Add NGRAPH_UNIT_TEST_ENABLE cmake key to control backends build in un…

…it-test target (#6232)

ngraph/CMakeLists.txt

@@ -84,6 +84,7 @@ if (APPLE)
 endif()
 
 option(NGRAPH_UNIT_TEST_ENABLE "Control the building of unit tests" ON)
+option(NGRAPH_UNIT_TEST_BACKENDS_ENABLE "Control the building of unit tests using backends" ON)
 option(NGRAPH_INTERPRETER_ENABLE "Control the building of the INTERPRETER backend" ON)
 option(NGRAPH_DEBUG_ENABLE "Enable output for NGRAPH_DEBUG statements" OFF)
 option(NGRAPH_ONNX_IMPORT_ENABLE "Enable ONNX importer" OFF)
@@ -117,6 +118,7 @@ message(STATUS "NGRAPH_THREAD_SANITIZER_ENABLE:       ${NGRAPH_THREAD_SANITIZER_
 message(STATUS "NGRAPH_UB_SANITIZER_ENABLE:           ${NGRAPH_UB_SANITIZER_ENABLE}")
 message(STATUS "NGRAPH_USE_PROTOBUF_LITE:             ${NGRAPH_USE_PROTOBUF_LITE}")
 message(STATUS "NGRAPH_UNIT_TEST_ENABLE:              ${NGRAPH_UNIT_TEST_ENABLE}")
+message(STATUS "NGRAPH_UNIT_TEST_BACKENDS_ENABLE:     ${NGRAPH_UNIT_TEST_BACKENDS_ENABLE}")
 
 # Setup CMAKE_ARGS to be forwarded to External Projects
 set(NGRAPH_FORWARD_CMAKE_ARGS

ngraph/test/CMakeLists.txt

@@ -304,7 +304,7 @@ set(SRC
 set_source_files_properties(includes.cpp PROPERTIES COMPILE_DEFINITIONS
     NGRAPH_INCLUDES="${PROJECT_SOURCE_DIR}/src/ngraph")
 
-if (ENABLE_MKL_DNN)
+if (ENABLE_MKL_DNN AND NGRAPH_UNIT_TEST_BACKENDS_ENABLE)
     message(STATUS "NGRAPH_TESTS: IE:CPU enabled")
     set(ACTIVE_BACKEND_LIST ${ACTIVE_BACKEND_LIST} "IE:CPU")
     if (ENABLE_STRICT_DEPENDENCIES)
@@ -314,7 +314,7 @@ if (ENABLE_MKL_DNN)
     endif()
 endif()
 
-if (ENABLE_CLDNN)
+if (ENABLE_CLDNN AND NGRAPH_UNIT_TEST_BACKENDS_ENABLE)
     message(STATUS "NGRAPH_TESTS: IE:GPU enabled")
     set(ACTIVE_BACKEND_LIST ${ACTIVE_BACKEND_LIST} "IE:GPU")
     if (ENABLE_STRICT_DEPENDENCIES)
@@ -324,7 +324,7 @@ if (ENABLE_CLDNN)
     endif()
 endif()
 
-if (NGRAPH_INTERPRETER_ENABLE)
+if (NGRAPH_INTERPRETER_ENABLE AND NGRAPH_UNIT_TEST_BACKENDS_ENABLE)
     list(APPEND SRC
         builder.cpp
         backend_api.cpp)