vtkConduitSource: Support mesh data from external memory spaces

Includes the following MRs squashed for easy of rebasing:

commit 695023a3b300ae42fc4ce1fff6042cc7d771969c
Author: Dan Lipsa <[email protected]>
Date:   Thu Oct 31 13:56:35 2024 -0400

    No need for memorySpace parameter

commit cbd3489deab1cd280ea62bef6b36054487db88cf
Author: Dan Lipsa <[email protected]>
Date:   Thu Oct 31 13:12:53 2024 -0400

    Use IsDevicePointer instead of IsDirectAccessPossible

commit 6e749affe252d5dc05ec5aa00d8f1717a974835f
Author: Dan Lipsa <[email protected]>
Date:   Thu Oct 24 20:29:18 2024 -0400

    Add error logging

commit 144af51fc79f82ec832b11e740065c2464452af8
Author: Dan Lipsa <[email protected]>
Date:   Thu Oct 24 16:18:51 2024 -0400

    Use cudaPointerGetAttributes to ask if device or host pointer

commit 9a46db52454719f6ddb4f0595d5ca03e4efdd259
Author: Dan Lipsa <[email protected]>
Date:   Fri Sep 27 09:47:55 2024 -0400

    No conversion for vtkmDataArray

commit b52093c55353e60ba90b3dbe671362fb850b1647
Author: Dan Lipsa <[email protected]>
Date:   Thu Sep 26 10:37:21 2024 -0400

    vtkErrorMacro is not available in a static method

commit c318c5bf89de83ced7294b6f79dd02aecadffce7
Author: Dan Lipsa <[email protected]>
Date:   Thu Sep 5 11:26:15 2024 -0400

    Add vtkConduitArrayUtilities to classes of IOCatalystConduit

commit f84ef340f5a40127f6006e38102ae0dd4b47cd44
Author: Dan Lipsa <[email protected]>
Date:   Thu Sep 5 09:24:36 2024 -0400

    Remove not needed link with catalyst

commit 908563b1ebda7cc47e22d6a4bf92cf5d14a309aa
Author: Jaswant Panchumarti <[email protected]>
Date:   Tue Dec 19 17:45:09 2023 -0500

    vtkConduitSource: Support mesh data from external memory spaces

Documentation/release/dev/add-external-memory-support-for-catalyst-conduit.md

@@ -0,0 +1,8 @@
+## Add external memory support for vtkConduitSource
+
+`vtkConduitSource` can now keep point coordinates, cell connectivity
+and field values from conduit on an accelerator device such as CUDA or
+HIP. This is done by testing pointers in conduit to see if they are
+stored on a device or on the host memory.  Note that you must
+configure and build VTK with VTK-m configured for the appropriate
+device, otherwise data will be transfered to the host memory.

IO/CatalystConduit/CMakeLists.txt

@@ -1,11 +1,47 @@
 set(classes
-  vtkConduitArrayUtilities
   vtkConduitSource
   vtkConduitToDataObject
   vtkDataObjectToConduit)
 
+if (TARGET vtkm::cuda)
+  list(APPEND classes vtkConduitArrayUtilities)
+endif()
+
 vtk_module_add_module(VTK::IOCatalystConduit
-  CLASSES ${classes})
+  CLASSES ${classes}
+  NOWRAP_CLASSES ${nowrap_classes})
+
+if (VTK_KOKKOS_BACKEND STREQUAL "HIP")
+  set(VTK_KOKKOS_BACKEND_HIP 1)
+endif()
+
+configure_file(
+  "${CMAKE_CURRENT_SOURCE_DIR}/vtkDeviceMemoryType.h.in"
+  "${CMAKE_CURRENT_BINARY_DIR}/vtkDeviceMemoryType.h"
+  @ONLY)
+
+
+if (TARGET vtkm::cuda)
+  # Temporarily suppress "has address taken but no possible call to it" warnings,
+  # until we figure out its implications.
+  # We are disabling all warnings as nvlink has no known way to suppress
+  # individual warning types.
+  string(APPEND CMAKE_CUDA_FLAGS " -Xnvlink -w")
+
+  list(TRANSFORM nowrap_classes APPEND ".cxx" OUTPUT_VARIABLE nowrap_sources)
+  set(cuda_impl ${nowrap_sources})
+  set_source_files_properties(${cuda_impl} PROPERTIES LANGUAGE CUDA)
+
+  vtk_module_set_properties(VTK::IOCatalystConduit
+    CUDA_SEPARABLE_COMPILATION ON)
+
+  vtk_module_compile_options(VTK::IOCatalystConduit
+    PUBLIC $<$<COMPILE_LANGUAGE:CUDA>:-Xcudafe --diag_suppress=extra_semicolon>)
+
+  find_package(CUDAToolkit REQUIRED)
+  vtk_module_link(VTK::IOCatalystConduit PRIVATE CUDA::cudart)
+endif ()
+
 
 vtk_add_test_mangling(VTK::IOCatalystConduit)
 add_subdirectory(Catalyst)

IO/CatalystConduit/Testing/Cxx/CMakeLists.txt

@@ -1,15 +1,49 @@
 vtk_add_test_cxx(vtkConduitCxxTests tests
   NO_VALID NO_OUTPUT
   TestDataObjectToConduit.cxx
-  TestConduitSource.cxx)
+  TestConduitSource.cxx
+  TestConduitSourceExternalMemorySpaces.cxx)
 
 vtk_test_cxx_executable(vtkConduitCxxTests tests)
 
 if (TARGET VTK::ParallelMPI)
   vtk_add_test_mpi(vtkConduitCxxTests-MPI mpitests
     TESTING_DATA NO_VALID NO_OUTPUT
     TestDataObjectToConduit.cxx
-    TestConduitSource.cxx)
+    TestConduitSource.cxx
+    TestConduitSourceExternalMemorySpaces.cxx)
 
   vtk_test_cxx_executable(vtkConduitCxxTests-MPI mpitests)
 endif()
+
+if (TARGET vtkm::cuda)
+  foreach(src IN LISTS tests)
+    string(REPLACE "," ";" src ${src})
+    list(GET src 0 src)
+
+    set_source_files_properties(${src} PROPERTIES LANGUAGE CUDA)
+  endforeach()
+
+  #the tests aren't scoped as a child directory of vtkAcceleratorsVTKmDataModel
+  #so we need to redo this logic
+  vtkm_get_cuda_flags(CMAKE_CUDA_FLAGS)
+
+  # Temporarily suppress "has address taken but no possible call to it" warnings,
+  # until we figure out its implications.
+  # We are disabling all warnings as nvlink has no known way to suppress
+  # individual warning types.
+  string(APPEND CMAKE_CUDA_FLAGS " -Xnvlink -w")
+endif()
+
+if (TARGET vtkm::cuda)
+  # When cuda is enabled VTK::AcceleratorsVTKmDataModel is built statically but with fpic
+  # enabled so the tests are also built with fpic enabled
+  set_target_properties(vtkConduitCxxTests PROPERTIES
+    CUDA_ARCHITECTURES OFF
+    POSITION_INDEPENDENT_CODE ON
+    )
+  set_target_properties(vtkConduitCxxTests-MPI PROPERTIES
+    CUDA_ARCHITECTURES OFF
+    POSITION_INDEPENDENT_CODE ON
+    )
+endif()

IO/CatalystConduit/Testing/Cxx/TestConduitSource.cxx

@@ -735,7 +735,6 @@ inline unsigned int GetLinearIndex3D(unsigned int i, unsigned int j, unsigned in
 //----------------------------------------------------------------------------
 void CreateMixedUnstructuredMesh2D(unsigned int npts_x, unsigned int npts_y, conduit_cpp::Node& res)
 {
-  conduit_cpp::Node mesh;
   CreateCoords(npts_x, npts_y, 1, res);
 
   const unsigned int nele_x = npts_x - 1;
@@ -965,7 +964,6 @@ void CreateWedgeAndPyramidUnstructuredMesh(
 void CreateMixedUnstructuredMesh(
   unsigned int nptsX, unsigned int nptsY, unsigned int nptsZ, conduit_cpp::Node& res)
 {
-  conduit_cpp::Node mesh;
   CreateCoords(nptsX, nptsY, nptsZ, res);
 
   res["state/time"] = 3.1415;