Commit Graph

346 Commits

Author SHA1 Message Date
Ulan Degenbaev
252e8a1c2d [heap-profiler] Merge embedder nodes and V8 wrapper nodes.
Each DOM node has the corresponding V8 wrapper object. This leads to
apparent duplication in the heap snapshot and may confuse the users.

This patch allows the embedder to specify V8 wrapper for each embedder
node. In the heap snapshot the wrapper node will be merged into the
embedder node. The resulting node will have the same properties as
the embedder node. If the wrapper node name has a tag, then the tag
is also added to the merged node.

Bug: chromium:811925

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I2492f5b28163a78aee707b9ced1b09ac4b203e3f
Reviewed-on: https://chromium-review.googlesource.com/919482
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51394}
2018-02-20 15:04:48 +00:00
Ulan Degenbaev
466d157cb7 [api] Add API for annotating retainer of a strong global handle.
This adds PersistentBase::AnnotateStrongRetainer(const char*) function.

The annotation is used by the heap snapshot generator to show the edges
from the (Global handles) root to the global handles.

Bug: chromium:811842
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I1a9e3e53a53aeaf2b590709fab8dd4ecf7e8f252
Reviewed-on: https://chromium-review.googlesource.com/916788
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51358}
2018-02-19 11:42:03 +00:00
Adam Klein
3916401e4b Revert "[builtins] Mega-revert to address the Dev blocker in crbug.com/808911."
This reverts commit 14108f4c2e.

Reason for revert: Not the culprit for Canary microtask crashes

Original change's description:
> [builtins] Mega-revert to address the Dev blocker in crbug.com/808911.
> 
> - Revert "[builtins] Save one word in contexts for Promise.all."
>   This reverts commit 7632da067b.
> - Revert "[builtins] Also use the Promise#then protector for Promise#finally()."
>   This reverts commit d4f072ced3.
> - Revert "[builtins] Don't mess with entered context for MicrotaskCallbacks."
>   This reverts commit 6703dacdd6.
> - Revert "[debugger] Properly deal with settled promises in catch prediction."
>   This reverts commit 40dd065823.
> - Revert "[builtins] Widen the fast-path for Promise builtins."
>   This reverts commit db0556b7e8.
> - Revert "[builtins] Unify PerformPromiseThen and optimize it with TurboFan."
>   This reverts commit a582199c5e.
> - Revert "[builtins] Remove obsolete PromiseBuiltinsAssembler::AppendPromiseCallback."
>   This reverts commit 6bf8885290.
> - Revert "[builtins] Turn NewPromiseCapability into a proper builtin."
>   This reverts commit 313b490ddd.
> - Revert "[builtins] Inline InternalPromiseThen into it's only caller"
>   This reverts commit f7bd6a2fd6.
> - Revert "[builtins] Implement Promise#catch by really calling into Promise#then."
>   This reverts commit b23b098fa0.
> - Revert "[promise] Remove incorrect fast path"
>   This reverts commit 0f6eafe855.
> - Revert "[builtins] Squeeze JSPromise::result and JSPromise::reactions into a single field."
>   This reverts commit 8a677a2831.
> - Revert "[builtins] Refactor promises to reduce GC overhead."
>   This reverts commit 8e7737cb58.
> 
> Tbr: hpayer@chromium.org
> Bug: chromium:800651, chromium:808911, v8:5691, v8:7253
> Change-Id: I8c8ea5ed32ed62f6cd8b0d027a3707ddd891e5f1
> Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
> Reviewed-on: https://chromium-review.googlesource.com/906991
> Commit-Queue: Yang Guo <yangguo@chromium.org>
> Commit-Queue: Adam Klein <adamk@chromium.org>
> Reviewed-by: Adam Klein <adamk@chromium.org>
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#51158}

Change-Id: I09d958cbebd635a325809072a290f2f53df8c5d4
Tbr: adamk@chromium.org,yangguo@chromium.org,bmeurer@chromium.org
Bug: chromium:800651, chromium:808911, v8:5691, v8:7253
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/908988
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51181}
2018-02-08 17:25:13 +00:00
Benedikt Meurer
14108f4c2e [builtins] Mega-revert to address the Dev blocker in crbug.com/808911.
- Revert "[builtins] Save one word in contexts for Promise.all."
  This reverts commit 7632da067b.
- Revert "[builtins] Also use the Promise#then protector for Promise#finally()."
  This reverts commit d4f072ced3.
- Revert "[builtins] Don't mess with entered context for MicrotaskCallbacks."
  This reverts commit 6703dacdd6.
- Revert "[debugger] Properly deal with settled promises in catch prediction."
  This reverts commit 40dd065823.
- Revert "[builtins] Widen the fast-path for Promise builtins."
  This reverts commit db0556b7e8.
- Revert "[builtins] Unify PerformPromiseThen and optimize it with TurboFan."
  This reverts commit a582199c5e.
- Revert "[builtins] Remove obsolete PromiseBuiltinsAssembler::AppendPromiseCallback."
  This reverts commit 6bf8885290.
- Revert "[builtins] Turn NewPromiseCapability into a proper builtin."
  This reverts commit 313b490ddd.
- Revert "[builtins] Inline InternalPromiseThen into it's only caller"
  This reverts commit f7bd6a2fd6.
- Revert "[builtins] Implement Promise#catch by really calling into Promise#then."
  This reverts commit b23b098fa0.
- Revert "[promise] Remove incorrect fast path"
  This reverts commit 0f6eafe855.
- Revert "[builtins] Squeeze JSPromise::result and JSPromise::reactions into a single field."
  This reverts commit 8a677a2831.
- Revert "[builtins] Refactor promises to reduce GC overhead."
  This reverts commit 8e7737cb58.

Tbr: hpayer@chromium.org
Bug: chromium:800651, chromium:808911, v8:5691, v8:7253
Change-Id: I8c8ea5ed32ed62f6cd8b0d027a3707ddd891e5f1
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/906991
Commit-Queue: Yang Guo <yangguo@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51158}
2018-02-07 19:46:59 +00:00
Ulan Degenbaev
b049ac84f2 Add a flag for EmbedderGraph in heap snapshot.
The flag is enabled by default and provides a quick way to switch
between the old RetainerInfo and the new EmbedderGraph snapshoting
in local testing.

Bug: chromium:749490
Change-Id: I36406597a289090879cfa5051037c8cf35988e59
Reviewed-on: https://chromium-review.googlesource.com/897532
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51045}
2018-02-01 17:42:30 +00:00
Ulan Degenbaev
239dd8124b New API for capturing embedder object graph in heap snapshot.
That patch introduces EmbedderGraph interface that embedders can use to
represent C++ objects that retain or are retained by V8 JS objects.

The heap snapshot generator adds nodes and edges of the EmbedderGraph to
the heap snapshot, allowing arbitrarily complex retaining paths that
cross V8/Embedder boundary.

The new functionality is enabled only if the embedder sets the
BuildEmbedderGraph callback.


Bug: chromium:749490

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I10a1fa000d6d4ba47fc19d84c7cfc2c619d496fc
Reviewed-on: https://chromium-review.googlesource.com/890521
Reviewed-by: Alexei Filippov <alph@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51016}
2018-02-01 08:05:14 +00:00
Benedikt Meurer
8a677a2831 [builtins] Squeeze JSPromise::result and JSPromise::reactions into a single field.
A given JSPromise can either be in pending state, and accumulates
reactions, or in settled state, where all reactions are scheduled
as microtasks, and it carries a result. So we can use a single field
on the JSPromise instance to hold both the result and the reactions
and that field is interpreted differently depending on the status of
the JSPromise.

Bug: v8:7253
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I19a7d499c88f452f0d35979ab95deb110021cde9
Reviewed-on: https://chromium-review.googlesource.com/895528
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51004}
2018-01-31 17:08:46 +00:00
Benedikt Meurer
8e7737cb58 [builtins] Refactor promises to reduce GC overhead.
This implements the ideas outlined in the section "Microtask queue"
of the exploration document "Promise and async/await performance" (at
https://goo.gl/WHRar2), except that the microtask queue stays a linear
FixedArray for now, to avoid running into trouble with the parallel
scavenger. This way we can already save a significant amount of
allocations, thereby reducing the GC frequency quite a bit.

All items on the microtask queue are now proper structs that subclass
Microtask, i.e. we also wrap JSFunction and MicrotaskCallback jobs
into structs. We also consistently remember the context for every
microtask (except for MicrotaskCallback where we don't have a
context), and execute it later in exactly that context (as required
by the spec anyways for the Promise related jobs). Particularly
interesting is the PromiseReactionJobTask and its subclasses, since
they are designed to have the same size as the PromiseReaction. When
we resolve a JSPromise we just take the existing PromiseReaction
instances and morph them into PromiseFulfillReactionJobTask or
PromiseRejectReactionJobTask (depending whether you "Fulfill" or
"Reject"). That way the JSPromise class is now only 6 words instead
of 10 words.

Also the PromiseReaction and the reaction tasks can either carry a
JSPromise (for the fast native case) or a PromiseCapability (for the
generic case), which means we don't always pay the overhead of having
to also remember the "deferred resolve" and "deferred reject" handlers
that are only relevant for the generic case anyways.

It also fixes a spec violation where we called "then" before we actually
enqueued the PromiseResolveThenableJob, which is observably wrong.
Calling it later has the advantage that it should be fairly
straight-forward now to completely avoid it for native Promise
instances.

This seems to save around 10-20% on the various Promise benchmarks and
micro-benchmarks. We expect to gain even more as we're now able to
inline various operations into TurboFan optimized code easily.

Bug: v8:7253
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I893d24ca5bb046974b4f5826a8f6dd22f1210b6a
Reviewed-on: https://chromium-review.googlesource.com/892819
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50980}
2018-01-31 10:05:39 +00:00
Ali Ijaz Sheikh
a2a5a49525 [profiler] specially mark allocations during deopt
Deoptimization may materialize values on the heap, which may get sampled
by the heap profiler. Such samples have imprecise stack. Indicate this.

BUG=v8:7314

Change-Id: I21ab079c36fc0492b05b546cc1d6a8e6c042aeb8
Reviewed-on: https://chromium-review.googlesource.com/877119
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50775}
2018-01-22 20:05:07 +00:00
Anna Henningsen
55b48798eb [heap-profiler] remove bogus DCHECK
A map’s `constructor_or_backpointer` can be any kind of value,
because `fn.prototype = foo` sets that field to `foo` if the
latter is not a `JSReceiver`; so the `DCHECK` that is being
removed here was invalid.

Refs: https://github.com/nodejs/node/issues/18223
Bug: node:18223
Change-Id: Ia6449c07bb724e515d73b162369ab36ab1d89c6b
Reviewed-on: https://chromium-review.googlesource.com/874472
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50735}
2018-01-19 23:46:51 +00:00
Clemens Hammacher
2203a37c5d Replace CHECK(false) by UNREACHABLE()
... or sometimes by FATAL(...) to give a better error message.
The benefit of UNREACHABLE() over CHECK(false) is that the compiler
knows that this macro will never return, hence we can omit the return
of a dummy value afterwards.

R=neis@chromium.org

Change-Id: I14e6a4f1d75f1338f481bd1520d841fd383d6202
Reviewed-on: https://chromium-review.googlesource.com/832431
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50214}
2017-12-19 18:58:07 +00:00
Mathias Bynens
822be9b238 Normalize casing of hexadecimal digits
This patch normalizes the casing of hexadecimal digits in escape
sequences of the form `\xNN` and integer literals of the form
`0xNNNN`.

Previously, the V8 code base used an inconsistent mixture of uppercase
and lowercase.

Google’s C++ style guide uses uppercase in its examples:
https://google.github.io/styleguide/cppguide.html#Non-ASCII_Characters

Moreover, uppercase letters more clearly stand out from the lowercase
`x` (or `u`) characters at the start, as well as lowercase letters
elsewhere in strings.

BUG=v8:7109
TBR=marja@chromium.org,titzer@chromium.org,mtrofin@chromium.org,mstarzinger@chromium.org,rossberg@chromium.org,yangguo@chromium.org,mlippautz@chromium.org
NOPRESUBMIT=true

Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I790e21c25d96ad5d95c8229724eb45d2aa9e22d6
Reviewed-on: https://chromium-review.googlesource.com/804294
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49810}
2017-12-02 01:24:40 +00:00
Ali Ijaz Sheikh
6331766224 [heap] Add missing steps for Add/Remove observers (reland^2)
(Previously landed as #48513 / e770879eee)
(Previously landed as #48606 / d0e3fb4f2e)

CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel;master.tryserver.chromium.android:android_optional_gpu_tests_rel

Bug: 
Change-Id: I302fb52fb47b6c9d59dd2b28eb9923c37881c15b
Reviewed-on: https://chromium-review.googlesource.com/794857
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Cr-Commit-Position: refs/heads/master@{#49763}
2017-11-30 16:35:14 +00:00
Michael Starzinger
d1193e3c6c Adapt heap profiler test to changed GC timing.
R=machenbach@chromium.org
BUG=v8:6792
NOTREECHECKS=true
NOTRY=true

Change-Id: I878b11c6bddeca59ff49bfa88031a4ce15507e04
Reviewed-on: https://chromium-review.googlesource.com/759039
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49261}
2017-11-09 10:55:05 +00:00
Benedikt Meurer
781f7685b6 Reintroduce compile-time --string-slices flag.
This partially reverts commit aaebbbaa59,
which removed the --string-slices flag. We reintroduce the flag as a
build time flag for an experiment to gather information of how much
SliceStrings help with throughput and effective memory use.

Bug: v8:7025
Change-Id: I529da91bb7501fe93d83891abf560710f3ecb9d0
Reviewed-on: https://chromium-review.googlesource.com/750681
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49068}
2017-11-02 06:59:14 +00:00
Alexei Filippov
e8636cd75b Reland "[heap-profiler] Do not treat WeakMap values as weak."
This is a reland of c34042cc64
Original change's description:
> [heap-profiler] Do not treat WeakMap values as weak.
> 
> For the WeakHashTable objects only mark keys as weak while leaving values as strong references.
> 
> BUG=chomium:773722
> 
> Change-Id: Iabd5ba293d05fe68a2af6503fcdd711ecc182482
> Reviewed-on: https://chromium-review.googlesource.com/730771
> Commit-Queue: Alexei Filippov <alph@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48985}

TBR=ulan@chromium.org

Bug: chomium:773722
Change-Id: Icede16fde528d147cde5c3f6c72f2029876b099f
Reviewed-on: https://chromium-review.googlesource.com/740722
Reviewed-by: Alexei Filippov <alph@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48987}
2017-10-26 23:04:31 +00:00
Alexei Filippov
f5a3b75f9c Revert "[heap-profiler] Do not treat WeakMap values as weak."
This reverts commit c34042cc64.

Reason for revert: Wrong table type was used

Original change's description:
> [heap-profiler] Do not treat WeakMap values as weak.
> 
> For the WeakHashTable objects only mark keys as weak while leaving values as strong references.
> 
> BUG=chomium:773722
> 
> Change-Id: Iabd5ba293d05fe68a2af6503fcdd711ecc182482
> Reviewed-on: https://chromium-review.googlesource.com/730771
> Commit-Queue: Alexei Filippov <alph@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48985}

TBR=ulan@chromium.org,alph@chromium.org,mlippautz@chromium.org

Change-Id: Ia2ddef5b2422d4cbb8c4710e24ed0885a9a5b284
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chomium:773722
Reviewed-on: https://chromium-review.googlesource.com/740721
Reviewed-by: Alexei Filippov <alph@chromium.org>
Commit-Queue: Alexei Filippov <alph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48986}
2017-10-26 22:20:44 +00:00
Alexei Filippov
c34042cc64 [heap-profiler] Do not treat WeakMap values as weak.
For the WeakHashTable objects only mark keys as weak while leaving values as strong references.

BUG=chomium:773722

Change-Id: Iabd5ba293d05fe68a2af6503fcdd711ecc182482
Reviewed-on: https://chromium-review.googlesource.com/730771
Commit-Queue: Alexei Filippov <alph@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48985}
2017-10-26 20:58:49 +00:00
Clemens Hammacher
5f6510825a [cleanup] Fix remaining (D)CHECK macro usages
This CL fixes all occurences that don't require special OWNER reviews,
or can be reviewed by Michi.

After this one, we should be able to reenable the readability/check
cpplint check.

R=mstarzinger@chromium.org

Bug: v8:6837, v8:6921
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng;master.tryserver.v8:v8_linux_noi18n_rel_ng
Change-Id: Ic81d68d5534eaa795b7197fed5c41ed158361d62
Reviewed-on: https://chromium-review.googlesource.com/721120
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48670}
2017-10-18 10:12:31 +00:00
Michael Achenbach
fb71512528 Revert "Reland: [heap] Add missing steps for Add/Remove observers"
This reverts commit d0e3fb4f2e.

Reason for revert: Failures on all GPU bots:
https://build.chromium.org/p/client.v8.fyi/builders/Win%20Release%20%28NVIDIA%29/builds/3171
https://build.chromium.org/p/client.v8.fyi/builders/Linux%20Release%20%28NVIDIA%29/builds/3730

Original change's description:
> Reland: [heap] Add missing steps for Add/Remove observers
> 
> This is a reland of https://chromium-review.googlesource.com/c/v8/v8/+/715118.
> The UI doesn't allow me to reland this automatically due to merge conflicts
> so I ended up doing this manually.
> 
> Change-Id: Ic013b61f459cb1e91e24203fb31ae7c14f3754f8
> Reviewed-on: https://chromium-review.googlesource.com/720136
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
> Cr-Commit-Position: refs/heads/master@{#48606}

TBR=ulan@chromium.org,mlippautz@chromium.org,ofrobots@google.com

Change-Id: I80f63ac0cc54471b3ecaa7b6d85b1805ea599dd4
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/721440
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48614}
2017-10-16 19:38:49 +00:00
Ali Ijaz Sheikh
d0e3fb4f2e Reland: [heap] Add missing steps for Add/Remove observers
This is a reland of https://chromium-review.googlesource.com/c/v8/v8/+/715118.
The UI doesn't allow me to reland this automatically due to merge conflicts
so I ended up doing this manually.

Change-Id: Ic013b61f459cb1e91e24203fb31ae7c14f3754f8
Reviewed-on: https://chromium-review.googlesource.com/720136
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Cr-Commit-Position: refs/heads/master@{#48606}
2017-10-16 16:40:39 +00:00
Mathias Bynens
62f929ff4c Use nullptr instead of NULL where possible
New code should use nullptr instead of NULL.

This patch updates existing use of NULL to nullptr where applicable,
making the code base more consistent.

BUG=v8:6928,v8:6921

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng;master.tryserver.v8:v8_linux_noi18n_rel_ng
Change-Id: I4687f5b96fcfd88b41fa970a2b937b4f6538777c
Reviewed-on: https://chromium-review.googlesource.com/718338
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48557}
2017-10-13 17:21:49 +00:00
Ali Ijaz Sheikh
1cedda2510 Revert "[heap] Add missing steps for Add/Remove observers"
This reverts commit e770879eee.

Reason for revert: broke on this build: https://build.chromium.org/p/client.v8/builders/V8%20Mac%20-%20debug/builds/16703

Original change's description:
> [heap] Add missing steps for Add/Remove observers
> 
> Change-Id: I9935ff4debc623af674e606c006085258b685ced
> Reviewed-on: https://chromium-review.googlesource.com/715118
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
> Cr-Commit-Position: refs/heads/master@{#48513}

TBR=ulan@chromium.org,mlippautz@chromium.org,ofrobots@google.com

Change-Id: Idc53870cbcb692e79764dfe0984ff765ed2458f3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/717318
Reviewed-by: Ali Ijaz Sheikh <ofrobots@google.com>
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Cr-Commit-Position: refs/heads/master@{#48515}
2017-10-12 22:22:16 +00:00
Ali Ijaz Sheikh
e770879eee [heap] Add missing steps for Add/Remove observers
Change-Id: I9935ff4debc623af674e606c006085258b685ced
Reviewed-on: https://chromium-review.googlesource.com/715118
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Cr-Commit-Position: refs/heads/master@{#48513}
2017-10-12 21:37:33 +00:00
Ali Ijaz Sheikh
52e8d0ab40 Reland "Reland "[profiler] proper observation of old space inline allocations""
This is a reland of ec952aaa68.

Included is a fix that ensures that top_on_previous_step_ is cleared when we
release a page.

Original change's description:
> Reland "[profiler] proper observation of old space inline allocations"
>
> This is a reland of 672a41c3ca
> Original change's description:
> > [profiler] proper observation of old space inline allocations
> >
> > Bug: chromium:633920
> > Change-Id: I9a2f4a89f6b9c0f63cb3b166b06a88a12f0a203c
> > Reviewed-on: https://chromium-review.googlesource.com/631696
> > Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48043}
>
> Bug: chromium:633920
> Change-Id: I6fe743d31b8ff26f3858488d4c014c62d3c85add
> Reviewed-on: https://chromium-review.googlesource.com/671127
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
> Cr-Commit-Position: refs/heads/master@{#48085}

Bug: chromium:633920
Change-Id: I8a0dcc4eaffc1f1d3ac5b3f8d344001cdae36606
Reviewed-on: https://chromium-review.googlesource.com/677407
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Cr-Commit-Position: refs/heads/master@{#48141}
2017-09-25 15:13:01 +00:00
Ulan Degenbaev
f16b561bee Revert "Reland "[profiler] proper observation of old space inline allocations""
This reverts commit ec952aaa68.

Reason for revert: https://bugs.chromium.org/p/chromium/issues/detail?id=767144

Original change's description:
> Reland "[profiler] proper observation of old space inline allocations"
> 
> This is a reland of 672a41c3ca
> Original change's description:
> > [profiler] proper observation of old space inline allocations
> > 
> > Bug: chromium:633920
> > Change-Id: I9a2f4a89f6b9c0f63cb3b166b06a88a12f0a203c
> > Reviewed-on: https://chromium-review.googlesource.com/631696
> > Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#48043}
> 
> Bug: chromium:633920
> Change-Id: I6fe743d31b8ff26f3858488d4c014c62d3c85add
> Reviewed-on: https://chromium-review.googlesource.com/671127
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
> Cr-Commit-Position: refs/heads/master@{#48085}

TBR=ulan@chromium.org,mlippautz@chromium.org,ofrobots@google.com

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

Bug: chromium:633920
Change-Id: I576cdab4a03f9fe057ebe1bf7da9dfe3c7bf62cd
Reviewed-on: https://chromium-review.googlesource.com/676683
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48098}
2017-09-21 04:19:29 +00:00
Ali Ijaz Sheikh
ec952aaa68 Reland "[profiler] proper observation of old space inline allocations"
This is a reland of 672a41c3ca
Original change's description:
> [profiler] proper observation of old space inline allocations
> 
> Bug: chromium:633920
> Change-Id: I9a2f4a89f6b9c0f63cb3b166b06a88a12f0a203c
> Reviewed-on: https://chromium-review.googlesource.com/631696
> Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48043}

Bug: chromium:633920
Change-Id: I6fe743d31b8ff26f3858488d4c014c62d3c85add
Reviewed-on: https://chromium-review.googlesource.com/671127
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Cr-Commit-Position: refs/heads/master@{#48085}
2017-09-20 01:28:55 +00:00
Ali Ijaz Sheikh
258f270f15 Revert "[profiler] proper observation of old space inline allocations"
This reverts commit 672a41c3ca.

Reason for revert: Linux64 TSAN bot failures

Original change's description:
> [profiler] proper observation of old space inline allocations
> 
> Bug: chromium:633920
> Change-Id: I9a2f4a89f6b9c0f63cb3b166b06a88a12f0a203c
> Reviewed-on: https://chromium-review.googlesource.com/631696
> Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#48043}

TBR=ulan@chromium.org,mlippautz@chromium.org,ofrobots@google.com

Change-Id: Ib71baf69b29b067fa0ba76027170054b8faa78d3
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:633920
Reviewed-on: https://chromium-review.googlesource.com/669559
Reviewed-by: Ali Ijaz Sheikh <ofrobots@google.com>
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Cr-Commit-Position: refs/heads/master@{#48052}
2017-09-15 20:38:18 +00:00
Ali Ijaz Sheikh
672a41c3ca [profiler] proper observation of old space inline allocations
Bug: chromium:633920
Change-Id: I9a2f4a89f6b9c0f63cb3b166b06a88a12f0a203c
Reviewed-on: https://chromium-review.googlesource.com/631696
Commit-Queue: Ali Ijaz Sheikh <ofrobots@google.com>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48043}
2017-09-15 14:11:46 +00:00
Peter Marshall
ab43c76dde [cleanup] Replace List with std::vector in uri, debug, and others.
Bug: v8:6333
Change-Id: Ibc704172ebc796977b8d8cfae6976666d186f12c
Reviewed-on: https://chromium-review.googlesource.com/652450
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47890}
2017-09-07 15:04:31 +00:00
Peter Marshall
abaece06d2 [cleanup] Replace List with std::vector in cctests and d8.
Bug: v8:6333
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: Iabaef0e63c81db503eb2f19bf63a1f77313f2a5a
Reviewed-on: https://chromium-review.googlesource.com/635591
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47681}
2017-08-29 13:29:26 +00:00
Mateusz Czeladka
fe598532ec Pass Isolate pointer to String::Utf8Value/Value constructors
As part of J2V8 development (https://github.com/eclipsesource/J2V8),
we realized that we had a subtle bug in how Isolate scope was created
and it's lifetime managed, see:
https://github.com/eclipsesource/J2V8/issues/313.

Mentioned above bug was fixed, however, what we also noticed is that
V8 API has been constantly and slowly moving to such an API, in which
one has to pass Isolate explicitly to methods and/or constructors. We
found two more places that might have been overlooked. This contribution
adds passing of Isolate pointer explicitly to constructors of
String::Utf8Value and String::Value classes.

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng;master.tryserver.v8:v8_linux_noi18n_rel_ng
Change-Id: I61984285f152aba5ca922100cf3df913a9cb2cea
Reviewed-on: https://chromium-review.googlesource.com/593309
Commit-Queue: Adam Klein <adamk@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47656}
2017-08-28 18:17:08 +00:00
Alexei Filippov
9d0438ba56 [heap-profiler] Instrument JSPromise
Change-Id: I0c46b8b86a6ea33e4f48d498e1521fac54e3305e
Reviewed-on: https://chromium-review.googlesource.com/578728
Commit-Queue: Alexei Filippov <alph@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46802}
2017-07-20 18:14:25 +00:00
Mythri
3e47cb87d6 [Turbofan] Use bytecode size for inlining heuristics.
Inlining heuristics in Turbofan used ast node count. Bytecode size
is a better approximation of the size of the graph than the
ast node count. This cl changes the heuristics to use the bytecode
size instead. Also removing the ast_node_count filed in the shared
function info. It was used only for the inlining heuristics.

Also removed the max_inlined_source_size flag which is no longer used.

Bug: 
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I8a2d2509c8e8d2779b33b817bb217de203d54ec3
Reviewed-on: https://chromium-review.googlesource.com/570055
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46771}
2017-07-19 17:01:55 +00:00
ulan
75e679113b [heap] Add --stress-incremental-marking flag.
BUG=

Review-Url: https://codereview.chromium.org/2900603004
Cr-Commit-Position: refs/heads/master@{#45553}
2017-05-29 11:06:13 +00:00
Mythri
96b0928939 Remove crankshaft flag.
Crankshaft flag and opt flag mostly serve the same purpose. Using 
crankshaft to mean use optimizing compiler is a bit confusing.
This cl: https://chromium-review.googlesource.com/c/490206/ fixes 
the tests to use opt instead of crankshaft flag.

One difference between --no-crankshaft and --no-opt would be that 
--no-opt would mean no optimizations at all where as with --no-crankshaft
would mean we can force optimizations using %OptimizeFunctionOnNextCall.

Bug: v8:6325
Change-Id: If17393ac5b6af4ea6e9a98e092f0261c2e0899c5
Reviewed-on: https://chromium-review.googlesource.com/490307
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45298}
2017-05-15 12:34:20 +00:00
Adam Klein
b3887f8a2c [cctest] Simplify the majority of callers of CcTest::CollectAllGarbage
Most callers passed kFinalizeIncrementalMarkingMask, so use that as
a default argument (not using default argument syntax to avoid including
heap.h in cctest.h).

Change-Id: I904f1eb3a0f5fdbe63eab16f6a6f01d04618645d
Reviewed-on: https://chromium-review.googlesource.com/488104
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44950}
2017-04-27 17:20:54 +00:00
Toon Verwaest
0a8de761ff Remove unused Box type
BUG=

Change-Id: Ie7a8327fac62a0608b60cf9f0f072f979ac4fd76
Reviewed-on: https://chromium-review.googlesource.com/443528
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@google.com>
Cr-Commit-Position: refs/heads/master@{#43269}
2017-02-17 10:06:22 +00:00
bbudge
deabb19abc Remove SIMD.js from V8.
LOG=Y
BUG=v8:4124,v8:5948
R=bradnelson@chromium.org,bmeurer@chromium.org,jochen@chromium.org,hpayer@chromium.org,danno@chromium.org

Review-Url: https://codereview.chromium.org/2684313003
Cr-Original-Original-Commit-Position: refs/heads/master@{#43162}
Committed: d170c57ab9
Review-Url: https://codereview.chromium.org/2684313003
Cr-Original-Commit-Position: refs/heads/master@{#43169}
Committed: a9b59a11f1
Review-Url: https://codereview.chromium.org/2684313003
Cr-Commit-Position: refs/heads/master@{#43176}
2017-02-14 06:57:25 +00:00
franzih
a386eb4f04 Revert of Remove SIMD.js from V8. (patchset #7 id:120001 of https://codereview.chromium.org/2684313003/ )
Reason for revert:
Breaks Node integration build.

Original issue's description:
> Remove SIMD.js from V8.
>
> LOG=Y
> BUG=v8:4124,v8:5948
> R=bradnelson@chromium.org,bmeurer@chromium.org,jochen@chromium.org,hpayer@chromium.org,danno@chromium.org
>
> Review-Url: https://codereview.chromium.org/2684313003
> Cr-Original-Commit-Position: refs/heads/master@{#43162}
> Committed: d170c57ab9
> Review-Url: https://codereview.chromium.org/2684313003
> Cr-Commit-Position: refs/heads/master@{#43169}
> Committed: a9b59a11f1

TBR=bradnelson@chromium.org,bmeurer@chromium.org,jochen@chromium.org,hpayer@chromium.org,danno@chromium.org,bradnelson@google.com,machenbach@chromium.org,bbudge@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4124,v8:5948

Review-Url: https://codereview.chromium.org/2695653005
Cr-Commit-Position: refs/heads/master@{#43170}
2017-02-13 21:33:46 +00:00
bbudge
a9b59a11f1 Remove SIMD.js from V8.
LOG=Y
BUG=v8:4124,v8:5948
R=bradnelson@chromium.org,bmeurer@chromium.org,jochen@chromium.org,hpayer@chromium.org,danno@chromium.org

Review-Url: https://codereview.chromium.org/2684313003
Cr-Original-Commit-Position: refs/heads/master@{#43162}
Committed: d170c57ab9
Review-Url: https://codereview.chromium.org/2684313003
Cr-Commit-Position: refs/heads/master@{#43169}
2017-02-13 20:43:08 +00:00
bradnelson
43fc15bb79 Revert of Remove SIMD.js from V8. (patchset #7 id:120001 of https://codereview.chromium.org/2684313003/ )
Reason for revert:
red

Original issue's description:
> Remove SIMD.js from V8.
>
> LOG=Y
> BUG=v8:4124,5948
> R=bradnelson@chromium.org,bmeurer@chromium.org,jochen@chromium.org,hpayer@chromium.org,danno@chromium.org
> (notry since trybots can't patch directory deletes)
> NOTRY=true
>
> Review-Url: https://codereview.chromium.org/2684313003
> Cr-Commit-Position: refs/heads/master@{#43162}
> Committed: d170c57ab9

TBR=bmeurer@chromium.org,jochen@chromium.org,hpayer@chromium.org,danno@chromium.org,bradnelson@google.com,bbudge@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4124,5948

Review-Url: https://codereview.chromium.org/2692933002
Cr-Commit-Position: refs/heads/master@{#43164}
2017-02-13 18:12:14 +00:00
bbudge
d170c57ab9 Remove SIMD.js from V8.
LOG=Y
BUG=v8:4124,5948
R=bradnelson@chromium.org,bmeurer@chromium.org,jochen@chromium.org,hpayer@chromium.org,danno@chromium.org
(notry since trybots can't patch directory deletes)
NOTRY=true

Review-Url: https://codereview.chromium.org/2684313003
Cr-Commit-Position: refs/heads/master@{#43162}
2017-02-13 15:59:22 +00:00
Marja Hölttä
e425079b1d [iwyu] Remove include debug.h -> arguments.h
arguments.h is one of the headers including objects-inl.h. Files needing
objects-inl.h used to innocently pull in debug.h, so that needs to be fixed now
too.

BUG=v8:5294
R=mstarzinger@chromium.org

Change-Id: I8ce671c533ed757103ef9a3b0bf0a0509230fdd8
Reviewed-on: https://chromium-review.googlesource.com/439287
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43054}
2017-02-09 09:19:23 +00:00
mvstanton
aea3ce3df3 [TypeFeedbackVector] Root feedback vectors at function literal site.
TypeFeedbackVectors are strongly rooted by a closure. However, in modern
JavaScript closures are created and abandoned more freely. An important
closure may not be present in the root-set at time of garbage collection,
even though we've cached optimized code and use it regularly. For
example, consider leaf functions in an event dispatching system. They may
well be "hot," but tragically non-present when we collect the heap.

Until now, we've relied on a weak root to cache the feedback vector in
this case. Since there is no way to signal intent or relative importance,
this weak root is as susceptible to clearing as any other weak root at
garbage collection time.

Meanwhile, the feedback vector has become more important. All of our
ICs store their data there. Literal and regex boilerplates are stored there.
If we lose the vector, then we not only lose optimized code built from
it, we also lose the very feedback which allowed us to create that optimized
code. Therefore it's vital to express that dependency through the root
set.

This CL does this by creating a strong link to a feedback
vector at the instantiation site of the function closure.
This instantiation site is in the code and feedback vector
of the outer closure.

BUG=v8:5456

Review-Url: https://codereview.chromium.org/2674593003
Cr-Commit-Position: refs/heads/master@{#42953}
2017-02-06 10:18:05 +00:00
mlippautz
e00eae9e89 [api] Mark functions related to object grouping as DEPRECATE_SOON
Embedders should use the EmbedderHeapTracer API.

BUG=v8:5828

Review-Url: https://codereview.chromium.org/2628893003
Cr-Commit-Position: refs/heads/master@{#42269}
2017-01-12 14:02:21 +00:00
mvstanton
38602f1ff5 [FeedbackVector] Infrastructure for literal arrays in the vector.
This changes the NewClosure interface descriptor, but ignores
the additional vector/slot arguments for now. The feedback vector
gets larger, as it holds a space for each literal array. A follow-on
CL will constructively use this space.

BUG=v8:5456

Review-Url: https://codereview.chromium.org/2614373002
Cr-Commit-Position: refs/heads/master@{#42146}
2017-01-09 15:31:00 +00:00
ulan
b00fc8be8a Use std::deque for storing edges and children in heap snapshot.
This patch fixes OOM crash that happens for large heap where
the total size of edges exceeds 2GB, which is the hard limit
for v8::internal::List allocated using tcmalloc.

BUG=chromium:675911

Review-Url: https://codereview.chromium.org/2595003002
Cr-Commit-Position: refs/heads/master@{#42004}
2016-12-30 16:27:15 +00:00
hablich
aa8a208a47 Revert of [TypeFeedbackVector] Root literal arrays in function literals slots (patchset #11 id:370001 of https://codereview.chromium.org/2504153002/ )
Reason for revert:
Speculative revert because of blocked roll: https://codereview.chromium.org/2596013002/

Original issue's description:
> [TypeFeedbackVector] Root literal arrays in function literals slots
>
> Literal arrays and feedback vectors for a function can be garbage
> collected if we don't have a rooted closure for the function, which
> happens often. It's expensive to come back from this (recreating
> boilerplates and gathering feedback again), and the cost is
> disproportionate if the function was inlined into optimized code.
>
> To guard against losing these arrays when we need them, we'll now
> create literal arrays when creating the feedback vector for the outer
> closure, and root them strongly in that vector.
>
> BUG=v8:5456
>
> Review-Url: https://codereview.chromium.org/2504153002
> Cr-Commit-Position: refs/heads/master@{#41893}
> Committed: 93df094081

TBR=bmeurer@chromium.org,mlippautz@chromium.org,mvstanton@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:5456

Review-Url: https://codereview.chromium.org/2597163002
Cr-Commit-Position: refs/heads/master@{#41917}
2016-12-22 10:26:36 +00:00
mvstanton
93df094081 [TypeFeedbackVector] Root literal arrays in function literals slots
Literal arrays and feedback vectors for a function can be garbage
collected if we don't have a rooted closure for the function, which
happens often. It's expensive to come back from this (recreating
boilerplates and gathering feedback again), and the cost is
disproportionate if the function was inlined into optimized code.

To guard against losing these arrays when we need them, we'll now
create literal arrays when creating the feedback vector for the outer
closure, and root them strongly in that vector.

BUG=v8:5456

Review-Url: https://codereview.chromium.org/2504153002
Cr-Commit-Position: refs/heads/master@{#41893}
2016-12-21 14:06:29 +00:00