[flang-commits] [flang] [llvm] [Flang][OpenMP] Improve use_device_addr code generation (PR #221265)

Dominik Adamski via flang-commits flang-commits at lists.llvm.org
Fri Sep 4 08:54:00 PDT 2026


https://github.com/DominikAdamski created https://github.com/llvm/llvm-project/pull/221265

Currently, the `use_device_addr` implementation reuses the standard mapping mechanism, which is suboptimal for code like:

```
SUBROUTINE device_addr_func(x)
    INTEGER, TARGET, INTENT(IN)    :: x(:)
    !$omp target data use_device_addr (x)
        call
```

For such code, Flang maps the temporary descriptor for the x array to the GPU. This unnecessary mapping is time-consuming and can be a large bottleneck for Fortran-to-C function wrappers that use `use_device_addr` to pass a C pointer for offload code.

For `use_device_addr`, we only need to update the base address in the descriptor that is used inside `use_device_addr`. This is cheaper than mapping the whole descriptor to the GPU.

Scope of changes:

1) Modified mapping for the use_device_addr clause. Map only the descriptor
   and do not check whether it is present on the GPU.
2) Generated a copy of the host descriptor with an updated base address
   for the use_device_addr code region.

>From e8fd8f5fcabc9a093f21728c65ec58acbea625aa Mon Sep 17 00:00:00 2001
From: Dominik Adamski <dominik.adamski at amd.com>
Date: Fri, 4 Sep 2026 10:37:23 -0500
Subject: [PATCH] [Flang][OpenMP] Improve use_device_addr code generation

Currently, the use_device_addr implementation reuses the standard
mapping mechanism, which is suboptimal for code like:

SUBROUTINE device_addr_func(x)
    INTEGER, TARGET, INTENT(IN)    :: x(:)
    !$omp target data use_device_addr (x)

For such code, Flang maps the temporary descriptor for the x array
to the GPU. This unnecessary mapping is time-consuming
and can be a large bottleneck for Fortran-to-C function wrappers
that use use_device_addr to pass a C pointer for offload code.

For use_device_addr, we only need to update the base address
in the descriptor that is used inside use_device_addr. This is cheaper
than mapping the whole descriptor to the GPU.

Scope of changes:

1) Modified mapping for the use_device_addr clause. Map only the descriptor
   and do not check whether it is present on the GPU.
2) Generated a copy of the host descriptor with an updated base address
   for the use_device_addr code region.

Signed-off-by: Dominik Adamski <dominik.adamski at amd.com>
---
 .../Optimizer/OpenMP/MapInfoFinalization.cpp  | 200 +++++++++++++++---
 .../OpenMP/use-device-addr-performance.f90    |  43 ++++
 offload/include/omptarget.h                   |   4 +
 offload/libomptarget/exports                  |   1 +
 offload/libomptarget/interface.cpp            |   7 +
 5 files changed, 222 insertions(+), 33 deletions(-)
 create mode 100644 flang/test/Lower/OpenMP/use-device-addr-performance.f90

diff --git a/flang/lib/Optimizer/OpenMP/MapInfoFinalization.cpp b/flang/lib/Optimizer/OpenMP/MapInfoFinalization.cpp
index e78d194c5c7ae..738064355616a 100644
--- a/flang/lib/Optimizer/OpenMP/MapInfoFinalization.cpp
+++ b/flang/lib/Optimizer/OpenMP/MapInfoFinalization.cpp
@@ -888,14 +888,20 @@ class MapInfoFinalizationPass
     return false;
   }
 
-  bool isUseDeviceAddr(mlir::omp::MapInfoOp mapOp, mlir::Operation &userOp) {
+  mlir::BlockArgument getUseDeviceAddrBlockArg(mlir::omp::MapInfoOp mapOp,
+                                               mlir::Operation &userOp) {
     if (auto targetDataOp = llvm::dyn_cast<mlir::omp::TargetDataOp>(userOp)) {
-      for (mlir::Value uda : targetDataOp.getUseDeviceAddrVars()) {
-        if (uda.getDefiningOp() == mapOp)
-          return true;
+      auto iface = mlir::cast<mlir::omp::BlockArgOpenMPOpInterface>(
+          targetDataOp.getOperation());
+      auto useDeviceAddrArgs = iface.getUseDeviceAddrBlockArgs();
+      auto useDeviceAddrVars = targetDataOp.getUseDeviceAddrVars();
+      for (auto [useDeviceAddrVar, useDeviceAddrArg] :
+           llvm::zip_equal(useDeviceAddrVars, useDeviceAddrArgs)) {
+        if (useDeviceAddrVar.getDefiningOp() == mapOp)
+          return mlir::cast<mlir::BlockArgument>(useDeviceAddrArg);
       }
     }
-    return false;
+    return nullptr;
   }
 
   bool isUseDevicePtr(mlir::omp::MapInfoOp mapOp, mlir::Operation &userOp) {
@@ -1033,10 +1039,11 @@ class MapInfoFinalizationPass
   /// additional attach map which indicates to the runtime to try and attach
   /// the base address to the descriptor if it's available and it's the first
   /// time the ref_ptr has been allocated on the device.
-  void genRefPtrMap(mlir::omp::MapInfoOp op, fir::FirOpBuilder &builder,
-                    mlir::Operation *target, mlir::Value descriptor,
-                    llvm::SmallVectorImpl<ParentAndPlacement> &mapMemberUsers,
-                    bool isAttachNever, bool isAttachAlways) {
+  mlir::omp::MapInfoOp
+  genRefPtrMap(mlir::omp::MapInfoOp op, fir::FirOpBuilder &builder,
+               mlir::Operation *target, mlir::Value descriptor,
+               llvm::SmallVectorImpl<ParentAndPlacement> &mapMemberUsers,
+               bool isAttachNever, bool isAttachAlways) {
     auto newMapInfoOp = mlir::omp::MapInfoOp::create(
         builder, op->getLoc(), op.getResult().getType(), descriptor,
         mlir::TypeAttr::get(fir::unwrapRefType(descriptor.getType())),
@@ -1053,6 +1060,7 @@ class MapInfoFinalizationPass
                            mlir::omp::ClauseMapFlags::ref_ptr, isAttachAlways);
     op.replaceAllUsesWith(newMapInfoOp.getResult());
     op->erase();
+    return newMapInfoOp;
   }
 
   /// Helper function to generate a ref_ptee map. This handles the case where
@@ -1064,11 +1072,12 @@ class MapInfoFinalizationPass
   /// additional attach map which indicates to the runtime to try and attach
   /// the base address to the descriptor if it's available and it's the first
   /// time the ref_ptee has been allocated on the device.
-  void genRefPteeMap(mlir::omp::MapInfoOp op, fir::FirOpBuilder &builder,
-                     mlir::Operation *target, mlir::Value descriptor,
-                     llvm::SmallVectorImpl<ParentAndPlacement> &mapMemberUsers,
-                     bool isAttachNever, bool isAttachAlways,
-                     mlir::FlatSymbolRefAttr mapperId) {
+  mlir::omp::MapInfoOp
+  genRefPteeMap(mlir::omp::MapInfoOp op, fir::FirOpBuilder &builder,
+                mlir::Operation *target, mlir::Value descriptor,
+                llvm::SmallVectorImpl<ParentAndPlacement> &mapMemberUsers,
+                bool isAttachNever, bool isAttachAlways,
+                mlir::FlatSymbolRefAttr mapperId) {
     // NOTE: We replace the descriptor map with the base address map. This
     // effectively replaces the descriptor's index position in any complex
     // structure mapping. This is a little different to the
@@ -1086,6 +1095,7 @@ class MapInfoFinalizationPass
                            newMapInfoOp.getVarPtrPtr());
     op.replaceAllUsesWith(newMapInfoOp.getResult());
     op->erase();
+    return newMapInfoOp;
   }
 
   /// Helper function to generate a ref_ptr_ptee or default descriptor map.
@@ -1096,13 +1106,13 @@ class MapInfoFinalizationPass
   /// a map is generated for the descriptor and its base address,
   /// similarly in the default auto attach case, we generate an additional
   /// attach map.
-  void genRefPtrPteeOrDefaultMap(
+  mlir::omp::MapInfoOp genRefPtrPteeOrDefaultMap(
       mlir::omp::MapInfoOp op, fir::FirOpBuilder &builder,
       mlir::Operation *target, mlir::Value descriptor,
       llvm::SmallVectorImpl<ParentAndPlacement> &mapMemberUsers,
       bool isAttachNever, bool isAttachAlways, bool isHasDeviceAddrFlag,
       bool descCanBeDeferred, bool canOptimizeDescViaPrivatization,
-      mlir::FlatSymbolRefAttr mapperId) {
+      mlir::FlatSymbolRefAttr mapperId, bool mapOnlyDescriptor) {
     bool isRefPtrPtee =
         bitEnumContainsAll(op.getMapType(),
                            mlir::omp::ClauseMapFlags::ref_ptr) &&
@@ -1158,12 +1168,13 @@ class MapInfoFinalizationPass
         /*partial_map=*/builder.getBoolAttr(false));
 
     mlir::Operation *attachMap = nullptr;
-    if (!isAttachNever && !isHasDeviceAddrFlag)
+    if (!isAttachNever && !isHasDeviceAddrFlag && !mapOnlyDescriptor) {
       attachMap =
           genImplicitAttachMap(op, descriptor, mapMemberUsers, target, builder,
                                mlir::omp::ClauseMapFlags::ref_ptr |
                                    mlir::omp::ClauseMapFlags::ref_ptee,
                                isAttachAlways, baseAddr.getVarPtrPtr());
+    }
 
     op.replaceAllUsesWith(newMapInfoOp.getResult());
     op->erase();
@@ -1171,8 +1182,10 @@ class MapInfoFinalizationPass
     // The deferral only applies to cases where we map both the descriptor and
     // base address at once, and when provided ref_ptr_ptee by a user we
     // assume they know what they're asking for and don't intervene.
-    if (descCanBeDeferred && !isRefPtrPtee)
+    if (descCanBeDeferred && !isRefPtrPtee &&
+        !getUseDeviceAddrBlockArg(op, *target))
       deferrableDesc.push_back(std::make_pair(newMapInfoOp, attachMap));
+    return newMapInfoOp;
   }
 
   // This function handles the splitting of allocatable/pointer maps in
@@ -1185,15 +1198,17 @@ class MapInfoFinalizationPass
   // - genRefPteeMap: for ref_ptee mappings
   // - genRefPtrPteeOrDefaultMap: for ref_ptr_ptee or default descriptor
   // mappings
-  void genDescriptorMaps(mlir::omp::MapInfoOp op, fir::FirOpBuilder &builder,
-                         mlir::Operation *target) {
+  mlir::omp::MapInfoOp genDescriptorMaps(mlir::omp::MapInfoOp op,
+                                         fir::FirOpBuilder &builder,
+                                         mlir::Operation *target,
+                                         bool &canOptimizeUseDeviceAddr) {
     bool descCanBeDeferred = false;
     bool canOptimizeDescViaPrivatization = false;
     llvm::SmallVector<ParentAndPlacement> mapMemberUsers;
     getMemberUserList(op, mapMemberUsers);
-
     // TODO: map the addendum segment of the descriptor, similarly to the
     // base address/data pointer member.
+    bool mapOnlyDescriptor = false;
     bool isHasDeviceAddrFlag = isHasDeviceAddr(op, *target);
     bool isAttachNever = bitEnumContainsAll(
         op.getMapType(), mlir::omp::ClauseMapFlags::attach_never);
@@ -1210,11 +1225,24 @@ class MapInfoFinalizationPass
 
     mlir::Value descriptor = getDescriptorFromBoxMap(
         op, builder, descCanBeDeferred, canOptimizeDescViaPrivatization);
+    bool isNewDescriptor = mlir::isa<fir::AllocaOp>(descriptor.getDefiningOp());
+    bool isUseDeviceAddrItem =
+        (getUseDeviceAddrBlockArg(op, *target) != nullptr);
+    bool isArray = false;
+    bool knownRanks = false;
+    fir::BaseBoxType bt = mlir::dyn_cast<fir::BaseBoxType>(
+        fir::unwrapRefType(descriptor.getType()));
+    if (bt) {
+      isArray = bt.isArray();
+      knownRanks = !bt.isAssumedRank();
+    }
+    canOptimizeUseDeviceAddr =
+        (isNewDescriptor && isUseDeviceAddrItem && isArray && knownRanks);
+    mapOnlyDescriptor = isHasDeviceAddrFlag | canOptimizeUseDeviceAddr;
     mlir::FlatSymbolRefAttr mapperId = op.getMapperIdAttr();
-
     // Exclude irregular maps from optimization via privatization; at least for
     // the moment.
-    if (isHasDeviceAddrFlag || isUseDeviceAddr(op, *target) ||
+    if (isHasDeviceAddrFlag || getUseDeviceAddrBlockArg(op, *target) ||
         isUseDevicePtr(op, *target))
       canOptimizeDescViaPrivatization = false;
 
@@ -1234,18 +1262,21 @@ class MapInfoFinalizationPass
     // TODO: This currently only works for the first level of a
     // derived-type descriptor chain and will likely need to be extended for the
     // case where we do a similar style of mapping for deeper nestings.
+    mlir::omp::MapInfoOp newMapInfo;
     if (isRefPtr && op.getMembers().empty()) {
-      genRefPtrMap(op, builder, target, descriptor, mapMemberUsers,
-                   isAttachNever, isAttachAlways);
+      newMapInfo = genRefPtrMap(op, builder, target, descriptor, mapMemberUsers,
+                                isAttachNever, isAttachAlways);
     } else if (isRefPtee) {
-      genRefPteeMap(op, builder, target, descriptor, mapMemberUsers,
-                    isAttachNever, isAttachAlways, mapperId);
+      newMapInfo =
+          genRefPteeMap(op, builder, target, descriptor, mapMemberUsers,
+                        isAttachNever, isAttachAlways, mapperId);
     } else {
-      genRefPtrPteeOrDefaultMap(op, builder, target, descriptor, mapMemberUsers,
-                                isAttachNever, isAttachAlways,
-                                isHasDeviceAddrFlag, descCanBeDeferred,
-                                canOptimizeDescViaPrivatization, mapperId);
+      newMapInfo = genRefPtrPteeOrDefaultMap(
+          op, builder, target, descriptor, mapMemberUsers, isAttachNever,
+          isAttachAlways, mapOnlyDescriptor, descCanBeDeferred,
+          canOptimizeDescViaPrivatization, mapperId, canOptimizeUseDeviceAddr);
     }
+    return newMapInfo;
   }
 
   void addImplicitDescriptorMapToTargetDataOp(mlir::omp::MapInfoOp op,
@@ -1283,7 +1314,7 @@ class MapInfoFinalizationPass
     if (!llvm::isa<mlir::omp::TargetDataOp>(target) || op.getMembers().empty())
       return;
 
-    if (!isUseDeviceAddr(op, target) && !isUseDevicePtr(op, target))
+    if (!getUseDeviceAddrBlockArg(op, target) && !isUseDevicePtr(op, target))
       return;
 
     auto targetDataOp = llvm::cast<mlir::omp::TargetDataOp>(target);
@@ -1404,6 +1435,101 @@ class MapInfoFinalizationPass
     return false;
   }
 
+  mlir::Value genTgtGetMappedPtrCall(fir::FirOpBuilder &builder,
+                                     mlir::Location loc, mlir::Value deviceNum,
+                                     mlir::Value hostPtr,
+                                     mlir::ModuleOp module) {
+    auto *context = builder.getContext();
+    auto voidPtrType = fir::LLVMPointerType::get(context, builder.getI8Type());
+    auto i32Type = builder.getI32Type();
+    auto i64Type = builder.getI64Type();
+    auto funcName = "__tgt_get_mapped_ptr";
+    auto funcOp = module.lookupSymbol<mlir::func::FuncOp>(funcName);
+
+    if (!funcOp) {
+      auto funcType = mlir::FunctionType::get(context, {i64Type, voidPtrType},
+                                              {voidPtrType});
+
+      mlir::OpBuilder::InsertionGuard guard(builder);
+      builder.setInsertionPointToStart(module.getBody());
+
+      funcOp = mlir::func::FuncOp::create(builder, loc, funcName, funcType);
+      funcOp.setPrivate();
+    }
+    if (!deviceNum) {
+      auto funcGetDefaultDeviceName = "omp_get_default_device";
+      auto funcGetDefaultDeviceOp =
+          module.lookupSymbol<mlir::func::FuncOp>(funcGetDefaultDeviceName);
+      if (!funcGetDefaultDeviceOp) {
+        auto funcType = mlir::FunctionType::get(context, {}, {i32Type});
+
+        mlir::OpBuilder::InsertionGuard guard(builder);
+        builder.setInsertionPointToStart(module.getBody());
+
+        funcGetDefaultDeviceOp = mlir::func::FuncOp::create(
+            builder, loc, funcGetDefaultDeviceName, funcType);
+        funcGetDefaultDeviceOp.setPrivate();
+      }
+      auto callGetDefaultDeviceOp =
+          fir::CallOp::create(builder, loc, funcGetDefaultDeviceOp, {});
+      deviceNum = callGetDefaultDeviceOp.getResult(0);
+    }
+    llvm::SmallVector<mlir::Value> args;
+    args.push_back(fir::ConvertOp::create(builder, loc, i64Type, deviceNum));
+    args.push_back(fir::ConvertOp::create(builder, loc, voidPtrType, hostPtr));
+    auto callOp = fir::CallOp::create(builder, loc, funcOp, args);
+    return callOp.getResult(0);
+  }
+
+  void genOptimizedUseDeviceAddr(fir::FirOpBuilder &builder,
+                                 mlir::omp::TargetDataOp targetDataOp,
+                                 mlir::omp::MapInfoOp mapOp,
+                                 mlir::ModuleOp module) {
+    mlir::Location loc = targetDataOp.getLoc();
+    mapOp.setMapType(mapOp.getMapType() | mlir::omp::ClauseMapFlags::literal);
+    auto arg = getUseDeviceAddrBlockArg(mapOp, *targetDataOp.getOperation());
+    auto insertionPoint = builder.saveInsertionPoint();
+    builder.setInsertionPoint(&targetDataOp->getRegion(0).front().front());
+    // We need to create a temporary copy of the host descriptor, which will
+    // be used inside the use_device_addr code region. The copy will be updated
+    // with the target pointer of the mapped array. The lifetime of the
+    // temporary copy is equal to the scope of the use_device_addr.
+    // The additional copy eliminates the need to synchronize the host
+    // descriptor if we want to update the host descriptor inside the
+    // use_device_addr.
+    auto allocaTgtDescriptor =
+        fir::AllocaOp::create(builder, loc, arg.getType());
+    auto allocaHostDescriptor =
+        fir::AllocaOp::create(builder, loc, arg.getType());
+    fir::StoreOp::create(builder, loc, arg, allocaHostDescriptor);
+    auto hostDescriptor =
+        fir::LoadOp::create(builder, loc, allocaHostDescriptor);
+    auto hostAddrPtr = fir::BoxAddrOp::create(builder, loc, hostDescriptor);
+    auto convertedAddr = fir::ConvertOp::create(
+        builder, loc,
+        fir::LLVMPointerType::get(builder.getContext(), builder.getI8Type()),
+        hostAddrPtr);
+    auto newAddr = genTgtGetMappedPtrCall(
+        builder, loc, targetDataOp.getDevice(), convertedAddr, module);
+    auto convertedGPUAddr =
+        fir::ConvertOp::create(builder, loc, hostAddrPtr.getType(), newAddr);
+    llvm::SmallVector<mlir::Value> lbounds;
+    llvm::SmallVector<mlir::Value> extents;
+    llvm::SmallVector<mlir::Value> strides;
+    fir::factory::genDimInfoFromBox(builder, loc, hostDescriptor, &lbounds,
+                                    &extents, &strides);
+    auto newDescriptor =
+        fir::CreateBoxOp::create(builder, loc, hostDescriptor.getType(),
+                                 convertedGPUAddr, lbounds, extents, strides);
+    fir::StoreOp::create(builder, loc, newDescriptor, allocaTgtDescriptor);
+    auto res = fir::LoadOp::create(builder, loc, allocaTgtDescriptor);
+    arg.replaceUsesWithIf(res, [&](mlir::OpOperand &use) {
+      mlir::Operation *user = use.getOwner();
+      return res->isBeforeInBlock(user);
+    });
+    builder.restoreInsertionPoint(insertionPoint);
+  }
+
   // This pass executes on omp::MapInfoOp's containing descriptor based types
   // (allocatables, pointers, assumed shape etc.) and expanding them into
   // multiple omp::MapInfoOp's for each pointer member contained within the
@@ -1659,7 +1785,15 @@ class MapInfoFinalizationPass
           builder.setInsertionPoint(op);
           mlir::Operation *targetUser = getFirstTargetUser(op);
           assert(targetUser && "expected user of map operation was not found");
-          genDescriptorMaps(op, builder, targetUser);
+          auto targetDataOp =
+              llvm::dyn_cast<mlir::omp::TargetDataOp>(*targetUser);
+          bool canOptimizeUseDeviceAddr = false;
+          mlir::omp::MapInfoOp newMapInfo = genDescriptorMaps(
+              op, builder, targetUser, canOptimizeUseDeviceAddr);
+          if (canOptimizeUseDeviceAddr && targetDataOp) {
+            genOptimizedUseDeviceAddr(builder, targetDataOp, newMapInfo,
+                                      module);
+          }
         }
       });
 
diff --git a/flang/test/Lower/OpenMP/use-device-addr-performance.f90 b/flang/test/Lower/OpenMP/use-device-addr-performance.f90
new file mode 100644
index 0000000000000..c4785e7e8a097
--- /dev/null
+++ b/flang/test/Lower/OpenMP/use-device-addr-performance.f90
@@ -0,0 +1,43 @@
+! The "use_device_addr" was added to the "target data" directive in OpenMP 5.0.
+! RUN: %flang_fc1 -emit-hlfir -fopenmp -fopenmp-version=50 %s -o - | FileCheck %s
+! RUN: bbc -emit-hlfir -fopenmp -fopenmp-version=50 %s -o - | FileCheck %s
+! This test primary goal is to check that we update only base addr for
+! arrays used in used_device_addr clause.
+
+!CHECK: func.func @{{.*}}device_addr_default(
+!CHECK: %[[MAP:.*]] = omp.map.info var_ptr(%{{.*}} : !fir.ref<!fir.box<!fir.array<?xi32>>>, !fir.box<!fir.array<?xi32>>) map_clauses(always, to, literal) capture(ByRef) name("x") -> !fir.ref<!fir.array<?xi32>>
+!CHECK: omp.target_data use_device_addr(%[[MAP]] -> %[[ARG:.*]] : !fir.ref<!fir.array<?xi32>>) {
+!CHECK:   %[[ALLOCA_TGT_DESC:.*]] = fir.alloca !fir.box<!fir.array<?xi32>>
+!CHECK:   %[[ALLOCA_HOST_DESC:.*]] = fir.alloca !fir.box<!fir.array<?xi32>>
+!CHECK:   fir.store %[[ARG]] to %[[ALLOCA_HOST_DESC]] : !fir.ref<!fir.box<!fir.array<?xi32>>>
+!CHECK:   %[[LOADED_HOST_DESC:.*]] = fir.load %[[ALLOCA_HOST_DESC]] : !fir.ref<!fir.box<!fir.array<?xi32>>>
+!CHECK:   %[[HOST_ARR_ADDR:.*]] = fir.box_addr %[[LOADED_HOST_DESC]] : (!fir.box<!fir.array<?xi32>>) -> !fir.ref<!fir.array<?xi32>>
+!CHECK:   %[[HOST_ARR_PTR:.*]] = fir.convert %[[HOST_ARR_ADDR]] : (!fir.ref<!fir.array<?xi32>>) -> !fir.llvm_ptr<i8>
+!CHECK:   %[[DEVICE_ID:.*]] = fir.call @omp_get_default_device() : () -> i32
+!CHECK:   %[[DEVICE_ID_CONV:.*]] = fir.convert %[[DEVICE_ID]] : (i32) -> i64
+!CHECK:   %[[PTR_ARG:.*]] = fir.convert %[[HOST_ARR_PTR]] : (!fir.llvm_ptr<i8>) -> !fir.llvm_ptr<i8>
+!CHECK:   %[[TGT_PTR:.*]] = fir.call @__tgt_get_mapped_ptr(%[[DEVICE_ID_CONV]], %[[PTR_ARG]]) : (i64, !fir.llvm_ptr<i8>) -> !fir.llvm_ptr<i8>
+!CHECK:   %[[TGT_PTR_CONV:.*]] = fir.convert %[[TGT_PTR]] : (!fir.llvm_ptr<i8>) -> !fir.ref<!fir.array<?xi32>>
+!CHECK:   %[[C0:.*]] = arith.constant 0 : index
+!CHECK:   %[[ARR_DIMS:.*]]:3 = fir.box_dims %[[LOADED_HOST_DESC]], %[[C0]] : (!fir.box<!fir.array<?xi32>>, index) -> (index, index, index)
+!CHECK:   %[[TGT_DESC:.*]] = fir.create_box %[[TGT_PTR_CONV]] lbs(%[[ARR_DIMS]]#0) extents(%[[ARR_DIMS]]#1) strides(%[[ARR_DIMS]]#2) : (!fir.ref<!fir.array<?xi32>>, index, index, index) -> !fir.box<!fir.array<?xi32>>
+!CHECK:   fir.store %[[TGT_DESC]] to %[[ALLOCA_TGT_DESC]] : !fir.ref<!fir.box<!fir.array<?xi32>>>
+!CHECK:   %[[RES_TGT_DESC:.*]] = fir.load %[[ALLOCA_TGT_DESC]] : !fir.ref<!fir.box<!fir.array<?xi32>>>
+!CHECK:   %[[DECL:.*]] = hlfir.declare %[[RES_TGT_DESC]] {fortran_attrs = #fir.var_attrs<intent_in, target>, uniq_name = "_QFdevice_addr_defaultEx"} : (!fir.box<!fir.array<?xi32>>) -> (!fir.box<!fir.array<?xi32>>, !fir.box<!fir.array<?xi32>>)
+  SUBROUTINE device_addr_default(x)
+    INTEGER, TARGET, INTENT(IN)    :: x(:)
+    !$omp target data use_device_addr (x)
+    !$omp end target data
+  END SUBROUTINE
+
+! Goal: check if we take into account device clause
+!CHECK: func.func @{{.*}}device_addr_device_2(
+!CHECK: omp.target_data device(%[[DEVICE_ID_CONST:.*]] : i32) use_device_addr(%{{.*}} -> %{{.*}} : !fir.ref<!fir.array<?xi32>>)
+!CHECK: %[[DEVICE_ID_CONST_CONV:.*]] = fir.convert %c2_i32 : (i32) -> i64
+!CHECK: %[[TGT_PTR1:.*]] = fir.call @__tgt_get_mapped_ptr(%[[DEVICE_ID_CONST_CONV]], %[[BASE_PTR:.*]]) : (i64, !fir.llvm_ptr<i8>) -> !fir.llvm_ptr<i8>
+  SUBROUTINE device_addr_device_2(x)
+    INTEGER, TARGET, INTENT(IN)    :: x(:)
+    !$omp target data use_device_addr (x) device(2)
+    !$omp end target data
+  END SUBROUTINE
+
diff --git a/offload/include/omptarget.h b/offload/include/omptarget.h
index db9590844b2fd..6bd61036cc4b3 100644
--- a/offload/include/omptarget.h
+++ b/offload/include/omptarget.h
@@ -291,6 +291,7 @@ const char *omp_get_uid_from_device(int DeviceNum);
 int omp_get_initial_device(void);
 size_t omp_get_gprivate_limit(int DeviceNum,
                               omp_access_t AccessGroup = omp_access_cgroup);
+void *omp_get_mapped_ptr(const void *Ptr, int DeviceNum);
 void *omp_target_alloc(size_t Size, int DeviceNum);
 void omp_target_free(void *DevicePtr, int DeviceNum);
 int omp_target_is_present(const void *Ptr, int DeviceNum);
@@ -442,6 +443,9 @@ int __tgt_activate_record_replay(int64_t DeviceId, uint64_t MemorySize,
                                  void *VAddr, bool IsRecord, bool SaveOutput,
                                  bool EmitReport, const char *OutputDirPath);
 
+// Gets mapped device pointer. If device pointer is not found, returns
+// host pointer
+void *__tgt_get_mapped_ptr(int64_t DeviceId, const void *HostPtr);
 // Registers a callback for the RPC server. Expects this function type.
 // unsigned callback(rpc::Server::Port *Port, unsigned NumLanes). See the RPC
 // code for details.
diff --git a/offload/libomptarget/exports b/offload/libomptarget/exports
index 1831c43cc5f29..91d29fe41679c 100644
--- a/offload/libomptarget/exports
+++ b/offload/libomptarget/exports
@@ -5,6 +5,7 @@ VERS1.0 {
     __tgt_register_requires;
     __tgt_register_lib;
     __tgt_unregister_lib;
+    __tgt_get_mapped_ptr;
     __tgt_init_all_rtls;
     __tgt_target_data_begin;
     __tgt_target_data_end;
diff --git a/offload/libomptarget/interface.cpp b/offload/libomptarget/interface.cpp
index 5d7d948711b99..5833925209fee 100644
--- a/offload/libomptarget/interface.cpp
+++ b/offload/libomptarget/interface.cpp
@@ -653,3 +653,10 @@ EXTERN void __tgt_register_rpc_callback(unsigned (*Callback)(void *,
     if (Plugin.is_initialized() && Plugin.getNumDevices() > 0)
       Plugin.getRPCServer().registerCallback(Callback);
 }
+
+EXTERN void *__tgt_get_mapped_ptr(int64_t DeviceId, const void *HostPtr) {
+  void *TargetPtr = omp_get_mapped_ptr(HostPtr, DeviceId);
+  if (!TargetPtr)
+    return const_cast<void *>(HostPtr);
+  return TargetPtr;
+}



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