturedVar();
+          assert(VD == VD->getCanonicalDecl() &&
+                 "Canonical decl must be captured.");
+          DeclRefExpr DRE(const_cast<VarDecl *>(VD),
+                          isCapturedVar(CGF, VD) ||
+                              (CGF.CapturedStmtInfo &&
+                               InlinedShareds.isGlobalVarCaptured(VD)),
+                          VD->getType().getNonReferenceType(), VK_LValue,
+                          SourceLocation());
+          InlinedShareds.addPrivate(VD, [&CGF, &DRE]() -> Address {
+            return CGF.EmitLValue(&DRE).getAddress();
+          });
+        }
+      }
+      CS = dyn_cast<CapturedStmt>(CS->getCapturedStmt());
+    }
+    (void)InlinedShareds.Privatize();
+  }
+};
+
 } // namespace
 
 static void emitCommonOMPTargetDirective(CodeGenFunction &CGF,
@@ -863,7 +928,8 @@ bool CodeGenFunction::EmitOMPLastprivateClauseInit(
   llvm::DenseSet<const VarDecl *> AlreadyEmittedVars;
   for (const auto *C : D.getClausesOfKind<OMPLastprivateClause>()) {
     HasAtLeastOneLastprivate = true;
-    if (isOpenMPTaskLoopDirective(D.getDirectiveKind()))
+    if (isOpenMPTaskLoopDirective(D.getDirectiveKind()) &&
+        !getLangOpts().OpenMPSimd)
       break;
     auto IRef = C->varlist_begin();
     auto IDestRef = C->destination_exprs().begin();
@@ -1100,9 +1166,8 @@ void CodeGenFunction::EmitOMPReductionClauseFinal(
   if (HasAtLeastOneReduction) {
     bool WithNowait = D.getSingleClause<OMPNowaitClause>() ||
                       isOpenMPParallelDirective(D.getDirectiveKind()) ||
-                      D.getDirectiveKind() == OMPD_simd;
-    bool SimpleReduction = D.getDirectiveKind() == OMPD_simd ||
-                           D.getDirectiveKind() == OMPD_distribute_simd;
+                      ReductionKind == OMPD_simd;
+    bool SimpleReduction = ReductionKind == OMPD_simd;
     // Emit nowait reduction if nowait clause is present or directive is a
     // parallel directive (it always has implicit barrier).
     CGM.getOpenMPRuntime().emitReduction(
@@ -1570,6 +1635,14 @@ static void emitOMPLoopBodyWithStopPoint(CodeGenFunction &CGF,
   CGF.EmitStopPoint(&S);
 }
 
+/// Emit a helper variable and return corresponding lvalue.
+static LValue EmitOMPHelperVar(CodeGenFunction &CGF,
+                               const DeclRefExpr *Helper) {
+  auto VDecl = cast<VarDecl>(Helper->getDecl());
+  CGF.EmitVarDecl(*VDecl);
+  return CGF.EmitLValue(Helper);
+}
+
 static void emitOMPSimdRegion(CodeGenFunction &CGF, const OMPLoopDirective &S,
                               PrePostActionTy &Action) {
   Action.Enter(CGF);
@@ -1581,6 +1654,12 @@ static void emitOMPSimdRegion(CodeGenFunction &CGF, const OMPLoopDirective &S,
   //   <Final counter/linear vars updates>;
   // }
   //
+  if (isOpenMPDistributeDirective(S.getDirectiveKind()) ||
+      isOpenMPWorksharingDirective(S.getDirectiveKind()) ||
+      isOpenMPTaskLoopDirective(S.getDirectiveKind())) {
+    (void)EmitOMPHelperVar(CGF, cast<DeclRefExpr>(S.getLowerBoundVariable()));
+    (void)EmitOMPHelperVar(CGF, cast<DeclRefExpr>(S.getUpperBoundVariable()));
+  }
 
   // Emit: if (PreCond) - begin.
   // If the condition constant folds and can be elided, avoid emitting the
@@ -1933,14 +2012,6 @@ void CodeGenFunction::EmitOMPDistributeOuterLoop(
                    emitEmptyOrdered);
 }
 
-/// Emit a helper variable and return corresponding lvalue.
-static LValue EmitOMPHelperVar(CodeGenFunction &CGF,
-                               const DeclRefExpr *Helper) {
-  auto VDecl = cast<VarDecl>(Helper->getDecl());
-  CGF.EmitVarDecl(*VDecl);
-  return CGF.EmitLValue(Helper);
-}
-
 static std::pair<LValue, LValue>
 emitDistributeParallelForInnerBounds(CodeGenFunction &CGF,
                                      const OMPExecutableDirective &S) {
@@ -4721,3 +4792,35 @@ void CodeGenFunction::EmitOMPTargetUpdateDirective(
   OMPLexicalScope Scope(*this, S, /*AsInlined=*/true);
   CGM.getOpenMPRuntime().emitTargetDataStandAloneCall(*this, S, IfCond, Device);
 }
+
+void CodeGenFunction::EmitSimpleOMPExecutableDirective(
+    const OMPExecutableDirective &D) {
+  if (!D.hasAssociatedStmt() || !D.getAssociatedStmt())
+    return;
+  auto &&CodeGen = [&D](CodeGenFunction &CGF, PrePostActionTy &Action) {
+    if (isOpenMPSimdDirective(D.getDirectiveKind())) {
+      emitOMPSimdRegion(CGF, cast<OMPLoopDirective>(D), Action);
+    } else {
+      if (const auto *LD = dyn_cast<OMPLoopDirective>(&D)) {
+        for (const auto *E : LD->counters()) {
+          if (const auto *VD = dyn_cast<OMPCapturedExprDecl>(
+                  cast<DeclRefExpr>(E)->getDecl())) {
+            // Emit only those that were not explicitly referenced in clauses.
+            if (!CGF.LocalDeclMap.count(VD))
+              CGF.EmitVarDecl(*VD);
+          }
+        }
+      }
+      const auto *CS = cast<CapturedStmt>(D.getAssociatedStmt());
+      while (const auto *CCS = dyn_cast<CapturedStmt>(CS->getCapturedStmt()))
+        CS = CCS;
+      CGF.EmitStmt(CS->getCapturedStmt());
+    }
+  };
+  OMPSimdLexicalScope Scope(*this, D);
+  CGM.getOpenMPRuntime().emitInlinedDirective(
+      *this,
+      isOpenMPSimdDirective(D.getDirectiveKind()) ? OMPD_simd
+                                                  : D.getDirectiveKind(),
+      CodeGen);
+}
diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
index 9dbd7cc3fcbfb..664b51078424d 100644
--- a/lib/CodeGen/CodeGenFunction.cpp
+++ b/lib/CodeGen/CodeGenFunction.cpp
@@ -419,6 +419,9 @@ void CodeGenFunction::FinishFunction(SourceLocation EndLoc) {
   EmitIfUsed(*this, TerminateHandler);
   EmitIfUsed(*this, UnreachableBlock);
 
+  for (const auto &FuncletAndParent : TerminateFunclets)
+    EmitIfUsed(*this, FuncletAndParent.second);
+
   if (CGM.getCodeGenOpts().EmitDeclMetadata)
     EmitDeclMetadata();
 
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index dd4c2e43ef64b..3e89586be3a5f 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -34,6 +34,7 @@
 #include "clang/Frontend/CodeGenOptions.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/MapVector.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/IR/ValueHandle.h"
 #include "llvm/Support/Debug.h"
@@ -1420,6 +1421,9 @@ private:
   llvm::BasicBlock *TerminateHandler;
   llvm::BasicBlock *TrapBB;
 
+  /// Terminate funclets keyed by parent funclet pad.
+  llvm::MapVector<llvm::Value *, llvm::BasicBlock *> TerminateFunclets;
+
   /// True if we need emit the life-time markers.
   const bool ShouldEmitLifetimeMarkers;
 
@@ -1808,6 +1812,10 @@ public:
   /// getTerminateLandingPad - Return a landing pad that just calls terminate.
   llvm::BasicBlock *getTerminateLandingPad();
 
+  /// getTerminateLandingPad - Return a cleanup funclet that just calls
+  /// terminate.
+  llvm::BasicBlock *getTerminateFunclet();
+
   /// getTerminateHandler - Return a handler (not a landing pad, just
   /// a catch handler) that just calls terminate.  This is used when
   /// a terminate scope encloses a try.
@@ -2655,6 +2663,9 @@ public:
   llvm::Value *EmitSEHExceptionInfo();
   llvm::Value *EmitSEHAbnormalTermination();
 
+  /// Emit simple code for OpenMP directives in Simd-only mode.
+  void EmitSimpleOMPExecutableDirective(const OMPExecutableDirective &D);
+
   /// Scan the outlined statement for captures from the parent function. For
   /// each capture, mark the capture as escaped and emit a call to
   /// llvm.localrecover. Insert the localrecover result into the LocalDeclMap.
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 5bdf81aaf66ed..df33fc3e82001 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -208,7 +208,10 @@ void CodeGenModule::createOpenMPRuntime() {
     OpenMPRuntime.reset(new CGOpenMPRuntimeNVPTX(*this));
     break;
   default:
-    OpenMPRuntime.reset(new CGOpenMPRuntime(*this));
+    if (LangOpts.OpenMPSimd)
+      OpenMPRuntime.reset(new CGOpenMPSIMDRuntime(*this));
+    else
+      OpenMPRuntime.reset(new CGOpenMPRuntime(*this));
     break;
   }
 }
@@ -4515,6 +4518,9 @@ llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty,
 }
 
 void CodeGenModule::EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl *D) {
+  // Do not emit threadprivates in simd-only mode.
+  if (LangOpts.OpenMP && LangOpts.OpenMPSimd)
+    return;
   for (auto RefExpr : D->varlists()) {
     auto *VD = cast<VarDecl>(cast<DeclRefExpr>(RefExpr)->getDecl());
     bool PerformInit =
diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index 9ae33b80f8898..325b233ac5ec7 100644
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -62,6 +62,7 @@
 #include "llvm/Option/OptSpecifier.h"
 #include "llvm/Option/OptTable.h"
 #include "llvm/Option/Option.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
@@ -70,6 +71,7 @@
 #include "llvm/Support/Program.h"
 #include "llvm/Support/TargetRegistry.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/StringSaver.h"
 #include <map>
 #include <memory>
 #include <utility>
@@ -92,7 +94,8 @@ Driver::Driver(StringRef ClangExecutable, StringRef DefaultTargetTriple,
       CCPrintHeadersFilename(nullptr), CCLogDiagnosticsFilename(nullptr),
       CCCPrintBindings(false), CCPrintHeaders(false), CCLogDiagnostics(false),
       CCGenDiagnostics(false), DefaultTargetTriple(DefaultTargetTriple),
-      CCCGenericGCCName(""), CheckInputsExist(true), CCCUsePCH(true),
+      CCCGenericGCCName(""), Saver(Alloc),
+      CheckInputsExist(true), CCCUsePCH(true),
       GenReproducer(false), SuppressMissingInputWarning(false) {
 
   // Provide a sane fallback if no VFS is specified.
@@ -103,6 +106,13 @@ Driver::Driver(StringRef ClangExecutable, StringRef DefaultTargetTriple,
   Dir = llvm::sys::path::parent_path(ClangExecutable);
   InstalledDir = Dir; // Provide a sensible default installed dir.
 
+#if defined(CLANG_CONFIG_FILE_SYSTEM_DIR)
+  SystemConfigDir = CLANG_CONFIG_FILE_SYSTEM_DIR;
+#endif
+#if defined(CLANG_CONFIG_FILE_USER_DIR)
+  UserConfigDir = CLANG_CONFIG_FILE_USER_DIR;
+#endif
+
   // Compute the path to the resource directory.
   StringRef ClangResourceDir(CLANG_RESOURCE_DIR);
   SmallString<128> P(Dir);
@@ -600,6 +610,216 @@ void Driver::CreateOffloadingDeviceToolChains(Compilation &C,
   //
 }
 
+/// Looks the given directories for the specified file.
+///
+/// \param[out] FilePath File path, if the file was found.
+/// \param[in]  Dirs Directories used for the search.
+/// \param[in]  FileName Name of the file to search for.
+/// \return True if file was found.
+///
+/// Looks for file specified by FileName sequentially in directories specified
+/// by Dirs.
+///
+static bool searchForFile(SmallVectorImpl<char> &FilePath,
+                          ArrayRef<std::string> Dirs,
+                          StringRef FileName) {
+  SmallString<128> WPath;
+  for (const StringRef &Dir : Dirs) {
+    if (Dir.empty())
+      continue;
+    WPath.clear();
+    llvm::sys::path::append(WPath, Dir, FileName);
+    llvm::sys::path::native(WPath);
+    if (llvm::sys::fs::is_regular_file(WPath)) {
+      FilePath = std::move(WPath);
+      return true;
+    }
+  }
+  return false;
+}
+
+bool Driver::readConfigFile(StringRef FileName) {
+  // Try reading the given file.
+  SmallVector<const char *, 32> NewCfgArgs;
+  if (!llvm::cl::readConfigFile(FileName, Saver, NewCfgArgs)) {
+    Diag(diag::err_drv_cannot_read_config_file) << FileName;
+    return true;
+  }
+
+  // Read options from config file.
+  llvm::SmallString<128> CfgFileName(FileName);
+  llvm::sys::path::native(CfgFileName);
+  ConfigFile = CfgFileName.str();
+  bool ContainErrors;
+  CfgOptions = llvm::make_unique<InputArgList>(
+      ParseArgStrings(NewCfgArgs, ContainErrors));
+  if (ContainErrors) {
+    CfgOptions.reset();
+    return true;
+  }
+
+  if (CfgOptions->hasArg(options::OPT_config)) {
+    CfgOptions.reset();
+    Diag(diag::err_drv_nested_config_file);
+    return true;
+  }
+
+  // Claim all arguments that come from a configuration file so that the driver
+  // does not warn on any that is unused.
+  for (Arg *A : *CfgOptions)
+    A->claim();
+  return false;
+}
+
+bool Driver::loadConfigFile() {
+  std::string CfgFileName;
+  bool FileSpecifiedExplicitly = false;
+
+  // Process options that change search path for config files.
+  if (CLOptions) {
+    if (CLOptions->hasArg(options::OPT_config_system_dir_EQ)) {
+      SmallString<128> CfgDir;
+      CfgDir.append(
+          CLOptions->getLastArgValue(options::OPT_config_system_dir_EQ));
+      if (!CfgDir.empty()) {
+        if (llvm::sys::fs::make_absolute(CfgDir).value() != 0)
+          SystemConfigDir.clear();
+        else
+          SystemConfigDir = std::string(CfgDir.begin(), CfgDir.end());
+      }
+    }
+    if (CLOptions->hasArg(options::OPT_config_user_dir_EQ)) {
+      SmallString<128> CfgDir;
+      CfgDir.append(
+          CLOptions->getLastArgValue(options::OPT_config_user_dir_EQ));
+      if (!CfgDir.empty()) {
+        if (llvm::sys::fs::make_absolute(CfgDir).value() != 0)
+          UserConfigDir.clear();
+        else
+          UserConfigDir = std::string(CfgDir.begin(), CfgDir.end());
+      }
+    }
+  }
+
+  // First try to find config file specified in command line.
+  if (CLOptions) {
+    std::vector<std::string> ConfigFiles =
+        CLOptions->getAllArgValues(options::OPT_config);
+    if (ConfigFiles.size() > 1) {
+      Diag(diag::err_drv_duplicate_config);
+      return true;
+    }
+
+    if (!ConfigFiles.empty()) {
+      CfgFileName = ConfigFiles.front();
+      assert(!CfgFileName.empty());
+
+      // If argument contains directory separator, treat it as a path to
+      // configuration file.
+      if (llvm::sys::path::has_parent_path(CfgFileName)) {
+        SmallString<128> CfgFilePath;
+        if (llvm::sys::path::is_relative(CfgFileName))
+          llvm::sys::fs::current_path(CfgFilePath);
+        llvm::sys::path::append(CfgFilePath, CfgFileName);
+        if (!llvm::sys::fs::is_regular_file(CfgFilePath)) {
+          Diag(diag::err_drv_config_file_not_exist) << CfgFilePath;
+          return true;
+        }
+        return readConfigFile(CfgFilePath);
+      }
+
+      FileSpecifiedExplicitly = true;
+    }
+  }
+
+  // If config file is not specified explicitly, try to deduce configuration
+  // from executable name. For instance, an executable 'armv7l-clang' will
+  // search for config file 'armv7l-clang.cfg'.
+  if (CfgFileName.empty() && !ClangNameParts.TargetPrefix.empty())
+    CfgFileName = ClangNameParts.TargetPrefix + '-' + ClangNameParts.ModeSuffix;
+
+  if (CfgFileName.empty())
+    return false;
+
+  // Determine architecture part of the file name, if it is present.
+  StringRef CfgFileArch = CfgFileName;
+  size_t ArchPrefixLen = CfgFileArch.find('-');
+  if (ArchPrefixLen == StringRef::npos)
+    ArchPrefixLen = CfgFileArch.size();
+  llvm::Triple CfgTriple;
+  CfgFileArch = CfgFileArch.take_front(ArchPrefixLen);
+  CfgTriple = llvm::Triple(llvm::Triple::normalize(CfgFileArch));
+  if (CfgTriple.getArch() == llvm::Triple::ArchType::UnknownArch)
+    ArchPrefixLen = 0;
+
+  if (!StringRef(CfgFileName).endswith(".cfg"))
+    CfgFileName += ".cfg";
+
+  // If config file starts with architecture name and command line options
+  // redefine architecture (with options like -m32 -LE etc), try finding new
+  // config file with that architecture.
+  SmallString<128> FixedConfigFile;
+  size_t FixedArchPrefixLen = 0;
+  if (ArchPrefixLen) {
+    // Get architecture name from config file name like 'i386.cfg' or
+    // 'armv7l-clang.cfg'.
+    // Check if command line options changes effective triple.
+    llvm::Triple EffectiveTriple = computeTargetTriple(*this,
+                                             CfgTriple.getTriple(), *CLOptions);
+    if (CfgTriple.getArch() != EffectiveTriple.getArch()) {
+      FixedConfigFile = EffectiveTriple.getArchName();
+      FixedArchPrefixLen = FixedConfigFile.size();
+      // Append the rest of original file name so that file name transforms
+      // like: i386-clang.cfg -> x86_64-clang.cfg.
+      if (ArchPrefixLen < CfgFileName.size())
+        FixedConfigFile += CfgFileName.substr(ArchPrefixLen);
+    }
+  }
+
+  // Prepare list of directories where config file is searched for.
+  SmallVector<std::string, 3> CfgFileSearchDirs;
+  CfgFileSearchDirs.push_back(UserConfigDir);
+  CfgFileSearchDirs.push_back(SystemConfigDir);
+  CfgFileSearchDirs.push_back(Dir);
+
+  // Try to find config file. First try file with corrected architecture.
+  llvm::SmallString<128> CfgFilePath;
+  if (!FixedConfigFile.empty()) {
+    if (searchForFile(CfgFilePath, CfgFileSearchDirs, FixedConfigFile))
+      return readConfigFile(CfgFilePath);
+    // If 'x86_64-clang.cfg' was not found, try 'x86_64.cfg'.
+    FixedConfigFile.resize(FixedArchPrefixLen);
+    FixedConfigFile.append(".cfg");
+    if (searchForFile(CfgFilePath, CfgFileSearchDirs, FixedConfigFile))
+      return readConfigFile(CfgFilePath);
+  }
+
+  // Then try original file name.
+  if (searchForFile(CfgFilePath, CfgFileSearchDirs, CfgFileName))
+    return readConfigFile(CfgFilePath);
+
+  // Finally try removing driver mode part: 'x86_64-clang.cfg' -> 'x86_64.cfg'.
+  if (!ClangNameParts.ModeSuffix.empty() &&
+      !ClangNameParts.TargetPrefix.empty()) {
+    CfgFileName.assign(ClangNameParts.TargetPrefix);
+    CfgFileName.append(".cfg");
+    if (searchForFile(CfgFilePath, CfgFileSearchDirs, CfgFileName))
+      return readConfigFile(CfgFilePath);
+  }
+
+  // Report error but only if config file was specified explicitly, by option
+  // --config. If it was deduced from executable name, it is not an error.
+  if (FileSpecifiedExplicitly) {
+    Diag(diag::err_drv_config_file_not_found) << CfgFileName;
+    for (const std::string &SearchDir : CfgFileSearchDirs)
+      if (!SearchDir.empty())
+        Diag(diag::note_drv_config_file_searched_in) << SearchDir;
+    return true;
+  }
+
+  return false;
+}
+
 Compilation *Driver::BuildCompilation(ArrayRef<const char *> ArgList) {
   llvm::PrettyStackTraceString CrashInfo("Compilation construction");
 
@@ -623,12 +843,35 @@ Compilation *Driver::BuildCompilation(ArrayRef<const char *> ArgList) {
 
   // FIXME: What are we going to do with -V and -b?
 
+  // Arguments specified in command line.
+  bool ContainsError;
+  CLOptions = llvm::make_unique<InputArgList>(
+      ParseArgStrings(ArgList.slice(1), ContainsError));
+
+  // Try parsing configuration file.
+  if (!ContainsError)
+    ContainsError = loadConfigFile();
+  bool HasConfigFile = !ContainsError && (CfgOptions.get() != nullptr);
+
+  // All arguments, from both config file and command line.
+  InputArgList Args = std::move(HasConfigFile ? std::move(*CfgOptions)
+                                              : std::move(*CLOptions));
+  if (HasConfigFile)
+    for (auto *Opt : *CLOptions) {
+      const Arg *BaseArg = &Opt->getBaseArg();
+      if (BaseArg == Opt)
+        BaseArg = nullptr;
+      Arg *Copy = new llvm::opt::Arg(Opt->getOption(), Opt->getSpelling(),
+                                     Args.size(), BaseArg);
+      Copy->getValues() = Opt->getValues();
+      if (Opt->isClaimed())
+        Copy->claim();
+      Args.append(Copy);
+    }
+
   // FIXME: This stuff needs to go into the Compilation, not the driver.
   bool CCCPrintPhases;
 
-  bool ContainsError;
-  InputArgList Args = ParseArgStrings(ArgList.slice(1), ContainsError);
-
   // Silence driver warnings if requested
   Diags.setIgnoreAllWarnings(Args.hasArg(options::OPT_w));
 
@@ -1144,6 +1387,10 @@ void Driver::PrintVersion(const Compilation &C, raw_ostream &OS) const {
 
   // Print out the install directory.
   OS << "InstalledDir: " << InstalledDir << '\n';
+
+  // If configuration file was used, print its path.
+  if (!ConfigFile.empty())
+    OS << "Configuration file: " << ConfigFile << '\n';
 }
 
 /// PrintDiagnosticCategories - Implement the --print-diagnostic-categories
@@ -1250,6 +1497,15 @@ bool Driver::HandleImmediateArgs(const Compilation &C) {
     SuppressMissingInputWarning = true;
   }
 
+  if (C.getArgs().hasArg(options::OPT_v)) {
+    if (!SystemConfigDir.empty())
+      llvm::errs() << "System configuration file directory: "
+                   << SystemConfigDir << "\n";
+    if (!UserConfigDir.empty())
+      llvm::errs() << "User configuration file directory: "
+                   << UserConfigDir << "\n";
+  }
+
   const ToolChain &TC = C.getDefaultToolChain();
 
   if (C.getArgs().hasArg(options::OPT_v))
diff --git a/lib/Driver/ToolChains/Clang.cpp b/lib/Driver/ToolChains/Clang.cpp
index 8b895c4514c45..c445669a5ad42 100644
--- a/lib/Driver/ToolChains/Clang.cpp
+++ b/lib/Driver/ToolChains/Clang.cpp
@@ -3901,6 +3901,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
       // semantic analysis, etc.
       break;
     }
+  } else {
+    Args.AddLastArg(CmdArgs, options::OPT_fopenmp_simd,
+                    options::OPT_fno_openmp_simd);
+    Args.AddAllArgs(CmdArgs, options::OPT_fopenmp_version_EQ);
   }
 
   const SanitizerArgs &Sanitize = getToolChain().getSanitizerArgs();
diff --git a/lib/Driver/ToolChains/Darwin.cpp b/lib/Driver/ToolChains/Darwin.cpp
index 2250e82d9dbfe..802b89b070025 100644
--- a/lib/Driver/ToolChains/Darwin.cpp
+++ b/lib/Driver/ToolChains/Darwin.cpp
@@ -1192,6 +1192,13 @@ struct DarwinPlatform {
     return OSVersion;
   }
 
+  void setOSVersion(StringRef S) {
+    assert(Kind == TargetArg && "Unexpected kind!");
+    OSVersion = S;
+  }
+
+  bool hasOSVersion() const { return HasOSVersion; }
+
   /// Returns true if the target OS was explicitly specified.
   bool isExplicitlySpecified() const { return Kind <= DeploymentTargetEnv; }
 
@@ -1235,17 +1242,21 @@ struct DarwinPlatform {
     llvm_unreachable("Unsupported Darwin Source Kind");
   }
 
-  static DarwinPlatform createFromTarget(llvm::Triple::OSType OS,
-                                         StringRef OSVersion, Arg *A,
-                                         llvm::Triple::EnvironmentType Env) {
-    DarwinPlatform Result(TargetArg, getPlatformFromOS(OS), OSVersion, A);
-    switch (Env) {
+  static DarwinPlatform createFromTarget(const llvm::Triple &TT,
+                                         StringRef OSVersion, Arg *A) {
+    DarwinPlatform Result(TargetArg, getPlatformFromOS(TT.getOS()), OSVersion,
+                          A);
+    switch (TT.getEnvironment()) {
     case llvm::Triple::Simulator:
       Result.Environment = DarwinEnvironmentKind::Simulator;
       break;
     default:
       break;
     }
+    unsigned Major, Minor, Micro;
+    TT.getOSVersion(Major, Minor, Micro);
+    if (Major == 0)
+      Result.HasOSVersion = false;
     return Result;
   }
   static DarwinPlatform createOSVersionArg(DarwinPlatformKind Platform,
@@ -1295,6 +1306,7 @@ private:
   DarwinPlatformKind Platform;
   DarwinEnvironmentKind Environment = DarwinEnvironmentKind::NativeEnvironment;
   std::string OSVersion;
+  bool HasOSVersion = true;
   Arg *Argument;
   StringRef EnvVarName;
 };
@@ -1489,9 +1501,8 @@ Optional<DarwinPlatform> getDeploymentTargetFromTargetArg(
       Triple.getOS() == llvm::Triple::UnknownOS)
     return None;
   std::string OSVersion = getOSVersion(Triple.getOS(), Triple, TheDriver);
-  return DarwinPlatform::createFromTarget(Triple.getOS(), OSVersion,
-                                          Args.getLastArg(options::OPT_target),
-                                          Triple.getEnvironment());
+  return DarwinPlatform::createFromTarget(Triple, OSVersion,
+                                          Args.getLastArg(options::OPT_target));
 }
 
 } // namespace
@@ -1537,12 +1548,20 @@ void Darwin::AddDeploymentTarget(DerivedArgList &Args) const {
            (VersionTuple(TargetMajor, TargetMinor, TargetMicro) !=
                 VersionTuple(ArgMajor, ArgMinor, ArgMicro) ||
             TargetExtra != ArgExtra))) {
-        // Warn about -m<os>-version-min that doesn't match the OS version
-        // that's specified in the target.
-        std::string OSVersionArg = OSVersionArgTarget->getAsString(Args, Opts);
-        std::string TargetArg = OSTarget->getAsString(Args, Opts);
-        getDriver().Diag(clang::diag::warn_drv_overriding_flag_option)
-            << OSVersionArg << TargetArg;
+        // Select the OS version from the -m<os>-version-min argument when
+        // the -target does not include an OS version.
+        if (OSTarget->getPlatform() == OSVersionArgTarget->getPlatform() &&
+            !OSTarget->hasOSVersion()) {
+          OSTarget->setOSVersion(OSVersionArgTarget->getOSVersion());
+        } else {
+          // Warn about -m<os>-version-min that doesn't match the OS version
+          // that's specified in the target.
+          std::string OSVersionArg =
+              OSVersionArgTarget->getAsString(Args, Opts);
+          std::string TargetArg = OSTarget->getAsString(Args, Opts);
+          getDriver().Diag(clang::diag::warn_drv_overriding_flag_option)
+              << OSVersionArg << TargetArg;
+        }
       }
     }
   } else {
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 2e8a737de4e42..6ce719aac6733 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -2407,16 +2407,22 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
 
   // Check if -fopenmp is specified.
   Opts.OpenMP = Args.hasArg(options::OPT_fopenmp) ? 1 : 0;
+  // Check if -fopenmp-simd is specified.
+  Opts.OpenMPSimd = !Opts.OpenMP && Args.hasFlag(options::OPT_fopenmp_simd,
+                                                 options::OPT_fno_openmp_simd,
+                                                 /*Default=*/false);
   Opts.OpenMPUseTLS =
       Opts.OpenMP && !Args.hasArg(options::OPT_fnoopenmp_use_tls);
   Opts.OpenMPIsDevice =
       Opts.OpenMP && Args.hasArg(options::OPT_fopenmp_is_device);
 
-  if (Opts.OpenMP) {
-    int Version =
-        getLastArgIntValue(Args, OPT_fopenmp_version_EQ, Opts.OpenMP, Diags);
-    if (Version != 0)
+  if (Opts.OpenMP || Opts.OpenMPSimd) {
+    if (int Version =
+            getLastArgIntValue(Args, OPT_fopenmp_version_EQ,
+                               Opts.OpenMPSimd ? 45 : Opts.OpenMP, Diags))
       Opts.OpenMP = Version;
+    else if (Opts.OpenMPSimd)
+      Opts.OpenMP = 45;
     // Provide diagnostic when a given target is not expected to be an OpenMP
     // device or host.
     if (!Opts.OpenMPIsDevice) {
diff --git a/lib/Frontend/InitPreprocessor.cpp b/lib/Frontend/InitPreprocessor.cpp
index d39890494323d..639050f7c64b8 100644
--- a/lib/Frontend/InitPreprocessor.cpp
+++ b/lib/Frontend/InitPreprocessor.cpp
@@ -1021,8 +1021,8 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
     Builder.defineMacro("_OPENMP", "201511");
     break;
   default:
-    // Default version is OpenMP 3.1
-    Builder.defineMacro("_OPENMP", "201107");
+    // Default version is OpenMP 3.1, in Simd only mode - 4.5
+    Builder.defineMacro("_OPENMP", LangOpts.OpenMPSimd ? "201511" : "201107");
     break;
   }
 
diff --git a/lib/Headers/emmintrin.h b/lib/Headers/emmintrin.h
index 3372508a7f818..b332eeec205ae 100644
--- a/lib/Headers/emmintrin.h
+++ b/lib/Headers/emmintrin.h
@@ -217,8 +217,8 @@ _mm_div_pd(__m128d __a, __m128d __b)
 
 /// \brief Calculates the square root of the lower double-precision value of
 ///    the second operand and returns it in the lower 64 bits of the result.
-///    The upper 64 bits of the result are copied from the upper double-
-///    precision value of the first operand.
+///    The upper 64 bits of the result are copied from the upper
+///    double-precision value of the first operand.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -260,8 +260,8 @@ _mm_sqrt_pd(__m128d __a)
 
 /// \brief Compares lower 64-bit double-precision values of both operands, and
 ///    returns the lesser of the pair of values in the lower 64-bits of the
-///    result. The upper 64 bits of the result are copied from the upper double-
-///    precision value of the first operand.
+///    result. The upper 64 bits of the result are copied from the upper
+///    double-precision value of the first operand.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -304,8 +304,8 @@ _mm_min_pd(__m128d __a, __m128d __b)
 
 /// \brief Compares lower 64-bit double-precision values of both operands, and
 ///    returns the greater of the pair of values in the lower 64-bits of the
-///    result. The upper 64 bits of the result are copied from the upper double-
-///    precision value of the first operand.
+///    result. The upper 64 bits of the result are copied from the upper
+///    double-precision value of the first operand.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -983,8 +983,10 @@ _mm_cmpnge_sd(__m128d __a, __m128d __b)
 }
 
 /// \brief Compares the lower double-precision floating-point values in each of
-///    the two 128-bit floating-point vectors of [2 x double] for equality. The
-///    comparison yields 0 for false, 1 for true.
+///    the two 128-bit floating-point vectors of [2 x double] for equality.
+///
+///    The comparison yields 0 for false, 1 for true. If either of the two
+///    lower double-precision values is NaN, 0 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -996,7 +998,8 @@ _mm_cmpnge_sd(__m128d __a, __m128d __b)
 /// \param __b
 ///    A 128-bit vector of [2 x double]. The lower double-precision value is
 ///    compared to the lower double-precision value of \a __a.
-/// \returns An integer containing the comparison results.
+/// \returns An integer containing the comparison results. If either of the two
+///    lower double-precision values is NaN, 0 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_comieq_sd(__m128d __a, __m128d __b)
 {
@@ -1008,7 +1011,8 @@ _mm_comieq_sd(__m128d __a, __m128d __b)
 ///    the value in the first parameter is less than the corresponding value in
 ///    the second parameter.
 ///
-///    The comparison yields 0 for false, 1 for true.
+///    The comparison yields 0 for false, 1 for true. If either of the two
+///    lower double-precision values is NaN, 0 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1020,7 +1024,8 @@ _mm_comieq_sd(__m128d __a, __m128d __b)
 /// \param __b
 ///    A 128-bit vector of [2 x double]. The lower double-precision value is
 ///    compared to the lower double-precision value of \a __a.
-/// \returns An integer containing the comparison results.
+/// \returns An integer containing the comparison results. If either of the two
+///     lower double-precision values is NaN, 0 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_comilt_sd(__m128d __a, __m128d __b)
 {
@@ -1032,7 +1037,8 @@ _mm_comilt_sd(__m128d __a, __m128d __b)
 ///    the value in the first parameter is less than or equal to the
 ///    corresponding value in the second parameter.
 ///
-///    The comparison yields 0 for false, 1 for true.
+///    The comparison yields 0 for false, 1 for true. If either of the two
+///    lower double-precision values is NaN, 0 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1044,7 +1050,8 @@ _mm_comilt_sd(__m128d __a, __m128d __b)
 /// \param __b
 ///     A 128-bit vector of [2 x double]. The lower double-precision value is
 ///     compared to the lower double-precision value of \a __a.
-/// \returns An integer containing the comparison results.
+/// \returns An integer containing the comparison results. If either of the two
+///     lower double-precision values is NaN, 0 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_comile_sd(__m128d __a, __m128d __b)
 {
@@ -1056,7 +1063,8 @@ _mm_comile_sd(__m128d __a, __m128d __b)
 ///    the value in the first parameter is greater than the corresponding value
 ///    in the second parameter.
 ///
-///    The comparison yields 0 for false, 1 for true.
+///    The comparison yields 0 for false, 1 for true. If either of the two
+///    lower double-precision values is NaN, 0 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1068,7 +1076,8 @@ _mm_comile_sd(__m128d __a, __m128d __b)
 /// \param __b
 ///    A 128-bit vector of [2 x double]. The lower double-precision value is
 ///    compared to the lower double-precision value of \a __a.
-/// \returns An integer containing the comparison results.
+/// \returns An integer containing the comparison results. If either of the two
+///     lower double-precision values is NaN, 0 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_comigt_sd(__m128d __a, __m128d __b)
 {
@@ -1080,7 +1089,8 @@ _mm_comigt_sd(__m128d __a, __m128d __b)
 ///    the value in the first parameter is greater than or equal to the
 ///    corresponding value in the second parameter.
 ///
-///    The comparison yields 0 for false, 1 for true.
+///    The comparison yields 0 for false, 1 for true. If either of the two
+///    lower double-precision values is NaN, 0 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1092,7 +1102,8 @@ _mm_comigt_sd(__m128d __a, __m128d __b)
 /// \param __b
 ///    A 128-bit vector of [2 x double]. The lower double-precision value is
 ///    compared to the lower double-precision value of \a __a.
-/// \returns An integer containing the comparison results.
+/// \returns An integer containing the comparison results. If either of the two
+///    lower double-precision values is NaN, 0 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_comige_sd(__m128d __a, __m128d __b)
 {
@@ -1104,7 +1115,8 @@ _mm_comige_sd(__m128d __a, __m128d __b)
 ///    the value in the first parameter is unequal to the corresponding value in
 ///    the second parameter.
 ///
-///    The comparison yields 0 for false, 1 for true.
+///    The comparison yields 0 for false, 1 for true. If either of the two
+///    lower double-precision values is NaN, 1 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1116,7 +1128,8 @@ _mm_comige_sd(__m128d __a, __m128d __b)
 /// \param __b
 ///    A 128-bit vector of [2 x double]. The lower double-precision value is
 ///    compared to the lower double-precision value of \a __a.
-/// \returns An integer containing the comparison results.
+/// \returns An integer containing the comparison results. If either of the two
+///     lower double-precision values is NaN, 1 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_comineq_sd(__m128d __a, __m128d __b)
 {
@@ -1127,7 +1140,7 @@ _mm_comineq_sd(__m128d __a, __m128d __b)
 ///    the two 128-bit floating-point vectors of [2 x double] for equality. The
 ///    comparison yields 0 for false, 1 for true.
 ///
-///    If either of the two lower double-precision values is NaN, 1 is returned.
+///    If either of the two lower double-precision values is NaN, 0 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1140,7 +1153,7 @@ _mm_comineq_sd(__m128d __a, __m128d __b)
 ///    A 128-bit vector of [2 x double]. The lower double-precision value is
 ///    compared to the lower double-precision value of \a __a.
 /// \returns An integer containing the comparison results. If either of the two
-///    lower double-precision values is NaN, 1 is returned.
+///    lower double-precision values is NaN, 0 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_ucomieq_sd(__m128d __a, __m128d __b)
 {
@@ -1153,7 +1166,7 @@ _mm_ucomieq_sd(__m128d __a, __m128d __b)
 ///    the second parameter.
 ///
 ///    The comparison yields 0 for false, 1 for true. If either of the two lower
-///    double-precision values is NaN, 1 is returned.
+///    double-precision values is NaN, 0 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1166,7 +1179,7 @@ _mm_ucomieq_sd(__m128d __a, __m128d __b)
 ///    A 128-bit vector of [2 x double]. The lower double-precision value is
 ///    compared to the lower double-precision value of \a __a.
 /// \returns An integer containing the comparison results. If either of the two
-///    lower double-precision values is NaN, 1 is returned.
+///    lower double-precision values is NaN, 0 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_ucomilt_sd(__m128d __a, __m128d __b)
 {
@@ -1179,7 +1192,7 @@ _mm_ucomilt_sd(__m128d __a, __m128d __b)
 ///    corresponding value in the second parameter.
 ///
 ///    The comparison yields 0 for false, 1 for true. If either of the two lower
-///    double-precision values is NaN, 1 is returned.
+///    double-precision values is NaN, 0 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1192,7 +1205,7 @@ _mm_ucomilt_sd(__m128d __a, __m128d __b)
 ///     A 128-bit vector of [2 x double]. The lower double-precision value is
 ///     compared to the lower double-precision value of \a __a.
 /// \returns An integer containing the comparison results. If either of the two
-///     lower double-precision values is NaN, 1 is returned.
+///     lower double-precision values is NaN, 0 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_ucomile_sd(__m128d __a, __m128d __b)
 {
@@ -1257,7 +1270,7 @@ _mm_ucomige_sd(__m128d __a, __m128d __b)
 ///    the second parameter.
 ///
 ///    The comparison yields 0 for false, 1 for true. If either of the two lower
-///    double-precision values is NaN, 0 is returned.
+///    double-precision values is NaN, 1 is returned.
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -1270,7 +1283,7 @@ _mm_ucomige_sd(__m128d __a, __m128d __b)
 ///    A 128-bit vector of [2 x double]. The lower double-precision value is
 ///    compared to the lower double-precision value of \a __a.
 /// \returns An integer containing the comparison result. If either of the two
-///    lower double-precision values is NaN, 0 is returned.
+///    lower double-precision values is NaN, 1 is returned.
 static __inline__ int __DEFAULT_FN_ATTRS
 _mm_ucomineq_sd(__m128d __a, __m128d __b)
 {
@@ -1935,14 +1948,15 @@ _mm_store_pd(double *__dp, __m128d __a)
 ///
 /// \headerfile <x86intrin.h>
 ///
-/// This intrinsic corresponds to the <c>VMOVDDUP + VMOVAPD / MOVLHPS + MOVAPS </c> instruction.
+/// This intrinsic corresponds to the
+///   <c> VMOVDDUP + VMOVAPD / MOVLHPS + MOVAPS </c> instruction.
 ///
 /// \param __dp
 ///    A pointer to a memory location that can store two double-precision
 ///    values.
 /// \param __a
 ///    A 128-bit vector of [2 x double] whose lower 64 bits are copied to each
-///    of the values in \a dp.
+///    of the values in \a __dp.
 static __inline__ void __DEFAULT_FN_ATTRS
 _mm_store1_pd(double *__dp, __m128d __a)
 {
@@ -1950,18 +1964,20 @@ _mm_store1_pd(double *__dp, __m128d __a)
   _mm_store_pd(__dp, __a);
 }
 
-/// \brief Stores a 128-bit vector of [2 x double] into an aligned memory
-///    location.
+/// \brief Moves the lower 64 bits of a 128-bit vector of [2 x double] twice to
+///    the upper and lower 64 bits of a memory location.
 ///
 /// \headerfile <x86intrin.h>
 ///
-/// This intrinsic corresponds to the <c> VMOVAPD / MOVAPD </c> instruction.
+/// This intrinsic corresponds to the
+///   <c> VMOVDDUP + VMOVAPD / MOVLHPS + MOVAPS </c> instruction.
 ///
 /// \param __dp
-///    A pointer to a 128-bit memory location. The address of the memory
-///    location has to be 16-byte aligned.
+///    A pointer to a memory location that can store two double-precision
+///    values.
 /// \param __a
-///    A 128-bit vector of [2 x double] containing the values to be stored.
+///    A 128-bit vector of [2 x double] whose lower 64 bits are copied to each
+///    of the values in \a __dp.
 static __inline__ void __DEFAULT_FN_ATTRS
 _mm_store_pd1(double *__dp, __m128d __a)
 {
@@ -3846,8 +3862,7 @@ _mm_set1_epi8(char __b)
 ///
 /// \headerfile <x86intrin.h>
 ///
-/// This intrinsic corresponds to the <c> VPUNPCKLQDQ / PUNPCKLQDQ </c>
-///   instruction.
+/// This intrinsic does not correspond to a specific instruction.
 ///
 /// \param __q0
 ///    A 64-bit integral value used to initialize the lower 64 bits of the
@@ -4018,7 +4033,7 @@ _mm_storeu_si128(__m128i *__p, __m128i __b)
 ///    specified unaligned memory location. When a mask bit is 1, the
 ///    corresponding byte is written, otherwise it is not written.
 ///
-///    To minimize caching, the date is flagged as non-temporal (unlikely to be
+///    To minimize caching, the data is flagged as non-temporal (unlikely to be
 ///    used again soon). Exception and trap behavior for elements not selected
 ///    for storage to memory are implementation dependent.
 ///
@@ -4532,8 +4547,8 @@ _mm_unpackhi_epi32(__m128i __a, __m128i __b)
   return (__m128i)__builtin_shufflevector((__v4si)__a, (__v4si)__b, 2, 4+2, 3, 4+3);
 }
 
-/// \brief Unpacks the high-order (odd-indexed) values from two 128-bit vectors
-///    of [2 x i64] and interleaves them into a 128-bit vector of [2 x i64].
+/// \brief Unpacks the high-order 64-bit elements from two 128-bit vectors of
+///    [2 x i64] and interleaves them into a 128-bit vector of [2 x i64].
 ///
 /// \headerfile <x86intrin.h>
 ///
@@ -4665,7 +4680,7 @@ _mm_unpacklo_epi64(__m128i __a, __m128i __b)
 ///
 /// \headerfile <x86intrin.h>
 ///
-/// This intrinsic has no corresponding instruction.
+/// This intrinsic corresponds to the <c> MOVDQ2Q </c> instruction.
 ///
 /// \param __a
 ///    A 128-bit integer vector operand. The lower 64 bits are moved to the
@@ -4682,7 +4697,7 @@ _mm_movepi64_pi64(__m128i __a)
 ///
 /// \headerfile <x86intrin.h>
 ///
-/// This intrinsic corresponds to the <c> VMOVQ / MOVQ / MOVD </c> instruction.
+/// This intrinsic corresponds to the <c> MOVD+VMOVQ </c> instruction.
 ///
 /// \param __a
 ///    A 64-bit value.
@@ -4712,8 +4727,8 @@ _mm_move_epi64(__m128i __a)
   return __builtin_shufflevector((__v2di)__a, (__m128i){ 0 }, 0, 2);
 }
 
-/// \brief Unpacks the high-order (odd-indexed) values from two 128-bit vectors
-///    of [2 x double] and interleaves them into a 128-bit vector of [2 x
+/// \brief Unpacks the high-order 64-bit elements from two 128-bit vectors of
+///    [2 x double] and interleaves them into a 128-bit vector of [2 x
 ///    double].
 ///
 /// \headerfile <x86intrin.h>
@@ -4733,7 +4748,7 @@ _mm_unpackhi_pd(__m128d __a, __m128d __b)
   return __builtin_shufflevector((__v2df)__a, (__v2df)__b, 1, 2+1);
 }
 
-/// \brief Unpacks the low-order (even-indexed) values from two 128-bit vectors
+/// \brief Unpacks the low-order 64-bit elements from two 128-bit vectors
 ///    of [2 x double] and interleaves them into a 128-bit vector of [2 x
 ///    double].
 ///
@@ -4792,9 +4807,9 @@ _mm_movemask_pd(__m128d __a)
 ///    A 128-bit vector of [2 x double].
 /// \param i
 ///    An 8-bit immediate value. The least significant two bits specify which
-///    elements to copy from a and b: \n
-///    Bit[0] = 0: lower element of a copied to lower element of result. \n
-///    Bit[0] = 1: upper element of a copied to lower element of result. \n
+///    elements to copy from \a a and \a b: \n
+///    Bit[0] = 0: lower element of \a a copied to lower element of result. \n
+///    Bit[0] = 1: upper element of \a a copied to lower element of result. \n
 ///    Bit[1] = 0: lower element of \a b copied to upper element of result. \n
 ///    Bit[1] = 1: upper element of \a b copied to upper element of result. \n
 /// \returns A 128-bit vector of [2 x double] containing the shuffled values.
diff --git a/lib/Headers/pmmintrin.h b/lib/Headers/pmmintrin.h
index 559ece2e3974f..7ec08a1bcbb37 100644
--- a/lib/Headers/pmmintrin.h
+++ b/lib/Headers/pmmintrin.h
@@ -115,8 +115,8 @@ _mm_hsub_ps(__m128 __a, __m128 __b)
   return __builtin_ia32_hsubps((__v4sf)__a, (__v4sf)__b);
 }
 
-/// \brief Moves and duplicates high-order (odd-indexed) values from a 128-bit
-///    vector of [4 x float] to float values stored in a 128-bit vector of
+/// \brief Moves and duplicates odd-indexed values from a 128-bit vector
+///    of [4 x float] to float values stored in a 128-bit vector of
 ///    [4 x float].
 ///
 /// \headerfile <x86intrin.h>
@@ -137,7 +137,7 @@ _mm_movehdup_ps(__m128 __a)
   return __builtin_shufflevector((__v4sf)__a, (__v4sf)__a, 1, 1, 3, 3);
 }
 
-/// \brief Duplicates low-order (even-indexed) values from a 128-bit vector of
+/// \brief Duplicates even-indexed values from a 128-bit vector of
 ///    [4 x float] to float values stored in a 128-bit vector of [4 x float].
 ///
 /// \headerfile <x86intrin.h>
diff --git a/lib/Headers/smmintrin.h b/lib/Headers/smmintrin.h
index c2fa5a452bcec..e02775cea358b 100644
--- a/lib/Headers/smmintrin.h
+++ b/lib/Headers/smmintrin.h
@@ -648,7 +648,7 @@ _mm_mul_epi32 (__m128i __V1, __m128i __V2)
 ///    input vectors are used as an input for dot product; otherwise that input
 ///    is treated as zero. Bits [1:0] determine which elements of the result
 ///    will receive a copy of the final dot product, with bit [0] corresponding
-///    to the lowest element and bit [3] corresponding to the highest element of
+///    to the lowest element and bit [1] corresponding to the highest element of
 ///    each [2 x double] vector. If a bit is set, the dot product is returned in
 ///    the corresponding element; otherwise that element is set to zero.
 #define _mm_dp_pd(X, Y, M) __extension__ ({\
@@ -866,8 +866,8 @@ _mm_max_epu32 (__m128i __V1, __m128i __V2)
 ///      11: Copies the selected bits from \a Y to result bits [127:96]. \n
 ///    Bits[3:0]: If any of these bits are set, the corresponding result
 ///    element is cleared.
-/// \returns A 128-bit vector of [4 x float] containing the copied single-
-///    precision floating point elements from the operands.
+/// \returns A 128-bit vector of [4 x float] containing the copied
+///    single-precision floating point elements from the operands.
 #define _mm_insert_ps(X, Y, N) __builtin_ia32_insertps128((X), (Y), (N))
 
 /// \brief Extracts a 32-bit integer from a 128-bit vector of [4 x float] and
diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 2a999399fb500..127e18439b8e0 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -43,13 +43,13 @@ using namespace clang;
 ///
 /// Called type-id in C++.
 TypeResult Parser::ParseTypeName(SourceRange *Range,
-                                 Declarator::TheContext Context,
+                                 DeclaratorContext Context,
                                  AccessSpecifier AS,
                                  Decl **OwnedType,
                                  ParsedAttributes *Attrs) {
   DeclSpecContext DSC = getDeclSpecContextFromDeclaratorContext(Context);
-  if (DSC == DSC_normal)
-    DSC = DSC_type_specifier;
+  if (DSC == DeclSpecContext::DSC_normal)
+    DSC = DeclSpecContext::DSC_type_specifier;
 
   // Parse the common declaration-specifiers piece.
   DeclSpec DS(AttrFactory);
@@ -1639,7 +1639,7 @@ void Parser::stripTypeAttributesOffDeclSpec(ParsedAttributesWithRange &Attrs,
 
 /// ParseDeclaration - Parse a full 'declaration', which consists of
 /// declaration-specifiers, some number of declarators, and a semicolon.
-/// 'Context' should be a Declarator::TheContext value.  This returns the
+/// 'Context' should be a DeclaratorContext value.  This returns the
 /// location of the semicolon in DeclEnd.
 ///
 ///       declaration: [C99 6.7]
@@ -1653,7 +1653,7 @@ void Parser::stripTypeAttributesOffDeclSpec(ParsedAttributesWithRange &Attrs,
 /// [C++11/C11] static_assert-declaration
 ///         others... [FIXME]
 ///
-Parser::DeclGroupPtrTy Parser::ParseDeclaration(unsigned Context,
+Parser::DeclGroupPtrTy Parser::ParseDeclaration(DeclaratorContext Context,
                                                 SourceLocation &DeclEnd,
                                           ParsedAttributesWithRange &attrs) {
   ParenBraceBracketBalancer BalancerRAIIObj(*this);
@@ -1714,7 +1714,7 @@ Parser::DeclGroupPtrTy Parser::ParseDeclaration(unsigned Context,
 /// of a simple-declaration. If we find that we are, we also parse the
 /// for-range-initializer, and place it here.
 Parser::DeclGroupPtrTy
-Parser::ParseSimpleDeclaration(unsigned Context,
+Parser::ParseSimpleDeclaration(DeclaratorContext Context,
                                SourceLocation &DeclEnd,
                                ParsedAttributesWithRange &Attrs,
                                bool RequireSemi, ForRangeInit *FRI) {
@@ -1753,7 +1753,7 @@ Parser::ParseSimpleDeclaration(unsigned Context,
 
 /// Returns true if this might be the start of a declarator, or a common typo
 /// for a declarator.
-bool Parser::MightBeDeclarator(unsigned Context) {
+bool Parser::MightBeDeclarator(DeclaratorContext Context) {
   switch (Tok.getKind()) {
   case tok::annot_cxxscope:
   case tok::annot_template_id:
@@ -1772,11 +1772,12 @@ bool Parser::MightBeDeclarator(unsigned Context) {
     return getLangOpts().CPlusPlus;
 
   case tok::l_square: // Might be an attribute on an unnamed bit-field.
-    return Context == Declarator::MemberContext && getLangOpts().CPlusPlus11 &&
-           NextToken().is(tok::l_square);
+    return Context == DeclaratorContext::MemberContext &&
+           getLangOpts().CPlusPlus11 && NextToken().is(tok::l_square);
 
   case tok::colon: // Might be a typo for '::' or an unnamed bit-field.
-    return Context == Declarator::MemberContext || getLangOpts().CPlusPlus;
+    return Context == DeclaratorContext::MemberContext ||
+           getLangOpts().CPlusPlus;
 
   case tok::identifier:
     switch (NextToken().getKind()) {
@@ -1802,8 +1803,9 @@ bool Parser::MightBeDeclarator(unsigned Context) {
       // At namespace scope, 'identifier:' is probably a typo for 'identifier::'
       // and in block scope it's probably a label. Inside a class definition,
       // this is a bit-field.
-      return Context == Declarator::MemberContext ||
-             (getLangOpts().CPlusPlus && Context == Declarator::FileContext);
+      return Context == DeclaratorContext::MemberContext ||
+             (getLangOpts().CPlusPlus &&
+              Context == DeclaratorContext::FileContext);
 
     case tok::identifier: // Possible virt-specifier.
       return getLangOpts().CPlusPlus11 && isCXX11VirtSpecifier(NextToken());
@@ -1902,11 +1904,11 @@ void Parser::SkipMalformedDecl() {
 /// definition or a group of object declarations, actually parse the
 /// result.
 Parser::DeclGroupPtrTy Parser::ParseDeclGroup(ParsingDeclSpec &DS,
-                                              unsigned Context,
+                                              DeclaratorContext Context,
                                               SourceLocation *DeclEnd,
                                               ForRangeInit *FRI) {
   // Parse the first declarator.
-  ParsingDeclarator D(*this, DS, static_cast<Declarator::TheContext>(Context));
+  ParsingDeclarator D(*this, DS, Context);
   ParseDeclarator(D);
 
   // Bail out if the first declarator didn't seem well-formed.
@@ -1953,7 +1955,7 @@ Parser::DeclGroupPtrTy Parser::ParseDeclGroup(ParsingDeclSpec &DS,
     // Function definitions are only allowed at file scope and in C++ classes.
     // The C++ inline method definition case is handled elsewhere, so we only
     // need to handle the file scope definition case.
-    if (Context == Declarator::FileContext) {
+    if (Context == DeclaratorContext::FileContext) {
       if (isStartOfFunctionDefinition(D)) {
         if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) {
           Diag(Tok, diag::err_function_declared_typedef);
@@ -2024,7 +2026,7 @@ Parser::DeclGroupPtrTy Parser::ParseDeclGroup(ParsingDeclSpec &DS,
   if (FirstDecl)
     DeclsInGroup.push_back(FirstDecl);
 
-  bool ExpectSemi = Context != Declarator::ForContext;
+  bool ExpectSemi = Context != DeclaratorContext::ForContext;
   
   // If we don't have a comma, it is either the end of the list (a ';') or an
   // error, bail out.
@@ -2070,7 +2072,7 @@ Parser::DeclGroupPtrTy Parser::ParseDeclGroup(ParsingDeclSpec &DS,
     *DeclEnd = Tok.getLocation();
 
   if (ExpectSemi &&
-      ExpectAndConsumeSemi(Context == Declarator::FileContext
+      ExpectAndConsumeSemi(Context == DeclaratorContext::FileContext
                            ? diag::err_invalid_token_after_toplevel_declarator
                            : diag::err_expected_semi_declaration)) {
     // Okay, there was no semicolon and one was expected.  If we see a
@@ -2199,7 +2201,7 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
       // FIXME: This check should be for a variable template instantiation only.
 
       // Check that this is a valid instantiation
-      if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
+      if (D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId) {
         // If the declarator-id is not a template-id, issue a diagnostic and
         // recover by ignoring the 'template' keyword.
         Diag(Tok, diag::err_template_defn_explicit_instantiation)
@@ -2273,8 +2275,8 @@ Decl *Parser::ParseDeclarationAfterDeclaratorAndAttributes(
       if (Init.isInvalid()) {
         SmallVector<tok::TokenKind, 2> StopTokens;
         StopTokens.push_back(tok::comma);
-        if (D.getContext() == Declarator::ForContext ||
-            D.getContext() == Declarator::InitStmtContext)
+        if (D.getContext() == DeclaratorContext::ForContext ||
+            D.getContext() == DeclaratorContext::InitStmtContext)
           StopTokens.push_back(tok::r_paren);
         SkipUntil(StopTokens, StopAtSemi | StopBeforeMatch);
         Actions.ActOnInitializerError(ThisDecl);
@@ -2397,7 +2399,7 @@ void Parser::ParseSpecifierQualifierList(DeclSpec &DS, AccessSpecifier AS,
   }
 
   // Issue diagnostic and remove constexpr specfier if present.
-  if (DS.isConstexprSpecified() && DSC != DSC_condition) {
+  if (DS.isConstexprSpecified() && DSC != DeclSpecContext::DSC_condition) {
     Diag(DS.getConstexprSpecLoc(), diag::err_typename_invalid_constexpr);
     DS.ClearConstexprSpec();
   }
@@ -2486,7 +2488,7 @@ bool Parser::ParseImplicitInt(DeclSpec &DS, CXXScopeSpec *SS,
     // classes.
     if (ParsedType T = Actions.ActOnMSVCUnknownTypeName(
             *Tok.getIdentifierInfo(), Tok.getLocation(),
-            DSC == DSC_template_type_arg)) {
+            DSC == DeclSpecContext::DSC_template_type_arg)) {
       const char *PrevSpec;
       unsigned DiagID;
       DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec, DiagID, T,
@@ -2540,18 +2542,20 @@ bool Parser::ParseImplicitInt(DeclSpec &DS, CXXScopeSpec *SS,
 
       // Parse this as a tag as if the missing tag were present.
       if (TagKind == tok::kw_enum)
-        ParseEnumSpecifier(Loc, DS, TemplateInfo, AS, DSC_normal);
+        ParseEnumSpecifier(Loc, DS, TemplateInfo, AS,
+                           DeclSpecContext::DSC_normal);
       else
         ParseClassSpecifier(TagKind, Loc, DS, TemplateInfo, AS,
-                            /*EnteringContext*/ false, DSC_normal, Attrs);
+                            /*EnteringContext*/ false,
+                            DeclSpecContext::DSC_normal, Attrs);
       return true;
     }
   }
 
   // Determine whether this identifier could plausibly be the name of something
   // being declared (with a missing type).
-  if (!isTypeSpecifier(DSC) &&
-      (!SS || DSC == DSC_top_level || DSC == DSC_class)) {
+  if (!isTypeSpecifier(DSC) && (!SS || DSC == DeclSpecContext::DSC_top_level ||
+                                DSC == DeclSpecContext::DSC_class)) {
     // Look ahead to the next token to try to figure out what this declaration
     // was supposed to be.
     switch (NextToken().getKind()) {
@@ -2575,7 +2579,8 @@ bool Parser::ParseImplicitInt(DeclSpec &DS, CXXScopeSpec *SS,
 
       // If we're in a context where we could be declaring a constructor,
       // check whether this is a constructor declaration with a bogus name.
-      if (DSC == DSC_class || (DSC == DSC_top_level && SS)) {
+      if (DSC == DeclSpecContext::DSC_class ||
+          (DSC == DeclSpecContext::DSC_top_level && SS)) {
         IdentifierInfo *II = Tok.getIdentifierInfo();
         if (Actions.isCurrentClassNameTypo(II, SS)) {
           Diag(Loc, diag::err_constructor_bad_name)
@@ -2655,23 +2660,23 @@ bool Parser::ParseImplicitInt(DeclSpec &DS, CXXScopeSpec *SS,
 /// context.
 ///
 /// \param Context the declarator context, which is one of the
-/// Declarator::TheContext enumerator values.
+/// DeclaratorContext enumerator values.
 Parser::DeclSpecContext
-Parser::getDeclSpecContextFromDeclaratorContext(unsigned Context) {
-  if (Context == Declarator::MemberContext)
-    return DSC_class;
-  if (Context == Declarator::FileContext)
-    return DSC_top_level;
-  if (Context == Declarator::TemplateParamContext)
-    return DSC_template_param;
-  if (Context == Declarator::TemplateTypeArgContext)
-    return DSC_template_type_arg;
-  if (Context == Declarator::TrailingReturnContext)
-    return DSC_trailing;
-  if (Context == Declarator::AliasDeclContext ||
-      Context == Declarator::AliasTemplateContext)
-    return DSC_alias_declaration;
-  return DSC_normal;
+Parser::getDeclSpecContextFromDeclaratorContext(DeclaratorContext Context) {
+  if (Context == DeclaratorContext::MemberContext)
+    return DeclSpecContext::DSC_class;
+  if (Context == DeclaratorContext::FileContext)
+    return DeclSpecContext::DSC_top_level;
+  if (Context == DeclaratorContext::TemplateParamContext)
+    return DeclSpecContext::DSC_template_param;
+  if (Context == DeclaratorContext::TemplateTypeArgContext)
+    return DeclSpecContext::DSC_template_type_arg;
+  if (Context == DeclaratorContext::TrailingReturnContext)
+    return DeclSpecContext::DSC_trailing;
+  if (Context == DeclaratorContext::AliasDeclContext ||
+      Context == DeclaratorContext::AliasTemplateContext)
+    return DeclSpecContext::DSC_alias_declaration;
+  return DeclSpecContext::DSC_normal;
 }
 
 /// ParseAlignArgument - Parse the argument to an alignment-specifier.
@@ -2751,7 +2756,8 @@ Parser::DiagnoseMissingSemiAfterTagDefinition(DeclSpec &DS, AccessSpecifier AS,
                                               LateParsedAttrList *LateAttrs) {
   assert(DS.hasTagDefinition() && "shouldn't call this");
 
-  bool EnteringContext = (DSContext == DSC_class || DSContext == DSC_top_level);
+  bool EnteringContext = (DSContext == DeclSpecContext::DSC_class ||
+                          DSContext == DeclSpecContext::DSC_top_level);
 
   if (getLangOpts().CPlusPlus &&
       Tok.isOneOf(tok::identifier, tok::coloncolon, tok::kw_decltype,
@@ -2885,7 +2891,8 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
     DS.SetRangeEnd(SourceLocation());
   }
 
-  bool EnteringContext = (DSContext == DSC_class || DSContext == DSC_top_level);
+  bool EnteringContext = (DSContext == DeclSpecContext::DSC_class ||
+                          DSContext == DeclSpecContext::DSC_top_level);
   bool AttrsLastTime = false;
   ParsedAttributesWithRange attrs(AttrFactory);
   // We use Sema's policy to get bool macros right.
@@ -2955,8 +2962,8 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
                                           Scope::FunctionPrototypeScope |
                                           Scope::AtCatchScope)) == 0;
         bool AllowNestedNameSpecifiers
-          = DSContext == DSC_top_level ||
-            (DSContext == DSC_class && DS.isFriendSpecified());
+          = DSContext == DeclSpecContext::DSC_top_level ||
+            (DSContext == DeclSpecContext::DSC_class && DS.isFriendSpecified());
 
         Actions.CodeCompleteDeclSpec(getCurScope(), DS,
                                      AllowNonIdentifiers,
@@ -2967,9 +2974,9 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       if (getCurScope()->getFnParent() || getCurScope()->getBlockParent())
         CCC = Sema::PCC_LocalDeclarationSpecifiers;
       else if (TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate)
-        CCC = DSContext == DSC_class? Sema::PCC_MemberTemplate
-                                    : Sema::PCC_Template;
-      else if (DSContext == DSC_class)
+        CCC = DSContext == DeclSpecContext::DSC_class ? Sema::PCC_MemberTemplate
+                                                      : Sema::PCC_Template;
+      else if (DSContext == DeclSpecContext::DSC_class)
         CCC = Sema::PCC_Class;
       else if (CurParsedObjCImpl)
         CCC = Sema::PCC_ObjCImplementation;
@@ -3013,10 +3020,11 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
         // To improve diagnostics for this case, parse the declaration as a
         // constructor (and reject the extra template arguments later).
         TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Next);
-        if ((DSContext == DSC_top_level || DSContext == DSC_class) &&
+        if ((DSContext == DeclSpecContext::DSC_top_level ||
+             DSContext == DeclSpecContext::DSC_class) &&
             TemplateId->Name &&
             Actions.isCurrentClassName(*TemplateId->Name, getCurScope(), &SS) &&
-            isConstructorDeclarator(/*Unqualified*/false)) {
+            isConstructorDeclarator(/*Unqualified*/ false)) {
           // The user meant this to be an out-of-line constructor
           // definition, but template arguments are not allowed
           // there.  Just allow this as a constructor; we'll
@@ -3055,7 +3063,8 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       // Check whether this is a constructor declaration. If we're in a
       // context where the identifier could be a class name, and it has the
       // shape of a constructor declaration, process it as one.
-      if ((DSContext == DSC_top_level || DSContext == DSC_class) &&
+      if ((DSContext == DeclSpecContext::DSC_top_level ||
+           DSContext == DeclSpecContext::DSC_class) &&
           Actions.isCurrentClassName(*Next.getIdentifierInfo(), getCurScope(),
                                      &SS) &&
           isConstructorDeclarator(/*Unqualified*/ false))
@@ -3193,7 +3202,8 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       if (DS.isTypeAltiVecVector())
         goto DoneWithDeclSpec;
 
-      if (DSContext == DSC_objc_method_result && isObjCInstancetype()) {
+      if (DSContext == DeclSpecContext::DSC_objc_method_result &&
+          isObjCInstancetype()) {
         ParsedType TypeRep = Actions.ActOnObjCInstanceType(Loc);
         assert(TypeRep);
         isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typename, Loc, PrevSpec,
@@ -3227,7 +3237,7 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
 
       // If we're in a context where the identifier could be a class name,
       // check whether this is a constructor declaration.
-      if (getLangOpts().CPlusPlus && DSContext == DSC_class &&
+      if (getLangOpts().CPlusPlus && DSContext == DeclSpecContext::DSC_class &&
           Actions.isCurrentClassName(*Tok.getIdentifierInfo(), getCurScope()) &&
           isConstructorDeclarator(/*Unqualified*/true))
         goto DoneWithDeclSpec;
@@ -3235,7 +3245,8 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       // Likewise, if this is a context where the identifier could be a template
       // name, check whether this is a deduction guide declaration.
       if (getLangOpts().CPlusPlus17 &&
-          (DSContext == DSC_class || DSContext == DSC_top_level) &&
+          (DSContext == DeclSpecContext::DSC_class ||
+           DSContext == DeclSpecContext::DSC_top_level) &&
           Actions.isDeductionGuideName(getCurScope(), *Tok.getIdentifierInfo(),
                                        Tok.getLocation()) &&
           isConstructorDeclarator(/*Unqualified*/ true,
@@ -3281,7 +3292,7 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       // If we're in a context where the template-id could be a
       // constructor name or specialization, check whether this is a
       // constructor declaration.
-      if (getLangOpts().CPlusPlus && DSContext == DSC_class &&
+      if (getLangOpts().CPlusPlus && DSContext == DeclSpecContext::DSC_class &&
           Actions.isCurrentClassName(*TemplateId->Name, getCurScope()) &&
           isConstructorDeclarator(TemplateId->SS.isEmpty()))
         goto DoneWithDeclSpec;
@@ -3451,7 +3462,7 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
 
     // friend
     case tok::kw_friend:
-      if (DSContext == DSC_class)
+      if (DSContext == DeclSpecContext::DSC_class)
         isInvalid = DS.SetFriendSpec(Loc, PrevSpec, DiagID);
       else {
         PrevSpec = ""; // not actually used by the diagnostic
@@ -4070,7 +4081,7 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
   SuppressAccessChecks diagsFromTag(*this, shouldDelayDiagsInTag);
 
   // Enum definitions should not be parsed in a trailing-return-type.
-  bool AllowDeclaration = DSC != DSC_trailing;
+  bool AllowDeclaration = DSC != DeclSpecContext::DSC_trailing;
 
   bool AllowFixedUnderlyingType = AllowDeclaration &&
     (getLangOpts().CPlusPlus11 || getLangOpts().MicrosoftExt ||
@@ -4296,14 +4307,14 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
   bool IsDependent = false;
   const char *PrevSpec = nullptr;
   unsigned DiagID;
-  Decl *TagDecl = Actions.ActOnTag(getCurScope(), DeclSpec::TST_enum, TUK,
-                                   StartLoc, SS, Name, NameLoc, attrs.getList(),
-                                   AS, DS.getModulePrivateSpecLoc(), TParams,
-                                   Owned, IsDependent, ScopedEnumKWLoc,
-                                   IsScopedUsingClassTag, BaseType,
-                                   DSC == DSC_type_specifier,
-                                   DSC == DSC_template_param ||
-                                   DSC == DSC_template_type_arg, &SkipBody);
+  Decl *TagDecl = Actions.ActOnTag(
+      getCurScope(), DeclSpec::TST_enum, TUK, StartLoc, SS, Name, NameLoc,
+      attrs.getList(), AS, DS.getModulePrivateSpecLoc(), TParams, Owned,
+      IsDependent, ScopedEnumKWLoc, IsScopedUsingClassTag, BaseType,
+      DSC == DeclSpecContext::DSC_type_specifier,
+      DSC == DeclSpecContext::DSC_template_param ||
+          DSC == DeclSpecContext::DSC_template_type_arg,
+      &SkipBody);
 
   if (SkipBody.ShouldSkip) {
     assert(TUK == Sema::TUK_Definition && "can only skip a definition");
@@ -5175,7 +5186,7 @@ void Parser::ParseDeclarator(Declarator &D) {
 }
 
 static bool isPtrOperatorToken(tok::TokenKind Kind, const LangOptions &Lang,
-                               unsigned TheContext) {
+                               DeclaratorContext TheContext) {
   if (Kind == tok::star || Kind == tok::caret)
     return true;
 
@@ -5194,8 +5205,9 @@ static bool isPtrOperatorToken(tok::TokenKind Kind, const LangOptions &Lang,
   // (The same thing can in theory happen after a trailing-return-type, but
   // since those are a C++11 feature, there is no rejects-valid issue there.)
   if (Kind == tok::ampamp)
-    return Lang.CPlusPlus11 || (TheContext != Declarator::ConversionIdContext &&
-                                TheContext != Declarator::CXXNewContext);
+    return Lang.CPlusPlus11 ||
+           (TheContext != DeclaratorContext::ConversionIdContext &&
+            TheContext != DeclaratorContext::CXXNewContext);
 
   return false;
 }
@@ -5249,8 +5261,9 @@ void Parser::ParseDeclaratorInternal(Declarator &D,
        (Tok.is(tok::identifier) &&
         (NextToken().is(tok::coloncolon) || NextToken().is(tok::less))) ||
        Tok.is(tok::annot_cxxscope))) {
-    bool EnteringContext = D.getContext() == Declarator::FileContext ||
-                           D.getContext() == Declarator::MemberContext;
+    bool EnteringContext =
+        D.getContext() == DeclaratorContext::FileContext ||
+        D.getContext() == DeclaratorContext::MemberContext;
     CXXScopeSpec SS;
     ParseOptionalCXXScopeSpecifier(SS, nullptr, EnteringContext);
 
@@ -5316,9 +5329,9 @@ void Parser::ParseDeclaratorInternal(Declarator &D,
     // GNU attributes are not allowed here in a new-type-id, but Declspec and
     // C++11 attributes are allowed.
     unsigned Reqs = AR_CXX11AttributesParsed | AR_DeclspecAttributesParsed |
-                            ((D.getContext() != Declarator::CXXNewContext)
-                                 ? AR_GNUAttributesParsed
-                                 : AR_GNUAttributesParsedAndRejected);
+                    ((D.getContext() != DeclaratorContext::CXXNewContext)
+                         ? AR_GNUAttributesParsed
+                         : AR_GNUAttributesParsedAndRejected);
     ParseTypeQualifierListOpt(DS, Reqs, true, !D.mayOmitIdentifier());
     D.ExtendWithDeclSpec(DS);
 
@@ -5470,15 +5483,16 @@ void Parser::ParseDirectDeclarator(Declarator &D) {
     // Don't parse FOO:BAR as if it were a typo for FOO::BAR inside a class, in
     // this context it is a bitfield. Also in range-based for statement colon
     // may delimit for-range-declaration.
-    ColonProtectionRAIIObject X(*this,
-                                D.getContext() == Declarator::MemberContext ||
-                                    (D.getContext() == Declarator::ForContext &&
-                                     getLangOpts().CPlusPlus11));
+    ColonProtectionRAIIObject X(
+        *this, D.getContext() == DeclaratorContext::MemberContext ||
+                   (D.getContext() == DeclaratorContext::ForContext &&
+                    getLangOpts().CPlusPlus11));
 
     // ParseDeclaratorInternal might already have parsed the scope.
     if (D.getCXXScopeSpec().isEmpty()) {
-      bool EnteringContext = D.getContext() == Declarator::FileContext ||
-                             D.getContext() == Declarator::MemberContext;
+      bool EnteringContext =
+          D.getContext() == DeclaratorContext::FileContext ||
+          D.getContext() == DeclaratorContext::MemberContext;
       ParseOptionalCXXScopeSpecifier(D.getCXXScopeSpec(), nullptr,
                                      EnteringContext);
     }
@@ -5507,9 +5521,9 @@ void Parser::ParseDirectDeclarator(Declarator &D) {
     //   been expanded or contains auto; otherwise, it is parsed as part of the
     //   parameter-declaration-clause.
     if (Tok.is(tok::ellipsis) && D.getCXXScopeSpec().isEmpty() &&
-        !((D.getContext() == Declarator::PrototypeContext ||
-           D.getContext() == Declarator::LambdaExprParameterContext ||
-           D.getContext() == Declarator::BlockLiteralContext) &&
+        !((D.getContext() == DeclaratorContext::PrototypeContext ||
+           D.getContext() == DeclaratorContext::LambdaExprParameterContext ||
+           D.getContext() == DeclaratorContext::BlockLiteralContext) &&
           NextToken().is(tok::r_paren) &&
           !D.hasGroupingParens() &&
           !Actions.containsUnexpandedParameterPacks(D) &&
@@ -5541,14 +5555,15 @@ void Parser::ParseDirectDeclarator(Declarator &D) {
         AllowDeductionGuide = false;
       } else if (D.getCXXScopeSpec().isSet()) {
         AllowConstructorName =
-          (D.getContext() == Declarator::FileContext ||
-           D.getContext() == Declarator::MemberContext);
+          (D.getContext() == DeclaratorContext::FileContext ||
+           D.getContext() == DeclaratorContext::MemberContext);
         AllowDeductionGuide = false;
       } else {
-        AllowConstructorName = (D.getContext() == Declarator::MemberContext);
+        AllowConstructorName =
+            (D.getContext() == DeclaratorContext::MemberContext);
         AllowDeductionGuide = 
-          (D.getContext() == Declarator::FileContext ||
-           D.getContext() == Declarator::MemberContext);
+          (D.getContext() == DeclaratorContext::FileContext ||
+           D.getContext() == DeclaratorContext::MemberContext);
       }
 
       SourceLocation TemplateKWLoc;
@@ -5604,15 +5619,15 @@ void Parser::ParseDirectDeclarator(Declarator &D) {
       // An identifier within parens is unlikely to be intended to be anything
       // other than a name being "declared".
       DiagnoseIdentifier = true;
-    else if (D.getContext() == Declarator::TemplateTypeArgContext)
+    else if (D.getContext() == DeclaratorContext::TemplateTypeArgContext)
       // T<int N> is an accidental identifier; T<int N indicates a missing '>'.
       DiagnoseIdentifier =
           NextToken().isOneOf(tok::comma, tok::greater, tok::greatergreater);
-    else if (D.getContext() == Declarator::AliasDeclContext ||
-             D.getContext() == Declarator::AliasTemplateContext)
+    else if (D.getContext() == DeclaratorContext::AliasDeclContext ||
+             D.getContext() == DeclaratorContext::AliasTemplateContext)
       // The most likely error is that the ';' was forgotten.
       DiagnoseIdentifier = NextToken().isOneOf(tok::comma, tok::semi);
-    else if (D.getContext() == Declarator::TrailingReturnContext &&
+    else if (D.getContext() == DeclaratorContext::TrailingReturnContext &&
              !isCXX11VirtSpecifier(Tok))
       DiagnoseIdentifier = NextToken().isOneOf(
           tok::comma, tok::semi, tok::equal, tok::l_brace, tok::kw_try);
@@ -5659,7 +5674,7 @@ void Parser::ParseDirectDeclarator(Declarator &D) {
       LLVM_BUILTIN_TRAP;
     if (Tok.is(tok::l_square))
       return ParseMisplacedBracketDeclarator(D);
-    if (D.getContext() == Declarator::MemberContext) {
+    if (D.getContext() == DeclaratorContext::MemberContext) {
       // Objective-C++: Detect C++ keywords and try to prevent further errors by
       // treating these keyword as valid member names.
       if (getLangOpts().ObjC1 && getLangOpts().CPlusPlus &&
@@ -6042,9 +6057,9 @@ void Parser::ParseFunctionDeclarator(Declarator &D,
       bool IsCXX11MemberFunction =
         getLangOpts().CPlusPlus11 &&
         D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
-        (D.getContext() == Declarator::MemberContext
+        (D.getContext() == DeclaratorContext::MemberContext
          ? !D.getDeclSpec().isFriendSpecified()
-         : D.getContext() == Declarator::FileContext &&
+         : D.getContext() == DeclaratorContext::FileContext &&
            D.getCXXScopeSpec().isValid() &&
            Actions.CurContext->isRecord());
       Sema::CXXThisScopeRAII ThisScope(Actions,
@@ -6309,10 +6324,10 @@ void Parser::ParseParameterDeclarationClause(
     // Parse the declarator.  This is "PrototypeContext" or 
     // "LambdaExprParameterContext", because we must accept either 
     // 'declarator' or 'abstract-declarator' here.
-    Declarator ParmDeclarator(DS, 
-              D.getContext() == Declarator::LambdaExprContext ?
-                                  Declarator::LambdaExprParameterContext : 
-                                                Declarator::PrototypeContext);
+    Declarator ParmDeclarator(
+        DS, D.getContext() == DeclaratorContext::LambdaExprContext
+                ? DeclaratorContext::LambdaExprParameterContext
+                : DeclaratorContext::PrototypeContext);
     ParseDeclarator(ParmDeclarator);
 
     // Parse GNU attributes, if present.
@@ -6355,7 +6370,7 @@ void Parser::ParseParameterDeclarationClause(
         SourceLocation EqualLoc = Tok.getLocation();
 
         // Parse the default argument
-        if (D.getContext() == Declarator::MemberContext) {
+        if (D.getContext() == DeclaratorContext::MemberContext) {
           // If we're inside a class definition, cache the tokens
           // corresponding to the default argument. We'll actually parse
           // them when we see the end of the class definition.
diff --git a/lib/Parse/ParseDeclCXX.cpp b/lib/Parse/ParseDeclCXX.cpp
index 44e7a3512098b..68b73ca1d25f2 100644
--- a/lib/Parse/ParseDeclCXX.cpp
+++ b/lib/Parse/ParseDeclCXX.cpp
@@ -55,7 +55,7 @@ using namespace clang;
 ///       namespace-alias-definition:  [C++ 7.3.2: namespace.alias]
 ///         'namespace' identifier '=' qualified-namespace-specifier ';'
 ///
-Parser::DeclGroupPtrTy Parser::ParseNamespace(unsigned Context,
+Parser::DeclGroupPtrTy Parser::ParseNamespace(DeclaratorContext Context,
                                               SourceLocation &DeclEnd,
                                               SourceLocation InlineLoc) {
   assert(Tok.is(tok::kw_namespace) && "Not a namespace!");
@@ -307,7 +307,7 @@ Decl *Parser::ParseNamespaceAlias(SourceLocation NamespaceLoc,
 ///         'extern' string-literal '{' declaration-seq[opt] '}'
 ///         'extern' string-literal declaration
 ///
-Decl *Parser::ParseLinkage(ParsingDeclSpec &DS, unsigned Context) {
+Decl *Parser::ParseLinkage(ParsingDeclSpec &DS, DeclaratorContext Context) {
   assert(isTokenStringLiteral() && "Not a string literal!");
   ExprResult Lang = ParseStringLiteralExpression(false);
 
@@ -434,7 +434,7 @@ Decl *Parser::ParseExportDeclaration() {
 /// ParseUsingDirectiveOrDeclaration - Parse C++ using using-declaration or
 /// using-directive. Assumes that current token is 'using'.
 Parser::DeclGroupPtrTy
-Parser::ParseUsingDirectiveOrDeclaration(unsigned Context,
+Parser::ParseUsingDirectiveOrDeclaration(DeclaratorContext Context,
                                          const ParsedTemplateInfo &TemplateInfo,
                                          SourceLocation &DeclEnd,
                                          ParsedAttributesWithRange &attrs) {
@@ -482,7 +482,7 @@ Parser::ParseUsingDirectiveOrDeclaration(unsigned Context,
 ///        'using' 'namespace' ::[opt] nested-name-specifier[opt]
 ///                 namespace-name attributes[opt] ;
 ///
-Decl *Parser::ParseUsingDirective(unsigned Context,
+Decl *Parser::ParseUsingDirective(DeclaratorContext Context,
                                   SourceLocation UsingLoc,
                                   SourceLocation &DeclEnd,
                                   ParsedAttributes &attrs) {
@@ -551,7 +551,8 @@ Decl *Parser::ParseUsingDirective(unsigned Context,
 ///     using-declarator:
 ///       'typename'[opt] nested-name-specifier unqualified-id
 ///
-bool Parser::ParseUsingDeclarator(unsigned Context, UsingDeclarator &D) {
+bool Parser::ParseUsingDeclarator(DeclaratorContext Context,
+                                  UsingDeclarator &D) {
   D.clear();
 
   // Ignore optional 'typename'.
@@ -582,7 +583,8 @@ bool Parser::ParseUsingDeclarator(unsigned Context, UsingDeclarator &D) {
   //   or the simple-template-id's template-name in the last component of the
   //   nested-name-specifier, the name is [...] considered to name the
   //   constructor.
-  if (getLangOpts().CPlusPlus11 && Context == Declarator::MemberContext &&
+  if (getLangOpts().CPlusPlus11 &&
+      Context == DeclaratorContext::MemberContext &&
       Tok.is(tok::identifier) &&
       (NextToken().is(tok::semi) || NextToken().is(tok::comma) ||
        NextToken().is(tok::ellipsis)) &&
@@ -629,7 +631,7 @@ bool Parser::ParseUsingDeclarator(unsigned Context, UsingDeclarator &D) {
 ///       'using' identifier attribute-specifier-seq[opt] = type-id ;
 ///
 Parser::DeclGroupPtrTy
-Parser::ParseUsingDeclaration(unsigned Context,
+Parser::ParseUsingDeclaration(DeclaratorContext Context,
                               const ParsedTemplateInfo &TemplateInfo,
                               SourceLocation UsingLoc, SourceLocation &DeclEnd,
                               AccessSpecifier AS) {
@@ -699,7 +701,7 @@ Parser::ParseUsingDeclaration(unsigned Context,
       // "typename" keyword is allowed for identifiers only,
       // because it may be a type definition.
       if (D.TypenameLoc.isValid() &&
-          D.Name.getKind() != UnqualifiedId::IK_Identifier) {
+          D.Name.getKind() != UnqualifiedIdKind::IK_Identifier) {
         Diag(D.Name.getSourceRange().getBegin(),
              diag::err_typename_identifiers_only)
             << FixItHint::CreateRemoval(SourceRange(D.TypenameLoc));
@@ -753,7 +755,7 @@ Decl *Parser::ParseAliasDeclarationAfterDeclarator(
   // Type alias templates cannot be specialized.
   int SpecKind = -1;
   if (TemplateInfo.Kind == ParsedTemplateInfo::Template &&
-      D.Name.getKind() == UnqualifiedId::IK_TemplateId)
+      D.Name.getKind() == UnqualifiedIdKind::IK_TemplateId)
     SpecKind = 0;
   if (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitSpecialization)
     SpecKind = 1;
@@ -773,7 +775,7 @@ Decl *Parser::ParseAliasDeclarationAfterDeclarator(
   }
 
   // Name must be an identifier.
-  if (D.Name.getKind() != UnqualifiedId::IK_Identifier) {
+  if (D.Name.getKind() != UnqualifiedIdKind::IK_Identifier) {
     Diag(D.Name.StartLocation, diag::err_alias_declaration_not_identifier);
     // No removal fixit: can't recover from this.
     SkipUntil(tok::semi);
@@ -791,11 +793,11 @@ Decl *Parser::ParseAliasDeclarationAfterDeclarator(
       << FixItHint::CreateRemoval(SourceRange(D.EllipsisLoc));
 
   Decl *DeclFromDeclSpec = nullptr;
-  TypeResult TypeAlias =
-      ParseTypeName(nullptr,
-                    TemplateInfo.Kind ? Declarator::AliasTemplateContext
-                                      : Declarator::AliasDeclContext,
-                    AS, &DeclFromDeclSpec, &Attrs);
+  TypeResult TypeAlias = ParseTypeName(
+      nullptr,
+      TemplateInfo.Kind ? DeclaratorContext::AliasTemplateContext
+                        : DeclaratorContext::AliasDeclContext,
+      AS, &DeclFromDeclSpec, &Attrs);
   if (OwnedType)
     *OwnedType = DeclFromDeclSpec;
 
@@ -1094,7 +1096,7 @@ TypeResult Parser::ParseBaseTypeSpecifier(SourceLocation &BaseLoc,
 
     EndLocation = ParseDecltypeSpecifier(DS);
 
-    Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+    Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
     return Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
   }
 
@@ -1195,7 +1197,7 @@ TypeResult Parser::ParseBaseTypeSpecifier(SourceLocation &BaseLoc,
   DS.SetTypeSpecType(TST_typename, IdLoc, PrevSpec, DiagID, Type,
                      Actions.getASTContext().getPrintingPolicy());
 
-  Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+  Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
   return Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
 }
 
@@ -1612,14 +1614,15 @@ void Parser::ParseClassSpecifier(tok::TokenKind TagTokKind,
   //   new struct s;
   // or
   //   &T::operator struct s;
-  // For these, DSC is DSC_type_specifier or DSC_alias_declaration.
+  // For these, DSC is DeclSpecContext::DSC_type_specifier or
+  // DeclSpecContext::DSC_alias_declaration.
 
   // If there are attributes after class name, parse them.
   MaybeParseCXX11Attributes(Attributes);
 
   const PrintingPolicy &Policy = Actions.getASTContext().getPrintingPolicy();
   Sema::TagUseKind TUK;
-  if (DSC == DSC_trailing)
+  if (DSC == DeclSpecContext::DSC_trailing)
     TUK = Sema::TUK_Reference;
   else if (Tok.is(tok::l_brace) ||
            (getLangOpts().CPlusPlus && Tok.is(tok::colon)) ||
@@ -1881,15 +1884,14 @@ void Parser::ParseClassSpecifier(tok::TokenKind TagTokKind,
     stripTypeAttributesOffDeclSpec(attrs, DS, TUK);
 
     // Declaration or definition of a class type
-    TagOrTempResult = Actions.ActOnTag(getCurScope(), TagType, TUK, StartLoc,
-                                       SS, Name, NameLoc, attrs.getList(), AS,
-                                       DS.getModulePrivateSpecLoc(),
-                                       TParams, Owned, IsDependent,
-                                       SourceLocation(), false,
-                                       clang::TypeResult(),
-                                       DSC == DSC_type_specifier,
-                                       DSC == DSC_template_param ||
-                                       DSC == DSC_template_type_arg, &SkipBody);
+    TagOrTempResult = Actions.ActOnTag(
+        getCurScope(), TagType, TUK, StartLoc, SS, Name, NameLoc,
+        attrs.getList(), AS, DS.getModulePrivateSpecLoc(), TParams, Owned,
+        IsDependent, SourceLocation(), false, clang::TypeResult(),
+        DSC == DeclSpecContext::DSC_type_specifier,
+        DSC == DeclSpecContext::DSC_template_param ||
+            DSC == DeclSpecContext::DSC_template_type_arg,
+        &SkipBody);
 
     // If ActOnTag said the type was dependent, try again with the
     // less common call.
@@ -2509,7 +2511,7 @@ Parser::ParseCXXClassMemberDeclaration(AccessSpecifier AS,
     SourceLocation DeclEnd;
     return DeclGroupPtrTy::make(
         DeclGroupRef(ParseTemplateDeclarationOrSpecialization(
-            Declarator::MemberContext, DeclEnd, AS, AccessAttrs)));
+            DeclaratorContext::MemberContext, DeclEnd, AS, AccessAttrs)));
   }
 
   // Handle:  member-declaration ::= '__extension__' member-declaration
@@ -2545,7 +2547,7 @@ Parser::ParseCXXClassMemberDeclaration(AccessSpecifier AS,
     }
     SourceLocation DeclEnd;
     // Otherwise, it must be a using-declaration or an alias-declaration.
-    return ParseUsingDeclaration(Declarator::MemberContext, TemplateInfo,
+    return ParseUsingDeclaration(DeclaratorContext::MemberContext, TemplateInfo,
                                  UsingLoc, DeclEnd, AS);
   }
 
@@ -2559,7 +2561,7 @@ Parser::ParseCXXClassMemberDeclaration(AccessSpecifier AS,
   if (MalformedTypeSpec)
     DS.SetTypeSpecError();
 
-  ParseDeclarationSpecifiers(DS, TemplateInfo, AS, DSC_class,
+  ParseDeclarationSpecifiers(DS, TemplateInfo, AS, DeclSpecContext::DSC_class,
                              &CommonLateParsedAttrs);
 
   // Turn off colon protection that was set for declspec.
@@ -2569,7 +2571,7 @@ Parser::ParseCXXClassMemberDeclaration(AccessSpecifier AS,
   // may get this far before the problem becomes obvious.
   if (DS.hasTagDefinition() &&
       TemplateInfo.Kind == ParsedTemplateInfo::NonTemplate &&
-      DiagnoseMissingSemiAfterTagDefinition(DS, AS, DSC_class,
+      DiagnoseMissingSemiAfterTagDefinition(DS, AS, DeclSpecContext::DSC_class,
                                             &CommonLateParsedAttrs))
     return nullptr;
 
@@ -2593,7 +2595,7 @@ Parser::ParseCXXClassMemberDeclaration(AccessSpecifier AS,
     return Actions.ConvertDeclToDeclGroup(TheDecl);
   }
 
-  ParsingDeclarator DeclaratorInfo(*this, DS, Declarator::MemberContext);
+  ParsingDeclarator DeclaratorInfo(*this, DS, DeclaratorContext::MemberContext);
   VirtSpecifiers VS;
 
   // Hold late-parsed attributes so we can attach a Decl to them later.
@@ -2852,7 +2854,7 @@ Parser::ParseCXXClassMemberDeclaration(AccessSpecifier AS,
       break;
 
     if (Tok.isAtStartOfLine() &&
-        !MightBeDeclarator(Declarator::MemberContext)) {
+        !MightBeDeclarator(DeclaratorContext::MemberContext)) {
       // This comma was followed by a line-break and something which can't be
       // the start of a declarator. The comma was probably a typo for a
       // semicolon.
@@ -3709,7 +3711,7 @@ TypeResult Parser::ParseTrailingReturnType(SourceRange &Range) {
 
   ConsumeToken();
 
-  return ParseTypeName(&Range, Declarator::TrailingReturnContext);
+  return ParseTypeName(&Range, DeclaratorContext::TrailingReturnContext);
 }
 
 /// \brief We have just started parsing the definition of a new class,
diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index bc587628c954d..1b8865edb79aa 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -1000,7 +1000,7 @@ ExprResult Parser::ParseCastExpression(bool isUnaryExpression,
             DS.SetTypeSpecType(TST_typename, ILoc, PrevSpec, DiagID, Typ,
                                Actions.getASTContext().getPrintingPolicy());
             
-            Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+            Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
             TypeResult Ty = Actions.ActOnTypeName(getCurScope(), 
                                                   DeclaratorInfo);
             if (Ty.isInvalid())
@@ -1209,7 +1209,7 @@ ExprResult Parser::ParseCastExpression(bool isUnaryExpression,
                          PrevSpec, DiagID, Type,
                          Actions.getASTContext().getPrintingPolicy());
 
-      Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+      Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
       TypeResult Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
       if (Ty.isInvalid())
         break;
@@ -1824,7 +1824,7 @@ Parser::ParseExprAfterUnaryExprOrTypeTrait(const Token &OpTok,
       if (isTypeIdUnambiguously()) {
         DeclSpec DS(AttrFactory);
         ParseSpecifierQualifierList(DS);
-        Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+        Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
         ParseDeclarator(DeclaratorInfo);
 
         SourceLocation LParenLoc = PP.getLocForEndOfToken(OpTok.getLocation());
@@ -2381,7 +2381,7 @@ Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr,
     // Parse the type declarator.
     DeclSpec DS(AttrFactory);
     ParseSpecifierQualifierList(DS);
-    Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+    Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
     ParseDeclarator(DeclaratorInfo);
     
     // If our type is followed by an identifier and either ':' or ']', then 
@@ -2858,7 +2858,7 @@ void Parser::ParseBlockId(SourceLocation CaretLoc) {
   ParseSpecifierQualifierList(DS);
 
   // Parse the block-declarator.
-  Declarator DeclaratorInfo(DS, Declarator::BlockLiteralContext);
+  Declarator DeclaratorInfo(DS, DeclaratorContext::BlockLiteralContext);
   DeclaratorInfo.setFunctionDefinitionKind(FDK_Definition);
   ParseDeclarator(DeclaratorInfo);
 
@@ -2897,7 +2897,7 @@ ExprResult Parser::ParseBlockLiteralExpression() {
 
   // Parse the return type if present.
   DeclSpec DS(AttrFactory);
-  Declarator ParamInfo(DS, Declarator::BlockLiteralContext);
+  Declarator ParamInfo(DS, DeclaratorContext::BlockLiteralContext);
   ParamInfo.setFunctionDefinitionKind(FDK_Definition);
   // FIXME: Since the return type isn't actually parsed, it can't be used to
   // fill ParamInfo with an initial valid range, so do it manually.
diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index 959cb7a61d3a7..554ab24b02e1c 100644
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -292,8 +292,8 @@ bool Parser::ParseOptionalCXXScopeSpecifier(CXXScopeSpec &SS,
           break;
         }
 
-        if (TemplateName.getKind() != UnqualifiedId::IK_OperatorFunctionId &&
-            TemplateName.getKind() != UnqualifiedId::IK_LiteralOperatorId) {
+        if (TemplateName.getKind() != UnqualifiedIdKind::IK_OperatorFunctionId &&
+            TemplateName.getKind() != UnqualifiedIdKind::IK_LiteralOperatorId) {
           Diag(TemplateName.getSourceRange().getBegin(),
                diag::err_id_after_template_in_nested_name_spec)
             << TemplateName.getSourceRange();
@@ -1090,7 +1090,7 @@ ExprResult Parser::ParseLambdaExpressionAfterIntroducer(
 
   // Parse lambda-declarator[opt].
   DeclSpec DS(AttrFactory);
-  Declarator D(DS, Declarator::LambdaExprContext);
+  Declarator D(DS, DeclaratorContext::LambdaExprContext);
   TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
   Actions.PushLambdaScope();
 
@@ -1353,7 +1353,7 @@ ExprResult Parser::ParseCXXCasts() {
   ParseSpecifierQualifierList(DS);
 
   // Parse the abstract-declarator, if present.
-  Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+  Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
   ParseDeclarator(DeclaratorInfo);
 
   SourceLocation RAngleBracketLoc = Tok.getLocation();
@@ -1660,7 +1660,7 @@ ExprResult Parser::ParseCXXThis() {
 /// In C++1z onwards, the type specifier can also be a template-name.
 ExprResult
 Parser::ParseCXXTypeConstructExpression(const DeclSpec &DS) {
-  Declarator DeclaratorInfo(DS, Declarator::FunctionalCastContext);
+  Declarator DeclaratorInfo(DS, DeclaratorContext::FunctionalCastContext);
   ParsedType TypeRep = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo).get();
 
   assert((Tok.is(tok::l_paren) ||
@@ -1767,8 +1767,9 @@ Sema::ConditionResult Parser::ParseCXXCondition(StmtResult *InitStmt,
                                 : diag::ext_init_statement)
         << (CK == Sema::ConditionKind::Switch);
     SourceLocation DeclStart = Tok.getLocation(), DeclEnd;
-    DeclGroupPtrTy DG = ParseSimpleDeclaration(
-        Declarator::InitStmtContext, DeclEnd, attrs, /*RequireSemi=*/true);
+    DeclGroupPtrTy DG =
+        ParseSimpleDeclaration(DeclaratorContext::InitStmtContext, DeclEnd,
+                               attrs, /*RequireSemi=*/true);
     *InitStmt = Actions.ActOnDeclStmt(DG, DeclStart, DeclEnd);
     return ParseCXXCondition(nullptr, Loc, CK);
   }
@@ -1781,10 +1782,10 @@ Sema::ConditionResult Parser::ParseCXXCondition(StmtResult *InitStmt,
   // type-specifier-seq
   DeclSpec DS(AttrFactory);
   DS.takeAttributesFrom(attrs);
-  ParseSpecifierQualifierList(DS, AS_none, DSC_condition);
+  ParseSpecifierQualifierList(DS, AS_none, DeclSpecContext::DSC_condition);
 
   // declarator
-  Declarator DeclaratorInfo(DS, Declarator::ConditionContext);
+  Declarator DeclaratorInfo(DS, DeclaratorContext::ConditionContext);
   ParseDeclarator(DeclaratorInfo);
 
   // simple-asm-expr[opt]
@@ -1982,7 +1983,7 @@ void Parser::ParseCXXSimpleTypeSpecifier(DeclSpec &DS) {
 ///     type-specifier type-specifier-seq[opt]
 ///
 bool Parser::ParseCXXTypeSpecifierSeq(DeclSpec &DS) {
-  ParseSpecifierQualifierList(DS, AS_none, DSC_type_specifier);
+  ParseSpecifierQualifierList(DS, AS_none, DeclSpecContext::DSC_type_specifier);
   DS.Finish(Actions, Actions.getASTContext().getPrintingPolicy());
   return false;
 }
@@ -2033,9 +2034,9 @@ bool Parser::ParseUnqualifiedIdTemplateId(CXXScopeSpec &SS,
   TemplateTy Template;
   TemplateNameKind TNK = TNK_Non_template;
   switch (Id.getKind()) {
-  case UnqualifiedId::IK_Identifier:
-  case UnqualifiedId::IK_OperatorFunctionId:
-  case UnqualifiedId::IK_LiteralOperatorId:
+  case UnqualifiedIdKind::IK_Identifier:
+  case UnqualifiedIdKind::IK_OperatorFunctionId:
+  case UnqualifiedIdKind::IK_LiteralOperatorId:
     if (AssumeTemplateId) {
       // We defer the injected-class-name checks until we've found whether
       // this template-id is used to form a nested-name-specifier or not.
@@ -2058,11 +2059,11 @@ bool Parser::ParseUnqualifiedIdTemplateId(CXXScopeSpec &SS,
         // parse correctly as a template, so suggest the keyword 'template'
         // before 'getAs' and treat this as a dependent template name.
         std::string Name;
-        if (Id.getKind() == UnqualifiedId::IK_Identifier)
+        if (Id.getKind() == UnqualifiedIdKind::IK_Identifier)
           Name = Id.Identifier->getName();
         else {
           Name = "operator ";
-          if (Id.getKind() == UnqualifiedId::IK_OperatorFunctionId)
+          if (Id.getKind() == UnqualifiedIdKind::IK_OperatorFunctionId)
             Name += getOperatorSpelling(Id.OperatorFunctionId.Operator);
           else
             Name += Id.Identifier->getName();
@@ -2079,7 +2080,7 @@ bool Parser::ParseUnqualifiedIdTemplateId(CXXScopeSpec &SS,
     }
     break;
       
-  case UnqualifiedId::IK_ConstructorName: {
+  case UnqualifiedIdKind::IK_ConstructorName: {
     UnqualifiedId TemplateName;
     bool MemberOfUnknownSpecialization;
     TemplateName.setIdentifier(Name, NameLoc);
@@ -2090,7 +2091,7 @@ bool Parser::ParseUnqualifiedIdTemplateId(CXXScopeSpec &SS,
     break;
   }
       
-  case UnqualifiedId::IK_DestructorName: {
+  case UnqualifiedIdKind::IK_DestructorName: {
     UnqualifiedId TemplateName;
     bool MemberOfUnknownSpecialization;
     TemplateName.setIdentifier(Name, NameLoc);
@@ -2129,18 +2130,20 @@ bool Parser::ParseUnqualifiedIdTemplateId(CXXScopeSpec &SS,
                                true, LAngleLoc, TemplateArgs, RAngleLoc))
     return true;
   
-  if (Id.getKind() == UnqualifiedId::IK_Identifier ||
-      Id.getKind() == UnqualifiedId::IK_OperatorFunctionId ||
-      Id.getKind() == UnqualifiedId::IK_LiteralOperatorId) {
+  if (Id.getKind() == UnqualifiedIdKind::IK_Identifier ||
+      Id.getKind() == UnqualifiedIdKind::IK_OperatorFunctionId ||
+      Id.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId) {
     // Form a parsed representation of the template-id to be stored in the
     // UnqualifiedId.
 
     // FIXME: Store name for literal operator too.
     IdentifierInfo *TemplateII =
-        Id.getKind() == UnqualifiedId::IK_Identifier ? Id.Identifier : nullptr;
-    OverloadedOperatorKind OpKind = Id.getKind() == UnqualifiedId::IK_Identifier
-                                        ? OO_None
-                                        : Id.OperatorFunctionId.Operator;
+        Id.getKind() == UnqualifiedIdKind::IK_Identifier ? Id.Identifier
+                                                         : nullptr;
+    OverloadedOperatorKind OpKind =
+        Id.getKind() == UnqualifiedIdKind::IK_Identifier
+            ? OO_None
+            : Id.OperatorFunctionId.Operator;
 
     TemplateIdAnnotation *TemplateId = TemplateIdAnnotation::Create(
         SS, TemplateKWLoc, Id.StartLocation, TemplateII, OpKind, Template, TNK,
@@ -2162,7 +2165,7 @@ bool Parser::ParseUnqualifiedIdTemplateId(CXXScopeSpec &SS,
   if (Type.isInvalid())
     return true;
   
-  if (Id.getKind() == UnqualifiedId::IK_ConstructorName)
+  if (Id.getKind() == UnqualifiedIdKind::IK_ConstructorName)
     Id.setConstructorName(Type.get(), NameLoc, RAngleLoc);
   else
     Id.setDestructorName(Id.StartLocation, Type.get(), RAngleLoc);
@@ -2395,7 +2398,7 @@ bool Parser::ParseUnqualifiedIdOperator(CXXScopeSpec &SS, bool EnteringContext,
   
   // Parse the conversion-declarator, which is merely a sequence of
   // ptr-operators.
-  Declarator D(DS, Declarator::ConversionIdContext);
+  Declarator D(DS, DeclaratorContext::ConversionIdContext);
   ParseDeclaratorInternal(D, /*DirectDeclParser=*/nullptr);
 
   // Finish up the type.
@@ -2556,8 +2559,8 @@ bool Parser::ParseUnqualifiedId(CXXScopeSpec &SS, bool EnteringContext,
     // 
     //   template-id:
     //     operator-function-id < template-argument-list[opt] >
-    if ((Result.getKind() == UnqualifiedId::IK_OperatorFunctionId ||
-         Result.getKind() == UnqualifiedId::IK_LiteralOperatorId) &&
+    if ((Result.getKind() == UnqualifiedIdKind::IK_OperatorFunctionId ||
+         Result.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId) &&
         (TemplateSpecified || Tok.is(tok::less)))
       return ParseUnqualifiedIdTemplateId(SS, TemplateKWLoc,
                                           nullptr, SourceLocation(),
@@ -2696,7 +2699,7 @@ Parser::ParseCXXNewExpression(bool UseGlobal, SourceLocation Start) {
 
   SourceRange TypeIdParens;
   DeclSpec DS(AttrFactory);
-  Declarator DeclaratorInfo(DS, Declarator::CXXNewContext);
+  Declarator DeclaratorInfo(DS, DeclaratorContext::CXXNewContext);
   if (Tok.is(tok::l_paren)) {
     // If it turns out to be a placement, we change the type location.
     BalancedDelimiterTracker T(*this, tok::l_paren);
@@ -3172,7 +3175,7 @@ Parser::ParseCXXAmbiguousParenExpression(ParenParseOption &ExprType,
   if (ParseAs >= CompoundLiteral) {
     // Parse the type declarator.
     DeclSpec DS(AttrFactory);
-    Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+    Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
     {
       ColonProtectionRAIIObject InnerColonProtection(*this);
       ParseSpecifierQualifierList(DS);
diff --git a/lib/Parse/ParseObjc.cpp b/lib/Parse/ParseObjc.cpp
index fb8624a324b93..688376ca28e69 100644
--- a/lib/Parse/ParseObjc.cpp
+++ b/lib/Parse/ParseObjc.cpp
@@ -1140,14 +1140,14 @@ bool Parser::isTokIdentifier_in() const {
 ///     'null_unspecified'
 ///
 void Parser::ParseObjCTypeQualifierList(ObjCDeclSpec &DS,
-                                        Declarator::TheContext Context) {
-  assert(Context == Declarator::ObjCParameterContext ||
-         Context == Declarator::ObjCResultContext);
+                                        DeclaratorContext Context) {
+  assert(Context == DeclaratorContext::ObjCParameterContext ||
+         Context == DeclaratorContext::ObjCResultContext);
 
   while (1) {
     if (Tok.is(tok::code_completion)) {
       Actions.CodeCompleteObjCPassingType(getCurScope(), DS, 
-                          Context == Declarator::ObjCParameterContext);
+                          Context == DeclaratorContext::ObjCParameterContext);
       return cutOffParsing();
     }
     
@@ -1242,12 +1242,12 @@ static void takeDeclAttributes(ParsedAttributes &attrs,
 ///     '(' objc-type-qualifiers[opt] ')'
 ///
 ParsedType Parser::ParseObjCTypeName(ObjCDeclSpec &DS, 
-                                     Declarator::TheContext context,
+                                     DeclaratorContext context,
                                      ParsedAttributes *paramAttrs) {
-  assert(context == Declarator::ObjCParameterContext ||
-         context == Declarator::ObjCResultContext);
+  assert(context == DeclaratorContext::ObjCParameterContext ||
+         context == DeclaratorContext::ObjCResultContext);
   assert((paramAttrs != nullptr) ==
-         (context == Declarator::ObjCParameterContext));
+         (context == DeclaratorContext::ObjCParameterContext));
 
   assert(Tok.is(tok::l_paren) && "expected (");
 
@@ -1265,9 +1265,9 @@ ParsedType Parser::ParseObjCTypeName(ObjCDeclSpec &DS,
     // Parse an abstract declarator.
     DeclSpec declSpec(AttrFactory);
     declSpec.setObjCQualifiers(&DS);
-    DeclSpecContext dsContext = DSC_normal;
-    if (context == Declarator::ObjCResultContext)
-      dsContext = DSC_objc_method_result;
+    DeclSpecContext dsContext = DeclSpecContext::DSC_normal;
+    if (context == DeclaratorContext::ObjCResultContext)
+      dsContext = DeclSpecContext::DSC_objc_method_result;
     ParseSpecifierQualifierList(declSpec, AS_none, dsContext);
     Declarator declarator(declSpec, context);
     ParseDeclarator(declarator);
@@ -1288,7 +1288,7 @@ ParsedType Parser::ParseObjCTypeName(ObjCDeclSpec &DS,
 
       // If we're parsing a parameter, steal all the decl attributes
       // and add them to the decl spec.
-      if (context == Declarator::ObjCParameterContext)
+      if (context == DeclaratorContext::ObjCParameterContext)
         takeDeclAttributes(*paramAttrs, declarator);
     }
   }
@@ -1352,7 +1352,7 @@ Decl *Parser::ParseObjCMethodDecl(SourceLocation mLoc,
   ParsedType ReturnType;
   ObjCDeclSpec DSRet;
   if (Tok.is(tok::l_paren))
-    ReturnType = ParseObjCTypeName(DSRet, Declarator::ObjCResultContext,
+    ReturnType = ParseObjCTypeName(DSRet, DeclaratorContext::ObjCResultContext,
                                    nullptr);
 
   // If attributes exist before the method, parse them.
@@ -1416,7 +1416,7 @@ Decl *Parser::ParseObjCMethodDecl(SourceLocation mLoc,
     ArgInfo.Type = nullptr;
     if (Tok.is(tok::l_paren)) // Parse the argument type if present.
       ArgInfo.Type = ParseObjCTypeName(ArgInfo.DeclSpec,
-                                       Declarator::ObjCParameterContext,
+                                       DeclaratorContext::ObjCParameterContext,
                                        &paramAttrs);
 
     // If attributes exist before the argument name, parse them.
@@ -1494,7 +1494,7 @@ Decl *Parser::ParseObjCMethodDecl(SourceLocation mLoc,
     DeclSpec DS(AttrFactory);
     ParseDeclarationSpecifiers(DS);
     // Parse the declarator.
-    Declarator ParmDecl(DS, Declarator::PrototypeContext);
+    Declarator ParmDecl(DS, DeclaratorContext::PrototypeContext);
     ParseDeclarator(ParmDecl);
     IdentifierInfo *ParmII = ParmDecl.getIdentifier();
     Decl *Param = Actions.ActOnParamDeclarator(getCurScope(), ParmDecl);
@@ -1703,7 +1703,7 @@ void Parser::parseObjCTypeArgsOrProtocolQualifiers(
                          typeArg, Actions.getASTContext().getPrintingPolicy());
 
       // Form a declarator to turn this into a type.
-      Declarator D(DS, Declarator::TypeNameContext);
+      Declarator D(DS, DeclaratorContext::TypeNameContext);
       TypeResult fullTypeArg = Actions.ActOnTypeName(getCurScope(), D);
       if (fullTypeArg.isUsable()) {
         typeArgs.push_back(fullTypeArg.get());
@@ -2543,7 +2543,7 @@ StmtResult Parser::ParseObjCTryStmt(SourceLocation atLoc) {
         if (Tok.isNot(tok::ellipsis)) {
           DeclSpec DS(AttrFactory);
           ParseDeclarationSpecifiers(DS);
-          Declarator ParmDecl(DS, Declarator::ObjCCatchContext);
+          Declarator ParmDecl(DS, DeclaratorContext::ObjCCatchContext);
           ParseDeclarator(ParmDecl);
 
           // Inform the actions module about the declarator, so it
@@ -2945,7 +2945,7 @@ bool Parser::ParseObjCXXMessageReceiver(bool &IsExpr, void *&TypeOrExpr) {
   // We have a class message. Turn the simple-type-specifier or
   // typename-specifier we parsed into a type and parse the
   // remainder of the class message.
-  Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
+  Declarator DeclaratorInfo(DS, DeclaratorContext::TypeNameContext);
   TypeResult Type = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo);
   if (Type.isInvalid())
     return true;
diff --git a/lib/Parse/ParseOpenMP.cpp b/lib/Parse/ParseOpenMP.cpp
index a67a5bbe0deaa..628c1f134ac5d 100644
--- a/lib/Parse/ParseOpenMP.cpp
+++ b/lib/Parse/ParseOpenMP.cpp
@@ -250,7 +250,8 @@ Parser::ParseOpenMPDeclareReductionDirective(AccessSpecifier AS) {
   do {
     ColonProtectionRAIIObject ColonRAII(*this);
     SourceRange Range;
-    TypeResult TR = ParseTypeName(&Range, Declarator::PrototypeContext, AS);
+    TypeResult TR =
+        ParseTypeName(&Range, DeclaratorContext::PrototypeContext, AS);
     if (TR.isUsable()) {
       auto ReductionType =
           Actions.ActOnOpenMPDeclareReductionType(Range.getBegin(), TR);
diff --git a/lib/Parse/ParseStmt.cpp b/lib/Parse/ParseStmt.cpp
index 3f25610f4471f..09ae9d7f22f6d 100644
--- a/lib/Parse/ParseStmt.cpp
+++ b/lib/Parse/ParseStmt.cpp
@@ -211,7 +211,7 @@ Retry:
          Allowed == ACK_Any) &&
         isDeclarationStatement()) {
       SourceLocation DeclStart = Tok.getLocation(), DeclEnd;
-      DeclGroupPtrTy Decl = ParseDeclaration(Declarator::BlockContext,
+      DeclGroupPtrTy Decl = ParseDeclaration(DeclaratorContext::BlockContext,
                                              DeclEnd, Attrs);
       return Actions.ActOnDeclStmt(Decl, DeclStart, DeclEnd);
     }
@@ -1021,8 +1021,8 @@ StmtResult Parser::ParseCompoundStatementBody(bool isStmtExpr) {
         ExtensionRAIIObject O(Diags);
 
         SourceLocation DeclStart = Tok.getLocation(), DeclEnd;
-        DeclGroupPtrTy Res = ParseDeclaration(Declarator::BlockContext, DeclEnd,
-                                              attrs);
+        DeclGroupPtrTy Res =
+            ParseDeclaration(DeclaratorContext::BlockContext, DeclEnd, attrs);
         R = Actions.ActOnDeclStmt(Res, DeclStart, DeclEnd);
       } else {
         // Otherwise this was a unary __extension__ marker.
@@ -1631,7 +1631,7 @@ StmtResult Parser::ParseForStatement(SourceLocation *TrailingElseLoc) {
 
     SourceLocation DeclStart = Tok.getLocation(), DeclEnd;
     DeclGroupPtrTy DG = ParseSimpleDeclaration(
-        Declarator::ForContext, DeclEnd, attrs, false,
+        DeclaratorContext::ForContext, DeclEnd, attrs, false,
         MightBeForRangeStmt ? &ForRangeInit : nullptr);
     FirstPart = Actions.ActOnDeclStmt(DG, DeclStart, Tok.getLocation());
     if (ForRangeInit.ParsedForRangeDecl()) {
@@ -2181,7 +2181,7 @@ StmtResult Parser::ParseCXXCatchBlock(bool FnCatch) {
     if (ParseCXXTypeSpecifierSeq(DS))
       return StmtError();
 
-    Declarator ExDecl(DS, Declarator::CXXCatchContext);
+    Declarator ExDecl(DS, DeclaratorContext::CXXCatchContext);
     ParseDeclarator(ExDecl);
     ExceptionDecl = Actions.ActOnExceptionDeclarator(getCurScope(), ExDecl);
   } else
diff --git a/lib/Parse/ParseTemplate.cpp b/lib/Parse/ParseTemplate.cpp
index 56a16b9e02711..611c0779b1601 100644
--- a/lib/Parse/ParseTemplate.cpp
+++ b/lib/Parse/ParseTemplate.cpp
@@ -24,7 +24,7 @@ using namespace clang;
 /// \brief Parse a template declaration, explicit instantiation, or
 /// explicit specialization.
 Decl *
-Parser::ParseDeclarationStartingWithTemplate(unsigned Context,
+Parser::ParseDeclarationStartingWithTemplate(DeclaratorContext Context,
                                              SourceLocation &DeclEnd,
                                              AccessSpecifier AS,
                                              AttributeList *AccessAttrs) {
@@ -57,7 +57,7 @@ Parser::ParseDeclarationStartingWithTemplate(unsigned Context,
 ///       explicit-specialization: [ C++ temp.expl.spec]
 ///         'template' '<' '>' declaration
 Decl *
-Parser::ParseTemplateDeclarationOrSpecialization(unsigned Context,
+Parser::ParseTemplateDeclarationOrSpecialization(DeclaratorContext Context,
                                                  SourceLocation &DeclEnd,
                                                  AccessSpecifier AS,
                                                  AttributeList *AccessAttrs) {
@@ -169,7 +169,7 @@ Parser::ParseTemplateDeclarationOrSpecialization(unsigned Context,
 /// \returns the new declaration.
 Decl *
 Parser::ParseSingleDeclarationAfterTemplate(
-                                       unsigned Context,
+                                       DeclaratorContext Context,
                                        const ParsedTemplateInfo &TemplateInfo,
                                        ParsingDeclRAIIObject &DiagsFromTParams,
                                        SourceLocation &DeclEnd,
@@ -186,7 +186,7 @@ Parser::ParseSingleDeclarationAfterTemplate(
     return ParseStaticAssertDeclaration(DeclEnd);
   }
 
-  if (Context == Declarator::MemberContext) {
+  if (Context == DeclaratorContext::MemberContext) {
     // We are parsing a member template.
     ParseCXXClassMemberDeclaration(AS, AccessAttrs, TemplateInfo,
                                    &DiagsFromTParams);
@@ -234,7 +234,7 @@ Parser::ParseSingleDeclarationAfterTemplate(
     DS.takeAttributesFrom(prefixAttrs);
 
   // Parse the declarator.
-  ParsingDeclarator DeclaratorInfo(*this, DS, (Declarator::TheContext)Context);
+  ParsingDeclarator DeclaratorInfo(*this, DS, (DeclaratorContext)Context);
   ParseDeclarator(DeclaratorInfo);
   // Error parsing the declarator?
   if (!DeclaratorInfo.hasName()) {
@@ -255,7 +255,7 @@ Parser::ParseSingleDeclarationAfterTemplate(
     // Function definitions are only allowed at file scope and in C++ classes.
     // The C++ inline method definition case is handled elsewhere, so we only
     // need to handle the file scope definition case.
-    if (Context != Declarator::FileContext) {
+    if (Context != DeclaratorContext::FileContext) {
       Diag(Tok, diag::err_function_definition_not_allowed);
       SkipMalformedDecl();
       return nullptr;
@@ -271,7 +271,8 @@ Parser::ParseSingleDeclarationAfterTemplate(
     }
 
     if (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation) {
-      if (DeclaratorInfo.getName().getKind() != UnqualifiedId::IK_TemplateId) {
+      if (DeclaratorInfo.getName().getKind() !=
+          UnqualifiedIdKind::IK_TemplateId) {
         // If the declarator-id is not a template-id, issue a diagnostic and
         // recover by ignoring the 'template' keyword.
         Diag(Tok, diag::err_template_defn_explicit_instantiation) << 0;
@@ -369,7 +370,7 @@ bool Parser::ParseTemplateParameters(
 ///         template-parameter
 ///         template-parameter-list ',' template-parameter
 bool
-Parser::ParseTemplateParameterList(unsigned Depth,
+Parser::ParseTemplateParameterList(const unsigned Depth,
                              SmallVectorImpl<NamedDecl*> &TemplateParams) {
   while (1) {
     
@@ -546,7 +547,7 @@ NamedDecl *Parser::ParseTypeParameter(unsigned Depth, unsigned Position) {
   ParsedType DefaultArg;
   if (TryConsumeToken(tok::equal, EqualLoc))
     DefaultArg = ParseTypeName(/*Range=*/nullptr,
-                               Declarator::TemplateTypeArgContext).get();
+                               DeclaratorContext::TemplateTypeArgContext).get();
 
   return Actions.ActOnTypeParameter(getCurScope(), TypenameKeyword, EllipsisLoc,
                                     KeyLoc, ParamName, NameLoc, Depth, Position,
@@ -676,10 +677,10 @@ Parser::ParseNonTypeTemplateParameter(unsigned Depth, unsigned Position) {
   // declarators (parts of declarators?) are accepted for parameters.
   DeclSpec DS(AttrFactory);
   ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS_none,
-                             DSC_template_param);
+                             DeclSpecContext::DSC_template_param);
 
   // Parse this as a typename.
-  Declarator ParamDecl(DS, Declarator::TemplateParamContext);
+  Declarator ParamDecl(DS, DeclaratorContext::TemplateParamContext);
   ParseDeclarator(ParamDecl);
   if (DS.getTypeSpecType() == DeclSpec::TST_unspecified) {
     Diag(Tok.getLocation(), diag::err_expected_template_parameter);
@@ -1015,12 +1016,12 @@ bool Parser::AnnotateTemplateIdToken(TemplateTy Template, TemplateNameKind TNK,
     Tok.setKind(tok::annot_template_id);
     
     IdentifierInfo *TemplateII =
-        TemplateName.getKind() == UnqualifiedId::IK_Identifier
+        TemplateName.getKind() == UnqualifiedIdKind::IK_Identifier
             ? TemplateName.Identifier
             : nullptr;
 
     OverloadedOperatorKind OpKind =
-        TemplateName.getKind() == UnqualifiedId::IK_Identifier
+        TemplateName.getKind() == UnqualifiedIdKind::IK_Identifier
             ? OO_None
             : TemplateName.OperatorFunctionId.Operator;
 
@@ -1193,8 +1194,8 @@ ParsedTemplateArgument Parser::ParseTemplateArgument() {
       Actions, Sema::ExpressionEvaluationContext::ConstantEvaluated);
   if (isCXXTypeId(TypeIdAsTemplateArgument)) {
     SourceLocation Loc = Tok.getLocation();
-    TypeResult TypeArg = ParseTypeName(/*Range=*/nullptr,
-                                       Declarator::TemplateTypeArgContext);
+    TypeResult TypeArg = ParseTypeName(
+        /*Range=*/nullptr, DeclaratorContext::TemplateTypeArgContext);
     if (TypeArg.isInvalid())
       return ParsedTemplateArgument();
     
@@ -1297,7 +1298,7 @@ Parser::ParseTemplateArgumentList(TemplateArgList &TemplateArgs) {
 ///         'extern' [opt] 'template' declaration
 ///
 /// Note that the 'extern' is a GNU extension and C++11 feature.
-Decl *Parser::ParseExplicitInstantiation(unsigned Context,
+Decl *Parser::ParseExplicitInstantiation(DeclaratorContext Context,
                                          SourceLocation ExternLoc,
                                          SourceLocation TemplateLoc,
                                          SourceLocation &DeclEnd,
diff --git a/lib/Parse/Parser.cpp b/lib/Parse/Parser.cpp
index 8aa50a2c7f2a5..a6f966eda1b99 100644
--- a/lib/Parse/Parser.cpp
+++ b/lib/Parse/Parser.cpp
@@ -783,7 +783,7 @@ Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
     // A function definition cannot start with any of these keywords.
     {
       SourceLocation DeclEnd;
-      return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
+      return ParseDeclaration(DeclaratorContext::FileContext, DeclEnd, attrs);
     }
 
   case tok::kw_static:
@@ -793,7 +793,7 @@ Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
       Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
         << 0;
       SourceLocation DeclEnd;
-      return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
+      return ParseDeclaration(DeclaratorContext::FileContext, DeclEnd, attrs);
     }
     goto dont_know;
       
@@ -804,7 +804,7 @@ Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
       // Inline namespaces. Allowed as an extension even in C++03.
       if (NextKind == tok::kw_namespace) {
         SourceLocation DeclEnd;
-        return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
+        return ParseDeclaration(DeclaratorContext::FileContext, DeclEnd, attrs);
       }
       
       // Parse (then ignore) 'inline' prior to a template instantiation. This is
@@ -813,7 +813,7 @@ Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
         Diag(ConsumeToken(), diag::warn_static_inline_explicit_inst_ignored)
           << 1;
         SourceLocation DeclEnd;
-        return ParseDeclaration(Declarator::FileContext, DeclEnd, attrs);
+        return ParseDeclaration(DeclaratorContext::FileContext, DeclEnd, attrs);
       }
     }
     goto dont_know;
@@ -828,7 +828,7 @@ Parser::ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
              diag::ext_extern_template) << SourceRange(ExternLoc, TemplateLoc);
       SourceLocation DeclEnd;
       return Actions.ConvertDeclToDeclGroup(
-                  ParseExplicitInstantiation(Declarator::FileContext,
+                  ParseExplicitInstantiation(DeclaratorContext::FileContext,
                                              ExternLoc, TemplateLoc, DeclEnd));
     }
     goto dont_know;
@@ -919,12 +919,13 @@ Parser::ParseDeclOrFunctionDefInternal(ParsedAttributesWithRange &attrs,
                                        AccessSpecifier AS) {
   MaybeParseMicrosoftAttributes(DS.getAttributes());
   // Parse the common declaration-specifiers piece.
-  ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS, DSC_top_level);
+  ParseDeclarationSpecifiers(DS, ParsedTemplateInfo(), AS,
+                             DeclSpecContext::DSC_top_level);
 
   // If we had a free-standing type definition with a missing semicolon, we
   // may get this far before the problem becomes obvious.
-  if (DS.hasTagDefinition() &&
-      DiagnoseMissingSemiAfterTagDefinition(DS, AS, DSC_top_level))
+  if (DS.hasTagDefinition() && DiagnoseMissingSemiAfterTagDefinition(
+                                   DS, AS, DeclSpecContext::DSC_top_level))
     return nullptr;
 
   // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };"
@@ -1004,11 +1005,11 @@ Parser::ParseDeclOrFunctionDefInternal(ParsedAttributesWithRange &attrs,
   if (getLangOpts().CPlusPlus && isTokenStringLiteral() &&
       DS.getStorageClassSpec() == DeclSpec::SCS_extern &&
       DS.getParsedSpecifiers() == DeclSpec::PQ_StorageClassSpecifier) {
-    Decl *TheDecl = ParseLinkage(DS, Declarator::FileContext);
+    Decl *TheDecl = ParseLinkage(DS, DeclaratorContext::FileContext);
     return Actions.ConvertDeclToDeclGroup(TheDecl);
   }
 
-  return ParseDeclGroup(DS, Declarator::FileContext);
+  return ParseDeclGroup(DS, DeclaratorContext::FileContext);
 }
 
 Parser::DeclGroupPtrTy
@@ -1313,7 +1314,7 @@ void Parser::ParseKNRParamDeclarations(Declarator &D) {
     }
 
     // Parse the first declarator attached to this declspec.
-    Declarator ParmDeclarator(DS, Declarator::KNRTypeListContext);
+    Declarator ParmDeclarator(DS, DeclaratorContext::KNRTypeListContext);
     ParseDeclarator(ParmDeclarator);
 
     // Handle the full declarator list.
diff --git a/lib/Sema/DeclSpec.cpp b/lib/Sema/DeclSpec.cpp
index 6fe2dcc9895fb..2fad5a18ba6bc 100644
--- a/lib/Sema/DeclSpec.cpp
+++ b/lib/Sema/DeclSpec.cpp
@@ -30,7 +30,7 @@ using namespace clang;
 
 void UnqualifiedId::setTemplateId(TemplateIdAnnotation *TemplateId) {
   assert(TemplateId && "NULL template-id annotation?");
-  Kind = IK_TemplateId;
+  Kind = UnqualifiedIdKind::IK_TemplateId;
   this->TemplateId = TemplateId;
   StartLocation = TemplateId->TemplateNameLoc;
   EndLocation = TemplateId->RAngleLoc;
@@ -38,7 +38,7 @@ void UnqualifiedId::setTemplateId(TemplateIdAnnotation *TemplateId) {
 
 void UnqualifiedId::setConstructorTemplateId(TemplateIdAnnotation *TemplateId) {
   assert(TemplateId && "NULL template-id annotation?");
-  Kind = IK_ConstructorTemplateId;
+  Kind = UnqualifiedIdKind::IK_ConstructorTemplateId;
   this->TemplateId = TemplateId;
   StartLocation = TemplateId->TemplateNameLoc;
   EndLocation = TemplateId->RAngleLoc;
@@ -387,16 +387,16 @@ bool Declarator::isDeclarationOfFunction() const {
 }
 
 bool Declarator::isStaticMember() {
-  assert(getContext() == MemberContext);
+  assert(getContext() == DeclaratorContext::MemberContext);
   return getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static ||
-         (getName().Kind == UnqualifiedId::IK_OperatorFunctionId &&
+         (getName().Kind == UnqualifiedIdKind::IK_OperatorFunctionId &&
           CXXMethodDecl::isStaticOverloadedOperator(
               getName().OperatorFunctionId.Operator));
 }
 
 bool Declarator::isCtorOrDtor() {
-  return (getName().getKind() == UnqualifiedId::IK_ConstructorName) ||
-         (getName().getKind() == UnqualifiedId::IK_DestructorName);
+  return (getName().getKind() == UnqualifiedIdKind::IK_ConstructorName) ||
+         (getName().getKind() == UnqualifiedIdKind::IK_DestructorName);
 }
 
 bool DeclSpec::hasTagDefinition() const {
@@ -1281,7 +1281,7 @@ bool DeclSpec::isMissingDeclaratorOk() {
 void UnqualifiedId::setOperatorFunctionId(SourceLocation OperatorLoc, 
                                           OverloadedOperatorKind Op,
                                           SourceLocation SymbolLocations[3]) {
-  Kind = IK_OperatorFunctionId;
+  Kind = UnqualifiedIdKind::IK_OperatorFunctionId;
   StartLocation = OperatorLoc;
   EndLocation = OperatorLoc;
   OperatorFunctionId.Operator = Op;
diff --git a/lib/Sema/SemaCodeComplete.cpp b/lib/Sema/SemaCodeComplete.cpp
index 9aed178763dc9..2acc896d53d71 100644
--- a/lib/Sema/SemaCodeComplete.cpp
+++ b/lib/Sema/SemaCodeComplete.cpp
@@ -4171,8 +4171,8 @@ void Sema::CodeCompleteFunctionQualifiers(DeclSpec &DS, Declarator &D,
   AddTypeQualifierResults(DS, Results, LangOpts);
   if (LangOpts.CPlusPlus11) {
     Results.AddResult("noexcept");
-    if (D.getContext() == Declarator::MemberContext && !D.isCtorOrDtor() &&
-        !D.isStaticMember()) {
+    if (D.getContext() == DeclaratorContext::MemberContext &&
+        !D.isCtorOrDtor() && !D.isStaticMember()) {
       if (!VS || !VS->isFinalSpecified())
         Results.AddResult("final");
       if (!VS || !VS->isOverrideSpecified())
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index a1fc725f8df47..743f4bb5e8228 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -4746,7 +4746,7 @@ Decl *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
   }
 
   // Mock up a declarator.
-  Declarator Dc(DS, Declarator::MemberContext);
+  Declarator Dc(DS, DeclaratorContext::MemberContext);
   TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
   assert(TInfo && "couldn't build declarator info for anonymous struct/union");
 
@@ -4843,7 +4843,7 @@ Decl *Sema::BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
   assert(Record && "expected a record!");
 
   // Mock up a declarator.
-  Declarator Dc(DS, Declarator::TypeNameContext);
+  Declarator Dc(DS, DeclaratorContext::TypeNameContext);
   TypeSourceInfo *TInfo = GetTypeForDeclarator(Dc, S);
   assert(TInfo && "couldn't build declarator info for anonymous struct");
 
@@ -4897,13 +4897,13 @@ Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
 
   switch (Name.getKind()) {
 
-  case UnqualifiedId::IK_ImplicitSelfParam:
-  case UnqualifiedId::IK_Identifier:
+  case UnqualifiedIdKind::IK_ImplicitSelfParam:
+  case UnqualifiedIdKind::IK_Identifier:
     NameInfo.setName(Name.Identifier);
     NameInfo.setLoc(Name.StartLocation);
     return NameInfo;
 
-  case UnqualifiedId::IK_DeductionGuideName: {
+  case UnqualifiedIdKind::IK_DeductionGuideName: {
     // C++ [temp.deduct.guide]p3:
     //   The simple-template-id shall name a class template specialization.
     //   The template-name shall be the same identifier as the template-name
@@ -4931,7 +4931,7 @@ Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
     return NameInfo;
   }
 
-  case UnqualifiedId::IK_OperatorFunctionId:
+  case UnqualifiedIdKind::IK_OperatorFunctionId:
     NameInfo.setName(Context.DeclarationNames.getCXXOperatorName(
                                            Name.OperatorFunctionId.Operator));
     NameInfo.setLoc(Name.StartLocation);
@@ -4941,14 +4941,14 @@ Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
       = Name.EndLocation.getRawEncoding();
     return NameInfo;
 
-  case UnqualifiedId::IK_LiteralOperatorId:
+  case UnqualifiedIdKind::IK_LiteralOperatorId:
     NameInfo.setName(Context.DeclarationNames.getCXXLiteralOperatorName(
                                                            Name.Identifier));
     NameInfo.setLoc(Name.StartLocation);
     NameInfo.setCXXLiteralOperatorNameLoc(Name.EndLocation);
     return NameInfo;
 
-  case UnqualifiedId::IK_ConversionFunctionId: {
+  case UnqualifiedIdKind::IK_ConversionFunctionId: {
     TypeSourceInfo *TInfo;
     QualType Ty = GetTypeFromParser(Name.ConversionFunctionId, &TInfo);
     if (Ty.isNull())
@@ -4960,7 +4960,7 @@ Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
     return NameInfo;
   }
 
-  case UnqualifiedId::IK_ConstructorName: {
+  case UnqualifiedIdKind::IK_ConstructorName: {
     TypeSourceInfo *TInfo;
     QualType Ty = GetTypeFromParser(Name.ConstructorName, &TInfo);
     if (Ty.isNull())
@@ -4972,7 +4972,7 @@ Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
     return NameInfo;
   }
 
-  case UnqualifiedId::IK_ConstructorTemplateId: {
+  case UnqualifiedIdKind::IK_ConstructorTemplateId: {
     // In well-formed code, we can only have a constructor
     // template-id that refers to the current context, so go there
     // to find the actual type being constructed.
@@ -4995,7 +4995,7 @@ Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
     return NameInfo;
   }
 
-  case UnqualifiedId::IK_DestructorName: {
+  case UnqualifiedIdKind::IK_DestructorName: {
     TypeSourceInfo *TInfo;
     QualType Ty = GetTypeFromParser(Name.DestructorName, &TInfo);
     if (Ty.isNull())
@@ -5007,7 +5007,7 @@ Sema::GetNameFromUnqualifiedId(const UnqualifiedId &Name) {
     return NameInfo;
   }
 
-  case UnqualifiedId::IK_TemplateId: {
+  case UnqualifiedIdKind::IK_TemplateId: {
     TemplateName TName = Name.TemplateId->Template.get();
     SourceLocation TNameLoc = Name.TemplateId->TemplateNameLoc;
     return Context.getNameForTemplate(TName, TNameLoc);
@@ -5670,8 +5670,8 @@ Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
     Diag(D.getDeclSpec().getConstexprSpecLoc(), diag::err_invalid_constexpr)
       << 1;
 
-  if (D.getName().Kind != UnqualifiedId::IK_Identifier) {
-    if (D.getName().Kind == UnqualifiedId::IK_DeductionGuideName)
+  if (D.getName().Kind != UnqualifiedIdKind::IK_Identifier) {
+    if (D.getName().Kind == UnqualifiedIdKind::IK_DeductionGuideName)
       Diag(D.getName().StartLocation,
            diag::err_deduction_guide_invalid_specifier)
           << "typedef";
@@ -6425,7 +6425,7 @@ NamedDecl *Sema::ActOnVariableDeclarator(
     TemplateParams = MatchTemplateParametersToScopeSpecifier(
         D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
         D.getCXXScopeSpec(),
-        D.getName().getKind() == UnqualifiedId::IK_TemplateId
+        D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId
             ? D.getName().TemplateId
             : nullptr,
         TemplateParamLists,
@@ -6433,7 +6433,7 @@ NamedDecl *Sema::ActOnVariableDeclarator(
 
     if (TemplateParams) {
       if (!TemplateParams->size() &&
-          D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
+          D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId) {
         // There is an extraneous 'template<>' for this variable. Complain
         // about it, but allow the declaration of the variable.
         Diag(TemplateParams->getTemplateLoc(),
@@ -6443,7 +6443,7 @@ NamedDecl *Sema::ActOnVariableDeclarator(
                          TemplateParams->getRAngleLoc());
         TemplateParams = nullptr;
       } else {
-        if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
+        if (D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId) {
           // This is an explicit specialization or a partial specialization.
           // FIXME: Check that we can declare a specialization here.
           IsVariableTemplateSpecialization = true;
@@ -6464,9 +6464,9 @@ NamedDecl *Sema::ActOnVariableDeclarator(
         }
       }
     } else {
-      assert(
-          (Invalid || D.getName().getKind() != UnqualifiedId::IK_TemplateId) &&
-          "should have a 'template<>' for this decl");
+      assert((Invalid ||
+              D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId) &&
+             "should have a 'template<>' for this decl");
     }
 
     if (IsVariableTemplateSpecialization) {
@@ -8261,7 +8261,7 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
             MatchTemplateParametersToScopeSpecifier(
                 D.getDeclSpec().getLocStart(), D.getIdentifierLoc(),
                 D.getCXXScopeSpec(),
-                D.getName().getKind() == UnqualifiedId::IK_TemplateId
+                D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId
                     ? D.getName().TemplateId
                     : nullptr,
                 TemplateParamLists, isFriend, isMemberSpecialization,
@@ -8318,7 +8318,7 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
           // and clearly the user wants a template specialization.  So
           // we need to insert '<>' after the name.
           SourceLocation InsertLoc;
-          if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
+          if (D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId) {
             InsertLoc = D.getName().getSourceRange().getEnd();
             InsertLoc = getLocForEndOfToken(InsertLoc);
           }
@@ -8719,7 +8719,7 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
 
     // If the declarator is a template-id, translate the parser's template
     // argument list into our AST format.
-    if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
+    if (D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId) {
       TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
       TemplateArgs.setLAngleLoc(TemplateId->LAngleLoc);
       TemplateArgs.setRAngleLoc(TemplateId->RAngleLoc);
@@ -10893,7 +10893,7 @@ Sema::ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
   DS.SetTypeSpecType(DeclSpec::TST_auto, IdentLoc, PrevSpec, DiagID,
                      getPrintingPolicy());
 
-  Declarator D(DS, Declarator::ForContext);
+  Declarator D(DS, DeclaratorContext::ForContext);
   D.SetIdentifier(Ident, IdentLoc);
   D.takeAttributes(Attrs, AttrEnd);
 
@@ -11809,7 +11809,7 @@ void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
         // Use the identifier location for the type source range.
         DS.SetRangeStart(FTI.Params[i].IdentLoc);
         DS.SetRangeEnd(FTI.Params[i].IdentLoc);
-        Declarator ParamD(DS, Declarator::KNRTypeListContext);
+        Declarator ParamD(DS, DeclaratorContext::KNRTypeListContext);
         ParamD.SetIdentifier(FTI.Params[i].Ident, FTI.Params[i].IdentLoc);
         FTI.Params[i].Param = ActOnParamDeclarator(S, ParamD);
       }
@@ -12574,7 +12574,7 @@ NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc,
   (void)Error; // Silence warning.
   assert(!Error && "Error setting up implicit decl!");
   SourceLocation NoLoc;
-  Declarator D(DS, Declarator::BlockContext);
+  Declarator D(DS, DeclaratorContext::BlockContext);
   D.AddTypeInfo(DeclaratorChunk::getFunction(/*HasProto=*/false,
                                              /*IsAmbiguous=*/false,
                                              /*LParenLoc=*/NoLoc,
diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index aa26b37f444d9..5e24649c71bea 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -712,7 +712,7 @@ Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
   Diag(Decomp.getLSquareLoc(),
        !getLangOpts().CPlusPlus17
            ? diag::ext_decomp_decl
-           : D.getContext() == Declarator::ConditionContext
+           : D.getContext() == DeclaratorContext::ConditionContext
                  ? diag::ext_decomp_decl_cond
                  : diag::warn_cxx14_compat_decomp_decl)
       << Decomp.getSourceRange();
@@ -8986,15 +8986,15 @@ Decl *Sema::ActOnUsingDeclaration(Scope *S,
   }
 
   switch (Name.getKind()) {
-  case UnqualifiedId::IK_ImplicitSelfParam:
-  case UnqualifiedId::IK_Identifier:
-  case UnqualifiedId::IK_OperatorFunctionId:
-  case UnqualifiedId::IK_LiteralOperatorId:
-  case UnqualifiedId::IK_ConversionFunctionId:
+  case UnqualifiedIdKind::IK_ImplicitSelfParam:
+  case UnqualifiedIdKind::IK_Identifier:
+  case UnqualifiedIdKind::IK_OperatorFunctionId:
+  case UnqualifiedIdKind::IK_LiteralOperatorId:
+  case UnqualifiedIdKind::IK_ConversionFunctionId:
     break;
 
-  case UnqualifiedId::IK_ConstructorName:
-  case UnqualifiedId::IK_ConstructorTemplateId:
+  case UnqualifiedIdKind::IK_ConstructorName:
+  case UnqualifiedIdKind::IK_ConstructorTemplateId:
     // C++11 inheriting constructors.
     Diag(Name.getLocStart(),
          getLangOpts().CPlusPlus11 ?
@@ -9006,17 +9006,17 @@ Decl *Sema::ActOnUsingDeclaration(Scope *S,
 
     return nullptr;
 
-  case UnqualifiedId::IK_DestructorName:
+  case UnqualifiedIdKind::IK_DestructorName:
     Diag(Name.getLocStart(), diag::err_using_decl_destructor)
       << SS.getRange();
     return nullptr;
 
-  case UnqualifiedId::IK_TemplateId:
+  case UnqualifiedIdKind::IK_TemplateId:
     Diag(Name.getLocStart(), diag::err_using_decl_template_id)
       << SourceRange(Name.TemplateId->LAngleLoc, Name.TemplateId->RAngleLoc);
     return nullptr;
 
-  case UnqualifiedId::IK_DeductionGuideName:
+  case UnqualifiedIdKind::IK_DeductionGuideName:
     llvm_unreachable("cannot parse qualified deduction guide name");
   }
 
@@ -10040,7 +10040,7 @@ Decl *Sema::ActOnAliasDeclaration(Scope *S,
     Previous.clear();
   }
 
-  assert(Name.Kind == UnqualifiedId::IK_Identifier &&
+  assert(Name.Kind == UnqualifiedIdKind::IK_Identifier &&
          "name in alias declaration must be an identifier");
   TypeAliasDecl *NewTD = TypeAliasDecl::Create(Context, CurContext, UsingLoc,
                                                Name.StartLocation,
@@ -12215,30 +12215,27 @@ void Sema::DefineImplicitLambdaToFunctionPointerConversion(
                             SourceLocation CurrentLocation,
                             CXXConversionDecl *Conv) {
   SynthesizedFunctionScope Scope(*this, Conv);
+  assert(!Conv->getReturnType()->isUndeducedType());
 
   CXXRecordDecl *Lambda = Conv->getParent();
-  CXXMethodDecl *CallOp = Lambda->getLambdaCallOperator();
-  // If we are defining a specialization of a conversion to function-ptr
-  // cache the deduced template arguments for this specialization
-  // so that we can use them to retrieve the corresponding call-operator
-  // and static-invoker.
-  const TemplateArgumentList *DeducedTemplateArgs = nullptr;
-
-  // Retrieve the corresponding call-operator specialization.
-  if (Lambda->isGenericLambda()) {
-    assert(Conv->isFunctionTemplateSpecialization());
-    FunctionTemplateDecl *CallOpTemplate =
-        CallOp->getDescribedFunctionTemplate();
-    DeducedTemplateArgs = Conv->getTemplateSpecializationArgs();
-    void *InsertPos = nullptr;
-    FunctionDecl *CallOpSpec = CallOpTemplate->findSpecialization(
-                                                DeducedTemplateArgs->asArray(),
-                                                InsertPos);
-    assert(CallOpSpec &&
-          "Conversion operator must have a corresponding call operator");
-    CallOp = cast<CXXMethodDecl>(CallOpSpec);
+  FunctionDecl *CallOp = Lambda->getLambdaCallOperator();
+  FunctionDecl *Invoker = Lambda->getLambdaStaticInvoker();
+
+  if (auto *TemplateArgs = Conv->getTemplateSpecializationArgs()) {
+    CallOp = InstantiateFunctionDeclaration(
+        CallOp->getDescribedFunctionTemplate(), TemplateArgs, CurrentLocation);
+    if (!CallOp)
+      return;
+
+    Invoker = InstantiateFunctionDeclaration(
+        Invoker->getDescribedFunctionTemplate(), TemplateArgs, CurrentLocation);
+    if (!Invoker)
+      return;
   }
 
+  if (CallOp->isInvalidDecl())
+    return;
+
   // Mark the call operator referenced (and add to pending instantiations
   // if necessary).
   // For both the conversion and static-invoker template specializations
@@ -12246,39 +12243,24 @@ void Sema::DefineImplicitLambdaToFunctionPointerConversion(
   // to the PendingInstantiations.
   MarkFunctionReferenced(CurrentLocation, CallOp);
 
-  // Retrieve the static invoker...
-  CXXMethodDecl *Invoker = Lambda->getLambdaStaticInvoker();
-  // ... and get the corresponding specialization for a generic lambda.
-  if (Lambda->isGenericLambda()) {
-    assert(DeducedTemplateArgs &&
-      "Must have deduced template arguments from Conversion Operator");
-    FunctionTemplateDecl *InvokeTemplate =
-                          Invoker->getDescribedFunctionTemplate();
-    void *InsertPos = nullptr;
-    FunctionDecl *InvokeSpec = InvokeTemplate->findSpecialization(
-                                                DeducedTemplateArgs->asArray(),
-                                                InsertPos);
-    assert(InvokeSpec &&
-      "Must have a corresponding static invoker specialization");
-    Invoker = cast<CXXMethodDecl>(InvokeSpec);
-  }
+  // Fill in the __invoke function with a dummy implementation. IR generation
+  // will fill in the actual details. Update its type in case it contained
+  // an 'auto'.
+  Invoker->markUsed(Context);
+  Invoker->setReferenced();
+  Invoker->setType(Conv->getReturnType()->getPointeeType());
+  Invoker->setBody(new (Context) CompoundStmt(Conv->getLocation()));
+
   // Construct the body of the conversion function { return __invoke; }.
   Expr *FunctionRef = BuildDeclRefExpr(Invoker, Invoker->getType(),
-                                        VK_LValue, Conv->getLocation()).get();
+                                       VK_LValue, Conv->getLocation()).get();
   assert(FunctionRef && "Can't refer to __invoke function?");
   Stmt *Return = BuildReturnStmt(Conv->getLocation(), FunctionRef).get();
   Conv->setBody(CompoundStmt::Create(Context, Return, Conv->getLocation(),
                                      Conv->getLocation()));
-
   Conv->markUsed(Context);
   Conv->setReferenced();
 
-  // Fill in the __invoke function with a dummy implementation. IR generation
-  // will fill in the actual details.
-  Invoker->markUsed(Context);
-  Invoker->setReferenced();
-  Invoker->setBody(new (Context) CompoundStmt(Conv->getLocation()));
-
   if (ASTMutationListener *L = getASTMutationListener()) {
     L->CompletedImplicitDefinition(Conv);
     L->CompletedImplicitDefinition(Invoker);
@@ -13625,7 +13607,7 @@ Decl *Sema::ActOnFriendTypeDecl(Scope *S, const DeclSpec &DS,
   // Try to convert the decl specifier to a type.  This works for
   // friend templates because ActOnTag never produces a ClassTemplateDecl
   // for a TUK_Friend.
-  Declarator TheDeclarator(DS, Declarator::MemberContext);
+  Declarator TheDeclarator(DS, DeclaratorContext::MemberContext);
   TypeSourceInfo *TSI = GetTypeForDeclarator(TheDeclarator, S);
   QualType T = TSI->getType();
   if (TheDeclarator.isInvalidType())
@@ -13799,7 +13781,8 @@ NamedDecl *Sema::ActOnFriendFunctionDecl(Scope *S, Declarator &D,
     //   elaborated-type-specifier, the lookup to determine whether
     //   the entity has been previously declared shall not consider
     //   any scopes outside the innermost enclosing namespace.
-    bool isTemplateId = D.getName().getKind() == UnqualifiedId::IK_TemplateId;
+    bool isTemplateId =
+        D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId;
 
     // Find the appropriate context according to the above.
     DC = CurContext;
@@ -13910,24 +13893,24 @@ NamedDecl *Sema::ActOnFriendFunctionDecl(Scope *S, Declarator &D,
   if (!DC->isRecord()) {
     int DiagArg = -1;
     switch (D.getName().getKind()) {
-    case UnqualifiedId::IK_ConstructorTemplateId:
-    case UnqualifiedId::IK_ConstructorName:
+    case UnqualifiedIdKind::IK_ConstructorTemplateId:
+    case UnqualifiedIdKind::IK_ConstructorName:
       DiagArg = 0;
       break;
-    case UnqualifiedId::IK_DestructorName:
+    case UnqualifiedIdKind::IK_DestructorName:
       DiagArg = 1;
       break;
-    case UnqualifiedId::IK_ConversionFunctionId:
+    case UnqualifiedIdKind::IK_ConversionFunctionId:
       DiagArg = 2;
       break;
-    case UnqualifiedId::IK_DeductionGuideName:
+    case UnqualifiedIdKind::IK_DeductionGuideName:
       DiagArg = 3;
       break;
-    case UnqualifiedId::IK_Identifier:
-    case UnqualifiedId::IK_ImplicitSelfParam:
-    case UnqualifiedId::IK_LiteralOperatorId:
-    case UnqualifiedId::IK_OperatorFunctionId:
-    case UnqualifiedId::IK_TemplateId:
+    case UnqualifiedIdKind::IK_Identifier:
+    case UnqualifiedIdKind::IK_ImplicitSelfParam:
+    case UnqualifiedIdKind::IK_LiteralOperatorId:
+    case UnqualifiedIdKind::IK_OperatorFunctionId:
+    case UnqualifiedIdKind::IK_TemplateId:
       break;
     }
     // This implies that it has to be an operator or function.
diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index abbdc9574b8ce..ff3c07e938a80 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -1538,7 +1538,7 @@ void Sema::actOnObjCTypeArgsOrProtocolQualifiers(
     DS.SetRangeEnd(loc);
 
     // Form the declarator.
-    Declarator D(DS, Declarator::TypeNameContext);
+    Declarator D(DS, DeclaratorContext::TypeNameContext);
 
     // If we have a typedef of an Objective-C class type that is missing a '*',
     // add the '*'.
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 4746355e98003..7e01b058ab2d9 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1711,7 +1711,7 @@ Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id,
                              TemplateArgumentListInfo &Buffer,
                              DeclarationNameInfo &NameInfo,
                              const TemplateArgumentListInfo *&TemplateArgs) {
-  if (Id.getKind() == UnqualifiedId::IK_TemplateId) {
+  if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId) {
     Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc);
     Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc);
 
@@ -2070,9 +2070,10 @@ Sema::ActOnIdExpression(Scope *S, CXXScopeSpec &SS,
                                       IsAddressOfOperand, TemplateArgs);
 
   // Perform the required lookup.
-  LookupResult R(*this, NameInfo, 
-                 (Id.getKind() == UnqualifiedId::IK_ImplicitSelfParam) 
-                  ? LookupObjCImplicitSelfParam : LookupOrdinaryName);
+  LookupResult R(*this, NameInfo,
+                 (Id.getKind() == UnqualifiedIdKind::IK_ImplicitSelfParam)
+                     ? LookupObjCImplicitSelfParam
+                     : LookupOrdinaryName);
   if (TemplateArgs) {
     // Lookup the template name again to correctly establish the context in
     // which it was found. This is really unfortunate as we already did the
@@ -2243,7 +2244,7 @@ Sema::ActOnIdExpression(Scope *S, CXXScopeSpec &SS,
     // In C++1y, if this is a variable template id, then check it
     // in BuildTemplateIdExpr().
     // The single lookup result must be a variable template declaration.
-    if (Id.getKind() == UnqualifiedId::IK_TemplateId && Id.TemplateId &&
+    if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId && Id.TemplateId &&
         Id.TemplateId->Kind == TNK_Var_template) {
       assert(R.getAsSingle<VarTemplateDecl>() &&
              "There should only be one declaration found.");
@@ -2401,7 +2402,7 @@ Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S,
       IdentifierInfo &II = Context.Idents.get("self");
       UnqualifiedId SelfName;
       SelfName.setIdentifier(&II, SourceLocation());
-      SelfName.setKind(UnqualifiedId::IK_ImplicitSelfParam);
+      SelfName.setKind(UnqualifiedIdKind::IK_ImplicitSelfParam);
       CXXScopeSpec SelfScopeSpec;
       SourceLocation TemplateKWLoc;
       ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, TemplateKWLoc,
@@ -12834,7 +12835,7 @@ void Sema::ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo,
                                Scope *CurScope) {
   assert(ParamInfo.getIdentifier() == nullptr &&
          "block-id should have no identifier!");
-  assert(ParamInfo.getContext() == Declarator::BlockLiteralContext);
+  assert(ParamInfo.getContext() == DeclaratorContext::BlockLiteralContext);
   BlockScopeInfo *CurBlock = getCurBlock();
 
   TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope);
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index cff9fbbf491b2..89055aecd4b6d 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -356,7 +356,7 @@ ParsedType Sema::getDestructorTypeForDecltype(const DeclSpec &DS,
 
 bool Sema::checkLiteralOperatorId(const CXXScopeSpec &SS,
                                   const UnqualifiedId &Name) {
-  assert(Name.getKind() == UnqualifiedId::IK_LiteralOperatorId);
+  assert(Name.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId);
 
   if (!SS.isValid())
     return false;
@@ -6716,11 +6716,11 @@ ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
                                            SourceLocation CCLoc,
                                            SourceLocation TildeLoc,
                                            UnqualifiedId &SecondTypeName) {
-  assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
-          FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
+  assert((FirstTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
+          FirstTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) &&
          "Invalid first type name in pseudo-destructor");
-  assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
-          SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
+  assert((SecondTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
+          SecondTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) &&
          "Invalid second type name in pseudo-destructor");
 
   QualType ObjectType;
@@ -6742,7 +6742,7 @@ ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
   QualType DestructedType;
   TypeSourceInfo *DestructedTypeInfo = nullptr;
   PseudoDestructorTypeStorage Destructed;
-  if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) {
+  if (SecondTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) {
     ParsedType T = getTypeName(*SecondTypeName.Identifier,
                                SecondTypeName.StartLocation,
                                S, &SS, true, false, ObjectTypePtrForLookup,
@@ -6800,9 +6800,9 @@ ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
   // Convert the name of the scope type (the type prior to '::') into a type.
   TypeSourceInfo *ScopeTypeInfo = nullptr;
   QualType ScopeType;
-  if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
+  if (FirstTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
       FirstTypeName.Identifier) {
-    if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) {
+    if (FirstTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) {
       ParsedType T = getTypeName(*FirstTypeName.Identifier,
                                  FirstTypeName.StartLocation,
                                  S, &SS, true, false, ObjectTypePtrForLookup,
diff --git a/lib/Sema/SemaExprMember.cpp b/lib/Sema/SemaExprMember.cpp
index dd516ea3b4284..f57f79e62efe0 100644
--- a/lib/Sema/SemaExprMember.cpp
+++ b/lib/Sema/SemaExprMember.cpp
@@ -1707,7 +1707,7 @@ ExprResult Sema::ActOnMemberAccessExpr(Scope *S, Expr *Base,
 
   // Warn about the explicit constructor calls Microsoft extension.
   if (getLangOpts().MicrosoftExt &&
-      Id.getKind() == UnqualifiedId::IK_ConstructorName)
+      Id.getKind() == UnqualifiedIdKind::IK_ConstructorName)
     Diag(Id.getSourceRange().getBegin(),
          diag::ext_ms_explicit_constructor_call);
 
diff --git a/lib/Sema/SemaLambda.cpp b/lib/Sema/SemaLambda.cpp
index cbfc330ca60b2..19d2de719728d 100644
--- a/lib/Sema/SemaLambda.cpp
+++ b/lib/Sema/SemaLambda.cpp
@@ -1167,6 +1167,24 @@ void Sema::ActOnLambdaError(SourceLocation StartLoc, Scope *CurScope,
   PopFunctionScopeInfo();
 }
 
+QualType Sema::getLambdaConversionFunctionResultType(
+    const FunctionProtoType *CallOpProto) {
+  // The function type inside the pointer type is the same as the call
+  // operator with some tweaks. The calling convention is the default free
+  // function convention, and the type qualifications are lost.
+  const FunctionProtoType::ExtProtoInfo CallOpExtInfo = 
+      CallOpProto->getExtProtoInfo();   
+  FunctionProtoType::ExtProtoInfo InvokerExtInfo = CallOpExtInfo;
+  CallingConv CC = Context.getDefaultCallingConvention(
+      CallOpProto->isVariadic(), /*IsCXXMethod=*/false);
+  InvokerExtInfo.ExtInfo = InvokerExtInfo.ExtInfo.withCallingConv(CC);
+  InvokerExtInfo.TypeQuals = 0;
+  assert(InvokerExtInfo.RefQualifier == RQ_None && 
+      "Lambda's call operator should not have a reference qualifier");
+  return Context.getFunctionType(CallOpProto->getReturnType(),
+                                 CallOpProto->getParamTypes(), InvokerExtInfo);
+}
+
 /// \brief Add a lambda's conversion to function pointer, as described in
 /// C++11 [expr.prim.lambda]p6.
 static void addFunctionPointerConversion(Sema &S,
@@ -1182,25 +1200,9 @@ static void addFunctionPointerConversion(Sema &S,
     return;
 
   // Add the conversion to function pointer.
-  const FunctionProtoType *CallOpProto = 
-      CallOperator->getType()->getAs<FunctionProtoType>();
-  const FunctionProtoType::ExtProtoInfo CallOpExtInfo = 
-      CallOpProto->getExtProtoInfo();   
-  QualType PtrToFunctionTy;
-  QualType InvokerFunctionTy;
-  {
-    FunctionProtoType::ExtProtoInfo InvokerExtInfo = CallOpExtInfo;
-    CallingConv CC = S.Context.getDefaultCallingConvention(
-        CallOpProto->isVariadic(), /*IsCXXMethod=*/false);
-    InvokerExtInfo.ExtInfo = InvokerExtInfo.ExtInfo.withCallingConv(CC);
-    InvokerExtInfo.TypeQuals = 0;
-    assert(InvokerExtInfo.RefQualifier == RQ_None && 
-        "Lambda's call operator should not have a reference qualifier");
-    InvokerFunctionTy =
-        S.Context.getFunctionType(CallOpProto->getReturnType(),
-                                  CallOpProto->getParamTypes(), InvokerExtInfo);
-    PtrToFunctionTy = S.Context.getPointerType(InvokerFunctionTy);
-  }
+  QualType InvokerFunctionTy = S.getLambdaConversionFunctionResultType(
+      CallOperator->getType()->castAs<FunctionProtoType>());
+  QualType PtrToFunctionTy = S.Context.getPointerType(InvokerFunctionTy);
 
   // Create the type of the conversion function.
   FunctionProtoType::ExtProtoInfo ConvExtInfo(
@@ -1357,19 +1359,8 @@ static void addBlockPointerConversion(Sema &S,
                                       SourceRange IntroducerRange,
                                       CXXRecordDecl *Class,
                                       CXXMethodDecl *CallOperator) {
-  const FunctionProtoType *Proto =
-      CallOperator->getType()->getAs<FunctionProtoType>();
-
-  // The function type inside the block pointer type is the same as the call
-  // operator with some tweaks. The calling convention is the default free
-  // function convention, and the type qualifications are lost.
-  FunctionProtoType::ExtProtoInfo BlockEPI = Proto->getExtProtoInfo();
-  BlockEPI.ExtInfo =
-      BlockEPI.ExtInfo.withCallingConv(S.Context.getDefaultCallingConvention(
-          Proto->isVariadic(), /*IsCXXMethod=*/false));
-  BlockEPI.TypeQuals = 0;
-  QualType FunctionTy = S.Context.getFunctionType(
-      Proto->getReturnType(), Proto->getParamTypes(), BlockEPI);
+  QualType FunctionTy = S.getLambdaConversionFunctionResultType(
+      CallOperator->getType()->castAs<FunctionProtoType>());
   QualType BlockPtrTy = S.Context.getBlockPointerType(FunctionTy);
 
   FunctionProtoType::ExtProtoInfo ConversionEPI(
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 2144845f4dd36..f2b1963df1ed2 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -5145,7 +5145,8 @@ Sema::PerformObjectArgumentInitialization(Expr *From,
       *this, From->getLocStart(), From->getType(), FromClassification, Method,
       Method->getParent());
   if (ICS.isBad()) {
-    if (ICS.Bad.Kind == BadConversionSequence::bad_qualifiers) {
+    switch (ICS.Bad.Kind) {
+    case BadConversionSequence::bad_qualifiers: {
       Qualifiers FromQs = FromRecordType.getQualifiers();
       Qualifiers ToQs = DestType.getQualifiers();
       unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers();
@@ -5158,10 +5159,28 @@ Sema::PerformObjectArgumentInitialization(Expr *From,
           << Method->getDeclName();
         return ExprError();
       }
+      break;
+    }
+
+    case BadConversionSequence::lvalue_ref_to_rvalue:
+    case BadConversionSequence::rvalue_ref_to_lvalue: {
+      bool IsRValueQualified =
+        Method->getRefQualifier() == RefQualifierKind::RQ_RValue;
+      Diag(From->getLocStart(), diag::err_member_function_call_bad_ref)
+        << Method->getDeclName() << FromClassification.isRValue()
+        << IsRValueQualified;
+      Diag(Method->getLocation(), diag::note_previous_decl)
+        << Method->getDeclName();
+      return ExprError();
+    }
+
+    case BadConversionSequence::no_conversion:
+    case BadConversionSequence::unrelated_class:
+      break;
     }
 
     return Diag(From->getLocStart(),
-                diag::err_implicit_object_parameter_init)
+                diag::err_member_function_call_bad_type)
        << ImplicitParamRecordType << FromRecordType << From->getSourceRange();
   }
 
@@ -11309,9 +11328,6 @@ Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl,
   return Matched;
 }
 
-
-
-
 // Resolve and fix an overloaded expression that can be resolved
 // because it identifies a single function template specialization.
 //
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
index 4474d62949a24..1ebc36716a881 100644
--- a/lib/Sema/SemaStmt.cpp
+++ b/lib/Sema/SemaStmt.cpp
@@ -14,6 +14,7 @@
 #include "clang/Sema/SemaInternal.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/ASTDiagnostic.h"
+#include "clang/AST/ASTLambda.h"
 #include "clang/AST/CharUnits.h"
 #include "clang/AST/CXXInheritance.h"
 #include "clang/AST/DeclObjC.h"
@@ -3228,6 +3229,12 @@ bool Sema::DeduceFunctionTypeFromReturnExpr(FunctionDecl *FD,
                                             SourceLocation ReturnLoc,
                                             Expr *&RetExpr,
                                             AutoType *AT) {
+  // If this is the conversion function for a lambda, we choose to deduce it
+  // type from the corresponding call operator, not from the synthesized return
+  // statement within it. See Sema::DeduceReturnType.
+  if (isLambdaConversionOperator(FD))
+    return false;
+
   TypeLoc OrigResultType = getReturnTypeLoc(FD);
   QualType Deduced;
 
diff --git a/lib/Sema/SemaTemplate.cpp b/lib/Sema/SemaTemplate.cpp
index d94cb0d0f4854..7c6af5793fc55 100644
--- a/lib/Sema/SemaTemplate.cpp
+++ b/lib/Sema/SemaTemplate.cpp
@@ -169,16 +169,16 @@ TemplateNameKind Sema::isTemplateName(Scope *S,
   MemberOfUnknownSpecialization = false;
 
   switch (Name.getKind()) {
-  case UnqualifiedId::IK_Identifier:
+  case UnqualifiedIdKind::IK_Identifier:
     TName = DeclarationName(Name.Identifier);
     break;
 
-  case UnqualifiedId::IK_OperatorFunctionId:
+  case UnqualifiedIdKind::IK_OperatorFunctionId:
     TName = Context.DeclarationNames.getCXXOperatorName(
                                               Name.OperatorFunctionId.Operator);
     break;
 
-  case UnqualifiedId::IK_LiteralOperatorId:
+  case UnqualifiedIdKind::IK_LiteralOperatorId:
     TName = Context.DeclarationNames.getCXXLiteralOperatorName(Name.Identifier);
     break;
 
@@ -3557,7 +3557,7 @@ DeclResult Sema::ActOnVarTemplateSpecialization(
     TemplateParameterList *TemplateParams, StorageClass SC,
     bool IsPartialSpecialization) {
   // D must be variable template id.
-  assert(D.getName().getKind() == UnqualifiedId::IK_TemplateId &&
+  assert(D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId &&
          "Variable template specialization is declared with a template it.");
 
   TemplateIdAnnotation *TemplateId = D.getName().TemplateId;
@@ -4084,8 +4084,8 @@ TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S,
       // We found something; return it.
       auto *LookupRD = dyn_cast<CXXRecordDecl>(LookupCtx);
       if (!AllowInjectedClassName && SS.isSet() && LookupRD &&
-          Name.getKind() == UnqualifiedId::IK_Identifier && Name.Identifier &&
-          LookupRD->getIdentifier() == Name.Identifier) {
+          Name.getKind() == UnqualifiedIdKind::IK_Identifier &&
+          Name.Identifier && LookupRD->getIdentifier() == Name.Identifier) {
         // C++14 [class.qual]p2:
         //   In a lookup in which function names are not ignored and the
         //   nested-name-specifier nominates a class C, if the name specified
@@ -4107,17 +4107,17 @@ TemplateNameKind Sema::ActOnDependentTemplateName(Scope *S,
   NestedNameSpecifier *Qualifier = SS.getScopeRep();
 
   switch (Name.getKind()) {
-  case UnqualifiedId::IK_Identifier:
+  case UnqualifiedIdKind::IK_Identifier:
     Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
                                                               Name.Identifier));
     return TNK_Dependent_template_name;
 
-  case UnqualifiedId::IK_OperatorFunctionId:
+  case UnqualifiedIdKind::IK_OperatorFunctionId:
     Result = TemplateTy::make(Context.getDependentTemplateName(Qualifier,
                                              Name.OperatorFunctionId.Operator));
     return TNK_Function_template;
 
-  case UnqualifiedId::IK_LiteralOperatorId:
+  case UnqualifiedIdKind::IK_LiteralOperatorId:
     llvm_unreachable("literal operator id cannot have a dependent scope");
 
   default:
@@ -9044,7 +9044,7 @@ DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
         return true;
       }
 
-      if (D.getName().getKind() != UnqualifiedId::IK_TemplateId) {
+      if (D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId) {
         // C++1y [temp.explicit]p3:
         //   If the explicit instantiation is for a variable, the unqualified-id
         //   in the declaration shall be a template-id.
@@ -9126,7 +9126,7 @@ DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
   // argument list into our AST format.
   bool HasExplicitTemplateArgs = false;
   TemplateArgumentListInfo TemplateArgs;
-  if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) {
+  if (D.getName().getKind() == UnqualifiedIdKind::IK_TemplateId) {
     TemplateArgs = makeTemplateArgumentListInfo(*this, *D.getName().TemplateId);
     HasExplicitTemplateArgs = true;
   }
@@ -9292,7 +9292,7 @@ DeclResult Sema::ActOnExplicitInstantiation(Scope *S,
   //
   // C++98 has the same restriction, just worded differently.
   FunctionTemplateDecl *FunTmpl = Specialization->getPrimaryTemplate();
-  if (D.getName().getKind() != UnqualifiedId::IK_TemplateId && !FunTmpl &&
+  if (D.getName().getKind() != UnqualifiedIdKind::IK_TemplateId && !FunTmpl &&
       D.getCXXScopeSpec().isSet() &&
       !ScopeSpecifierHasTemplateId(D.getCXXScopeSpec()))
     Diag(D.getIdentifierLoc(),
diff --git a/lib/Sema/SemaTemplateDeduction.cpp b/lib/Sema/SemaTemplateDeduction.cpp
index f8ee602516988..3a0f2ff0004be 100644
--- a/lib/Sema/SemaTemplateDeduction.cpp
+++ b/lib/Sema/SemaTemplateDeduction.cpp
@@ -3940,117 +3940,6 @@ Sema::TemplateDeductionResult Sema::DeduceTemplateArguments(
   return TDK_Success;
 }
 
-/// \brief Given a function declaration (e.g. a generic lambda conversion
-///  function) that contains an 'auto' in its result type, substitute it
-///  with TypeToReplaceAutoWith.  Be careful to pass in the type you want
-///  to replace 'auto' with and not the actual result type you want
-///  to set the function to.
-static inline void
-SubstAutoWithinFunctionReturnType(FunctionDecl *F,
-                                    QualType TypeToReplaceAutoWith, Sema &S) {
-  assert(!TypeToReplaceAutoWith->getContainedAutoType());
-  QualType AutoResultType = F->getReturnType();
-  assert(AutoResultType->getContainedAutoType());
-  QualType DeducedResultType = S.SubstAutoType(AutoResultType,
-                                               TypeToReplaceAutoWith);
-  S.Context.adjustDeducedFunctionResultType(F, DeducedResultType);
-}
-
-/// \brief Given a specialized conversion operator of a generic lambda
-/// create the corresponding specializations of the call operator and
-/// the static-invoker. If the return type of the call operator is auto,
-/// deduce its return type and check if that matches the
-/// return type of the destination function ptr.
-
-static inline Sema::TemplateDeductionResult
-SpecializeCorrespondingLambdaCallOperatorAndInvoker(
-    CXXConversionDecl *ConversionSpecialized,
-    SmallVectorImpl<DeducedTemplateArgument> &DeducedArguments,
-    QualType ReturnTypeOfDestFunctionPtr,
-    TemplateDeductionInfo &TDInfo,
-    Sema &S) {
-
-  CXXRecordDecl *LambdaClass = ConversionSpecialized->getParent();
-  assert(LambdaClass && LambdaClass->isGenericLambda());
-
-  CXXMethodDecl *CallOpGeneric = LambdaClass->getLambdaCallOperator();
-  QualType CallOpResultType = CallOpGeneric->getReturnType();
-  const bool GenericLambdaCallOperatorHasDeducedReturnType =
-      CallOpResultType->getContainedAutoType();
-
-  FunctionTemplateDecl *CallOpTemplate =
-      CallOpGeneric->getDescribedFunctionTemplate();
-
-  FunctionDecl *CallOpSpecialized = nullptr;
-  // Use the deduced arguments of the conversion function, to specialize our
-  // generic lambda's call operator.
-  if (Sema::TemplateDeductionResult Result
-      = S.FinishTemplateArgumentDeduction(CallOpTemplate,
-                                          DeducedArguments,
-                                          0, CallOpSpecialized, TDInfo))
-    return Result;
-
-  // If we need to deduce the return type, do so (instantiates the callop).
-  if (GenericLambdaCallOperatorHasDeducedReturnType &&
-      CallOpSpecialized->getReturnType()->isUndeducedType())
-    S.DeduceReturnType(CallOpSpecialized,
-                       CallOpSpecialized->getPointOfInstantiation(),
-                       /*Diagnose*/ true);
-
-  // Check to see if the return type of the destination ptr-to-function
-  // matches the return type of the call operator.
-  if (!S.Context.hasSameType(CallOpSpecialized->getReturnType(),
-                             ReturnTypeOfDestFunctionPtr))
-    return Sema::TDK_NonDeducedMismatch;
-  // Since we have succeeded in matching the source and destination
-  // ptr-to-functions (now including return type), and have successfully
-  // specialized our corresponding call operator, we are ready to
-  // specialize the static invoker with the deduced arguments of our
-  // ptr-to-function.
-  FunctionDecl *InvokerSpecialized = nullptr;
-  FunctionTemplateDecl *InvokerTemplate = LambdaClass->
-                  getLambdaStaticInvoker()->getDescribedFunctionTemplate();
-
-#ifndef NDEBUG
-  Sema::TemplateDeductionResult LLVM_ATTRIBUTE_UNUSED Result =
-#endif
-    S.FinishTemplateArgumentDeduction(InvokerTemplate, DeducedArguments, 0,
-          InvokerSpecialized, TDInfo);
-  assert(Result == Sema::TDK_Success &&
-    "If the call operator succeeded so should the invoker!");
-  // Set the result type to match the corresponding call operator
-  // specialization's result type.
-  if (GenericLambdaCallOperatorHasDeducedReturnType &&
-      InvokerSpecialized->getReturnType()->isUndeducedType()) {
-    // Be sure to get the type to replace 'auto' with and not
-    // the full result type of the call op specialization
-    // to substitute into the 'auto' of the invoker and conversion
-    // function.
-    // For e.g.
-    //  int* (*fp)(int*) = [](auto* a) -> auto* { return a; };
-    // We don't want to subst 'int*' into 'auto' to get int**.
-
-    QualType TypeToReplaceAutoWith = CallOpSpecialized->getReturnType()
-                                         ->getContainedAutoType()
-                                         ->getDeducedType();
-    SubstAutoWithinFunctionReturnType(InvokerSpecialized,
-        TypeToReplaceAutoWith, S);
-    SubstAutoWithinFunctionReturnType(ConversionSpecialized,
-        TypeToReplaceAutoWith, S);
-  }
-
-  // Ensure that static invoker doesn't have a const qualifier.
-  // FIXME: When creating the InvokerTemplate in SemaLambda.cpp
-  // do not use the CallOperator's TypeSourceInfo which allows
-  // the const qualifier to leak through.
-  const FunctionProtoType *InvokerFPT = InvokerSpecialized->
-                  getType().getTypePtr()->castAs<FunctionProtoType>();
-  FunctionProtoType::ExtProtoInfo EPI = InvokerFPT->getExtProtoInfo();
-  EPI.TypeQuals = 0;
-  InvokerSpecialized->setType(S.Context.getFunctionType(
-      InvokerFPT->getReturnType(), InvokerFPT->getParamTypes(), EPI));
-  return Sema::TDK_Success;
-}
 /// \brief Deduce template arguments for a templated conversion
 /// function (C++ [temp.deduct.conv]) and, if successful, produce a
 /// conversion function template specialization.
@@ -4158,35 +4047,6 @@ Sema::DeduceTemplateArguments(FunctionTemplateDecl *ConversionTemplate,
       = FinishTemplateArgumentDeduction(ConversionTemplate, Deduced, 0,
                                         ConversionSpecialized, Info);
   Specialization = cast_or_null<CXXConversionDecl>(ConversionSpecialized);
-
-  // If the conversion operator is being invoked on a lambda closure to convert
-  // to a ptr-to-function, use the deduced arguments from the conversion
-  // function to specialize the corresponding call operator.
-  //   e.g., int (*fp)(int) = [](auto a) { return a; };
-  if (Result == TDK_Success && isLambdaConversionOperator(ConversionGeneric)) {
-
-    // Get the return type of the destination ptr-to-function we are converting
-    // to.  This is necessary for matching the lambda call operator's return
-    // type to that of the destination ptr-to-function's return type.
-    assert(A->isPointerType() &&
-        "Can only convert from lambda to ptr-to-function");
-    const FunctionType *ToFunType =
-        A->getPointeeType().getTypePtr()->getAs<FunctionType>();
-    const QualType DestFunctionPtrReturnType = ToFunType->getReturnType();
-
-    // Create the corresponding specializations of the call operator and
-    // the static-invoker; and if the return type is auto,
-    // deduce the return type and check if it matches the
-    // DestFunctionPtrReturnType.
-    // For instance:
-    //   auto L = [](auto a) { return f(a); };
-    //   int (*fp)(int) = L;
-    //   char (*fp2)(int) = L; <-- Not OK.
-
-    Result = SpecializeCorrespondingLambdaCallOperatorAndInvoker(
-        Specialization, Deduced, DestFunctionPtrReturnType,
-        Info, *this);
-  }
   return Result;
 }
 
@@ -4536,6 +4396,43 @@ bool Sema::DeduceReturnType(FunctionDecl *FD, SourceLocation Loc,
                             bool Diagnose) {
   assert(FD->getReturnType()->isUndeducedType());
 
+  // For a lambda's conversion operator, deduce any 'auto' or 'decltype(auto)'
+  // within the return type from the call operator's type.
+  if (isLambdaConversionOperator(FD)) {
+    CXXRecordDecl *Lambda = cast<CXXMethodDecl>(FD)->getParent();
+    FunctionDecl *CallOp = Lambda->getLambdaCallOperator();
+
+    // For a generic lambda, instantiate the call operator if needed. 
+    if (auto *Args = FD->getTemplateSpecializationArgs()) {
+      CallOp = InstantiateFunctionDeclaration(
+          CallOp->getDescribedFunctionTemplate(), Args, Loc);
+      if (!CallOp || CallOp->isInvalidDecl())
+        return true;
+
+      // We might need to deduce the return type by instantiating the definition
+      // of the operator() function.
+      if (CallOp->getReturnType()->isUndeducedType())
+        InstantiateFunctionDefinition(Loc, CallOp);
+    }
+
+    if (CallOp->isInvalidDecl())
+      return true;
+    assert(!CallOp->getReturnType()->isUndeducedType() &&
+           "failed to deduce lambda return type");
+
+    // Build the new return type from scratch.
+    QualType RetType = getLambdaConversionFunctionResultType(
+        CallOp->getType()->castAs<FunctionProtoType>());
+    if (FD->getReturnType()->getAs<PointerType>())
+      RetType = Context.getPointerType(RetType);
+    else {
+      assert(FD->getReturnType()->getAs<BlockPointerType>());
+      RetType = Context.getBlockPointerType(RetType);
+    }
+    Context.adjustDeducedFunctionResultType(FD, RetType);
+    return false;
+  }
+
   if (FD->getTemplateInstantiationPattern())
     InstantiateFunctionDefinition(Loc, FD);
 
diff --git a/lib/Sema/SemaTemplateInstantiateDecl.cpp b/lib/Sema/SemaTemplateInstantiateDecl.cpp
index d8af8f34530b1..ab68e7e671de6 100644
--- a/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -3729,6 +3729,30 @@ TemplateDeclInstantiator::InitMethodInstantiation(CXXMethodDecl *New,
   return false;
 }
 
+/// Instantiate (or find existing instantiation of) a function template with a
+/// given set of template arguments.
+///
+/// Usually this should not be used, and template argument deduction should be
+/// used in its place.
+FunctionDecl *
+Sema::InstantiateFunctionDeclaration(FunctionTemplateDecl *FTD,
+                                     const TemplateArgumentList *Args,
+                                     SourceLocation Loc) {
+  FunctionDecl *FD = FTD->getTemplatedDecl();
+
+  sema::TemplateDeductionInfo Info(Loc);
+  InstantiatingTemplate Inst(
+      *this, Loc, FTD, Args->asArray(),
+      CodeSynthesisContext::ExplicitTemplateArgumentSubstitution, Info);
+  if (Inst.isInvalid())
+    return nullptr;
+
+  ContextRAII SavedContext(*this, FD);
+  MultiLevelTemplateArgumentList MArgs(*Args);
+
+  return cast_or_null<FunctionDecl>(SubstDecl(FD, FD->getParent(), MArgs));
+}
+
 /// In the MS ABI, we need to instantiate default arguments of dllexported
 /// default constructors along with the constructor definition. This allows IR
 /// gen to emit a constructor closure which calls the default constructor with
@@ -3812,7 +3836,8 @@ void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
       PendingInstantiations.push_back(
         std::make_pair(Function, PointOfInstantiation));
     } else if (TSK == TSK_ImplicitInstantiation) {
-      if (AtEndOfTU && !getDiagnostics().hasErrorOccurred()) {
+      if (AtEndOfTU && !getDiagnostics().hasErrorOccurred() &&
+          !getSourceManager().isInSystemHeader(PatternDecl->getLocStart())) {
         Diag(PointOfInstantiation, diag::warn_func_template_missing)
           << Function;
         Diag(PatternDecl->getLocation(), diag::note_forward_template_decl);
@@ -4347,7 +4372,8 @@ void Sema::InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
         std::make_pair(Var, PointOfInstantiation));
     } else if (TSK == TSK_ImplicitInstantiation) {
       // Warn about missing definition at the end of translation unit.
-      if (AtEndOfTU && !getDiagnostics().hasErrorOccurred()) {
+      if (AtEndOfTU && !getDiagnostics().hasErrorOccurred() &&
+          !getSourceManager().isInSystemHeader(PatternDecl->getLocStart())) {
         Diag(PointOfInstantiation, diag::warn_var_template_missing)
           << Var;
         Diag(PatternDecl->getLocation(), diag::note_forward_template_decl);
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 2530b766f5f72..af060cf21b5fa 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -47,7 +47,7 @@ enum TypeDiagSelector {
 /// isOmittedBlockReturnType - Return true if this declarator is missing a
 /// return type because this is a omitted return type on a block literal.
 static bool isOmittedBlockReturnType(const Declarator &D) {
-  if (D.getContext() != Declarator::BlockLiteralContext ||
+  if (D.getContext() != DeclaratorContext::BlockLiteralContext ||
       D.getDeclSpec().hasTypeSpecifier())
     return false;
 
@@ -1291,11 +1291,12 @@ static QualType ConvertDeclSpecToType(TypeProcessingState &state) {
     // The declspec is always missing in a lambda expr context; it is either
     // specified with a trailing return type or inferred.
     if (S.getLangOpts().CPlusPlus14 &&
-        declarator.getContext() == Declarator::LambdaExprContext) {
+        declarator.getContext() == DeclaratorContext::LambdaExprContext) {
       // In C++1y, a lambda's implicit return type is 'auto'.
       Result = Context.getAutoDeductType();
       break;
-    } else if (declarator.getContext() == Declarator::LambdaExprContext ||
+    } else if (declarator.getContext() ==
+                   DeclaratorContext::LambdaExprContext ||
                checkOmittedBlockReturnType(S, declarator,
                                            Context.DependentTy)) {
       Result = Context.DependentTy;
@@ -1572,7 +1573,7 @@ static QualType ConvertDeclSpecToType(TypeProcessingState &state) {
 
   // Before we process any type attributes, synthesize a block literal
   // function declarator if necessary.
-  if (declarator.getContext() == Declarator::BlockLiteralContext)
+  if (declarator.getContext() == DeclaratorContext::BlockLiteralContext)
     maybeSynthesizeBlockSignature(state, Result);
 
   // Apply any type attributes from the decl spec.  This may cause the
@@ -2702,7 +2703,7 @@ static void diagnoseRedundantReturnTypeQualifiers(Sema &S, QualType RetTy,
   // If the qualifiers come from a conversion function type, don't diagnose
   // them -- they're not necessarily redundant, since such a conversion
   // operator can be explicitly called as "x.operator const int()".
-  if (D.getName().getKind() == UnqualifiedId::IK_ConversionFunctionId)
+  if (D.getName().getKind() == UnqualifiedIdKind::IK_ConversionFunctionId)
     return;
 
   // Just parens all the way out to the decl specifiers. Diagnose any qualifiers
@@ -2728,11 +2729,11 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
   TagDecl *OwnedTagDecl = nullptr;
 
   switch (D.getName().getKind()) {
-  case UnqualifiedId::IK_ImplicitSelfParam:
-  case UnqualifiedId::IK_OperatorFunctionId:
-  case UnqualifiedId::IK_Identifier:
-  case UnqualifiedId::IK_LiteralOperatorId:
-  case UnqualifiedId::IK_TemplateId:
+  case UnqualifiedIdKind::IK_ImplicitSelfParam:
+  case UnqualifiedIdKind::IK_OperatorFunctionId:
+  case UnqualifiedIdKind::IK_Identifier:
+  case UnqualifiedIdKind::IK_LiteralOperatorId:
+  case UnqualifiedIdKind::IK_TemplateId:
     T = ConvertDeclSpecToType(state);
 
     if (!D.isInvalidType() && D.getDeclSpec().isTypeSpecOwned()) {
@@ -2742,9 +2743,9 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
     }
     break;
 
-  case UnqualifiedId::IK_ConstructorName:
-  case UnqualifiedId::IK_ConstructorTemplateId:
-  case UnqualifiedId::IK_DestructorName:
+  case UnqualifiedIdKind::IK_ConstructorName:
+  case UnqualifiedIdKind::IK_ConstructorTemplateId:
+  case UnqualifiedIdKind::IK_DestructorName:
     // Constructors and destructors don't have return types. Use
     // "void" instead.
     T = SemaRef.Context.VoidTy;
@@ -2752,13 +2753,13 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
                      D.getDeclSpec().getAttributes().getList());
     break;
 
-  case UnqualifiedId::IK_DeductionGuideName:
+  case UnqualifiedIdKind::IK_DeductionGuideName:
     // Deduction guides have a trailing return type and no type in their
     // decl-specifier sequence. Use a placeholder return type for now.
     T = SemaRef.Context.DependentTy;
     break;
 
-  case UnqualifiedId::IK_ConversionFunctionId:
+  case UnqualifiedIdKind::IK_ConversionFunctionId:
     // The result type of a conversion function is the type that it
     // converts to.
     T = SemaRef.GetTypeFromParser(D.getName().ConversionFunctionId,
@@ -2780,16 +2781,16 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
         (Auto && Auto->getKeyword() != AutoTypeKeyword::GNUAutoType);
 
     switch (D.getContext()) {
-    case Declarator::LambdaExprContext:
+    case DeclaratorContext::LambdaExprContext:
       // Declared return type of a lambda-declarator is implicit and is always
       // 'auto'.
       break;
-    case Declarator::ObjCParameterContext:
-    case Declarator::ObjCResultContext:
-    case Declarator::PrototypeContext:
+    case DeclaratorContext::ObjCParameterContext:
+    case DeclaratorContext::ObjCResultContext:
+    case DeclaratorContext::PrototypeContext:
       Error = 0;  
       break;
-    case Declarator::LambdaExprParameterContext:
+    case DeclaratorContext::LambdaExprParameterContext:
       // In C++14, generic lambdas allow 'auto' in their parameters.
       if (!SemaRef.getLangOpts().CPlusPlus14 ||
           !Auto || Auto->getKeyword() != AutoTypeKeyword::Auto)
@@ -2821,7 +2822,7 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
             T, QualType(CorrespondingTemplateParam->getTypeForDecl(), 0));
       }
       break;
-    case Declarator::MemberContext: {
+    case DeclaratorContext::MemberContext: {
       if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static ||
           D.isFunctionDeclarator())
         break;
@@ -2837,57 +2838,57 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
         Error = 20; // Friend type
       break;
     }
-    case Declarator::CXXCatchContext:
-    case Declarator::ObjCCatchContext:
+    case DeclaratorContext::CXXCatchContext:
+    case DeclaratorContext::ObjCCatchContext:
       Error = 7; // Exception declaration
       break;
-    case Declarator::TemplateParamContext:
+    case DeclaratorContext::TemplateParamContext:
       if (isa<DeducedTemplateSpecializationType>(Deduced))
         Error = 19; // Template parameter
       else if (!SemaRef.getLangOpts().CPlusPlus17)
         Error = 8; // Template parameter (until C++17)
       break;
-    case Declarator::BlockLiteralContext:
+    case DeclaratorContext::BlockLiteralContext:
       Error = 9; // Block literal
       break;
-    case Declarator::TemplateTypeArgContext:
+    case DeclaratorContext::TemplateTypeArgContext:
       Error = 10; // Template type argument
       break;
-    case Declarator::AliasDeclContext:
-    case Declarator::AliasTemplateContext:
+    case DeclaratorContext::AliasDeclContext:
+    case DeclaratorContext::AliasTemplateContext:
       Error = 12; // Type alias
       break;
-    case Declarator::TrailingReturnContext:
+    case DeclaratorContext::TrailingReturnContext:
       if (!SemaRef.getLangOpts().CPlusPlus14 || !IsCXXAutoType)
         Error = 13; // Function return type
       break;
-    case Declarator::ConversionIdContext:
+    case DeclaratorContext::ConversionIdContext:
       if (!SemaRef.getLangOpts().CPlusPlus14 || !IsCXXAutoType)
         Error = 14; // conversion-type-id
       break;
-    case Declarator::FunctionalCastContext:
+    case DeclaratorContext::FunctionalCastContext:
       if (isa<DeducedTemplateSpecializationType>(Deduced))
         break;
       LLVM_FALLTHROUGH;
-    case Declarator::TypeNameContext:
+    case DeclaratorContext::TypeNameContext:
       Error = 15; // Generic
       break;
-    case Declarator::FileContext:
-    case Declarator::BlockContext:
-    case Declarator::ForContext:
-    case Declarator::InitStmtContext:
-    case Declarator::ConditionContext:
+    case DeclaratorContext::FileContext:
+    case DeclaratorContext::BlockContext:
+    case DeclaratorContext::ForContext:
+    case DeclaratorContext::InitStmtContext:
+    case DeclaratorContext::ConditionContext:
       // FIXME: P0091R3 (erroneously) does not permit class template argument
       // deduction in conditions, for-init-statements, and other declarations
       // that are not simple-declarations.
       break;
-    case Declarator::CXXNewContext:
+    case DeclaratorContext::CXXNewContext:
       // FIXME: P0091R3 does not permit class template argument deduction here,
       // but we follow GCC and allow it anyway.
       if (!IsCXXAutoType && !isa<DeducedTemplateSpecializationType>(Deduced))
         Error = 17; // 'new' type
       break;
-    case Declarator::KNRTypeListContext:
+    case DeclaratorContext::KNRTypeListContext:
       Error = 18; // K&R function parameter
       break;
     }
@@ -2916,7 +2917,7 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
     }
 
     SourceRange AutoRange = D.getDeclSpec().getTypeSpecTypeLoc();
-    if (D.getName().getKind() == UnqualifiedId::IK_ConversionFunctionId)
+    if (D.getName().getKind() == UnqualifiedIdKind::IK_ConversionFunctionId)
       AutoRange = D.getName().getSourceRange();
 
     if (Error != -1) {
@@ -2959,47 +2960,47 @@ static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
     // or enumeration in a type-specifier-seq.
     unsigned DiagID = 0;
     switch (D.getContext()) {
-    case Declarator::TrailingReturnContext:
+    case DeclaratorContext::TrailingReturnContext:
       // Class and enumeration definitions are syntactically not allowed in
       // trailing return types.
       llvm_unreachable("parser should not have allowed this");
       break;
-    case Declarator::FileContext:
-    case Declarator::MemberContext:
-    case Declarator::BlockContext:
-    case Declarator::ForContext:
-    case Declarator::InitStmtContext:
-    case Declarator::BlockLiteralContext:
-    case Declarator::LambdaExprContext:
+    case DeclaratorContext::FileContext:
+    case DeclaratorContext::MemberContext:
+    case DeclaratorContext::BlockContext:
+    case DeclaratorContext::ForContext:
+    case DeclaratorContext::InitStmtContext:
+    case DeclaratorContext::BlockLiteralContext:
+    case DeclaratorContext::LambdaExprContext:
       // C++11 [dcl.type]p3:
       //   A type-specifier-seq shall not define a class or enumeration unless
       //   it appears in the type-id of an alias-declaration (7.1.3) that is not
       //   the declaration of a template-declaration.
-    case Declarator::AliasDeclContext:
+    case DeclaratorContext::AliasDeclContext:
       break;
-    case Declarator::AliasTemplateContext:
+    case DeclaratorContext::AliasTemplateContext:
       DiagID = diag::err_type_defined_in_alias_template;
       break;
-    case Declarator::TypeNameContext:
-    case Declarator::FunctionalCastContext:
-    case Declarator::ConversionIdContext:
-    case Declarator::TemplateParamContext:
-    case Declarator::CXXNewContext:
-    case Declarator::CXXCatchContext:
-    case Declarator::ObjCCatchContext:
-    case Declarator::TemplateTypeArgContext:
+    case DeclaratorContext::TypeNameContext:
+    case DeclaratorContext::FunctionalCastContext:
+    case DeclaratorContext::ConversionIdContext:
+    case DeclaratorContext::TemplateParamContext:
+    case DeclaratorContext::CXXNewContext:
+    case DeclaratorContext::CXXCatchContext:
+    case DeclaratorContext::ObjCCatchContext:
+    case DeclaratorContext::TemplateTypeArgContext:
       DiagID = diag::err_type_defined_in_type_specifier;
       break;
-    case Declarator::PrototypeContext:
-    case Declarator::LambdaExprParameterContext:
-    case Declarator::ObjCParameterContext:
-    case Declarator::ObjCResultContext:
-    case Declarator::KNRTypeListContext:
+    case DeclaratorContext::PrototypeContext:
+    case DeclaratorContext::LambdaExprParameterContext:
+    case DeclaratorContext::ObjCParameterContext:
+    case DeclaratorContext::ObjCResultContext:
+    case DeclaratorContext::KNRTypeListContext:
       // C++ [dcl.fct]p6:
       //   Types shall not be defined in return or parameter types.
       DiagID = diag::err_type_defined_in_param_type;
       break;
-    case Declarator::ConditionContext:
+    case DeclaratorContext::ConditionContext:
       // C++ 6.4p2:
       // The type-specifier-seq shall not contain typedef and shall not declare
       // a new class or enumeration.
@@ -3048,7 +3049,7 @@ static void warnAboutAmbiguousFunction(Sema &S, Declarator &D,
 
   // Inside a condition, a direct initializer is not permitted. We allow one to
   // be parsed in order to give better diagnostics in condition parsing.
-  if (D.getContext() == Declarator::ConditionContext)
+  if (D.getContext() == DeclaratorContext::ConditionContext)
     return;
 
   SourceRange ParenRange(DeclType.Loc, DeclType.EndLoc);
@@ -3164,7 +3165,7 @@ static void warnAboutRedundantParens(Sema &S, Declarator &D, QualType T) {
 
     case DeclaratorChunk::Function:
       // In a new-type-id, function chunks require parentheses.
-      if (D.getContext() == Declarator::CXXNewContext)
+      if (D.getContext() == DeclaratorContext::CXXNewContext)
         return;
       // FIXME: "A(f())" deserves a vexing-parse warning, not just a
       // redundant-parens warning, but we don't know whether the function
@@ -3282,7 +3283,7 @@ getCCForDeclaratorChunk(Sema &S, Declarator &D,
       // in a member pointer.
       IsCXXInstanceMethod =
           D.getTypeObject(I).Kind == DeclaratorChunk::MemberPointer;
-    } else if (D.getContext() == Declarator::LambdaExprContext) {
+    } else if (D.getContext() == DeclaratorContext::LambdaExprContext) {
       // This can only be a call operator for a lambda, which is an instance
       // method.
       IsCXXInstanceMethod = true;
@@ -3779,8 +3780,8 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
   // Does this declaration declare a typedef-name?
   bool IsTypedefName =
     D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef ||
-    D.getContext() == Declarator::AliasDeclContext ||
-    D.getContext() == Declarator::AliasTemplateContext;
+    D.getContext() == DeclaratorContext::AliasDeclContext ||
+    D.getContext() == DeclaratorContext::AliasTemplateContext;
 
   // Does T refer to a function type with a cv-qualifier or a ref-qualifier?
   bool IsQualifiedFunction = T->isFunctionProtoType() &&
@@ -3909,14 +3910,14 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
   } else {
     bool isFunctionOrMethod = false;
     switch (auto context = state.getDeclarator().getContext()) {
-    case Declarator::ObjCParameterContext:
-    case Declarator::ObjCResultContext:
-    case Declarator::PrototypeContext:
-    case Declarator::TrailingReturnContext:
+    case DeclaratorContext::ObjCParameterContext:
+    case DeclaratorContext::ObjCResultContext:
+    case DeclaratorContext::PrototypeContext:
+    case DeclaratorContext::TrailingReturnContext:
       isFunctionOrMethod = true;
       LLVM_FALLTHROUGH;
 
-    case Declarator::MemberContext:
+    case DeclaratorContext::MemberContext:
       if (state.getDeclarator().isObjCIvar() && !isFunctionOrMethod) {
         complainAboutMissingNullability = CAMN_No;
         break;
@@ -3930,8 +3931,8 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
 
       LLVM_FALLTHROUGH;
 
-    case Declarator::FileContext:
-    case Declarator::KNRTypeListContext: {
+    case DeclaratorContext::FileContext:
+    case DeclaratorContext::KNRTypeListContext: {
       complainAboutMissingNullability = CAMN_Yes;
 
       // Nullability inference depends on the type and declarator.
@@ -3947,8 +3948,9 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
         if (inAssumeNonNullRegion) {
           complainAboutInferringWithinChunk = wrappingKind;
           inferNullability = NullabilityKind::NonNull;
-          inferNullabilityCS = (context == Declarator::ObjCParameterContext ||
-                                context == Declarator::ObjCResultContext);
+          inferNullabilityCS =
+              (context == DeclaratorContext::ObjCParameterContext ||
+               context == DeclaratorContext::ObjCResultContext);
         }
         break;
 
@@ -3988,26 +3990,26 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
       break;
     }
 
-    case Declarator::ConversionIdContext:
+    case DeclaratorContext::ConversionIdContext:
       complainAboutMissingNullability = CAMN_Yes;
       break;
 
-    case Declarator::AliasDeclContext:
-    case Declarator::AliasTemplateContext:
-    case Declarator::BlockContext:
-    case Declarator::BlockLiteralContext:
-    case Declarator::ConditionContext:
-    case Declarator::CXXCatchContext:
-    case Declarator::CXXNewContext:
-    case Declarator::ForContext:
-    case Declarator::InitStmtContext:
-    case Declarator::LambdaExprContext:
-    case Declarator::LambdaExprParameterContext:
-    case Declarator::ObjCCatchContext:
-    case Declarator::TemplateParamContext:
-    case Declarator::TemplateTypeArgContext:
-    case Declarator::TypeNameContext:
-    case Declarator::FunctionalCastContext:
+    case DeclaratorContext::AliasDeclContext:
+    case DeclaratorContext::AliasTemplateContext:
+    case DeclaratorContext::BlockContext:
+    case DeclaratorContext::BlockLiteralContext:
+    case DeclaratorContext::ConditionContext:
+    case DeclaratorContext::CXXCatchContext:
+    case DeclaratorContext::CXXNewContext:
+    case DeclaratorContext::ForContext:
+    case DeclaratorContext::InitStmtContext:
+    case DeclaratorContext::LambdaExprContext:
+    case DeclaratorContext::LambdaExprParameterContext:
+    case DeclaratorContext::ObjCCatchContext:
+    case DeclaratorContext::TemplateParamContext:
+    case DeclaratorContext::TemplateTypeArgContext:
+    case DeclaratorContext::TypeNameContext:
+    case DeclaratorContext::FunctionalCastContext:
       // Don't infer in these contexts.
       break;
     }
@@ -4243,7 +4245,7 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
       // array type, ...
       if (ASM == ArrayType::Static || ATI.TypeQuals) {
         if (!(D.isPrototypeContext() ||
-              D.getContext() == Declarator::KNRTypeListContext)) {
+              D.getContext() == DeclaratorContext::KNRTypeListContext)) {
           S.Diag(DeclType.Loc, diag::err_array_static_outside_prototype) <<
               (ASM == ArrayType::Static ? "'static'" : "type qualifier");
           // Remove the 'static' and the type qualifiers.
@@ -4267,7 +4269,8 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
       const AutoType *AT = T->getContainedAutoType();
       // Allow arrays of auto if we are a generic lambda parameter.
       // i.e. [](auto (&array)[5]) { return array[0]; }; OK
-      if (AT && D.getContext() != Declarator::LambdaExprParameterContext) {
+      if (AT &&
+          D.getContext() != DeclaratorContext::LambdaExprParameterContext) {
         // We've already diagnosed this for decltype(auto).
         if (!AT->isDecltypeAuto())
           S.Diag(DeclType.Loc, diag::err_illegal_decl_array_of_auto)
@@ -4319,14 +4322,14 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
               << T << D.getSourceRange();
             D.setInvalidType(true);
           } else if (D.getName().getKind() ==
-                     UnqualifiedId::IK_DeductionGuideName) {
+                     UnqualifiedIdKind::IK_DeductionGuideName) {
             if (T != Context.DependentTy) {
               S.Diag(D.getDeclSpec().getLocStart(),
                      diag::err_deduction_guide_with_complex_decl)
                   << D.getSourceRange();
               D.setInvalidType(true);
             }
-          } else if (D.getContext() != Declarator::LambdaExprContext &&
+          } else if (D.getContext() != DeclaratorContext::LambdaExprContext &&
                      (T.hasQualifiers() || !isa<AutoType>(T) ||
                       cast<AutoType>(T)->getKeyword() !=
                           AutoTypeKeyword::Auto)) {
@@ -4347,12 +4350,13 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
       // C99 6.7.5.3p1: The return type may not be a function or array type.
       // For conversion functions, we'll diagnose this particular error later.
       if (!D.isInvalidType() && (T->isArrayType() || T->isFunctionType()) &&
-          (D.getName().getKind() != UnqualifiedId::IK_ConversionFunctionId)) {
+          (D.getName().getKind() !=
+           UnqualifiedIdKind::IK_ConversionFunctionId)) {
         unsigned diagID = diag::err_func_returning_array_function;
         // Last processing chunk in block context means this function chunk
         // represents the block.
         if (chunkIndex == 0 &&
-            D.getContext() == Declarator::BlockLiteralContext)
+            D.getContext() == DeclaratorContext::BlockLiteralContext)
           diagID = diag::err_block_returning_array_function;
         S.Diag(DeclType.Loc, diagID) << T->isFunctionType() << T;
         T = Context.IntTy;
@@ -4490,8 +4494,8 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
       if (IsTypedefName && FTI.getExceptionSpecType() && !LangOpts.CPlusPlus17)
         S.Diag(FTI.getExceptionSpecLocBeg(),
                diag::err_exception_spec_in_typedef)
-            << (D.getContext() == Declarator::AliasDeclContext ||
-                D.getContext() == Declarator::AliasTemplateContext);
+            << (D.getContext() == DeclaratorContext::AliasDeclContext ||
+                D.getContext() == DeclaratorContext::AliasTemplateContext);
 
       // If we see "T var();" or "T var(T());" at block scope, it is probably
       // an attempt to initialize a variable, not a function declaration.
@@ -4763,7 +4767,7 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
         break;
       case DeclaratorChunk::Function: {
         const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun;
-        if (FTI.NumParams == 0)
+        if (FTI.NumParams == 0 && !FTI.isVariadic)
           S.Diag(DeclType.Loc, diag::warn_strict_prototypes)
               << IsBlock
               << FixItHint::CreateInsertion(FTI.getRParenLoc(), "void");
@@ -4791,11 +4795,11 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
     // Core issue 547 also allows cv-qualifiers on function types that are
     // top-level template type arguments.
     enum { NonMember, Member, DeductionGuide } Kind = NonMember;
-    if (D.getName().getKind() == UnqualifiedId::IK_DeductionGuideName)
+    if (D.getName().getKind() == UnqualifiedIdKind::IK_DeductionGuideName)
       Kind = DeductionGuide;
     else if (!D.getCXXScopeSpec().isSet()) {
-      if ((D.getContext() == Declarator::MemberContext ||
-           D.getContext() == Declarator::LambdaExprContext) &&
+      if ((D.getContext() == DeclaratorContext::MemberContext ||
+           D.getContext() == DeclaratorContext::LambdaExprContext) &&
           !D.getDeclSpec().isFriendSpecified())
         Kind = Member;
     } else {
@@ -4824,7 +4828,7 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
         !(Kind == Member &&
           D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) &&
         !IsTypedefName &&
-        D.getContext() != Declarator::TemplateTypeArgContext) {
+        D.getContext() != DeclaratorContext::TemplateTypeArgContext) {
       SourceLocation Loc = D.getLocStart();
       SourceRange RemovalRange;
       unsigned I;
@@ -4890,8 +4894,8 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
     //   only be used in a parameter-declaration. Such a parameter-declaration
     //   is a parameter pack (14.5.3). [...]
     switch (D.getContext()) {
-    case Declarator::PrototypeContext:
-    case Declarator::LambdaExprParameterContext:
+    case DeclaratorContext::PrototypeContext:
+    case DeclaratorContext::LambdaExprParameterContext:
       // C++0x [dcl.fct]p13:
       //   [...] When it is part of a parameter-declaration-clause, the
       //   parameter pack is a function parameter pack (14.5.3). The type T
@@ -4910,7 +4914,7 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
         T = Context.getPackExpansionType(T, None);
       }
       break;
-    case Declarator::TemplateParamContext:
+    case DeclaratorContext::TemplateParamContext:
       // C++0x [temp.param]p15:
       //   If a template-parameter is a [...] is a parameter-declaration that
       //   declares a parameter pack (8.3.5), then the template-parameter is a
@@ -4928,27 +4932,29 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
                  : diag::ext_variadic_templates);
       break;
 
-    case Declarator::FileContext:
-    case Declarator::KNRTypeListContext:
-    case Declarator::ObjCParameterContext:  // FIXME: special diagnostic here?
-    case Declarator::ObjCResultContext:     // FIXME: special diagnostic here?
-    case Declarator::TypeNameContext:
-    case Declarator::FunctionalCastContext:
-    case Declarator::CXXNewContext:
-    case Declarator::AliasDeclContext:
-    case Declarator::AliasTemplateContext:
-    case Declarator::MemberContext:
-    case Declarator::BlockContext:
-    case Declarator::ForContext:
-    case Declarator::InitStmtContext:
-    case Declarator::ConditionContext:
-    case Declarator::CXXCatchContext:
-    case Declarator::ObjCCatchContext:
-    case Declarator::BlockLiteralContext:
-    case Declarator::LambdaExprContext:
-    case Declarator::ConversionIdContext:
-    case Declarator::TrailingReturnContext:
-    case Declarator::TemplateTypeArgContext:
+    case DeclaratorContext::FileContext:
+    case DeclaratorContext::KNRTypeListContext:
+    case DeclaratorContext::ObjCParameterContext:  // FIXME: special diagnostic
+                                                   // here?
+    case DeclaratorContext::ObjCResultContext:     // FIXME: special diagnostic
+                                                   // here?
+    case DeclaratorContext::TypeNameContext:
+    case DeclaratorContext::FunctionalCastContext:
+    case DeclaratorContext::CXXNewContext:
+    case DeclaratorContext::AliasDeclContext:
+    case DeclaratorContext::AliasTemplateContext:
+    case DeclaratorContext::MemberContext:
+    case DeclaratorContext::BlockContext:
+    case DeclaratorContext::ForContext:
+    case DeclaratorContext::InitStmtContext:
+    case DeclaratorContext::ConditionContext:
+    case DeclaratorContext::CXXCatchContext:
+    case DeclaratorContext::ObjCCatchContext:
+    case DeclaratorContext::BlockLiteralContext:
+    case DeclaratorContext::LambdaExprContext:
+    case DeclaratorContext::ConversionIdContext:
+    case DeclaratorContext::TrailingReturnContext:
+    case DeclaratorContext::TemplateTypeArgContext:
       // FIXME: We may want to allow parameter packs in block-literal contexts
       // in the future.
       S.Diag(D.getEllipsisLoc(),
@@ -5637,9 +5643,9 @@ TypeResult Sema::ActOnTypeName(Scope *S, Declarator &D) {
   // to apply them to the actual parameter declaration.
   // Likewise, we don't want to do this for alias declarations, because
   // we are actually going to build a declaration from this eventually.
-  if (D.getContext() != Declarator::ObjCParameterContext &&
-      D.getContext() != Declarator::AliasDeclContext &&
-      D.getContext() != Declarator::AliasTemplateContext)
+  if (D.getContext() != DeclaratorContext::ObjCParameterContext &&
+      D.getContext() != DeclaratorContext::AliasDeclContext &&
+      D.getContext() != DeclaratorContext::AliasTemplateContext)
     checkUnusedDeclAttributes(D);
 
   if (getLangOpts().CPlusPlus) {
@@ -7066,7 +7072,7 @@ static void deduceOpenCLImplicitAddrSpace(TypeProcessingState &State,
       IsFuncReturnType || IsFuncType ||
       // Do not deduce addr space for member types of struct, except the pointee
       // type of a pointer member type.
-      (D.getContext() == Declarator::MemberContext && !IsPointee) ||
+      (D.getContext() == DeclaratorContext::MemberContext && !IsPointee) ||
       // Do not deduce addr space for types used to define a typedef and the
       // typedef itself, except the pointee type of a pointer type which is used
       // to define the typedef.
@@ -7098,7 +7104,7 @@ static void deduceOpenCLImplicitAddrSpace(TypeProcessingState &State,
     if (IsPointee) {
       ImpAddr = LangAS::opencl_generic;
     } else {
-      if (D.getContext() == Declarator::FileContext) {
+      if (D.getContext() == DeclaratorContext::FileContext) {
         ImpAddr = LangAS::opencl_global;
       } else {
         if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static ||
diff --git a/lib/StaticAnalyzer/Core/BugReporter.cpp b/lib/StaticAnalyzer/Core/BugReporter.cpp
index dc284888eb032..de0e87bb82494 100644
--- a/lib/StaticAnalyzer/Core/BugReporter.cpp
+++ b/lib/StaticAnalyzer/Core/BugReporter.cpp
@@ -229,7 +229,6 @@ adjustCallLocations(PathPieces &Pieces,
     PathDiagnosticCallPiece *Call = dyn_cast<PathDiagnosticCallPiece>(I->get());
 
     if (!Call) {
-      assert((*I)->getLocation().asLocation().isValid());
       continue;
     }