Allow options to be set by presets (#10767)

### Summary

In this diff we create a helper that will allow presets to set options.
Again this is mostly a helper to check if the option has been defined
already, then no-oping.

To test it, I also create the first preset `macos-arm64`. I will test it
in upcoming diffs.

### Test plan

pytest for now, manual test in future diffs


cc @larryliu0820

Author: jathu

CMakeLists.txt

@@ -178,8 +178,6 @@ option(EXECUTORCH_BUILD_ARM_BAREMETAL
        "Build the Arm Baremetal flow for Cortex-M and Ethos-U" OFF
 )
 
-option(EXECUTORCH_BUILD_COREML "Build the Core ML backend" OFF)
-
 option(EXECUTORCH_BUILD_KERNELS_CUSTOM "Build the custom kernels" OFF)
 
 option(EXECUTORCH_BUILD_KERNELS_CUSTOM_AOT "Build the custom ops lib for AOT"

tools/cmake/Utils.cmake

@@ -45,10 +45,6 @@ function(executorch_print_configuration_summary)
   message(STATUS "  EXECUTORCH_BUILD_CADENCE               : "
                  "${EXECUTORCH_BUILD_CADENCE}"
   )
-  message(
-    STATUS
-      "  EXECUTORCH_BUILD_COREML                : ${EXECUTORCH_BUILD_COREML}"
-  )
   message(
     STATUS
       "  EXECUTORCH_BUILD_CPUINFO               : ${EXECUTORCH_BUILD_CPUINFO}"

tools/cmake/common/preset.cmake

@@ -26,6 +26,7 @@ function(announce_configured_options NAME)
   endif()
 endfunction()
 
+
 # Print the configured options.
 function(print_configured_options)
   get_property(_options GLOBAL PROPERTY _announce_configured_options)
@@ -52,13 +53,15 @@ function(print_configured_options)
   message(STATUS "---------------------------")
 endfunction()
 
+
 # Enforce option names to always start with EXECUTORCH.
 function(enforce_executorch_option_name NAME)
   if(NOT "${NAME}" MATCHES "^EXECUTORCH_")
     message(FATAL_ERROR "Option name '${NAME}' must start with EXECUTORCH_")
   endif()
 endfunction()
 
+
 # Define an overridable option.
 #   1) If the option is already defined in the process, then store that in cache
 #   2) If the option is NOT set, then store the default value in cache
@@ -77,3 +80,14 @@ macro(define_overridable_option NAME DESCRIPTION VALUE_TYPE DEFAULT_VALUE)
 
   announce_configured_options(${NAME})
 endmacro()
+
+
+# Set an overridable option.
+macro(set_overridable_option NAME VALUE)
+  # If the user has explitily set the option, do not override it.
+  if(DEFINED ${NAME})
+    return()
+  endif()
+
+  set(${NAME} ${VALUE} CACHE STRING "")
+endmacro()

tools/cmake/common/preset_test.py

@@ -223,3 +223,70 @@ def test_define_overridable_option_cli_override_with_set_override(self):
         self.run_cmake(cmake_args=["-DEXECUTORCH_TEST_MESSAGE='cli value'"])
         # If an option is set through cmake, it should NOT be overridable from the CLI.
         self.assert_cmake_cache("EXECUTORCH_TEST_MESSAGE", "set value", "STRING")
+
+    def test_set_overridable_option_before(self):
+        _cmake_lists_txt = """
+            cmake_minimum_required(VERSION 3.24)
+            project(test_preset)
+            include(${PROJECT_SOURCE_DIR}/preset.cmake)
+            set_overridable_option(EXECUTORCH_TEST_MESSAGE "from set_overridable_option")
+            add_subdirectory(build)
+        """
+        _build_cmake_lists_txt = """
+            define_overridable_option(EXECUTORCH_TEST_MESSAGE "test message" STRING "move fast")
+        """
+        self.create_workspace(
+            {
+                "CMakeLists.txt": _cmake_lists_txt,
+                "build": {
+                    "CMakeLists.txt": _build_cmake_lists_txt,
+                },
+            }
+        )
+        self.run_cmake()
+        self.assert_cmake_cache(
+            "EXECUTORCH_TEST_MESSAGE", "from set_overridable_option", "STRING"
+        )
+
+    def test_set_overridable_option_after(self):
+        _cmake_lists_txt = """
+            cmake_minimum_required(VERSION 3.24)
+            project(test_preset)
+            include(${PROJECT_SOURCE_DIR}/preset.cmake)
+            add_subdirectory(build)
+            set_overridable_option(EXECUTORCH_TEST_MESSAGE "from set_overridable_option")
+        """
+        _build_cmake_lists_txt = """
+            define_overridable_option(EXECUTORCH_TEST_MESSAGE "test message" STRING "move fast")
+        """
+        self.create_workspace(
+            {
+                "CMakeLists.txt": _cmake_lists_txt,
+                "build": {
+                    "CMakeLists.txt": _build_cmake_lists_txt,
+                },
+            }
+        )
+        self.run_cmake()
+        self.assert_cmake_cache("EXECUTORCH_TEST_MESSAGE", "move fast", "STRING")
+
+    def test_set_overridable_option_with_cli_override(self):
+        _cmake_lists_txt = """
+            cmake_minimum_required(VERSION 3.24)
+            project(test_preset)
+            include(${PROJECT_SOURCE_DIR}/preset.cmake)
+            add_subdirectory(build)
+        """
+        _build_cmake_lists_txt = """
+            define_overridable_option(EXECUTORCH_TEST_MESSAGE "test message" STRING "move fast")
+        """
+        self.create_workspace(
+            {
+                "CMakeLists.txt": _cmake_lists_txt,
+                "build": {
+                    "CMakeLists.txt": _build_cmake_lists_txt,
+                },
+            }
+        )
+        self.run_cmake(cmake_args=["-DEXECUTORCH_TEST_MESSAGE='from the cli'"])
+        self.assert_cmake_cache("EXECUTORCH_TEST_MESSAGE", "from the cli", "STRING")

tools/cmake/preset/default.cmake

@@ -15,3 +15,4 @@ endif()
 # MARK: - Definitions
 
 define_overridable_option(EXECUTORCH_ENABLE_LOGGING "Build with ET_LOG_ENABLED" BOOL ${_is_build_type_debug})
+define_overridable_option(EXECUTORCH_BUILD_COREML "Build the Core ML backend" BOOL OFF)

tools/cmake/preset/macos-arm64.cmake

@@ -0,0 +1,7 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+set_overridable_option(EXECUTORCH_BUILD_COREML ON)