Handle to DirectHandle migration tool

A clang tool for the migration of v8::internal::Handle<T> to v8::internal::DirectHandle<T>. This is only useful for the V8 code base, as such handles can only be used there. The two types are only different in builds with v8_enable_direct_handle=true, which implies v8_enable_conservative_stack_scanning=true, so the tool should be applied to such a debug build.

Building

The first time, build with:

tools/clang/scripts/build.py --without-android --without-fuchsia --extra-tools v8_handle_migrate

Then, recompile with:

ninja -C third_party/llvm-build/Release+Asserts v8_handle_migrate

Usage

Build the release with which to use it (see above for GN args), e.g.:

autoninja -C out/css all

You may need to generate the database of compile commands:

tools/clang/scripts/generate_compdb.py -p out/css -o out/css/compile_commands.json

Then, process files with:

tools/clang/scripts/run_tool.py --tool v8_handle_migrate -p out/css files.cpp

Testing

Run the tests with:

tools/clang/scripts/test_tool.py v8_handle_migrate --apply-edits

Notice that the tests use mock versions of the relevant V8 header files.