move OPTIMIZE_SIZE

Author: jathu

CMakeLists.txt

@@ -120,8 +120,7 @@ if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
   set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -s")
 endif()
 
-option(OPTIMIZE_SIZE "Build executorch runtime optimizing for binary size" OFF)
-if(OPTIMIZE_SIZE)
+if(EXECUTORCH_OPTIMIZE_SIZE)
   # -Os: Optimize for size.
   set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -Os")
 else()

docs/source/using-executorch-building-from-source.md

@@ -164,7 +164,7 @@ The release build offers optimizations intended to improve performance and reduc
 To further optimize the release build for size, use both:
 ```bash
 -DCMAKE_BUILD_TYPE=Release \
--DOPTIMIZE_SIZE=ON
+-DEXECUTORCH_OPTIMIZE_SIZE=ON
 ```
 
 See [CMakeLists.txt](https://github.com/pytorch/executorch/blob/main/CMakeLists.txt)

test/build_optimized_size_test.sh

@@ -27,7 +27,7 @@ cmake_install_executorch_lib() {
           -DCMAKE_BUILD_TYPE=MinSizeRel \
           -DEXECUTORCH_BUILD_EXECUTOR_RUNNER=OFF \
           -DEXECUTORCH_BUILD_KERNELS_OPTIMIZED=ON \
-          -DOPTIMIZE_SIZE=ON \
+          -DEXECUTORCH_OPTIMIZE_SIZE=ON \
           -DPYTHON_EXECUTABLE="$PYTHON_EXECUTABLE" \
           -Bcmake-out .
   cmake --build cmake-out -j9 --target install --config MinSizeRel

test/build_size_test.sh

@@ -28,7 +28,7 @@ cmake_install_executorch_lib() {
           -DCMAKE_INSTALL_PREFIX=cmake-out \
           -DCMAKE_BUILD_TYPE=Release \
           -DEXECUTORCH_BUILD_EXECUTOR_RUNNER=OFF \
-          -DOPTIMIZE_SIZE=ON \
+          -DEXECUTORCH_OPTIMIZE_SIZE=ON \
           -DPYTHON_EXECUTABLE="$PYTHON_EXECUTABLE" \
           ${EXTRA_BUILD_ARGS} \
           -Bcmake-out .

tools/cmake/preset/default.cmake

@@ -54,6 +54,11 @@ define_overridable_option(
   "Build with ET_EVENT_TRACER_ENABLED"
   BOOL OFF
 )
+define_overridable_option(
+  EXECUTORCH_OPTIMIZE_SIZE
+  "Build executorch runtime optimizing for binary size"
+  BOOL OFF
+)
 
 # MARK: - Validations
 # At this point all the options should be configured with their final value.