Revert "[tools] Allow precompiling gen_kernel and compile_platform" This reverts commit 5cda2a871cf274a1943e56e208634055ea996598. Reason for revert: broke Flutter build. Original change's description: > [tools] Allow precompiling gen_kernel and compile_platform > > When iterating on core library changes or changes in the AOT compiler > many seconds are wasted waiting on gen_kernel/compile_platform to > parse Dart code. This happens because we are running these tools > from sources on prebuilt Dart SDK. > > This CL allows SDK developer to opt-in into AOT compiling these > tools by adding `precompile_tools=true` to their DART_GN_ARGS. > > AOT compilation is performed using prebuilt SDK - so these > executables do not need to be recompiled if core libraries or > VM changes reducing iteration cycles. > > pkg/vm/tool/precompiler2 is tweaked to detect when DART_GN_ARGS > contains `precompile_tools=true` and use precompiled > gen_kernel.exe instead of running it from source. > > Using precompiled compile_platform takes vm_platform_strong.dill > build from 20 seconds to 3 seconds. > > Using precompiled gen_kernel takes small benchmark build from > ~10 seconds to 2 seconds. > > TEST=manually tested > > Change-Id: Ieec6ad4e1081023d140eb744f0a3cd0c754414ca > Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/367940 > Commit-Queue: Slava Egorov <vegorov@google.com> > Reviewed-by: Martin Kustermann <kustermann@google.com> Change-Id: Id3e4eb44d33516f31c165d9a1e55911e8d356e7f No-Presubmit: true No-Tree-Checks: true No-Try: true Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/367960 Commit-Queue: Slava Egorov <vegorov@google.com> Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com> Reviewed-by: Alexander Markov <alexmarkov@google.com> https://dart.googlesource.com/sdk/+/a17d709a1dcc4beaba1dfc32c8bb98227c28263a
Monorepo is:
With depot_tools installed and on your path, create a directory for your monorepo checkout and run these commands to create a gclient solution in that directory:
mkdir monorepo cd monorepo gclient config --unmanaged https://dart.googlesource.com/monorepo gclient sync -D
This gives you a checkout in the monorepo directory that contains:
monorepo/ DEPS - the DEPS used for this gclient checkout commits.json - the pinned commits for Dart, flutter/engine, and flutter/flutter tools/ - scripts used to create monorepo DEPS engine/src/ - the flutter/buildroot repo flutter/ - the flutter/engine repo out/ - the build directory, where Flutter engine builds are created third_party/ - Flutter dependencies checked out by DEPS dart/ - the Dart SDK checkout. third_party - Dart dependencies, also used by Flutter flutter/ - the flutter/flutter repo
Flutter's instructions for building the engine are at Compiling the engine
They can be followed closely, with a few changes:
goma_ctl ensure_start is sufficient.Example build commands that work on linux:
MONOREPO_PATH=$PWD if [[ ! $PATH =~ (^|:)$MONOREPO_PATH/flutter/bin(:|$) ]]; then PATH=$MONOREPO_PATH/flutter/bin:$PATH fi export GOMA_DIR=$(dirname $(command -v gclient))/.cipd_bin goma_ctl ensure_start pushd engine/src flutter/tools/gn --goma --no-prebuilt-dart-sdk --unoptimized --full-dart-sdk autoninja -C out/host_debug_unopt popd
The Flutter commands used to build and run apps will use the locally built Flutter engine and Dart SDK, instead of the one downloaded by the Flutter tool, if the --local-engine option is provided.
For example, to build and run the Flutter spinning square sample on the web platform,
MONOREPO_PATH=$PWD cd flutter/examples/layers flutter --local-engine=host_debug_unopt \ -d chrome run widgets/spinning_square.dart cd $MONOREPO_PATH
To build for desktop, specify the desktop platform device in flutter run as -d macos or -d linux or -d windows. You may also need to run the command
flutter create --platforms=windows,macos,linux
on existing apps, such as sample apps. New apps created with flutter create already include these support files. Details of desktop support are at Desktop Support for Flutter
Tests in the Flutter source tree can be run with the flutter test command, run in the directory of a package containing tests. For example:
MONOREPO_PATH=$PWD cd flutter/packages/flutter flutter test --local-engine=host_debug_unopt cd $MONOREPO_PATH
Please file an issue or email the dart-engprod team with any problems with or questions about using monorepo.
We will update this documentation to address them.
flutter commands may download the engine and Dart SDK files for the configured channel, even though they will be using the local engine and its SDK.gclient sync needs to be run in an administrator session, because some installed dependencies create symlinks.