[Flang][OpenMP][Lower] Split MLIR codegen for clauses and constructs (#86963)

This patch performs several cleanups with the main purpose of
normalizing the code patterns used to trigger codegen for MLIR OpenMP
operations and making the processing of clauses and constructs
independent. The following changes are made:

- Clean up unused `directive` argument to
`ClauseProcessor::processMap()`.
- Move general helper functions in OpenMP.cpp to the appropriate section
of the file.
- Create `gen<OpName>Clauses()` functions containing the clause
processing code specific for the associated OpenMP construct.
- Update `gen<OpName>Op()` functions to call the corresponding
`gen<OpName>Clauses()` function.
- Sort calls to `ClauseProcessor::process<ClauseName>()` alphabetically,
to avoid inadvertently relying on some arbitrary order. Update some
tests that broke due to the order change.
- Normalize `genOMP()` functions so they all delegate the generation of
MLIR to `gen<OpName>Op()` functions following the same pattern.
- Only process `nowait` clause on `TARGET` constructs if not compiling
for the target device.

A later patch can move the calls to `gen<OpName>Clauses()` out of
`gen<OpName>Op()` functions and passing completed clause structures
instead, in preparation to supporting composite constructs. That will
make it possible to reuse clause processing for a given leaf construct
when appearing alone or in a combined or composite construct, while
controlling where the associated code is produced.

6 files changed, 1103 insertions, 858 deletions

diff --git a/flang/lib/Lower/OpenMP/ClauseProcessor.cpp b/flang/lib/Lower/OpenMP/ClauseProcessor.cpp
index ae0d8bd37228..4c51b61f6bf0 100644
--- a/flang/lib/Lower/OpenMP/ClauseProcessor.cpp
+++ b/flang/lib/Lower/OpenMP/ClauseProcessor.cpp
@@ -832,8 +832,8 @@ createMapInfoOp(fir::FirOpBuilder &builder, mlir::Location loc,
 }
 
 bool ClauseProcessor::processMap(
-    mlir::Location currentLocation, const llvm::omp::Directive &directive,
-    Fortran::lower::StatementContext &stmtCtx, mlir::omp::MapClauseOps &result,
+    mlir::Location currentLocation, Fortran::lower::StatementContext &stmtCtx,
+    mlir::omp::MapClauseOps &result,
     llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> *mapSyms,
     llvm::SmallVectorImpl<mlir::Location> *mapSymLocs,
     llvm::SmallVectorImpl<mlir::Type> *mapSymTypes) const {
diff --git a/flang/lib/Lower/OpenMP/ClauseProcessor.h b/flang/lib/Lower/OpenMP/ClauseProcessor.h
index aa2c14b61e75..3f9701310eba 100644
--- a/flang/lib/Lower/OpenMP/ClauseProcessor.h
+++ b/flang/lib/Lower/OpenMP/ClauseProcessor.h
@@ -114,8 +114,7 @@ public:
   // They may be used later on to create the block_arguments for some of the
   // target directives that require it.
   bool processMap(
-      mlir::Location currentLocation, const llvm::omp::Directive &directive,
-      Fortran::lower::StatementContext &stmtCtx,
+      mlir::Location currentLocation, Fortran::lower::StatementContext &stmtCtx,
       mlir::omp::MapClauseOps &result,
       llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> *mapSyms =
           nullptr,
diff --git a/flang/lib/Lower/OpenMP/OpenMP.cpp b/flang/lib/Lower/OpenMP/OpenMP.cpp
index 352ca66e8735..9b9975223666 100644
--- a/flang/lib/Lower/OpenMP/OpenMP.cpp
+++ b/flang/lib/Lower/OpenMP/OpenMP.cpp
@@ -222,6 +222,276 @@ createAndSetPrivatizedLoopVar(Fortran::lower::AbstractConverter &converter,
   return storeOp;
 }
 
+// This helper function implements the functionality of "promoting"
+// non-CPTR arguments of use_device_ptr to use_device_addr
+// arguments (automagic conversion of use_device_ptr ->
+// use_device_addr in these cases). The way we do so currently is
+// through the shuffling of operands from the devicePtrOperands to
+// deviceAddrOperands where neccesary and re-organizing the types,
+// locations and symbols to maintain the correct ordering of ptr/addr
+// input -> BlockArg.
+//
+// This effectively implements some deprecated OpenMP functionality
+// that some legacy applications unfortunately depend on
+// (deprecated in specification version 5.2):
+//
+// "If a list item in a use_device_ptr clause is not of type C_PTR,
+//  the behavior is as if the list item appeared in a use_device_addr
+//  clause. Support for such list items in a use_device_ptr clause
+//  is deprecated."
+static void promoteNonCPtrUseDevicePtrArgsToUseDeviceAddr(
+    mlir::omp::UseDeviceClauseOps &clauseOps,
+    llvm::SmallVectorImpl<mlir::Type> &useDeviceTypes,
+    llvm::SmallVectorImpl<mlir::Location> &useDeviceLocs,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *>
+        &useDeviceSymbols) {
+  auto moveElementToBack = [](size_t idx, auto &vector) {
+    auto *iter = std::next(vector.begin(), idx);
+    vector.push_back(*iter);
+    vector.erase(iter);
+  };
+
+  // Iterate over our use_device_ptr list and shift all non-cptr arguments into
+  // use_device_addr.
+  for (auto *it = clauseOps.useDevicePtrVars.begin();
+       it != clauseOps.useDevicePtrVars.end();) {
+    if (!fir::isa_builtin_cptr_type(fir::unwrapRefType(it->getType()))) {
+      clauseOps.useDeviceAddrVars.push_back(*it);
+      // We have to shuffle the symbols around as well, to maintain
+      // the correct Input -> BlockArg for use_device_ptr/use_device_addr.
+      // NOTE: However, as map's do not seem to be included currently
+      // this isn't as pertinent, but we must try to maintain for
+      // future alterations. I believe the reason they are not currently
+      // is that the BlockArg assign/lowering needs to be extended
+      // to a greater set of types.
+      auto idx = std::distance(clauseOps.useDevicePtrVars.begin(), it);
+      moveElementToBack(idx, useDeviceTypes);
+      moveElementToBack(idx, useDeviceLocs);
+      moveElementToBack(idx, useDeviceSymbols);
+      it = clauseOps.useDevicePtrVars.erase(it);
+      continue;
+    }
+    ++it;
+  }
+}
+
+/// Extract the list of function and variable symbols affected by the given
+/// 'declare target' directive and return the intended device type for them.
+static void getDeclareTargetInfo(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::pft::Evaluation &eval,
+    const Fortran::parser::OpenMPDeclareTargetConstruct &declareTargetConstruct,
+    mlir::omp::DeclareTargetClauseOps &clauseOps,
+    llvm::SmallVectorImpl<DeclareTargetCapturePair> &symbolAndClause) {
+  const auto &spec = std::get<Fortran::parser::OmpDeclareTargetSpecifier>(
+      declareTargetConstruct.t);
+  if (const auto *objectList{
+          Fortran::parser::Unwrap<Fortran::parser::OmpObjectList>(spec.u)}) {
+    ObjectList objects{makeObjects(*objectList, semaCtx)};
+    // Case: declare target(func, var1, var2)
+    gatherFuncAndVarSyms(objects, mlir::omp::DeclareTargetCaptureClause::to,
+                         symbolAndClause);
+  } else if (const auto *clauseList{
+                 Fortran::parser::Unwrap<Fortran::parser::OmpClauseList>(
+                     spec.u)}) {
+    if (clauseList->v.empty()) {
+      // Case: declare target, implicit capture of function
+      symbolAndClause.emplace_back(
+          mlir::omp::DeclareTargetCaptureClause::to,
+          eval.getOwningProcedure()->getSubprogramSymbol());
+    }
+
+    ClauseProcessor cp(converter, semaCtx, *clauseList);
+    cp.processDeviceType(clauseOps);
+    cp.processEnter(symbolAndClause);
+    cp.processLink(symbolAndClause);
+    cp.processTo(symbolAndClause);
+
+    cp.processTODO<clause::Indirect>(converter.getCurrentLocation(),
+                                     llvm::omp::Directive::OMPD_declare_target);
+  }
+}
+
+static void collectDeferredDeclareTargets(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::pft::Evaluation &eval,
+    const Fortran::parser::OpenMPDeclareTargetConstruct &declareTargetConstruct,
+    llvm::SmallVectorImpl<Fortran::lower::OMPDeferredDeclareTargetInfo>
+        &deferredDeclareTarget) {
+  mlir::omp::DeclareTargetClauseOps clauseOps;
+  llvm::SmallVector<DeclareTargetCapturePair> symbolAndClause;
+  getDeclareTargetInfo(converter, semaCtx, eval, declareTargetConstruct,
+                       clauseOps, symbolAndClause);
+  // Return the device type only if at least one of the targets for the
+  // directive is a function or subroutine
+  mlir::ModuleOp mod = converter.getFirOpBuilder().getModule();
+
+  for (const DeclareTargetCapturePair &symClause : symbolAndClause) {
+    mlir::Operation *op = mod.lookupSymbol(converter.mangleName(
+        std::get<const Fortran::semantics::Symbol &>(symClause)));
+
+    if (!op) {
+      deferredDeclareTarget.push_back({std::get<0>(symClause),
+                                       clauseOps.deviceType,
+                                       std::get<1>(symClause)});
+    }
+  }
+}
+
+static std::optional<mlir::omp::DeclareTargetDeviceType>
+getDeclareTargetFunctionDevice(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::pft::Evaluation &eval,
+    const Fortran::parser::OpenMPDeclareTargetConstruct
+        &declareTargetConstruct) {
+  mlir::omp::DeclareTargetClauseOps clauseOps;
+  llvm::SmallVector<DeclareTargetCapturePair> symbolAndClause;
+  getDeclareTargetInfo(converter, semaCtx, eval, declareTargetConstruct,
+                       clauseOps, symbolAndClause);
+
+  // Return the device type only if at least one of the targets for the
+  // directive is a function or subroutine
+  mlir::ModuleOp mod = converter.getFirOpBuilder().getModule();
+  for (const DeclareTargetCapturePair &symClause : symbolAndClause) {
+    mlir::Operation *op = mod.lookupSymbol(converter.mangleName(
+        std::get<const Fortran::semantics::Symbol &>(symClause)));
+
+    if (mlir::isa_and_nonnull<mlir::func::FuncOp>(op))
+      return clauseOps.deviceType;
+  }
+
+  return std::nullopt;
+}
+
+static llvm::SmallVector<const Fortran::semantics::Symbol *>
+genLoopVars(mlir::Operation *op, Fortran::lower::AbstractConverter &converter,
+            mlir::Location &loc,
+            llvm::ArrayRef<const Fortran::semantics::Symbol *> args) {
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+  auto &region = op->getRegion(0);
+
+  std::size_t loopVarTypeSize = 0;
+  for (const Fortran::semantics::Symbol *arg : args)
+    loopVarTypeSize = std::max(loopVarTypeSize, arg->GetUltimate().size());
+  mlir::Type loopVarType = getLoopVarType(converter, loopVarTypeSize);
+  llvm::SmallVector<mlir::Type> tiv(args.size(), loopVarType);
+  llvm::SmallVector<mlir::Location> locs(args.size(), loc);
+  firOpBuilder.createBlock(&region, {}, tiv, locs);
+  // The argument is not currently in memory, so make a temporary for the
+  // argument, and store it there, then bind that location to the argument.
+  mlir::Operation *storeOp = nullptr;
+  for (auto [argIndex, argSymbol] : llvm::enumerate(args)) {
+    mlir::Value indexVal = fir::getBase(region.front().getArgument(argIndex));
+    storeOp =
+        createAndSetPrivatizedLoopVar(converter, loc, indexVal, argSymbol);
+  }
+  firOpBuilder.setInsertionPointAfter(storeOp);
+  return llvm::SmallVector<const Fortran::semantics::Symbol *>(args);
+}
+
+static void genReductionVars(
+    mlir::Operation *op, Fortran::lower::AbstractConverter &converter,
+    mlir::Location &loc,
+    llvm::ArrayRef<const Fortran::semantics::Symbol *> reductionArgs,
+    llvm::ArrayRef<mlir::Type> reductionTypes) {
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+  llvm::SmallVector<mlir::Location> blockArgLocs(reductionArgs.size(), loc);
+
+  mlir::Block *entryBlock = firOpBuilder.createBlock(
+      &op->getRegion(0), {}, reductionTypes, blockArgLocs);
+
+  // Bind the reduction arguments to their block arguments.
+  for (auto [arg, prv] :
+       llvm::zip_equal(reductionArgs, entryBlock->getArguments())) {
+    converter.bindSymbol(*arg, prv);
+  }
+}
+
+static llvm::SmallVector<const Fortran::semantics::Symbol *>
+genLoopAndReductionVars(
+    mlir::Operation *op, Fortran::lower::AbstractConverter &converter,
+    mlir::Location &loc,
+    llvm::ArrayRef<const Fortran::semantics::Symbol *> loopArgs,
+    llvm::ArrayRef<const Fortran::semantics::Symbol *> reductionArgs,
+    llvm::ArrayRef<mlir::Type> reductionTypes) {
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+
+  llvm::SmallVector<mlir::Type> blockArgTypes;
+  llvm::SmallVector<mlir::Location> blockArgLocs;
+  blockArgTypes.reserve(loopArgs.size() + reductionArgs.size());
+  blockArgLocs.reserve(blockArgTypes.size());
+  mlir::Block *entryBlock;
+
+  if (loopArgs.size()) {
+    std::size_t loopVarTypeSize = 0;
+    for (const Fortran::semantics::Symbol *arg : loopArgs)
+      loopVarTypeSize = std::max(loopVarTypeSize, arg->GetUltimate().size());
+    mlir::Type loopVarType = getLoopVarType(converter, loopVarTypeSize);
+    std::fill_n(std::back_inserter(blockArgTypes), loopArgs.size(),
+                loopVarType);
+    std::fill_n(std::back_inserter(blockArgLocs), loopArgs.size(), loc);
+  }
+  if (reductionArgs.size()) {
+    llvm::copy(reductionTypes, std::back_inserter(blockArgTypes));
+    std::fill_n(std::back_inserter(blockArgLocs), reductionArgs.size(), loc);
+  }
+  entryBlock = firOpBuilder.createBlock(&op->getRegion(0), {}, blockArgTypes,
+                                        blockArgLocs);
+  // The argument is not currently in memory, so make a temporary for the
+  // argument, and store it there, then bind that location to the argument.
+  if (loopArgs.size()) {
+    mlir::Operation *storeOp = nullptr;
+    for (auto [argIndex, argSymbol] : llvm::enumerate(loopArgs)) {
+      mlir::Value indexVal =
+          fir::getBase(op->getRegion(0).front().getArgument(argIndex));
+      storeOp =
+          createAndSetPrivatizedLoopVar(converter, loc, indexVal, argSymbol);
+    }
+    firOpBuilder.setInsertionPointAfter(storeOp);
+  }
+  // Bind the reduction arguments to their block arguments
+  for (auto [arg, prv] : llvm::zip_equal(
+           reductionArgs,
+           llvm::drop_begin(entryBlock->getArguments(), loopArgs.size()))) {
+    converter.bindSymbol(*arg, prv);
+  }
+
+  return llvm::SmallVector<const Fortran::semantics::Symbol *>(loopArgs);
+}
+
+static void
+markDeclareTarget(mlir::Operation *op,
+                  Fortran::lower::AbstractConverter &converter,
+                  mlir::omp::DeclareTargetCaptureClause captureClause,
+                  mlir::omp::DeclareTargetDeviceType deviceType) {
+  // TODO: Add support for program local variables with declare target applied
+  auto declareTargetOp = llvm::dyn_cast<mlir::omp::DeclareTargetInterface>(op);
+  if (!declareTargetOp)
+    fir::emitFatalError(
+        converter.getCurrentLocation(),
+        "Attempt to apply declare target on unsupported operation");
+
+  // The function or global already has a declare target applied to it, very
+  // likely through implicit capture (usage in another declare target
+  // function/subroutine). It should be marked as any if it has been assigned
+  // both host and nohost, else we skip, as there is no change
+  if (declareTargetOp.isDeclareTarget()) {
+    if (declareTargetOp.getDeclareTargetDeviceType() != deviceType)
+      declareTargetOp.setDeclareTarget(mlir::omp::DeclareTargetDeviceType::any,
+                                       captureClause);
+    return;
+  }
+
+  declareTargetOp.setDeclareTarget(deviceType, captureClause);
+}
+
+//===----------------------------------------------------------------------===//
+// Op body generation helper structures and functions
+//===----------------------------------------------------------------------===//
+
 struct OpWithBodyGenInfo {
   /// A type for a code-gen callback function. This takes as argument the op for
   /// which the code is being generated and returns the arguments of the op's
@@ -493,362 +763,6 @@ static void genBodyOfTargetDataOp(
     genNestedEvaluations(converter, eval);
 }
 
-template <typename OpTy, typename... Args>
-static OpTy genOpWithBody(OpWithBodyGenInfo &info, Args &&...args) {
-  auto op = info.converter.getFirOpBuilder().create<OpTy>(
-      info.loc, std::forward<Args>(args)...);
-  createBodyOfOp<OpTy>(op, info);
-  return op;
-}
-
-static mlir::omp::MasterOp
-genMasterOp(Fortran::lower::AbstractConverter &converter,
-            Fortran::semantics::SemanticsContext &semaCtx,
-            Fortran::lower::pft::Evaluation &eval, bool genNested,
-            mlir::Location currentLocation) {
-  return genOpWithBody<mlir::omp::MasterOp>(
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(genNested));
-}
-
-static mlir::omp::OrderedRegionOp
-genOrderedRegionOp(Fortran::lower::AbstractConverter &converter,
-                   Fortran::semantics::SemanticsContext &semaCtx,
-                   Fortran::lower::pft::Evaluation &eval, bool genNested,
-                   mlir::Location currentLocation,
-                   const Fortran::parser::OmpClauseList &clauseList) {
-  mlir::omp::OrderedRegionClauseOps clauseOps;
-
-  ClauseProcessor cp(converter, semaCtx, clauseList);
-  cp.processTODO<clause::Simd>(currentLocation,
-                               llvm::omp::Directive::OMPD_ordered);
-
-  return genOpWithBody<mlir::omp::OrderedRegionOp>(
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(genNested),
-      clauseOps);
-}
-
-static mlir::omp::ParallelOp
-genParallelOp(Fortran::lower::AbstractConverter &converter,
-              Fortran::lower::SymMap &symTable,
-              Fortran::semantics::SemanticsContext &semaCtx,
-              Fortran::lower::pft::Evaluation &eval, bool genNested,
-              mlir::Location currentLocation,
-              const Fortran::parser::OmpClauseList &clauseList,
-              bool outerCombined = false) {
-  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
-  Fortran::lower::StatementContext stmtCtx;
-  mlir::omp::ParallelClauseOps clauseOps;
-  llvm::SmallVector<const Fortran::semantics::Symbol *> privateSyms;
-  llvm::SmallVector<mlir::Type> reductionTypes;
-  llvm::SmallVector<const Fortran::semantics::Symbol *> reductionSyms;
-
-  ClauseProcessor cp(converter, semaCtx, clauseList);
-  cp.processIf(llvm::omp::Directive::OMPD_parallel, clauseOps);
-  cp.processNumThreads(stmtCtx, clauseOps);
-  cp.processProcBind(clauseOps);
-  cp.processDefault();
-  cp.processAllocate(clauseOps);
-
-  if (!outerCombined)
-    cp.processReduction(currentLocation, clauseOps, &reductionTypes,
-                        &reductionSyms);
-
-  if (ReductionProcessor::doReductionByRef(clauseOps.reductionVars))
-    clauseOps.reductionByRefAttr = firOpBuilder.getUnitAttr();
-
-  auto reductionCallback = [&](mlir::Operation *op) {
-    llvm::SmallVector<mlir::Location> locs(clauseOps.reductionVars.size(),
-                                           currentLocation);
-    auto *block =
-        firOpBuilder.createBlock(&op->getRegion(0), {}, reductionTypes, locs);
-    for (auto [arg, prv] :
-         llvm::zip_equal(reductionSyms, block->getArguments())) {
-      converter.bindSymbol(*arg, prv);
-    }
-    return reductionSyms;
-  };
-
-  OpWithBodyGenInfo genInfo =
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(genNested)
-          .setOuterCombined(outerCombined)
-          .setClauses(&clauseList)
-          .setReductions(&reductionSyms, &reductionTypes)
-          .setGenRegionEntryCb(reductionCallback);
-
-  if (!enableDelayedPrivatization)
-    return genOpWithBody<mlir::omp::ParallelOp>(genInfo, clauseOps);
-
-  bool privatize = !outerCombined;
-  DataSharingProcessor dsp(converter, semaCtx, clauseList, eval,
-                           /*useDelayedPrivatization=*/true, &symTable);
-
-  if (privatize)
-    dsp.processStep1(&clauseOps, &privateSyms);
-
-  auto genRegionEntryCB = [&](mlir::Operation *op) {
-    auto parallelOp = llvm::cast<mlir::omp::ParallelOp>(op);
-
-    llvm::SmallVector<mlir::Location> reductionLocs(
-        clauseOps.reductionVars.size(), currentLocation);
-
-    mlir::OperandRange privateVars = parallelOp.getPrivateVars();
-    mlir::Region &region = parallelOp.getRegion();
-
-    llvm::SmallVector<mlir::Type> privateVarTypes = reductionTypes;
-    privateVarTypes.reserve(privateVarTypes.size() + privateVars.size());
-    llvm::transform(privateVars, std::back_inserter(privateVarTypes),
-                    [](mlir::Value v) { return v.getType(); });
-
-    llvm::SmallVector<mlir::Location> privateVarLocs = reductionLocs;
-    privateVarLocs.reserve(privateVarLocs.size() + privateVars.size());
-    llvm::transform(privateVars, std::back_inserter(privateVarLocs),
-                    [](mlir::Value v) { return v.getLoc(); });
-
-    firOpBuilder.createBlock(&region, /*insertPt=*/{}, privateVarTypes,
-                             privateVarLocs);
-
-    llvm::SmallVector<const Fortran::semantics::Symbol *> allSymbols =
-        reductionSyms;
-    allSymbols.append(privateSyms);
-    for (auto [arg, prv] : llvm::zip_equal(allSymbols, region.getArguments())) {
-      converter.bindSymbol(*arg, prv);
-    }
-
-    return allSymbols;
-  };
-
-  // TODO Merge with the reduction CB.
-  genInfo.setGenRegionEntryCb(genRegionEntryCB).setDataSharingProcessor(&dsp);
-  return genOpWithBody<mlir::omp::ParallelOp>(genInfo, clauseOps);
-}
-
-static mlir::omp::SectionOp
-genSectionOp(Fortran::lower::AbstractConverter &converter,
-             Fortran::semantics::SemanticsContext &semaCtx,
-             Fortran::lower::pft::Evaluation &eval, bool genNested,
-             mlir::Location currentLocation,
-             const Fortran::parser::OmpClauseList &sectionsClauseList) {
-  // Currently only private/firstprivate clause is handled, and
-  // all privatization is done within `omp.section` operations.
-  return genOpWithBody<mlir::omp::SectionOp>(
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(genNested)
-          .setClauses(&sectionsClauseList));
-}
-
-static mlir::omp::SingleOp
-genSingleOp(Fortran::lower::AbstractConverter &converter,
-            Fortran::semantics::SemanticsContext &semaCtx,
-            Fortran::lower::pft::Evaluation &eval, bool genNested,
-            mlir::Location currentLocation,
-            const Fortran::parser::OmpClauseList &beginClauseList,
-            const Fortran::parser::OmpClauseList &endClauseList) {
-  mlir::omp::SingleClauseOps clauseOps;
-
-  ClauseProcessor cp(converter, semaCtx, beginClauseList);
-  cp.processAllocate(clauseOps);
-  // TODO Support delayed privatization.
-
-  ClauseProcessor ecp(converter, semaCtx, endClauseList);
-  ecp.processNowait(clauseOps);
-  ecp.processCopyprivate(currentLocation, clauseOps);
-
-  return genOpWithBody<mlir::omp::SingleOp>(
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(genNested)
-          .setClauses(&beginClauseList),
-      clauseOps);
-}
-
-static mlir::omp::TaskOp
-genTaskOp(Fortran::lower::AbstractConverter &converter,
-          Fortran::semantics::SemanticsContext &semaCtx,
-          Fortran::lower::pft::Evaluation &eval, bool genNested,
-          mlir::Location currentLocation,
-          const Fortran::parser::OmpClauseList &clauseList) {
-  Fortran::lower::StatementContext stmtCtx;
-  mlir::omp::TaskClauseOps clauseOps;
-
-  ClauseProcessor cp(converter, semaCtx, clauseList);
-  cp.processIf(llvm::omp::Directive::OMPD_task, clauseOps);
-  cp.processAllocate(clauseOps);
-  cp.processDefault();
-  cp.processFinal(stmtCtx, clauseOps);
-  cp.processUntied(clauseOps);
-  cp.processMergeable(clauseOps);
-  cp.processPriority(stmtCtx, clauseOps);
-  cp.processDepend(clauseOps);
-  // TODO Support delayed privatization.
-
-  cp.processTODO<clause::InReduction, clause::Detach, clause::Affinity>(
-      currentLocation, llvm::omp::Directive::OMPD_task);
-
-  return genOpWithBody<mlir::omp::TaskOp>(
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(genNested)
-          .setClauses(&clauseList),
-      clauseOps);
-}
-
-static mlir::omp::TaskgroupOp
-genTaskgroupOp(Fortran::lower::AbstractConverter &converter,
-               Fortran::semantics::SemanticsContext &semaCtx,
-               Fortran::lower::pft::Evaluation &eval, bool genNested,
-               mlir::Location currentLocation,
-               const Fortran::parser::OmpClauseList &clauseList) {
-  mlir::omp::TaskgroupClauseOps clauseOps;
-
-  ClauseProcessor cp(converter, semaCtx, clauseList);
-  cp.processAllocate(clauseOps);
-  cp.processTODO<clause::TaskReduction>(currentLocation,
-                                        llvm::omp::Directive::OMPD_taskgroup);
-
-  return genOpWithBody<mlir::omp::TaskgroupOp>(
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(genNested)
-          .setClauses(&clauseList),
-      clauseOps);
-}
-
-// This helper function implements the functionality of "promoting"
-// non-CPTR arguments of use_device_ptr to use_device_addr
-// arguments (automagic conversion of use_device_ptr ->
-// use_device_addr in these cases). The way we do so currently is
-// through the shuffling of operands from the devicePtrOperands to
-// deviceAddrOperands where neccesary and re-organizing the types,
-// locations and symbols to maintain the correct ordering of ptr/addr
-// input -> BlockArg.
-//
-// This effectively implements some deprecated OpenMP functionality
-// that some legacy applications unfortunately depend on
-// (deprecated in specification version 5.2):
-//
-// "If a list item in a use_device_ptr clause is not of type C_PTR,
-//  the behavior is as if the list item appeared in a use_device_addr
-//  clause. Support for such list items in a use_device_ptr clause
-//  is deprecated."
-static void promoteNonCPtrUseDevicePtrArgsToUseDeviceAddr(
-    mlir::omp::UseDeviceClauseOps &clauseOps,
-    llvm::SmallVectorImpl<mlir::Type> &useDeviceTypes,
-    llvm::SmallVectorImpl<mlir::Location> &useDeviceLocs,
-    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *>
-        &useDeviceSymbols) {
-  auto moveElementToBack = [](size_t idx, auto &vector) {
-    auto *iter = std::next(vector.begin(), idx);
-    vector.push_back(*iter);
-    vector.erase(iter);
-  };
-
-  // Iterate over our use_device_ptr list and shift all non-cptr arguments into
-  // use_device_addr.
-  for (auto *it = clauseOps.useDevicePtrVars.begin();
-       it != clauseOps.useDevicePtrVars.end();) {
-    if (!fir::isa_builtin_cptr_type(fir::unwrapRefType(it->getType()))) {
-      clauseOps.useDeviceAddrVars.push_back(*it);
-      // We have to shuffle the symbols around as well, to maintain
-      // the correct Input -> BlockArg for use_device_ptr/use_device_addr.
-      // NOTE: However, as map's do not seem to be included currently
-      // this isn't as pertinent, but we must try to maintain for
-      // future alterations. I believe the reason they are not currently
-      // is that the BlockArg assign/lowering needs to be extended
-      // to a greater set of types.
-      auto idx = std::distance(clauseOps.useDevicePtrVars.begin(), it);
-      moveElementToBack(idx, useDeviceTypes);
-      moveElementToBack(idx, useDeviceLocs);
-      moveElementToBack(idx, useDeviceSymbols);
-      it = clauseOps.useDevicePtrVars.erase(it);
-      continue;
-    }
-    ++it;
-  }
-}
-
-static mlir::omp::TargetDataOp
-genTargetDataOp(Fortran::lower::AbstractConverter &converter,
-                Fortran::semantics::SemanticsContext &semaCtx,
-                Fortran::lower::pft::Evaluation &eval, bool genNested,
-                mlir::Location currentLocation,
-                const Fortran::parser::OmpClauseList &clauseList) {
-  Fortran::lower::StatementContext stmtCtx;
-  mlir::omp::TargetDataClauseOps clauseOps;
-  llvm::SmallVector<mlir::Type> useDeviceTypes;
-  llvm::SmallVector<mlir::Location> useDeviceLocs;
-  llvm::SmallVector<const Fortran::semantics::Symbol *> useDeviceSyms;
-
-  ClauseProcessor cp(converter, semaCtx, clauseList);
-  cp.processIf(llvm::omp::Directive::OMPD_target_data, clauseOps);
-  cp.processDevice(stmtCtx, clauseOps);
-  cp.processUseDevicePtr(clauseOps, useDeviceTypes, useDeviceLocs,
-                         useDeviceSyms);
-  cp.processUseDeviceAddr(clauseOps, useDeviceTypes, useDeviceLocs,
-                          useDeviceSyms);
-
-  // This function implements the deprecated functionality of use_device_ptr
-  // that allows users to provide non-CPTR arguments to it with the caveat
-  // that the compiler will treat them as use_device_addr. A lot of legacy
-  // code may still depend on this functionality, so we should support it
-  // in some manner. We do so currently by simply shifting non-cptr operands
-  // from the use_device_ptr list into the front of the use_device_addr list
-  // whilst maintaining the ordering of useDeviceLocs, useDeviceSymbols and
-  // useDeviceTypes to use_device_ptr/use_device_addr input for BlockArg
-  // ordering.
-  // TODO: Perhaps create a user provideable compiler option that will
-  // re-introduce a hard-error rather than a warning in these cases.
-  promoteNonCPtrUseDevicePtrArgsToUseDeviceAddr(clauseOps, useDeviceTypes,
-                                                useDeviceLocs, useDeviceSyms);
-  cp.processMap(currentLocation, llvm::omp::Directive::OMPD_target_data,
-                stmtCtx, clauseOps);
-
-  auto dataOp = converter.getFirOpBuilder().create<mlir::omp::TargetDataOp>(
-      currentLocation, clauseOps);
-
-  genBodyOfTargetDataOp(converter, semaCtx, eval, genNested, dataOp,
-                        useDeviceTypes, useDeviceLocs, useDeviceSyms,
-                        currentLocation);
-  return dataOp;
-}
-
-template <typename OpTy>
-static OpTy genTargetEnterExitDataUpdateOp(
-    Fortran::lower::AbstractConverter &converter,
-    Fortran::semantics::SemanticsContext &semaCtx,
-    mlir::Location currentLocation,
-    const Fortran::parser::OmpClauseList &clauseList) {
-  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
-  Fortran::lower::StatementContext stmtCtx;
-  mlir::omp::TargetEnterExitUpdateDataClauseOps clauseOps;
-
-  // GCC 9.3.0 emits a (probably) bogus warning about an unused variable.
-  [[maybe_unused]] llvm::omp::Directive directive;
-  if constexpr (std::is_same_v<OpTy, mlir::omp::TargetEnterDataOp>) {
-    directive = llvm::omp::Directive::OMPD_target_enter_data;
-  } else if constexpr (std::is_same_v<OpTy, mlir::omp::TargetExitDataOp>) {
-    directive = llvm::omp::Directive::OMPD_target_exit_data;
-  } else if constexpr (std::is_same_v<OpTy, mlir::omp::TargetUpdateOp>) {
-    directive = llvm::omp::Directive::OMPD_target_update;
-  } else {
-    return nullptr;
-  }
-
-  ClauseProcessor cp(converter, semaCtx, clauseList);
-  cp.processIf(directive, clauseOps);
-  cp.processDevice(stmtCtx, clauseOps);
-  cp.processDepend(clauseOps);
-  cp.processNowait(clauseOps);
-
-  if constexpr (std::is_same_v<OpTy, mlir::omp::TargetUpdateOp>) {
-    cp.processMotionClauses<clause::To>(stmtCtx, clauseOps);
-    cp.processMotionClauses<clause::From>(stmtCtx, clauseOps);
-  } else {
-    cp.processMap(currentLocation, directive, stmtCtx, clauseOps);
-  }
-
-  return firOpBuilder.create<OpTy>(currentLocation, clauseOps);
-}
-
 // This functions creates a block for the body of the targetOp's region. It adds
 // all the symbols present in mapSymbols as block arguments to this block.
 static void
@@ -1003,38 +917,583 @@ genBodyOfTargetOp(Fortran::lower::AbstractConverter &converter,
     genNestedEvaluations(converter, eval);
 }
 
+template <typename OpTy, typename... Args>
+static OpTy genOpWithBody(OpWithBodyGenInfo &info, Args &&...args) {
+  auto op = info.converter.getFirOpBuilder().create<OpTy>(
+      info.loc, std::forward<Args>(args)...);
+  createBodyOfOp<OpTy>(op, info);
+  return op;
+}
+
+//===----------------------------------------------------------------------===//
+// Code generation functions for clauses
+//===----------------------------------------------------------------------===//
+
+static void genCriticalDeclareClauses(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    const Fortran::parser::OmpClauseList &clauses, mlir::Location loc,
+    mlir::omp::CriticalClauseOps &clauseOps, llvm::StringRef name) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processHint(clauseOps);
+  clauseOps.nameAttr =
+      mlir::StringAttr::get(converter.getFirOpBuilder().getContext(), name);
+}
+
+static void genFlushClauses(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    const std::optional<Fortran::parser::OmpObjectList> &objects,
+    const std::optional<std::list<Fortran::parser::OmpMemoryOrderClause>>
+        &clauses,
+    mlir::Location loc, llvm::SmallVectorImpl<mlir::Value> &operandRange) {
+  if (objects)
+    genObjectList2(*objects, converter, operandRange);
+
+  if (clauses && clauses->size() > 0)
+    TODO(converter.getCurrentLocation(), "Handle OmpMemoryOrderClause");
+}
+
+static void
+genOrderedRegionClauses(Fortran::lower::AbstractConverter &converter,
+                        Fortran::semantics::SemanticsContext &semaCtx,
+                        const Fortran::parser::OmpClauseList &clauses,
+                        mlir::Location loc,
+                        mlir::omp::OrderedRegionClauseOps &clauseOps) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processTODO<clause::Simd>(loc, llvm::omp::Directive::OMPD_ordered);
+}
+
+static void genParallelClauses(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::StatementContext &stmtCtx,
+    const Fortran::parser::OmpClauseList &clauses, mlir::Location loc,
+    bool processReduction, mlir::omp::ParallelClauseOps &clauseOps,
+    llvm::SmallVectorImpl<mlir::Type> &reductionTypes,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> &reductionSyms) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processAllocate(clauseOps);
+  cp.processDefault();
+  cp.processIf(llvm::omp::Directive::OMPD_parallel, clauseOps);
+  cp.processNumThreads(stmtCtx, clauseOps);
+  cp.processProcBind(clauseOps);
+
+  if (processReduction) {
+    cp.processReduction(loc, clauseOps, &reductionTypes, &reductionSyms);
+    if (ReductionProcessor::doReductionByRef(clauseOps.reductionVars))
+      clauseOps.reductionByRefAttr = converter.getFirOpBuilder().getUnitAttr();
+  }
+}
+
+static void genSectionsClauses(Fortran::lower::AbstractConverter &converter,
+                               Fortran::semantics::SemanticsContext &semaCtx,
+                               const Fortran::parser::OmpClauseList &clauses,
+                               mlir::Location loc,
+                               bool clausesFromBeginSections,
+                               mlir::omp::SectionsClauseOps &clauseOps) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  if (clausesFromBeginSections) {
+    cp.processAllocate(clauseOps);
+    cp.processSectionsReduction(loc, clauseOps);
+    // TODO Support delayed privatization.
+  } else {
+    cp.processNowait(clauseOps);
+  }
+}
+
+static void genSimdLoopClauses(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::StatementContext &stmtCtx,
+    Fortran::lower::pft::Evaluation &eval,
+    const Fortran::parser::OmpClauseList &clauses, mlir::Location loc,
+    mlir::omp::SimdLoopClauseOps &clauseOps,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> &iv) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processCollapse(loc, eval, clauseOps, iv);
+  cp.processIf(llvm::omp::Directive::OMPD_simd, clauseOps);
+  cp.processReduction(loc, clauseOps);
+  cp.processSafelen(clauseOps);
+  cp.processSimdlen(clauseOps);
+  clauseOps.loopInclusiveAttr = converter.getFirOpBuilder().getUnitAttr();
+  // TODO Support delayed privatization.
+
+  cp.processTODO<clause::Aligned, clause::Allocate, clause::Linear,
+                 clause::Nontemporal, clause::Order>(
+      loc, llvm::omp::Directive::OMPD_simd);
+}
+
+static void genSingleClauses(Fortran::lower::AbstractConverter &converter,
+                             Fortran::semantics::SemanticsContext &semaCtx,
+                             const Fortran::parser::OmpClauseList &beginClauses,
+                             const Fortran::parser::OmpClauseList &endClauses,
+                             mlir::Location loc,
+                             mlir::omp::SingleClauseOps &clauseOps) {
+  ClauseProcessor bcp(converter, semaCtx, beginClauses);
+  bcp.processAllocate(clauseOps);
+  // TODO Support delayed privatization.
+
+  ClauseProcessor ecp(converter, semaCtx, endClauses);
+  ecp.processCopyprivate(loc, clauseOps);
+  ecp.processNowait(clauseOps);
+}
+
+static void genTargetClauses(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::StatementContext &stmtCtx,
+    const Fortran::parser::OmpClauseList &clauses, mlir::Location loc,
+    bool processHostOnlyClauses, bool processReduction,
+    mlir::omp::TargetClauseOps &clauseOps,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> &mapSyms,
+    llvm::SmallVectorImpl<mlir::Location> &mapLocs,
+    llvm::SmallVectorImpl<mlir::Type> &mapTypes,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> &deviceAddrSyms,
+    llvm::SmallVectorImpl<mlir::Location> &deviceAddrLocs,
+    llvm::SmallVectorImpl<mlir::Type> &deviceAddrTypes,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> &devicePtrSyms,
+    llvm::SmallVectorImpl<mlir::Location> &devicePtrLocs,
+    llvm::SmallVectorImpl<mlir::Type> &devicePtrTypes) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processDepend(clauseOps);
+  cp.processDevice(stmtCtx, clauseOps);
+  cp.processHasDeviceAddr(clauseOps, deviceAddrTypes, deviceAddrLocs,
+                          deviceAddrSyms);
+  cp.processIf(llvm::omp::Directive::OMPD_target, clauseOps);
+  cp.processIsDevicePtr(clauseOps, devicePtrTypes, devicePtrLocs,
+                        devicePtrSyms);
+  cp.processMap(loc, stmtCtx, clauseOps, &mapSyms, &mapLocs, &mapTypes);
+  cp.processThreadLimit(stmtCtx, clauseOps);
+  // TODO Support delayed privatization.
+
+  if (processHostOnlyClauses)
+    cp.processNowait(clauseOps);
+
+  cp.processTODO<clause::Allocate, clause::Defaultmap, clause::Firstprivate,
+                 clause::InReduction, clause::Private, clause::Reduction,
+                 clause::UsesAllocators>(loc,
+                                         llvm::omp::Directive::OMPD_target);
+}
+
+static void genTargetDataClauses(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::StatementContext &stmtCtx,
+    const Fortran::parser::OmpClauseList &clauses, mlir::Location loc,
+    mlir::omp::TargetDataClauseOps &clauseOps,
+    llvm::SmallVectorImpl<mlir::Type> &useDeviceTypes,
+    llvm::SmallVectorImpl<mlir::Location> &useDeviceLocs,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> &useDeviceSyms) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processDevice(stmtCtx, clauseOps);
+  cp.processIf(llvm::omp::Directive::OMPD_target_data, clauseOps);
+  cp.processMap(loc, stmtCtx, clauseOps);
+  cp.processUseDeviceAddr(clauseOps, useDeviceTypes, useDeviceLocs,
+                          useDeviceSyms);
+  cp.processUseDevicePtr(clauseOps, useDeviceTypes, useDeviceLocs,
+                         useDeviceSyms);
+
+  // This function implements the deprecated functionality of use_device_ptr
+  // that allows users to provide non-CPTR arguments to it with the caveat
+  // that the compiler will treat them as use_device_addr. A lot of legacy
+  // code may still depend on this functionality, so we should support it
+  // in some manner. We do so currently by simply shifting non-cptr operands
+  // from the use_device_ptr list into the front of the use_device_addr list
+  // whilst maintaining the ordering of useDeviceLocs, useDeviceSyms and
+  // useDeviceTypes to use_device_ptr/use_device_addr input for BlockArg
+  // ordering.
+  // TODO: Perhaps create a user provideable compiler option that will
+  // re-introduce a hard-error rather than a warning in these cases.
+  promoteNonCPtrUseDevicePtrArgsToUseDeviceAddr(clauseOps, useDeviceTypes,
+                                                useDeviceLocs, useDeviceSyms);
+}
+
+static void genTargetEnterExitUpdateDataClauses(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::StatementContext &stmtCtx,
+    const Fortran::parser::OmpClauseList &clauses, mlir::Location loc,
+    llvm::omp::Directive directive,
+    mlir::omp::TargetEnterExitUpdateDataClauseOps &clauseOps) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processDepend(clauseOps);
+  cp.processDevice(stmtCtx, clauseOps);
+  cp.processIf(directive, clauseOps);
+  cp.processNowait(clauseOps);
+
+  if (directive == llvm::omp::Directive::OMPD_target_update) {
+    cp.processMotionClauses<clause::To>(stmtCtx, clauseOps);
+    cp.processMotionClauses<clause::From>(stmtCtx, clauseOps);
+  } else {
+    cp.processMap(loc, stmtCtx, clauseOps);
+  }
+}
+
+static void genTaskClauses(Fortran::lower::AbstractConverter &converter,
+                           Fortran::semantics::SemanticsContext &semaCtx,
+                           Fortran::lower::StatementContext &stmtCtx,
+                           const Fortran::parser::OmpClauseList &clauses,
+                           mlir::Location loc,
+                           mlir::omp::TaskClauseOps &clauseOps) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processAllocate(clauseOps);
+  cp.processDefault();
+  cp.processDepend(clauseOps);
+  cp.processFinal(stmtCtx, clauseOps);
+  cp.processIf(llvm::omp::Directive::OMPD_task, clauseOps);
+  cp.processMergeable(clauseOps);
+  cp.processPriority(stmtCtx, clauseOps);
+  cp.processUntied(clauseOps);
+  // TODO Support delayed privatization.
+
+  cp.processTODO<clause::Affinity, clause::Detach, clause::InReduction>(
+      loc, llvm::omp::Directive::OMPD_task);
+}
+
+static void genTaskgroupClauses(Fortran::lower::AbstractConverter &converter,
+                                Fortran::semantics::SemanticsContext &semaCtx,
+                                const Fortran::parser::OmpClauseList &clauses,
+                                mlir::Location loc,
+                                mlir::omp::TaskgroupClauseOps &clauseOps) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processAllocate(clauseOps);
+
+  cp.processTODO<clause::TaskReduction>(loc,
+                                        llvm::omp::Directive::OMPD_taskgroup);
+}
+
+static void genTaskwaitClauses(Fortran::lower::AbstractConverter &converter,
+                               Fortran::semantics::SemanticsContext &semaCtx,
+                               const Fortran::parser::OmpClauseList &clauses,
+                               mlir::Location loc,
+                               mlir::omp::TaskwaitClauseOps &clauseOps) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processTODO<clause::Depend, clause::Nowait>(
+      loc, llvm::omp::Directive::OMPD_taskwait);
+}
+
+static void genTeamsClauses(Fortran::lower::AbstractConverter &converter,
+                            Fortran::semantics::SemanticsContext &semaCtx,
+                            Fortran::lower::StatementContext &stmtCtx,
+                            const Fortran::parser::OmpClauseList &clauses,
+                            mlir::Location loc,
+                            mlir::omp::TeamsClauseOps &clauseOps) {
+  ClauseProcessor cp(converter, semaCtx, clauses);
+  cp.processAllocate(clauseOps);
+  cp.processDefault();
+  cp.processIf(llvm::omp::Directive::OMPD_teams, clauseOps);
+  cp.processNumTeams(stmtCtx, clauseOps);
+  cp.processThreadLimit(stmtCtx, clauseOps);
+  // TODO Support delayed privatization.
+
+  cp.processTODO<clause::Reduction>(loc, llvm::omp::Directive::OMPD_teams);
+}
+
+static void genWsloopClauses(
+    Fortran::lower::AbstractConverter &converter,
+    Fortran::semantics::SemanticsContext &semaCtx,
+    Fortran::lower::StatementContext &stmtCtx,
+    Fortran::lower::pft::Evaluation &eval,
+    const Fortran::parser::OmpClauseList &beginClauses,
+    const Fortran::parser::OmpClauseList *endClauses, mlir::Location loc,
+    mlir::omp::WsloopClauseOps &clauseOps,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> &iv,
+    llvm::SmallVectorImpl<mlir::Type> &reductionTypes,
+    llvm::SmallVectorImpl<const Fortran::semantics::Symbol *> &reductionSyms) {
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+  ClauseProcessor bcp(converter, semaCtx, beginClauses);
+  bcp.processCollapse(loc, eval, clauseOps, iv);
+  bcp.processOrdered(clauseOps);
+  bcp.processReduction(loc, clauseOps, &reductionTypes, &reductionSyms);
+  bcp.processSchedule(stmtCtx, clauseOps);
+  clauseOps.loopInclusiveAttr = firOpBuilder.getUnitAttr();
+  // TODO Support delayed privatization.
+
+  if (ReductionProcessor::doReductionByRef(clauseOps.reductionVars))
+    clauseOps.reductionByRefAttr = firOpBuilder.getUnitAttr();
+
+  if (endClauses) {
+    ClauseProcessor ecp(converter, semaCtx, *endClauses);
+    ecp.processNowait(clauseOps);
+  }
+
+  bcp.processTODO<clause::Allocate, clause::Linear, clause::Order>(
+      loc, llvm::omp::Directive::OMPD_do);
+}
+
+//===----------------------------------------------------------------------===//
+// Code generation functions for leaf constructs
+//===----------------------------------------------------------------------===//
+
+static mlir::omp::BarrierOp
+genBarrierOp(Fortran::lower::AbstractConverter &converter,
+             Fortran::semantics::SemanticsContext &semaCtx,
+             Fortran::lower::pft::Evaluation &eval, mlir::Location loc) {
+  return converter.getFirOpBuilder().create<mlir::omp::BarrierOp>(loc);
+}
+
+static mlir::omp::CriticalOp
+genCriticalOp(Fortran::lower::AbstractConverter &converter,
+              Fortran::semantics::SemanticsContext &semaCtx,
+              Fortran::lower::pft::Evaluation &eval, bool genNested,
+              mlir::Location loc,
+              const Fortran::parser::OmpClauseList &clauseList,
+              const std::optional<Fortran::parser::Name> &name) {
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+  mlir::FlatSymbolRefAttr nameAttr;
+
+  if (name) {
+    std::string nameStr = name->ToString();
+    mlir::ModuleOp mod = firOpBuilder.getModule();
+    auto global = mod.lookupSymbol<mlir::omp::CriticalDeclareOp>(nameStr);
+    if (!global) {
+      mlir::omp::CriticalClauseOps clauseOps;
+      genCriticalDeclareClauses(converter, semaCtx, clauseList, loc, clauseOps,
+                                nameStr);
+
+      mlir::OpBuilder modBuilder(mod.getBodyRegion());
+      global = modBuilder.create<mlir::omp::CriticalDeclareOp>(loc, clauseOps);
+    }
+    nameAttr = mlir::FlatSymbolRefAttr::get(firOpBuilder.getContext(),
+                                            global.getSymName());
+  }
+
+  return genOpWithBody<mlir::omp::CriticalOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval).setGenNested(genNested),
+      nameAttr);
+}
+
+static mlir::omp::DistributeOp
+genDistributeOp(Fortran::lower::AbstractConverter &converter,
+                Fortran::semantics::SemanticsContext &semaCtx,
+                Fortran::lower::pft::Evaluation &eval, bool genNested,
+                mlir::Location loc,
+                const Fortran::parser::OmpClauseList &clauseList) {
+  TODO(loc, "Distribute construct");
+  return nullptr;
+}
+
+static mlir::omp::FlushOp
+genFlushOp(Fortran::lower::AbstractConverter &converter,
+           Fortran::semantics::SemanticsContext &semaCtx,
+           Fortran::lower::pft::Evaluation &eval, mlir::Location loc,
+           const std::optional<Fortran::parser::OmpObjectList> &objectList,
+           const std::optional<std::list<Fortran::parser::OmpMemoryOrderClause>>
+               &clauseList) {
+  llvm::SmallVector<mlir::Value> operandRange;
+  genFlushClauses(converter, semaCtx, objectList, clauseList, loc,
+                  operandRange);
+
+  return converter.getFirOpBuilder().create<mlir::omp::FlushOp>(
+      converter.getCurrentLocation(), operandRange);
+}
+
+static mlir::omp::MasterOp
+genMasterOp(Fortran::lower::AbstractConverter &converter,
+            Fortran::semantics::SemanticsContext &semaCtx,
+            Fortran::lower::pft::Evaluation &eval, bool genNested,
+            mlir::Location loc) {
+  return genOpWithBody<mlir::omp::MasterOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval).setGenNested(genNested));
+}
+
+static mlir::omp::OrderedOp
+genOrderedOp(Fortran::lower::AbstractConverter &converter,
+             Fortran::semantics::SemanticsContext &semaCtx,
+             Fortran::lower::pft::Evaluation &eval, mlir::Location loc,
+             const Fortran::parser::OmpClauseList &clauseList) {
+  TODO(loc, "OMPD_ordered");
+  return nullptr;
+}
+
+static mlir::omp::OrderedRegionOp
+genOrderedRegionOp(Fortran::lower::AbstractConverter &converter,
+                   Fortran::semantics::SemanticsContext &semaCtx,
+                   Fortran::lower::pft::Evaluation &eval, bool genNested,
+                   mlir::Location loc,
+                   const Fortran::parser::OmpClauseList &clauseList) {
+  mlir::omp::OrderedRegionClauseOps clauseOps;
+  genOrderedRegionClauses(converter, semaCtx, clauseList, loc, clauseOps);
+
+  return genOpWithBody<mlir::omp::OrderedRegionOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval).setGenNested(genNested),
+      clauseOps);
+}
+
+static mlir::omp::ParallelOp
+genParallelOp(Fortran::lower::AbstractConverter &converter,
+              Fortran::lower::SymMap &symTable,
+              Fortran::semantics::SemanticsContext &semaCtx,
+              Fortran::lower::pft::Evaluation &eval, bool genNested,
+              mlir::Location loc,
+              const Fortran::parser::OmpClauseList &clauseList,
+              bool outerCombined = false) {
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+  Fortran::lower::StatementContext stmtCtx;
+  mlir::omp::ParallelClauseOps clauseOps;
+  llvm::SmallVector<const Fortran::semantics::Symbol *> privateSyms;
+  llvm::SmallVector<mlir::Type> reductionTypes;
+  llvm::SmallVector<const Fortran::semantics::Symbol *> reductionSyms;
+  genParallelClauses(converter, semaCtx, stmtCtx, clauseList, loc,
+                     /*processReduction=*/!outerCombined, clauseOps,
+                     reductionTypes, reductionSyms);
+
+  auto reductionCallback = [&](mlir::Operation *op) {
+    genReductionVars(op, converter, loc, reductionSyms, reductionTypes);
+    return reductionSyms;
+  };
+
+  OpWithBodyGenInfo genInfo =
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval)
+          .setGenNested(genNested)
+          .setOuterCombined(outerCombined)
+          .setClauses(&clauseList)
+          .setReductions(&reductionSyms, &reductionTypes)
+          .setGenRegionEntryCb(reductionCallback);
+
+  if (!enableDelayedPrivatization)
+    return genOpWithBody<mlir::omp::ParallelOp>(genInfo, clauseOps);
+
+  bool privatize = !outerCombined;
+  DataSharingProcessor dsp(converter, semaCtx, clauseList, eval,
+                           /*useDelayedPrivatization=*/true, &symTable);
+
+  if (privatize)
+    dsp.processStep1(&clauseOps, &privateSyms);
+
+  auto genRegionEntryCB = [&](mlir::Operation *op) {
+    auto parallelOp = llvm::cast<mlir::omp::ParallelOp>(op);
+
+    llvm::SmallVector<mlir::Location> reductionLocs(
+        clauseOps.reductionVars.size(), loc);
+
+    mlir::OperandRange privateVars = parallelOp.getPrivateVars();
+    mlir::Region &region = parallelOp.getRegion();
+
+    llvm::SmallVector<mlir::Type> privateVarTypes = reductionTypes;
+    privateVarTypes.reserve(privateVarTypes.size() + privateVars.size());
+    llvm::transform(privateVars, std::back_inserter(privateVarTypes),
+                    [](mlir::Value v) { return v.getType(); });
+
+    llvm::SmallVector<mlir::Location> privateVarLocs = reductionLocs;
+    privateVarLocs.reserve(privateVarLocs.size() + privateVars.size());
+    llvm::transform(privateVars, std::back_inserter(privateVarLocs),
+                    [](mlir::Value v) { return v.getLoc(); });
+
+    firOpBuilder.createBlock(&region, /*insertPt=*/{}, privateVarTypes,
+                             privateVarLocs);
+
+    llvm::SmallVector<const Fortran::semantics::Symbol *> allSymbols =
+        reductionSyms;
+    allSymbols.append(privateSyms);
+    for (auto [arg, prv] : llvm::zip_equal(allSymbols, region.getArguments())) {
+      converter.bindSymbol(*arg, prv);
+    }
+
+    return allSymbols;
+  };
+
+  // TODO Merge with the reduction CB.
+  genInfo.setGenRegionEntryCb(genRegionEntryCB).setDataSharingProcessor(&dsp);
+  return genOpWithBody<mlir::omp::ParallelOp>(genInfo, clauseOps);
+}
+
+static mlir::omp::SectionOp
+genSectionOp(Fortran::lower::AbstractConverter &converter,
+             Fortran::semantics::SemanticsContext &semaCtx,
+             Fortran::lower::pft::Evaluation &eval, bool genNested,
+             mlir::Location loc,
+             const Fortran::parser::OmpClauseList &clauseList) {
+  // Currently only private/firstprivate clause is handled, and
+  // all privatization is done within `omp.section` operations.
+  return genOpWithBody<mlir::omp::SectionOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval)
+          .setGenNested(genNested)
+          .setClauses(&clauseList));
+}
+
+static mlir::omp::SectionsOp
+genSectionsOp(Fortran::lower::AbstractConverter &converter,
+              Fortran::semantics::SemanticsContext &semaCtx,
+              Fortran::lower::pft::Evaluation &eval, mlir::Location loc,
+              const mlir::omp::SectionsClauseOps &clauseOps) {
+  return genOpWithBody<mlir::omp::SectionsOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval).setGenNested(false),
+      clauseOps);
+}
+
+static mlir::omp::SimdLoopOp
+genSimdLoopOp(Fortran::lower::AbstractConverter &converter,
+              Fortran::semantics::SemanticsContext &semaCtx,
+              Fortran::lower::pft::Evaluation &eval, mlir::Location loc,
+              const Fortran::parser::OmpClauseList &clauseList) {
+  DataSharingProcessor dsp(converter, semaCtx, clauseList, eval);
+  dsp.processStep1();
+
+  Fortran::lower::StatementContext stmtCtx;
+  mlir::omp::SimdLoopClauseOps clauseOps;
+  llvm::SmallVector<const Fortran::semantics::Symbol *> iv;
+  genSimdLoopClauses(converter, semaCtx, stmtCtx, eval, clauseList, loc,
+                     clauseOps, iv);
+
+  auto *nestedEval =
+      getCollapsedLoopEval(eval, Fortran::lower::getCollapseValue(clauseList));
+
+  auto ivCallback = [&](mlir::Operation *op) {
+    return genLoopVars(op, converter, loc, iv);
+  };
+
+  return genOpWithBody<mlir::omp::SimdLoopOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, *nestedEval)
+          .setClauses(&clauseList)
+          .setDataSharingProcessor(&dsp)
+          .setGenRegionEntryCb(ivCallback),
+      clauseOps);
+}
+
+static mlir::omp::SingleOp
+genSingleOp(Fortran::lower::AbstractConverter &converter,
+            Fortran::semantics::SemanticsContext &semaCtx,
+            Fortran::lower::pft::Evaluation &eval, bool genNested,
+            mlir::Location loc,
+            const Fortran::parser::OmpClauseList &beginClauseList,
+            const Fortran::parser::OmpClauseList &endClauseList) {
+  mlir::omp::SingleClauseOps clauseOps;
+  genSingleClauses(converter, semaCtx, beginClauseList, endClauseList, loc,
+                   clauseOps);
+
+  return genOpWithBody<mlir::omp::SingleOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval)
+          .setGenNested(genNested)
+          .setClauses(&beginClauseList),
+      clauseOps);
+}
+
 static mlir::omp::TargetOp
 genTargetOp(Fortran::lower::AbstractConverter &converter,
             Fortran::semantics::SemanticsContext &semaCtx,
             Fortran::lower::pft::Evaluation &eval, bool genNested,
-            mlir::Location currentLocation,
+            mlir::Location loc,
             const Fortran::parser::OmpClauseList &clauseList,
-            llvm::omp::Directive directive, bool outerCombined = false) {
+            bool outerCombined = false) {
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
   Fortran::lower::StatementContext stmtCtx;
+
+  bool processHostOnlyClauses =
+      !llvm::cast<mlir::omp::OffloadModuleInterface>(*converter.getModuleOp())
+           .getIsTargetDevice();
+
   mlir::omp::TargetClauseOps clauseOps;
-  llvm::SmallVector<mlir::Type> mapTypes, devicePtrTypes, deviceAddrTypes;
-  llvm::SmallVector<mlir::Location> mapLocs, devicePtrLocs, deviceAddrLocs;
   llvm::SmallVector<const Fortran::semantics::Symbol *> mapSyms, devicePtrSyms,
       deviceAddrSyms;
-
-  ClauseProcessor cp(converter, semaCtx, clauseList);
-  cp.processIf(llvm::omp::Directive::OMPD_target, clauseOps);
-  cp.processDevice(stmtCtx, clauseOps);
-  cp.processThreadLimit(stmtCtx, clauseOps);
-  cp.processDepend(clauseOps);
-  cp.processNowait(clauseOps);
-  cp.processMap(currentLocation, directive, stmtCtx, clauseOps, &mapSyms,
-                &mapLocs, &mapTypes);
-  cp.processIsDevicePtr(clauseOps, devicePtrTypes, devicePtrLocs,
-                        devicePtrSyms);
-  cp.processHasDeviceAddr(clauseOps, deviceAddrTypes, deviceAddrLocs,
-                          deviceAddrSyms);
-  // TODO Support delayed privatization.
-
-  cp.processTODO<clause::Private, clause::Firstprivate, clause::Reduction,
-                 clause::InReduction, clause::Allocate, clause::UsesAllocators,
-                 clause::Defaultmap>(currentLocation,
-                                     llvm::omp::Directive::OMPD_target);
+  llvm::SmallVector<mlir::Location> mapLocs, devicePtrLocs, deviceAddrLocs;
+  llvm::SmallVector<mlir::Type> mapTypes, devicePtrTypes, deviceAddrTypes;
+  genTargetClauses(converter, semaCtx, stmtCtx, clauseList, loc,
+                   processHostOnlyClauses, /*processReduction=*/outerCombined,
+                   clauseOps, mapSyms, mapLocs, mapTypes, deviceAddrSyms,
+                   deviceAddrLocs, deviceAddrTypes, devicePtrSyms,
+                   devicePtrLocs, devicePtrTypes);
 
   // 5.8.1 Implicit Data-Mapping Attribute Rules
   // The following code follows the implicit data-mapping rules to map all the
@@ -1056,22 +1515,21 @@ genTargetOp(Fortran::lower::AbstractConverter &converter,
         fir::ExtendedValue dataExv = converter.getSymbolExtendedValue(sym);
         name << sym.name().ToString();
 
-        Fortran::lower::AddrAndBoundsInfo info =
-            getDataOperandBaseAddr(converter, converter.getFirOpBuilder(), sym,
-                                   converter.getCurrentLocation());
+        Fortran::lower::AddrAndBoundsInfo info = getDataOperandBaseAddr(
+            converter, firOpBuilder, sym, converter.getCurrentLocation());
         if (fir::unwrapRefType(info.addr.getType()).isa<fir::BaseBoxType>())
           bounds =
               Fortran::lower::genBoundsOpsFromBox<mlir::omp::MapBoundsOp,
                                                   mlir::omp::MapBoundsType>(
-                  converter.getFirOpBuilder(), converter.getCurrentLocation(),
-                  converter, dataExv, info);
+                  firOpBuilder, converter.getCurrentLocation(), converter,
+                  dataExv, info);
         if (fir::unwrapRefType(info.addr.getType()).isa<fir::SequenceType>()) {
           bool dataExvIsAssumedSize =
               Fortran::semantics::IsAssumedSizeArray(sym.GetUltimate());
           bounds = Fortran::lower::genBaseBoundsOps<mlir::omp::MapBoundsOp,
                                                     mlir::omp::MapBoundsType>(
-              converter.getFirOpBuilder(), converter.getCurrentLocation(),
-              converter, dataExv, dataExvIsAssumedSize);
+              firOpBuilder, converter.getCurrentLocation(), converter, dataExv,
+              dataExvIsAssumedSize);
         }
 
         llvm::omp::OpenMPOffloadMappingFlags mapFlag =
@@ -1085,7 +1543,7 @@ genTargetOp(Fortran::lower::AbstractConverter &converter,
 
         // If a variable is specified in declare target link and if device
         // type is not specified as `nohost`, it needs to be mapped tofrom
-        mlir::ModuleOp mod = converter.getFirOpBuilder().getModule();
+        mlir::ModuleOp mod = firOpBuilder.getModule();
         mlir::Operation *op = mod.lookupSymbol(converter.mangleName(sym));
         auto declareTargetOp =
             llvm::dyn_cast_if_present<mlir::omp::DeclareTargetInterface>(op);
@@ -1105,8 +1563,8 @@ genTargetOp(Fortran::lower::AbstractConverter &converter,
         }
 
         mlir::Value mapOp = createMapInfoOp(
-            converter.getFirOpBuilder(), baseOp.getLoc(), baseOp, mlir::Value{},
-            name.str(), bounds, {},
+            firOpBuilder, baseOp.getLoc(), baseOp, mlir::Value{}, name.str(),
+            bounds, {},
             static_cast<
                 std::underlying_type_t<llvm::omp::OpenMPOffloadMappingFlags>>(
                 mapFlag),
@@ -1121,338 +1579,144 @@ genTargetOp(Fortran::lower::AbstractConverter &converter,
   };
   Fortran::lower::pft::visitAllSymbols(eval, captureImplicitMap);
 
-  auto targetOp = converter.getFirOpBuilder().create<mlir::omp::TargetOp>(
-      currentLocation, clauseOps);
-
+  auto targetOp = firOpBuilder.create<mlir::omp::TargetOp>(loc, clauseOps);
   genBodyOfTargetOp(converter, semaCtx, eval, genNested, targetOp, mapSyms,
-                    mapLocs, mapTypes, currentLocation);
-
+                    mapLocs, mapTypes, loc);
   return targetOp;
 }
 
-static mlir::omp::TeamsOp
-genTeamsOp(Fortran::lower::AbstractConverter &converter,
-           Fortran::semantics::SemanticsContext &semaCtx,
-           Fortran::lower::pft::Evaluation &eval, bool genNested,
-           mlir::Location currentLocation,
-           const Fortran::parser::OmpClauseList &clauseList,
-           bool outerCombined = false) {
+static mlir::omp::TargetDataOp
+genTargetDataOp(Fortran::lower::AbstractConverter &converter,
+                Fortran::semantics::SemanticsContext &semaCtx,
+                Fortran::lower::pft::Evaluation &eval, bool genNested,
+                mlir::Location loc,
+                const Fortran::parser::OmpClauseList &clauseList) {
   Fortran::lower::StatementContext stmtCtx;
-  mlir::omp::TeamsClauseOps clauseOps;
-
-  ClauseProcessor cp(converter, semaCtx, clauseList);
-  cp.processIf(llvm::omp::Directive::OMPD_teams, clauseOps);
-  cp.processAllocate(clauseOps);
-  cp.processDefault();
-  cp.processNumTeams(stmtCtx, clauseOps);
-  cp.processThreadLimit(stmtCtx, clauseOps);
-  // TODO Support delayed privatization.
-
-  cp.processTODO<clause::Reduction>(currentLocation,
-                                    llvm::omp::Directive::OMPD_teams);
-
-  return genOpWithBody<mlir::omp::TeamsOp>(
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(genNested)
-          .setOuterCombined(outerCombined)
-          .setClauses(&clauseList),
-      clauseOps);
+  mlir::omp::TargetDataClauseOps clauseOps;
+  llvm::SmallVector<mlir::Type> useDeviceTypes;
+  llvm::SmallVector<mlir::Location> useDeviceLocs;
+  llvm::SmallVector<const Fortran::semantics::Symbol *> useDeviceSyms;
+  genTargetDataClauses(converter, semaCtx, stmtCtx, clauseList, loc, clauseOps,
+                       useDeviceTypes, useDeviceLocs, useDeviceSyms);
+
+  auto targetDataOp =
+      converter.getFirOpBuilder().create<mlir::omp::TargetDataOp>(loc,
+                                                                  clauseOps);
+  genBodyOfTargetDataOp(converter, semaCtx, eval, genNested, targetDataOp,
+                        useDeviceTypes, useDeviceLocs, useDeviceSyms, loc);
+  return targetDataOp;
 }
 
-/// Extract the list of function and variable symbols affected by the given
-/// 'declare target' directive and return the intended device type for them.
-static void getDeclareTargetInfo(
+template <typename OpTy>
+static OpTy genTargetEnterExitUpdateDataOp(
     Fortran::lower::AbstractConverter &converter,
-    Fortran::semantics::SemanticsContext &semaCtx,
-    Fortran::lower::pft::Evaluation &eval,
-    const Fortran::parser::OpenMPDeclareTargetConstruct &declareTargetConstruct,
-    mlir::omp::DeclareTargetClauseOps &clauseOps,
-    llvm::SmallVectorImpl<DeclareTargetCapturePair> &symbolAndClause) {
-  const auto &spec = std::get<Fortran::parser::OmpDeclareTargetSpecifier>(
-      declareTargetConstruct.t);
-  if (const auto *objectList{
-          Fortran::parser::Unwrap<Fortran::parser::OmpObjectList>(spec.u)}) {
-    ObjectList objects{makeObjects(*objectList, semaCtx)};
-    // Case: declare target(func, var1, var2)
-    gatherFuncAndVarSyms(objects, mlir::omp::DeclareTargetCaptureClause::to,
-                         symbolAndClause);
-  } else if (const auto *clauseList{
-                 Fortran::parser::Unwrap<Fortran::parser::OmpClauseList>(
-                     spec.u)}) {
-    if (clauseList->v.empty()) {
-      // Case: declare target, implicit capture of function
-      symbolAndClause.emplace_back(
-          mlir::omp::DeclareTargetCaptureClause::to,
-          eval.getOwningProcedure()->getSubprogramSymbol());
-    }
+    Fortran::semantics::SemanticsContext &semaCtx, mlir::Location loc,
+    const Fortran::parser::OmpClauseList &clauseList) {
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+  Fortran::lower::StatementContext stmtCtx;
 
-    ClauseProcessor cp(converter, semaCtx, *clauseList);
-    cp.processTo(symbolAndClause);
-    cp.processEnter(symbolAndClause);
-    cp.processLink(symbolAndClause);
-    cp.processDeviceType(clauseOps);
-    cp.processTODO<clause::Indirect>(converter.getCurrentLocation(),
-                                     llvm::omp::Directive::OMPD_declare_target);
+  // GCC 9.3.0 emits a (probably) bogus warning about an unused variable.
+  [[maybe_unused]] llvm::omp::Directive directive;
+  if constexpr (std::is_same_v<OpTy, mlir::omp::TargetEnterDataOp>) {
+    directive = llvm::omp::Directive::OMPD_target_enter_data;
+  } else if constexpr (std::is_same_v<OpTy, mlir::omp::TargetExitDataOp>) {
+    directive = llvm::omp::Directive::OMPD_target_exit_data;
+  } else if constexpr (std::is_same_v<OpTy, mlir::omp::TargetUpdateOp>) {
+    directive = llvm::omp::Directive::OMPD_target_update;
+  } else {
+    llvm_unreachable("Unexpected TARGET DATA construct");
   }
-}
 
-static void collectDeferredDeclareTargets(
-    Fortran::lower::AbstractConverter &converter,
-    Fortran::semantics::SemanticsContext &semaCtx,
-    Fortran::lower::pft::Evaluation &eval,
-    const Fortran::parser::OpenMPDeclareTargetConstruct &declareTargetConstruct,
-    llvm::SmallVectorImpl<Fortran::lower::OMPDeferredDeclareTargetInfo>
-        &deferredDeclareTarget) {
-  mlir::omp::DeclareTargetClauseOps clauseOps;
-  llvm::SmallVector<DeclareTargetCapturePair> symbolAndClause;
-  getDeclareTargetInfo(converter, semaCtx, eval, declareTargetConstruct,
-                       clauseOps, symbolAndClause);
-  // Return the device type only if at least one of the targets for the
-  // directive is a function or subroutine
-  mlir::ModuleOp mod = converter.getFirOpBuilder().getModule();
-
-  for (const DeclareTargetCapturePair &symClause : symbolAndClause) {
-    mlir::Operation *op = mod.lookupSymbol(converter.mangleName(
-        std::get<const Fortran::semantics::Symbol &>(symClause)));
+  mlir::omp::TargetEnterExitUpdateDataClauseOps clauseOps;
+  genTargetEnterExitUpdateDataClauses(converter, semaCtx, stmtCtx, clauseList,
+                                      loc, directive, clauseOps);
 
-    if (!op) {
-      deferredDeclareTarget.push_back({std::get<0>(symClause),
-                                       clauseOps.deviceType,
-                                       std::get<1>(symClause)});
-    }
-  }
+  return firOpBuilder.create<OpTy>(loc, clauseOps);
 }
 
-static std::optional<mlir::omp::DeclareTargetDeviceType>
-getDeclareTargetFunctionDevice(
-    Fortran::lower::AbstractConverter &converter,
-    Fortran::semantics::SemanticsContext &semaCtx,
-    Fortran::lower::pft::Evaluation &eval,
-    const Fortran::parser::OpenMPDeclareTargetConstruct
-        &declareTargetConstruct) {
-  mlir::omp::DeclareTargetClauseOps clauseOps;
-  llvm::SmallVector<DeclareTargetCapturePair> symbolAndClause;
-  getDeclareTargetInfo(converter, semaCtx, eval, declareTargetConstruct,
-                       clauseOps, symbolAndClause);
-
-  // Return the device type only if at least one of the targets for the
-  // directive is a function or subroutine
-  mlir::ModuleOp mod = converter.getFirOpBuilder().getModule();
-  for (const DeclareTargetCapturePair &symClause : symbolAndClause) {
-    mlir::Operation *op = mod.lookupSymbol(converter.mangleName(
-        std::get<const Fortran::semantics::Symbol &>(symClause)));
-
-    if (mlir::isa_and_nonnull<mlir::func::FuncOp>(op))
-      return clauseOps.deviceType;
-  }
+static mlir::omp::TaskOp
+genTaskOp(Fortran::lower::AbstractConverter &converter,
+          Fortran::semantics::SemanticsContext &semaCtx,
+          Fortran::lower::pft::Evaluation &eval, bool genNested,
+          mlir::Location loc,
+          const Fortran::parser::OmpClauseList &clauseList) {
+  Fortran::lower::StatementContext stmtCtx;
+  mlir::omp::TaskClauseOps clauseOps;
+  genTaskClauses(converter, semaCtx, stmtCtx, clauseList, loc, clauseOps);
 
-  return std::nullopt;
+  return genOpWithBody<mlir::omp::TaskOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval)
+          .setGenNested(genNested)
+          .setClauses(&clauseList),
+      clauseOps);
 }
 
-//===----------------------------------------------------------------------===//
-// genOMP() Code generation helper functions
-//===----------------------------------------------------------------------===//
-
-static void
-genOmpSimpleStandalone(Fortran::lower::AbstractConverter &converter,
-                       Fortran::semantics::SemanticsContext &semaCtx,
-                       Fortran::lower::pft::Evaluation &eval, bool genNested,
-                       const Fortran::parser::OpenMPSimpleStandaloneConstruct
-                           &simpleStandaloneConstruct) {
-  const auto &directive =
-      std::get<Fortran::parser::OmpSimpleStandaloneDirective>(
-          simpleStandaloneConstruct.t);
-  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
-  const auto &opClauseList =
-      std::get<Fortran::parser::OmpClauseList>(simpleStandaloneConstruct.t);
-  mlir::Location currentLocation = converter.genLocation(directive.source);
-
-  switch (directive.v) {
-  default:
-    break;
-  case llvm::omp::Directive::OMPD_barrier:
-    firOpBuilder.create<mlir::omp::BarrierOp>(currentLocation);
-    break;
-  case llvm::omp::Directive::OMPD_taskwait: {
-    mlir::omp::TaskwaitClauseOps clauseOps;
-    ClauseProcessor cp(converter, semaCtx, opClauseList);
-    cp.processTODO<clause::Depend, clause::Nowait>(
-        currentLocation, llvm::omp::Directive::OMPD_taskwait);
-    firOpBuilder.create<mlir::omp::TaskwaitOp>(currentLocation, clauseOps);
-    break;
-  }
-  case llvm::omp::Directive::OMPD_taskyield:
-    firOpBuilder.create<mlir::omp::TaskyieldOp>(currentLocation);
-    break;
-  case llvm::omp::Directive::OMPD_target_data:
-    genTargetDataOp(converter, semaCtx, eval, genNested, currentLocation,
-                    opClauseList);
-    break;
-  case llvm::omp::Directive::OMPD_target_enter_data:
-    genTargetEnterExitDataUpdateOp<mlir::omp::TargetEnterDataOp>(
-        converter, semaCtx, currentLocation, opClauseList);
-    break;
-  case llvm::omp::Directive::OMPD_target_exit_data:
-    genTargetEnterExitDataUpdateOp<mlir::omp::TargetExitDataOp>(
-        converter, semaCtx, currentLocation, opClauseList);
-    break;
-  case llvm::omp::Directive::OMPD_target_update:
-    genTargetEnterExitDataUpdateOp<mlir::omp::TargetUpdateOp>(
-        converter, semaCtx, currentLocation, opClauseList);
-    break;
-  case llvm::omp::Directive::OMPD_ordered:
-    TODO(currentLocation, "OMPD_ordered");
-  }
-}
+static mlir::omp::TaskgroupOp
+genTaskgroupOp(Fortran::lower::AbstractConverter &converter,
+               Fortran::semantics::SemanticsContext &semaCtx,
+               Fortran::lower::pft::Evaluation &eval, bool genNested,
+               mlir::Location loc,
+               const Fortran::parser::OmpClauseList &clauseList) {
+  mlir::omp::TaskgroupClauseOps clauseOps;
+  genTaskgroupClauses(converter, semaCtx, clauseList, loc, clauseOps);
 
-static void
-genOmpFlush(Fortran::lower::AbstractConverter &converter,
-            Fortran::semantics::SemanticsContext &semaCtx,
-            Fortran::lower::pft::Evaluation &eval,
-            const Fortran::parser::OpenMPFlushConstruct &flushConstruct) {
-  llvm::SmallVector<mlir::Value, 4> operandRange;
-  if (const auto &ompObjectList =
-          std::get<std::optional<Fortran::parser::OmpObjectList>>(
-              flushConstruct.t))
-    genObjectList2(*ompObjectList, converter, operandRange);
-  const auto &memOrderClause =
-      std::get<std::optional<std::list<Fortran::parser::OmpMemoryOrderClause>>>(
-          flushConstruct.t);
-  if (memOrderClause && memOrderClause->size() > 0)
-    TODO(converter.getCurrentLocation(), "Handle OmpMemoryOrderClause");
-  converter.getFirOpBuilder().create<mlir::omp::FlushOp>(
-      converter.getCurrentLocation(), operandRange);
+  return genOpWithBody<mlir::omp::TaskgroupOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval)
+          .setGenNested(genNested)
+          .setClauses(&clauseList),
+      clauseOps);
 }
 
-static llvm::SmallVector<const Fortran::semantics::Symbol *>
-genLoopVars(mlir::Operation *op, Fortran::lower::AbstractConverter &converter,
-            mlir::Location &loc,
-            llvm::ArrayRef<const Fortran::semantics::Symbol *> args) {
-  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
-  auto &region = op->getRegion(0);
-
-  std::size_t loopVarTypeSize = 0;
-  for (const Fortran::semantics::Symbol *arg : args)
-    loopVarTypeSize = std::max(loopVarTypeSize, arg->GetUltimate().size());
-  mlir::Type loopVarType = getLoopVarType(converter, loopVarTypeSize);
-  llvm::SmallVector<mlir::Type> tiv(args.size(), loopVarType);
-  llvm::SmallVector<mlir::Location> locs(args.size(), loc);
-  firOpBuilder.createBlock(&region, {}, tiv, locs);
-  // The argument is not currently in memory, so make a temporary for the
-  // argument, and store it there, then bind that location to the argument.
-  mlir::Operation *storeOp = nullptr;
-  for (auto [argIndex, argSymbol] : llvm::enumerate(args)) {
-    mlir::Value indexVal = fir::getBase(region.front().getArgument(argIndex));
-    storeOp =
-        createAndSetPrivatizedLoopVar(converter, loc, indexVal, argSymbol);
-  }
-  firOpBuilder.setInsertionPointAfter(storeOp);
-
-  return llvm::SmallVector<const Fortran::semantics::Symbol *>(args);
+static mlir::omp::TaskloopOp
+genTaskloopOp(Fortran::lower::AbstractConverter &converter,
+              Fortran::semantics::SemanticsContext &semaCtx,
+              Fortran::lower::pft::Evaluation &eval, mlir::Location loc,
+              const Fortran::parser::OmpClauseList &clauseList) {
+  TODO(loc, "Taskloop construct");
 }
 
-static llvm::SmallVector<const Fortran::semantics::Symbol *>
-genLoopAndReductionVars(
-    mlir::Operation *op, Fortran::lower::AbstractConverter &converter,
-    mlir::Location &loc,
-    llvm::ArrayRef<const Fortran::semantics::Symbol *> loopArgs,
-    llvm::ArrayRef<const Fortran::semantics::Symbol *> reductionArgs,
-    llvm::ArrayRef<mlir::Type> reductionTypes) {
-  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
-
-  llvm::SmallVector<mlir::Type> blockArgTypes;
-  llvm::SmallVector<mlir::Location> blockArgLocs;
-  blockArgTypes.reserve(loopArgs.size() + reductionArgs.size());
-  blockArgLocs.reserve(blockArgTypes.size());
-  mlir::Block *entryBlock;
-
-  if (loopArgs.size()) {
-    std::size_t loopVarTypeSize = 0;
-    for (const Fortran::semantics::Symbol *arg : loopArgs)
-      loopVarTypeSize = std::max(loopVarTypeSize, arg->GetUltimate().size());
-    mlir::Type loopVarType = getLoopVarType(converter, loopVarTypeSize);
-    std::fill_n(std::back_inserter(blockArgTypes), loopArgs.size(),
-                loopVarType);
-    std::fill_n(std::back_inserter(blockArgLocs), loopArgs.size(), loc);
-  }
-  if (reductionArgs.size()) {
-    llvm::copy(reductionTypes, std::back_inserter(blockArgTypes));
-    std::fill_n(std::back_inserter(blockArgLocs), reductionArgs.size(), loc);
-  }
-  entryBlock = firOpBuilder.createBlock(&op->getRegion(0), {}, blockArgTypes,
-                                        blockArgLocs);
-  // The argument is not currently in memory, so make a temporary for the
-  // argument, and store it there, then bind that location to the argument.
-  if (loopArgs.size()) {
-    mlir::Operation *storeOp = nullptr;
-    for (auto [argIndex, argSymbol] : llvm::enumerate(loopArgs)) {
-      mlir::Value indexVal =
-          fir::getBase(op->getRegion(0).front().getArgument(argIndex));
-      storeOp =
-          createAndSetPrivatizedLoopVar(converter, loc, indexVal, argSymbol);
-    }
-    firOpBuilder.setInsertionPointAfter(storeOp);
-  }
-  // Bind the reduction arguments to their block arguments
-  for (auto [arg, prv] : llvm::zip_equal(
-           reductionArgs,
-           llvm::drop_begin(entryBlock->getArguments(), loopArgs.size()))) {
-    converter.bindSymbol(*arg, prv);
-  }
-
-  return llvm::SmallVector<const Fortran::semantics::Symbol *>(loopArgs);
+static mlir::omp::TaskwaitOp
+genTaskwaitOp(Fortran::lower::AbstractConverter &converter,
+              Fortran::semantics::SemanticsContext &semaCtx,
+              Fortran::lower::pft::Evaluation &eval, mlir::Location loc,
+              const Fortran::parser::OmpClauseList &clauseList) {
+  mlir::omp::TaskwaitClauseOps clauseOps;
+  genTaskwaitClauses(converter, semaCtx, clauseList, loc, clauseOps);
+  return converter.getFirOpBuilder().create<mlir::omp::TaskwaitOp>(loc,
+                                                                   clauseOps);
 }
 
-static void
-createSimdLoop(Fortran::lower::AbstractConverter &converter,
+static mlir::omp::TaskyieldOp
+genTaskyieldOp(Fortran::lower::AbstractConverter &converter,
                Fortran::semantics::SemanticsContext &semaCtx,
-               Fortran::lower::pft::Evaluation &eval,
-               llvm::omp::Directive ompDirective,
-               const Fortran::parser::OmpClauseList &loopOpClauseList,
-               mlir::Location loc) {
-  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
-  DataSharingProcessor dsp(converter, semaCtx, loopOpClauseList, eval);
-  dsp.processStep1();
+               Fortran::lower::pft::Evaluation &eval, mlir::Location loc) {
+  return converter.getFirOpBuilder().create<mlir::omp::TaskyieldOp>(loc);
+}
 
+static mlir::omp::TeamsOp
+genTeamsOp(Fortran::lower::AbstractConverter &converter,
+           Fortran::semantics::SemanticsContext &semaCtx,
+           Fortran::lower::pft::Evaluation &eval, bool genNested,
+           mlir::Location loc, const Fortran::parser::OmpClauseList &clauseList,
+           bool outerCombined = false) {
   Fortran::lower::StatementContext stmtCtx;
-  mlir::omp::SimdLoopClauseOps clauseOps;
-  llvm::SmallVector<const Fortran::semantics::Symbol *> iv;
-
-  ClauseProcessor cp(converter, semaCtx, loopOpClauseList);
-  cp.processCollapse(loc, eval, clauseOps, iv);
-  cp.processReduction(loc, clauseOps);
-  cp.processIf(llvm::omp::Directive::OMPD_simd, clauseOps);
-  cp.processSimdlen(clauseOps);
-  cp.processSafelen(clauseOps);
-  clauseOps.loopInclusiveAttr = firOpBuilder.getUnitAttr();
-  // TODO Support delayed privatization.
-
-  cp.processTODO<clause::Aligned, clause::Allocate, clause::Linear,
-                 clause::Nontemporal, clause::Order>(loc, ompDirective);
-
-  auto *nestedEval = getCollapsedLoopEval(
-      eval, Fortran::lower::getCollapseValue(loopOpClauseList));
-
-  auto ivCallback = [&](mlir::Operation *op) {
-    return genLoopVars(op, converter, loc, iv);
-  };
+  mlir::omp::TeamsClauseOps clauseOps;
+  genTeamsClauses(converter, semaCtx, stmtCtx, clauseList, loc, clauseOps);
 
-  genOpWithBody<mlir::omp::SimdLoopOp>(
-      OpWithBodyGenInfo(converter, semaCtx, loc, *nestedEval)
-          .setClauses(&loopOpClauseList)
-          .setDataSharingProcessor(&dsp)
-          .setGenRegionEntryCb(ivCallback),
+  return genOpWithBody<mlir::omp::TeamsOp>(
+      OpWithBodyGenInfo(converter, semaCtx, loc, eval)
+          .setGenNested(genNested)
+          .setOuterCombined(outerCombined)
+          .setClauses(&clauseList),
       clauseOps);
 }
 
-static void createWsloop(Fortran::lower::AbstractConverter &converter,
-                         Fortran::semantics::SemanticsContext &semaCtx,
-                         Fortran::lower::pft::Evaluation &eval,
-                         llvm::omp::Directive ompDirective,
-                         const Fortran::parser::OmpClauseList &beginClauseList,
-                         const Fortran::parser::OmpClauseList *endClauseList,
-                         mlir::Location loc) {
-  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+static mlir::omp::WsloopOp
+genWsloopOp(Fortran::lower::AbstractConverter &converter,
+            Fortran::semantics::SemanticsContext &semaCtx,
+            Fortran::lower::pft::Evaluation &eval, mlir::Location loc,
+            const Fortran::parser::OmpClauseList &beginClauseList,
+            const Fortran::parser::OmpClauseList *endClauseList) {
   DataSharingProcessor dsp(converter, semaCtx, beginClauseList, eval);
   dsp.processStep1();
 
@@ -1461,30 +1725,9 @@ static void createWsloop(Fortran::lower::AbstractConverter &converter,
   llvm::SmallVector<const Fortran::semantics::Symbol *> iv;
   llvm::SmallVector<mlir::Type> reductionTypes;
   llvm::SmallVector<const Fortran::semantics::Symbol *> reductionSyms;
-
-  ClauseProcessor cp(converter, semaCtx, beginClauseList);
-  cp.processCollapse(loc, eval, clauseOps, iv);
-  cp.processSchedule(stmtCtx, clauseOps);
-  cp.processReduction(loc, clauseOps, &reductionTypes, &reductionSyms);
-  cp.processOrdered(clauseOps);
-  clauseOps.loopInclusiveAttr = firOpBuilder.getUnitAttr();
-  // TODO Support delayed privatization.
-
-  if (ReductionProcessor::doReductionByRef(clauseOps.reductionVars))
-    clauseOps.reductionByRefAttr = firOpBuilder.getUnitAttr();
-
-  cp.processTODO<clause::Allocate, clause::Linear, clause::Order>(loc,
-                                                                  ompDirective);
-
-  // In FORTRAN `nowait` clause occur at the end of `omp do` directive.
-  // i.e
-  // !$omp do
-  // <...>
-  // !$omp end do nowait
-  if (endClauseList) {
-    ClauseProcessor ecp(converter, semaCtx, *endClauseList);
-    ecp.processNowait(clauseOps);
-  }
+  genWsloopClauses(converter, semaCtx, stmtCtx, eval, beginClauseList,
+                   endClauseList, loc, clauseOps, iv, reductionTypes,
+                   reductionSyms);
 
   auto *nestedEval = getCollapsedLoopEval(
       eval, Fortran::lower::getCollapseValue(beginClauseList));
@@ -1494,7 +1737,7 @@ static void createWsloop(Fortran::lower::AbstractConverter &converter,
                                    reductionTypes);
   };
 
-  genOpWithBody<mlir::omp::WsloopOp>(
+  return genOpWithBody<mlir::omp::WsloopOp>(
       OpWithBodyGenInfo(converter, semaCtx, loc, *nestedEval)
           .setClauses(&beginClauseList)
           .setDataSharingProcessor(&dsp)
@@ -1503,7 +1746,11 @@ static void createWsloop(Fortran::lower::AbstractConverter &converter,
       clauseOps);
 }
 
-static void createSimdWsloop(
+//===----------------------------------------------------------------------===//
+// Code generation functions for composite constructs
+//===----------------------------------------------------------------------===//
+
+static void genCompositeDoSimd(
     Fortran::lower::AbstractConverter &converter,
     Fortran::semantics::SemanticsContext &semaCtx,
     Fortran::lower::pft::Evaluation &eval, llvm::omp::Directive ompDirective,
@@ -1511,7 +1758,7 @@ static void createSimdWsloop(
     const Fortran::parser::OmpClauseList *endClauseList, mlir::Location loc) {
   ClauseProcessor cp(converter, semaCtx, beginClauseList);
   cp.processTODO<clause::Aligned, clause::Allocate, clause::Linear,
-                 clause::Safelen, clause::Simdlen, clause::Order>(loc,
+                 clause::Order, clause::Safelen, clause::Simdlen>(loc,
                                                                   ompDirective);
   // TODO: Add support for vectorization - add vectorization hints inside loop
   // body.
@@ -1521,34 +1768,7 @@ static void createSimdWsloop(
   // When support for vectorization is enabled, then we need to add handling of
   // if clause. Currently if clause can be skipped because we always assume
   // SIMD length = 1.
-  createWsloop(converter, semaCtx, eval, ompDirective, beginClauseList,
-               endClauseList, loc);
-}
-
-static void
-markDeclareTarget(mlir::Operation *op,
-                  Fortran::lower::AbstractConverter &converter,
-                  mlir::omp::DeclareTargetCaptureClause captureClause,
-                  mlir::omp::DeclareTargetDeviceType deviceType) {
-  // TODO: Add support for program local variables with declare target applied
-  auto declareTargetOp = llvm::dyn_cast<mlir::omp::DeclareTargetInterface>(op);
-  if (!declareTargetOp)
-    fir::emitFatalError(
-        converter.getCurrentLocation(),
-        "Attempt to apply declare target on unsupported operation");
-
-  // The function or global already has a declare target applied to it, very
-  // likely through implicit capture (usage in another declare target
-  // function/subroutine). It should be marked as any if it has been assigned
-  // both host and nohost, else we skip, as there is no change
-  if (declareTargetOp.isDeclareTarget()) {
-    if (declareTargetOp.getDeclareTargetDeviceType() != deviceType)
-      declareTargetOp.setDeclareTarget(mlir::omp::DeclareTargetDeviceType::any,
-                                       captureClause);
-    return;
-  }
-
-  declareTargetOp.setDeclareTarget(deviceType, captureClause);
+  genWsloopOp(converter, semaCtx, eval, loc, beginClauseList, endClauseList);
 }
 
 //===----------------------------------------------------------------------===//
@@ -1644,6 +1864,102 @@ genOMP(Fortran::lower::AbstractConverter &converter,
 }
 
 //===----------------------------------------------------------------------===//
+// OpenMPStandaloneConstruct visitors
+//===----------------------------------------------------------------------===//
+
+static void genOMP(Fortran::lower::AbstractConverter &converter,
+                   Fortran::lower::SymMap &symTable,
+                   Fortran::semantics::SemanticsContext &semaCtx,
+                   Fortran::lower::pft::Evaluation &eval,
+                   const Fortran::parser::OpenMPSimpleStandaloneConstruct
+                       &simpleStandaloneConstruct) {
+  const auto &directive =
+      std::get<Fortran::parser::OmpSimpleStandaloneDirective>(
+          simpleStandaloneConstruct.t);
+  const auto &clauseList =
+      std::get<Fortran::parser::OmpClauseList>(simpleStandaloneConstruct.t);
+  mlir::Location currentLocation = converter.genLocation(directive.source);
+
+  switch (directive.v) {
+  default:
+    break;
+  case llvm::omp::Directive::OMPD_barrier:
+    genBarrierOp(converter, semaCtx, eval, currentLocation);
+    break;
+  case llvm::omp::Directive::OMPD_taskwait:
+    genTaskwaitOp(converter, semaCtx, eval, currentLocation, clauseList);
+    break;
+  case llvm::omp::Directive::OMPD_taskyield:
+    genTaskyieldOp(converter, semaCtx, eval, currentLocation);
+    break;
+  case llvm::omp::Directive::OMPD_target_data:
+    genTargetDataOp(converter, semaCtx, eval, /*genNested=*/true,
+                    currentLocation, clauseList);
+    break;
+  case llvm::omp::Directive::OMPD_target_enter_data:
+    genTargetEnterExitUpdateDataOp<mlir::omp::TargetEnterDataOp>(
+        converter, semaCtx, currentLocation, clauseList);
+    break;
+  case llvm::omp::Directive::OMPD_target_exit_data:
+    genTargetEnterExitUpdateDataOp<mlir::omp::TargetExitDataOp>(
+        converter, semaCtx, currentLocation, clauseList);
+    break;
+  case llvm::omp::Directive::OMPD_target_update:
+    genTargetEnterExitUpdateDataOp<mlir::omp::TargetUpdateOp>(
+        converter, semaCtx, currentLocation, clauseList);
+    break;
+  case llvm::omp::Directive::OMPD_ordered:
+    genOrderedOp(converter, semaCtx, eval, currentLocation, clauseList);
+    break;
+  }
+}
+
+static void
+genOMP(Fortran::lower::AbstractConverter &converter,
+       Fortran::lower::SymMap &symTable,
+       Fortran::semantics::SemanticsContext &semaCtx,
+       Fortran::lower::pft::Evaluation &eval,
+       const Fortran::parser::OpenMPFlushConstruct &flushConstruct) {
+  const auto &verbatim = std::get<Fortran::parser::Verbatim>(flushConstruct.t);
+  const auto &objectList =
+      std::get<std::optional<Fortran::parser::OmpObjectList>>(flushConstruct.t);
+  const auto &clauseList =
+      std::get<std::optional<std::list<Fortran::parser::OmpMemoryOrderClause>>>(
+          flushConstruct.t);
+  mlir::Location currentLocation = converter.genLocation(verbatim.source);
+  genFlushOp(converter, semaCtx, eval, currentLocation, objectList, clauseList);
+}
+
+static void
+genOMP(Fortran::lower::AbstractConverter &converter,
+       Fortran::lower::SymMap &symTable,
+       Fortran::semantics::SemanticsContext &semaCtx,
+       Fortran::lower::pft::Evaluation &eval,
+       const Fortran::parser::OpenMPCancelConstruct &cancelConstruct) {
+  TODO(converter.getCurrentLocation(), "OpenMPCancelConstruct");
+}
+
+static void genOMP(Fortran::lower::AbstractConverter &converter,
+                   Fortran::lower::SymMap &symTable,
+                   Fortran::semantics::SemanticsContext &semaCtx,
+                   Fortran::lower::pft::Evaluation &eval,
+                   const Fortran::parser::OpenMPCancellationPointConstruct
+                       &cancellationPointConstruct) {
+  TODO(converter.getCurrentLocation(), "OpenMPCancelConstruct");
+}
+
+static void
+genOMP(Fortran::lower::AbstractConverter &converter,
+       Fortran::lower::SymMap &symTable,
+       Fortran::semantics::SemanticsContext &semaCtx,
+       Fortran::lower::pft::Evaluation &eval,
+       const Fortran::parser::OpenMPStandaloneConstruct &standaloneConstruct) {
+  std::visit(
+      [&](auto &&s) { return genOMP(converter, symTable, semaCtx, eval, s); },
+      standaloneConstruct.u);
+}
+
+//===----------------------------------------------------------------------===//
 // OpenMPConstruct visitors
 //===----------------------------------------------------------------------===//
 
@@ -1774,7 +2090,7 @@ genOMP(Fortran::lower::AbstractConverter &converter,
     break;
   case llvm::omp::Directive::OMPD_target:
     genTargetOp(converter, semaCtx, eval, /*genNested=*/true, currentLocation,
-                beginClauseList, directive.v);
+                beginClauseList);
     break;
   case llvm::omp::Directive::OMPD_target_data:
     genTargetDataOp(converter, semaCtx, eval, /*genNested=*/true,
@@ -1790,8 +2106,7 @@ genOMP(Fortran::lower::AbstractConverter &converter,
     break;
   case llvm::omp::Directive::OMPD_teams:
     genTeamsOp(converter, semaCtx, eval, /*genNested=*/true, currentLocation,
-               beginClauseList,
-               /*outerCombined=*/false);
+               beginClauseList);
     break;
   case llvm::omp::Directive::OMPD_workshare:
     // FIXME: Workshare is not a commonly used OpenMP construct, an
@@ -1813,8 +2128,7 @@ genOMP(Fortran::lower::AbstractConverter &converter,
   if ((llvm::omp::allTargetSet & llvm::omp::blockConstructSet)
           .test(directive.v)) {
     genTargetOp(converter, semaCtx, eval, /*genNested=*/false, currentLocation,
-                beginClauseList, directive.v,
-                /*outerCombined=*/true);
+                beginClauseList, /*outerCombined=*/true);
     combinedDirective = true;
   }
   if ((llvm::omp::allTeamsSet & llvm::omp::blockConstructSet)
@@ -1851,44 +2165,13 @@ genOMP(Fortran::lower::AbstractConverter &converter,
        Fortran::semantics::SemanticsContext &semaCtx,
        Fortran::lower::pft::Evaluation &eval,
        const Fortran::parser::OpenMPCriticalConstruct &criticalConstruct) {
-  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
-  mlir::Location currentLocation = converter.getCurrentLocation();
-  std::string name;
-  const Fortran::parser::OmpCriticalDirective &cd =
+  const auto &cd =
       std::get<Fortran::parser::OmpCriticalDirective>(criticalConstruct.t);
-  if (std::get<std::optional<Fortran::parser::Name>>(cd.t).has_value()) {
-    name =
-        std::get<std::optional<Fortran::parser::Name>>(cd.t).value().ToString();
-  }
-
-  mlir::omp::CriticalOp criticalOp = [&]() {
-    if (name.empty()) {
-      return firOpBuilder.create<mlir::omp::CriticalOp>(
-          currentLocation, mlir::FlatSymbolRefAttr());
-    }
-
-    mlir::ModuleOp module = firOpBuilder.getModule();
-    mlir::OpBuilder modBuilder(module.getBodyRegion());
-    auto global = module.lookupSymbol<mlir::omp::CriticalDeclareOp>(name);
-    if (!global) {
-      mlir::omp::CriticalClauseOps clauseOps;
-      const auto &clauseList = std::get<Fortran::parser::OmpClauseList>(cd.t);
-
-      ClauseProcessor cp(converter, semaCtx, clauseList);
-      cp.processHint(clauseOps);
-      clauseOps.nameAttr =
-          mlir::StringAttr::get(firOpBuilder.getContext(), name);
-
-      global = modBuilder.create<mlir::omp::CriticalDeclareOp>(currentLocation,
-                                                               clauseOps);
-    }
-
-    return firOpBuilder.create<mlir::omp::CriticalOp>(
-        currentLocation, mlir::FlatSymbolRefAttr::get(firOpBuilder.getContext(),
-                                                      global.getSymName()));
-  }();
-  auto genInfo = OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval);
-  createBodyOfOp<mlir::omp::CriticalOp>(criticalOp, genInfo);
+  const auto &clauseList = std::get<Fortran::parser::OmpClauseList>(cd.t);
+  const auto &name = std::get<std::optional<Fortran::parser::Name>>(cd.t);
+  mlir::Location currentLocation = converter.getCurrentLocation();
+  genCriticalOp(converter, semaCtx, eval, /*genNested=*/true, currentLocation,
+                clauseList, name);
 }
 
 static void
@@ -1907,7 +2190,7 @@ static void genOMP(Fortran::lower::AbstractConverter &converter,
                    const Fortran::parser::OpenMPLoopConstruct &loopConstruct) {
   const auto &beginLoopDirective =
       std::get<Fortran::parser::OmpBeginLoopDirective>(loopConstruct.t);
-  const auto &loopOpClauseList =
+  const auto &beginClauseList =
       std::get<Fortran::parser::OmpClauseList>(beginLoopDirective.t);
   mlir::Location currentLocation =
       converter.genLocation(beginLoopDirective.source);
@@ -1928,33 +2211,31 @@ static void genOMP(Fortran::lower::AbstractConverter &converter,
   bool validDirective = false;
   if (llvm::omp::topTaskloopSet.test(ompDirective)) {
     validDirective = true;
-    TODO(currentLocation, "Taskloop construct");
+    genTaskloopOp(converter, semaCtx, eval, currentLocation, beginClauseList);
   } else {
     // Create omp.{target, teams, distribute, parallel} nested operations
     if ((llvm::omp::allTargetSet & llvm::omp::loopConstructSet)
             .test(ompDirective)) {
       validDirective = true;
       genTargetOp(converter, semaCtx, eval, /*genNested=*/false,
-                  currentLocation, loopOpClauseList, ompDirective,
-                  /*outerCombined=*/true);
+                  currentLocation, beginClauseList, /*outerCombined=*/true);
     }
     if ((llvm::omp::allTeamsSet & llvm::omp::loopConstructSet)
             .test(ompDirective)) {
       validDirective = true;
       genTeamsOp(converter, semaCtx, eval, /*genNested=*/false, currentLocation,
-                 loopOpClauseList,
-                 /*outerCombined=*/true);
+                 beginClauseList, /*outerCombined=*/true);
     }
     if (llvm::omp::allDistributeSet.test(ompDirective)) {
       validDirective = true;
-      TODO(currentLocation, "Distribute construct");
+      genDistributeOp(converter, semaCtx, eval, /*genNested=*/false,
+                      currentLocation, beginClauseList);
     }
     if ((llvm::omp::allParallelSet & llvm::omp::loopConstructSet)
             .test(ompDirective)) {
       validDirective = true;
       genParallelOp(converter, symTable, semaCtx, eval, /*genNested=*/false,
-                    currentLocation, loopOpClauseList,
-                    /*outerCombined=*/true);
+                    currentLocation, beginClauseList, /*outerCombined=*/true);
     }
   }
   if ((llvm::omp::allDoSet | llvm::omp::allSimdSet).test(ompDirective))
@@ -1968,16 +2249,14 @@ static void genOMP(Fortran::lower::AbstractConverter &converter,
 
   if (llvm::omp::allDoSimdSet.test(ompDirective)) {
     // 2.9.3.2 Workshare SIMD construct
-    createSimdWsloop(converter, semaCtx, eval, ompDirective, loopOpClauseList,
-                     endClauseList, currentLocation);
-
+    genCompositeDoSimd(converter, semaCtx, eval, ompDirective, beginClauseList,
+                       endClauseList, currentLocation);
   } else if (llvm::omp::allSimdSet.test(ompDirective)) {
     // 2.9.3.1 SIMD construct
-    createSimdLoop(converter, semaCtx, eval, ompDirective, loopOpClauseList,
-                   currentLocation);
+    genSimdLoopOp(converter, semaCtx, eval, currentLocation, beginClauseList);
   } else {
-    createWsloop(converter, semaCtx, eval, ompDirective, loopOpClauseList,
-                 endClauseList, currentLocation);
+    genWsloopOp(converter, semaCtx, eval, currentLocation, beginClauseList,
+                endClauseList);
   }
 }
 
@@ -1997,44 +2276,39 @@ genOMP(Fortran::lower::AbstractConverter &converter,
        Fortran::semantics::SemanticsContext &semaCtx,
        Fortran::lower::pft::Evaluation &eval,
        const Fortran::parser::OpenMPSectionsConstruct &sectionsConstruct) {
-  mlir::Location currentLocation = converter.getCurrentLocation();
-  mlir::omp::SectionsClauseOps clauseOps;
   const auto &beginSectionsDirective =
       std::get<Fortran::parser::OmpBeginSectionsDirective>(sectionsConstruct.t);
-  const auto &sectionsClauseList =
+  const auto &beginClauseList =
       std::get<Fortran::parser::OmpClauseList>(beginSectionsDirective.t);
 
   // Process clauses before optional omp.parallel, so that new variables are
   // allocated outside of the parallel region
-  ClauseProcessor cp(converter, semaCtx, sectionsClauseList);
-  cp.processSectionsReduction(currentLocation, clauseOps);
-  cp.processAllocate(clauseOps);
-  // TODO Support delayed privatization.
+  mlir::Location currentLocation = converter.getCurrentLocation();
+  mlir::omp::SectionsClauseOps clauseOps;
+  genSectionsClauses(converter, semaCtx, beginClauseList, currentLocation,
+                     /*clausesFromBeginSections=*/true, clauseOps);
 
+  // Parallel wrapper of PARALLEL SECTIONS construct
   llvm::omp::Directive dir =
       std::get<Fortran::parser::OmpSectionsDirective>(beginSectionsDirective.t)
           .v;
-
-  // Parallel wrapper of PARALLEL SECTIONS construct
   if (dir == llvm::omp::Directive::OMPD_parallel_sections) {
     genParallelOp(converter, symTable, semaCtx, eval,
-                  /*genNested=*/false, currentLocation, sectionsClauseList,
+                  /*genNested=*/false, currentLocation, beginClauseList,
                   /*outerCombined=*/true);
   } else {
     const auto &endSectionsDirective =
         std::get<Fortran::parser::OmpEndSectionsDirective>(sectionsConstruct.t);
-    const auto &endSectionsClauseList =
+    const auto &endClauseList =
         std::get<Fortran::parser::OmpClauseList>(endSectionsDirective.t);
-    ClauseProcessor(converter, semaCtx, endSectionsClauseList)
-        .processNowait(clauseOps);
+    genSectionsClauses(converter, semaCtx, endClauseList, currentLocation,
+                       /*clausesFromBeginSections=*/false, clauseOps);
   }
 
-  // SECTIONS construct
-  genOpWithBody<mlir::omp::SectionsOp>(
-      OpWithBodyGenInfo(converter, semaCtx, currentLocation, eval)
-          .setGenNested(false),
-      clauseOps);
+  // SECTIONS construct.
+  genSectionsOp(converter, semaCtx, eval, currentLocation, clauseOps);
 
+  // Generate nested SECTION operations recursively.
   const auto &sectionBlocks =
       std::get<Fortran::parser::OmpSectionBlocks>(sectionsConstruct.t);
   auto &firOpBuilder = converter.getFirOpBuilder();
@@ -2043,40 +2317,12 @@ genOMP(Fortran::lower::AbstractConverter &converter,
        llvm::zip(sectionBlocks.v, eval.getNestedEvaluations())) {
     symTable.pushScope();
     genSectionOp(converter, semaCtx, neval, /*genNested=*/true, currentLocation,
-                 sectionsClauseList);
+                 beginClauseList);
     symTable.popScope();
     firOpBuilder.restoreInsertionPoint(ip);
   }
 }
 
-static void
-genOMP(Fortran::lower::AbstractConverter &converter,
-       Fortran::lower::SymMap &symTable,
-       Fortran::semantics::SemanticsContext &semaCtx,
-       Fortran::lower::pft::Evaluation &eval,
-       const Fortran::parser::OpenMPStandaloneConstruct &standaloneConstruct) {
-  std::visit(
-      Fortran::common::visitors{
-          [&](const Fortran::parser::OpenMPSimpleStandaloneConstruct
-                  &simpleStandaloneConstruct) {
-            genOmpSimpleStandalone(converter, semaCtx, eval,
-                                   /*genNested=*/true,
-                                   simpleStandaloneConstruct);
-          },
-          [&](const Fortran::parser::OpenMPFlushConstruct &flushConstruct) {
-            genOmpFlush(converter, semaCtx, eval, flushConstruct);
-          },
-          [&](const Fortran::parser::OpenMPCancelConstruct &cancelConstruct) {
-            TODO(converter.getCurrentLocation(), "OpenMPCancelConstruct");
-          },
-          [&](const Fortran::parser::OpenMPCancellationPointConstruct
-                  &cancellationPointConstruct) {
-            TODO(converter.getCurrentLocation(), "OpenMPCancelConstruct");
-          },
-      },
-      standaloneConstruct.u);
-}
-
 static void genOMP(Fortran::lower::AbstractConverter &converter,
                    Fortran::lower::SymMap &symTable,
                    Fortran::semantics::SemanticsContext &semaCtx,
diff --git a/flang/test/Lower/OpenMP/FIR/target.f90 b/flang/test/Lower/OpenMP/FIR/target.f90
index 022327f9c25d..ca3162340d78 100644
--- a/flang/test/Lower/OpenMP/FIR/target.f90
+++ b/flang/test/Lower/OpenMP/FIR/target.f90
@@ -411,8 +411,8 @@ end subroutine omp_target_implicit_bounds
 !CHECK-LABEL: func.func @_QPomp_target_thread_limit() {
 subroutine omp_target_thread_limit
    integer :: a
-   !CHECK: %[[VAL_1:.*]] = arith.constant 64 : i32
    !CHECK: %[[MAP:.*]] = omp.map.info var_ptr({{.*}})   map_clauses(tofrom) capture(ByRef) -> !fir.ref<i32> {name = "a"}
+   !CHECK: %[[VAL_1:.*]] = arith.constant 64 : i32
    !CHECK: omp.target   thread_limit(%[[VAL_1]] : i32) map_entries(%[[MAP]] -> %[[ARG_0:.*]] : !fir.ref<i32>) {
    !CHECK: ^bb0(%[[ARG_0]]: !fir.ref<i32>):
    !$omp target map(tofrom: a) thread_limit(64)
diff --git a/flang/test/Lower/OpenMP/target.f90 b/flang/test/Lower/OpenMP/target.f90
index 6f72b5a34d06..51b66327dfb2 100644
--- a/flang/test/Lower/OpenMP/target.f90
+++ b/flang/test/Lower/OpenMP/target.f90
@@ -490,8 +490,8 @@ end subroutine omp_target_implicit_bounds
 !CHECK-LABEL: func.func @_QPomp_target_thread_limit() {
 subroutine omp_target_thread_limit
    integer :: a
-   !CHECK: %[[VAL_1:.*]] = arith.constant 64 : i32
    !CHECK: %[[MAP:.*]] = omp.map.info var_ptr({{.*}})   map_clauses(tofrom) capture(ByRef) -> !fir.ref<i32> {name = "a"}
+   !CHECK: %[[VAL_1:.*]] = arith.constant 64 : i32
    !CHECK: omp.target   thread_limit(%[[VAL_1]] : i32) map_entries(%[[MAP]] -> %{{.*}} : !fir.ref<i32>) {
    !CHECK: ^bb0(%{{.*}}: !fir.ref<i32>):
    !$omp target map(tofrom: a) thread_limit(64)
diff --git a/flang/test/Lower/OpenMP/use-device-ptr-to-use-device-addr.f90 b/flang/test/Lower/OpenMP/use-device-ptr-to-use-device-addr.f90
index 33b597165601..d849dd206b94 100644
--- a/flang/test/Lower/OpenMP/use-device-ptr-to-use-device-addr.f90
+++ b/flang/test/Lower/OpenMP/use-device-ptr-to-use-device-addr.f90
@@ -21,7 +21,7 @@ end subroutine
 
 !CHECK: func.func @{{.*}}mix_use_device_ptr_and_addr()
 !CHECK: omp.target_data use_device_ptr({{.*}} : !fir.ref<!fir.type<_QM__fortran_builtinsT__builtin_c_ptr{__address:i64}>>) use_device_addr(%{{.*}}, %{{.*}} : !fir.ref<!fir.box<!fir.ptr<!fir.array<?xi32>>>>, !fir.ref<!fir.box<!fir.ptr<!fir.array<?xf32>>>>) {
-!CHECK: ^bb0(%{{.*}}: !fir.ref<!fir.type<_QM__fortran_builtinsT__builtin_c_ptr{__address:i64}>>, %{{.*}}: !fir.ref<!fir.box<!fir.ptr<!fir.array<?xi32>>>>, %{{.*}}: !fir.ref<!fir.box<!fir.ptr<!fir.array<?xf32>>>>):
+!CHECK: ^bb0(%{{.*}}: !fir.ref<!fir.box<!fir.ptr<!fir.array<?xf32>>>>, %{{.*}}: !fir.ref<!fir.type<_QM__fortran_builtinsT__builtin_c_ptr{__address:i64}>>, %{{.*}}: !fir.ref<!fir.box<!fir.ptr<!fir.array<?xi32>>>>):
 subroutine mix_use_device_ptr_and_addr 
     use iso_c_binding
     integer, pointer, dimension(:) :: array
@@ -47,7 +47,7 @@ end subroutine
 
 !CHECK: func.func @{{.*}}mix_use_device_ptr_and_addr_and_map()
 !CHECK: omp.target_data map_entries(%{{.*}}, %{{.*}} : !fir.ref<i32>, !fir.ref<i32>) use_device_ptr(%{{.*}} : !fir.ref<!fir.type<_QM__fortran_builtinsT__builtin_c_ptr{__address:i64}>>) use_device_addr(%{{.*}}, %{{.*}} : !fir.ref<!fir.box<!fir.ptr<!fir.array<?xi32>>>>, !fir.ref<!fir.box<!fir.ptr<!fir.array<?xf32>>>>) {
-!CHECK: ^bb0(%{{.*}}: !fir.ref<!fir.type<_QM__fortran_builtinsT__builtin_c_ptr{__address:i64}>>, %{{.*}}: !fir.ref<!fir.box<!fir.ptr<!fir.array<?xi32>>>>, %{{.*}}: !fir.ref<!fir.box<!fir.ptr<!fir.array<?xf32>>>>):
+!CHECK: ^bb0(%{{.*}}: !fir.ref<!fir.box<!fir.ptr<!fir.array<?xf32>>>>, %{{.*}}: !fir.ref<!fir.type<_QM__fortran_builtinsT__builtin_c_ptr{__address:i64}>>, %{{.*}}: !fir.ref<!fir.box<!fir.ptr<!fir.array<?xi32>>>>):
 subroutine mix_use_device_ptr_and_addr_and_map
     use iso_c_binding
     integer :: i, j