cmake: move kokkos files into subdirectory

CMakeLists.txt

@@ -1,4 +1,4 @@
-# Copyright 2025 Stanford University, NVIDIA Corporation
+# Copyright 2025 Stanford University, NVIDIA Corporation, Los Alamos National Laboratory
 # SPDX-License-Identifier: Apache-2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -512,8 +512,7 @@ if(REALM_ENABLE_KOKKOS)
   find_package(Kokkos COMPONENTS separable_compilation)
   if (Kokkos_FOUND)
     enable_language(${Kokkos_COMPILE_LANGUAGE})
-    list(APPEND REALM_STATIC_DEPENDS Kokkos)
-    list(APPEND REALM_LIBRARIES Kokkos::kokkoscore)
+    list(APPEND REALM_LIBRARIES realm_kokkos)
   endif()
 endif()
 

cmake/RealmConfig.cmake.in

@@ -1,4 +1,4 @@
-# Copyright 2025 Stanford University, NVIDIA Corporation
+# Copyright 2025 Stanford University, NVIDIA Corporation, Los Alamos National Laboratory
 # SPDX-License-Identifier: Apache-2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -90,7 +90,7 @@ list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}")
 # TODO(cperry): move this to be header only / optional, maybe after the c++ api
 #               is implemented on top of the c api
 if(REALM_USE_KOKKOS)
-  find_dependency(Kokkos)
+  find_dependency(Kokkos COMPONENTS separable_compilation)
 endif()
 
 macro(Realm_load_targets type)

cmake/RealmPackaging.cmake

@@ -1,4 +1,4 @@
-# Copyright 2025 Stanford University, NVIDIA Corporation
+# Copyright 2025 Stanford University, NVIDIA Corporation, Los Alamos National Laboratory
 # SPDX-License-Identifier: Apache-2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -30,6 +30,20 @@ install(
   DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/realm"
 )
 
+# Install the realm_kokkos as well when needed
+if(REALM_USE_KOKKOS)
+  install(
+    TARGETS realm_kokkos
+    EXPORT Realm_targets
+    RUNTIME COMPONENT Realm_runtime
+    LIBRARY COMPONENT Realm_runtime
+    ARCHIVE COMPONENT Realm_devel
+    PUBLIC_HEADER COMPONENT Realm_devel DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/realm"
+    INCLUDES
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/realm"
+  )
+endif()
+
 # Install the realm_gex_wrapper as well if we have to link directly to it
 if(REALM_INSTALL_GASNETEX_WRAPPER)
   install(

src/CMakeLists.txt

@@ -1,4 +1,4 @@
-# Copyright 2025 Stanford University, NVIDIA Corporation
+# Copyright 2025 Stanford University, NVIDIA Corporation, Los Alamos National Laboratory
 # SPDX-License-Identifier: Apache-2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -131,12 +131,7 @@ if(REALM_USE_MPI)
 endif()
 
 if(REALM_USE_KOKKOS)
-  list(APPEND REALM_SOURCES kokkos_interop.cc)
-  set_source_files_properties("${REALM_SOURCE_DIR}/kokkos_interop.cc" 
-      DIRECTORY ${PROJECT_SOURCE_DIR}
-      PROPERTIES
-      LANGUAGE ${Kokkos_COMPILE_LANGUAGE}
-  )
+  add_subdirectory(${REALM_SOURCE_DIR}/kokkos)
 endif()
 
 # Replace me later

src/realm/kokkos/CMakeLists.txt

@@ -0,0 +1,82 @@
+# Copyright 2025 Stanford University, NVIDIA Corporation, Los Alamos National Laboratory
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Kokkos interop library - compiled separately with Kokkos-specific compiler settings
+set(CMAKE_CXX_COMPILER "${Kokkos_CXX_COMPILER}")
+
+set(REALM_KOKKOS_SOURCES
+    kokkos_interop.cc
+)
+
+# if this library is STATIC, the Kokkos INTERFACE options will propagate up
+# and force us to use the same compiler (wrapper) as Kokkos globally.
+add_library(realm_kokkos ${REALM_KOKKOS_SOURCES})
+if(NOT "${Kokkos_COMPILE_LANGUAGE}" STREQUAL "CXX")
+  # explicitly setting it to CXX adds a `-x c++`, which breaks hipcc compilation
+  set_source_files_properties(${REALM_KOKKOS_SOURCES} PROPERTIES LANGUAGE ${Kokkos_COMPILE_LANGUAGE})
+endif()
+kokkos_compilation(SOURCE ${REALM_KOKKOS_SOURCES})
+
+target_compile_features(realm_kokkos PUBLIC cxx_std_${REALM_CXX_STANDARD})
+
+target_include_directories(
+    realm_kokkos
+    PUBLIC
+        $<BUILD_INTERFACE:${REALM_SOURCE_DIR}/..>
+        $<BUILD_INTERFACE:${CMAKE_BINARY_DIR}/include>
+    PRIVATE
+        $<$<TARGET_EXISTS:CUDA::cuda_driver>:${CUDAToolkit_CUPTI_INCLUDE_DIR}>
+        $<$<TARGET_EXISTS:CUDA::cuda_driver>:${CUDAToolkit_INCLUDE_DIR}>
+        $<$<TARGET_EXISTS:hip::host>:${HIP_INCLUDE_DIR}>
+)
+
+# Link privately to Kokkos - this prevents Kokkos from propagating to the rest of the build
+target_link_libraries(realm_kokkos PRIVATE Kokkos::kokkoscore)
+
+# Apply standard compile options
+target_compile_options(
+    realm_kokkos
+    PRIVATE
+        $<$<OR:$<CXX_COMPILER_ID:Clang>,$<CXX_COMPILER_ID:AppleClang>,$<CXX_COMPILER_ID:GNU>>:
+            -Wall
+            -Wextra
+            -Wno-unused-parameter>
+        $<$<CXX_COMPILER_ID:MSVC>:
+            /W4
+            /Zc:alignedNew
+            /utf-8
+            /Zi
+            /permissive-
+            /Zc:tlsGuards
+            /wd4100>
+    PUBLIC
+        $<$<CXX_COMPILER_ID:MSVC>:/Zc:__cplusplus>
+)
+
+# Set visibility properties to match main library
+set_target_properties(
+    realm_kokkos
+    PROPERTIES
+        C_VISIBILITY_PRESET hidden
+        CXX_VISIBILITY_PRESET hidden
+        CUDA_VISIBILITY_PRESET hidden
+        VISIBILITY_INLINES_HIDDEN ON
+        POSITION_INDEPENDENT_CODE ON
+)
+
+# Apply coverage flags if enabled
+if(REALM_ENABLE_COVERAGE AND NOT OPENCPPCOV_PATH)
+    append_coverage_compiler_flags_to_target(realm_kokkos)
+endif()

src/realm/kokkos_interop.cc → src/realm/kokkos/kokkos_interop.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Stanford University, NVIDIA Corporation
+ * Copyright 2025 Stanford University, NVIDIA Corporation, Los Alamos National Laboratory
  * SPDX-License-Identifier: Apache-2.0
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -17,7 +17,7 @@
 
 // Realm+Kokkos interop support
 
-#include "realm/kokkos_interop.h"
+#include "realm/kokkos/kokkos_interop.h"
 
 #include "realm/mutex.h"
 #include "realm/processor.h"

src/realm/runtime_impl.cc

@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 Stanford University, NVIDIA Corporation
+ * Copyright 2025 Stanford University, NVIDIA Corporation, Los Alamos National Laboratory
  * SPDX-License-Identifier: Apache-2.0
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -43,7 +43,7 @@
 #include "realm/transfer/channel_disk.h"
 
 #ifdef REALM_USE_KOKKOS
-#include "realm/kokkos_interop.h"
+#include "realm/kokkos/kokkos_interop.h"
 #endif
 
 #ifdef REALM_USE_NVTX