Adds support for populating reference maps to the fast
register allocator. In order to calculate whether a stack slot
is live at a given instruction, we use the dominator tree to
build a bitmap of blocks which are dominated by each block.
A variable's spill operand is classed as alive for any blocks that are
dominated by the block it was defined in, until the instruction index
of the spill operand's last use. As such, it may be classified as live
down a branch where the spill operand is never used, however it is safe
since the spill slot won't be re-allocated until after it's last-use
instruction index in any case.
BUG=v8:9684
Change-Id: I772374599ef916f57d82d468f66429e32c712ddf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2298008
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69108}
Adds support for tracking the instruction range of spilled operands,
and then allocating spill slots to these ranges. It also adds some
unittests covering spill slot allocation.
Spill slots are allocated in a linear fashion, running through the
instruction stream in a linear order, ensuring that no spill operand
is allocated to a same spill slot that is already assigned to during
this whole start / end range. This isn’t optimal, since it doesn’t
take into account holes in these ranges (e.g, blocks between start
and end that aren’t dominated by the start), but in practice rarely
leads to more than one extra spill slot being allocated compared to
the current allocator.
BUG=v8:9684
Change-Id: Iedee7bcf552080e5b4b6a2f4e96b78b6c1396cab
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2297470
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69107}
Using uint8_t[] causes decay to pointer issue, which manifests in
copying garbage values in the call to WriteLittleEndianValue. Change it
to use a std::array, which doesn't have the decaying behavior.
Also add a regression test from comment#6 of the linked bug.
Bug: v8:10731
Change-Id: I4a1ca69fe99806642e9931625ca7aeab6663f955
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2316465
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69052}
Adds support for register allocation within a block to the fast
register allocator. Also adds some unittests covering basic
register allocation. No support yet for spill slot allocation,
so functions that spill don't work yet.
BUG=v8:9684
Change-Id: I91d0fc0660d7b65f59235242fd5e3b1a7618d813
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2297467
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69045}
... that controls whether the TF graph zones should support compression.
Bug: v8:9923
Change-Id: Ifbe237b75e9c92e62eb32b69d6b3b1a818269b83
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2308347
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69036}
The following adds support for JSMember through the existing
GlobalHandles implementation also used for TracedReference.
In addition, JSMember now supports set, clear, copy, move, comparison
and interaction with Local.
Bug: chromium:1056170
Change-Id: Ia50218bcfe4c056b3533a5b14eea954ade1da243
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2310357
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69028}
Design doc:
https://docs.google.com/document/d/1szInbXZfaErWW70d30hJsOLL0Es-l5_g8d2rXm1ZBqI/edit?usp=sharing
V8 can already collect data about how many times each basic block in the
builtins is run. This change enables using that data for profile-guided
optimization. New comments in BUILD.gn describe how to use this feature.
A few implementation details worth mentioning, which aren't covered in
the design doc:
- BasicBlockProfilerData currently contains an array of RPO numbers.
However, this array is always just [0, 1, 2, 3, ...], so this change
removes that array. A new DCHECK in BasicBlockInstrumentor::Instrument
ensures that the removal is valid.
- RPO numbers, while useful for printing data that matches with the
stringified schedule, are not useful for matching profiling data with
blocks that haven't been scheduled yet. This change adds a new array
of block IDs in BasicBlockProfilerData, so that block counters can be
used for PGO.
- Basic block counters need to be written to a file so that they can be
provided to a subsequent run of mksnapshot, but the design doc doesn't
specify the transfer format or what file is used. In this change, I
propose using the existing v8.log file for that purpose. Block count
records look like this:
block,TestLessThanHandler,37,29405
This line indicates that block ID 37 in TestLessThanHandler was run
29405 times. If multiple lines refer to the same block, the reader
adds them all together. I like this format because it's easy to use:
- V8 already has robust logic for creating the log file, naming it to
avoid conflicts in multi-process situations, etc.
- Line order doesn't matter, and interleaved writes from various
logging sources are fine, given that V8 writes each line atomically.
- Combining multiple sources of profiling data is as simple as
concatenating their v8.log files together.
- It is a good idea to avoid making any changes based on profiling data
if the function being compiled doesn't match the one that was
profiled, since it is common to use profiling data downloaded from a
central lab which is updated only periodically. To check whether a
function matches, I propose using a hash of the Graph state right
before scheduling. This might be stricter than necessary, as some
changes to the function might be small enough that the profile data is
still relevant, but I'd rather err on the side of not making incorrect
changes. This hash is also written to the v8.log file, in a line that
looks like this:
builtin_hash,LdaZeroHandler,3387822046
Bug: v8:10470
Change-Id: I429e5ce5efa94e01e7489deb3996012cf860cf13
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2220765
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69008}
v128.const (kExprS128) is the only constant expression supported
(similar to the other value types).
Bug: v8:10731
Change-Id: I9b11b47a851903dfd79d3590eff67b615057f81c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2308389
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Bill Budge <bbudge@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68975}
V8 already depends on cppgc_base which means that unittests does not
need to depend on cppgc_for_testing any longer.
Move the cppgc_for_testing dependency to the stand-alone
cppgc_unittests binary
Bug: v8:10674
Change-Id: I07bfe30901eb1683d2e0ee0189f73b5244884f27
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2310249
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68970}
They have been replaced with {array,struct}.new_with_rtt.
Also, rework tests that used those instructions.
Bug: v8:7748
Change-Id: I2aaccb1958bf2b8d6cad4969abc612216856393d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2307318
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68961}
... by migrating old-style code
MyObject* obj = new (zone) MyObject(...)
to the new style
MyObject* obj = zone->New<MyObject>(...)
... and prohibiting accidental use of the old-style.
Bug: v8:10689
Change-Id: Id75774ac12e3d0f95cb3a538066dffbf7815e438
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2300490
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68905}
This CL ports MarkingVerifier from blink.
The existing verifier checks only references on heap.
This new verifier checks references both on heap and on stack.
Bug: chromium:1056170
Change-Id: I083dcb0087125312cca34a2201015a9aecfe6ea4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2300484
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68891}
Adds basic framework to pipeline.cc to enable a seperate fast register
allocator for the TurboProp mid-tier. As part of this, common logic as
well as a base class for RegisterAllocationData is moved to a seperate
register-allocation.h header file. The current register allocator's
RegisterAllocationData is renamed to TopTierRegisterAllocationData, and
the former name is the new base class held in PipelineData.
BUG=v8:9684
Change-Id: I28285b7d6112505bf90e88ea3cda66d03dfabc74
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2295359
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68852}
This CL adds functionality to read the source positions directly
from the JS heap rather than from serialized data.
In order to do this, we create a PersistentHandles container in the
OptimizedCompilationInfo which gets passed onto the JSHeapBroker. This
allows us to create the handles in the main thread and pass them safely
to the background thread.
In order to read safely from the background thread, we need a LocalHeap
which blocks the GC from running and potentially moving the handles.
This LocalHeap is created only when the JSHeapBroker has finalized
serializing and destroyed when retiring it.
Bug: v8:7790
Change-Id: I19f8b08d12e5be0a3df34d6af2043310c0c7b6fe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2277802
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68836}
This is a reland of d6a14abe05
Test wasn't written with incremental/concurrent marking in mind, so
simply disabling it for this particular unittest.
Original change's description:
> [heap] Move start of incremental marking in allocation
>
> Move start of incremental marking out of
> RefillLinearAllocationAreaFromFreeList. This avoids a potential
> safepoint while holding allocation_mutex_.
>
> Bug: v8:10315
> Change-Id: Ieb60ac68f26199eea7b6b7ad6d874851382f3d69
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2287496
> Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#68751}
Bug: v8:10315
Change-Id: I2a665400d9a784b1557474a051839d5c8b45e9e2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2292241
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68818}
... by migrating old-style code
MyObject* obj = new (zone) MyObject(...)
to the new style
MyObject* obj = zone->New<MyObject>(...)
Bug: v8:10689
Change-Id: I55c686bbedfa1fd1955a5927df3f72b366312fd4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2288867
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68808}
... by migrating old-style code
MyObject* obj = new (zone) MyObject(...)
to the new style
MyObject* obj = zone->New<MyObject>(...)
Bug: v8:10689
Change-Id: I2fc4a44ea05e4d087565811f343893f0e97dc660
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2288857
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68789}
This CL removes the GetTraceDescriptor virtual call from garbage
collected mixins and replaces it with querying the object start
bitmap.
The CL also removes the mixin macros which are now no longer needed.
Bug: chromium:1056170
Change-Id: I27ed299f93025d09a3bb3f0d17b14bed3c200565
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2287508
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68787}
... by migrating old-style code
MyObject* obj = new (zone) MyObject(...)
to the new style
MyObject* obj = zone->New<MyObject>(...)
Bug: v8:10689
Change-Id: Ic7d893b8d6772bd923c37c3d1e7cff5cc6667192
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2288868
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68786}
This is a reland of bebb2bdc06
Original change's description:
> [heap] Allow LocalHeap on the main thread
>
> This changes the safepoint scope to skip LocalHeap that is active
> for the current thread to avoid deadlocking.
>
> Bug: v8:10315
> Change-Id: I45e80ae66d0dbbe768107aa9cf0603204c644d9f
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2289983
> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
> Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#68769}
Bug: v8:10315
Tbr: dinfuehr@chromium.org
Change-Id: I1974d8b6ffffbf3244e7ede2d20d9b2d623df150
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2290851
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68785}
This reverts commit bebb2bdc06.
Reason for revert: Breaks GarbageCollectionWithLocalHeap test.
https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20debug/31107
Original change's description:
> [heap] Allow LocalHeap on the main thread
>
> This changes the safepoint scope to skip LocalHeap that is active
> for the current thread to avoid deadlocking.
>
> Bug: v8:10315
> Change-Id: I45e80ae66d0dbbe768107aa9cf0603204c644d9f
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2289983
> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
> Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#68769}
TBR=ulan@chromium.org,dinfuehr@chromium.org
Change-Id: Ifba8218f9104afed3f2d92258296067f8f424062
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:10315
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2290573
Reviewed-by: Bill Budge <bbudge@chromium.org>
Commit-Queue: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68770}
This changes the safepoint scope to skip LocalHeap that is active
for the current thread to avoid deadlocking.
Bug: v8:10315
Change-Id: I45e80ae66d0dbbe768107aa9cf0603204c644d9f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2289983
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68769}
Motivation: With rtt.sub now allowed in constant expressions, we have
to generalize WasmInitExpr to be able to handle expressions with
operands. This is the second CL that prepares the ground for this
change.
Changes:
- Remove the error from read-value-type when reading a generic rtt.
- Add validation for HeapTypeImmediate in ModuleDecoder. Use it to
validate null constants immediates, which was missing. Add tests.
- Change ValueType::name to print rtt depths as integers.
- Move global initializer building in wasm-module-builder to its own
function.
Bug: v8:7748
Change-Id: Ic041e1c7d032f2a1063a21fec1bfe96cb0d8120e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2284983
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68767}
Motivation: With rtt.sub now allowed in constant expressions, we have
to generalize WasmInitExpr to be able to handle expressions with
operands. This CL prepares the ground for this change and adds no
functionality.
Changes:
- ValueType::heap_representation and HeapType::representation now
return HeapType::Representation.
- Add ValueType::is_rtt().
- WasmInitExpr:
- Make kind private. Rename val -> operator, make it private. Add
accessors.
- Rename kGlobalIndex -> kGlobalGet.
- Squash global_index and function_index into index.
- Add heap_type Immediate. Use it for RefNullConst. TypeOf in
module-decoder.cc can now fully determine the type of a
WasmInitExpr.
- Add class constructors/static method constructors for each Operator
kind.
- Delete copy constructor. WasmInitExpr will use std::unique_ptr for
its operands.
- consume_init_expr now uses a stack.
- A few minor improvements.
Bug: v8:7748
Change-Id: I3ba3ee7ac2d6bc58e887790c37110ceb80658985
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2284483
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68759}
This is needed for write-barrier and persistent-handle code that does
not otherwise get an instance of LocalHeap
Bug: v8:10315
Change-Id: I480e31f32141510f2f9e678af3449d5841e3156e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2284492
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68720}
- Adds JSVisitor that is used for unified heap marking.
- Adds JSMember as supported reference type that also encapsulates a
write barrier in future. JSMember is a replacement for
TracedReference which can be deprecated with EmbedderHeapTracer once
the library is used to handle unified heap collections.
The dispatch for v8::JSMember on cppgc::Visitor is provided through a
specialization of TraceTrait.
Bug: chromium:1056170
Change-Id: I60d976ae66db3e5fa2e690a21627bdcb8c6871af
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2284488
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68716}
In many cases, this simply requires early returning from tests which
rely on scavenger.
Bug: v8:10614
Change-Id: I5fc93b1cbc807b73bfbb113d087952e347001ddd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2270548
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Jake Hughes <jakehughes@google.com>
Cr-Commit-Position: refs/heads/master@{#68702}
This will allow it to take an OffThreadIsolate in the future, without
requiring GetIsolate on SharedFunctionInfo.
Change-Id: I7db56d5f0587585f829b26e60683c133760d8ff1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2282534
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68696}
This is the last batch of operators which used to embed the feedback
vector as a HeapConstant:
- CreateEmptyLiteralArray
- LoadGlobal
- LoadNamed
- StoreDataPropertyInLiteral
- StoreGlobal
- StoreInArrayLiteral
- StoreNamed
- StoreNamedOwn
They now take the vector as an input. In NCI mode, the vector is
loaded from the closure at the beginning of the function.
Bug: v8:8888
Change-Id: Ifd2d2a556db343512b61e099a73702822b1ba9f0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2282525
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68695}
Prior to this CL, the construct node layout was:
{target, args..., new_target}
The new layout is:
{target, new_target, args..., feedback_vector}
Having new_target at index 1 brings it closer to call node layout,
which is now identical except that it has receiver at index 1. The new
feedback vector input will be needed for NCI code.
Affected node kinds are:
- JSConstruct
- JSConstructWithArrayLike
- JSConstructWithSpread
- JSConstructForwardVarargs (just the new_target position change)
Bug: v8:8888
Change-Id: I4c68a0901d01e8862fd276c8a858799d5f4ff024
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2278475
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68692}
Split off MarkingWorklists and from Marker and introduce MarkerBase.
MarkerBase refers just to interfaces types for passing along visitors.
The concrete Marker provides the impl for these interfaces. Unified
heap marker uses different marking visitors internally but provides an
implementation for the same interface.
Change-Id: Ibc4b2c88e2e69bd303a95da7d167a701934f4a07
Bug: chromium:1056170
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2270539
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68676}
Split off MarkingState from MarkingVisitor.
With this CL the marking implementation is moved to "MarkingState"
which is the new bottleneck for marking a single object.
MarkingVisitor merely forwards to MarkingState, which knows how to set
the markbit and add the object to the worklist accordingly. This
allows to have a "UnifiedHeapMarkingVisitor" in future which can
easily reuse Marking to provide C++ marking.
Change-Id: I87ebbe37e8e8cd841e872cae9dc3490e2b55c4dd
Bug: chromium:1056170
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2270172
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68660}
