cdf35f8782
The change adds a new reduction that recognizes the construction of a type environment from components
HTypeBind(HTypeEval(env, e1), HTypeEval(env, e2))
and replace with an equivalent expression that constructs the same derived type environment directly
HTypeEval(env, ...e1...e2...)
This change speeds up the benchmarks that iterate `Map.entries` by roughly 10-25%.
---
Type arguments are passed as separate values [1]. This means that the generative constructor factory `MapEntry<K,V>(this.key, this.value)` has four parameters - `MapEntry$(key, value, $K, $V)`. The passed arguments usually come from the same place, perhaps extracted from the type of the current object, `this.$ti._eval("1")` and `this.$ti._eval("2")`.
Inside `MapEntry$`, the type parameters are re-assembled into a type environment:
$K._eval("@<0>")._bind($V)
which is used to construct the object type
$K._eval("@<0>")._bind($V)._eval("MapEntry<1,2>")
After inlining:
$K = this.$ti._eval("1");
$V = this.$ti._eval("2");
$K._eval("@<0>")._bind($V)._eval("MapEntry<1,2>")
After GVN, and reducing the adjacent `._eval("1")._eval("@<0>")` to `._eval("@<1>")`:
t1 = this.$ti
t1._eval("@<1>")._bind(t1._eval("2"))._eval("MapEntry<1,2>")
The new reduction gives us:
this.$ti._eval("@<1,2>")._eval("MapEntry<1,2>")
which can be reduced further by combining adjacent HTypeEvals:
this.$ti._eval("MapEntry<1,2>")
[1]: It would be better to pass the type arguments as a single Rti object to avoid the extract-recombine pattern, but changing the calling convention is a more extensive change. In the meantime, this reduction cleans up the extract-recombine pattern when inlining brings the parts together.
Change-Id: I28801ce5d952d0f4e5ac1d55c252766159dcceef
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/367240
Reviewed-by: Mayank Patke <fishythefish@google.com>
Commit-Queue: Stephen Adams <sra@google.com>
|
||
|---|---|---|
| .dart_tool | ||
| .github | ||
| benchmarks | ||
| build | ||
| docs | ||
| pkg | ||
| runtime | ||
| samples | ||
| sdk | ||
| tests | ||
| third_party | ||
| tools | ||
| utils | ||
| .clang-format | ||
| .gitattributes | ||
| .gitconfig | ||
| .gitignore | ||
| .gn | ||
| .mailmap | ||
| .style.yapf | ||
| AUTHORS | ||
| BUILD.gn | ||
| CHANGELOG.md | ||
| codereview.settings | ||
| CONTRIBUTING.md | ||
| DEPS | ||
| LICENSE | ||
| OWNERS | ||
| PATENT_GRANT | ||
| PRESUBMIT.py | ||
| README.dart-sdk | ||
| README.md | ||
| sdk.code-workspace | ||
| sdk_args.gni | ||
| sdk_packages.yaml | ||
| SECURITY.md | ||
| WATCHLISTS | ||
Dart
An approachable, portable, and productive language for high-quality apps on any platform
Dart is:
-
Approachable: Develop with a strongly typed programming language that is consistent, concise, and offers modern language features like null safety and patterns.
-
Portable: Compile to ARM, x64, or RISC-V machine code for mobile, desktop, and backend. Compile to JavaScript or WebAssembly for the web.
-
Productive: Make changes iteratively: use hot reload to see the result instantly in your running app. Diagnose app issues using DevTools.
Dart's flexible compiler technology lets you run Dart code in different ways, depending on your target platform and goals:
-
Dart Native: For programs targeting devices (mobile, desktop, server, and more), Dart Native includes both a Dart VM with JIT (just-in-time) compilation and an AOT (ahead-of-time) compiler for producing machine code.
-
Dart Web: For programs targeting the web, Dart Web includes both a development time compiler (dartdevc) and a production time compiler (dart2js).
License & patents
Dart is free and open source.
See LICENSE and PATENT_GRANT.
Using Dart
Visit dart.dev to learn more about the language, tools, and to find codelabs.
Browse pub.dev for more packages and libraries contributed by the community and the Dart team.
Our API reference documentation is published at api.dart.dev, based on the stable release. (We also publish docs from our beta and dev channels, as well as from the primary development branch).
Building Dart
If you want to build Dart yourself, here is a guide to getting the source, preparing your machine to build the SDK, and building.
There are more documents in our repo at docs.
Contributing to Dart
The easiest way to contribute to Dart is to file issues.
You can also contribute patches, as described in Contributing.
Roadmap
Future plans for Dart are included in the combined Dart and Flutter roadmap on the Flutter wiki.