| commit | dad75c5eeffe51b8e93d650c202df126a8dec55c | [log] [tgz] |
|---|---|---|
| author | Nate Biggs <natebiggs@google.com> | Wed Aug 07 17:27:38 2024 +0000 |
| committer | dart-internal-monorepo <dart-internal-monorepo@dart-ci-internal.iam.gserviceaccount.com> | Wed Aug 07 10:29:26 2024 -0700 |
| tree | 1e522b63f30d5acf70fb66d74295189868f27bbc | |
| parent | df0c04af0ff6f9d0a1ce954d3bbcbea2d4ebbb08 [diff] |
[dart2wasm] Modify wasm_builder to support multi-module deferred loading (2/2). Golem results verifying no regressions from this change: https://golem.corp.goog/Revision?repository=dart&revision=111273&patch=19368 This modifies the wasm_builder to emit types in minimally sized recursive groups. The main motivation of these changes is to minimize the size of the type section when dart2wasm produces multiple modules. If we included every type in every module, for small modules the type section would be a very significant % of the total file size (in a small example it was ~98% for a deferred module). The two main changes are: 1) Type tree-shaking for each module. We detect which types are actually used in that module (via instructions, function signatures, etc.) and only include the detected types in the module's type section. This simplifies the compilation pipeline as we don't need to worry about assigning types to modules, we can just build the module as before and post-process the IR to collect the set of used types. 2) Create minimally-sized recursive groups. In order for wasm type-checking to work across modules, equal types have to be in equal recursive groups. Tree-shaking therefore has to occur at the rec group level as opposed to the individual type level. So to make tree-shaking effective, we need the smallest possible rec groups. We achieve this by creating a graph of the wasm types' dependencies and then calculating the set of strongly connected components for that graph. Each component represents a minimally-sized recursive group. The DAG formed by the components is the order to emit them so that definitions come before usages. Importantly, by separating types into different rec groups, we are also changing the equivalence relationship between them. This can have a meaningful impact on binaryen's ability to optimize the module, two types that were distinguishable might not be anymore. To avoid this regression we group together any types that are structurally equivalent. This way binaryen will differentiate them as separate types as they were in the original Dart source. Change-Id: I67acdd21a89ff2718e8bbd6360f342c150494a9a Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/378764 Reviewed-by: Ömer Ağacan <omersa@google.com> Reviewed-by: Martin Kustermann <kustermann@google.com> Commit-Queue: Nate Biggs <natebiggs@google.com> https://dart.googlesource.com/sdk/+/d9b5eec82956b90481f763ad0989e6bd00361024
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.