Previously there were places in the code where an API accepted a
`bool validate_frames` and call sites passed an enum value (which
implicitly got converted to a bool).
By changing the APIs to require an enum, the compiler will tell us if a
caller doesn't pass one.
Change-Id: I29fcd0b018e6cdd7e00b5bb03e83b9636d1345d4
Reviewed-on: https://dart-review.googlesource.com/57823
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Improves the space overhead of compaction from O(size of live objects) to O(number of live objects).
Future work includes:
- a smaller, faster representation the forwarding table via a bitmap of used allocation units
- sorting class sizes off-heap to allow sliding classes
- running forwarding in parallel
Removes unnecessary sweep from evacuating compactor.
Change-Id: If0991bfb75573201c6e8feed142ca0cc69fccab4
Bug: https://github.com/dart-lang/sdk/issues/30978
Reviewed-on: https://dart-review.googlesource.com/15988
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Erik Corry <erikcorry@google.com>
The compactor copies all live objects in old space to fresh pages, places forwarding pointers in the old objects, forwards all the pointers, then frees the old pages. This has a high space overhead. It is not meant for use in production, but meant to test that the VM is properly set up to handle old-space objects moving.
Large page objects and instruction objects are not moved.
Bug: https://github.com/dart-lang/sdk/issues/30978
Change-Id: Ia42683fd5e27a33702aa5e83bece803a8b005a4b
Reviewed-on: https://dart-review.googlesource.com/13624
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Zach Anderson <zra@google.com>
Reviewed-by: Erik Corry <erikcorry@google.com>
We've been getting away with skipping this slot because
- ObjectPools are allocated into old space and never move, and
- the ObjectPools are also reachable from the PC marker in the caller's frame.
However, ObjectPools will become movable during compacting GCs.
Bug: https://github.com/dart-lang/sdk/issues/30978
Change-Id: Ied3a1588365fe5362ad7f1d2d446a7a59df6ced6
Reviewed-on: https://dart-review.googlesource.com/10680
Reviewed-by: Siva Annamalai <asiva@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
New folder structure (nested under vm/):
- compiler/
- jit/ - JIT specific code
- aot/ - AOT specific code
- backend/ - all middle-end and back-end code (IL, flow graph)
- assembler/ - assemblers and disassemblers
- frontend/ - front ends (AST -> IL, Kernel -> IL)
compiler/README.md would be the documentation root for the compiler
pipeline
Bug: https://github.com/dart-lang/sdk/issues/30575
Change-Id: I2dfd9688793bff737f7632ddc77fca766875ce36
Reviewed-on: https://dart-review.googlesource.com/2940
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
The assertions which tried to assert that we only use
StackFrameIterator to walk frames of the current thread was incorrect.
We already have cases where other threads will walk the stack of the
mutator thread, see below for an example where this can happen.
Thread::VisitObjectPointers was incorrectly passing Thread::Current() to
the StackFrameIterator instead of 'this'. (Code in thread_registry.cc will
loop over a number of threads and calls VisitObjectPointers on them)
Mutator thread:
0 pthread_cond_wait@@GLIBC_2.3.2
1 dart::Monitor::WaitMicros
2 dart::Monitor::Wait
3 dart::MonitorLocker::Wait
4 dart::ThreadBarrier::Sync
5 dart::GCMarker::MarkObjects
6 dart::PageSpace::MarkSweep
7 dart::Heap::CollectOldSpaceGarbage
8 dart::Heap::CollectNewSpaceGarbage
9 dart::Heap::CollectGarbage
10 dart::DN_HelperObject_<native>
11 dart::BootstrapNatives::<native>
<dart frames>
MarkTask thread:
1 dart::EntryFrame::VisitObjectPointers
2 dart::Thread::VisitObjectPointers <---- Walks mutator thread stack
3 dart::ThreadRegistry::VisitObjectPointers <---- Iterates over a number of threads
4 dart::Isolate::VisitStackPointers
5 dart::Isolate::VisitObjectPointers
6 dart::GCMarker::IterateRoots
7 dart::MarkTask::Run
8 dart::ThreadPool::Worker::Loop
9 dart::ThreadPool::Worker::Main
10 dart::ThreadStart
R=rmacnak@google.com
Review-Url: https://codereview.chromium.org/2845053003 .
One slot in each Dart frame contains a "pc marker". Prior to the calling convention change, the pc marker was a fixed offset from the code's entry point, from which the code object could be derived. After the change, the pc marker is a pointer to the code object itself.
R=asiva@google.com
Review-Url: https://codereview.chromium.org/2804793003 .
Like HOST_ARCH_*, HOST_OS_* describes the OS the VM is running on, which may be different from the OS the VM is generating code for during AOT compilation.
Currently we conflate the two when emitting AOT as assembly, and we get away with it because Flutter only uses assembly for targeting iOS and one can only target iOS from a Mac, but we expect to use assembly for Android as well so native tools can unwind Dart frames.
R=zra@google.com
Review-Url: https://codereview.chromium.org/2750843003 .
Use that to sync variables to predefined stack
slots inside of exception handler, not before
each MayThrow() instruction.
In JIT mode we can avoid storing extra metadata
by using deopt info instead.
Introduce caching of metadata and
exception handler based on PC.
R=fschneider@google.com, vegorov@google.com
Review-Url: https://codereview.chromium.org/2734323003 .
Use that to sync variables to predefined stack
slots inside of exception handler, not before
each MayThrow() instruction.
In JIT mode we can avoid storing extra metadata
by using deopt info instead.
Introduce caching of metadata and
exception handler based on PC.
R=fschneider@google.com
Review-Url: https://codereview.chromium.org/2640853002 .
The call sequence is very similar to a classic IC call, except the guarded class and the target are loaded indirectly from the constant pool instead of as immediates. In the monomorphic case, we call directly to the expected target with a class check in the callee. In the unlinked, polymorphic and megamorphic cases, we call a stub; these case are now call-through instead of call-and-return.
Every code, except stubs involved in switchable calls, includes the class check sequence at the beginning. So we now distinguish between a checked and an unchecked entry point. Generated code except the switchable call continues to use the unchecked entry point.
PC offsets are calculated relative to the beginning of the instruction stream, rather than either entry point.
BUG=
R=fschneider@google.com
Review URL: https://codereview.chromium.org/2226893002 .
Most of the infrastructure is fixed to work with DBC stack layout:
- register allocator allocates DBC registers with the limitation that we allocate only 20 registers and bail out if anything needs spilling (there is no use implementing spilling on DBC because registers are memory locations themselves). We should be able to bump number of CPU registers on DBC up to 256 but this requires major surgery in some parts - so I postponed this;
- lazy deoptimization is implemented, eager deoptimization is not - because we don't emit any code that actually requires it. it's a minor change to support it once we have a target;
- stack scanning respects stack maps built by registers allocator;
We bailout from all unsupported instructions.
R=zra@google.com
Review URL: https://codereview.chromium.org/1992963002 .
This undoes most of b2f3e8efe1.
This optimization prevents precompiled code from being disabled and re-enabled, because disabling causes the code to lose its only reference to its own instructions. This was okay for precompilated code that ran without a JIT because it is never disabled, but precompiled code that runs in a JIT will become disabled when corresponding optimized code is compiled and re-abled after a deopt.
R=fschneider@google.com
Review URL: https://codereview.chromium.org/1925153003 .
Reference Instructions only through Code::entry_point_ (or Function::entry_point_). Store the instructions size in its corresponding Code object.
precompiled dart2js x64 22163470 -> 21621102 (-2.45%)
R=fschneider@google.com
Review URL: https://codereview.chromium.org/1808553002 .
- 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 .
fields in a thread (i.e fields that are not Dart VM related)
- Split the Thread structure to be a pure Dart per thread structure and add
a pointer to os_thread which points to the OSThread structure
- Change Schedule/UnSchedule to set the Dart Thread structure as the TLS of
the thread when it is inside the Dart world and reset the TLS back to the
OSThread strcuture when is exits the Dart World.
- Moved the stack_base and few stack size related functions to OSThread from Isolate
R=johnmccutchan@google.com, zra@google.com
Review URL: https://codereview.chromium.org/1439483003 .
Instead of calling code object directly, call indirectly and
pass the code object in a register. The object pool is then loaded from
the code object. This is another preparation step for making generated code
relocatable.
All non-ia32 platforms:
No entry patching.
ARM:
PC marker (now code object) moves to the same place as on x64 (below saved PP, above saved FP).
R9 is now used as PP, R10 as CODE_REG.
BUG=
R=rmacnak@google.com
Review URL: https://codereview.chromium.org//1192103004 .
This adds meta-information to object pool entries to allow storing
untagged immediates or code addresses (ExternalLabel) directly.
This eliminates the need to generate extra code to preserve the LSB
when storing immediates as smis (x64, arm64).
BUG=
Review URL: https://codereview.chromium.org//1175523002.
Régis Crelier