To make async/await catch prediction work well, this patch regularizes
the exception events sent to DevTools from various places in the Promise
lifecycle. The core is that there should be an exception event when the
rejection first starts, rather than when it is propagated.

- Several cases within Promise code which propagate errors are
  modified to not trigger a new ExceptionEvent in that case, such
  as .then on a rejected Promise and returning a rejected Promise
  from .then, as well as Promise.race and Promise.all.
- Make Promise.reject() create an ExceptionEvent, subject to catch
  prediction based on the Promise stack. This is important
  so that, e.g., if "await Promise.reject()" will trigger a new
  throw (rather than a silent rethrow of something that never
  triggered an event in the first place).

BUG=v8:5167

Review-Url: https://codereview.chromium.org/2244003003
Cr-Commit-Position: refs/heads/master@{#38847}

R=littledan@chromium.org
BUG=v8:4483

Review-Url: https://codereview.chromium.org/2270223002
Cr-Commit-Position: refs/heads/master@{#38846}

Introduces support for using

try {
} finally {
}

in wasm.

BUG=

Review-Url: https://codereview.chromium.org/2240743003
Cr-Commit-Position: refs/heads/master@{#38845}

This gets rid of the BindingsKind flag. It replaces the factory argument with a bool that indicates whether free variables should be resolved as well.

BUG=

Review-Url: https://codereview.chromium.org/2262393004
Cr-Commit-Position: refs/heads/master@{#38844}

 - Instruction selection, code generation, test for Splat/Extract
 - Fixes for AstS128 Locals in wasm

R=bbudge@chromium.org, titzer@chromium.org

Review-Url: https://codereview.chromium.org/2264533002
Cr-Commit-Position: refs/heads/master@{#38843}

"ExpressionProductions" was missing the plural. I don't think this
changed any behavior, but I'd rather be safe than sorry. Also
removed redundant mention of TailCall production.

A future patch will attempt to make calls to Accumulate make more sense,
in general.

R=littledan@chromium.org

Review-Url: https://codereview.chromium.org/2270153002
Cr-Commit-Position: refs/heads/master@{#38842}

In particular, this covers one caller of CheckDestructuringElement
that didn't have tests before.

R=caitp@igalia.com

Review-Url: https://codereview.chromium.org/2267153002
Cr-Commit-Position: refs/heads/master@{#38841}

Port b305c7df

Original commit message:

    Drive-by fix: the order of parameters in the BinaryOpWithFeedback TurboFan code stubs now reflects the convention of having the context at the end.

R=epertoso@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com

BUG=v8:5273
LOG=N

Review-Url: https://codereview.chromium.org/2264353003
Cr-Commit-Position: refs/heads/master@{#38840}

The only two places where these Forgive methods were called
was in ParseAssignmentExpression just at the time we were
calling Accumulate(). So instead of Forgiving, we can simply
not accumulate the bits that would have been forgiven.

Also slightly restructures the nearby code in
ParseAssignmentExpression, and removes the use of non-const
references in ExpressionClassifier.

Review-Url: https://codereview.chromium.org/2267223002
Cr-Commit-Position: refs/heads/master@{#38839}

Adds a check so that module validation fails if there are any
assignments to immutable identifiers (e.g., module name, module
parameters, stdlib imports.)

BUG= https://bugs.chromium.org/p/chromium/issues/detail?id=640194

Review-Url: https://codereview.chromium.org/2268363002
Cr-Commit-Position: refs/heads/master@{#38838}

This patch removes 26 elements of the (pre)parser traits objects.
Some methods are removed completely and called directly from the
implementation objects:

- ParseAsyncFunctionExpression
- ParseClassLiteral
- ParseDoExpression
- ParseEagerFunctionBody
- ParseFunctionLiteral
- ParseV8Intrinsic

Some methods have to be moved to at least one implementation object:

- AddTemplateExpression
- AddTemplateSpan
- CheckConflictingVarDeclarations
- CloseTemplateLiteral
- MarkCollectedTailCallExpressions
- MarkTailPosition
- OpenTemplateLiteral
- ParseAsyncArrowSingleExpressionBody
- PrepareSpreadArguments
- QueueDestructuringAssignmentForRewriting
- QueueNonPatternForRewriting
- RewriteAssignExponentiation
- RewriteAwaitExpression
- RewriteDestructuringAssignments
- RewriteExponentiation
- RewriteNonPattern
- RewriteYieldStar
- SkipLazyFunctionBody
- SpreadCall
- SpreadCallNew

Also, the inner class/struct TemplateLiteralState is moved to the
implementation objects.

R=adamk@chromium.org, marja@chromium.org
BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2267783002
Cr-Commit-Position: refs/heads/master@{#38837}

We anyway have its index in params_, so just always access through params_.

BUG=v8:5209

Review-Url: https://codereview.chromium.org/2275573002
Cr-Commit-Position: refs/heads/master@{#38836}

BUG=chromium:148757

Review-Url: https://codereview.chromium.org/2262013002
Cr-Commit-Position: refs/heads/master@{#38835}

Before this patch all tracing scopes in incremental marking would be reset
during a gc tracer start/stop cycle. This patch handles scopes the same way it
does other incremental marking metrics.

Also:
- Align finalization metric with regular marking metric.
- Smaller cleanups

BUG=chromium:639818

Review-Url: https://codereview.chromium.org/2273673002
Cr-Commit-Position: refs/heads/master@{#38834}

R=bjaideep@ca.ibm.com
BUG=

Review-Url: https://codereview.chromium.org/2270523002
Cr-Commit-Position: refs/heads/master@{#38833}

Drive-by fix: the order of parameters in the BinaryOpWithFeedback TurboFan code stubs now reflects the convention of having the context at the end.

BUG=v8:5273

Review-Url: https://codereview.chromium.org/2263253002
Cr-Commit-Position: refs/heads/master@{#38832}

BUG=v8:5260

Review-Url: https://codereview.chromium.org/2263363002
Cr-Commit-Position: refs/heads/master@{#38831}

BUG=chromium:148757

Review-Url: https://codereview.chromium.org/2265603002
Cr-Commit-Position: refs/heads/master@{#38830}

On FreeBSD, sem_t is a struct with a couple of uint32_t fields. It only
needs dword alignment on 64 bits architectures, not the qword (pointer)
alignment that the CHECK currently enforces.

BUG=

Review-Url: https://codereview.chromium.org/2268993002
Cr-Commit-Position: refs/heads/master@{#38829}

This flag was only set on receiver scopes (declaration scopes) already. This makes it statically obvious.

BUG=v8:5209

Review-Url: https://codereview.chromium.org/2268333002
Cr-Commit-Position: refs/heads/master@{#38828}

Revert of [heap] Tracer: Handle incremental marking scopes (patchset #4 id:100001 of https://codereview.chromium.org/2264033002/ )

Reason for revert:
Unittest fails on win32 debug:
https://build.chromium.org/p/client.v8/builders/V8%20Win32%20-%20debug/builds/4188/steps/Check/logs/GCTracerTest.Incremen..

Original issue's description:
> [heap] Tracer: Handle incremental marking scopes
>
> Before this patch all tracing scopes in incremental marking would be reset
> during a gc tracer start/stop cycle. This patch handles scopes the same way it
> does other incremental marking metrics.
>
> Also:
> - Align finalization metric with regular marking metric.
> - Smaller cleanups
>
> BUG=chromium:639818
> R=jochen@chromium.org
>
> Committed: https://crrev.com/300a8f97472b88ff2f94eb977c36b4bf1bedabf1
> Cr-Commit-Position: refs/heads/master@{#38822}

TBR=jochen@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:639818

Review-Url: https://codereview.chromium.org/2275583002
Cr-Commit-Position: refs/heads/master@{#38827}

BUG=v8:5260

Review-Url: https://codereview.chromium.org/2262313002
Cr-Commit-Position: refs/heads/master@{#38826}

Non-CrOS builds should use clang for snapshot_toolchain, even on builds which use gcc for the target device. Change the default value for snapshot_toolchain to always use clang, except on ChromeOS gcc builds. In practice, every platform except ChromeOS always uses clang, so this should not affect any platform except non-CrOS gcc builds (like Cast)

BUG= internal b/30873074

Review-Url: https://codereview.chromium.org/2265983002
Cr-Commit-Position: refs/heads/master@{#38825}

- The static method CopyChars was actually used and has been extracted.
- It was used in tests, where it's been replaced w/ ExternalOneByteString...
- Only one test actually relied on Utf8 handling (as opposed to ASCII only),
  and that was the test testing Utf8ToUtf16CharacterStream itself.

+66 -277 LOC :)

BUG=v8:4947

Review-Url: https://codereview.chromium.org/2256273002
Cr-Commit-Position: refs/heads/master@{#38824}

BUG=v8:5260

Review-Url: https://codereview.chromium.org/2268673002
Cr-Commit-Position: refs/heads/master@{#38823}

Before this patch all tracing scopes in incremental marking would be reset
during a gc tracer start/stop cycle. This patch handles scopes the same way it
does other incremental marking metrics.

Also:
- Align finalization metric with regular marking metric.
- Smaller cleanups

BUG=chromium:639818
R=jochen@chromium.org

Review-Url: https://codereview.chromium.org/2264033002
Cr-Commit-Position: refs/heads/master@{#38822}

BUG=

Review-Url: https://codereview.chromium.org/2269033002
Cr-Commit-Position: refs/heads/master@{#38821}

This makes sure the check of the return value of an inlined constructor
call is properly wired into the control chain. The check only happens on
successful completion of the underlying call and hence is wired into the
success latch of the control projections.

R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2272633002
Cr-Commit-Position: refs/heads/master@{#38820}

This patch applies an adaptation of the Curiously Recurring Template
Pattern to the parser objects.  The result is roughly:

    // Common denominator, needed to avoid cyclic dependency.
    // Instances of this template will end up with very minimal
    // definitions, ideally containing just typedefs.
    template <typename Impl>
    class ParserBaseTraits;

    // The parser base object, which should just implement pure
    // parser behavior.  The Impl parameter is the actual derived
    // class (according to CRTP), which implements impure parser
    // behavior.
    template <typename Impl>
    class ParserBase : public ParserBaseTraits<Impl> { ... };

    // And then, for each parser variant:
    class Parser;

    template <>
    class ParserBaseTraits<Parser> { ... };

    class Parser : public ParserBase<Parser> { ... };

Using the CRTP, we will ultimately achieve two goals:
(1) clean up the traits objects, but most importantly
(2) clearly separate pure/impure parser implementation and facilitate
experimentation with different parser variants.

R=adamk@chromium.org, marja@chromium.org
BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2267663002
Cr-Commit-Position: refs/heads/master@{#38819}

Rebuilding (after touching certain files) is crazy slow because
includes are out of control.

Fixing it:
- Don't include stuff in headers unless necessary.
- Include the stuff you need, not some other stuff that happens to include the
 stuff you need.

BUG=v8:5294

Review-Url: https://codereview.chromium.org/2268303002
Cr-Commit-Position: refs/heads/master@{#38818}

When preparing compilation, we can't delay error reporting either.

Also put handles during internalization into a deferred handle scope.

BUG=v8:5215
R=marja@chromium.org,rmcilory@chromium.org

Review-Url: https://codereview.chromium.org/2268983002
Cr-Commit-Position: refs/heads/master@{#38817}

Also, clarify comments about how semaphores work

BUG=none
R=mlippautz@chromium.org

Review-Url: https://codereview.chromium.org/2270703002
Cr-Commit-Position: refs/heads/master@{#38816}

This makes sure the deoptimizer picks bytecode prepared for debugging
when materializing an interpreted frame if one is available. This is
normally done by the interpreter entry trampoline and hence needs to be
replicated by the deoptimizer.

R=jarin@chromium.org

Review-Url: https://codereview.chromium.org/2271443003
Cr-Commit-Position: refs/heads/master@{#38815}

Even though there is no scope chain, just the empty outer scope.

R=marja@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2273553003
Cr-Commit-Position: refs/heads/master@{#38814}

This patch const-qualifies some methods of ParserBase.
It also unqualifies some methods of Parser and Preparser.
The reason for the latter is that, in principle, the methods
of AstNodeFactory should be allowed to change the factory's
state, therefore should not be const and should not be used
from const-qualified parser/pre-parser methods.

R=adamk@chromium.org, marja@chromium.org
BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2263973003
Cr-Commit-Position: refs/heads/master@{#38813}

This avoids checking for outer_scope == nullptr in Scope::Scope

BUG=v8:5209

Review-Url: https://codereview.chromium.org/2266973002
Cr-Commit-Position: refs/heads/master@{#38812}

  Port 28e3467a (r38361)

  original commit message:
    Adding new methods to the code stub assembler and interpreter
    assembler to combine loading and untagging SMIs, so that on 64-bit
    architectures we can avoid loading the full 64 bits and load the
    32 interesting bits directly instead.

BUG=

Review-Url: https://codereview.chromium.org/2265043002
Cr-Commit-Position: refs/heads/master@{#38811}

This avoids needing to allocate a zonelist on the fly later, sorting variables_, for which we also need to keep track of order in the hashmap.

In a later phase we can make sure that Variable is always uniquely in either of params_, temps_ and ordered_variables_. In that case we can use a linked list through Variable.

BUG=v8:5209

Review-Url: https://codereview.chromium.org/2264053003
Cr-Commit-Position: refs/heads/master@{#38810}

This changes the compilation pipeline so that mixed stacks are allowed
when bytecode is preserved. This means there can be activations of both,
"baseline" as well as "unoptimized" code active on the stack at the same
time for any single given function.

R=rmcilroy@chromium.org
BUG=v8:4280

Review-Url: https://codereview.chromium.org/2267693002
Cr-Commit-Position: refs/heads/master@{#38809}

BUG=chromium:570268,chromium:621829

Review-Url: https://codereview.chromium.org/2233683002
Cr-Commit-Position: refs/heads/master@{#38808}