[flang][OpenACC] Lower init/shutdown directive

[clementval]

Summary

This patch adds lowering for the !$acc init and !$acc shutdown
from the PFT to OpenACC dialect.

This patch is part of the upstreaming effort from fir-dev branch.

Depends on D122384

[PeteSteinfeld]

All builds and tests correctly and looks good.

flang/lib/Lower/OpenACC.cpp

 #include "flang/Optimizer/Builder/FIRBuilder.h"
 #include "flang/Parser/parse-tree.h"
 #include "flang/Semantics/tools.h"
 #include "mlir/Dialect/OpenACC/OpenACC.h"
 #include "llvm/Frontend/OpenACC/ACC.h.inc"
 
 using namespace mlir;
 
+// Special value for * passed in device_type or gang clauses.
+static constexpr std::int64_t starCst{-1};
+
 static const Fortran::parser::Name *
 getDesignatorNameIfDataRef(const Fortran::parser::Designator &designator) {
   const auto *dataRef{std::get_if<Fortran::parser::DataRef>(&designator.u)};
   return dataRef ? std::get_if<Fortran::parser::Name>(&dataRef->u) : nullptr;
 }
 
 static void genObjectList(const Fortran::parser::AccObjectList &objectList,
                           Fortran::lower::AbstractConverter &converter,
static void genAsyncClause(Fortran::lower::AbstractConverter &converter,
   if (asyncClauseValue) { // async has a value.
     async = fir::getBase(converter.genExprValue(
         *Fortran::semantics::GetExpr(*asyncClauseValue), stmtCtx));
   } else {
     addAsyncAttr = true;
   }
 }
 
+static void genDeviceTypeClause(
+    Fortran::lower::AbstractConverter &converter,
+    const Fortran::parser::AccClause::DeviceType *deviceTypeClause,
+    SmallVectorImpl<mlir::Value> &operands,
+    Fortran::lower::StatementContext &stmtCtx) {
+  const auto &deviceTypeValue = deviceTypeClause->v;
+  if (deviceTypeValue) {
+    for (const auto &scalarIntExpr : *deviceTypeValue) {
+      mlir::Value expr = fir::getBase(converter.genExprValue(
+          *Fortran::semantics::GetExpr(scalarIntExpr), stmtCtx));
+      operands.push_back(expr);
+    }
+  } else {
+    fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+    // * was passed as value and will be represented as a special constant.
+    mlir::Value star = firOpBuilder.createIntegerConstant(
+        converter.getCurrentLocation(), firOpBuilder.getIndexType(), starCst);
+    operands.push_back(star);
+  }
+}
+
 static void genIfClause(Fortran::lower::AbstractConverter &converter,
                         const Fortran::parser::AccClause::If *ifClause,
                         mlir::Value &ifCond,
                         Fortran::lower::StatementContext &stmtCtx) {
   fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
   Value cond = fir::getBase(converter.genExprValue(
       *Fortran::semantics::GetExpr(ifClause->v), stmtCtx));
   ifCond = firOpBuilder.createConvert(converter.getCurrentLocation(),
if (addFinalizeAttr)
     exitDataOp.finalizeAttr(firOpBuilder.getUnitAttr());
 }
 
 template <typename Op>
 static void
 genACCInitShutdownOp(Fortran::lower::AbstractConverter &converter,
                      const Fortran::parser::AccClauseList &accClauseList) {
   mlir::Value ifCond, deviceNum;
-  SmallVector<Value, 2> deviceTypeOperands;
+  SmallVector<mlir::Value> deviceTypeOperands;
 
-  auto &firOpBuilder = converter.getFirOpBuilder();
-  auto currentLocation = converter.getCurrentLocation();
+  fir::FirOpBuilder &firOpBuilder = converter.getFirOpBuilder();
+  mlir::Location currentLocation = converter.getCurrentLocation();
   Fortran::lower::StatementContext stmtCtx;
 
   // Lower clauses values mapped to operands.
   // Keep track of each group of operands separatly as clauses can appear
   // more than once.
-  for (const auto &clause : accClauseList.v) {
+  for (const Fortran::parser::AccClause &clause : accClauseList.v) {
     if (const auto *ifClause =
             std::get_if<Fortran::parser::AccClause::If>(&clause.u)) {
-      mlir::Value cond = fir::getBase(converter.genExprValue(
-          *Fortran::semantics::GetExpr(ifClause->v), stmtCtx));
-      ifCond = firOpBuilder.createConvert(currentLocation,
-                                          firOpBuilder.getI1Type(), cond);
+      genIfClause(converter, ifClause, ifCond, stmtCtx);
     } else if (const auto *deviceNumClause =
                    std::get_if<Fortran::parser::AccClause::DeviceNum>(
                        &clause.u)) {
       deviceNum = fir::getBase(converter.genExprValue(
           *Fortran::semantics::GetExpr(deviceNumClause->v), stmtCtx));
     } else if (const auto *deviceTypeClause =
                    std::get_if<Fortran::parser::AccClause::DeviceType>(
                        &clause.u)) {
-
-      const auto &deviceTypeValue = deviceTypeClause->v;
-      if (deviceTypeValue) {
-        for (const auto &scalarIntExpr : *deviceTypeValue) {
-          mlir::Value expr = fir::getBase(converter.genExprValue(
-              *Fortran::semantics::GetExpr(scalarIntExpr), stmtCtx));
-          deviceTypeOperands.push_back(expr);
-        }
-      } else {
-        // * was passed as value and will be represented as a -1 constant
-        // integer.
-        mlir::Value star = firOpBuilder.createIntegerConstant(
-            currentLocation, firOpBuilder.getIntegerType(32), /* STAR */ -1);
-        deviceTypeOperands.push_back(star);
-      }
+      genDeviceTypeClause(converter, deviceTypeClause, deviceTypeOperands,
+                          stmtCtx);
     }
   }
 
   // Prepare the operand segement size attribute and the operands value range.
   SmallVector<mlir::Value, 6> operands;
   SmallVector<int32_t, 3> operandSegments;
   addOperands(operands, operandSegments, deviceTypeOperands);
   addOperand(operands, operandSegments, deviceNum);

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

+! This test checks lowering of OpenACC init directive.
+
+! RUN: bbc -fopenacc -emit-fir %s -o - | FileCheck %s
+
+subroutine acc_init
+  logical :: ifCondition = .TRUE.
+
+  !$acc init
+!CHECK: acc.init{{$}}
+
+  !$acc init if(.true.)
+!CHECK: [[IF1:%.*]] = arith.constant true
+!CHECK: acc.init if([[IF1]]){{$}}
+
+  !$acc init if(ifCondition)
+!CHECK: [[IFCOND:%.*]] = fir.load %{{.*}} : !fir.ref<!fir.logical<4>>
+!CHECK: [[IF2:%.*]] = fir.convert [[IFCOND]] : (!fir.logical<4>) -> i1
+!CHECK: acc.init if([[IF2]]){{$}}
+
+  !$acc init device_num(1)
+!CHECK: [[DEVNUM:%.*]] = arith.constant 1 : i32
+!CHECK: acc.init device_num([[DEVNUM]] : i32){{$}}
+
+  !$acc init device_num(1) device_type(1, 2)
+!CHECK: [[DEVNUM:%.*]] = arith.constant 1 : i32
+!CHECK: [[DEVTYPE1:%.*]] = arith.constant 1 : i32
+!CHECK: [[DEVTYPE2:%.*]] = arith.constant 2 : i32
+!CHECK: acc.init device_type([[DEVTYPE1]], [[DEVTYPE2]] : i32, i32) device_num([[DEVNUM]] : i32){{$}}
+
+end subroutine acc_init
 No newline at end of file

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

+! This test checks lowering of OpenACC shutdown directive.
+
+! RUN: bbc -fopenacc -emit-fir %s -o - | FileCheck %s
+
+subroutine acc_shutdown
+  logical :: ifCondition = .TRUE.
+
+  !$acc shutdown
+!CHECK: acc.shutdown{{$}}
+
+  !$acc shutdown if(.true.)
+!CHECK: [[IF1:%.*]] = arith.constant true
+!CHECK: acc.shutdown if([[IF1]]){{$}}
+
+  !$acc shutdown if(ifCondition)
+!CHECK: [[IFCOND:%.*]] = fir.load %{{.*}} : !fir.ref<!fir.logical<4>>
+!CHECK: [[IF2:%.*]] = fir.convert [[IFCOND]] : (!fir.logical<4>) -> i1
+!CHECK: acc.shutdown if([[IF2]]){{$}}
+
+  !$acc shutdown device_num(1)
+!CHECK: [[DEVNUM:%.*]] = arith.constant 1 : i32
+!CHECK: acc.shutdown device_num([[DEVNUM]] : i32){{$}}
+
+  !$acc shutdown device_num(1) device_type(1, 2)
+!CHECK: [[DEVNUM:%.*]] = arith.constant 1 : i32
+!CHECK: [[DEVTYPE1:%.*]] = arith.constant 1 : i32
+!CHECK: [[DEVTYPE2:%.*]] = arith.constant 2 : i32
+!CHECK: acc.shutdown device_type([[DEVTYPE1]], [[DEVTYPE2]] : i32, i32) device_num([[DEVNUM]] : i32){{$}}
+
+end subroutine acc_shutdown
 No newline at end of file