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  1. 26 Jul, 2018 1 commit
  3. 20 Jul, 2018 1 commit
    • Caitlin Potter's avatar
      [runtime] use new CloneObject bytecode for some ObjectLiteralSpread cases · b6f7ea58
      Caitlin Potter authored 
      As discussed in
https://docs.google.com/document/d/1sBdGe8RHgeYP850cKSSgGABTyfMdvaEWLy-vertuTCo/edit?ts=5b3ba5cc#,

this CL introduces a new bytecode (CloneObject), and a new IC type.

In this prototype implementation, the type feedback looks like the
following:

Uninitialized case:
  { uninitialized_sentinel, uninitialized_sentinel }
Monomorphic case:
  { weak 'source' map, strong 'result' map }
Polymorphic case:
  { WeakFixedArray with { weak 'source' map, strong 'result' map }, cleared value }
Megamorphic case:
  { megamorphic_sentinel, cleared_Value }

In the fast case, Object cloning is done by allocating an object with
the saved result map, and a shallow clone of the fast properties from
the source object, as well as cloned fast elements from the source object.
If at any point the fast case can't be taken, the IC transitions to the
slow case and remains there.

This prototype CL does not include any TurboFan optimization, and the
CloneObject operation is merely reduced to a stub call.

It may still be possible to get some further improvements by somehow
incorporating compile-time boilerplate elements into the cloned object,
or simplifying how the boilerplate elements are inserted into the
object.

In terms of performance, we improve the ObjectSpread score in JSTests/ObjectLiteralSpread/
by about 8x, with substantial improvements over the Babel and ObjectAssign scores.

R=gsathya@chromium.org, mvstanton@chromium.org, rmcilroy@chromium.org, neis@chromium.org, bmeurer@chromium.org
BUG=v8:7611

Change-Id: I79e1796eb77016fb4feba0e1d3bb9abb348c183e
Reviewed-on: https://chromium-review.googlesource.com/1127472
Commit-Queue: Caitlin Potter <caitp@igalia.com>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarMichael Stanton <mvstanton@chromium.org>
Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Reviewed-by: 's avatarJakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54595}
      b6f7ea58
  5. 04 Jul, 2018 1 commit
  7. 02 Jul, 2018 1 commit
  9. 15 Jun, 2018 1 commit
  11. 23 May, 2018 1 commit
  13. 18 May, 2018 1 commit
  15. 17 May, 2018 1 commit
  17. 08 May, 2018 1 commit
  19. 30 Apr, 2018 1 commit
  21. 09 Apr, 2018 1 commit
  23. 06 Apr, 2018 2 commits
    • Michael Achenbach's avatar
      Revert "[cleanup] Refactor the Factory" · 503e07c3
      Michael Achenbach authored 
      This reverts commit f9a2e24b.

Reason for revert: gc stress failures not all fixed by follow up.

Original change's description:
> [cleanup] Refactor the Factory
> 
> There is no good reason to have the meat of most objects' initialization
> logic in heap.cc, all wrapped by the CALL_HEAP_FUNCTION macro. Instead,
> this CL changes the protocol between Heap and Factory to be AllocateRaw,
> and all object initialization work after (possibly retried) successful
> raw allocation happens in the Factory.
> 
> This saves about 20KB of binary size on x64.
> 
> Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
> Change-Id: Icbfdc4266d7be8b48d2fe085f03411743dc6a0ca
> Reviewed-on: https://chromium-review.googlesource.com/959533
> Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
> Reviewed-by: Hannes Payer <hpayer@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#52416}

TBR=jkummerow@chromium.org,yangguo@chromium.org,mstarzinger@chromium.org,hpayer@chromium.org

Change-Id: Idbbc53478742f3e9525eee83342afc6aedae122f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/999414Reviewed-by: 's avatarMichael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52420}
      503e07c3
    • Jakob Kummerow's avatar
      [cleanup] Refactor the Factory · f9a2e24b
      Jakob Kummerow authored 
      There is no good reason to have the meat of most objects' initialization
logic in heap.cc, all wrapped by the CALL_HEAP_FUNCTION macro. Instead,
this CL changes the protocol between Heap and Factory to be AllocateRaw,
and all object initialization work after (possibly retried) successful
raw allocation happens in the Factory.

This saves about 20KB of binary size on x64.

Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: Icbfdc4266d7be8b48d2fe085f03411743dc6a0ca
Reviewed-on: https://chromium-review.googlesource.com/959533
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: 's avatarHannes Payer <hpayer@chromium.org>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52416}
      f9a2e24b
  25. 21 Mar, 2018 1 commit
  27. 15 Mar, 2018 1 commit
  29. 09 Mar, 2018 1 commit
    • Peter Marshall's avatar
      [memory] Save space in the FeedbackMetadata on 64 bit platforms. · 5a70a5ea
      Peter Marshall authored 
      Previously we used a FixedArray for the FeedbackMetadata, packing bits
of information into Smi fields. On 64-bit platforms, we waste at least
half of the available memory by using the Smi representation.

Given that this is just raw data (no pointers), we can just use a new
type that uses the existing packing scheme to store the data in int32
format instead.

This CL changes FeedbackMetadata to a new subclass of HeapObject. This
is to reduce the API surface exposed, in comparison to extending/using
a more general purpose data structure like ByteArray, which is also just
raw data.

FeedbackMetadata only exposes general purpose methods for accessing
slots, but hides the implementation detail of packing bits into int32
fields.

This CL also introduces a sentinal EmptyFeedbackMetadata, because there
are ~750 empty FeedbackMetadata objects when running an empty program in
V8. These are probably for builtins.

Bug: v8:7500
Change-Id: Ic85563153abbd71a22854cee8519260c32b1e9ab
Reviewed-on: https://chromium-review.googlesource.com/945730
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51842}
      5a70a5ea
  31. 05 Mar, 2018 3 commits
  33. 02 Mar, 2018 1 commit
  35. 19 Feb, 2018 1 commit
  37. 12 Feb, 2018 1 commit
    • Caitlin Potter's avatar
      [esnext] implement spec change to TaggedTemplate callsite caching · d3ca0d00
      Caitlin Potter authored 
      Implements the change outlined in https://github.com/tc39/ecma262/pull/890,
which has been ratified and pulled into the specification. In particular,
template callsite objects are no longer kept in a global, eternal Map, but
are instead associated with their callsite, which can be collected. This
prevents a memory leak incurred by TaggedTemplate calls.

Changes, summarized:

    - Remove the TemplateMap and TemplateMapShape objects, instead caching
      template objects in the feedback vector.
    - Remove the `hash` member of TemplateObjectDescriptor, and the Equals
      method (used by TemplateMap)
    - Add a new FeedbackSlotKind (kTemplateObject), which behaves similarly
      to FeedbackSlotKind::kLiteral, but prevents eval caching. This ensures
      that a new feedback vector is always created for eval() containing tagged
      templates, even when the CompilationCache is used.
    - GetTemplateObject bytecode now takes a feedback index, and only calls
      into the runtime if the feedback is Smi::kZero (uninitialized).

BUG=v8:3230, v8:2891
R=littledan@chromium.org, yangguo@chromium.org, bmeurer@chromium.org,
rmcilroy@chromium.org

Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: I7827bc148d3d93e2b056ebf63dd624da196ad423
Reviewed-on: https://chromium-review.googlesource.com/624564
Commit-Queue: Caitlin Potter <caitp@igalia.com>
Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51248}
      d3ca0d00
  39. 19 Dec, 2017 1 commit
  41. 12 Dec, 2017 1 commit
  43. 30 Nov, 2017 1 commit
  45. 23 Oct, 2017 1 commit
    • Benedikt Meurer's avatar
      [turbofan] Introduce InstanceOfIC to collect rhs feedback. · bcee1406
      Benedikt Meurer authored 
      This adds a new InstanceOfIC where the TestInstanceOf bytecode collects
constant feedback about the right-hand side of instanceof operators,
including both JSFunction and JSBoundFunction instances. TurboFan then
uses the feedback to optimize instanceof in places where the right-hand
side is not a known constant (known to TurboFan).

This addresses the odd performance cliff that we see with instanceof in
functions with multiple closures. It was discovered as one of the main
bottlenecks on the uglify-es test in the web-tooling-benchmark. The
uglify-es test (run in separation) is ~18% faster with this change.

On the micro-benchmark in the tracking bug we go from

  instanceofSingleClosure_Const: 69 ms.
  instanceofSingleClosure_Class: 246 ms.
  instanceofMultiClosure: 246 ms.
  instanceofParameter: 246 ms.

to

  instanceofSingleClosure_Const: 70 ms.
  instanceofSingleClosure_Class: 75 ms.
  instanceofMultiClosure: 76 ms.
  instanceofParameter: 73 ms.

boosting performance by roughly 3.6x and thus effectively removing the
performance cliff around instanceof.

Bug: v8:6936, v8:6971
Change-Id: Ib88dbb9eaef9cafa4a0e260fbbde73427a54046e
Reviewed-on: https://chromium-review.googlesource.com/730686
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarMichael Stanton <mvstanton@chromium.org>
Reviewed-by: 's avatarRoss McIlroy <rmcilroy@chromium.org>
Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48820}
      bcee1406
  47. 18 Oct, 2017 1 commit
  49. 26 Sep, 2017 1 commit
  51. 13 Sep, 2017 1 commit
  53. 08 Sep, 2017 1 commit
  55. 07 Sep, 2017 1 commit
  57. 01 Sep, 2017 1 commit
    • Benedikt Meurer's avatar
      [turbofan] Optimize fast enum cache driven for..in. · f1ec44e2
      Benedikt Meurer authored 
      This CL adds support to optimize for..in in fast enum-cache mode to the
same degree that it was optimized in Crankshaft, without adding the same
deoptimization loop that Crankshaft had with missing enum cache indices.
That means code like

  for (var k in o) {
    var v = o[k];
    // ...
  }

and code like

  for (var k in o) {
    if (Object.prototype.hasOwnProperty.call(o, k)) {
      var v = o[k];
      // ...
    }
  }

which follows the https://eslint.org/docs/rules/guard-for-in linter
rule, can now utilize the enum cache indices if o has only fast
properties on the receiver, which speeds up the access o[k]
significantly and reduces the pollution of the global megamorphic
stub cache.

For example the micro-benchmark in the tracking bug v8:6702 now runs
faster than ever before:

 forIn: 1516 ms.
 forInHasOwnProperty: 1674 ms.
 forInHasOwnPropertySafe: 1595 ms.
 forInSum: 2051 ms.
 forInSumSafe: 2215 ms.

Compared to numbers from V8 5.8 which is the last version running with
Crankshaft

 forIn: 1641 ms.
 forInHasOwnProperty: 1719 ms.
 forInHasOwnPropertySafe: 1802 ms.
 forInSum: 2226 ms.
 forInSumSafe: 2409 ms.

and V8 6.0 which is the current stable version with TurboFan:

 forIn: 1713 ms.
 forInHasOwnProperty: 5417 ms.
 forInHasOwnPropertySafe: 5324 ms.
 forInSum: 7556 ms.
 forInSumSafe: 11067 ms.

It also improves the throughput on the string-fasta benchmark by
around 7-10%, and there seems to be a ~5% improvement on the
Speedometer/React benchmark locally.

For this to work, the ForInPrepare bytecode was split into
ForInEnumerate and ForInPrepare, which is very similar to how it was
handled in Fullcodegen initially. In TurboFan we introduce a new
operator LoadFieldByIndex that does the dynamic property load.

This also removes the CheckMapValue operator again in favor of
just using LoadField, ReferenceEqual and CheckIf, which work
automatically with the EscapeAnalysis and the
BranchConditionElimination.

Bug: v8:6702
Change-Id: I91235413eea478ba77ace7bd14bb2f62e155dd9a
Reviewed-on: https://chromium-review.googlesource.com/645949
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47768}
      f1ec44e2
  59. 31 Aug, 2017 1 commit
  61. 28 Aug, 2017 2 commits
    • Georg Neis's avatar
      Revert "Remove obsolete kNumber binop feedback." · b4712d52
      Georg Neis authored 
      This reverts commit 1169f55b.

Reason for revert: http://crbug.com/758994

Original change's description:
> Remove obsolete kNumber binop feedback.
> 
> With the removal of Crankshaft, kNumber has become obsolete as
> BinaryOperationFeedback. Turbofan uses kNumberOrOddball.
> 
> Bug: 
> Change-Id: If577f5efcc81d7c08f43908f2764ff0ec6f8747c
> Reviewed-on: https://chromium-review.googlesource.com/628376
> Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
> Reviewed-by: Mythri Alle <mythria@chromium.org>
> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
> Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#47555}

TBR=jkummerow@chromium.org,jarin@chromium.org,neis@chromium.org,mythria@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I1b33f572f3e6865e00d2468bffcce2ea466814b3
Reviewed-on: https://chromium-review.googlesource.com/637711Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47642}
      b4712d52
    • Benedikt Meurer's avatar
      [turbofan] Optimize O.p.hasOwnProperty inside for-in. · 06753c64
      Benedikt Meurer authored 
      Optimize the common pattern

  for (var i in o) {
    if (Object.prototype.hasOwnProperty.call(o, i)) {
      // do something
    }
  }

which is part of the guard-for-in style in ESLint (see the documentation
at https://eslint.org/docs/rules/guard-for-in for details). This pattern
also shows up in React and Ember applications quite a lot (and is tested
by the appropriate Speedometer benchmarks, although not dominating those
benchmarks, since they spent a lot of time in non-TurboFan'ed code).

This improves the forInHasOwnProperty and forInHasOwnPropertySafe micro-
benchmarks in v8:6702, which look like this

  function forInHasOwnProperty(o) {
    var result = 0;
    for (var i in o) {
      if (o.hasOwnProperty(i)) {
        result += 1;
      }
    }
    return result;
  }

  function forInHasOwnPropertySafe(o) {
    var result = 0;
    for (var i in o) {
      if (Object.prototype.hasOwnProperty.call(o, i)) {
        result += 1;
      }
    }
    return result;
  }

by around 4x and allows for additional optimizations in the future, by
also elimiating the megamorphic load when accessing the enumerated
properties.

This changes the interpreter ForInNext bytecode to collect more precise
feedback about the for-in state, which now consists of three individual
states: UNINITIALIZED, MEGAMORPHIC and GENERIC. The MEGAMORPHIC state
means that the ForInNext has only seen objects with a usable enum cache
thus far, whereas GENERIC means that we have seen some slow-mode for..in
objects as well.

R=jarin@chromium.org

Bug: v8:6702
Change-Id: Ibcd75ea9b58c3b4f9219f11bc37eb04a2b985604
Reviewed-on: https://chromium-review.googlesource.com/636964
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47632}
      06753c64
  63. 23 Aug, 2017 1 commit
  65. 11 Aug, 2017 1 commit
    • Benedikt Meurer's avatar
      [turbofan] Collect and use SignedSmall input feedback for Divide. · 622852e5
      Benedikt Meurer authored 
      For Divide operations like

  r = a / b

where r has only truncated uses (i.e. only used in bitwise operations),
we used to generate a Float64Div unless we statically knew something
about a and b, even if a and b have always been integers so far.
Crankshaft was able to generate an integer division here, because
Fullcodegen collected feedback independently for inputs and outputs of
binary operations.

This adds new BinaryOperationFeedback::kSignedSmallInputs, which is used
specifically for Divide to state that we have seen only SignedSmall
inputs thus far, but the outputs weren't always in the SignedSmall
range.

The issue was discovered in a WebGL Triangulation library and reported
via https://twitter.com/mourner/status/895708603117518848 after Node
8.3.0 was released with I+TF.

R=jarin@chromium.org

Bug: v8:6698
Change-Id: I830e421a3bf91fc8fa3665cbb706bc13675a6d2b
Reviewed-on: https://chromium-review.googlesource.com/612063
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarJaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47302}
      622852e5
  67. 07 Aug, 2017 3 commits
    • Benedikt Meurer's avatar
      [ic] Properly integrate the CallIC into Ignition. · ee350c31
      Benedikt Meurer authored 
      Drop the deprecated CallConstructStub and remove the use of CallICStub
from fullcodegen, since that feedback is unused completely every since
Crankshaft got removed, thus we can safely unlink all the CallIC stuff
from fullcodegen nowadays, and completely nuke the CallICStub and the
CallICTrampolineStub now (we can also transitively nuke the unused
CreateAllocationSiteStub and CreateWeakCellStub).

Instead the CallIC logic is integrated into Ignition now, and part of
the bytecode handlers for [[Call]] and [[Construct]]. There's still some
follow-up cleanup with the way the Array constructor feedback is
integrated, but that's way easier now.

Bug: v8:5517, v8:6399, v8:6409, v8:6679
Change-Id: I0a6c6046faceca9b1606577bc9e63d9295e44619
Reviewed-on: https://chromium-review.googlesource.com/603609
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarMichael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47196}
      ee350c31
    • Michael Achenbach's avatar
      Revert "[ic] Properly integrate the CallIC into Ignition." · 018128a4
      Michael Achenbach authored 
      This reverts commit 6c541561.

Reason for revert:
https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20nosnap/builds/17240

Original change's description:
> [ic] Properly integrate the CallIC into Ignition.
> 
> Drop the deprecated CallConstructStub and remove the use of CallICStub
> from fullcodegen, since that feedback is unused completely every since
> Crankshaft got removed, thus we can safely unlink all the CallIC stuff
> from fullcodegen nowadays, and completely nuke the CallICStub and the
> CallICTrampolineStub now (we can also transitively nuke the unused
> CreateAllocationSiteStub and CreateWeakCellStub).
> 
> Instead the CallIC logic is integrated into Ignition now, and part of
> the bytecode handlers for [[Call]] and [[Construct]]. There's still some
> follow-up cleanup with the way the Array constructor feedback is
> integrated, but that's way easier now.
> 
> Bug: v8:5517, v8:6399, v8:6409, v8:6679
> Change-Id: Ia0efc6145ee64633757a6c3fd1879d4906ea2835
> Reviewed-on: https://chromium-review.googlesource.com/602134
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#47192}

TBR=rmcilroy@chromium.org,yangguo@chromium.org,bmeurer@chromium.org

Change-Id: I416ce6646f62ceb4127b3acee43912ee0d701c23
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:5517, v8:6399, v8:6409, v8:6679
Reviewed-on: https://chromium-review.googlesource.com/603647Reviewed-by: 's avatarMichael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47193}
      018128a4
    • Benedikt Meurer's avatar
      [ic] Properly integrate the CallIC into Ignition. · 6c541561
      Benedikt Meurer authored 
      Drop the deprecated CallConstructStub and remove the use of CallICStub
from fullcodegen, since that feedback is unused completely every since
Crankshaft got removed, thus we can safely unlink all the CallIC stuff
from fullcodegen nowadays, and completely nuke the CallICStub and the
CallICTrampolineStub now (we can also transitively nuke the unused
CreateAllocationSiteStub and CreateWeakCellStub).

Instead the CallIC logic is integrated into Ignition now, and part of
the bytecode handlers for [[Call]] and [[Construct]]. There's still some
follow-up cleanup with the way the Array constructor feedback is
integrated, but that's way easier now.

Bug: v8:5517, v8:6399, v8:6409, v8:6679
Change-Id: Ia0efc6145ee64633757a6c3fd1879d4906ea2835
Reviewed-on: https://chromium-review.googlesource.com/602134
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47192}
      6c541561