GPU: propagate architecture name and LTO for ITS

Signed-off-by: Felix Schlepper <felix.schlepper@cern.ch>

Author: f3sch

GPU/GPUTracking/Base/cuda/CMakeLists.txt

@@ -204,4 +204,10 @@ add_library(O2::GPUTrackingCUDAExternalProvider ALIAS GPUTrackingCUDAExternalPro
 set_property(TARGET GPUTrackingCUDAExternalProvider PROPERTY CUDA_SEPARABLE_COMPILATION ON)
 target_compile_definitions(GPUTrackingCUDAExternalProvider PRIVATE $<TARGET_PROPERTY:${targetName},COMPILE_DEFINITIONS>)
 target_include_directories(GPUTrackingCUDAExternalProvider PRIVATE $<TARGET_PROPERTY:${targetName},INCLUDE_DIRECTORIES>)
+# Emit LTO IR next to the sm_XX cubin so consumers that device-link with -dlto
+foreach(CUDA_ARCH ${CMAKE_CUDA_ARCHITECTURES})
+  string(REGEX REPLACE "-.*$" "" CUDA_ARCH_STRIPPED "${CUDA_ARCH}")
+  target_compile_options(GPUTrackingCUDAExternalProvider PRIVATE
+      $<$<COMPILE_LANGUAGE:CUDA>:--generate-code=arch=compute_${CUDA_ARCH_STRIPPED},code=[lto_${CUDA_ARCH_STRIPPED}]>)
+endforeach()
 add_dependencies(GPUTrackingCUDAExternalProvider O2::GPUTracking) # must not depend on GPU backend to avoid cyclic dependencies

cmake/O2AddHipifiedExecutable.cmake

@@ -78,4 +78,9 @@ function(o2_add_hipified_executable baseTargetName)
   o2_add_executable("${baseTargetName}"
                     SOURCES ${HIP_SOURCES}
                     ${FORWARD_ARGS})
+
+  # Export architecture name
+  if(A_TARGETVARNAME)
+    set(${A_TARGETVARNAME} ${${A_TARGETVARNAME}} PARENT_SCOPE)
+  endif()
 endfunction()

cmake/O2AddHipifiedLibrary.cmake

@@ -72,4 +72,9 @@ function(o2_add_hipified_library baseTargetName)
   o2_add_library("${baseTargetName}"
                  SOURCES ${HIP_SOURCES}
                  ${FORWARD_ARGS})
+
+  # Export architecture name
+  if(A_TARGETVARNAME)
+    set(${A_TARGETVARNAME} ${${A_TARGETVARNAME}} PARENT_SCOPE)
+  endif()
 endfunction()