Reland "[Flang][OpenMP] Add lowering support for is_device_ptr clause (#169331)"

flang/lib/Lower/OpenMP/ClauseProcessor.cpp

@@ -44,15 +44,6 @@ mlir::omp::ReductionModifier translateReductionModifier(ReductionModifier mod) {
   return mlir::omp::ReductionModifier::defaultmod;
 }
 
-/// Check for unsupported map operand types.
-static void checkMapType(mlir::Location location, mlir::Type type) {
-  if (auto refType = mlir::dyn_cast<fir::ReferenceType>(type))
-    type = refType.getElementType();
-  if (auto boxType = mlir::dyn_cast_or_null<fir::BoxType>(type))
-    if (!mlir::isa<fir::PointerType>(boxType.getElementType()))
-      TODO(location, "OMPD_target_data MapOperand BoxType");
-}
-
 static mlir::omp::ScheduleModifier
 translateScheduleModifier(const omp::clause::Schedule::OrderingModifier &m) {
   switch (m) {
@@ -211,18 +202,6 @@ getIfClauseOperand(lower::AbstractConverter &converter,
                                     ifVal);
 }
 
-static void addUseDeviceClause(
-    lower::AbstractConverter &converter, const omp::ObjectList &objects,
-    llvm::SmallVectorImpl<mlir::Value> &operands,
-    llvm::SmallVectorImpl<const semantics::Symbol *> &useDeviceSyms) {
-  genObjectList(objects, converter, operands);
-  for (mlir::Value &operand : operands)
-    checkMapType(operand.getLoc(), operand.getType());
-
-  for (const omp::Object &object : objects)
-    useDeviceSyms.push_back(object.sym());
-}
-
 //===----------------------------------------------------------------------===//
 // ClauseProcessor unique clauses
 //===----------------------------------------------------------------------===//
@@ -1225,14 +1204,26 @@ bool ClauseProcessor::processInReduction(
 }
 
 bool ClauseProcessor::processIsDevicePtr(
-    mlir::omp::IsDevicePtrClauseOps &result,
+    lower::StatementContext &stmtCtx, mlir::omp::IsDevicePtrClauseOps &result,
     llvm::SmallVectorImpl<const semantics::Symbol *> &isDeviceSyms) const {
-  return findRepeatableClause<omp::clause::IsDevicePtr>(
-      [&](const omp::clause::IsDevicePtr &devPtrClause,
-          const parser::CharBlock &) {
-        addUseDeviceClause(converter, devPtrClause.v, result.isDevicePtrVars,
-                           isDeviceSyms);
+  std::map<Object, OmpMapParentAndMemberData> parentMemberIndices;
+  bool clauseFound = findRepeatableClause<omp::clause::IsDevicePtr>(
+      [&](const omp::clause::IsDevicePtr &clause,
+          const parser::CharBlock &source) {
+        mlir::Location location = converter.genLocation(source);
+        // Force a map so the descriptor is materialized on the device with the
+        // device address inside.
+        mlir::omp::ClauseMapFlags mapTypeBits =
+            mlir::omp::ClauseMapFlags::is_device_ptr |
+            mlir::omp::ClauseMapFlags::to;
+        processMapObjects(stmtCtx, location, clause.v, mapTypeBits,
+                          parentMemberIndices, result.isDevicePtrVars,
+                          isDeviceSyms);
       });
+
+  insertChildMapInfoIntoParent(converter, semaCtx, stmtCtx, parentMemberIndices,
+                               result.isDevicePtrVars, isDeviceSyms);
+  return clauseFound;
 }
 
 bool ClauseProcessor::processLinear(mlir::omp::LinearClauseOps &result) const {

flang/lib/Lower/OpenMP/ClauseProcessor.h

@@ -134,7 +134,7 @@ class ClauseProcessor {
       mlir::Location currentLocation, mlir::omp::InReductionClauseOps &result,
       llvm::SmallVectorImpl<const semantics::Symbol *> &outReductionSyms) const;
   bool processIsDevicePtr(
-      mlir::omp::IsDevicePtrClauseOps &result,
+      lower::StatementContext &stmtCtx, mlir::omp::IsDevicePtrClauseOps &result,
       llvm::SmallVectorImpl<const semantics::Symbol *> &isDeviceSyms) const;
   bool processLinear(mlir::omp::LinearClauseOps &result) const;
   bool

flang/lib/Lower/OpenMP/OpenMP.cpp

@@ -1671,7 +1671,7 @@ static void genTargetClauses(
     hostEvalInfo->collectValues(clauseOps.hostEvalVars);
   }
   cp.processIf(llvm::omp::Directive::OMPD_target, clauseOps);
-  cp.processIsDevicePtr(clauseOps, isDevicePtrSyms);
+  cp.processIsDevicePtr(stmtCtx, clauseOps, isDevicePtrSyms);
   cp.processMap(loc, stmtCtx, clauseOps, llvm::omp::Directive::OMPD_unknown,
                 &mapSyms);
   cp.processNowait(clauseOps);
@@ -2487,13 +2487,15 @@ static bool isDuplicateMappedSymbol(
     const semantics::Symbol &sym,
     const llvm::SetVector<const semantics::Symbol *> &privatizedSyms,
     const llvm::SmallVectorImpl<const semantics::Symbol *> &hasDevSyms,
-    const llvm::SmallVectorImpl<const semantics::Symbol *> &mappedSyms) {
+    const llvm::SmallVectorImpl<const semantics::Symbol *> &mappedSyms,
+    const llvm::SmallVectorImpl<const semantics::Symbol *> &isDevicePtrSyms) {
   llvm::SmallVector<const semantics::Symbol *> concatSyms;
   concatSyms.reserve(privatizedSyms.size() + hasDevSyms.size() +
-                     mappedSyms.size());
+                     mappedSyms.size() + isDevicePtrSyms.size());
   concatSyms.append(privatizedSyms.begin(), privatizedSyms.end());
   concatSyms.append(hasDevSyms.begin(), hasDevSyms.end());
   concatSyms.append(mappedSyms.begin(), mappedSyms.end());
+  concatSyms.append(isDevicePtrSyms.begin(), isDevicePtrSyms.end());
 
   auto checkSymbol = [&](const semantics::Symbol &checkSym) {
     return std::any_of(concatSyms.begin(), concatSyms.end(),
@@ -2533,6 +2535,38 @@ genTargetOp(lower::AbstractConverter &converter, lower::SymMap &symTable,
                    loc, clauseOps, defaultMaps, hasDeviceAddrSyms,
                    isDevicePtrSyms, mapSyms);
 
+  if (!isDevicePtrSyms.empty()) {
+    // is_device_ptr maps get duplicated so the clause and synthesized
+    // has_device_addr entry each own a unique MapInfoOp user, keeping
+    // MapInfoFinalization happy while still wiring the symbol into
+    // has_device_addr when the user didn’t spell it explicitly.
+    auto insertionPt = firOpBuilder.saveInsertionPoint();
+    auto alreadyPresent = [&](const semantics::Symbol *sym) {
+      return llvm::any_of(hasDeviceAddrSyms, [&](const semantics::Symbol *s) {
+        return s && sym && s->GetUltimate() == sym->GetUltimate();
+      });
+    };
+
+    for (auto [idx, sym] : llvm::enumerate(isDevicePtrSyms)) {
+      mlir::Value mapVal = clauseOps.isDevicePtrVars[idx];
+      assert(sym && "expected symbol for is_device_ptr");
+      assert(mapVal && "expected map value for is_device_ptr");
+      auto mapInfo = mapVal.getDefiningOp<mlir::omp::MapInfoOp>();
+      assert(mapInfo && "expected map info op");
+
+      if (!alreadyPresent(sym)) {
+        clauseOps.hasDeviceAddrVars.push_back(mapVal);
+        hasDeviceAddrSyms.push_back(sym);
+      }
+
+      firOpBuilder.setInsertionPointAfter(mapInfo);
+      mlir::Operation *clonedOp = firOpBuilder.clone(*mapInfo.getOperation());
+      auto clonedMapInfo = mlir::cast<mlir::omp::MapInfoOp>(clonedOp);
+      clauseOps.isDevicePtrVars[idx] = clonedMapInfo.getResult();
+    }
+    firOpBuilder.restoreInsertionPoint(insertionPt);
+  }
+
   DataSharingProcessor dsp(converter, semaCtx, item->clauses, eval,
                            /*shouldCollectPreDeterminedSymbols=*/
                            lower::omp::isLastItemInQueue(item, queue),
@@ -2572,7 +2606,7 @@ genTargetOp(lower::AbstractConverter &converter, lower::SymMap &symTable,
       return;
 
     if (!isDuplicateMappedSymbol(sym, dsp.getAllSymbolsToPrivatize(),
-                                 hasDeviceAddrSyms, mapSyms)) {
+                                 hasDeviceAddrSyms, mapSyms, isDevicePtrSyms)) {
       if (const auto *details =
               sym.template detailsIf<semantics::HostAssocDetails>())
         converter.copySymbolBinding(details->symbol(), sym);

flang/test/Integration/OpenMP/map-types-and-sizes.f90

@@ -33,6 +33,15 @@ subroutine mapType_array
   !$omp end target
 end subroutine mapType_array
 
+!CHECK: @.offload_sizes{{.*}} = private unnamed_addr constant [1 x i64] [i64 8]
+!CHECK: @.offload_maptypes{{.*}} = private unnamed_addr constant [1 x i64] [i64 33]
+subroutine mapType_is_device_ptr
+  use iso_c_binding, only : c_ptr
+  type(c_ptr) :: p
+  !$omp target is_device_ptr(p)
+  !$omp end target
+end subroutine mapType_is_device_ptr
+
 !CHECK: @.offload_sizes{{.*}} = private unnamed_addr constant [5 x i64] [i64 0, i64 0, i64 0, i64 8, i64 0]
 !CHECK: @.offload_maptypes{{.*}} = private unnamed_addr constant [5 x i64] [i64 32, i64 281474976711173, i64 281474976711173, i64 281474976711171, i64 281474976711187]
 subroutine mapType_ptr

flang/test/Lower/OpenMP/target.f90

@@ -566,6 +566,36 @@ subroutine omp_target_device_addr
 end subroutine omp_target_device_addr
 
 
+!===============================================================================
+! Target `is_device_ptr` clause
+!===============================================================================
+
+!CHECK-LABEL: func.func @_QPomp_target_is_device_ptr() {
+subroutine omp_target_is_device_ptr
+   use iso_c_binding, only: c_ptr
+   implicit none
+   integer :: i
+   integer :: arr(4)
+   type(c_ptr) :: p
+
+   i = 0
+   arr = 0
+
+   !CHECK: %[[P_STORAGE:.*]] = omp.map.info {{.*}}{name = "p"}
+   !CHECK: %[[P_IS:.*]] = omp.map.info {{.*}}{name = "p"}
+   !CHECK: %[[ARR_MAP:.*]] = omp.map.info {{.*}}{name = "arr"}
+   !CHECK: omp.target is_device_ptr(%[[P_IS]] :
+   !CHECK-SAME: has_device_addr(%[[P_STORAGE]] ->
+   !CHECK-SAME: map_entries({{.*}}%[[ARR_MAP]] ->
+   !$omp target is_device_ptr(p)
+      i = i + 1
+      arr(1) = i
+   !$omp end target
+   !CHECK: omp.terminator
+   !CHECK: }
+end subroutine omp_target_is_device_ptr
+
+
 !===============================================================================
 ! Target Data with unstructured code
 !===============================================================================

mlir/include/mlir/Dialect/OpenMP/OpenMPEnums.td

@@ -128,6 +128,7 @@ def ClauseMapFlagsAttachAuto : I32BitEnumAttrCaseBit<"attach_auto", 15>;
 def ClauseMapFlagsRefPtr : I32BitEnumAttrCaseBit<"ref_ptr", 16>;
 def ClauseMapFlagsRefPtee : I32BitEnumAttrCaseBit<"ref_ptee", 17>;
 def ClauseMapFlagsRefPtrPtee : I32BitEnumAttrCaseBit<"ref_ptr_ptee", 18>;
+def ClauseMapFlagsIsDevicePtr : I32BitEnumAttrCaseBit<"is_device_ptr", 19>;
 
 def ClauseMapFlags : OpenMP_BitEnumAttr<
     "ClauseMapFlags",
@@ -151,7 +152,8 @@ def ClauseMapFlags : OpenMP_BitEnumAttr<
       ClauseMapFlagsAttachAuto,
       ClauseMapFlagsRefPtr,
       ClauseMapFlagsRefPtee,
-      ClauseMapFlagsRefPtrPtee
+      ClauseMapFlagsRefPtrPtee,
+      ClauseMapFlagsIsDevicePtr
     ]>;
 
 def ClauseMapFlagsAttr : OpenMP_EnumAttr<ClauseMapFlags,

mlir/lib/Dialect/OpenMP/IR/OpenMPDialect.cpp

@@ -1818,6 +1818,9 @@ static ParseResult parseMapClause(OpAsmParser &parser,
     if (mapTypeMod == "ref_ptr_ptee")
       mapTypeBits |= ClauseMapFlags::ref_ptr_ptee;
 
+    if (mapTypeMod == "is_device_ptr")
+      mapTypeBits |= ClauseMapFlags::is_device_ptr;
+
     return success();
   };
 
@@ -1887,6 +1890,8 @@ static void printMapClause(OpAsmPrinter &p, Operation *op,
     mapTypeStrs.push_back("ref_ptee");
   if (mapTypeToBool(mapFlags, ClauseMapFlags::ref_ptr_ptee))
     mapTypeStrs.push_back("ref_ptr_ptee");
+  if (mapTypeToBool(mapFlags, ClauseMapFlags::is_device_ptr))
+    mapTypeStrs.push_back("is_device_ptr");
   if (mapFlags == ClauseMapFlags::none)
     mapTypeStrs.push_back("none");
 

mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp

@@ -332,10 +332,6 @@ static LogicalResult checkImplementationStatus(Operation &op) {
         op.getInReductionSyms())
       result = todo("in_reduction");
   };
-  auto checkIsDevicePtr = [&todo](auto op, LogicalResult &result) {
-    if (!op.getIsDevicePtrVars().empty())
-      result = todo("is_device_ptr");
-  };
   auto checkNowait = [&todo](auto op, LogicalResult &result) {
     if (op.getNowait())
       result = todo("nowait");
@@ -435,7 +431,6 @@ static LogicalResult checkImplementationStatus(Operation &op) {
         checkBare(op, result);
         checkDevice(op, result);
         checkInReduction(op, result);
-        checkIsDevicePtr(op, result);
       })
       .Default([](Operation &) {
         // Assume all clauses for an operation can be translated unless they are
@@ -3986,6 +3981,9 @@ convertClauseMapFlags(omp::ClauseMapFlags mlirFlags) {
   auto mapTypeToBool = [&mlirFlags](omp::ClauseMapFlags flag) {
     return (mlirFlags & flag) == flag;
   };
+  const bool hasExplicitMap =
+      (mlirFlags & ~omp::ClauseMapFlags::is_device_ptr) !=
+      omp::ClauseMapFlags::none;
 
   llvm::omp::OpenMPOffloadMappingFlags mapType =
       llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_NONE;
@@ -4026,6 +4024,12 @@ convertClauseMapFlags(omp::ClauseMapFlags mlirFlags) {
   if (mapTypeToBool(omp::ClauseMapFlags::attach))
     mapType |= llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_ATTACH;
 
+  if (mapTypeToBool(omp::ClauseMapFlags::is_device_ptr)) {
+    mapType |= llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_TARGET_PARAM;
+    if (!hasExplicitMap)
+      mapType |= llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_LITERAL;
+  }
+
   return mapType;
 }
 
@@ -4149,6 +4153,9 @@ static void collectMapDataFromMapOperands(
     llvm::Value *origValue = moduleTranslation.lookupValue(offloadPtr);
     auto mapType = convertClauseMapFlags(mapOp.getMapType());
     auto mapTypeAlways = llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_ALWAYS;
+    bool isDevicePtr =
+        (mapOp.getMapType() & omp::ClauseMapFlags::is_device_ptr) !=
+        omp::ClauseMapFlags::none;
 
     mapData.OriginalValue.push_back(origValue);
     mapData.BasePointers.push_back(origValue);
@@ -4175,14 +4182,18 @@ static void collectMapDataFromMapOperands(
         mapData.Mappers.push_back(nullptr);
       }
     } else {
+      // For is_device_ptr we need the map type to propagate so the runtime
+      // can materialize the device-side copy of the pointer container.
       mapData.Types.push_back(
-          llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_LITERAL);
+          isDevicePtr ? mapType
+                      : llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_LITERAL);
       mapData.Mappers.push_back(nullptr);
     }
     mapData.Names.push_back(LLVM::createMappingInformation(
         mapOp.getLoc(), *moduleTranslation.getOpenMPBuilder()));
     mapData.DevicePointers.push_back(
-        llvm::OpenMPIRBuilder::DeviceInfoTy::Address);
+        isDevicePtr ? llvm::OpenMPIRBuilder::DeviceInfoTy::Pointer
+                    : llvm::OpenMPIRBuilder::DeviceInfoTy::Address);
     mapData.IsAMapping.push_back(false);
     mapData.IsAMember.push_back(checkIsAMember(hasDevAddrOperands, mapOp));
   }

mlir/test/Target/LLVMIR/omptarget-llvm.mlir

@@ -622,3 +622,20 @@ module attributes {omp.target_triples = ["amdgcn-amd-amdhsa"]} {
 // CHECK:         br label %[[VAL_40]]
 // CHECK:       omp.done:                                         ; preds = %[[VAL_68]], %[[VAL_63]], %[[VAL_32]]
 // CHECK:         ret void
+
+// -----
+
+module attributes {omp.target_triples = ["amdgcn-amd-amdhsa"]} {
+  llvm.func @_QPomp_target_is_device_ptr(%arg0 : !llvm.ptr) {
+    %map = omp.map.info var_ptr(%arg0 : !llvm.ptr, !llvm.ptr)
+        map_clauses(is_device_ptr) capture(ByRef) -> !llvm.ptr {name = ""}
+    omp.target map_entries(%map -> %ptr_arg : !llvm.ptr) {
+      omp.terminator
+    }
+    llvm.return
+  }
+}
+
+// CHECK: @.offload_sizes = private unnamed_addr constant [1 x i64] [i64 8]
+// CHECK: @.offload_maptypes = private unnamed_addr constant [1 x i64] [i64 288]
+// CHECK-LABEL: define void @_QPomp_target_is_device_ptr

mlir/test/Target/LLVMIR/openmp-todo.mlir

@@ -212,17 +212,6 @@ llvm.func @target_in_reduction(%x : !llvm.ptr) {
 
 // -----
 
-llvm.func @target_is_device_ptr(%x : !llvm.ptr) {
-  // expected-error@below {{not yet implemented: Unhandled clause is_device_ptr in omp.target operation}}
-  // expected-error@below {{LLVM Translation failed for operation: omp.target}}
-  omp.target is_device_ptr(%x : !llvm.ptr) {
-    omp.terminator
-  }
-  llvm.return
-}
-
-// -----
-
 llvm.func @target_enter_data_depend(%x: !llvm.ptr) {
   // expected-error@below {{not yet implemented: Unhandled clause depend in omp.target_enter_data operation}}
   // expected-error@below {{LLVM Translation failed for operation: omp.target_enter_data}}