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Tess Strickland 06d7a2352e [vm/compiler] Change MemoryCopy to also take untagged addresses.
This CL adds the ability to pass the payload address of the source
and destination directly to the MemoryCopy instruction as an untagged
value.

The new translation of the _TypedListBase._memMoveN methods use the new
MemoryCopy constructor, retrieving the untagged value of the data field
of both the source and destination. This way, if inlining exposes the
allocation of the object from which the data field is being retrieved,
then allocation sinking can remove the intermediate allocation if there
are no escaping uses of the object.

Since Pointer.asTypedList allocates such ExternalTypedData objects,
this CL makes that method inlined if at all possible, which removes
the intermediate allocation if the only use of the TypedData object
is to call setRange for memory copying purposes.

This CL also separates unboxed native slots into two groups: those
that contain untagged addresses and those that do not. The former
group now have the kUntagged representation, which mimics the old
use of LoadUntagged for the PointerBase data field and also ensures
that any arithmetic operations on untagged addresses must first be
explicitly converted to an unboxed integer and then explicitly converted
back to untagged before being stored in a slot that contains untagged
addresses.

When a unboxed native slot that contains untagged addresses is defined,
the definition also includes a boolean which represents whether
addresses that may be moved by the GC can be stored in this slot or not.
The redundancy eliminator uses this to decide whether it is safe to
eliminate a duplicate load, replace a load with the value originally
stored in the slot, or lift a load out of a loop.

In particular, the PointerBase data field may contain GC-moveable
addresses, but only for internal TypedData objects and views, not
for external TypedData objects or Pointers. To allow load optimizations
involving the latter, the LoadField and StoreField instructions now
take boolean flags for whether loads or stores from the slot are
guaranteed to not be GC-moveable, to override the information from
the slot argument.

Notable benchmark changes on x64 (similar for other archs unless noted):

JIT:
* FfiMemory.PointerPointer: 250.7%
* FfiStructCopy.Copy1Bytes: -26.73% (only x64)
* FfiStructCopy.Copy32Bytes: -25.18% (only x64)
* MemoryCopy.64.setRange.Pointer.Uint8: 19.36%
* MemoryCopy.64.setRange.Pointer.Double: 18.96%
* MemoryCopy.8.setRange.Pointer.Double: 17.59%
* MemoryCopy.8.setRange.Pointer.Uint8: 19.46%

AOT:
* FfiMemory.PointerPointer: 323.5%
* FfiStruct.FieldLoadStore: 483.3%
* FileIO_readwrite_64kb: 15.39%
* FileIO_readwrite_512kb (Intel Xeon): 46.22%
* MemoryCopy.512.setRange.Pointer.Uint8: 35.20%
* MemoryCopy.64.setRange.Pointer.Uint8: 55.40%
* MemoryCopy.512.setRange.Pointer.Double: 29.45%
* MemoryCopy.64.setRange.Pointer.Double: 60.37%
* MemoryCopy.8.setRange.Pointer.Double: 59.54%
* MemoryCopy.8.setRange.Pointer.Uint8: 55.40%
* FfiStructCopy.Copy32Bytes: 398.3%
* FfiStructCopy.Copy1Bytes: 1233%

TEST=vm/dart/address_local_pointer, vm/dart/pointer_as_typed_list

Issue: https://github.com/dart-lang/sdk/issues/42072
Fixes: https://github.com/dart-lang/sdk/issues/53124

Cq-Include-Trybots: luci.dart.try:vm-ffi-qemu-linux-release-arm-try,vm-eager-optimization-linux-release-x64-try,vm-linux-release-x64-try,vm-linux-debug-x64-try,vm-aot-linux-release-x64-try,vm-aot-linux-debug-x64-try
Change-Id: I563e0bfac5b1ac6cf1111649934067c12891b631
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/324820
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
2023-10-13 19:06:30 +00:00
.dart_tool [infra] re-land work to auto-generate .dart_tool/package_config.json 2022-04-12 17:21:02 +00:00
.github Bump ossf/scorecard-action from 2.2.0 to 2.3.0 2023-10-12 07:49:19 +00:00
benchmarks [benchmark] Add benchmark prefix to UiMatrix benchmark. 2023-09-18 22:41:23 +00:00
build [Fuchsia] Allows FuchsiaEmulatorCFv2 to start daemon and emulator 2023-10-03 22:56:39 +00:00
docs Spelling pkg analyzer lib 2023-01-25 14:08:27 +00:00
pkg [vm/compiler] Change MemoryCopy to also take untagged addresses. 2023-10-13 19:06:30 +00:00
runtime [vm/compiler] Change MemoryCopy to also take untagged addresses. 2023-10-13 19:06:30 +00:00
samples Fix samples/ffi/http/test/http_test.dart 2023-09-29 20:58:07 +00:00
sdk [vm/compiler] Change MemoryCopy to also take untagged addresses. 2023-10-13 19:06:30 +00:00
tests [doc/io] Add documentation for HttpSession 2023-10-13 17:59:08 +00:00
third_party [dart2wasm] Switch to final GC encodings & Roll Chrome 119 + D8 2023-10-13 17:09:19 +00:00
tools Reland "Bump version to 3.3." 2023-10-06 19:00:58 +00:00
utils [Reland] [dartdev] Convert gen_kernel.dart.snapshot into an AOT snapshot 2023-09-26 21:46:58 +00:00
.clang-format
.gitattributes [web] rename suite dart2js -> web. 2021-02-04 23:11:32 +00:00
.gitconfig [infra] Add documentation to .gitconfig 2018-06-11 18:24:16 +00:00
.gitignore [tool] Bisection tool 2023-07-13 13:22:26 +00:00
.gn [Fuchsia] Import test scripts from chromium and use it to download image 2023-08-22 19:59:25 +00:00
.mailmap Fixed various typos in a lot of files 2022-07-25 12:21:59 +00:00
.style.yapf Mass format python with yapf 2019-08-05 20:34:31 +00:00
.vpython [infra] Add .vpython spec to fix gsutil on the bots (#31065) 2018-10-11 15:11:35 +00:00
AUTHORS Simplify the license situation 2022-09-14 21:06:22 +00:00
BUILD.gn [ffi] Reland the iNativeCallable.listener example test. 2023-09-28 22:41:42 +00:00
CHANGELOG.md [dartdev] Mention new cli template for dart create in changelog 2023-10-11 14:52:34 +00:00
codereview.settings [infra] Default presubmits to use python3 2021-08-24 08:20:47 +00:00
CONTRIBUTING.md Update CONTRIBUTING.md 2023-05-16 13:04:13 +00:00
DEPS [dart2wasm] Switch to final GC encodings & Roll Chrome 119 + D8 2023-10-13 17:09:19 +00:00
LICENSE Update LICENSE 2021-04-08 07:57:10 +00:00
OWNERS [owners] update the top-level owners file 2022-11-11 21:03:52 +00:00
PATENT_GRANT Rename patent file 2019-08-16 12:03:17 +00:00
PRESUBMIT.py [presubmit] Remove check to keep _2 suites in sync 2023-07-21 16:08:49 +00:00
README.dart-sdk Fix README.dart-sdk file to reflect current contents of the SDK 2023-02-02 03:10:09 +00:00
README.md master => main 2021-09-10 08:02:49 +00:00
sdk.code-workspace Add an explicit Visual Studio Code workspace 2023-05-17 23:08:19 +00:00
sdk_args.gni Fix typos 2022-06-15 11:08:28 +00:00
SECURITY.md Add link to published advisories 2022-02-08 19:45:07 +00:00
WATCHLISTS Add a watchlist entry for changes to _fe_analyzer_shared 2023-03-31 13:59:27 +00:00

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.