Instead of depending on all canonical clusters being written first,
followed by all non-canonical clusters, mark whether a cluster is
canonical or not in its written form. This allows future changes to
interleave canonical and non-canonical clusters as needed.
TEST=Existing tests, as this is purely a refactoring.
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-dwarf-linux-product-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64c-try,vm-kernel-precomp-nnbd-linux-debug-x64-try
Change-Id: I0ab835c262e061ffd3dd93be0c8f5358c9b51fc2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/195994
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
This is a reland of 5909fd111d
Does a large refactoring on the V8 snapshot profile writer
to clean things up, add more debugging support, and to fix
the problems that surfaced during the original landing.
Other changes:
Changes Serializer::CreateArtificialNodeIfNeeded() to create
artificial nodes for Code objects and immutable arrays.
Fixes CodeSerializationCluster::Trace() to only push needed parts of
discarded code objects, instead of tracing them like full code objects.
Adds test cases to v8_snapshot_profile_writer_test that exercise
the following situations (both separately and together):
* Non-symbolic stack traces are enabled and code and function objects
are dropped when not needed at runtime.
* Creation of the dispatch table is disabled.
TEST=vm/dart{,_2}/v8_snapshot_profile_writer_test
Original change's description:
> [vm] Fix V8 snapshot profile handling of the dispatch table.
>
> Fixes https://github.com/dart-lang/sdk/issues/45702.
>
> TEST=Tests listed in the issue above.
>
> Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try
> Change-Id: Ibf5e3ccf3828c01f9dda47de360314dabe8cb8a9
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/195272
> Reviewed-by: Daco Harkes <dacoharkes@google.com>
> Commit-Queue: Tess Strickland <sstrickl@google.com>
Change-Id: I8e7030267fe190079a8f68d00fe20bf7170e5719
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/195513
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
Instead of special-casing the current fields that may have
WeakSerializationReferences, handle WSRs appearing as elements
or properties of objects more generally. This removes existing
special casing and avoids the need for it in case of new
future uses of WSRs.
For artificial nodes being added for dropped
WeakSerializationReference targets, add them as kArtificial nodes
(not kSnapshot) that has the original offset (element) or
name (property). The replacement is added as a kSnapshot node
that has a negative offset with the same magnitude as the
artificial node (element) or ":real_<property name>" (property).
This simplifies the work done in pkg/vm_snapshot_analysis to
use the artificial nodes instead of replacement ones for
reassembling hierarchies and the like.
This CL also cleans up the old SerializerWritingObjectScope
class, both moving it to Serializer::WritingObjectScope and
allowing nesting of WritingObjectScopes with the correct
semantics.
Thanks to this, not only can we recur when under a WritingObjectScope
instead of lifting recursion outside of those scopes, but we can
also create artificial nodes for non-empty per-code object pools and
static call target tables instead of attributing their contents
as supposed elements of the Code object being written.
TEST=pkg/vm_snapshot_analysis/test/instruction_sizes_test
Cq-Include-Trybots: luci.dart.try:pkg-linux-release-try,pkg-mac-release-try,pkg-win-release-try
Change-Id: Ib945c5afcd89b1458b8be3559b6eae24048aba2f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/194243
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
While deserializing AOT snapshot, Code objects which do not contain
valuable information besides entry point and stack maps are discarded
and not allocated on the heap (they are replaced with
StubCode::UnknownDartCode()).
PC -> Code/CompressedStackMaps lookup is implemented using a separate
table (InstructionsTable).
Flutter gallery in release-sizeopt mode:
Heap size of snapshot objects: arm -26.89%, arm64 -27.68%
Large Flutter application in release mode with --dwarf-stack-traces:
Heap size of snapshot objects: -24.3%.
Discarded Code objects: 72.5% of all Code objects.
Issue: https://github.com/dart-lang/sdk/issues/44852.
TEST=existing tests; "--dwarf_stack_traces --no-retain_function_objects
--no-retain_code_objects" mode is enabled for a few tests.
Change-Id: I5fe3e283630c8e8f4442319d5dcae38d174dd0d8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/189560
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Creates HasParent() as a predicate for Function objects with a non-null
parent function and makes IsLocalFunction() specific to local closures
(i.e. explicit closures with non-null parent functions).
Creates HasSavedArgumentsDescriptor() as a predicate to determine when
saved_args_desc() can be used, to avoid the caller having to do explicit
predicate checks for each dispatcher type that contains one.
Also simplifies Function::PrintName, creates different suffixes for a
SyncGenClosureMaker and its associateed SyncGenClosure, adds suffixes
for skipping more than one generated body when printing the parent name,
and changes ArgumentsDescriptor::PrintTo to match the compact syntax
Function::PrintName used for signifying the arguments descriptor for
certain dispatchers.
TEST=pkg/vm_snapshot_analysis/test/instruction_sizes_test
Cq-Include-Trybots: luci.dart.try:app-kernel-linux-release-x64-try,vm-kernel-precomp-linux-release-x64-try,pkg-linux-release-try
Change-Id: I0ac1226d1ffe1d81743b5c6788da170d5a4010c5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/191560
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
The following are not compressed: Code, ObjectPool, Context, CallSiteData and subclasses.
Code::instructions_ is uncompressible because the VM doesn't control the address of Instructions when they are loaded via dynamic library.
Loads from the ObjectPool are a frequent occurrence in generated code, and shrinking ObjectPool entries would be offset by longer code sequences to decompress them. Also, some ObjectPool entries contain uncompressible pointers to C functions.
Context is not compressed based on reports from earlier work on compressed pointers that compressing them is disproporately bad for performance. The earlier work used a different, more-expensive compression scheme, so we should reinvestigate this.
CallSiteData et al. are on the hot path for unoptimized code but make up a comparatively small portion of the heap size.
TEST=ci
Change-Id: I9a425fa4e12113c9fd0b51999525d32a7e589a90
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/190600
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Liam Appelbe <liama@google.com>
This CL changes how canonical sets for some specific types are written
into the root snapshot: instead of writing canonical set as a separate
object we reorder objects within a canonical cluster in such a way that
the order matches order of elements in the backing store of a canonical
set and then we write canonical set layout out using differential
encoding (essentially writing gaps between elements instead of writing
absolute indices).
This significantly reduces the overhead of having canonical sets in the
snapshot while maintaining fast deserialisation: for example on build
microbenchmark this brings regression in the snapshot size from 4% to
.3%.
On sizeopt benchmarks:
flutter_gallery_app_so_gzip_size -1.5%
flutter_gallery_app_so_size -4.7%
flutter_gallery_total_heap_size -16.2%
TEST=ci
Change-Id: I2be7fd073668e9b52098e2acda9f11d128cfda95
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-dwarf-linux-product-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-linux-debug-x64-try,pkg-linux-release-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/185381
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
This statistics is printed with --print_snapshot_sizes_verbose.
It is useful in order to figure out how much memory is consumed by
program structure objects without running an application.
TEST=manual testing with --print_snapshot_sizes_verbose
Change-Id: I6eeae7b303ecaf44806deb0f532058492c1d5808
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/181444
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Currently we have things called XPtr which are not what you get from ptr().
Old world:
handle->raw() returns RawObject* (tagged)
raw_obj->ptr() returns RawObject* (untagged)
After 6fe15f6df9:
handle->raw() returns ObjectPtr
obj_ptr->ptr() returns ObjectLayout*
New world:
handle->ptr() returns ObjectPtr
obj_ptr->untag() returns UntaggedObject*
TEST=ci
Change-Id: I6c7f34014cf20737607caaf84979838300d12df2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149367
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
This is a step toward deferring literals, to effectively split binary size for libraries that are more data than code, such as localizations. Bare instructions mode still has all constants in the root snapshot because it has one global ObjectPool.
dart2js+analyzer product X64 non-bare:
app.so 10072728 -> 8479824 (-15.8%)
app.so-2.part.so 14074512 -> 15016976 (6.69%)
app.so-3.part.so 9225936 -> 9888984 (7.18%)
TEST=ci
Bug: https://github.com/dart-lang/sdk/issues/41974
Change-Id: If61f6156e3fc2dd539331335b3bf0458102b7c75
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/168991
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Régis Crelier <regis@google.com>
As part of making the compiler and other subsystems independent
of `Isolate` we have to move various state from `Isolate` to
`IsolateGroup`.
The class_table and object_store were already moved to `IsolateGroup`.
This CL only replaces usages of `Isolate::{object_store,class_table}`
with the equivalent in `IsolateGroup`.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Pure refactoring - relying on existing test coverage.
Change-Id: I34a0682d715b054d6c5faff077a513980f59a348
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177126
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Instead, split each old use into the following cases:
* If the TokenPosition value is expected to be a real token position,
then use TokenPosition::Pos().
* If the TokenPosition is being serialized in some way, then use
TokenPosition::Serialize() and change the place where the
TokenPosition is recreated to use TokenPosition::Deserialize().
* If the value of the TokenPosition is being printed for debugging
purposes, then just use TokenPosition::ToCString() instead.
That is, we try to pin down when token positions are expected to
be real vs. when other types of token positions can be found.
Another source of possible error when using token positions is to
convert between synthetic and real token positions. In the past,
synthetic token positions may have been based off real token positions,
but that is no longer the case. Thus, all methods that allow
that conversion have been removed, and instead there is a new static
method for constructing synthetic tokens from valid nonces.
This CL also makes it so that Pos() and relational operators on token
positions are only defined on real token positions, to avoid any
assumptions about what the value encoded in synthetic positions mean. To
help with cases where non-real token positions may occur, four helper
methods are added:
* TokenPosition::Min(a, b): A static method that returns the smallest
real token position provided. If neither `a` or `b` are real,
returns `a`.
* TokenPosition::Max(a, b): A static method that returns the largest
real token position provided. If neither `a` or `b` are real,
returns `a`.
* TokenPosition::IsWithin(start, end): Determines whether `this` falls
between `start` and `end` (inclusive). If `this` is non-real, then it
must be either `start` or `end` if synthetic, otherwise false.
Otherwise, we mimic the old style of range checking, which means that
non-real starts and ends are treated as less than every real token.
* TokenPosition::CompareForSorting(other): Unlike the relational
operators, provides a comparison between any types of token positions
for purposes such as sorting. Currently only used in the profiler.
It also changes TokenPosition::ToCString() to tag synthetic token
positions, so they can be distinguished from real ones at a glance.
TEST=Existing test suite on trybots, especially the observatory tests
which make heavy use of the debugger and the unit tests for the
profiler/source report modules.
Bug: https://github.com/dart-lang/sdk/issues/44436
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-nnbd-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-nnbd-linux-debug-x64-try,vm-kernel-linux-debug-x64-try,vm-kernel-linux-release-x64-try,vm-kernel-nnbd-linux-release-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-nnbd-linux-release-x64-try,vm-kernel-linux-product-x64-try,vm-kernel-precomp-linux-product-x64-try
Change-Id: Ic06aa0bc7a1f0fbac7257ed22ca5e7e0ccd7f3f2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/174924
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
As part of making lightweight isolates work in JIT, we will need to
ensure that whenever a new isolate is spawned it will get it's initial
global field table populated.
In order to achieve this we make the isolate groups initial field table
the authoritive place where we
a) register initial static field values
b) serializer reads them from, deserializer writes them to
This allows us to also remove the `FieldLayout::initial_saved_value_`
that was present for both static and non-static fields. In reality this
initial saved value is only meaningful for static fields though it was
kept in memory as well as (de)serialized even for non-static fields.
The one place where it was actually used for non-static fields was
incorrect and should instead use `null`.
The removal of this field results in net removal of code in this CL.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Internal refactoring, relying on existing test coverage.
Change-Id: I088a87e2ea159bac7fa7f1f360da553d752e6569
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/173263
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
This partially undoes changes from acbd51c08
because they are now known to increate RSS of AOT
compiled applications.
This CL also removes length adjustment code from *String::InstanceSize
which tried to ensure that external string fits into a non-external
string. This code is no longer necessary because APIs for
string externalization were removed.
TEST=covered by the existing tests
Cq-Include-Trybots: luci.dart.try:app-kernel-linux-release-x64-try,app-kernel-linux-debug-x64-try,vm-kernel-nnbd-linux-debug-x64-try,vm-kernel-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-nnbd-linux-debug-x64-try
Change-Id: Ife4f16d6939d98bb7966121b5899cef9f0121220
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/170080
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Allow weak tables to contain immediate objects (Smis) by adjusting the sentinel value for an empty entry to a value which is never a valid Smi nor heap object. Immediates go into the old-space table, since they also don't need to be updated after a scavenge.
Remove the clustered serializer's separate Smi id table.
Change-Id: Ia34ebe92be17f6568f0d4e5090e9abf5e77dadb3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/168620
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
All *WriteStream classes are now part of the same hierarchy:
class BaseWriteStream : ValueObject;
Base class for all *WriteStreams. Provides all the methods from
the old WriteStream except for buffer() and SetPosition()
(relegated to NonStreamingWriteStreams). Has one pure virtual
method Realloc that must be overridden by concrete subclasses.
class NonStreamingWriteStream : BaseWriteStream;
Base class for all *WriteStreams where the entire stream is available
at all times (i.e., no flushing to an external sink). Extends the
public BaseWriteStream API with buffer() (for accessing the stream
contents) and SetPosition() (for changing the current stream pointer
to the given absolute position in the stream).
class MallocWriteStream : NonStreamingWriteStream;
Uses realloc to reallocate the internal buffer. Almost the same as
the old WriteStream, except that it only takes an initial size. Adds
one public method Steal() for taking ownership of the current buffer
contents (after which the buffer is reset to an empty state). Instead
of passing a pointer to a buffer, the internal buffer must be accessed
via either Steal() or buffer(), which allows access to the current
stream contents without changing ownership or resetting the stream.
The internal buffer is freed on stream destruction.
class ZoneWriteStream: NonStreamingWriteStream;
Takes a zone and reallocates the internal buffer in that zone. No
additional public methods beyond those available from
NonStreamingWriteStream.
class StreamingWriteStream : BaseWriteStream;
Uses realloc to reallocate the internal buffer. Generally same as
before, where the contents of the stream are periodically flushed
using Dart_StreamingWriteCallback. Since it extends BaseWriteStream,
there are now more methods available for writing data to the stream
than just Print/VPrint/WriteBytes. Since portions of the stream may be
flushed and thus no longer in the internal buffer, does not provide
access to the contents of the stream or a way to reposition the
current stream pointer. Flushes any unflushed data and frees the
internal buffer on stream destruction.
Also refactor things so that write streams are passed to appropriate
recipients, instead of the recipients taking arguments they only used to
create a WriteStream internally. Thus, recipients now can just specify
the appropriate base class for the public API used:
* BaseWriteStream for just writing to the stream, or
* NonStreamingWriteStream if re-positioning or the stream contents are
needed.
Change-Id: I419096ecd9331483d168b079fca55b69ef397f15
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/164080
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Prevents snapshots from including canonical strings and types with no real uses and only referenced from the canonical tables.
Prep for constants not all being in the root snapshot during snapshot splitting, which is why we fill the table during load instead of rebuilding tables during snapshot writing.
Removes the size of the tables from the snapshot.
flutter_gallery_app_so_size (Pixel 2) -1.618% 7967664 8098736
flutter_gallery_app_so_gzip_size (Pixel 2) -2.724% 2980344 3063788
flutter_gallery_app_so_brotli_size (Pixel 2) -3.530% 2561824 2655566
Bug: https://github.com/dart-lang/sdk/issues/41974
Bug: https://github.com/dart-lang/sdk/issues/43319
Change-Id: I4f3b62da1cea9ee17caa965e809f16856518c9a6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/164102
Reviewed-by: Régis Crelier <regis@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
When reading a secondary snapshot, re-run the dispatch table initialization found in the root snapshot. Since each loading unit's contribution to the dispatch table is scattered, it would take more snapshot size to try to serialize their contributions separately. We'll revisit this when we can defer Class, Function and Code, which will prevent the root snapshot from referencing all Codes.
Bug: https://github.com/dart-lang/sdk/issues/41974
Change-Id: Iefd2b98647b96ae59a7efe92897538f5cf8c2426
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/158923
Reviewed-by: Aske Simon Christensen <askesc@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
- Don't use PC-relative calls when calling between loading units.
- Sort the contents of the code cluster by loading unit, then by text offset.
- Handle binding PC-relatives calls and inserting trampolines per loading unit.
- Create one code order table per loading unit to implement PC -> Code lookup.
- Read code order tables directly, instead of copying into malloc'd memory.
--use_table_dispatch still not yet supported.
This slightly shrinks non-split binaries (~2% clustered part, 0.4% total snapshot) due to the new delta encoding when Code references Instructions.
Bug: https://github.com/dart-lang/sdk/issues/41974
Change-Id: I51052ebc7b4968b554897d1710135a6c41821302
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/157820
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
(Assignment of libraries to loading units is already done in the kernel generation step.)
After compiling and before serializing, we walk the program and for each Code we assign its Instructions, CodeSourceMap and CompressedStackMap to the loading unit of that Code's defining library. Deduplication may cause Instructions, CodeSourceMaps and CompressedStackMaps to belong to more than one loading unit; in this case the objects are assigned to the root loading unit. Later they can be more precisely assigned to the dominating loading unit.
All objects except some Instructions, CodeSourceMaps and CompressedStackMaps belong to the root loading unit's snapshot. This snapshot is written like an unsplit snapshot, except that when serializing Code, we will write a reference to a stub or null when the Code's Instructions, CodeSourceMap or CompressedStackMap belongs to a non-root loading unit. The snapshots of non-root loading units contain these deferred objects and references to the corresponding Code objects to patch. The types of objects we defer (Instructions, CodeSourceMaps and CompressedStackMaps) usually represent 70+% of the snapshot size.
Bare instructions mode must be disabled when splitting because we cannot have PC-relative calls between loading units. Later we can re-enable this for calls within loading units.
Broken: Compactor probably crashes we can now have an unbounded number of image pages and the compactor assumes a fixed number.
Embedder's guide:
At compile-time, gen_snapshot should be passed --loading_unit_manifest with a path, which will enable splitting and output a mapping from loading unit ids to snapshot output paths.
At runtime, sometime during isolate startup, an embedder should call Dart_SetDeferredLoadHandler, probably near an existing call to Dart_SetLibraryTagHandler. The callback is given a loading unit id, and should eventually call Dart_DeferredLoadComplete[Error].
Bug: https://github.com/dart-lang/sdk/issues/41974
Change-Id: Ib597eb87c8cd634416d5ee1f00629c5550aebb00
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/152427
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Right now we assign class ids to top-level classes, abstract classes as
well as concrete classes. All of them have allocated from a 16-bit pool
of ids. The VM FATAL()s once it hits that limit.
Customers who run very large programs (significant amount of generated
code) on the Dart VM have started to hit this 16-bit class limit.
Concrete classes can have instances in the heap. Our current heap layout
only allows 16-bit class ids to be encoded in the header word. To avoid
increasing the size of heap objects or shrinking the size of the identity
hash code to 16-bit we keep class ids in object headers to be 16-bit.
Abstract classes cannot have instances in the heap. Though their class
ids are encoded in type objects. Furthermore we sort classes in
AOT/AppJIT mode to perform fast class-id range checks. To avoid impacting
this optimization we treat abstract classes the same way as concrete
classes.
Top-level classes cannot have instances in the heap. Their class ids are
only used in the runtime code, for example for hot-reload as well as
part of the service protocol.
=> We can allocate class ids outside the 16-bit range for top-level
classes, thereby freeing a significant amount of space in the 16-bit
range.
This CL does exactly that: We change classid_t to be int32_t. The
ClassLayout::id_ can now be assigned ids outside 16-bit range for
top-level classes. To do this we keep dart classes and top level classes
as separate arrays in the ClassTable.
Issue https://github.com/dart-lang/sdk/issues/42533
See also b/160229360
Change-Id: I6710a644e7b0ab2d4f4c792bef8e1f91cb117421
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/153607
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
- Detect null safety when not specified before isolate
initialization
- for source files by having CFE parse the source file
for @dart annotations
- for kernel files by sniffing the kernel file for
compilation mode
- for appJIT files by sniffing the feature string
- for AOT snapshots by sniffing the feature string
- Remove workaround of returning null safety to false during
bootstrapping
- Add a new Dart C API call for detecting null safety
Bug: 41766
Change-Id: Ia8cf264323a2d0d58c2855ce6491456aa6f1da07
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/150089
Commit-Queue: Siva Annamalai <asiva@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Snapshots don't necessarily retain original program structure because we
attempt to drop objects representing elements of the program structure
when it is not observable. However not having this information makes it
harder to understand how various parts of the snapshot graph relate to
the original program.
This CL introduces support for writing artificial nodes into snapshot profile
for the cases when we want to preserve some structure for later analysis.
To make mapping between actual heap objects and their artificial profile
counterparts simple we use currently unutilized part of the object-id space:
negative ids below kUnallocatedReference.
https://github.com/dart-lang/sdk/issues/41249
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Change-Id: Idb46491b0e2b21aebf946b0da55eaf67e73aadd6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/148530
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
This reverts commit 922ea3e9b6 in patchset 1, fix for assertion triggered in https://ci.chromium.org/b/8883214567628884960 in patchset 2, fix for deadlock around symbols table mutex in patchset 4.
Original commit description:
Speed up is achieved by sharing most of the dart code, object store
and class table between isolates in single isolate group. So
instead of bootstrapping isolate from the snapshot, isolate is
initialized by setting pointers to existing data structures already
set up for first isolate, and only few isolate-specific structures (moved
to newly introducted isolate_object_store) are created.
To allow for safe cross-isolate switchable call site, type test cache
mutations additional synchronization via RunWithStoppedMutators(that
relies on safepoints) was added.
Besides switchable call sites, no other mutation to the dart code is
done in AOT, which allows such sharing.
Bug: https://github.com/dart-lang/sdk/issues/37835
Bug: https://github.com/dart-lang/sdk/issues/36097
Change-Id: I655e337198214c9dfacbe76f7852b941b5a7e910
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/143462
Commit-Queue: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Original revert in patchset 1, fix for deadlock issue in patchset 2: avoid reentrant calls to RunWithStoppedMutator.
Further review comments addressed in successive patchsets.
This reverts commit 8ef508ba36.
Original commit description:
Speed up is achieved by sharing most of the dart code, object store
and class table between isolates in single isolate group. So
instead of bootstrapping isolate from the snapshot, isolate is
initialized by setting pointers to existing data structures already
set up for first isolate, and only few isolate-specific structures (moved
to newly introducted isolate_object_store) are created.
To allow for safe cross-isolate switchable call site, type test cache
mutations additional synchronization via RunWithStoppedMutators(that
relies on safepoints) was added.
Besides switchable call sites, no other mutation to the dart code is
done in AOT, which allows such sharing.
Change-Id: I6a0279d9812020ad7a5c2b7851980b6a29b95b9a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/143327
Commit-Queue: Alexander Aprelev <aam@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Speed up is achieved by sharing most of the dart code, object store
and class table between isolates in single isolate group. So
instead of bootstrapping isolate from the snapshot, isolate is
initialized by setting pointers to existing data structures already
set up for first isolate, and only few isolate-specific structures (moved
to newly introducted isolate_object_store) are created.
To allow for safe cross-isolate switchable call site, type test cache
mutations additional synchronization via RunWithStoppedMutators(that
relies on safepoints) was added.
Besides switchable call sites, no other mutation to the dart code is
done in AOT, which allows such sharing.
Bug: https://github.com/dart-lang/sdk/issues/37835
Bug: https://github.com/dart-lang/sdk/issues/36097
Change-Id: I64c86525f4ef9cb30567a49a106bfe700355942b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/136780
Commit-Queue: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
In particular, don't serialize a function if its code is used by the
dispatch table, but there's no need for the function object itself
at runtime like dynamic lookup or dynamic invocation forwarders.
However, just because the owning function is not needed at runtime,
it may be used during serialization for things like assembly label
creation. Thus, instead of just clearing out the Code's owner field,
we add a new WeakSerializationReference (WSR) object whose target is
the original contents of the owner field. The WSR allows the
serializer to access the original owner, but also signals to the
serializer that the target should not be serialized in AOT snapshots
unless there are additional strong (non-WSR) references.
If no strong references are found, then the references to the WSR
in the snapshot are replaced with a reference to a WSR that only
contains the class ID of the original target. The serializer creates
only one WSR per class ID.
If strong references are found, then the target is still serialized.
In this case, the WSR is dropped entirely and any reference to it is
replaced with a direct reference to the serialized target. Thus, WSRs
only exist in the precompiled runtime for targets with no strong
references.
Changes on the Flutter gallery in release mode:
arm7: total size -1.10%, isolate size -6.08%
arm8: total size -1.16%, isolate size -6.09%
Bug: https://github.com/dart-lang/sdk/issues/41052
Change-Id: I5b435ca71ef85f50fe3484789087471a91aa4fe2
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/137104
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
These changes were originally submitted separately on different days,
and a major performance regression was seen after the first change
when creating snapshots that led to both being reverted. However,
that performance regression should be addressed by the followup.
First change:
"[vm] Treat the dispatch table as a root in the snapshot.
Additional changes:
* Only serialize a dispatch table in precompiled snapshots.
* Add information in v8 snapshot profiles for the dispatch table.
* Fix a typo in a field name.
* Print the number of Instructions objects (or payloads, for
precompiled bare instructions mode) in the fake cluster for
the data section.
* Fix v8 snapshots profiles so objects in memory mapped segments
and only those are prefixed with "(RO) ".
* Add names for Instructions objects in v8 snapshot profiles
when we can use the assembly namer.
* Add command line flag for old #define'd false flag."
Second change:
"[vm/aot] Keep GC-visible references to dispatch table Code entries.
This change splits dispatch table handling into four distinct
parts:
* The dispatch table generator does not make a dispatch table
directly, but rather creates an Array that contains the Code
objects for dispatch table entries.
* The precompiler takes this Array and puts it in the object
store, which makes it a new GC root.
* The serializer takes this information and serializes the
dispatch table information in the same form as before.
* The deserializer creates a DispatchTable object and populates
it using the serialized information.
The change in the precompiler ensures that the Code objects
used in the dispatch table have GC-visible references. Thus,
even if all other references to them from the other GC roots
were removed, they would be accessible in the serializer in
the case of a GC pass between the precompiler and serializer.
This change also means that the serializer can retrieve and
trace the Code objects directly rather than first looking up
the Code objects by their entry point."
Bug: https://github.com/dart-lang/sdk/issues/41022
Change-Id: I52c83b0536fc588da0bef9aed1f0c72e8ee4663f
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Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/139285
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
This change splits dispatch table handling into four distinct
parts:
* The dispatch table generator does not make a dispatch table
directly, but rather creates an Array that contains the Code
objects for dispatch table entries.
* The precompiler takes this Array and puts it in the object
store, which makes it a new GC root.
* The serializer takes this information and serializes the
dispatch table information in the same form as before.
* The deserializer creates a DispatchTable object and populates
it using the serialized information.
The change in the precompiler ensures that the Code objects
used in the dispatch table have GC-visible references. Thus,
even if all other references to them from the other GC roots
were removed, they would be accessible in the serializer in
the case of a GC pass between the precompiler and serializer.
This change also means that the serializer can retrieve and
trace the Code objects directly rather than first looking up
the Code objects by their entry point.
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Change-Id: Ic9ba29dfd64945a6e9a51f9de73f74d9202b58b7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/138288
Commit-Queue: Teagan Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Aske Simon Christensen <askesc@google.com>
Tess Strickland