This is a reland of c927ada76c
Fix: Recalculate encoding after an allocation (that can potentially
trigger GC) in EnsureHasFullTransitionArray.
Original change's description:
> [runtime] Refactor TransitionsAccessor
>
> Problems:
> - The class uses a bare Map field, but some methods can trigger GC
> causing it to have a potential dangling pointer in case of map
> compaction.
> - Some methods invalidate the object state and should not be used again.
> - Complicate logic with a no_gc and a gc aware constructors. Some
> methods can only be called if the object is constructed with a
> particular constructor (e.g, Insert and PutPrototypeTransition).
>
> Note: Most usages of this class is done by constructing an object and
> calling a single method:
> `TransitionAccessor(...).Method(...)`
> So we can easily change them to a static method.
>
> This CL:
> 1. Adds DISALLOW_GARBAGE_COLLECTION to the class.
> 2. Makes methods that can trigger GC static.
> 3. Creates static helper functions that wrap the class in a different
> scope, since TransitionsAccessor now forces the scope to disallow gc.
> 4. Removes now unnecessary "Reload" logic.
>
> Bug: chromium:1295133, v8:12578
> Change-Id: I85484e7235fbd5e69894e26f5e1c491c6f69635e
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3450416
> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Commit-Queue: Victor Gomes <victorgomes@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#79051}
Bug: chromium:1295133, v8:12578
Change-Id: If3880c2480433b78567870c8d14508d6ad9eccbd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3460405
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Auto-Submit: Victor Gomes <victorgomes@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79069}
This reverts commit c927ada76c.
Reason for revert: GC stress failures: https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux%20-%20gc%20stress/37276/overview
Original change's description:
> [runtime] Refactor TransitionsAccessor
>
> Problems:
> - The class uses a bare Map field, but some methods can trigger GC
> causing it to have a potential dangling pointer in case of map
> compaction.
> - Some methods invalidate the object state and should not be used again.
> - Complicate logic with a no_gc and a gc aware constructors. Some
> methods can only be called if the object is constructed with a
> particular constructor (e.g, Insert and PutPrototypeTransition).
>
> Note: Most usages of this class is done by constructing an object and
> calling a single method:
> `TransitionAccessor(...).Method(...)`
> So we can easily change them to a static method.
>
> This CL:
> 1. Adds DISALLOW_GARBAGE_COLLECTION to the class.
> 2. Makes methods that can trigger GC static.
> 3. Creates static helper functions that wrap the class in a different
> scope, since TransitionsAccessor now forces the scope to disallow gc.
> 4. Removes now unnecessary "Reload" logic.
>
> Bug: chromium:1295133, v8:12578
> Change-Id: I85484e7235fbd5e69894e26f5e1c491c6f69635e
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3450416
> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Commit-Queue: Victor Gomes <victorgomes@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#79051}
Bug: chromium:1295133, v8:12578
Change-Id: Ia567cdcae73bc7fdfaf08b62eeeb899d6a933e21
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3456682
Auto-Submit: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79052}
Problems:
- The class uses a bare Map field, but some methods can trigger GC
causing it to have a potential dangling pointer in case of map
compaction.
- Some methods invalidate the object state and should not be used again.
- Complicate logic with a no_gc and a gc aware constructors. Some
methods can only be called if the object is constructed with a
particular constructor (e.g, Insert and PutPrototypeTransition).
Note: Most usages of this class is done by constructing an object and
calling a single method:
`TransitionAccessor(...).Method(...)`
So we can easily change them to a static method.
This CL:
1. Adds DISALLOW_GARBAGE_COLLECTION to the class.
2. Makes methods that can trigger GC static.
3. Creates static helper functions that wrap the class in a different
scope, since TransitionsAccessor now forces the scope to disallow gc.
4. Removes now unnecessary "Reload" logic.
Bug: chromium:1295133, v8:12578
Change-Id: I85484e7235fbd5e69894e26f5e1c491c6f69635e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3450416
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79051}
Because of LocalHeap safepoints, our existing assert scopes don't
necessarily maintain the same guarantees as desired. In particular,
DisallowHeapAllocation no longer guarantees that objects don't move.
This patch transitions DisallowHeapAllocation to
DisallowGarbageCollection, to ensure that code using this scope is
also protected against safepoints.
Change-Id: I0411425884f6849982611205fb17bb072881c722
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2540547
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71319}
... and add respective regression tests.
This CL also adds similar regression tests for TransitionArray but it
doesn't have the same issue as DescriptorArray.
Bug: chromium:1133527
Change-Id: I668a90f126d76af0a39816ce8697cb29bc65d01b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2465833
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70570}
Since we have an uninitialized TransitionArray that we want to insert
an element (map1), we can't guarantee that said element would exist at
the point of the search. Then, we search for an element guaranteed not
to be (map2) and we check that we did not find it.
If we have a data race, this would also trigger it.
Bug: v8:7790
Change-Id: Ib90044d7c0901d599aed041f608f2c0bce506d67
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2319995
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69099}
Code that is being moved primarily deal with layout of a JSObject,
accessing properties and elements, and map transitions.
NOTREECHECKS=true
NOTRY=true
Bug: v8:9247
Change-Id: Ibce5d5926ac4021c8d40c4dd109948775ce1da58
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1613994
Commit-Queue: Yang Guo <yangguo@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61638}
Removes all explicit calls to GetIsolate() in transitions.cc by passing
it through calling functions and implicit calls via the single argument
Handle constructor and handle function.
Unfortunately in the interests of making these changes vaguely
manageable, I've also pushed some new GetIsolates down into
objects-debug.cc, objects-printer.cc and objects.cc.
Bug: v8:7786
Change-Id: I1f98530dec6c004e17dc3336f3cef09fbb446bae
Reviewed-on: https://chromium-review.googlesource.com/1085451
Commit-Queue: Dan Elphick <delphick@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53518}
in preparation for caching StoreIC-Transition handlers in there.
This CL should not change behavior or performance.
The TransitionArray class no longer serves a dual purpose; it is now
simply the data structure serving that role. Further, it now supports
storing transitioning handlers in its "target" slot, which in turn have
a WeakCell pointing to the transition target (but this functionality
is not being used yet).
The interface for accessing a map's transitions, previously implemented
as a set of static functions, is now handled by the TransitionsAccessor
class. It distinguishes the following internal states:
- kPrototypeInfo: map is a prototype map, will never cache any transitions.
- kUninitialized: map can cache transitions, but doesn't have any.
- kWeakCell: map caches a single transition, stored inline. Formerly known
as "IsSimpleTransition".
- kFullTransitionArray: map uses a TransitionArray to store transitions.
- kTuple3Handler, kFixedArrayHandler: to be used in the future for caching
transitioning handlers.
Change-Id: If2aa68390981f96f317b958445a6e0b935c2a14e
Reviewed-on: https://chromium-review.googlesource.com/550118
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46981}
