Adding support for using Eigen in HIP kernels.

This commit enables the use of Eigen on HIP kernels / AMD GPUs. Support has been added along the same lines as what already exists for using Eigen in CUDA kernels / NVidia GPUs.

Application code needs to explicitly define EIGEN_USE_HIP when using Eigen in HIP kernels. This is because some of the CUDA headers get picked up by default during Eigen compile (irrespective of whether or not the underlying compiler is CUDACC/NVCC, for e.g. Eigen/src/Core/arch/CUDA/Half.h). In order to maintain this behavior, the EIGEN_USE_HIP macro is used to switch to using the HIP version of those header files (see Eigen/Core and unsupported/Eigen/CXX11/Tensor)


Use the "-DEIGEN_TEST_HIP" cmake option to enable the HIP specific unit tests.

test/CMakeLists.txt

@@ -407,6 +407,48 @@ endif(CUDA_FOUND)
 endif(EIGEN_TEST_CUDA)
 
 
+# HIP unit tests
+option(EIGEN_TEST_HIP "Add HIP support." OFF)
+if (EIGEN_TEST_HIP)
+
+  set(HIP_PATH "/opt/rocm/hip" CACHE STRING "Path to the HIP installation.")
+
+  if (EXISTS ${HIP_PATH})
+    
+    list(APPEND CMAKE_MODULE_PATH ${HIP_PATH}/cmake) 
+
+    find_package(HIP REQUIRED)
+    if (HIP_FOUND)
+
+      execute_process(COMMAND ${HIP_PATH}/bin/hipconfig --platform OUTPUT_VARIABLE HIP_PLATFORM)
+
+      if (${HIP_PLATFORM} STREQUAL "hcc")
+
+	include_directories(${CMAKE_CURRENT_BINARY_DIR})
+	include_directories(${HIP_PATH}/include)
+
+	set(EIGEN_ADD_TEST_FILENAME_EXTENSION  "cu")
+	ei_add_test(hip_basic)
+	unset(EIGEN_ADD_TEST_FILENAME_EXTENSION)
+	
+      elseif (${HIP_PLATFORM} STREQUAL "nvcc")
+	message(FATAL_ERROR "HIP_PLATFORM = nvcc is not supported within Eigen")
+      else ()
+	message(FATAL_ERROR "Unknown HIP_PLATFORM = ${HIP_PLATFORM}")
+      endif()
+      
+    endif(HIP_FOUND)
+    
+  else ()
+
+    message(FATAL_ERROR "EIGEN_TEST_HIP is ON, but the specified HIP_PATH (${HIP_PATH}) does not exist")
+    
+  endif()
+    
+endif(EIGEN_TEST_HIP)
+
+
+
 file(MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/failtests)    
 add_test(NAME failtests WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/failtests COMMAND ${CMAKE_COMMAND} ${Eigen_SOURCE_DIR} -G "${CMAKE_GENERATOR}" -DEIGEN_FAILTEST=ON)