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dart / sdk / 1aa7a9397a0f3c3d1502ba81e172994a99173446
commit1aa7a9397a0f3c3d1502ba81e172994a99173446[log] [tgz]
authorDaco Harkes <dacoharkes@google.com>Fri Feb 03 12:55:31 2023 +0000
committerCommit Queue <dart-scoped@luci-project-accounts.iam.gserviceaccount.com>Fri Feb 03 12:55:31 2023 +0000
tree4866f242190cbb4199d103c327b981efb8ae3090
parentbf7d643686ba4101b5f549bde3a266d8beff910c [diff]
[vm] `MemoryCopyInstr` optimize constant src and dest start

When constants are passed in to the source and destination start,
no registers are needed for these. The constants are directly compiled
into the machine code. If the constant happens to be 0, no machine
code is emitted at all.

I did not measure any speed improvements. Likely the micro-code
schedulers in the CPUs already noticed the no-ops.

I have verified manually that we emit smaller machine code with
these changes on x64.

TEST=runtime/vm/compiler/backend/memory_copy_test.cc

Bug: https://github.com/dart-lang/sdk/issues/51031

Change-Id: I70f12c9ae299b44a8f5007ca3a8c5ee56a9aff40
Cq-Include-Trybots: luci.dart.try:vm-precomp-ffi-qemu-linux-release-riscv64-try,vm-precomp-ffi-qemu-linux-release-arm-try,vm-ffi-android-debug-arm64c-try,vm-ffi-android-debug-arm-try,vm-kernel-nnbd-mac-debug-arm64-try,vm-kernel-nnbd-win-debug-x64-try,vm-kernel-win-debug-x64c-try,vm-kernel-win-debug-ia32-try,vm-kernel-nnbd-linux-debug-ia32-try,vm-reload-rollback-linux-debug-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/279170
Reviewed-by: Alexander Markov <alexmarkov@google.com>
6 files changed
tree: 4866f242190cbb4199d103c327b981efb8ae3090
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .style.yapf
  21. .vpython
  22. AUTHORS
  23. BUILD.gn
  24. CHANGELOG.md
  25. codereview.settings
  26. CONTRIBUTING.md
  27. DEPS
  28. LICENSE
  29. OWNERS
  30. PATENT_GRANT
  31. PRESUBMIT.py
  32. README.dart-sdk
  33. README.md
  34. sdk_args.gni
  35. SECURITY.md
  36. WATCHLISTS
README.md

Dart

A client-optimized language for fast apps on any platform

Dart is:

  • Optimized for UI: Develop with a programming language specialized around the needs of user interface creation.

  • Productive: Make changes iteratively: use hot reload to see the result instantly in your running app.

  • Fast on all platforms: Compile to ARM & x64 machine code for mobile, desktop, and backend. Or compile to JavaScript for the web.

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).

Dart platforms illustration

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 on our wiki.

Contributing to Dart

The easiest way to contribute to Dart is to file issues.

You can also contribute patches, as described in Contributing.