[llvm] [OFFLOAD] Add plugin with support for Intel oneAPI Level Zero (PR #158900)

[Joseph Huber via llvm-commits]

================
@@ -0,0 +1,54 @@
+# Create the library and add the default arguments.
+add_target_library(omptarget.rtl.level_zero LEVEL_ZERO)
+
+set(LEVEL_ZERO_SRC_FILES
+  src/L0Context.cpp
+  src/L0Device.cpp
+  src/L0Kernel.cpp
+  src/L0Memory.cpp
+  src/L0Program.cpp
+  src/L0Plugin.cpp
+  src/L0Program.cpp
+  src/L0Options.cpp
+)
+
+target_sources(omptarget.rtl.level_zero PRIVATE
+  ${LEVEL_ZERO_SRC_FILES}
+)
+
+target_include_directories(omptarget.rtl.level_zero PRIVATE
+  ${CMAKE_CURRENT_SOURCE_DIR}/include
+)
+
+target_include_directories(omptarget.rtl.level_zero PRIVATE
+  ${LIBOMPTARGET_INCLUDE_DIR}
+  ${LIBOMPTARGET_DEP_LEVEL_ZERO_INCLUDE_DIR}
+  ${LIBOMPTARGET_LLVM_INCLUDE_DIRS}
+  ${LIBOMPTARGET_OMP_HEADER_DIR}
+)
+
+cmake_path(GET LIBOMPTARGET_DEP_LEVEL_ZERO_LIBRARY FILENAME LEVEL_ZERO_LIBRARY_NAME)
+if (EXISTS ${LIBOMPTARGET_DEP_LEVEL_ZERO_LIBRARY} AND NOT "level_zero" IN_LIST LIBOMPTARGET_DLOPEN_PLUGINS)
+  message(STATUS "Building Level Zero NG plugin linked against level_zero library")
+ if(UNIX)
+    target_link_libraries(omptarget.rtl.level_zero PRIVATE
+        ${LIBOMPTARGET_DEP_LEVEL_ZERO_LIBRARY})
+  elseif(WIN32)
+    # Full path to the Level Zero library is recognized as a linker option, so we
+    # separate directory and file name
+    cmake_path(GET LIBOMPTARGET_DEP_LEVEL_ZERO_LIBRARY PARENT_PATH LEVEL_ZERO_LIBRARY_PATH)
+    target_link_libraries(omptarget.rtl.level_zero PRIVATE ${LEVEL_ZERO_LIBRARY_NAME}
+        ${LIBOMP_LIB_FILE})
+    target_link_directories(omptarget.rtl.level_zero PRIVATE ${LEVEL_ZERO_LIBRARY_PATH})
+  else()
+    message(FATAL_ERROR "Missing platform support")
+  endif()
+else()
+  message(STATUS "Building Level Zero NG plugin for dlopened level_zero")
+  if(WIN32)
+    cmake_path(REPLACE_EXTENSION LEVEL_ZERO_LIBRARY_NAME dll)
+  endif()
----------------
jhuber6 wrote:

Does the L0 library name change? Why can't we just do `#ifdef _WIN32` in the source.

https://github.com/llvm/llvm-project/pull/158900