[flang][openacc] Lower the entry part for OpenACC declare in function/subroutine

[clementval]

Summary

This patch adds lowering for the entry part of the OpenACC declare construct
in function/subroutine. The exit part will come as a follow up patch.

[razvanlupusoru]

Looks great!

flang/lib/Lower/OpenACC.cpp

static Op createDataEntryOp(fir::FirOpBuilder &builder, mlir::Location loc,
   if (bounds.size() > 0)
     op->insertOperands(insPos, bounds);
   op->setAttr(Op::getOperandSegmentSizeAttr(),
               builder.getDenseI32ArrayAttr(
                   {1, varPtrPtr ? 1 : 0, static_cast<int32_t>(bounds.size())}));
   return op;
 }
 
+static void addDeclareAttr(fir::FirOpBuilder &builder, mlir::Operation *op,
+                           mlir::acc::DataClause clause) {
+  op->setAttr(mlir::acc::getDeclareAttrName(),
+              mlir::acc::DeclareAttr::get(builder.getContext(),
+                                          mlir::acc::DataClauseAttr::get(
+                                              builder.getContext(), clause)));
+}
+
 template <typename Op>
 static void
 genDataOperandOperations(const Fortran::parser::AccObjectList &objectList,
                          Fortran::lower::AbstractConverter &converter,
                          Fortran::semantics::SemanticsContext &semanticsContext,
                          Fortran::lower::StatementContext &stmtCtx,
                          llvm::SmallVectorImpl<mlir::Value> &dataOperands,
-                         mlir::acc::DataClause dataClause, bool structured) {
+                         mlir::acc::DataClause dataClause, bool structured,
+                         bool setDeclareAttr = false) {
   fir::FirOpBuilder &builder = converter.getFirOpBuilder();
   for (const auto &accObject : objectList.v) {
     llvm::SmallVector<mlir::Value> bounds;
     std::stringstream asFortran;
     mlir::Location operandLocation = genOperandLocation(converter, accObject);
     mlir::Value baseAddr = gatherDataOperandAddrAndBounds(
         converter, builder, semanticsContext, stmtCtx, accObject,
         operandLocation, asFortran, bounds);
     Op op = createDataEntryOp<Op>(builder, operandLocation, baseAddr, asFortran,
                                   bounds, structured, dataClause,
                                   baseAddr.getType());
     dataOperands.push_back(op.getAccPtr());
+    if (setDeclareAttr)
+      addDeclareAttr(builder, op.getVarPtr().getDefiningOp(), dataClause);
   }
 }
 
 template <typename EntryOp, typename ExitOp>
 static void genDataExitOperations(fir::FirOpBuilder &builder,
                                   llvm::SmallVector<mlir::Value> operands,
                                   bool structured, bool implicit) {
   for (mlir::Value operand : operands) {
static void genACC(Fortran::lower::AbstractConverter &converter,
 
   mlir::acc::WaitOp waitOp = createSimpleOp<mlir::acc::WaitOp>(
       firOpBuilder, currentLocation, operands, operandSegments);
 
   if (addAsyncAttr)
     waitOp.setAsyncAttr(firOpBuilder.getUnitAttr());
 }
 
-static void addDeclareAttr(fir::FirOpBuilder &builder, mlir::Operation *op,
-                           mlir::acc::DataClause clause) {
-  op->setAttr(mlir::acc::getDeclareAttrName(),
-              mlir::acc::DeclareAttr::get(builder.getContext(),
-                                          mlir::acc::DataClauseAttr::get(
-                                              builder.getContext(), clause)));
-}
-
 template <typename GlobalOp, typename EntryOp, typename DeclareOp,
           typename ExitOp>
 static void createDeclareGlobalOp(mlir::OpBuilder &modBuilder,
                                   fir::FirOpBuilder &builder,
                                   mlir::Location loc, fir::GlobalOp &globalOp,
                                   mlir::acc::DataClause clause) {
   std::stringstream declareGlobalName;
 
const auto &modifier =
           listWithModifier.t);
   mlir::acc::DataClause dataClause =
       (modifier && (*modifier).v == mod) ? clauseWithModifier : clause;
   genGlobalCtors<EntryOp, ExitOp>(converter, modBuilder, accObjectList,
                                   dataClause);
 }
 
 static void
+genDeclareInFunction(Fortran::lower::AbstractConverter &converter,
+                     Fortran::semantics::SemanticsContext &semanticsContext,
+                     mlir::Location loc,
+                     const Fortran::parser::AccClauseList &accClauseList) {
+  llvm::SmallVector<mlir::Value> dataClauseOperands, copyEntryOperands;
+  Fortran::lower::StatementContext stmtCtx;
+  fir::FirOpBuilder &builder = converter.getFirOpBuilder();
+  for (const Fortran::parser::AccClause &clause : accClauseList.v) {
+    if (const auto *copyClause =
+            std::get_if<Fortran::parser::AccClause::Copy>(&clause.u)) {
+      auto crtDataStart = dataClauseOperands.size();
+
+      genDataOperandOperations<mlir::acc::CopyinOp>(
+          copyClause->v, converter, semanticsContext, stmtCtx,
+          dataClauseOperands, mlir::acc::DataClause::acc_copy,
+          /*structured=*/true, /*setDeclareAttr=*/true);
+      copyEntryOperands.append(dataClauseOperands.begin() + crtDataStart,
+                               dataClauseOperands.end());
+    } else {
+      mlir::Location clauseLocation = converter.genLocation(clause.source);
+      TODO(clauseLocation, "clause on declare directive");
+    }
+  }
+
+  builder.create<mlir::acc::DeclareEnterOp>(loc, dataClauseOperands);
+}
+
+static void
 genDeclareInModule(Fortran::lower::AbstractConverter &converter,
                    mlir::ModuleOp &moduleOp,
                    const Fortran::parser::AccClauseList &accClauseList) {
   mlir::OpBuilder modBuilder(moduleOp.getBodyRegion());
   for (const Fortran::parser::AccClause &clause : accClauseList.v) {
     if (const auto *createClause =
             std::get_if<Fortran::parser::AccClause::Create>(&clause.u)) {
       const Fortran::parser::AccObjectListWithModifier &listWithModifier =

 static void genACC(Fortran::lower::AbstractConverter &converter,
                    Fortran::semantics::SemanticsContext &semanticsContext,
                    Fortran::lower::pft::Evaluation &eval,
                    const Fortran::parser::OpenACCStandaloneDeclarativeConstruct
                        &declareConstruct) {
 
   const auto &declarativeDir =
       std::get<Fortran::parser::AccDeclarativeDirective>(declareConstruct.t);
+  mlir::Location directiveLocation =
+      converter.genLocation(declarativeDir.source);
   const auto &accClauseList =
       std::get<Fortran::parser::AccClauseList>(declareConstruct.t);
 
   if (declarativeDir.v == llvm::acc::Directive::ACCD_declare) {
     fir::FirOpBuilder &builder = converter.getFirOpBuilder();
     auto moduleOp =
         builder.getBlock()->getParent()->getParentOfType<mlir::ModuleOp>();
     auto funcOp =
         builder.getBlock()->getParent()->getParentOfType<mlir::func::FuncOp>();
     if (funcOp)
-      TODO(funcOp.getLoc(), "OpenACC declare in function/subroutine");
+      genDeclareInFunction(converter, semanticsContext, directiveLocation,
+                           accClauseList);
     else if (moduleOp)
       genDeclareInModule(converter, moduleOp, accClauseList);
     return;
   }
   llvm_unreachable("unsupported declarative directive");
 }
 
 void Fortran::lower::genOpenACCConstruct(

flang/test/Lower/OpenACC/acc-declare.f90

 ! CHECK-LABEL: fir.global @_QMacc_declare_device_link_testEdata1 {acc.declare = #acc.declare<dataClause =  acc_declare_link>} : !fir.array<5000xi32> {
 
 ! CHECK-LABEL: acc.global_ctor @_QMacc_declare_device_link_testEdata1_acc_ctor {
 ! CHECK:         %[[GLOBAL_ADDR:.*]] = fir.address_of(@_QMacc_declare_device_link_testEdata1) {acc.declare = #acc.declare<dataClause =  acc_declare_link>} : !fir.ref<!fir.array<5000xi32>>
 ! CHECK:         %[[LINK:.*]] = acc.declare_link varPtr(%[[GLOBAL_ADDR]] : !fir.ref<!fir.array<5000xi32>>) -> !fir.ref<!fir.array<5000xi32>> {name = "data1", structured = false}
 ! CHECK:         acc.declare_enter dataOperands(%[[LINK]] : !fir.ref<!fir.array<5000xi32>>)
 ! CHECK:         acc.terminator
 ! CHECK:       }
+
+module acc_declare
+  contains
+
+  subroutine acc_declare_copy()
+    integer :: a(100), i
+    !$acc declare copy(a)
+
+    do i = 1, 100
+      a(i) = i
+    end do
+  end subroutine
+
+! CHECK-LABEL: func.func @_QMacc_declarePacc_declare_copy()
+! CHECK: %[[ALLOCA:.*]] = fir.alloca !fir.array<100xi32> {acc.declare = #acc.declare<dataClause =  acc_copy>, bindc_name = "a", uniq_name = "_QMacc_declareFacc_declare_copyEa"}
+! CHECK: %[[BOUND:.*]] = acc.bounds   lowerbound(%{{.*}} : index) upperbound(%{{.*}} : index) extent(%{{.*}} : index) stride(%c1 : index) startIdx(%c1 : index)
+! CHECK: %[[COPYIN:.*]] = acc.copyin varPtr(%[[ALLOCA]] : !fir.ref<!fir.array<100xi32>>) bounds(%[[BOUND]]) -> !fir.ref<!fir.array<100xi32>> {dataClause = #acc<data_clause acc_copy>, name = "a"}
+! CHECK: acc.declare_enter dataOperands(%[[COPYIN]] : !fir.ref<!fir.array<100xi32>>)
+
+end module