[SYCL] Simplified CMakeLists.txt file

Use a function to call common code in source/CMakeLists.txt and
plugins/opencl/CMakeLists.txt.
This change allows extension of other plugins to be easier and maintaining the
options at a single location.

Signed-off-by: Garima Gupta <garima.gupta@intel.com>

Author: garimagu

sycl/CMakeLists.txt

@@ -143,13 +143,40 @@ if (MSVC)
   list(APPEND SYCL_RT_LIBS sycld)
 endif()
 
+# This function allows building multiple libraries with the same options.
+# Currently used by sycl and plugins library. 
+function( add_libcxxsupport_gccworkaround LIB_NAME)
+  if (SYCL_USE_LIBCXX)
+      if ((CMAKE_CXX_COMPILER_ID STREQUAL "GNU") OR
+          (CMAKE_CXX_COMPILER_ID STREQUAL "Clang"))
+          target_compile_options(${LIB_NAME} PRIVATE -nostdinc++)
+          if ((NOT (DEFINED SYCL_LIBCXX_INCLUDE_PATH)) OR (NOT (DEFINED SYCL_LIBCXX_LIBRARY_PATH)))
+              message(FATAL_ERROR "When building with libc++ SYCL_LIBCXX_INCLUDE_PATHS and"
+                                  "SYCL_LIBCXX_LIBRARY_PATH should be set")
+          endif()
+          target_include_directories(${LIB_NAME} PRIVATE "${SYCL_LIBCXX_INCLUDE_PATH}")
+          target_link_libraries(${LIB_NAME} PRIVATE "-L${SYCL_LIBCXX_LIBRARY_PATH}" -nodefaultlibs -lc++ -lc++abi -lm -lc -lgcc_s -lgcc)
+      else()
+          message(FATAL_ERROR "Build with libc++ is not yet supported for this compiler")
+      endif()
+  else()
+
+# Workaround for bug in GCC version 5 and higher.
+# More information https://bugs.launchpad.net/ubuntu/+source/gcc-5/+bug/1568899
+    if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND
+        CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 5.0)
+    target_link_libraries(${LIB_NAME} PRIVATE gcc_s gcc)
+    endif()
+
+  endif()
+endfunction(add_libcxxsupport_gccworkaround)	
+
 # SYCL runtime library
-add_subdirectory(source)
+add_subdirectory( source )
 
 # SYCL toolchain builds all components: compiler, libraries, headers, etc.
 add_custom_target( sycl-toolchain
   DEPENDS ${SYCL_RT_LIBS}
-          pi_opencl
           clang
           clang-offload-wrapper
           clang-offload-bundler
@@ -173,7 +200,10 @@ option(SYCL_INCLUDE_TESTS
   "Generate build targets for the SYCL unit tests."
   ${LLVM_INCLUDE_TESTS})
 
+
+# Plugin Library
 add_subdirectory( plugins )
+
 add_subdirectory(tools)
 
 if(SYCL_INCLUDE_TESTS)

sycl/plugins/opencl/CMakeLists.txt

@@ -19,7 +19,7 @@ add_dependencies(pi_opencl
   ocl-headers
 )
 
-add_dependencies(sycl pi_opencl)
+add_dependencies(sycl-toolchain pi_opencl)
 
 set_target_properties(pi_opencl PROPERTIES LINKER_LANGUAGE CXX)
 
@@ -32,29 +32,7 @@ target_link_libraries( pi_opencl
     PRIVATE ${OpenCL_LIBRARIES}
 )
 
-if (SYCL_USE_LIBCXX)
-    if ((CMAKE_CXX_COMPILER_ID STREQUAL "GNU") OR
-        (CMAKE_CXX_COMPILER_ID STREQUAL "Clang"))
-        target_compile_options(pi_opencl PRIVATE -nostdinc++)
-        if ((NOT (DEFINED SYCL_LIBCXX_INCLUDE_PATH)) OR (NOT (DEFINED SYCL_LIBCXX_LIBRARY_PATH)))
-            message(FATAL_ERROR "When building with libc++ SYCL_LIBCXX_INCLUDE_PATHS and"
-                                "SYCL_LIBCXX_LIBRARY_PATH should be set")
-        endif()
-        target_include_directories(pi_opencl PRIVATE "${SYCL_LIBCXX_INCLUDE_PATH}")
-        target_link_libraries(pi_opencl PRIVATE "-L${SYCL_LIBCXX_LIBRARY_PATH}" -nodefaultlibs -lc++ -lc)
-    else()
-        message(FATAL_ERROR "Build with libc++ is not yet supported for this compiler")
-    endif()
-else()
-
-# Workaround for bug in GCC version 5 and higher.
-# More information https://bugs.launchpad.net/ubuntu/+source/gcc-5/+bug/1568899
-if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND
-    CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 5.0)
-  target_link_libraries(pi_opencl PRIVATE gcc_s gcc)
-endif()
-
-endif()
+add_libcxxsupport_gccworkaround(pi_opencl)
 
 install(TARGETS pi_opencl
     LIBRARY DESTINATION "lib" COMPONENT pi_opencl

sycl/source/CMakeLists.txt

@@ -26,29 +26,9 @@ function(add_sycl_rt_library LIB_NAME)
       PRIVATE ${OpenCL_LIBRARIES}
       PRIVATE ${CMAKE_DL_LIBS}
   )
-  if (SYCL_USE_LIBCXX)
-      if ((CMAKE_CXX_COMPILER_ID STREQUAL "GNU") OR
-          (CMAKE_CXX_COMPILER_ID STREQUAL "Clang"))
-          target_compile_options(${LIB_NAME} PRIVATE -nostdinc++)
-          if ((NOT (DEFINED SYCL_LIBCXX_INCLUDE_PATH)) OR (NOT (DEFINED SYCL_LIBCXX_LIBRARY_PATH)))
-              message(FATAL_ERROR "When building with libc++ SYCL_LIBCXX_INCLUDE_PATHS and"
-                                  "SYCL_LIBCXX_LIBRARY_PATH should be set")
-          endif()
-          target_include_directories(${LIB_NAME} PRIVATE "${SYCL_LIBCXX_INCLUDE_PATH}")
-          target_link_libraries(${LIB_NAME} PRIVATE "-L${SYCL_LIBCXX_LIBRARY_PATH}" -nodefaultlibs -lc++ -lc++abi -lm -lc -lgcc_s -lgcc)
-      else()
-          message(FATAL_ERROR "Build with libc++ is not yet supported for this compiler")
-      endif()
-  else()
 
-# Workaround for bug in GCC version 5 and higher.
-# More information https://bugs.launchpad.net/ubuntu/+source/gcc-5/+bug/1568899
-    if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND
-        CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 5.0)
-    target_link_libraries(${LIB_NAME} PRIVATE gcc_s gcc)
-    endif()
+  add_libcxxsupport_gccworkaround(${LIB_NAME})
 
-  endif()
 endfunction(add_sycl_rt_library)
 
 set(SYCL_SOURCES