GPU HIP CMake: Improve CUDA similarity check, avoid unnecessary recheck

Author: davidrohr

GPU/GPUTracking/Base/hip/CMakeLists.txt

@@ -52,7 +52,8 @@ if(NOT DEFINED GPUCA_HIP_HIPIFY_FROM_CUDA OR "${GPUCA_HIP_HIPIFY_FROM_CUDA}")
     list(APPEND HIP_SOURCES "${GPUCA_HIP_SOURCE_DIR}/${HIP_SOURCE}")
   endforeach()
 
-  add_custom_target(${MODULE}_HIPIFIED_CHK COMMAND diff -u ${GPUCA_HIP_SOURCE_DIR}/GPUReconstructionHIPkernel.template.hip ${CMAKE_CURRENT_SOURCE_DIR}/GPUReconstructionHIPkernel.template.hip DEPENDS ${GPUCA_HIP_SOURCE_DIR}/GPUReconstructionHIPkernel.template.hip ${CMAKE_CURRENT_SOURCE_DIR}/GPUReconstructionHIPkernel.template.hip)
+  add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${MODULE}_HIPIFIED_CHK.done COMMAND diff -u ${GPUCA_HIP_SOURCE_DIR}/GPUReconstructionHIPkernel.template.hip ${CMAKE_CURRENT_SOURCE_DIR}/GPUReconstructionHIPkernel.template.hip && touch ${CMAKE_CURRENT_BINARY_DIR}/${MODULE}_HIPIFIED_CHK.done DEPENDS ${GPUCA_HIP_SOURCE_DIR}/GPUReconstructionHIPkernel.template.hip ${CMAKE_CURRENT_SOURCE_DIR}/GPUReconstructionHIPkernel.template.hip)
+  add_custom_target(${MODULE}_HIPIFIED_CHK DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/${MODULE}_HIPIFIED_CHK.done)
 else()
   get_filename_component(GPUCA_HIP_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR} ABSOLUTE)
 endif()