The hand-written KeyedLoadIC_Megamorphic stub didn't care about JSArray
lengths, which made it lenient towards said lengths being wrong, but it
will soon fix that bug and thereby become more strict.

LiveEdit: factory->NewJSArray(capacity) doesn't set a length, so set it
manually.
RegExp: to avoid having to take care of array length updating in the
RegExpExecStub, just use a JSObject instead.

Review-Url: https://codereview.chromium.org/2244673002
Cr-Commit-Position: refs/heads/master@{#38624}

Revert of [interpreter] Inline ForInFilter stub. (patchset #1 id:1 of https://codereview.chromium.org/2220343002/ )

Reason for revert:
Speculative revert to possible performance regressions.

BUG=chromium:635826,chromium:635930

Original issue's description:
> [interpreter] Inline ForInFilter stub.
>
> BUG=v8:4280
> LOG=N
>
> Committed: https://crrev.com/2bf0b8c8ed5d0c93982c8c227e93622aceecea16
> Cr-Commit-Position: refs/heads/master@{#38420}

TBR=oth@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=v8:4280

Review-Url: https://codereview.chromium.org/2238283002
Cr-Commit-Position: refs/heads/master@{#38623}

    Instead of loading 64 bits and shifting:

      ldr x0, [x1, #offset]
      asr x0, x0, #32

    directly load the interesting 32 bits and sign-extend:

      ldrsw x0, [x1, #offset+4]

BUG=

Review-Url: https://codereview.chromium.org/2243843002
Cr-Commit-Position: refs/heads/master@{#38622}

R=jgruber@chromium.org, mstarzinger@chromium.org
BUG=v8:5265

Review-Url: https://codereview.chromium.org/2246483002
Cr-Commit-Position: refs/heads/master@{#38621}

This adds a shortcut to the compilation pipeline that makes sure we are
not regenerating bytecode when it has been preserved from a previous
request. This can happen when code flushing removes baseline code,
thereby clearing the entry trampoline but leaving bytecode intact.

R=yangguo@chromium.org
BUG=v8:5265

Review-Url: https://codereview.chromium.org/2241783002
Cr-Commit-Position: refs/heads/master@{#38620}

kudos to marja@ for finding this

BUG=v8:5209

Review-Url: https://codereview.chromium.org/2243833002
Cr-Commit-Position: refs/heads/master@{#38619}

Also, re-enables the use of the type feedback in BytecodeGraphBuilder.

BUG=v8:5273
LOG=N

Review-Url: https://codereview.chromium.org/2235133003
Cr-Commit-Position: refs/heads/master@{#38618}

This removes some compiler internals as well as some JavaScript specific
helper from the CodeAssembler, by either hiding or moving the support
into the CodeStubAssembler.

R=bmeurer@chromium.org

Review-Url: https://codereview.chromium.org/2246463002
Cr-Commit-Position: refs/heads/master@{#38617}

This should be faster and should give the same result.

BUG=v8:5203

Review-Url: https://codereview.chromium.org/2243783002
Cr-Commit-Position: refs/heads/master@{#38616}

Properly deoptimize if the left hand side of a CheckedInt32Mod is
negative and the result of the operation is zero.

R=jarin@chromium.org
BUG=v8:5286

Review-Url: https://codereview.chromium.org/2243803002
Cr-Commit-Position: refs/heads/master@{#38615}

With --ignition-preserve-bytecode, we don't have the guarantee that
SharedFunctionInfo::abstract_code() returns the code we deopt to.

R=mstarzinger@chromium.org
BUG=v8:5265

Review-Url: https://codereview.chromium.org/2239773003
Cr-Commit-Position: refs/heads/master@{#38614}

Revert of "[heap] Switch to 500k pages" (patchset #11 id:220001 of https://codereview.chromium.org/2232653003/ )

Reason for revert:
Breaks benchmark with --turbo on avx2

https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20-%20avx2/builds/9895

Original issue's description:
> Reland of "[heap] Switch to 500k pages"
>
> Decrease regular heap object size to 400k. In a follow up, we can now get rid of
> the new space border page while keeping the 1M minimum new space size.
>
> BUG=chromium:636331
>
> This reverts commit 555c9619.
>
> Committed: https://crrev.com/20e2ea80e169e85c5b8231adc02901fb6c989609
> Cr-Commit-Position: refs/heads/master@{#38608}

TBR=hpayer@chromium.org,yangguo@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:636331

Review-Url: https://codereview.chromium.org/2239323002
Cr-Commit-Position: refs/heads/master@{#38613}

BUG=

Review-Url: https://codereview.chromium.org/2240803003
Cr-Commit-Position: refs/heads/master@{#38612}

This bug was triggered by a very specific combination:

* A context-allocated variable at script scope.
* OSR optimization.
* A scheduled breakpoint, which triggers at stack checks.

Stack checks differ from other possible breakpoint locations in that
the context (among other things) may be in a register and not on the
stack, making it impossible to recover during deoptimization. The
frame_inspector then returns undefined when asked for the context.

In GetFrameDetails, handle this case by omitting all context-allocated
variables.

BUG=v8:5279

Review-Url: https://codereview.chromium.org/2245603002
Cr-Commit-Position: refs/heads/master@{#38611}

This test would have failed prior to 58524d6d.

R=verwaest@chromium.org

Review-Url: https://codereview.chromium.org/2235323003
Cr-Commit-Position: refs/heads/master@{#38610}

BUG=chromium:630386

Review-Url: https://codereview.chromium.org/2240123002
Cr-Commit-Position: refs/heads/master@{#38609}

Decrease regular heap object size to 400k. In a follow up, we can now get rid of
the new space border page while keeping the 1M minimum new space size.

BUG=chromium:636331

This reverts commit 555c9619.

Review-Url: https://codereview.chromium.org/2232653003
Cr-Commit-Position: refs/heads/master@{#38608}

R=mstarzinger@chromium.org
BUG=v8:5265

Review-Url: https://codereview.chromium.org/2240103002
Cr-Commit-Position: refs/heads/master@{#38607}

Review-Url: https://codereview.chromium.org/2221793005
Cr-Commit-Position: refs/heads/master@{#38606}

Revert of [turbofan] Split CodeGenerator::GenerateCode into AssembleCode and FinishCodeObject. (patchset #3 id:40001 of https://codereview.chromium.org/2229243003/ )

Reason for revert:
There is a data race in the initialization of the Isolate::random_number_generator()

Original issue's description:
> [turbofan] Split CodeGenerator::GenerateCode into AssembleCode and FinishCodeObject.
>
> This CL splits CodeGenerator::GenerateCode into two new functions:
> AssembleCode and FinishCodeObject. AssembleCode does not access or
> modify the JS heap, which means that AssembleCode can be executed on
> background threads. FinishCodeObject allocates the generated code object
> on the JS heap and therefore has to be executed on the main thread.
>
> Implementation details:
> The GenerateCode function has been split just before out-of-line code is
> assembled. The reason is that code stubs may be generated when
> out-of-line code is assembled, which potentially allocates these code
> stubs on the heap.
>
> - Parts of initialization of the CodeGenerator has been moved from the
> constructor to an Initialize function so that we can instantiate an empty
> CodeGenerator object in PipelineData.
>
> R=bmeurer@chromium.org, mstarzinger@chromium.org, titzer@chromium.org
>
> Committed: https://crrev.com/03058a2187e32cc4080612181802086527c116a2
> Cr-Commit-Position: refs/heads/master@{#38604}

TBR=bmeurer@chromium.org,mstarzinger@chromium.org,titzer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://codereview.chromium.org/2240523003
Cr-Commit-Position: refs/heads/master@{#38605}

This CL splits CodeGenerator::GenerateCode into two new functions:
AssembleCode and FinishCodeObject. AssembleCode does not access or
modify the JS heap, which means that AssembleCode can be executed on
background threads. FinishCodeObject allocates the generated code object
on the JS heap and therefore has to be executed on the main thread.

Implementation details:
The GenerateCode function has been split just before out-of-line code is
assembled. The reason is that code stubs may be generated when
out-of-line code is assembled, which potentially allocates these code
stubs on the heap.

- Parts of initialization of the CodeGenerator has been moved from the
constructor to an Initialize function so that we can instantiate an empty
CodeGenerator object in PipelineData.

R=bmeurer@chromium.org, mstarzinger@chromium.org, titzer@chromium.org

Review-Url: https://codereview.chromium.org/2229243003
Cr-Commit-Position: refs/heads/master@{#38604}

This adds a very first version of inlined Array.prototype.push into
TurboFan optimized code. The current inlined version has a potential
deopt loop, but it's unlikely that we hit it currently (Crankshaft
suffers from an even worse problem). Once we have a way to learn from
deopts we can fix this deopt loops.

It's also probably overly defensive in when it's safe to inline
the call to Array.prototype.push, but we can always extend that
later once we have sufficient trust in the implementation and see
an actual need to extend it.

BUG=v8:2229,v8:3952,v8:5267
R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2245533003
Cr-Commit-Position: refs/heads/master@{#38603}

R=mstarzinger@chromium.org
BUG=v8:5265

Review-Url: https://codereview.chromium.org/2237423002
Cr-Commit-Position: refs/heads/master@{#38602}

- Change sizes and counts to be size_t on the way.

R=hpayer@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2240603003
Cr-Commit-Position: refs/heads/master@{#38601}

BUG=v8:5193
NOTRY=true

Review-Url: https://codereview.chromium.org/2238193002
Cr-Commit-Position: refs/heads/master@{#38600}

BUG=

Review-Url: https://codereview.chromium.org/2231813003
Cr-Commit-Position: refs/heads/master@{#38599}

BUG=chromium:636368,chromium:635965,chromium:634900

Review-Url: https://codereview.chromium.org/2245483004
Cr-Commit-Position: refs/heads/master@{#38598}

A TransitionElementsKind operation is redundant if we already know that
the object has the target_map (independent of what the source_map might
be).

R=yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2233403003
Cr-Commit-Position: refs/heads/master@{#38597}

Previously, we would both instrument the code, and add/remove
BreakPointInfo objects through BreakLocation. This is bad design and
unsuitable for having two different code kinds.

We would now add/remove BreakPointInfo objects, and use that as source
of truth when instrumenting the code. If we have both bytecode and FCG
code, we would simply apply these break points twice to either.

Notable changes:
- Removed many functionality from BreakLocation.
- Instrumentation (patching code for breaks) happens by applying break
  point info onto code.
- Instrumentation (code patching) is done by the BreakIterator. For
  bytecode, it's BytecodeArrayBreakIterator. For FCG code, it's
  CodeBreakIterator.
- Changes to code instrumentation mostly involves clearing current
  instrumentation and then (re-)applying break points.
- DebugInfo can now reference both bytecode and FCG code.

R=jgruber@chromium.org, mstarzinger@chromium.org
BUG=v8:5265

Review-Url: https://codereview.chromium.org/2238893002
Cr-Commit-Position: refs/heads/master@{#38596}

  port 51e9d5ad (r38577)

  original commit message:
  Use IsPropertyName in VisitObjectLiteral to decide whether to do
  a named property store or call SetProperty.

BUG=

Review-Url: https://codereview.chromium.org/2241693002
Cr-Commit-Position: refs/heads/master@{#38595}

So far we only snapshot the payload data for the deserializer, but
not the data for heap reservation or the code stub keys.

At the same time this change turns some CHECKs that fail in the wild
to DCHECKs. We can try turning them back to CHECKs some other time.

TBR=ahaas@chromium.org
BUG=chromium:636876

Review-Url: https://codereview.chromium.org/2237883002
Cr-Commit-Position: refs/heads/master@{#38594}

An invocation of the ToNumber builtin resulting from lowering the
PlainPrimitiveToNumber cannot have any observable side effects and
thus the builtin call itself is eliminatable.

R=yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2239923004
Cr-Commit-Position: refs/heads/master@{#38593}

Rolling v8/build to 37fd368b5f9d7690eac34cd440275ae323b1dab2

Rolling v8/buildtools to f8fc76ea5ce4a60cda2fa5d7df3d4a62935b3113

Rolling v8/third_party/WebKit/Source/platform/inspector_protocol to 87a50f796882982f6ae1efbd060e4f69467db547

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

Review-Url: https://codereview.chromium.org/2243493006
Cr-Commit-Position: refs/heads/master@{#38592}

Certain token combinations (e.g. number literal followed by semicolon) will
result in a single AST node, but require many levels of recursive descent
parsing to determine this (11 in this example). For some 'obvious'
combinations, we'll simply generate the appropriate AST node fairly far up
in the call tree.

This yields a mild but consistent parser speedup. The main con is code duplication.

[Speedup between 0..20ms in parse time among a set of 25 commonly used sites. Speedup of ~180ms for a site w/ a very large codebase (adwords.google.com). Minor slow-downs between 0..8ms for <20% of sites.]

R=marja@chromium.org
BUG=v8:4947

Review-Url: https://codereview.chromium.org/2188153002
Cr-Commit-Position: refs/heads/master@{#38591}

There's no need to check IsLexicalVariableMode since it's subsumed
by binding_needs_init.

Drive-by change: in VisitVariableLoad, move SetResultInAccumulator
out of switch cases.

BUG=

Review-Url: https://codereview.chromium.org/2232313002
Cr-Commit-Position: refs/heads/master@{#38590}

R=adamk@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2232343002
Cr-Commit-Position: refs/heads/master@{#38589}

BUG=

Review-Url: https://codereview.chromium.org/2230313002
Cr-Commit-Position: refs/heads/master@{#38588}

This target introduces a dependency on WebKit/platform which is not the way we want it.
Keeping the build files in src/inspector, as they are not used and will be useful later on.

BUG=none
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2239603002
Cr-Commit-Position: refs/heads/master@{#38587}

BUG=

Review-Url: https://codereview.chromium.org/2227763004
Cr-Commit-Position: refs/heads/master@{#38586}

This optimization required access to the heap which we can't do off-thread.
There doesn't seem to be a regression without this optmization in anycase,
so just rip it out.

BUG=v8:5203

Review-Url: https://codereview.chromium.org/2238853002
Cr-Commit-Position: refs/heads/master@{#38585}