[OPENMP] Support for -fopenmp-simd option with compilation of simd loops

only.

Added support for -fopenmp-simd option that allows compilation of
simd-based constructs without emission of OpenMP runtime calls.

llvm-svn: 321560

8 files changed, 1007 insertions, 16 deletions

diff --git a/clang/lib/CodeGen/CGDeclCXX.cpp b/clang/lib/CodeGen/CGDeclCXX.cpp
index 04299783170..8c0e01e5624 100644
--- a/clang/lib/CodeGen/CGDeclCXX.cpp
+++ b/clang/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/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index c7dc8337e19..3f81be00f32 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/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/clang/lib/CodeGen/CGOpenMPRuntime.cpp b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
index fa38ee80bf4..784c90a9eb9 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/clang/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/clang/lib/CodeGen/CGOpenMPRuntime.h b/clang/lib/CodeGen/CGOpenMPRuntime.h
index 94a14384137..98e09e09b5e 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.h
+++ b/clang/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/clang/lib/CodeGen/CGStmt.cpp b/clang/lib/CodeGen/CGStmt.cpp
index 91fa49a46ef..97e35e2b6e8 100644
--- a/clang/lib/CodeGen/CGStmt.cpp
+++ b/clang/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/clang/lib/CodeGen/CGStmtOpenMP.cpp b/clang/lib/CodeGen/CGStmtOpenMP.cpp
index f9861735832..26817ac330b 100644
--- a/clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/clang/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/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index dd4c2e43ef6..a7c322d3b95 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -2655,6 +2655,9 @@ 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/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 5bdf81aaf66..df33fc3e820 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/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 =