Another turn on the wheel to get VTK-m to export CUDA flags

This is a work around while we wait on requiring CMake 3.15 for all
cuda builds. At that point we can replace this with setting
`cuda_architecture_flags` as part of the EXPORT_PROPERTIES of the
vtkm_cuda target.

This has been tested with the ascent proxy

CMake/VTKmConfig.cmake.in

@@ -91,6 +91,13 @@ if(NOT "${CMAKE_BINARY_DIR}" STREQUAL "@VTKm_BINARY_DIR@")
   include(${VTKm_CONFIG_DIR}/VTKmTargets.cmake)
 endif()
 
+# Once we can require CMake 3.15 for all cuda builds we can
+# replace this with setting `cuda_architecture_flags` as part of the
+# EXPORT_PROPERTIES of the vtkm_cuda target
+if(VTKm_ENABLE_CUDA)
+  set_target_properties(vtkm::cuda PROPERTIES cuda_architecture_flags "@VTKm_CUDA_Architecture_Flags@")
+endif()
+
 # VTKm requires some CMake Find modules not included with CMake, so
 # include the CMake modules distributed with VTKm.
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${VTKm_CMAKE_MODULE_PATH})

CMake/VTKmDeviceAdapters.cmake

@@ -247,7 +247,11 @@ if(VTKm_ENABLE_CUDA)
     string(REPLACE ";" " " arch_flags "${arch_flags}")
     set(CMAKE_CUDA_FLAGS "${CMAKE_CUDA_FLAGS} ${arch_flags}")
 
-    set_target_properties(vtkm_cuda PROPERTIES INTERFACE_CUDA_Architecture_Flags "${arch_flags}")
+    # This needs to be lower-case for the property to be properly exported
+    # CMake 3.15 we can add `cuda_architecture_flags` to the EXPORT_PROPERTIES
+    # target property to have this automatically exported for us
+    set_target_properties(vtkm_cuda PROPERTIES cuda_architecture_flags "${arch_flags}")
+    set(VTKm_CUDA_Architecture_Flags "${arch_flags}")
   endif()
 endif()
 

CMake/VTKmWrappers.cmake

@@ -130,7 +130,7 @@ function(vtkm_get_cuda_flags settings_var)
   if(TARGET vtkm::cuda)
     get_property(arch_flags
       TARGET    vtkm::cuda
-      PROPERTY  INTERFACE_CUDA_Architecture_Flags)
+      PROPERTY  cuda_architecture_flags)
     set(${settings_var} "${${settings_var}} ${arch_flags}" PARENT_SCOPE)
   endif()
 endfunction()