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  1. 06 Jul, 2021 1 commit
  3. 30 Jun, 2021 1 commit
    • Jakob Gruber's avatar
      [compiler] Concurrent JSGlobalObjectRef::GetPropertyCell · 76b9d98f
      Jakob Gruber authored 
      .. and make JSGlobalObjectRef bg-serialized.

GetPropertyCell was implemented as:

 LookupIterator it(holder, isolate, name, LookupIterator::OWN);
 it.TryLookupCachedProperty();
 if (it.state() == LookupIterator::DATA) it.GetPropertyCell();

Due to concurrency requirements, we essentially have to reimplement
this entire path for use in a concurrent setting:

 - Reads in some cases have to use relaxed or acquire semantics.
 - The IsPendingAllocation predicate must be called on some objects
   before reading into them.
 - Repeated reads of the same field must be avoided due to the
   possibility of concurrent modifications.

This CL introduces two new methods:

ConcurrentLookupIterator::TryGetPropertyCell implements the outer
lookup logic, including the repeated lookup for accessors / cached
property names.

GlobalDictionary::TryFindPropertyCellForConcurrentLookupIterator is a
slightly modified HashTable::FindEntry which follows the above rules.

Bug: v8:7790
Change-Id: Ic9a52da766afdfedce8efcbda92876845a17eed9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2959616Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarDominik Inführ <dinfuehr@chromium.org>
Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75467}
      76b9d98f
  5. 26 Apr, 2021 1 commit
  7. 06 Apr, 2021 1 commit
    • Shu-yu Guo's avatar
      Reland^2 "[ptr-cage] Rename IsolateRoot to PtrComprCageBase" · 627b6b2f
      Shu-yu Guo authored 
      This is a reland of e28dadc2

The original failure was due to a stale Win32 bot. The reland failure
was due to idempotent task deduplication returning the exact same
failure. See crbug/1196064

Original change's description:
> [ptr-cage] Rename IsolateRoot to PtrComprCageBase
>
> Currently, IsolateRoot is both the address of the Isolate root and the
> base address of the pointer compression reservation. This CL teases the
> two uses apart by renaming IsolateRoot to PtrComprCageBase.
>
> - In addition to V8_COMPRESS_POINTERS, add a
>   V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE (vs SHARED_CAGE).
>
> - Rename GetIsolate* helpers to GetPtrComprCageBase. When
>   V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE is true, the helpers remain as
>   aliases to GetPtrComprCageBase.
>
> - Rename kPtrComprIsolateRootAlignment to kPtrComprCageBaseAlignment.
>
> Bug: v8:11460
> Change-Id: I1d715f678ce9a0b5731895612ca14f56579b1c48
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2783672
> Commit-Queue: Shu-yu Guo <syg@chromium.org>
> Auto-Submit: Shu-yu Guo <syg@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#73790}

Bug: v8:11460
No-Try: true
Tbr: ishell@chromium.org
Tbr: rmcilroy@chromium.org
Change-Id: Id69311cf3267ebe1297fff159de0be48b15b65a3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2806546Reviewed-by: 's avatarShu-yu Guo <syg@chromium.org>
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73795}
      627b6b2f
  9. 05 Apr, 2021 4 commits
    • Shu-yu Guo's avatar
      Revert "Reland "[ptr-cage] Rename IsolateRoot to PtrComprCageBase"" · 562c4251
      Shu-yu Guo authored 
      This reverts commit 15c78b45.

Reason for revert: https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Win32/32277/overview

Original change's description:
> Reland "[ptr-cage] Rename IsolateRoot to PtrComprCageBase"
>
> This is a reland of e28dadc2
>
> Relanding to see if Win32 rel failures from
> https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Win32/32275/overview
> were infra flakes. Could not repro on try bots.
>
> Original change's description:
> > [ptr-cage] Rename IsolateRoot to PtrComprCageBase
> >
> > Currently, IsolateRoot is both the address of the Isolate root and the
> > base address of the pointer compression reservation. This CL teases the
> > two uses apart by renaming IsolateRoot to PtrComprCageBase.
> >
> > - In addition to V8_COMPRESS_POINTERS, add a
> >   V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE (vs SHARED_CAGE).
> >
> > - Rename GetIsolate* helpers to GetPtrComprCageBase. When
> >   V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE is true, the helpers remain as
> >   aliases to GetPtrComprCageBase.
> >
> > - Rename kPtrComprIsolateRootAlignment to kPtrComprCageBaseAlignment.
> >
> > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2783672
> > Reviewed-by: Igor Sheludko <ishell@chromium.org>
> > Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
>
> No-Try: true
> Bug: v8:11460
> Tbr: ishell@chromium.org
> Tbr: rmcilroy@chromium.org
> Change-Id: I0a8c3a48999d6737c8c64d2c2703607f14f3fdd0
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2806169
> Reviewed-by: Shu-yu Guo <syg@chromium.org>
> Commit-Queue: Shu-yu Guo <syg@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#73792}

Bug: v8:11460
Change-Id: Ifee92d622c43a91c15f45ef94ff739237bd2024b
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2806545
Auto-Submit: Shu-yu Guo <syg@chromium.org>
Reviewed-by: 's avatarShu-yu Guo <syg@chromium.org>
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73793}
      562c4251
    • Shu-yu Guo's avatar
      Reland "[ptr-cage] Rename IsolateRoot to PtrComprCageBase" · 15c78b45
      Shu-yu Guo authored 
      This is a reland of e28dadc2

Relanding to see if Win32 rel failures from
https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Win32/32275/overview
were infra flakes. Could not repro on try bots.

Original change's description:
> [ptr-cage] Rename IsolateRoot to PtrComprCageBase
>
> Currently, IsolateRoot is both the address of the Isolate root and the
> base address of the pointer compression reservation. This CL teases the
> two uses apart by renaming IsolateRoot to PtrComprCageBase.
>
> - In addition to V8_COMPRESS_POINTERS, add a
>   V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE (vs SHARED_CAGE).
>
> - Rename GetIsolate* helpers to GetPtrComprCageBase. When
>   V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE is true, the helpers remain as
>   aliases to GetPtrComprCageBase.
>
> - Rename kPtrComprIsolateRootAlignment to kPtrComprCageBaseAlignment.
>
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2783672
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>

No-Try: true
Bug: v8:11460
Tbr: ishell@chromium.org
Tbr: rmcilroy@chromium.org
Change-Id: I0a8c3a48999d6737c8c64d2c2703607f14f3fdd0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2806169Reviewed-by: 's avatarShu-yu Guo <syg@chromium.org>
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73792}
      15c78b45
    • Francis McCabe's avatar
      Revert "[ptr-cage] Rename IsolateRoot to PtrComprCageBase" · 07a9ff4d
      Francis McCabe authored 
      This reverts commit e28dadc2.

Reason for revert: failed test262 tests;; see https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Win32/32275/steps?succeeded=true&debug=false

Original change's description:
> [ptr-cage] Rename IsolateRoot to PtrComprCageBase
>
> Currently, IsolateRoot is both the address of the Isolate root and the
> base address of the pointer compression reservation. This CL teases the
> two uses apart by renaming IsolateRoot to PtrComprCageBase.
>
> - In addition to V8_COMPRESS_POINTERS, add a
>   V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE (vs SHARED_CAGE).
>
> - Rename GetIsolate* helpers to GetPtrComprCageBase. When
>   V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE is true, the helpers remain as
>   aliases to GetPtrComprCageBase.
>
> - Rename kPtrComprIsolateRootAlignment to kPtrComprCageBaseAlignment.
>
> Bug: v8:11460
> Change-Id: I1d715f678ce9a0b5731895612ca14f56579b1c48
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2783672
> Commit-Queue: Shu-yu Guo <syg@chromium.org>
> Auto-Submit: Shu-yu Guo <syg@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#73790}

Bug: v8:11460
Change-Id: I19d0e28194fcdb28e89f129a7694ca3fe29fa17a
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2806168
Auto-Submit: Francis McCabe <fgm@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#73791}
      07a9ff4d
    • Shu-yu Guo's avatar
      [ptr-cage] Rename IsolateRoot to PtrComprCageBase · e28dadc2
      Shu-yu Guo authored 
      Currently, IsolateRoot is both the address of the Isolate root and the
base address of the pointer compression reservation. This CL teases the
two uses apart by renaming IsolateRoot to PtrComprCageBase.

- In addition to V8_COMPRESS_POINTERS, add a
  V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE (vs SHARED_CAGE).

- Rename GetIsolate* helpers to GetPtrComprCageBase. When
  V8_COMPRESS_POINTERS_IN_ISOLATE_CAGE is true, the helpers remain as
  aliases to GetPtrComprCageBase.

- Rename kPtrComprIsolateRootAlignment to kPtrComprCageBaseAlignment.

Bug: v8:11460
Change-Id: I1d715f678ce9a0b5731895612ca14f56579b1c48
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2783672
Commit-Queue: Shu-yu Guo <syg@chromium.org>
Auto-Submit: Shu-yu Guo <syg@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73790}
      e28dadc2
  11. 07 Oct, 2020 1 commit
  13. 14 Aug, 2020 1 commit
    • Leszek Swirski's avatar
      [offthread] Change OffThreadIsolate to LocalIsolate · f1589bbe
      Leszek Swirski authored 
      This patch introduces a new LocalIsolate and LocalFactory, which use
LocalHeap and replace OffThreadIsolate and OffThreadFactory. This allows
us to remove those classes, as well as the related OffThreadSpace,
OffThreadLargeObjectSpace, OffThreadHeap, and OffThreadTransferHandle.
OffThreadLogger becomes LocalLogger.

LocalHeap behaves more like Heap than OffThreadHeap did, so this allows
us to additionally remove the concept of "Finish" and "Publish" that the
OffThreadIsolate had, and allows us to internalize strings directly with
the newly-concurrent string table (where the implementation can now move
to FactoryBase).

This patch also removes the off-thread support from the deserializer
entirely, as well as removing the LocalIsolateWrapper which allowed
run-time distinction between Isolate and OffThreadIsolate. LocalHeap
doesn't support the reservation model used by the deserializer, and we
will likely move the deserializer to use LocalIsolate unconditionally
once we figure out the details of how to do this.

Bug: chromium:1011762

Change-Id: I1a1a0a72952b19a8a4c167c11a863c153a1252fc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2315990
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarAndreas Haas <ahaas@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Reviewed-by: 's avatarDominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69397}
      f1589bbe
  15. 06 Aug, 2020 1 commit
    • Leszek Swirski's avatar
      [runtime] Move string table off-heap · 1546be9c
      Leszek Swirski authored 
      Changes the isolate's string table into an off-heap structure. This
allows the string table to be resized without allocating on the V8 heap,
and potentially triggering a GC. This allows existing strings to be
inserted into the string table without requiring allocation.

This has two important benefits:

  1) It allows the deserializer to insert strings directly into the
     string table, rather than having to defer string insertion until
     deserialization completes.

  2) It simplifies the concurrent string table lookup to allow resizing
     the table inside the write lock, therefore eliminating the race
     where two concurrent lookups could both resize the table.

The off-heap string table has the following properties:

  1) The general hashmap behaviour matches the HashTable, i.e. open
     addressing, power-of-two sized, quadratic probing. This could, of
     course, now be changed.

  2) The empty and deleted sentinels are changed to Smi 0 and 1,
     respectively, to make those comparisons a bit cheaper and not
     require roots access.

  3) When the HashTable is resized, the old elements array is kept
     alive in a linked list of previous arrays, so that concurrent
     lookups don't lose the data they're accessing. This linked list
     is cleared by the GC, as then we know that all threads are in
     a safepoint.

  4) The GC treats the hash table entries as weak roots, and only walks
     them for non-live reference clearing and for evacuation.

  5) Since there is no longer a FixedArray to serialize for the startup
     snapshot, there is now a custom serialization of the string table,
     and the string table root is considered unserializable during weak
     root iteration. As a bonus, the custom serialization is more
     efficient, as it skips non-string entries.

As a drive-by, rename LookupStringExists_NoAllocate to
TryStringToIndexOrLookupExisting, to make it clearer that it returns
a non-string for the case when the string is an array index. As another
drive-by, extract StringSet into a separate header.

Bug: v8:10729
Change-Id: I9c990fb2d74d1fe222920408670974a70e969bca
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2339104
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69270}
      1546be9c
  17. 23 Jul, 2020 1 commit
  19. 22 Jul, 2020 2 commits
  21. 21 Jul, 2020 1 commit
  23. 10 Jul, 2020 2 commits
    • Leszek Swirski's avatar
      [hashtable] Allow GlobalDictionary to have holes · 82726b64
      Leszek Swirski authored 
      Rather than marking deleted GlobalDictionary entries with a "The Hole"
valued PropertyCell, we now remove those PropertyCells entirely and
use the standard HashTable deleted item marker (also the Hole).

This comes with several simplifications:

  1) We no longer need a customizable IsKey method on HastTable shapes,
     which was only used by GlobalDictionary to mark "The Hole" cells
     as not real keys,
  2) We can get rid of IsLive/IsKey from the Shape entirely, and define
     it directly in the HashTable, which will also allow us (in the
     future) to encourage caching of "undefined" and "Hole" where used
     for IsKey checks,
  3) PropertyCell invalidation doesn't necessarily have to allocate a
     new replacement cell (specifically, on deletion), nor does it have
     to deal with cells that contain the Hole,
  4) kNeedsHoleCheck is renamed to kMatchNeedsHoleCheck (to be explicit
     that this is only needed to guard IsMatch, which may do an
     indentity comparison and thus not need the HoleCheck guard). It's
     also moved out of BaseShape and into the various shapes that
     define IsMatch, to make them more explicitly think about the
     value,
  5) Modified some while loops into for loops to allow clearer use of
     "continue" on successful hole checks.

Change-Id: If591cbb6b49d59726bdc615413aba4f78fd64632
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2292230
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68807}
      82726b64
    • Leszek Swirski's avatar
      [cleanup] Move GetMap to HashTable from Shape · ae53e491
      Leszek Swirski authored 
      The map of the HashTable is more a property of the HashTable than part
of its shape, so we can move its static map getter (for construction)
to to HashTable class itself.

Change-Id: I73f4aa7260d6ce749ef51961767fd37d1ab520e4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2289782
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68805}
      ae53e491
  25. 09 Jul, 2020 1 commit
  27. 04 Mar, 2020 1 commit
  29. 03 Mar, 2020 2 commits
  31. 02 Mar, 2020 1 commit
  33. 16 Jan, 2020 1 commit
  35. 10 Jan, 2020 1 commit
  37. 27 Nov, 2019 1 commit
    • Leszek Swirski's avatar
      [isolate] Make field getters use a const Isolate* · 42a56e03
      Leszek Swirski authored 
      To indicate that the Isolate* in getters might not be a "real" isolate,
but rather a calculated one from GetIsolateForPtrCompr only used for
calculating the isolate root, make that function return a const Isolate*
and change field getters, Object::IsFoo predicates, and related
functions to all take a const Isolate* instead of an Isolate*

With this change, we can slightly more confidently use Objects that are
in OffThreadSpace, without having to worry too much about having an
Isolate* floating around that could accidentally be used.

This is a slight abuse of const semantics, but it allows implicit
conversion from Isolate* arguments to the const Isolate* parameter.

Bug: v8:7703
Bug: chromium:1011762
Change-Id: I54d4a65d2299477195f4d754cabe64ce34fdaa4c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1939455
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65199}
      42a56e03
  39. 15 Nov, 2019 1 commit
  41. 01 Nov, 2019 1 commit
  43. 24 Oct, 2019 1 commit
  45. 16 Oct, 2019 1 commit
  47. 02 Jul, 2019 1 commit
  49. 24 May, 2019 1 commit
  51. 07 May, 2019 1 commit
  53. 04 Apr, 2019 1 commit
  55. 01 Apr, 2019 1 commit
  57. 29 Mar, 2019 1 commit
  59. 25 Mar, 2019 2 commits
  61. 12 Mar, 2019 1 commit
  63. 08 Mar, 2019 1 commit
  65. 07 Mar, 2019 1 commit
    • Sigurd Schneider's avatar
      [heap] Clean-up some weak map entries in scavenger · 4e6a1a75
      Sigurd Schneider authored 
      This change enables clean-up of weak map entries in the
scavenger of the weak map is in the young generation.
With this change, the scavenger treats keys in ephemerons as
weak instead of strong, but does not implement full ephemeron
semantics: Values are treated always as strong, independently
of whether the key is live or not.

This approach ensures that no value is cleaned up accidentally.
After scavenging, all entries with dead keys are removed from
weak maps. After that, some values that are not referenced anywhere
anymore might still be in the heap, and those can be cleaned up
in the next scavenge.

What the scavenger does, amounts to one iteration of the
fixed-point algorithm required to implement ephemeron semantics.
We hope that this is a reasonable trade-off between time spent
tracing and cleaned-up entries.

This change does not affect weak maps that reside in old space.

Bug: v8:8557
Change-Id: Ic5618b3b863ad8c314c87449571150e756fecbf0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1467182
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60101}
      4e6a1a75