An infinite recursion can be triggered when NoSideEffectToString is
called on an error object with its name property set to itself.
BUG=633998
Review-Url: https://codereview.chromium.org/2206313002
Cr-Commit-Position: refs/heads/master@{#38325}
Thrown exceptions must be handled before another exception is thrown.
This fixes all remaining test failures exposed by not clearing pending
exceptions in JSEntryStub.
BUG=v8:5259
Review-Url: https://codereview.chromium.org/2207923002
Cr-Commit-Position: refs/heads/master@{#38324}
These tests all called assertUnreachable within a try/catch block.
BUG=v8:5246
Review-Url: https://codereview.chromium.org/2209663003
Cr-Commit-Position: refs/heads/master@{#38323}
Moves the creation of SharedFunctionInfo for function literals to the
finalization step. This is required for bytecode generation to be
performed off-thread.
BUG=v8:5203
Review-Url: https://codereview.chromium.org/2179303005
Cr-Commit-Position: refs/heads/master@{#38309}
Avoids compiling baseline code when the function isn't able to be
optimized by crankshaft.
BUG=chromium:632289
Review-Url: https://codereview.chromium.org/2194453002
Cr-Commit-Position: refs/heads/master@{#38304}
Add a new bytecode to create a function context. The handler inlines
FastNewFunctionContextStub.
BUG=v8:4280
LOG=n
Review-Url: https://codereview.chromium.org/2187523002
Cr-Commit-Position: refs/heads/master@{#38301}
This new API function allows for setting several internal fields at once.
By avoiding crossing the API each time for setting an internal property we
can speed up the wrapper creation which has to set two fields for every new
object.
BUG=chromium:630217
Review-Url: https://codereview.chromium.org/2185963002
Cr-Commit-Position: refs/heads/master@{#38299}
So far we treated SignedSmall and Signed32 feedback the same for number
operations. However it would be beneficial to generate (a lot) less code
if we only do a Smi check on the inputs instead of doing the full Smi +
HeapNumber + conversion check that we need to do for Signed32 feedback.
R=epertoso@chromium.org
BUG=v8:4583
Review-Url: https://codereview.chromium.org/2207893002
Cr-Commit-Position: refs/heads/master@{#38290}
In the parser, we desugar yield* with the help of a regular yield. One
particular implementation detail of this desugaring is that when the user calls
the generator's throw method, this throws an exception that we immediately
catch. This exception should not be visible to the user, but through Devtools'
"Pause on Caught Exceptions" feature it used to be.
This CL extends the type of catch predictions with a new value for such internal
exceptions and uses that for the offending try-catch statement in yield*. It
instruments the debugger to _not_ trigger an exception event in that case.
R=yangguo@chromium.orgTBR=littledan@chromium.org
BUG=v8:5218
Review-Url: https://codereview.chromium.org/2203803002
Cr-Commit-Position: refs/heads/master@{#38286}
The MachineOperatorReducer was only reducing word32 expressions of the type x << y | x >>> (32 - y) (and variants) to the equivalent Word32Ror. This CL applies the same pattern-matching logic to Word32Xor.
BUG=
Review-Url: https://codereview.chromium.org/2199323003
Cr-Commit-Position: refs/heads/master@{#38284}
Move all the typing rules for unary and binary number operations to the
OperationTyper and use them for both the regular Typer as well as the
retyper that runs as part of SimplifiedLowering.
R=epertoso@chromium.org
Review-Url: https://codereview.chromium.org/2202883005
Cr-Commit-Position: refs/heads/master@{#38283}
This completely removes the ability from nodes to point directly to the
frame state representing their eager bailout point. All nodes now either
have zero or one frame state inputs. These frame states can by now be
found via checkpoints in the graph.
R=bmeurer@chromium.org
BUG=v8:5021
Review-Url: https://codereview.chromium.org/2020323004
Cr-Commit-Position: refs/heads/master@{#38282}
This removes the frame state input representing the before-state from
nodes having any int32 bitwise operator. Lowering that inserts number
conversions of the inputs has to be disabled when deoptimization is
enabled, because the frame state layout is no longer known.
R=epertoso@chromium.org
BUG=v8:5021,v8:4746
Review-Url: https://codereview.chromium.org/2194383004
Cr-Commit-Position: refs/heads/master@{#38280}
Similarly to how we check whether the entered context has access to the target
context when invoking the function constructor, we should check the involved
contexts before invoking eval().
I forgot to add this in the initial CL that adds the check for the function
constructor. Move the code to a common location, and use it for the GlobalEval
builtin as well.
BUG=chromium:541703
R=verwaest@chromium.org
Review-Url: https://codereview.chromium.org/2199343002
Cr-Commit-Position: refs/heads/master@{#38277}
This was being allowed due to the use of BindingFlags instead of VariableMode
to determine whether a looked-up binding was lexical. Because function
declarations are hoisted, they never need hole checks, and so were being
miscategorized as non-lexical.
This patch augments Context::Lookup with a VariableMode out param, which
allows this check to determine precisely whether the binding is lexical.
BUG=v8:4454, v8:5256
Review-Url: https://codereview.chromium.org/2206483004
Cr-Commit-Position: refs/heads/master@{#38260}
Reason for revert:
Broke Node.js tests (test-require-dot etc.)
Original issue's description:
> Put Scopes into temporary Zone
>
> When parsing a eagerly-parsed-but-lazily-compiled function, we
> used to put some of its AST nodes into a discardable Zone. This
> CL puts the function Scope, its inner Scopes and the related AST
> nodes (Declarations, VariableProxys) into the temporary Zone
> too. This reduces peak memory usage and enables future work to
> keep the temporary Zone around for later compilation.
>
> BUG=
>
> Committed: https://crrev.com/eaebdd858b466057ccc39894a172c9b66868e8f7
> Cr-Commit-Position: refs/heads/master@{#38232}
TBR=adamk@chromium.org,titzer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=
Review-Url: https://codereview.chromium.org/2205013002
Cr-Commit-Position: refs/heads/master@{#38258}
This completely removes translation of exception handler predictions
from the graph IR. We now rely on the runtime using deoptimization
infomation via {FrameSummary} for predictions in optimized code.
R=bmeurer@chromium.org
Review-Url: https://codereview.chromium.org/2207533002
Cr-Commit-Position: refs/heads/master@{#38250}
We cannot just blindly make a representation selection for Phi or Select
based on the truncations, but we also need to consider the type of the
inputs (or actually of the Phi/Select node itself). We can only use
Word32 representation based on Word32 truncation if the inputs are
Number or Oddball, same for Float64.
R=epertoso@chromium.org
BUG=v8:5255
Review-Url: https://codereview.chromium.org/2206553002
Cr-Commit-Position: refs/heads/master@{#38241}
Without this fix, two rules [PASS, MODIFIER] and [FAIL]
would be joined as [PASS, MODIFIER, FAIL], undermining the
intention of the second rule to mark a test as failing.
BUG=v8:4680,v8:4900
Review-Url: https://codereview.chromium.org/2201033002
Cr-Commit-Position: refs/heads/master@{#38238}
This type is not supposed to be constructable by users. Internally, we
use CallSiteUtils::Construct to create CallSite objects; and we simply
map a thrower builtin as the public CallSite constructor.
R=yangguo@chromium.org
BUG=
Review-Url: https://codereview.chromium.org/2201823002
Cr-Commit-Position: refs/heads/master@{#38234}
This makes sure we are not inserting {OsrPoll} instructions for any
statements that are not actually loops and have no back edges. Without
back edges the {BytecodeGraphBuilder} is unable to deduce loop ranges
and hence cannot construct a graph for OSR entry.
R=neis@chromium.org
TEST=mjsunit/regress/regress-5252
BUG=v8:5252
Review-Url: https://codereview.chromium.org/2200733002
Cr-Commit-Position: refs/heads/master@{#38233}
When parsing a eagerly-parsed-but-lazily-compiled function, we
used to put some of its AST nodes into a discardable Zone. This
CL puts the function Scope, its inner Scopes and the related AST
nodes (Declarations, VariableProxys) into the temporary Zone
too. This reduces peak memory usage and enables future work to
keep the temporary Zone around for later compilation.
BUG=
Review-Url: https://codereview.chromium.org/2193793002
Cr-Commit-Position: refs/heads/master@{#38232}
When we narrow a signed32 comparison to uint8 or uint16 representation,
we also need to change the condition to unsigned comparisons otherwise
the comparison will be done on int16/int8 which interprets the narrowed
bits wrong.
R=epertoso@chromium.org
BUG=v8:5254
Review-Url: https://codereview.chromium.org/2202803003
Cr-Commit-Position: refs/heads/master@{#38231}
introduced in https://crrev.com/72f884a19fa4434bba6fc0e013ec4ea0a2366893
The regression comes from adding the next weak field of AllocationSite
as a hidden reference into the snapshot.
Before 72f884 the reference was implicitly ignored because the body
descriptor of AllocationSite did not include it.
This patch explicitly skip the next weak field of AllocationSite.
BUG=chromium:630027
Review-Url: https://codereview.chromium.org/2189643004
Cr-Commit-Position: refs/heads/master@{#38211}
This switches our inlining tests (i.e. cctest/test-run-inlining) to rely
on global object instead of function context specialization, which is
more in sync with what we are actually shipping. It will also allow us
to test inlining with the BytecodeGraphBuilder without having to add
support for function context specialization just for testing purposes.
R=bmeurer@chromium.org
TEST=cctest/test-run-inlining
BUG=v8:5251
Review-Url: https://codereview.chromium.org/2200673002
Cr-Commit-Position: refs/heads/master@{#38209}
The flag was introduced for ignition development. It can only
be used when running ignition tests in isolation on the bots.
The bots only use ignition_turbo in isolation since a while
and don't pass the --ignition flag anymore.
BUG=v8:5238
Review-Url: https://codereview.chromium.org/2197123002
Cr-Commit-Position: refs/heads/master@{#38206}
First step of deprecating the dedicated ignition alias.
Next it will be changed on the bots to use the bot_default
suite. Then we'll delete it.
BUG=v8:5238
Review-Url: https://codereview.chromium.org/2194153002
Cr-Commit-Position: refs/heads/master@{#38202}
This CL fixes a long-standing bug with Object.keys where the enumerability
check was omitted if the [ownKeys] trap is not present. The only distinction the
KeyAccumulator needs is whether it collects keys for for-in (is_for_in_) or not.
ForInFilter performs a separate step to filter out non-enumerable keys later-on
while in all the other use-cases we have to filter keys.
BUG=v8:1543, v8:5250
Review-Url: https://codereview.chromium.org/2176113009
Cr-Commit-Position: refs/heads/master@{#38199}
This removes the frame state input representing the before-state from
nodes having any shift operator. Any lowering that woult insert number
conversions of the inputs has already been disabled when deoptimization
is enabled, because the frame state layout is no longer known.
R=epertoso@chromium.org
BUG=v8:5021
Review-Url: https://codereview.chromium.org/2190743003
Cr-Commit-Position: refs/heads/master@{#38194}
This introduces a bunch of new tests that test various aspects of
accessor inlining in TurboFan (without the actual inlining), and does
the appropriate fixes to the AstGraphBuilder. The actual inlining CL
will land separately (so we don't need to revert the tests and fixes
if the accessor CL has to be reverted).
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2197913002
Cr-Commit-Position: refs/heads/master@{#38191}
This gets rid of the Star bytecodes that were always dispatched to from
ToObject.
ToObject now outputs to register instead of to the accumulator and
ForInPrepare gets the receiver object from an input register.
BUG=v8:4820
LOG=n
Review-Url: https://codereview.chromium.org/2189463006
Cr-Commit-Position: refs/heads/master@{#38177}
Drive-by fix: actually match the hint in the IsSpeculativeBinopMatcher.
Review-Url: https://codereview.chromium.org/2191883002
Cr-Commit-Position: refs/heads/master@{#38176}
The test was calling OptimizeFunctionOnNextCall on a function before
ever executing it - crankshaft therefore didn't have any type info and
was generating a soft deoptimization bailout. Make sure we execute the
function before calling OptimizeFunctionOnNextCall to avoid this issue.
BUG=
Review-Url: https://codereview.chromium.org/2168603003
Cr-Commit-Position: refs/heads/master@{#38171}
This adds preliminary support for on-stack replacement from Ignition to
optimized code generated by TurboFan to the runtime profiler. Involved
heuristics (e.g. code size allowance) have been taken from existing code
without any re-evaluation in the new setting.
R=rmcilroy@chromium.org
BUG=v8:4764
Review-Url: https://codereview.chromium.org/2182183005
Cr-Commit-Position: refs/heads/master@{#38159}
Previously, the stack property was set up in JS as read-only; but since
it had a JS setter, writability was ignored and writing to stack was
possible.
This is no longer the case now that stack is either an actual data
property, or is associated with C++ accessors. Explicitly set the
property as writable to preserve old behavior.
BUG=5245
R=yangguo@chromium.org
Review-Url: https://codereview.chromium.org/2190313002
Cr-Commit-Position: refs/heads/master@{#38158}
In contrast to the generic stream, this character stream works without
accessing the heap, and can be used on a background thread.
BUG=v8:5215
R=vogelheim@chromium.org,marja@chromium.org
Review-Url: https://codereview.chromium.org/2184393002
Cr-Commit-Position: refs/heads/master@{#38154}
This CL introduces a new fast flat instantiations cache for the first 1024 object templates.
After that we fall back to the existing slower dictionary cache.
Drive-by-fix: de-handlify and clean up some code in api-natives.cc
BUG=chromium:630217
Review-Url: https://codereview.chromium.org/2170743003
Cr-Commit-Position: refs/heads/master@{#38146}
In the process also inline the stub into the appropriate interpreter bytecode
handler and make sure that the context register is preserved in hand-written
assembly code that calls the stub and expects the context register to be
preserved.
BUG=608675
Review-Url: https://codereview.chromium.org/2188993003
Cr-Commit-Position: refs/heads/master@{#38132}
Reason for revert:
Still crashing.
Original issue's description:
> [heap] Reland "Remove black pages and use black areas instead."
>
> BUG=chromium:630969,chromium:630386
> LOG=n
>
> Committed: https://crrev.com/9e37a07c8de0a20ef2681e26824ff4d329102603
> Cr-Commit-Position: refs/heads/master@{#38057}
TBR=ulan@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:630969,chromium:630386
Review-Url: https://codereview.chromium.org/2183383004
Cr-Commit-Position: refs/heads/master@{#38129}
This adds the build target inspector_protocol_parser_test, which depends
on several more inspector protocol related targets. The resulting
gtest executable runs, but has failures that have to be fixed.
GN build configuration will follow.
A copy of v8-inspector/js_protocol.json has been included to be able to
use it before the actual migration.
BUG=chromium:580337
Review-Url: https://codereview.chromium.org/2184733002
Cr-Commit-Position: refs/heads/master@{#38111}
This patch updates internal data structures used by V8 to support
multiple indirect function tables (WebAssembly/design#682). But, since
this feature is post-MVP, the functionality is not directly exposed and
parsing/generation of WebAssembly is left unchanged. Nevertheless, it
is being used in an experiment to implement fine-grained control flow
integrity based on C/C++ types.
BUG=
Review-Url: https://codereview.chromium.org/2174123002
Cr-Commit-Position: refs/heads/master@{#38110}
Remove TODO to perform same optimization as AstGraphBuilder.
When visiting for effect in a postfix count operation, don't
keep the intermediate result of ToNumber.
BUG=v4:4280
LOG=n
Review-Url: https://codereview.chromium.org/2187823002
Cr-Commit-Position: refs/heads/master@{#38101}
All supported ARM targets support unaligned accesses for integer
accesses. This patch removes the remnants of support for older targets.
BUG=v8:5077
Review-Url: https://codereview.chromium.org/2184823002
Cr-Commit-Position: refs/heads/master@{#38099}
Objects that reside below the age mark could be on pages that have been moved
within new space. In this case mementos survived which can actually point to
already-collected allocation sites.
BUG=chromium:631050,chromium:581412
R=hpayer@chromium.org
Review-Url: https://codereview.chromium.org/2179033005
Cr-Commit-Position: refs/heads/master@{#38094}
This leads to a better handling of the Smi case when we introduce a checked truncation from a number or oddbal to a 32 bit word, which we were previously doing by concatenating a Smi to float64 conversion with a float64 to word32 truncation.
BUG=
Review-Url: https://codereview.chromium.org/2191503002
Cr-Commit-Position: refs/heads/master@{#38091}
This required the introduction of the CheckedNumberOrOddballAsWord32 use info, and a change in the RepresentationChanger to handle it.
BUG=
Review-Url: https://codereview.chromium.org/2184513003
Cr-Commit-Position: refs/heads/master@{#38086}
Reason for revert:
Revert this CL due to V8 Arm Builder failure and V8 Mips Builder failure.
https://build.chromium.org/p/client.v8.ports/builders/V8%20Arm%20-%20builder/builds/2456https://build.chromium.org/p/client.v8.ports/builders/V8%20Mips%20-%20builder/builds/2506
Original issue's description:
> [Tracing] V8 Tracing Controller
>
> V8 has had a trace event macro interface for while, but without a tracing
> controller a standalone V8 would be unable to collect traces.
>
> This CL introduces a complete Tracing Controller system for V8.
> It is fully function except that it does not yet store trace event args.
>
> This CL has a few components,
> The tracing controller itself, contributed by the author of this CL
> The Trace config (including the parser), contributed by lpy@
> The Trace Object, Trace Writer, and Trace Buffer are all contributed by rksang@
>
> BUG=v8:4561
> LOG=N
>
> Committed: https://crrev.com/3d598452679ce208ad9b2f48e0fb3fae352ce375
> Cr-Commit-Position: refs/heads/master@{#38073}
TBR=jochen@chromium.org,mattloring@google.com,rskang@google.com,yangguo@chromium.org,fmeawad@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4561
Review-Url: https://codereview.chromium.org/2183943002
Cr-Commit-Position: refs/heads/master@{#38074}
V8 has had a trace event macro interface for while, but without a tracing
controller a standalone V8 would be unable to collect traces.
This CL introduces a complete Tracing Controller system for V8.
It is fully function except that it does not yet store trace event args.
This CL has a few components,
The tracing controller itself, contributed by the author of this CL
The Trace config (including the parser), contributed by lpy@
The Trace Object, Trace Writer, and Trace Buffer are all contributed by rksang@
BUG=v8:4561
LOG=N
Review-Url: https://codereview.chromium.org/2137013006
Cr-Commit-Position: refs/heads/master@{#38073}
Port 580fdf3c05
This also reverses the MachineType stored for partial unaligned access support
such that it records the unsupported types, rather than supported types.
BUG=
Review-Url: https://codereview.chromium.org/2182493003
Cr-Commit-Position: refs/heads/master@{#38065}
This is a first step towards a perfect world where a call interface descriptor is the only place that defines calling convention for a particular code stub.
Review-Url: https://codereview.chromium.org/2172223002
Cr-Commit-Position: refs/heads/master@{#38059}
Reason for revert:
Fix has been landed.
Original issue's description:
> Revert of [interpreter] Add explicit OSR polling bytecode. (patchset #6 id:100001 of https://codereview.chromium.org/2172233002/ )
>
> Reason for revert:
> Bunch of breakages. Maybe bad interaction with e520e5da55 ?
>
> E.g.:
> https://build.chromium.org/p/client.v8/builders/V8%20Linux64/builds/11607
>
> Original issue's description:
> > [interpreter] Add explicit OSR polling bytecode.
> >
> > This adds an explicit {OsrPoll} bytecode into every loop header which
> > triggers on-stack replacement when armed. Note that each such bytecode
> > stores the static loop depths as an operand, and hence can be armed for
> > specific loop depths.
> >
> > This also adds builtin code that triggers OSR compilation and switches
> > execution over to optimized code in case compilation succeeds. In case
> > compilation fails, the bytecode dispatch just continues unhindered.
> >
> > R=rmcilroy@chromium.org
> > TEST=mjsunit/ignition/osr-from-bytecode
> > BUG=v8:4764
> >
> > Committed: https://crrev.com/a55beb68e0ededb3773affa294a71edc50621458
> > Cr-Commit-Position: refs/heads/master@{#38043}
>
> TBR=rmcilroy@chromium.org,mstarzinger@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=v8:4764
>
> Committed: https://crrev.com/439aa2c6d708bfd95db725bd6f97c4c49bbc51fc
> Cr-Commit-Position: refs/heads/master@{#38044}
TBR=rmcilroy@chromium.org,machenbach@chromium.org
BUG=v8:4764
Review-Url: https://codereview.chromium.org/2184713002
Cr-Commit-Position: refs/heads/master@{#38056}
The bug was caused when validating expressions
X >> 0
for indexing into 8-bit heap views. If X was not an intish, the 'normal'
validation path would fail. That, however, left the type of X registered
in the AsmTyper::node_types_ member.
Later, in the 'lenient' code path for 8-bit views, the entire X >> 0
expression would be validated, which would cause X to be validated
again, at which point AsmTyper::SetTypeOf() would DCHECK because the
supplied node already had a type associated with it.
The fix was to simply FAIL() when X is not an intish. This is safe
because if X is not an intish, then
Validate(>>, !intish, FixNum)
will also fail.
BUG= https://bugs.chromium.org/p/chromium/issues/detail?id=628803
BUG= https://bugs.chromium.org/p/v8/issues/detail?id=4203
TEST= cctest/asmjs/test-asm-typer.cc
LOG= N
Review-Url: https://codereview.chromium.org/2181723002
Cr-Commit-Position: refs/heads/master@{#38053}
This allows us to fuse the address computation with the actual memory
access operation on x64, which reduces the register pressure and the
number of instructions. There's probably some follow up cleanup that has
to happen to make sure the machine operator optimizations that are
relevant to word64 computations are also available (similar to what is
already available for word32).
R=epertoso@chromium.org
Review-Url: https://codereview.chromium.org/2183043002
Cr-Commit-Position: refs/heads/master@{#38051}
Reason for revert:
Bunch of breakages. Maybe bad interaction with e520e5da55 ?
E.g.:
https://build.chromium.org/p/client.v8/builders/V8%20Linux64/builds/11607
Original issue's description:
> [interpreter] Add explicit OSR polling bytecode.
>
> This adds an explicit {OsrPoll} bytecode into every loop header which
> triggers on-stack replacement when armed. Note that each such bytecode
> stores the static loop depths as an operand, and hence can be armed for
> specific loop depths.
>
> This also adds builtin code that triggers OSR compilation and switches
> execution over to optimized code in case compilation succeeds. In case
> compilation fails, the bytecode dispatch just continues unhindered.
>
> R=rmcilroy@chromium.org
> TEST=mjsunit/ignition/osr-from-bytecode
> BUG=v8:4764
>
> Committed: https://crrev.com/a55beb68e0ededb3773affa294a71edc50621458
> Cr-Commit-Position: refs/heads/master@{#38043}
TBR=rmcilroy@chromium.org,mstarzinger@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4764
Review-Url: https://codereview.chromium.org/2184553003
Cr-Commit-Position: refs/heads/master@{#38044}
This adds an explicit {OsrPoll} bytecode into every loop header which
triggers on-stack replacement when armed. Note that each such bytecode
stores the static loop depths as an operand, and hence can be armed for
specific loop depths.
This also adds builtin code that triggers OSR compilation and switches
execution over to optimized code in case compilation succeeds. In case
compilation fails, the bytecode dispatch just continues unhindered.
R=rmcilroy@chromium.org
TEST=mjsunit/ignition/osr-from-bytecode
BUG=v8:4764
Review-Url: https://codereview.chromium.org/2172233002
Cr-Commit-Position: refs/heads/master@{#38043}
When we eliminate nodes during truncation analysis that have no value
uses, we must make sure that we do not eliminate speculative number
operations that would have side effects depending on the inputs, i.e.
for example a SpeculativeNumberMultiply(x,y) does ToNumber(x) and
ToNumber(y) first, so if either x or y could throw an exception during
ToNumber conversion, we must not eliminate the multiplication, even if
it has no value uses (some later pass may kill the actual machine
multiplication, but the checks on the inputs have to remain still).
So we check whether both x and y are PlainPrimitive, i.e. neither
Receiver nor Symbol, which could raise exceptions for ToNumber, and
only in that case we propagate the "unusedness" of the node to its
inputs.
This also uncovered a bug with the type of Dead, which must be None,
as this represents an impossible value, so we had to fix that too.
Also the dead code removal will not work correctly for constants (i.e.
pure nodes with no value inputs), as those might be cached and hence
we might resurrect them for an unrelated node lowering during
SimplifiedLowering and only later kill the actual node (replacing its
uses with Dead), which would then also replace the new use with Dead.
So that was fixed as well. This shouldn't change anything for the
result, as unused constants automagically disappear from the graph later
on anyways.
R=yangguo@chromium.org
BUG=chromium:631318
Review-Url: https://codereview.chromium.org/2182003002
Cr-Commit-Position: refs/heads/master@{#38038}
This slightly simplifies scope handling. It also makes it possible to
implement some potential future changes to classes purely in the parser
by adding additional code to the DoExpression.
This is a portion of https://codereview.chromium.org/2142333002/, which
probably isn't going through in full.
Review-Url: https://codereview.chromium.org/2176653003
Cr-Commit-Position: refs/heads/master@{#38035}
The testcase allocates JSArraybuffer on 2 separate pages which should be
on the New space. In the testcase semi space size is set to 2MB.
Since page size on PPC is 4MB the semi new space size defaults to 4MB.
Therefore when allocating 2nd buffer, scavenge GC kicks in as from-space is
filled up and copies 1st buffer to to-space. Now, the 2nd buffer also gets
allocated on the same to-space, therefore both buffer end up being on the
same page. This fix should allocate enough semi new space to contain 2
pages (for all platform).
The testcase was added as part of https://codereview.chromium.org/2036643002R=mlippautz@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com
BUG=
LOG=N
Review-Url: https://codereview.chromium.org/2167853002
Cr-Commit-Position: refs/heads/master@{#38028}
Failure is due to different endianness on big endian. The test now passes on
both big-endian and little-endian architectures.
TEST=cctest/test-code-stubs-mips64/ConvertDToI
BUG=
Review-Url: https://codereview.chromium.org/2157373002
Cr-Commit-Position: refs/heads/master@{#38022}
ToName was always generated with a subsequent Star, fuse them.
Requires a few changes in the peephole optimizer as ToName cannot be
elided as easily, but must be replaced by Star.
BUG=v8:4280
LOG=n
Review-Url: https://codereview.chromium.org/2169813002
Cr-Commit-Position: refs/heads/master@{#38019}
After multiplying two integers we emit code like:
if (result == 0) {
if (OR_OPERATION(rhs, lhs) < 0) {
DEOPT;
}
}
This CL allows us to eliminate the OR and comparison if either rhs or
lhs is a negative number, reducing the code to:
if (result == 0) DEOPT;
BUG=
Review-Url: https://codereview.chromium.org/2167643002
Cr-Commit-Position: refs/heads/master@{#38016}
Turn the LoadElimination into a proper graph Reducer so that it can run
together with ValueNumbering and RedundancyElimination to a fixpoint
for maximum load/check elimination. This also adds initial support for
eliminating redundant LoadElement/StoreElement nodes.
BUG=v8:4930,v8:5141
Review-Url: https://codereview.chromium.org/2164253002
Cr-Commit-Position: refs/heads/master@{#38015}
Move the logic for allocating the global declaration pair array
from VisitDeclarations to a later step. This is required for
concurrent bytecode generation.
This change requires adding support for reserving fixed
constant pool array entries, which can be later updated
with the value of the literal.
BUG=v8:5203
Review-Url: https://codereview.chromium.org/2167763003
Cr-Commit-Position: refs/heads/master@{#38010}
Introducing machine operators early causes trouble for the typing,
truncation analysis and representation selection, so we should rather
stick to simplified operators instead. Now there's only the for-in case
left, which is not clear how we can handle this in a better way.
Drive-by-fix: Also don't introduce Int32Constant and Word32Shl in
JSTypedLowering, but use NumberConstant and proper NumberShiftLeft
operators instead.
R=jarin@chromium.org
BUG=chromium:630951
Review-Url: https://codereview.chromium.org/2182453002
Cr-Commit-Position: refs/heads/master@{#38008}
Reason for revert:
Suspected to cause crbug.com/630969
Original issue's description:
> [heap] Remove black pages and use black areas instead.
>
> BUG=630386
> LOG=n
>
> Committed: https://crrev.com/b008a0d5a3db80a854cb93d9c94d67bf2d780f2c
> Cr-Commit-Position: refs/heads/master@{#37967}
TBR=ulan@chromium.org,hpayer@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=630386
Review-Url: https://codereview.chromium.org/2176133002
Cr-Commit-Position: refs/heads/master@{#38006}
Always use the BytecodeGraphBuilder when the --turbo-from-bytecode
is enabled, assuming the function should be compiled for Ignition.
Adds a new MaybeOptimizeIgnition function to runtime-profiler
which is called if the function should be optimized from bytecode
rather than going via full-codegen.
BUG=v8:4280
Committed: https://crrev.com/9ca7db914be88e6792a88eab4a1988ee031d70c4
Review-Url: https://codereview.chromium.org/2156753002
Cr-Original-Commit-Position: refs/heads/master@{#37921}
Cr-Commit-Position: refs/heads/master@{#38002}
Skip test-run-load-store/RunUnalignedLoadStoreUnalignedAccess on ARM until
UnalignedLoad and UnalignedStore operators get implemented
NOTRY=true
Review-Url: https://codereview.chromium.org/2182433002
Cr-Commit-Position: refs/heads/master@{#38001}
The dead code elimination in SimplifiedLowering can eliminate pure nodes
if they don't have value uses. But some of those can indeed have control
inputs, i.e. Phi nodes do of course have a control input.
R=jarin@chromium.org
BUG=chromium:630923
Review-Url: https://codereview.chromium.org/2177133002
Cr-Commit-Position: refs/heads/master@{#37995}
In PrependElementIndicesImpl we sort a FixedArray of indices potentially
containing HeapNumbers. During the string conversion we might trigger a GC.
This in turn might try to read a slot where we previously had a HeapNumber
but the sort sneaked a SMI in there which is not a valid pointer.
BUG=chromium:630561
Review-Url: https://codereview.chromium.org/2173653003
Cr-Commit-Position: refs/heads/master@{#37993}
The uses_arguments() bool is not needed for correct
behavior, since that same information is available after scope analysis
based on whether we allocated the Scope::arguments_ var.
BUG=v8:5209
Review-Url: https://codereview.chromium.org/2168293002
Cr-Commit-Position: refs/heads/master@{#37990}
Implement UnalignedLoad and UnalignedStore optional
turbofan operators and use them in WasmCompiler for unaligned
memory access.
BUG=
Review-Url: https://codereview.chromium.org/2122853002
Cr-Commit-Position: refs/heads/master@{#37988}
TC-39 recently decided to remove the Python-based testing harness from the
Test262 project [1]. The code has been duplicated in a standalone project;
update V8's dependencies to fetch from that new location. This is based on
an earlier patch by Mike Pennisi.
[1] 2b9722db9b/es7/2016-05/may-25.md
BUG=v8:5078
Review-Url: https://codereview.chromium.org/2131743002
Cr-Commit-Position: refs/heads/master@{#37985}
ToNumber's result is always directly stored to a register using a Star
bytecode. Fuse it into ToNumber.
BUG=v8:4280
LOG=n
Review-Url: https://codereview.chromium.org/2165953002
Cr-Commit-Position: refs/heads/master@{#37976}
So far we don't have a useful way to inline Math.max or Math.min in
TurboFan optimized code. This adds new operators NumberMax and NumberMin
and changes the Float64Max/Float64Min operators to have JavaScript
semantics instead of the C++ semantics that it had previously.
This also removes support for recognizing the tenary case in the
CommonOperatorReducer, since that doesn't seem to have any positive
impact (and actually doesn't show up in regular JavaScript, where
people use Math.max/Math.min instead).
Drive-by-fix: Also nuke the unused Float32Max/Float32Min operators.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2170343002
Cr-Commit-Position: refs/heads/master@{#37971}
This allows us to skip complicated logic for setting the accessors.
BUG=
Review-Url: https://codereview.chromium.org/2164903004
Cr-Commit-Position: refs/heads/master@{#37969}
This is in preparation to implementing exception prediction for async
functions. Each handler table entry can now predict "caught", "uncaught", or
"promise". The latter indicates that the exception will lead to a promise
rejection.
To mark the relevant try-catch blocks, we add a new native syntax.
try { } %catch (e) { } indicates a TryCatchStatement with the "promise"
prediction.
The previous implementation of using the function to tell the relevant
try-catch apart from inner try-catch blocks will not work for async functions
since these can have inner try-catch blocks inside the same function.
BUG=v8:5167
Review-Url: https://codereview.chromium.org/2161263003
Cr-Commit-Position: refs/heads/master@{#37966}
See discussion in https://codereview.chromium.org/2156303002/#msg8
With the new --harmony-function-tostring behavior, these tests would
fail without this change. This change makes the tests pass regardless
of whether or not --harmony-function-tostring is used.
All of these changes are simply inserting a space after the "function"
keyword to match the current function toString behavior. When
--harmony-function-tostring is enabled, the toString behavior matches
the spacing used in the function declaration. With the declaration
matching the current formatting, the toString behavior becomes
unaffected by --harmony-function-tostring.
BUG=v8:4958
LOG=n
Review-Url: https://codereview.chromium.org/2161413002
Cr-Commit-Position: refs/heads/master@{#37959}
This cl also fixes two bugs in the previous code:
1) JITed functions were not allowed access to the heap because the module instance wasn't correctly synthesized. This wasn't discovered in the previous test.
2) Decoding of functions with the JITSingleFunction opcode was off by 1 as the length of the opcode wasn't computed correctly.
BUG=5044
Review-Url: https://codereview.chromium.org/2168183002
Cr-Commit-Position: refs/heads/master@{#37957}
Replace the zonelist with a link from a scope to any of its inner scopes, and a link to any sibling scope.
This makes scopes that track inner scopes use roughly the same amount of space as previously scopes without inner scopes would use for the empty zonelist (pointer to the memory + length field, which, granted could be slightly smaller on 64bit).
BUG=v8:5209
Review-Url: https://codereview.chromium.org/2162143005
Cr-Commit-Position: refs/heads/master@{#37941}
Use the ForInFilterStub directly. Hence we will only jump to the runtime for
special receivers (instance_type <= LAST_SPECIAL_RECEIVER_TYPE) and for
converting element indices which are not in the string cache.
BUG=
Review-Url: https://codereview.chromium.org/2151773002
Cr-Commit-Position: refs/heads/master@{#37934}
Move VisitLiteral to decide what type of literal is being emitted by
checking the raw ASTValue type, instead of the internalized on-heap
value. This is required for concurrent bytecode generation.
As part of this change, the NUMBER AstValue constructor is modified to
try to convert numbers without a dot to SMIs where possible. This is to
maintain the behavior in NewNumber where such numbers are internalized as
SMIs, and ensures that we still emit LdaSmi bytecodes for these values
in the generated bytecode.
BUG=v8:5203
Review-Url: https://codereview.chromium.org/2152853002
Cr-Commit-Position: refs/heads/master@{#37931}
This removes a duplicate control scope. The visitor for ForOfStatement
nodes in the AST uses VisitIterationBody which pushes a separate control
scope. The number of control scopes will be off when we use them for
tracking loop depths.
R=rmcilroy@chromium.org
Review-Url: https://codereview.chromium.org/2164503005
Cr-Commit-Position: refs/heads/master@{#37930}
Reason for revert:
Breaks tsan:
https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20TSAN/builds/10758
Original issue's description:
> [Intepreter] Always use BytecodeGraphBuilder when --turbo-from-bytecode
>
> Always use the BytecodeGraphBuilder when the --turbo-from-bytecode
> is enabled, assuming the function should be compiled for Ignition.
> Adds a new MaybeOptimizeIgnition function to runtime-profiler
> which is called if the function should be optimized from bytecode
> rather than going via full-codegen.
>
> BUG=v8:4280
>
> Committed: https://crrev.com/9ca7db914be88e6792a88eab4a1988ee031d70c4
> Cr-Commit-Position: refs/heads/master@{#37921}
TBR=mstarzinger@chromium.org,rmcilroy@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2165223002
Cr-Commit-Position: refs/heads/master@{#37925}
Always use the BytecodeGraphBuilder when the --turbo-from-bytecode
is enabled, assuming the function should be compiled for Ignition.
Adds a new MaybeOptimizeIgnition function to runtime-profiler
which is called if the function should be optimized from bytecode
rather than going via full-codegen.
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2156753002
Cr-Commit-Position: refs/heads/master@{#37921}
The optimizing compilers actually invoke %TransitionElementsKind for
any kind of JSObject, the only relevant thing is the elements kind.
The runtime function was however checking for JSArray unnecessarily.
This only worked by coincindence in Crankshaft because the stub would
normally not call into the runtime fallback.
R=jarin@chromium.org
BUG=chromium:629823
Review-Url: https://codereview.chromium.org/2166963004
Cr-Commit-Position: refs/heads/master@{#37919}
Fixes bug in test-gap-resolver.cc that didn't test different move reps.
Fixes test canonicalization so all slots have the same type (non-float).
Improve test failure text output.
LOG=N
BUG=v8:5187
Review-Url: https://codereview.chromium.org/2169493002
Cr-Commit-Position: refs/heads/master@{#37915}
This CL more or less reverts commit https://codereview.chromium.org/2107733002/
The use of the MathPow code stub that was introduced by that commit caused
problems on arm64, and the MathPow code stub was also an obstacle in the
implementation of parallel code generation.
In addition this CL turns on the mjsunit/wasm/embenchen tests for arm64
which were turned off because of problems with MathPow on arm64.
R=titzer@chromium.org, bradnelson@chromium.org
Review-Url: https://codereview.chromium.org/2166793002
Cr-Commit-Position: refs/heads/master@{#37911}
This CL fixes weird performance implications when changing layout of Code::flags field:
it happened that the unused ICStateField with MONOMORPHIC value in the handlers' flags
was accidentally offsetting the underflow bug in stub cache probing code on arm, arm64,
mips and mips64.
Stub cache tests now work even when snapshot is enabled.
Drive-by-change: Fixed counters manipulation on arm64 and mips64.
BUG=chromium:618701
Review-Url: https://codereview.chromium.org/2161153002
Cr-Commit-Position: refs/heads/master@{#37910}
For some bytecodes it is beneficial to always look for a Star
bytecode when dispatching to the next and inline perform it
without dispatching to the Star handler.
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/2142273003
Cr-Commit-Position: refs/heads/master@{#37904}
This additionally makes the invariant obvious that outer_scope==nullptr+is_with_scope is impossible.
BUG=v8:5209
Review-Url: https://codereview.chromium.org/2165923002
Cr-Commit-Position: refs/heads/master@{#37902}
As required by the spec.
This is a variant of what I reverted in f47e722403.
It will probably still cause a regression but now it's easier to migrate (parts of)
the current implementation to C++, which is expected to make things faster again.
BUG=chromium:627729,v8:5113
Review-Url: https://codereview.chromium.org/2164923002
Cr-Commit-Position: refs/heads/master@{#37897}
This avoids implementation-defined signed overflow in the simulator's
AddWithCarry implementation. The implementation of AddWithCarry now uses
unsigned arithmetic exclusively.
Testing coverage is also significantly improved.
BUG=
Review-Url: https://codereview.chromium.org/2157283003
Cr-Commit-Position: refs/heads/master@{#37895}
This frees up a field in Scope and untangles scope a little from the parser.
BUG=v8:5209
Review-Url: https://codereview.chromium.org/2160943004
Cr-Commit-Position: refs/heads/master@{#37887}
Add a dedicated simplified operator to inline the general case for the
ToBoolean conversion. In a follow up CL we will also use the ToBoolean
hints gathered by the baseline compiler.
Review-Url: https://codereview.chromium.org/2167593002
Cr-Commit-Position: refs/heads/master@{#37882}
Reason for revert:
This cl causes a large regression in octane (https://chromeperf.appspot.com/group_report?bug_id=629503). I have to investigate the reason before I can reland this.
Original issue's description:
> [Interpreter] Collect type feedback for 'new' in the bytecode handler
>
> Collect type feedback in the bytecode handler for 'new' bytecode. The
> current implementation does not collect allocation site feedback.
>
> BUG=v8:4280, v8:4780
> LOG=N
>
> Committed: https://crrev.com/1eadc76419b323fb2e55ae9953142f801704aa59
> Cr-Commit-Position: refs/heads/master@{#37862}
TBR=rmcilroy@chromium.org,bmeurer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4280, v8:4780
Review-Url: https://codereview.chromium.org/2165633003
Cr-Commit-Position: refs/heads/master@{#37872}
This ports a large portion of Error methods to C++,
including the constructor, stack setter and getter,
and Error.prototype.toString.
BUG=
Review-Url: https://codereview.chromium.org/2142933003
Cr-Commit-Position: refs/heads/master@{#37870}
Original issue's description:
> [interpeter] Move to table based peephole optimizer.
>
> Introduces a lookup table for peephole optimizations.
>
> Fixes some tests using BytecodePeepholeOptimizer::Write() that should
> have been update to use BytecodePeepholeOptimizer::WriteJump().
>
> BUG=v8:4280
> LOG=N
>
> Committed: https://crrev.com/f4234422b93b21a286b0f31799009bcbe8b90b9e
> Cr-Commit-Position: refs/heads/master@{#37819}
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/2164583002
Cr-Commit-Position: refs/heads/master@{#37866}
Collect type feedback in the bytecode handler for 'new' bytecode. The
current implementation does not collect allocation site feedback.
BUG=v8:4280, v8:4780
LOG=N
Review-Url: https://codereview.chromium.org/2153433002
Cr-Commit-Position: refs/heads/master@{#37862}
This allows to pass deoptimization reasons to the profiler without the
requirement of always providing a source position. The absence of deopt
reasons is now communicated via a sentinel as the deopt id value. The
deoptimization reasons recently added to TurboFan are now passed to the
profiler.
R=bmeurer@chromium.org
TEST=cctest/test-cpu-profiler
Review-Url: https://codereview.chromium.org/2159793002
Cr-Commit-Position: refs/heads/master@{#37852}
We need to pay attention to potential side effects from parameter
evaluation when inlining the fast case Array.prototype.shift.
R=yangguo@chromium.org
BUG=chromium:614644
Review-Url: https://codereview.chromium.org/2161943002
Cr-Commit-Position: refs/heads/master@{#37850}
Original issue's description:
> Don't compile functions in a context the caller doesn't have access to
>
> Instead just return undefined
>
> A side effect of this is that it's no longer possible to compile
> functions in a detached context.
>
> BUG=chromium:541703
> R=verwaest@chromium.org,bmeurer@chromium.org
BUG=chromium:541703
R=verwaest@chromium.org
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng
Review-Url: https://codereview.chromium.org/2155503004
Cr-Commit-Position: refs/heads/master@{#37842}
The bug occurs because we do not canonicalize character class ranges
before adding case equivalents. While adding case equivalents, we abort
early for one-byte subject strings, assuming that the ranges are sorted.
Which they are not.
R=marja@chromium.org
BUG=v8:5199
Review-Url: https://codereview.chromium.org/2159683002
Cr-Commit-Position: refs/heads/master@{#37833}
This makes sure that we preserve call's tailness even if we have
introduced a loop exit between the call and the return.
BUG=chromium:628773
Review-Url: https://codereview.chromium.org/2155123002
Cr-Commit-Position: refs/heads/master@{#37832}
In int32 multiplication, if we have a positive integer as input, then we know we can't produce a -0 answer. The same is true if truncation is applied (x * y | 0). Without this information, we have to rather annoyingly check if the result of multiplication is 0, then OR the inputs to check for negativity, and possibly return -0. In TurboFan, we'll deopt in this case.
BUG=
Review-Url: https://codereview.chromium.org/2154073002
Cr-Commit-Position: refs/heads/master@{#37831}
So far TurboFan wasn't adding the deoptimization reasons for eager/soft
deoptimization exits that can be used by either the DevTools profiler or
the --trace-deopt flag. This adds basic support for deopt reasons on
Deoptimize, DeoptimizeIf and DeoptimizeUnless nodes and threads through
the reasons to the code generation.
Also moves the DeoptReason to it's own file (to resolve include cycles)
and drops unused reasons.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2161543002
Cr-Commit-Position: refs/heads/master@{#37823}
Reason for revert:
Break MIPS port.
Original issue's description:
> [interpeter] Move to table based peephole optimizer.
>
> Introduces a lookup table for peephole optimizations.
>
> Fixes some tests using BytecodePeepholeOptimizer::Write() that should
> have been update to use BytecodePeepholeOptimizer::WriteJump().
>
> BUG=v8:4280
> LOG=N
>
> Committed: https://crrev.com/f4234422b93b21a286b0f31799009bcbe8b90b9e
> Cr-Commit-Position: refs/heads/master@{#37819}
TBR=rmcilroy@chromium.org,machenbach@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2161563002
Cr-Commit-Position: refs/heads/master@{#37821}
Introduces a lookup table for peephole optimizations.
Fixes some tests using BytecodePeepholeOptimizer::Write() that should
have been update to use BytecodePeepholeOptimizer::WriteJump().
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/2118183002
Cr-Commit-Position: refs/heads/master@{#37819}
This fixes the deoptimization information for the lazy bailout point
after a [[ToObject]] operation inserted for with statements. The result
value was pushed on the operand stack but erroneously ignored and left
on the operand stack by the FullCodeGenerator.
R=jarin@chromium.org
TEST=mjsunit/regress/regress-5205
BUG=v8:5205
Review-Url: https://codereview.chromium.org/2158443002
Cr-Commit-Position: refs/heads/master@{#37818}
Highlights:
- Record all imports and exports in the ModuleDescriptor.
- Remove ImportDeclaration; instead, introduce a new variable kind for imports.
- Set name on default exported anonymous functions.
Still to do: declaration of namespace imports.
BUG=v8:1569
Review-Url: https://codereview.chromium.org/2108193003
Cr-Commit-Position: refs/heads/master@{#37815}
The GetStackPointer() routine in test-platform uses an inline
assembly code to store the current stack pointer value into a static
variable sp_addr. The existing asm code for S390 uses an ST/STG
instruction, with the memory operand associated with the general ('=g')
constraint to sp_addr.
On GCC 4.8.5, the GCC compiler got confused and treated sp_addr as
an integer operand instead of memory operand, resulting in a store
being emitted that writes to an invalid meory location.
Given the specific store instructions being inlined here, we should
restict the sp_addr operand to explicitly be a memory operand using '=m'
instead of '=g'.
R=bmeurer@chromium.org,jkummerow@chormium.org,rmcilroy@chromium.org,yangguo@chromium.org
BUG=
Review-Url: https://codereview.chromium.org/2158523002
Cr-Commit-Position: refs/heads/master@{#37809}
Delaying for merges caused branch cloning using dummy effect phi inputs,
potentially splitting the effect chain at start.
We still have to delay the creation for loops because we need to break
cycles.
BUG=chromium:628403
Review-Url: https://codereview.chromium.org/2159603002
Cr-Commit-Position: refs/heads/master@{#37808}
This change makes the architecture that we target generated
v8 code for a property of the current toolchain, rather than a
global setting that applies to every toolchain.
This will allow us to properly build two snapshots for two different
architectures in a single build, which is needed for android
webview/monochrome builds.
R=brettw@chromium.org, jochen@chromium.org, michaelbai@chromium.org
BUG=625383
Review-Url: https://codereview.chromium.org/2116913002
Cr-Commit-Position: refs/heads/master@{#37805}
Reason for revert:
Unfortunately, the performance issues are still there on Android.
Original issue's description:
> [ic] [stubs] Don't use Code::flags in megamorphic stub cache hash computations.
>
> This should avoid weird performance issues when changing layout of Code::flags field.
>
> BUG=chromium:618701
>
> Committed: https://crrev.com/aa4140b1ccc114b82700471513c715f68b7c5dac
> Cr-Commit-Position: refs/heads/master@{#37755}
TBR=jkummerow@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:618701
Review-Url: https://codereview.chromium.org/2147213004
Cr-Commit-Position: refs/heads/master@{#37801}
This commit introduces support for writing unwinding tables in the
.eh_frame format, to be inserted in the jitdump read by Linux perf and
emitted with FLAG_perf_prof and FLAG_perf_prof_unwinding_info enabled.
x64 is fully implemented and tested, arm and arm64 are untested and the
unwinding information needs to be expanded, but the mechanism is ready.
BUG=v8:4899
LOG=N
Review-Url: https://codereview.chromium.org/2026313002
Cr-Commit-Position: refs/heads/master@{#37799}
This reverts commit 457c02573c because it caused a
regression in SunSpider/string-fasta and possibly AreWeFastYet/Life. Need to
implement this in a smarter way.
TBR=littledan@chromium.org
BUG=chromium:627729,v8:5113
Review-Url: https://codereview.chromium.org/2149303003
Cr-Commit-Position: refs/heads/master@{#37793}
This makes sure that the uses of PlainPrimitiveToNumber get a more
precise type (so that the uses know how to interpret the output
representation).
BUG=chromium:628516
Review-Url: https://codereview.chromium.org/2151223002
Cr-Commit-Position: refs/heads/master@{#37792}
- Add Simd128 type to Wasm AST types
- Add a pass that converts SIMD machine ops to runtime calls
- Sample opcodes Int32x4Splat, Int32x4ExtractLane and test
- Separate out generic SIMD Machine ops as these cannot be
handled by runtime functions just yet.
LOG=N
BUG=v8:4124
R=bradnelson@chromium.org, bbudge@chromium.org, titzer@chromium.org
Review-Url: https://codereview.chromium.org/1991143002
Cr-Commit-Position: refs/heads/master@{#37789}
Annex B.3.3 of the spec requires that sloppy-mode block-scoped functions
declared by "eval" are hoisted unless doing so would cause an early
error (which is to say, conflict with a lexical declaration). This patch
amends the check for conflicting declarations to include those outside
of the eval itself.
BUG=v8:4468, v8:4479
Review-Url: https://codereview.chromium.org/2112163002
Cr-Commit-Position: refs/heads/master@{#37783}
Instead of unconditionally parsing the catch parameter as an expression
and then recovering if it turns out to be a simple variable proxy
(the overwhelmingly common case), this patch peeks one token ahead
before attempting to parse. This avoids doing the usual RemoveUnresolved
gymnastics in ParseTryStatement, and as a side-effect slightly improves
function name inference for an async arrow function test case.
Review-Url: https://codereview.chromium.org/2151433005
Cr-Commit-Position: refs/heads/master@{#37780}
1) Validation fails for literal indexes too large for accessing a given
heap type
2) Removes the special handling of FloatishDoubleQ, and FloatQDoubleQ;
the inheritance issue that required this special handling was fixed in
another CL.
3) Fix a macro name (from asm_* to ASM_*)
BUG= https://bugs.chromium.org/p/v8/issues/detail?id=4203
TEST=cctest/asmjs/test-asm-typer.cc
LOG=N
Review-Url: https://codereview.chromium.org/2150583003
Cr-Commit-Position: refs/heads/master@{#37776}
Implemented the WebAssembly.Module and WebAssembly.Instance
in terms of the WasmModule::CompileFunctions and
WasmModule::Instantiate APIs.
Added negative tests - for invalid module object.
BUG=
Review-Url: https://codereview.chromium.org/2121593002
Cr-Commit-Position: refs/heads/master@{#37775}
Typed lowering now produces SpeculativeNumberShiftLeft for JSShiftLeft if the type feedback is kSignedSmall or kSigned32.
BUG=v8:4583
LOG=n
Review-Url: https://codereview.chromium.org/2150553002
Cr-Commit-Position: refs/heads/master@{#37762}
Reason for revert:
blink is unhappy about the microtask change
Original issue's description:
> Reland "Don't compile functions in a context the caller doesn't have access to"
>
> Original issue's description:
> > Don't compile functions in a context the caller doesn't have access to
> >
> > Instead just return undefined
> >
> > A side effect of this is that it's no longer possible to compile
> > functions in a detached context.
> >
> > BUG=chromium:541703
> > R=verwaest@chromium.org,bmeurer@chromium.org
>
> BUG=chromium:541703
> R=verwaest@chromium.org
>
> Committed: https://crrev.com/6bceabac5b705b2ce1f52d34650cea1ae3b8c617
> Cr-Commit-Position: refs/heads/master@{#37756}
TBR=verwaest@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:541703
Review-Url: https://codereview.chromium.org/2151843002
Cr-Commit-Position: refs/heads/master@{#37760}
Using the Hydrogen code stub bailout mechanism is not correct for the
string length overflow check in the StringAddStub. Instead make sure we
just throw the proper exception.
R=mstarzinger@chromium.org
BUG=chromium:627934
Review-Url: https://codereview.chromium.org/2146353002
Cr-Commit-Position: refs/heads/master@{#37758}
This adds a missing conversion of time zone names to string primitives
before case conversion and regular expression matching are applied.
This is in sync with ECMA-402, section 12.1.1.1, step 16(a).
R=jochen@chromium.org
TEST=mjsunit/regress/regress-crbug-627935
BUG=chromium:627935
Review-Url: https://codereview.chromium.org/2143003005
Cr-Commit-Position: refs/heads/master@{#37757}
Original issue's description:
> Don't compile functions in a context the caller doesn't have access to
>
> Instead just return undefined
>
> A side effect of this is that it's no longer possible to compile
> functions in a detached context.
>
> BUG=chromium:541703
> R=verwaest@chromium.org,bmeurer@chromium.org
BUG=chromium:541703
R=verwaest@chromium.org
Review-Url: https://codereview.chromium.org/2143893005
Cr-Commit-Position: refs/heads/master@{#37756}
This should avoid weird performance issues when changing layout of Code::flags field.
BUG=chromium:618701
Review-Url: https://codereview.chromium.org/2147433002
Cr-Commit-Position: refs/heads/master@{#37755}
Original commit message:
Also, CodeGenerator::MakeCodeEpilogue now accepts an optional pointer
to a EhFrameWriter and will attach unwinding information to the code
object when passed one.
Reason for reverting:
The STATIC_CONST_MEMBER_DEFINITION in eh-frame-writer-unittest.cc
causes a compiler error on V8 Win64 - clang buildbot.
Removing that bit.
BUG=v8:4899
LOG=N
Review-Url: https://codereview.chromium.org/2023503002
Cr-Commit-Position: refs/heads/master@{#37754}
If --turbo-type-feedback is off, the type hints on the operators will
just be kAny, so we don't need to do additional checks in the
JSTypedLowering reducer.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2144203002
Cr-Commit-Position: refs/heads/master@{#37750}
Reason for revert:
Breaks the roll, possibly win gn:
https://codereview.chromium.org/2148863002/
Original issue's description:
> [interpreter] Reduce dependencies in bytecodes.{h,cc}
>
> This CL reduces the number of dependencies bytecodes.{h,cc} to facilitate
> generating the bytecode peephole optimizer table during build. Specifically,
> it avoids depending on v8_base.
>
> BUG=v8:4280
> LOG=N
>
> Committed: https://crrev.com/4edebb1cd870ae6c1359ad54f83e618e185883b1
> Cr-Commit-Position: refs/heads/master@{#37715}
TBR=mstarzinger@chromium.org,rmcilroy@chromium.org,oth@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4280
Review-Url: https://codereview.chromium.org/2151693003
Cr-Commit-Position: refs/heads/master@{#37743}
Reason for revert:
Causes crashes on Canary
Original issue's description:
> Don't compile functions in a context the caller doesn't have access to
>
> Instead just return undefined
>
> A side effect of this is that it's no longer possible to compile
> functions in a detached context.
>
> BUG=chromium:541703
> R=verwaest@chromium.org,bmeurer@chromium.org
> CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng
>
> Committed: https://crrev.com/992e34c21635b179a993b82ac1d81753e7a6a57a
> Cr-Commit-Position: refs/heads/master@{#37657}
TBR=bmeurer@chromium.org,verwaest@chromium.org,jochen@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=chromium:541703, chromium:628053
Review-Url: https://codereview.chromium.org/2148163002
Cr-Commit-Position: refs/heads/master@{#37736}
The runtime JIT function is passed in the function table to hook up the compiled code and the starting address of the memory to locate the bytes to be compiled.
BUG=5044
Review-Url: https://codereview.chromium.org/2137993003
Cr-Commit-Position: refs/heads/master@{#37735}
Reason for revert:
Correcting issue.
Original issue's description:
> Revert of Add errors for declarations which conflict with catch parameters. (patchset #6 id:100001 of https://codereview.chromium.org/2109733003/ )
>
> Reason for revert:
> Fuzzer claims `try { \"\" ; } catch(x) { let x1 = [1,,], x = x; }` causes a crash.
>
> Original issue's description:
> > Add errors for declarations which conflict with catch parameters.
> >
> > Catch parameters are largely treated as lexical declarations in the
> > block which contains their body for the purposes of early syntax errors,
> > with some exceptions outlined in B.3.5. This patch introduces most of
> > those errors, except those from `eval('for (var e of ...);')` inside of
> > a catch with a simple parameter named 'e'.
> >
> > Note that annex B.3.5 allows var declarations to conflict with simple
> > catch parameters, except when the variable declaration is the init of a
> > for-of statement.
> >
> > BUG=v8:5112,v8:4231
> >
> > Committed: https://crrev.com/2907c726b2bb5cf20b2bec639ca9e6a521585406
> > Cr-Commit-Position: refs/heads/master@{#37462}
>
> TBR=littledan@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=v8:5112,v8:4231
>
> Committed: https://crrev.com/8834d5ecb559001c87c42322969471da60574a8c
> Cr-Commit-Position: refs/heads/master@{#37464}
R=littledan@chromium.org
BUG=v8:5112,v8:4231
Review-Url: https://codereview.chromium.org/2119933002
Cr-Commit-Position: refs/heads/master@{#37728}
* Rename Atomics.futexWait -> Atomics.wait
* Rename Atomics.futexWake -> Atomics.wake
* Remove Atomics.futexWakeOrRequeue
* Return value of Atomics.wait is now a string: "ok", "not-equal" or
"timed-out"
* Update comments that reference URL for ecmascript_sharedmem to
https://github.com/tc39/ecmascript_sharedmem
Review-Url: https://codereview.chromium.org/2143443002
Cr-Commit-Position: refs/heads/master@{#37727}
This fixes the deoptimization information for the lazy bailout point
after a [[ToName]] operation inserted for object literals and class
literals. The result value was erroneously ignored.
R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-627828
BUG=chromium:627828
Review-Url: https://codereview.chromium.org/2149493003
Cr-Commit-Position: refs/heads/master@{#37719}
This CL reduces the number of dependencies bytecodes.{h,cc} to facilitate
generating the bytecode peephole optimizer table during build. Specifically,
it avoids depending on v8_base.
BUG=v8:4280
LOG=N
Review-Url: https://codereview.chromium.org/2135273002
Cr-Commit-Position: refs/heads/master@{#37715}
- Adds move/swap handling for 4 and 16 bytes to ia32.
- Register allocator now only requests 4 bytes for floats on ia32 and arm.
- We probably need similar support in mips.
LOG=N
BUG=v8:4124
Review-Url: https://codereview.chromium.org/2027043002
Cr-Commit-Position: refs/heads/master@{#37714}
After this CL we can avoid using Code::flags in hash computations for megamorphic
stub caches and therefore the unused ICState field can be finally removed from flags.
BUG=chromium:618701
Review-Url: https://codereview.chromium.org/2123983004
Cr-Commit-Position: refs/heads/master@{#37708}
Original commit message:
Also, CodeGenerator::MakeCodeEpilogue now accepts an optional pointer
to a EhFrameWriter and will attach unwinding information to the code
object when passed one.
Reason for reverting:
The STATIC_CONST_MEMBER_DEFINITION in eh-frame-writer-unittest.cc
causes a compiler error on V8 Win64 - clang buildbot.
Removing that bit.
BUG=v8:4899
LOG=N
Review-Url: https://codereview.chromium.org/2023503002
Cr-Commit-Position: refs/heads/master@{#37707}
If operands are loaded as unsigned 32-bit integer, they need to be sign extended to 64 bits.
TEST=cctest/test-run-machops/RunWord32AndAndWord32ShrP, cctest/test-run-machops/RunWord32OrP,
cctest/test-run-machops/RunWord32ShrP, cctest/test-run-machops/RunWord32XorP
BUG=
Review-Url: https://codereview.chromium.org/2147883002
Cr-Commit-Position: refs/heads/master@{#37705}
This fully deprecates all uses of the RUNTIME_ASSERT macro and removes
the macro and underlying logging function in question. All uses have
been replaces with CHECK macros which crash safely even in production.
It makes sure we discover abuse of runtime functions in the wild early
and also abort the process safely. Breaking assumptions in any runtime
function can no longer accidentally be caught by JavaScript.
R=yangguo@chromium.org
BUG=v8:5066
Review-Url: https://codereview.chromium.org/2132493002
Cr-Commit-Position: refs/heads/master@{#37704}
This makes sure the {AstGraphBuilder} respects the catch-prediction that
is provided by the parser along with each {TryStatement}. This is needed
for try-blocks materialized by the parser not to influence predictions
users expect when using the debugger.
R=neis@chromium.org
TEST=mjsunit/debug-exceptions
BUG=v8:5183
Review-Url: https://codereview.chromium.org/2147573002
Cr-Commit-Position: refs/heads/master@{#37702}
Previously, the following schedule fragment:
1: Parameter[0](0)
2: Parameter[1](0)
7: Int32Constant[1]
8: Int32Sub(2, 7)
9: Load[kRepTagged|kTypeAny](1, 8)
would generate the following code (on ia32):
mov eax,[ebp+0x8]
mov ecx,[ebp+0xc]
sub eax,0x1
mov eax,[eax+ecx*1]
Now it generates:
mov eax,[ebp+0x8]
mov ecx,[ebp+0xc]
mov eax,[eax+ecx*1-1]
Similar pattern matching also now works on x64.
BUG=v8:5192
LOG=N
Review-Url: https://codereview.chromium.org/2137323003
Cr-Commit-Position: refs/heads/master@{#37701}
Collect type feedback in the call bytecode handler. The current
implementation only collects feedback for JS function objects. The other
objects and Array functions do not collect any feedback. They will be
marked Megamorphic.
BUG=v8:4280, v8:4780
LOG=N
Review-Url: https://codereview.chromium.org/2122183002
Cr-Commit-Position: refs/heads/master@{#37700}
For JSToBoolean with Number inputs we still called out to the
ToBooleanStub, even though we easily handle them inline nowadays.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2145923002
Cr-Commit-Position: refs/heads/master@{#37699}
To correctly support instantiating a compiled module multiple times, we clone the
compiled module each time we create an instance, since some of the data is specific
to the instance - e.g. export code, wasm functions, indirect table.
BUG=v8:5072
Review-Url: https://codereview.chromium.org/2134593002
Cr-Commit-Position: refs/heads/master@{#37692}
Reason for revert:
The STATIC_CONST_MEMBER_DEFINITION in eh-frame-writer-unittest.cc causes a compiler error on V8 Win64 - clang buildbot. Removing that bit should be sufficient.
Original issue's description:
> Implement .eh_frame writer and disassembler.
>
> Also, CodeGenerator::MakeCodeEpilogue now accepts an optional pointer
> to a EhFrameWriter and will attach unwinding information to the code
> object when passed one.
>
> BUG=v8:4899
> LOG=N
>
> Committed: https://crrev.com/27d810e63b744b5b3d9aa28ff21413247773e6c2
> Cr-Commit-Position: refs/heads/master@{#37683}
TBR=rmcilroy@chromium.org,jarin@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4899
Review-Url: https://codereview.chromium.org/2143033002
Cr-Commit-Position: refs/heads/master@{#37688}
When trying to clone a branch, the ControlFlowOptimizer gave up as soon as it found a Phi/EffectPhi node that could not be placed directly below the IfTrue or IfFalse control paths.
Moving the step in the EffectControlLinearizer phase, after the first schedule, works around the problem by looking at the successor blocks.
BUG=
Review-Url: https://codereview.chromium.org/2139593002
Cr-Commit-Position: refs/heads/master@{#37687}
This solves an issue with throws inside for-of always being marked as caught.
BUG=v8:5183
Review-Url: https://codereview.chromium.org/2146493002
Cr-Commit-Position: refs/heads/master@{#37686}
Also, CodeGenerator::MakeCodeEpilogue now accepts an optional pointer
to a EhFrameWriter and will attach unwinding information to the code
object when passed one.
BUG=v8:4899
LOG=N
Review-Url: https://codereview.chromium.org/2023503002
Cr-Commit-Position: refs/heads/master@{#37683}
- check that packed elements do not contain the_hole (with fix)
- verify argument objects with elements kind
- use JSObjectVerifiy in all JSObject "subclasses"
- change initialization order for ArrayLiteralBoilerplate to simplify verification
BUG=v8:5188
Review-Url: https://codereview.chromium.org/2126613002
Cr-Commit-Position: refs/heads/master@{#37680}
This is another point where we add inconsistent behavior between simple and
detailed stack traces. The functionality also does not seem to be used in
chrome anymore when uncaught exceptions are thrown. Remove it to reduce
maintenance burden.
BUG=624285
R=yangguo@chromium.org
Review-Url: https://codereview.chromium.org/2141523002
Cr-Commit-Position: refs/heads/master@{#37673}
I removed or replaced some values in the list of float and double values
in value-helper.h which cannot be represented precisely as floats or
doubles, respectively.
R=titzer@chromium.org
Review-Url: https://codereview.chromium.org/2135243004
Cr-Commit-Position: refs/heads/master@{#37671}
This removes the checking for use-def and def-use chain links from the
graph verification. Presence of such links can only be violated by a bug
in the actual {Node} implementation itself. That container class is also
covered by unit tests.
The verification in question was useful in the early days when the graph
implementation itself was prone to bugs. By now it has stabilized and
spending O(n^2) time during graph verification is too wasteful to still
be considered a reasonable trade-off.
R=jarin@chromium.org
TEST=unittests/NodeTest.*
Review-Url: https://codereview.chromium.org/2140973003
Cr-Commit-Position: refs/heads/master@{#37670}
The PlainPrimitiveToNumber operator performs a superset of the operations
previously performed by the BooleanToNumber and StringToNumber operators,
so we can just use the special lowering rules for PlainPrimitiveToNumber
based on the input type and get rid of the specialized operators.
R=jarin@chromium.org
Review-Url: https://codereview.chromium.org/2139183002
Cr-Commit-Position: refs/heads/master@{#37669}
This CL separates the check whether something is tail-callable from
the computation of the size of the stack parameters that a function
takes.
In order to track this precisely, the stack parameter size calculation
uses the recently landed MachineType information that's embedded
in return and parameter value LinkageLocations.
Review-Url: https://codereview.chromium.org/2121753002
Cr-Commit-Position: refs/heads/master@{#37668}
Remove obsolete definitions from macros.py, and drop the now obsolete
%_ToPrimitive, %_ToPrimitive_Number, %_ToPrimitive_String, %_ToName
and the %ToPrimitive_String intrinsics/runtime entries.
R=yangguo@chromium.org
BUG=v8:5049
Review-Url: https://codereview.chromium.org/2137203002
Cr-Commit-Position: refs/heads/master@{#37665}
Instead just return undefined
A side effect of this is that it's no longer possible to compile
functions in a detached context.
BUG=chromium:541703
R=verwaest@chromium.org,bmeurer@chromium.org
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng
Review-Url: https://codereview.chromium.org/2034083002
Cr-Commit-Position: refs/heads/master@{#37657}
When the scanner finds a '-->', it's either part of an HTMLCloseComment
or a '--' followed by a '>'. Previously, only a preceding newline would
make it an HTMLCloseComment. Now, a preceding multiline comment also
makes it an HTMLCloseComment. The effect is that now the following is
not a SyntaxError:
x/*
*/-->this is now a comment
BUG=v8:5142
LOG=y
Review-Url: https://codereview.chromium.org/2119763003
Cr-Commit-Position: refs/heads/master@{#37656}
This patch just checks for a stack overflow and returns failure
from the cases which Clusterfuzz found. However, there may be
more locations in the parser which need similar treatment.
R=caitpotter88@gmail.com,neis
BUG=v8:4483,chromium:624300
Review-Url: https://codereview.chromium.org/2135503002
Cr-Commit-Position: refs/heads/master@{#37655}
This removes the frame state input representing the before-state from
nodes having any comparison operator. Lowering that inserts number
conversions of the inputs has to be disabled when deoptimization is
enabled, because the frame state layout is no longer known.
R=jarin@chromium.org
BUG=v8:5021
Review-Url: https://codereview.chromium.org/2134173002
Cr-Commit-Position: refs/heads/master@{#37646}
This extends pretenuring decisions based on allocation sites to heap
numbers that are allocated as part of object literals. It ensures memory
locality of a bigger enclosure of the deep copy of an object literal.
R=bmeurer@chromium.org
TEST=cctest/test-heap/OptimizedPretenuringMixedInObjectProperties
Review-Url: https://codereview.chromium.org/2135933002
Cr-Commit-Position: refs/heads/master@{#37645}
By adding MachineType to LinkageLocation, it is possible not only to reason
about the location of a LinkageLocation on the stack, but also about it's
size. This will be useful in follow-on CLs that attempt to merge some of the
parameter passing logic of tail calls and normal (non-tail) calls.
As a nice side-effect, it is no longer necessary to separately keep a
MachineSignature in a CallDescriptor, because the MachineTypes contianed in
LinkageLocation for all of the Descriptor's parameters and return types are
sufficient. This CL therefore removes the MachineSignature from the
CallDescriptor and adjusts all the calling code accordingly, simplifying and
de-duplicating code in a bunch of places.
R=titzer@chromium.org, bmeurer@chromium.org
LOG=N
Review-Url: https://codereview.chromium.org/2124023003
Cr-Commit-Position: refs/heads/master@{#37633}
CallSite::IsConstructor() was unable to recognize builtin construct stubs
(NumberConstructor_ConstructStub and StringConstructor_ConstructStub) as
constructors, and thus these frames were not formatted correctly in stack
traces.
Fix this by explicitly marking their Code objects as construct stubs and
passing along a special receiver value when we encounter such cases in
CaptureSimpleStackTrace.
R=mstarzinger@chromium.org, yangguo@chromium.org
BUG=
Review-Url: https://codereview.chromium.org/2125163004
Cr-Commit-Position: refs/heads/master@{#37631}
This enables tests which verify allocation site feedback is used and
influences pretenuring decisions. By now TurboFan is respecting such
feedback. Ignition however doesn't provide such feedback yet.
R=mvstanton@chromium.org
Review-Url: https://codereview.chromium.org/2135563003
Cr-Commit-Position: refs/heads/master@{#37628}
