This is the final CL which adds a new --use-bare-instructions flag to
the VM.
If this flag is set during AOT compilation, we will:
* Build one global object pool (abbr: GOP) which all code objects
share. This gop will be stored in the object store. The PP register
is populated in the enter dart stub and it is restored when
returning from native calls.
* Gets rid of the CODE_REG/PP slots from the dart frames. Instead the
compiled code uses the global object pool, which is always in PP.
* Starts emitting pc-relative calls for calls between two dart
functions or when invoking a stub.
Limitation: We only emit pc-relative calls between two code objects
in the same isolate (this is because the image writer is writing
instruction objects for vm-isolate/main-isolate seperately)
* We do compile-time relocation of those static calls after the
precompiler has finished its work, but before writing the snapshot.
This patches all the instruction objects with pc-relative calls to
have the right .text distance.
* We emit a sorted list of code objects in ObjectStore::reverse_code_table,
which will be used by the AOT runtime to go back from PC to Code
objects (where all metadata, e.g. stack maps, catch entry moves, pc
descriptors are available).
Issue https://github.com/dart-lang/sdk/issues/33274
Change-Id: I6c5dd2b1571e3a889b27e804a24c2986c71e03b6
Reviewed-on: https://dart-review.googlesource.com/c/85769
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
In Dart2, type bounds checking is either performed by the common front-end or
by explicitly generated code, but not by type finalization or runtime anymore,
as it was done in Dart1.
Consequently, the class BoundedType is not needed anymore, and malbounded or
malformed types are not seen by the runtime either.
Change-Id: I5d6e4c68d153d6730fa7ff7f6d9dcfa611299c16
Reviewed-on: https://dart-review.googlesource.com/c/86687
Commit-Queue: Régis Crelier <regis@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Samir Jindel <sjindel@google.com>
When GC is visiting pointers, it scans mutator thread even if it is not
active. It could happen if a thread has (temporarily) exitted isolate.
In such case, stack frame iteration would not find interpreter and
would not recognize interpreter frames. An attempt to visit interpreter
frame as non-interpreter causes crashes/assertions.
The fix is to move interpreter from Isolate to Thread. This way
interpreter is available for stack walking even if thread doesn't have
isolate.
This is the re-land of https://dart-review.googlesource.com/c/sdk/+/80760
with the fix for precompiler failures.
Change-Id: I1fa054d43b86aa49c48490d0951b876b7c7218d8
Reviewed-on: https://dart-review.googlesource.com/c/80782
Auto-Submit: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Régis Crelier <regis@google.com>
This reverts commit a0cc3e2684.
Reason for revert: broken precompiler bots
Original change's description:
> [vm/interpreter] Fix interpreter frame recognition in stack walking
>
> When GC is visiting pointers, it scans mutator thread even if it is not
> active. It could happen if a thread has (temporarily) exitted isolate.
> In such case, stack frame iteration would not find interpreter and
> would not recognize interpreter frames. An attempt to visit interpreter
> frame as non-interpreter causes crashes/assertions.
>
> The fix is to move interpreter from Isolate to Thread. This way
> interpreter is available for stack walking even if thread doesn't have
> isolate.
>
> Change-Id: Iff12ce7391b19a6f87bd4fac94137cba5623dfb9
> Reviewed-on: https://dart-review.googlesource.com/c/80760
> Reviewed-by: Régis Crelier <regis@google.com>
> Commit-Queue: Alexander Markov <alexmarkov@google.com>
TBR=rmacnak@google.com,alexmarkov@google.com,zra@google.com,asiva@google.com,regis@google.com
Change-Id: Ic4d73536eadb6601ee323918c65f5f2b2b2b2418
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/80781
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
When GC is visiting pointers, it scans mutator thread even if it is not
active. It could happen if a thread has (temporarily) exitted isolate.
In such case, stack frame iteration would not find interpreter and
would not recognize interpreter frames. An attempt to visit interpreter
frame as non-interpreter causes crashes/assertions.
The fix is to move interpreter from Isolate to Thread. This way
interpreter is available for stack walking even if thread doesn't have
isolate.
Change-Id: Iff12ce7391b19a6f87bd4fac94137cba5623dfb9
Reviewed-on: https://dart-review.googlesource.com/c/80760
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Previously we tried to rely on the assumption that all variables would be
boxed - so the machinery for setting correct catch-entry state only
supported tagged values and constants. However this both leads to worse code
and is not entirely correct assumption.
This also:
- renames various confusingly named classes: we move away from talking
about "catch entry state" to "catch entry moves" - because we only
record a subset of moves that needs to be performed and that does
not describe the whole state;
- refactors a bunch of associated code to be more readable and maintainable;
- adds documentation about catch implementation in optimized code
to runtime/docs/compiler;
Fixes https://github.com/flutter/flutter/issues/21685.
Change-Id: I03ae361a1bb7710acbd9f661ae014e663a163c59
Reviewed-on: https://dart-review.googlesource.com/74860
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
After this CL, the interpreter is included by default in the
JIT VM under the flag --enable-interpreter.
Reland with fix to NativeArgument setup in simulator_arm.cc
Change-Id: Ib9b4df6eb4d997dfbe361188b8a127828c1d9c6f
Reviewed-on: https://dart-review.googlesource.com/74003
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Zach Anderson <zra@google.com>
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>
The safestack stack pointer is cached when invoking Dart code, and
manually restored when jumping over C++ frames for Dart exceptions
in Exceptions::JumpToFrame().
fixes#31356
Change-Id: I71c2e86d1d4f24571dd618a5db06fd1277339ebc
Reviewed-on: https://dart-review.googlesource.com/23141
Commit-Queue: Zach Anderson <zra@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
I collected statistics for the sizes and capacities of growable arrays which are promoted to old-space or survive an old-space gc when running dart2js and Fasta. For these applications, the vast majority of arrays stay empty. More than half of the total object size of promoted backing arrays is backing for empty growable arrays.
Furthermore, since the overhead for an array is 3 words (header, type parameters and length), and object sizes are rounded up to an even number of words, we waste one word for all even-sized arrays.
This CL changes the growth strategy so that empty growable arrays are created with a shared, zero-sized array as backing, avoiding the allocation of a backing array if no elements are added. When the array needs to grow, it starts out at 3 and grows to double size plus one each time: 7, 15, 31, ...
A few places in the VM code need to handle these shared, zero-sized arrays specially. In particular, the Array::MakeArray function needs to allocate a new, empty array if its result is to be returned to Dart code.
Benchmarks suggest that the change improves memory usage by a few percent overall and does not significantly affect run time.
BUG=
R=erikcorry@google.com
Review-Url: https://codereview.chromium.org/2949803002 .
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 .
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 .
use of Bigint (see issue #28595).
A RangeError with the message "Integer operand requires conversion to Bigint" is
thrown when a Bigint gets allocated. However, parsing a Bigint literal in Dart
source will not throw the RangeError (as long as the literal is not used).
R=asiva@google.com
Review-Url: https://codereview.chromium.org/2708213004 .
This CL improves the stack traces that accompany exceptions. Whenever an
async function is entered, we remember how we got there. This is similar
in spirit to package:stack_trace but the implementation is more efficient
and memory usage can be more easily reasoned about.
Tracking causal stack traces:
- [x] Upon entry to an async function, capture the synchronous stack trace prefix and store it into the closure.
- [x] Upon entry to an async* function, capture the synchronous stack trace prefix and store it into the closure.
- [x] Before returning from an async function, clear the Thread's asynchronous stack trace.
- [x] After resuming an async function, load the sychronous stack trace prefix into the Thread.
- [x] Filter stack traces to remove async machinery.
Service protocol changes:
- [x] Send causal async stack trace.
Observatory changes:
- [x] Display causal async stack trace below async functions.
Fixes https://github.com/dart-lang/sdk/issues/27661R=asiva@google.com, rmacnak@google.com
Comparisons: https://docs.google.com/a/google.com/document/d/10r6jEqr8OCiDZ4y9SYU_uOimcHiOGAZMly2ghTErALI/edit?usp=sharing
Review-Url: https://codereview.chromium.org/2646443005 .
Martin Kustermann