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  1. 09 Jun, 2021 6 commits
    • Maya Lekova's avatar
      Revert "heap: Fix initial GC configuration for C++-only heaps" · 4acc0358
      Maya Lekova authored 
      This reverts commit 7ef67b2e.

Reason for revert: Speculative revert for a blocked roll - https://chromium-review.googlesource.com/c/chromium/src/+/2947365

Original change's description:
> heap: Fix initial GC configuration for C++-only heaps
>
> Heaps in V8 start with a large limit that is shrunk upon young
> generation GCs, based on some liveness estimate. This provides best
> throughput during startup while at the same time finding a reasonable
> first limit.
>
> For C++ (embedder memory) there is no estimate which is why it was
> piggy-backing on V8. This breaks in scenarios where no JS memory is
> allocated.
>
> In this fix we start a memory reducer after embedder memory has hit
> the activation threshold if no GC happened so far. As soon as a single
> Scavenger has happened, we leave it up to the JS estimate to figure
> out a limit. Memory reducing GCs will then find a regular limit based
> on the initial live size.
>
> Drive-by: Give embedders the same activiation threshold of 8MB as JS.
>
> Bug: chromium:1217076
> Change-Id: I8469696002ac2af8d75d6b47def062d2608387a1
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2944935
> Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
> Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#75012}

Bug: chromium:1217076
Change-Id: Ic1530162e846c2a767ea5ea902a01a21967d8e35
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2947419
Auto-Submit: Maya Lekova <mslekova@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@{#75034}
      4acc0358
    • Jakob Gruber's avatar
      [compiler] RawFastPropertyAt without serialization · 9bfd401e
      Jakob Gruber authored 
      This is a step towards making JSObjectRef non-serialized.

Change JSObjectRef::RawFastPropertyAt to use a direct load with
relaxed semantics. Special handling of `uninitialized` sentinel values
is moved to the only use-site.

A new lock `boilerplate_migration_access` protects against concurrent
boilerplate migrations while we are iterating over properties.

Bug: v8:7790
Change-Id: Ic9de54ca16c1f3364d497a77058cfa33d48dd4a4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2928184
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75033}
      9bfd401e
    • Maya Lekova's avatar
      Revert "Update V8 DEPS." · 75d9e3b8
      Maya Lekova authored 
      This reverts commit eb3ce72b.

Reason for revert: Broke Android Arm64 Builder, see https://bugs.chromium.org/p/chromium/issues/detail?id=1217912

Original change's description:
> Update V8 DEPS.
>
> Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/8870cb4..921ea58
>
> Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/a8bae77..df0a59a
>
> Rolling v8/third_party/depot_tools: https://chromium.googlesource.com/chromium/tools/depot_tools/+log/b508ecd..b14cdae
>
> Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/0c64e83..d987b04
>
> TBR=v8-waterfall-sheriff@grotations.appspotmail.com,mtv-sf-v8-sheriff@grotations.appspotmail.com
>
> Change-Id: I8906ce650c866bd771910fea5db6c735bfe0c7e2
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2947396
> Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
> Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
> Cr-Commit-Position: refs/heads/master@{#75029}

Change-Id: I4d83f012cf04ab94eb66bab9a8ebec04ed098fbf
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2947417
Auto-Submit: Maya Lekova <mslekova@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@{#75032}
      75d9e3b8
    • Iain Ireland's avatar
      [regexp] Propagate eats_at_least for negative lookahead · 363ab5ae
      Iain Ireland authored 
      In issue 11290, we disabled the propagation of EAL data out of
lookarounds, because it was incorrect for lookahead nodes in
loops. This caused performance regressions: for example,
`/^\P{Letter}+$/u` (matching only characters that are not in Unicode's
Letter category) uses negative lookahead when matching lone
surrogates, and became about 2x slower. I spent some time looking into
fixes, and this is what I've settled on.

Some background: the implementation of lookarounds in irregexp is
split between positive and negative lookaheads. (Lookbehinds aren't
relevant here, because backwards matches always have EAL=0.)  Positive
lookaheads are wrapped in BEGIN_SUBMATCH and POSITIVE_SUBMATCH_SUCCESS
ActionNodes. BEGIN_SUBMATCH saves the current state.
POSITIVE_SUBMATCH_SUCCESS restores the necessary state (while leaving
any captures that occurred during the lookaround intact).

Negative lookaheads also begin with a BEGIN_SUBMATCH node, but follow
it with a NegativeLookaroundChoiceNode. This node has two successors:
a lookaround node, and a continue node. It only executes the continue
node if the lookaround node backtracks, which automatically restores
the previous state. Negative lookarounds also can't update captures.

This affects EAL calculations. It turns out that negative lookaheads
are already doing the right thing: EatsAtLeastPropagator only
propagates information from the continue node, ignoring the lookaround
node. The same is true for quick checks (see the comment in
RegExpLookaround:Builder::ForMatch). A BEGIN_SUBMATCH for a negative
lookahead can simply propagate the EAL data from its successor like
any other ActionNode, and everything works.

Positive lookaheads are harder. I tried saving a pointer to the
successor in BEGIN_SUBMATCH, but ran into problems in FillInBMInfo,
because the EAL value corresponded to the nodes after the lookahead,
but the analysis was still looking at the nodes inside. I fell back
to a more modest approach: split BEGIN_SUBMATCH in two, and propagate
EAL info for BEGIN_NEGATIVE_SUBMATCH while keeping the current
behaviour for BEGIN_POSITIVE_SUBMATCH. This fixes the performance
regression at hand.

Two potential approaches for fixing EAL for positive lookahead are:
 1. Handling positive lookahead with its own dedicated choice node,
    like NegativeLookaroundChoiceNode.
 2. Adding an eats_at_least_inside_loop field to EatsAtLeastInfo,
    which is <= eats_at_least_from_possibly_start, and using that
    value in EatsAtLeastFromLoopEntry.

Both of those approaches are more complex than I want to tackle
right now, though.

Bug: v8:11844
Change-Id: I2a43509c2c21194b8c18f0a587fa21c194db76c2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2934858Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75031}
      363ab5ae
    • Frank Tang's avatar
      Address flaky tests · 4a78a7d0
      Frank Tang authored 
      The test push stack boundary and too flaky (timeout) while
running machine with more memory.

Bug: v8:11845
Change-Id: I5b603f05270d224de71c735ece5dd65a27311c25
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2939082Reviewed-by: 's avatarShu-yu Guo <syg@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75030}
      4a78a7d0
    • v8-ci-autoroll-builder's avatar
      Update V8 DEPS. · eb3ce72b
      v8-ci-autoroll-builder authored 
      Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/8870cb4..921ea58

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/a8bae77..df0a59a

Rolling v8/third_party/depot_tools: https://chromium.googlesource.com/chromium/tools/depot_tools/+log/b508ecd..b14cdae

Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/0c64e83..d987b04

TBR=v8-waterfall-sheriff@grotations.appspotmail.com,mtv-sf-v8-sheriff@grotations.appspotmail.com

Change-Id: I8906ce650c866bd771910fea5db6c735bfe0c7e2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2947396Reviewed-by: 's avatarv8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#75029}
      eb3ce72b
  3. 08 Jun, 2021 30 commits
  5. 07 Jun, 2021 4 commits