This current fails, since {mmap} fails with EINVAL for empty mappings.
The destructor already has special handling for a {nullptr} mapping, so
we can just use {nullptr} for empty files. We get a similar error on
windows, and can fix it the same way.

On order to make presubmit checks happy, we have to skip copyright
checking and checking for terminating newlines for empty files.

R=mlippautz@chromium.org

Change-Id: I2b73da7ff6df72d8bdd40df1fff6422e0a46881e
Reviewed-on: https://chromium-review.googlesource.com/c/1424861Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58970}

This removes the unused "argument count" field from the safepoint table
as the field was unused by now and always contained the value zero.

Also note that associating a callee's argument count with the call-site
is not compatible with tail-call support. When tail-calling a function
with a different number of arguments, the information associated with
the call-site becomes stale. The number of arguments is a property of
the callee, not of the call-site in the caller. For this reason the
field in question is not usable to support reference types in function
arguments (at least when tail-calls are also supported).

R=ahaas@chromium.org

Change-Id: If667d729267f2dd2642b755c54235cc08ca9b141
Reviewed-on: https://chromium-review.googlesource.com/c/1402548Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58969}

Walk the VariableMap instead of the ast.

Change-Id: I03ee9145230bcbfe04c5e31dc8d8b3a98a00a4be
Reviewed-on: https://chromium-review.googlesource.com/c/1424865
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58968}

This CL adds handling for Construct bytecode to the serializer
for backgorund compilation, similar to the hanling of Call* bytecodes.

Design doc:
https://docs.google.com/document/d/1vCQYhtFPqXafSMweSnGD8l0TKEIB6cPV5UGMHJtpy8k/edit?ts=5bf7d341

Bug: v8:7790
Change-Id: If518ba44fff18c1b30fdf5c764bdb9e77886af78
Reviewed-on: https://chromium-review.googlesource.com/c/1424947
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58967}

The purpose of the {WireBytesStorage} (typically held in a shared_ptr
itself) is to keep the actual wire bytes alive. Thus implement it this
way for the {NativeModuleWireBytesStorage}.

R=mstarzinger@chromium.org

Bug: v8:8689
Change-Id: I8f171b4fa8b80b517badb1b1d3228503a32830dd
Reviewed-on: https://chromium-review.googlesource.com/c/1421362
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58966}

Change-Id: Id9955037b2de03d151e038f57f922429d85f06b3
Reviewed-on: https://chromium-review.googlesource.com/c/1425197
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58965}

BUG=chromium:919394

Change-Id: I99d0b557f8d52c87c4422cd971a43211e5d5e849
Reviewed-on: https://chromium-review.googlesource.com/c/1425198Reviewed-by: Dan Elphick <delphick@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58964}

The change is just a refactoring without functional changes.

Bug: chromium:923361
Change-Id: Ie633c56122ff72658f0238dc40db698350a7b8e7
Reviewed-on: https://chromium-review.googlesource.com/c/1421363
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58963}

This reverts commit bfc9eb2e.

Reason for revert: Micro-benchmark regressions (crbug.com/923823)

Original change's description:
> [scanner] Micro-optimize AdvanceUntil
> 
> Replace std::find_if in AdvanceUntil with a manual loop, which can
> then return early, skipping the branch comparing to buffer_end_.
> 
> Change-Id: If49ed3667877751fcb0103a742750f03e5bd50db
> Reviewed-on: https://chromium-review.googlesource.com/c/1411351
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Commit-Queue: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58846}

TBR=leszeks@chromium.org,verwaest@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.
Bug: 923823

Change-Id: I2475e18fb1d52d47b32b34e261c6f1aa46b3c1ce
Reviewed-on: https://chromium-review.googlesource.com/c/1425200Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58962}

The temp registers might be needed by the assembler, so avoid using them
in LiftoffAssembler. Use Liftoff cache registers instead. This might
introduce additional spills if all registers are in use, but this is
unlikely.

This also simplifies the logic to ensure non-aliasing of certain
registers.

R=ahaas@chromium.org

Bug: chromium:922933, v8:6600
Change-Id: Ie929d9de0b6f4f41c6117d820b6a367dd0a342f7
Reviewed-on: https://chromium-review.googlesource.com/c/1424862Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58961}

This allows us to stop tracking variables_ in the preparser.

This currently makes us track slightly more variables than neccessary in the
case `for (var ...` since `var ... of` needs to check conflicts with out simple
catch variables. We should probably track the names through a ScopedPtrList
instead of a ZonePtrList anyway. Then it won't matter anymore.

Change-Id: I64e3f9ab13af8269456439cf15b0bc4d5b9e5380
Reviewed-on: https://chromium-review.googlesource.com/c/1421360Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58960}

This is a reland of 4e1d7c87.
Failure on arm and arm64 is fixed by https://crrev.com/c/1411885.

Original change's description:
> [wasm] Split compilation in three stages
>
> In order to refactor ownership between objects in wasm compilation, the
> compilation (executed by background tasks) is split in three stages:
> getting a compilation unit (while holding a mutex), executing the work
> (without any mutex and without keeping the NativeModule alive), and
> submitting the work (with a mutex again).
>
> This CL prepares this design by splitting compilation from submission.
> Both steps are still executed right after each other. This will be
> changed in a follow-up CL.
>
> R=titzer@chromium.org
> CC=mstarzinger@chromium.org
>
> Bug: v8:8689
> Change-Id: I2f92aee8e2f2d45470d8c63314ed026341630902
> Reviewed-on: https://chromium-review.googlesource.com/c/1414920
> Reviewed-by: Ben Titzer <titzer@chromium.org>
> Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58929}

TBR=titzer@chromium.org

Bug: v8:8689
Change-Id: I58ff07d0e0ac8df0f6ee23c416f992954f4673d2
Reviewed-on: https://chromium-review.googlesource.com/c/1422748Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58959}

This extends the CodeReference class to be able to hold a pointer to
a CodeDesc struct which represents finished but unpublished wasm
code.
For readability, it refactors the implementation of the dispatch for
the different CodeReference kinds.

R=mstarzinger@chromium.org

Bug: v8:8689
Change-Id: Idd031dffaa9d80740c073b6cca0fc3561c5df0c1
Reviewed-on: https://chromium-review.googlesource.com/c/1411885
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58958}

- Use unique ptrs for owned objects
- Remove friendship with CpuProfiler and replace with public API
- Remove unused method LogFailure()
- Remove StopProfiler() which was only used by LogFailure() (removed)
  and one test, which can use StopProfilerThread() instead
- Remove 'paused' state which was only used by the above
- Remove 'engage' state. There is no reason we need this as along as
  users keep track of Engage/Disengage calls

Drive-by cleanup:
- Remove import of log.h from profile-generator.h
- Remove unnecessary includes of log.h

Change-Id: Ifc4ca156bef038c40953f8361ffea17788e3a59b
Reviewed-on: https://chromium-review.googlesource.com/c/1424338
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58957}

Fix fixes a minor DCHECK error, which fired because usually only
LiftoffRegisters of the same type should be compared against each
other. In the RegisterReuseMap we store both register pairs and single
registers, hence check for pair vs non-pair comparisons explicitly.

R=ahaas@chromium.org

Bug: v8:6600, chromium:922670
Change-Id: I18beb61b6b1906cc42bcf6e7dfdd5eb803e874d7
Reviewed-on: https://chromium-review.googlesource.com/c/1421921Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58956}

Simplify the internal state of Sampler a bit. There are basically two
users of Sampler - the CpuSampler used by the CpuProfiler and the
Ticker used by log.cc. Ticker calls Start/Stop to manage the Sampler
lifetime, but CpuProfiler does not. This leads to much confusion and
overlap of functionality.

Fix that here by removing the distinction between active, registered
and isProfiling states. These are now all the same thing and are
represented by IsActive(). The state is set to active when Start is
called, and set inactive when Stop is called. Both users of Sampler
now call Start and Stop at appropriate times.

The concept of profiling depth was not used - each Sampler would
only ever have a sampling depth of 1. We still need to call
SignalHandler::IncreaseSamplerCount(), so we do that in Start
and the corresponding DecreaseSamplerCount() in Stop.

Change-Id: I16a9435d26169a7dd00b1c7876e66af45f12e4b0
Reviewed-on: https://chromium-review.googlesource.com/c/1424337
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58955}

Use variable tracking from ExpressionScopes rather than the PatternRewriter and
PreParserExpression::variables_ to declare variables.

We only figure out that variables are non-simple parameters once we see the
first non-simple parameter. This still uses the pattern rewriter to make
variables non-simple (kLet instead of kVar).

Change-Id: I4a4ee4852d667c26806bb24896722cfea3e093f2
Reviewed-on: https://chromium-review.googlesource.com/c/1417630Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58954}

Since the PreparseData now directly contains the byte data inline it can
grow very large as well.

Bug: chromium:923264
Change-Id: I456d5bcbfb40587b283584f726d9e084061fd30f
Reviewed-on: https://chromium-review.googlesource.com/c/1421321Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58953}

This CL adds a stack check to the TFS builtin "FlattenIntoArray" as it
is called recursively and can cause a SEGV with a large enough
"depth" argument.

R=jgruber@chromium.org

Bug: v8:8708
Change-Id: I833506531bcff1c4703b9a21678028cf0e63638d
Reviewed-on: https://chromium-review.googlesource.com/c/1424858
Commit-Queue: Simon Zünd <szuend@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58952}

With and without infra_staging flag testrunner behaves the same for old
features. This CL removes duplicate tests testing the same behavior.

R=machenbach@chromium.org
CC=yangguo@chromium.org,sergiyb@chromium.org

No-Try: true
Bug: v8:8174
Change-Id: Icf7bea15b2343b90697016d050fa0d918a99997d
Reviewed-on: https://chromium-review.googlesource.com/c/1424859Reviewed-by: Sergiy Belozorov <sergiyb@chromium.org>
Commit-Queue: Tamer Tas <tmrts@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58951}

There's no reason to use our self-baked atomics anymore. Also

- Changes two boolean values to use a boolean instead of an int
- Uses a unique ptr for data_
- Removes has_processing_thread_ which is not used
- Moves most initialization inline into the class
- Removes SetUp/TearDown which weren't needed

Change-Id: I8f50133636961502d56351abd2fb17196603a01a
Reviewed-on: https://chromium-review.googlesource.com/c/1422918
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58950}

Bug: chromium:923723
Change-Id: Ic397642c2e803b2ada95fa87ece31032eb104782
Reviewed-on: https://chromium-review.googlesource.com/c/1424857
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58949}

With this change, we use the same heuristics for picking free registers
and for picking a blocked register to spill. This is mostly cleanup to
make results less surprising.

Change-Id: I09d031c758ffbd02798d573bc9e68a474e916418
Reviewed-on: https://chromium-review.googlesource.com/c/1411607
Commit-Queue: Stephan Herhut <herhut@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58948}

This is part of an effort to improve the performance of TA#subarray.

Bug: v8:7161
Change-Id: Iae84d16a037386bebfeaa7e8fb0648da295653b4
Reviewed-on: https://chromium-review.googlesource.com/c/1419225
Commit-Queue: Peter Wong <peter.wm.wong@gmail.com>
Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58947}

Moved class definitions into header

Change-Id: I2d3e5ec6f8f5068284cdbaa6900797950fc7e01a
Reviewed-on: https://chromium-review.googlesource.com/c/1422739
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58946}

There is no reason to use the custom map here anymore. This lets us
get rid of the custom hash and a lot of casts.

We can also store the SamplerList by value in the map rather than a
pointer, then we don't have to manage the lifetime explicitly.

Also move the SamplerList typedef inside of SamplerManager because it's
an internal detail. Remove the include for <map> because we aren't using
this anywhere anyway.

Change-Id: I787a1b6c3ffc331ec3f36e66d5e07bd115c4cbb4
Reviewed-on: https://chromium-review.googlesource.com/c/1419317Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58945}

Moving to a lazy test loading approach makes counting the total number of tests
non-trivial.

For CI runs, we output the total number of tests after the run.
For users, progress indicator signals the status of the run.

R=machenbach@chromium.org
CC=​yangguo@chromium.org,sergiyb@chromium.org

Bug: v8:8174
Change-Id: I0731964515aac60a3629acee6c7243433a2b4e04
Reviewed-on: https://chromium-review.googlesource.com/c/1420677
Commit-Queue: Tamer Tas <tmrts@chromium.org>
Reviewed-by: Sergiy Belozorov <sergiyb@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58944}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/213e0a3..402bc6d

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: If20446c4127d59fd9e7c5055c9594f4fae164d27
Reviewed-on: https://chromium-review.googlesource.com/c/1424278Reviewed-by: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: Sergiy Belozorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58943}

TBR=sergiyb@chromium.org

No-Try: true
Bug: chromium:922125
Change-Id: I58e6e2f3525293df0a6513611e16cd21b65e3985
Reviewed-on: https://chromium-review.googlesource.com/c/1418191
Commit-Queue: Sergiy Belozorov <sergiyb@chromium.org>
Reviewed-by: Sergiy Belozorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58942}

Fix WebAssembly's table/get-set js-api. The argument is a unsigned long,
this change refactors most of arithmetic and bounds checks type from
int64 to uint32_t, according to the spec.

Bug: v8:8319
Change-Id: I088f631c6805b0e5ba29089b08ea15e78fe5852d
Cq-Include-Trybots: luci.chromium.try:linux-blink-rel
Reviewed-on: https://chromium-review.googlesource.com/c/1414914Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Sven Sauleau <ssauleau@igalia.com>
Cr-Commit-Position: refs/heads/master@{#58941}

Rolling v8/build: https://chromium.googlesource.com/chromium/src/build/+log/43021de..213e0a3

Rolling v8/buildtools: https://chromium.googlesource.com/chromium/buildtools/+log/40194ab..2f02e1f

Rolling v8/third_party/catapult: https://chromium.googlesource.com/catapult/+log/a0e5e33..fab27df

Rolling v8/third_party/depot_tools: https://chromium.googlesource.com/chromium/tools/depot_tools/+log/deab113..f797143

Rolling v8/third_party/icu: https://chromium.googlesource.com/chromium/deps/icu/+log/d653014..07e7295

Rolling v8/tools/clang: https://chromium.googlesource.com/chromium/src/tools/clang/+log/9f413ce..3a16568

TBR=machenbach@chromium.org,hablich@chromium.org,sergiyb@chromium.org

Change-Id: Ia3a87da427e0efd4cc1fa4f43bd8672754f75d2f
Reviewed-on: https://chromium-review.googlesource.com/c/1423326Reviewed-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@{#58940}

Rolling v8/test/test262/data: https://chromium.googlesource.com/external/github.com/tc39/test262/+log/af984c0..4f1155

Bug: v8:7834
Change-Id: I6eeff251b9a3a773b386d7963981dc72f48d6e44
Reviewed-on: https://chromium-review.googlesource.com/c/1423096Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Frank Tang <ftang@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58939}

See https://github.com/tc39/proposal-intl-list-format/pull/36

Bug: v8:8614
Change-Id: Ifa9bebf27163420562c0d62867b9a240b5c4c502
Reviewed-on: https://chromium-review.googlesource.com/c/1386324
Commit-Queue: Frank Tang <ftang@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58938}

Use more idiomatic c++ and add slightly better comments.

Change-Id: Id6397a25851915eb10a0370d23dc41ca7fce3c2e
Reviewed-on: https://chromium-review.googlesource.com/c/1418194Reviewed-by: Alexei Filippov <alph@chromium.org>
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58937}

Fix WebAssembly's table/grow js-api. The argument is a unsigned long,
this change refactors most of arithmetic and bounds checks type from
int64 to uint32_t, according to the spec.

Bug: v8:8319
Cq-Include-Trybots: luci.chromium.try:linux-blink-rel
Change-Id: Ia29121c930d7fb930668e54a5a769dae25234f2c
Reviewed-on: https://chromium-review.googlesource.com/c/1351006
Commit-Queue: Sven Sauleau <ssauleau@igalia.com>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58936}

Though I'm not (yet) a much of a wasm code expert, I have made and
reviewed a number of changes to this file, and feel pretty comfortable
with it, so I figured it might be reasonable starting place.

Change-Id: I8d5d0b219def6adeba52e752467bb0405554ee01
Reviewed-on: https://chromium-review.googlesource.com/c/1418593Reviewed-by: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58935}

v8::Isolate::kAttemptOverrideReadOnlyOnPrototypeSloppy and
v8::Isolate::kAttemptOverrideReadOnlyOnPrototypeStrict are no longer
incremented.

BUG=v8:8175
R=gsathya@chromium.org, littledan@chromium.org

Change-Id: Ia5f8f9226a54d88c15a3c3b4a5941d774eb1834a
Reviewed-on: https://chromium-review.googlesource.com/c/1417381Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Caitlin Potter <caitp@igalia.com>
Cr-Commit-Position: refs/heads/master@{#58934}

Turns on --harmony-hashbang when experimental JS features are enabled.

BUG=v8:8523
R=gsathya@chromium.org, adamk@chromium.org

Change-Id: I2b1e6c146d900cb8a998060b4b93127f907b6728
Reviewed-on: https://chromium-review.googlesource.com/c/1417382Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Caitlin Potter <caitp@igalia.com>
Cr-Commit-Position: refs/heads/master@{#58933}

This reverts commit 4e1d7c87.

Reason for revert:
https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux%20-%20arm%20-%20sim%20-%20debug/14986

Original change's description:
> [wasm] Split compilation in three stages
> 
> In order to refactor ownership between objects in wasm compilation, the
> compilation (executed by background tasks) is split in three stages:
> getting a compilation unit (while holding a mutex), executing the work
> (without any mutex and without keeping the NativeModule alive), and
> submitting the work (with a mutex again).
> 
> This CL prepares this design by splitting compilation from submission.
> Both steps are still executed right after each other. This will be
> changed in a follow-up CL.
> 
> R=​titzer@chromium.org
> CC=​mstarzinger@chromium.org
> 
> Bug: v8:8689
> Change-Id: I2f92aee8e2f2d45470d8c63314ed026341630902
> Reviewed-on: https://chromium-review.googlesource.com/c/1414920
> Reviewed-by: Ben Titzer <titzer@chromium.org>
> Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#58929}

TBR=titzer@chromium.org,clemensh@chromium.org

Change-Id: Ic3d0287b354ef5f834b76bc2cdc096d2231f4477
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:8689
Reviewed-on: https://chromium-review.googlesource.com/c/1422917Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58932}

- Introduce NodeSpace that holds allocation related logic.
- Provide std compatible iterator for node iteration.

This allows for creating a different internal node type.

The change is just a refactoring without functional changes.

Bug: chromium:923361
Change-Id: I424f821d96b3a82f64024aedff6c289d3eec11a2
Reviewed-on: https://chromium-review.googlesource.com/c/1418192
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58931}