Here's how the deadlock can happen:
* The vm-service background compiler asks all threads to go to a
safepoint before it finalizes the code. Then it finalizes the
code and notifies code observers. A code observer posts a
message to the vm-service. Posting this message requires holding the
monitor of the receiving isolate's message handler (see
MessageHandler::PostMessage).
* The vm-service mutator holds it's message handlers monitor and
enters the isolate (see MessageHandler::HandleMessages). The
StartIsolateScope schedules the mutator thread, which will in return
see that BG compiler wants to safepoint, so it waits for BG compiler
to finish.
At this point the mutator holds the MessageHandler's monitor and waits
for BG compiler to finish safepoint. The BG compiler tries to post a
message to the message handler (and the monitor is locked).
-> This CL ensures the BG compiler only arranges a safepoint before it
starts creating the instructions object. It fills it in and exits the
safepoint again. Only then do we notify code observers.
Furthermore this CL ensures we transition out of VM to native state
before calling the Dart_PostCMessage() function.
Change-Id: I5320440d54ca303a1ccc7556600a42d37cd6e1de
Reviewed-on: https://dart-review.googlesource.com/c/93421
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
This is the next step towards preventing compiler from directly peeking
into runtime and instead interact with runtime through a well defined
surface. The goal of the refactoring to locate all places where compiler
accesses some runtime information and partion those accesses into two
categories:
- creating objects in the host runtime (e.g. allocating strings, numbers, etc)
during compilation;
- accessing properties of the target runtime (e.g. offsets of fields) to
embed those into the generated code;
This change introduces dart::compiler and dart::compiler::target namespaces.
All code in the compiler will gradually be moved into dart::compiler namespace.
One of the motivations for this change is to be able to prevent access to
globally defined host constants like kWordSize by shadowing them in the
dart::compiler namespace.
The nested namespace dart::compiler::target hosts all information about
target runtime that compiler could access, e.g. compiler::target::kWordSize
defines word size of the target which will eventually be made different
from the host kWordSize (defined by dart::kWordSize).
The API for compiler to runtime interaction is placed into compiler_api.h.
Note that we still permit runtime to access compiler internals directly -
this is not going to be decoupled as part of this work.
Issue https://github.com/dart-lang/sdk/issues/31709
Change-Id: If4396d295879391becfa6c38d4802bbff81f5b20
Reviewed-on: https://dart-review.googlesource.com/c/90242
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Test Plan:
Will be tested by following revisions which introduce optimizations that invoke the
new entrypoint.
Change-Id: I56d714bceb92c44a13c46d52457154b82577aa8c
Cq-Include-Trybots: luci.dart.try:vm-kernel-win-release-x64-try,vm-kernel-optcounter-threshold-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-win-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/67345
Commit-Queue: Samir Jindel <sjindel@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
This is a cut of the work that Todd and I collaborated on in the reload branch.
In this CL, we've dropped the loader port hacks, in other words, on stack reloading in the standalone embedder does not work yet.
- [x] Support for hot reloading of isolate source code
- [x] Unit test harness and many tests
- [x] Service protocol and Observatory support
- [x] Product build does not include support for hot reloading.
R=rmacnak@google.com
Review URL: https://codereview.chromium.org/1965823002 .
- Use TokenDescriptor instead of intptr_t for all token positions.
- Use TokenDescriptor in raw_object instead of int32_t.
- TokenDescriptor is a POD with an int32_t (this shrinks the size of AST and IR nodes by 32-bits on 64-bit architectures).
There are some cleanups I plan on doing as a follow up CL:
- Replace TokenDescriptor::value() with TokenDescriptor::TokenPos()
R=iposva@google.com, rmacnak@google.com
Review URL: https://codereview.chromium.org/1644793002 .
- Rework token position address space.
- Use ClassifyingTokenPositions::kMethodExtractor for the token position of a method extractor.
- Plumb token positions through all of Ast Transformer.
- Plumb token positions for temporary expressions, etc in Flow Graph Builder.
- Add token positions for parts of the await machinery.
- Move ClassifyingTokenPositions into token.h.
- Remove default token position of Scanner::kNoSourcePos for many IR instructions.
- A couple of unit tests.
- Use synthetic token positions for synthetic AstNodes.
- Fix SLEB128 encoding / decoding + test
- s/Scanner::kNoSourcePos/Token::kNoSourcePos.
- Remove >= 0 and < 0 checks against token positions and use helpers instead.
R=rmacnak@google.com
Review URL: https://codereview.chromium.org/1589643002 .
This change makes CTX available by not caching the current
context while in Dart code. Instead the current context
is held in a local variable (:saved_current_context_var) and
is passed as argument in CTX at calls.
This also simplifies a lot of code in the debugger: As a result,
Isolate::top_context is not needed anymore since the current context
can always be extracted from a Dart frame.
R=vegorov@google.com
Review URL: https://codereview.chromium.org//678763004
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@41422 260f80e4-7a28-3924-810f-c04153c831b5
By moving all stubs that do runtime calls into the isolate
we don't need to cache the current isolate in each context
object.
This saves space on each context at the cost of duplicating stubs
in each isolate. Most stubs are already isolate-specific and the total number
of stubs is small enough for this to be a good trade-off.
R=vegorov@google.com
Review URL: https://codereview.chromium.org//668193002
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@41279 260f80e4-7a28-3924-810f-c04153c831b5
Until now the parser marked native functions as native when parsing.
This may be too late for some functions. E.g. the native typed list
constructor may not be invoked because the intrinsic code is executed
instead (unless for example new-space allocation fails).
This causes missing type information when optimizing functions using
those recognized factory functions like Uint8List._new.
R=srdjan@google.com
Review URL: https://codereview.chromium.org//99373002
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@30846 260f80e4-7a28-3924-810f-c04153c831b5