Ignition does not collect information about lhs and rhs types. It  collects
information about the combined type of lhs, rhs and result types. Since ignition
combines the feedback, sometimes we may collect less precise information than
FCG. This impacts performance of some benchmarks like audio-beat-detection. This
cl tries to mitigate this affect by passing only full-codegen feedback when the
combined FCG feedback is same as the feedback collected by ignition.

BUG=

Review-Url: https://codereview.chromium.org/2488983002
Cr-Commit-Position: refs/heads/master@{#40888}

This changes {FrameState} nodes modeling "after" states to use bytecode
offsets pointing to the deoptimizing bytecode. This is in sync with the
normal execution, as the bytecode offset is advanced after operations
complete in regular bytecode handlers.

The change is necessary to ensure lazy deoptimized frames contain an
accurate bytecode offset while they are on the stack. Such frames can be
inspected by various stack walks. The continuation builtin will advance
the bytecode offset upon return.

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-660379
BUG=chromium:660379

Review-Url: https://codereview.chromium.org/2487173002
Cr-Commit-Position: refs/heads/master@{#40887}

BUG=v8:5614

Review-Url: https://codereview.chromium.org/2492553003
Cr-Commit-Position: refs/heads/master@{#40886}

TurboFan can create ConsStrings with empty first parts (for history on
this decision, see da27e0c8). Add a
fast-path for such cases in String::SlowFlatten.

BUG=

Review-Url: https://codereview.chromium.org/2489273002
Cr-Commit-Position: refs/heads/master@{#40885}

We are removing use of the debugger context. When the debugger triggers
compilation, we may not have a context from which to create a JSArray.

R=ishell@chromium.org

Review-Url: https://codereview.chromium.org/2479123002
Cr-Commit-Position: refs/heads/master@{#40884}

We seem to get some small wins from avoiding the Ldr bytecodes, probably due
to reduced icache pressure since there are less bytecode handlers. Replace
the Ldr bytecodes with Star lookahead inlined into the Lda versions.

Also fixes IsAccumulatorLoadWithoutEffects to include LdaContextSlot and
LdaCurrentContextSlot

BUG=v8:4280

Review-Url: https://codereview.chromium.org/2489513005
Cr-Commit-Position: refs/heads/master@{#40883}

BUG=chromium:663750

Review-Url: https://codereview.chromium.org/2488223002
Cr-Commit-Position: refs/heads/master@{#40882}

With this CL, the bytecode graph builder no longer translates module
loads/stores as runtime calls but in terms of two new JS operators.  These are
lowered in typed-lowering to a sequence of LoadField's.

R=bmeurer@chromium.org
CC=adamk@chromium.org
BUG=v8:1569

Review-Url: https://codereview.chromium.org/2489863003
Cr-Commit-Position: refs/heads/master@{#40881}

BUG=v8:5614

Review-Url: https://codereview.chromium.org/2489933002
Cr-Commit-Position: refs/heads/master@{#40880}

BUG=v8:5614

Review-Url: https://codereview.chromium.org/2490973002
Cr-Commit-Position: refs/heads/master@{#40879}

Also remove the flag scavenge_reclaim_unmodified_objects which has been
defaulted to true for quite some time now.

BUG=chromium:651354

Review-Url: https://codereview.chromium.org/2486173002
Cr-Commit-Position: refs/heads/master@{#40878}

BUG=v8:5530

Review-Url: https://codereview.chromium.org/2480293009
Cr-Commit-Position: refs/heads/master@{#40877}

line_ends is either undefined (if uninitialized) or a fixed array (after
Script::InitLineEnds). All accesses from JS have been removed, therefore
we can skip assigning a COW map and remove the accessor.

Review-Url: https://codereview.chromium.org/2490903002
Cr-Commit-Position: refs/heads/master@{#40876}

This adds information about an exception's caught/uncaught status to the
Runtime.paused event in the data parameter:

{
    "method": "Debugger.paused",
    "params": {
        "callFrames": [
	    [...]
        ],
        "data": {
            "description": "666",
            "type": "number",
            "uncaught": true,  <---
            "value": 666
        },
        "hitBreakpoints": [],
        "reason": "exception"
    }
}

BUG=v8:5530

Review-Url: https://codereview.chromium.org/2488733003
Cr-Commit-Position: refs/heads/master@{#40875}

This cleans up a few Type related TODOs, i.e. removing the now useless
kSmi and kHeapNumber members from TypeCache.

R=yangguo@chromium.org
BUG=v8:5267

Review-Url: https://codereview.chromium.org/2488183002
Cr-Commit-Position: refs/heads/master@{#40874}

Turns out WriteOneByte writes '\0' by default.

BUG=

Review-Url: https://codereview.chromium.org/2494603002
Cr-Commit-Position: refs/heads/master@{#40873}

Previously we created a duplicate map because we couldn't set the
correct ElementsKind when we created the function. This patch updates
the ElementsKind field of the existing map directly instead of
creating a new one.

This patch also correctly sets the instance_size when we create the
map the first time.

Review-Url: https://codereview.chromium.org/2486193003
Cr-Commit-Position: refs/heads/master@{#40872}

When we use unique_ptr on tracing controller and release it to platform,
unique_ptr will crash when we try to start tracing with trace config, this patch
replaces it with raw pointer and delete it explicitly at the end when needed.

TBR=yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2488003002
Cr-Commit-Position: refs/heads/master@{#40871}

- Track representations of virtual registers in InstructionSequence.
- Skip extra aliasing work when no floats or SIMD registers are used.

LOG=N
BUG=v8:4124

Review-Url: https://codereview.chromium.org/2468233004
Cr-Commit-Position: refs/heads/master@{#40870}

... and make them applicable outside of CSA.

Nice bonus is that the assert condition instructions will now appear inside [Assert / ]Assert brackets.

BUG=

Review-Url: https://codereview.chromium.org/2489743002
Cr-Commit-Position: refs/heads/master@{#40869}

Adds an IsInterpreted() function to both SharedFunctionInfo and JSFunction.
This is used to fix the test-heap code-aging tests since Ignition doesn't
age code.

BUG=v8:4680

Review-Url: https://codereview.chromium.org/2481433002
Cr-Commit-Position: refs/heads/master@{#40868}

In tracing we collect runtime statistics data based on top level trace events,
in this patch we force to clear the whole runtime statistics stack when we
enter top level trace events.

Review-Url: https://codereview.chromium.org/2483583002
Cr-Commit-Position: refs/heads/master@{#40867}

With the very same SMIs making up a big chunk
of the parser zone (especially for asm.js) it
makes sense to cache the AstValues for them.
This is not ideal yet, but already saves
hundreds (sic!) MBs of memory for Unity games.

Review-Url: https://codereview.chromium.org/2485423002
Cr-Commit-Position: refs/heads/master@{#40866}

R=titzer@chromium.org
TEST=unittests/WasmModuleVerifyTest.DataSegmentWithImmutableGlobal, unittests/WasmModuleVerifyTest.DataSegmentWithMutableImportedGlobal, unittests/WasmModuleVerifyTest.DataSegmentWithImmutableImportedGlobal

Review-Url: https://codereview.chromium.org/2493433002
Cr-Commit-Position: refs/heads/master@{#40865}

Currently function like "() => 239" contains offset 3 as begin of function and 8 as end of function.
This CL changes this to 6 and 9 respectively.

BUG=chromium:566801
R=yangguo@chromium.org,dgozman@chromium.org
TBR=adamk@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel

Review-Url: https://codereview.chromium.org/2488493003
Cr-Commit-Position: refs/heads/master@{#40864}

Review-Url: https://codereview.chromium.org/2486223002
Cr-Commit-Position: refs/heads/master@{#40863}

Test InstructionSequenceTest has been initialized with a testing RegisterConfiguration
instance defined in instruction-sequence-unittest.h, whereas class ExplicitOperand which
is being tested used RegisterConfiguration from instruction.cc. In case these two
instances are different, the tests would fail. The issue is fixed by using the same
instance of RegisterConfiguration both for test code and code under test.

Additionally, the tests in register-allocator-unittest.cc use hardcoded values
for register and begin failing is the hardcoded register is not available for
allocation. Fix by forcing the use of allocatable registers only.

TEST=unittests.MoveOptimizerTest.RemovesRedundantExplicit,unittests.RegisterAllocatorTest.SpillPhi
BUG=

Review-Url: https://codereview.chromium.org/2433093002
Cr-Commit-Position: refs/heads/master@{#40862}

This adds a new NumberToUint8Clamped simplified operator that does the
round ties to even + clamping necessary to store to Uint8ClampedArrays.

BUG=v8:4470,v8:5267,v8:5615
R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2489563004
Cr-Commit-Position: refs/heads/master@{#40861}

The Ldr[Named/Keyed]Property bytecodes are problematic for the deoptimizer when
inlining accessors in TurboFan. Remove them and replace with a Star lookahead
in the bytecode handlers for Lda[Named/Keyed]Property.

BUG=v8:4280

Review-Url: https://codereview.chromium.org/2485383002
Cr-Commit-Position: refs/heads/master@{#40860}

This stages escape analysis by implying --turbo-escape by the --turbo
flag. It broadens the exposure of the optimization in question.

R=jarin@chromium.org
BUG=v8:4586,v8:5267

Review-Url: https://codereview.chromium.org/1992913005
Cr-Commit-Position: refs/heads/master@{#40859}

We cannot generate debug events if JS execution is disallowed since
vital debugging logic is still implemented in JS. Return early from
Debug::OnException if that is the case.

BUG=chromium:662674

Review-Url: https://codereview.chromium.org/2491443002
Cr-Commit-Position: refs/heads/master@{#40858}

This fixes a race between the sweeper and the array buffer tracker
that causes the sweeper to skip unswept pages.

The scenario:
1. Mark-compact GC adds page p to the sweeping_list_ of the sweeper.
2. GC finishes, the main thread starts executinng JS.
3. The main thread takes p->mutex to unregister an array buffer.
4. A sweeper thread removes p from the sweeping_list_ and tries to
   take p->mutex. The try fails. The sweeper drops p and continues
   to the next page.
5. During selection of evacuation candidate in the next GC we hit
   page->SweepingDone() assert.

BUG=chromium:650314

Review-Url: https://codereview.chromium.org/2484153004
Cr-Commit-Position: refs/heads/master@{#40857}

The bounds check in LoadDataSegment was off by one. I also improved the
error message, and fixed an issue where data was initialized even if
the bounds check failed.

In InstantiateModuleForTesting I allow instantiation of modules without
exports. This check was legacy code from the time where instantiation
and execution was still combined in a single function.

R=titzer@chromium.org, rossberg@chromium.org
TEST=cctest/test-run-wasm-module/InitDataAtTheUpperLimit

Review-Url: https://codereview.chromium.org/2486183002
Cr-Commit-Position: refs/heads/master@{#40856}

Another spec issue.

R=titzer@chromium.org, rossberg@chromium.org
TEST=unittests/WasmModuleVerifyTest.DataWithoutMemory

Review-Url: https://codereview.chromium.org/2486973003
Cr-Commit-Position: refs/heads/master@{#40855}

The problem is that writes to nested objects do not lead to a copy of a referencing VirtualObject, and that each VirtualObjects maintains a cache of an ObjectState node. Together, this leads to inappropriate reuse of ObjectState nodes.
This fix simply always copies all virtual objects when a new VirtualState is created. This is clearly not optimal to avoid clones, but determining precisely which virtual objects are affected by a write is a transitive closure computation on the virtual objects of a virtual state. Alternatively, one could change the semantics of the node cache.

BUG=v8:5611

Review-Url: https://codereview.chromium.org/2488713002
Cr-Commit-Position: refs/heads/master@{#40854}

The distinction didn't provide any benefits.

BUG=chromium:651354

Review-Url: https://codereview.chromium.org/2492433002
Cr-Commit-Position: refs/heads/master@{#40853}

The spec defines that indirect calls in WebAssembly code should cause a
validation error if no function table exists.

The CL contains the following changes:
1) Throw a validation error for indirect calls if the function table
   not exist.
2) Do not create TF nodes to throw a runtime error for indirect calls
   if the function table does not exist.
3) Fix existing unit tests by creating a dummy function table.
4) Add new a new test which tests that indirect calls without function
   table cause a validation error.

R=rossberg@chromium.org
CC=titzer@chromium.org

TEST=unittests/AstDecoderTest.IndirectCallsWithoutTableCrash

Review-Url: https://codereview.chromium.org/2484623002
Cr-Commit-Position: refs/heads/master@{#40852}

If an exception is thrown when there is a Promise being created, the Promise
catch prediction code would call into a part implemented in JavaScript to see if
the Promise has a catch handler. If it is not possible to call back into JS,
e.g., due to a stack overflow, then this would lead to a crash. This patch
"speculates" that, if it's impossible to call back into JavaScript, then the
error is unhandled, avoding the issue. In a future patch, the catch prediction
logic should be entirely written in C++, but this patch adds a minimal fix to
be more friendly to backports.

BUG=chromium:662935
R=jgruber

Review-Url: https://codereview.chromium.org/2487833002
Cr-Commit-Position: refs/heads/master@{#40851}

We recently allowed global constants in asm.js validated code.
When used in a return statement, these need to be of an allowed type.

BUG=660813
R=jpp@chromium.org,aseemgarg@chromium.org

Review-Url: https://codereview.chromium.org/2481103002
Cr-Commit-Position: refs/heads/master@{#40850}

R=bradnelson@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2465103002
Cr-Commit-Position: refs/heads/master@{#40849}