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}
In a few places in the parser base, we were forced to initialize
variables of type ExpressionT even if it's not necessary, as they
are assigned to later on before their use. This was required
because, for the case of the preparser, ExpressionT is
PreParserExpression which had no default constructor.
This patch adds a default constructor, equivalent to EmptyExpression
for this class, and gets rid of the unnecessary initializations.
R=adamk@chromium.org, littledan@chromium.org
BUG=
LOG=N
Review-Url: https://codereview.chromium.org/2162763003
Cr-Commit-Position: refs/heads/master@{#37884}
This will allow us to move more state from Scope into ScopeState and lazily allocate full Scopes only when needed.
BUG=v8:5209
Review-Url: https://codereview.chromium.org/2160593002
Cr-Commit-Position: refs/heads/master@{#37858}
This replaces the vtable on AstNode with a NodeType tag. The visitors replace double dispatch with a single switch over the NodeType.
For now, visitors with subclasses still have virtual methods themselves. We should probably specialize them later as well.
The uint8_t NodeType allows us to better pack memory, saving 8-16 bytes on many AST nodes (with additional packing that I'll do in a follow-up CL)
BUG=
Review-Url: https://codereview.chromium.org/2142233003
Cr-Commit-Position: refs/heads/master@{#37788}
Add a flag harmony_trailing_commas_in_parameters that allows trailing
commas in function parameter declaration lists and function call
parameter lists. Trailing commas are allowed in parenthetical lists like
`(a, b, c,)` only if the next token is `=>`, thereby making it an arrow
function declaration. Only 1 trailing comma is allowed, not `(a,,)`. A
trailing comma must follow a non-rest parameter, so `(,)` and `(...a,)`
are still SyntaxErrors. However, a trailing comma is allowed after a
spread parameter, e.g. `a(...b,);`.
Add parser tests for all of the above.
BUG=v8:5051
LOG=y
Review-Url: https://codereview.chromium.org/2094463002
Cr-Commit-Position: refs/heads/master@{#37355}
Previously, an async arrow function would be parsed if any valid
ConditionalExpression began with the identifier "async", and its following token
was on the same line.
So for example, `async.bar foo => 1` was parsed as a valid async arrow function.
This patch corrects this behaviour by asserting that the following token is a
valid arrow parameters start.
BUG=v8:4483
R=littledan@chromium.org, henrique.ferreiro@gmail.com
Review-Url: https://codereview.chromium.org/2089733002
Cr-Commit-Position: refs/heads/master@{#37154}
This patch attempts to reduce the (stack) memory footprint of
expression classifiers. Instead of keeping space in each
classifier for all possible error messages that will
(potentially) be reported, if an expression turns out to be
a pattern or a non-pattern, such error messages are placed in
a list shared by the FunctionState and each classifier keeps a
couple of indices in this list. This requires that classifiers
are used strictly in a stack-based fashion, which is also in line
with my previous patch for revisiting non-pattern rewriting.
R=adamk@chromium.org
BUG=chromium:528697
Review-Url: https://codereview.chromium.org/1708193003
Cr-Commit-Position: refs/heads/master@{#36897}
We ported hashmap.h into libsampler as a workaround before, so the main focus of
this patch is to reduce code duplication. This patch moves the hashmap into
src/base as well as creates DefaultAllocationPolicy using malloc and free.
BUG=v8:5050
LOG=n
Review-Url: https://codereview.chromium.org/2010243003
Cr-Commit-Position: refs/heads/master@{#36873}
Annex B 3.3 applies only for ordinary FunctionDeclarations, not
GeneratorDeclarations or AsyncFunctionDeclarations. This patch
- Skips applying Annex B 3.3 to async functions
- Adds a flag to refrain from applying it to generators
- UseCounter for how often duplicate function in block occurs
with generators (unclear how to measure need for hoisting from block)
BUG=v8:4806
Review-Url: https://codereview.chromium.org/1995863002
Cr-Commit-Position: refs/heads/master@{#36557}
Some IdentifierNames are only included in the set of FutureReservedWords
for strict mode code. Outside of strict mode, these IdentifierNames may
be used as Identifiers. Notably, this includes their use as
BindingIdentifiers in LexicalBindings.
From ES2015 12.1.1 Static Semantics: Early Errors (Identifiers):
> It is a Syntax Error if this phrase is contained in strict mode code
> and the StringValue of IdentifierName is: "implements", "interface",
> "let", "package", "private", "protected", "public", "static", or
> "yield".
http://www.ecma-international.org/ecma-262/6.0/#sec-identifiers-static-semantics-early-errors
Due to a error in its heuristic for disambiguating the `let` token, V8
does not currently allow any of the strict-mode-only FutureReservedWords
to be used as a BindingIdentifier outside of strict mode.
Update V8's heuristic for disambiguating the `let` keyword to account
for strict mode, enabling these IdentifierNames to be used
BUG=v8:4918
LOG=N
R=adamk@chromium.org
Review-Url: https://codereview.chromium.org/1891453005
Cr-Commit-Position: refs/heads/master@{#36296}
This adds back the instanceof operator support in the backends and
introduces a @@hasInstance protector cell on the isolate that guards the
fast path for the InstanceOfStub. This way we recover the ~10%
regression on Octane EarleyBoyer in Crankshaft and greatly improve
TurboFan and Ignition performance of instanceof.
R=ishell@chromium.orgTBR=hpayer@chromium.org,rossberg@chromium.org
BUG=chromium:597249, v8:4447
LOG=n
Review-Url: https://codereview.chromium.org/1980483003
Cr-Commit-Position: refs/heads/master@{#36275}
Unlike previous implementation where the 'continue' keyword was a feature of a return statement the keyword is now recognized as a part of expression. Error reporting was significantly improved.
--harmony-explicit-tailcalls option is now orthogonal to --harmony-tailcalls so we can test both modes at the same time.
This CL also adds %GetExceptionDetails(exception) that fetches hidden |start_pos| and |end_pos| values from the exception object.
BUG=v8:4915
LOG=N
Review-Url: https://codereview.chromium.org/1928203002
Cr-Commit-Position: refs/heads/master@{#36024}
Compiler backends get their language mode from the current
function, but should instead be deriving it from the current scope.
This allows proper handling of the always-strictness of class declarations
and expressions, and in particular the treatment of 'eval' calls in an
extends clause as a strict eval.
Also fix the parser's RecordEvalCall logic to only reach out to the
DeclarationScope in sloppy mode, which fixes the strange case of a
sloppy function thinking it contains a sloppy eval when in fact
it contains only a strict eval.
BUG=v8:4970
LOG=n
Review-Url: https://codereview.chromium.org/1931003003
Cr-Commit-Position: refs/heads/master@{#36001}
Yield expressions are not allowed in formal parameter initializers of
generators, but we weren't properly catching the case where the yield
expression appeared in the 'extends' clause of a class expression.
They also aren't allowed in arrow functions, which we were failing to
catch due to not looking at the obscurely-named "FormalParameterInitializerError"
bit of ExpressionClassifier.
This patch passes along an ExpressionClassifier when parsing class
expressions and accumulates the proper error for that case.
For the arrow function case, the fix is simply to check for the
"formal parameter initializer" error once we know we've parsed
an arrow function. The error message used for this has also
been made specific to yield expressions.
Tests are added both for the error case and the non-error cases (where
yield is used in such a position inside the class body).
BUG=v8:4966, v8:4968, v8:4974
LOG=n
Review-Url: https://codereview.chromium.org/1941823003
Cr-Commit-Position: refs/heads/master@{#35957}
Restrict the use of the `await` token as an identifier when parsing
source text as module code.
From
http://www.ecma-international.org/ecma-262/6.0/#sec-future-reserved-words:
> 11.6.2.2 Future Reserved Words
>
> The following tokens are reserved for used as keywords in future
> language extensions.
>
> Syntax
>
> FutureReservedWord ::
> enum
> await
>
> await is only treated as a FutureReservedWord when Module is the goal
> symbol of the syntactic grammar.
BUG=v8:4767
LOG=N
R=adamk@chromium.org
Review-Url: https://codereview.chromium.org/1723313002
Cr-Commit-Position: refs/heads/master@{#35914}
The first version of --harmony-for-in avoided throwing PreParser
errors in order to retain use counting. This patch threads
use_counts_ through to the PreParser to allow use counting in
the PreParser while also throwing errors for this case.
Also slightly refactored the Parser code to do a little less
code duplication.
BUG=v8:4942
LOG=y
Review URL: https://codereview.chromium.org/1913203002
Cr-Commit-Position: refs/heads/master@{#35780}
ES#sec-islabelledfunction specifies that labelled function declarations
may not occur as the body of a control flow construct such as an if
statement. This patch implements those restrictions, which also
eliminates a previous case resulting in a DCHECK failure which is now
a SyntaxError.
BUG=chromium:595309
R=adamk
LOG=Y
Review URL: https://codereview.chromium.org/1808373003
Cr-Commit-Position: refs/heads/master@{#35049}
Now that ES2015 const has shipped, in Chrome 49, legacy const declarations
are no more. This lets us remove a bunch of code from many parts of the
codebase.
In this patch, I remove parser support for generating legacy const variables
from const declarations. This also removes the special "illegal declaration"
bit from Scope, which has ripples into all compiler backends.
Also gone are any tests which relied on legacy const declarations.
Note that we do still generate a Variable in mode CONST_LEGACY in one case:
function name bindings in sloppy mode. The likely fix there is to add a new
Variable::Kind for this case and handle it appropriately for stores in each
backend, but I leave that for a later patch to make this one completely
subtractive.
Review URL: https://codereview.chromium.org/1819123002
Cr-Commit-Position: refs/heads/master@{#35002}
We don't want them to disappear from the stack traces.
BUG=v8:4698
LOG=N
Review URL: https://codereview.chromium.org/1818063002
Cr-Commit-Position: refs/heads/master@{#34957}
Modules already have a separate entrypoint into the engine (at the moment,
this is v8::ScriptCompiler::CompileModule, though that will change to
something like ParseModule). This meant that requiring a commandline flag
simply added an extra complexity burden on embedders. By removing the v8
flag, this lets embedders use their own flagging mechanism (such as d8's
"--module", or Blink's RuntimeEnabledFeatures) to control whether
modules are to be used.
Also remove old modules tests that were being skipped (since they test
very old, pre-ES2015 modules syntax).
R=littledan@chromium.org
BUG=v8:1569, chromium:594639
LOG=y
Review URL: https://codereview.chromium.org/1804693002
Cr-Commit-Position: refs/heads/master@{#34764}
Now that the destructuring flags are gone, we always call
CheckAndRewriteReferenceExpression, so unified the two methods again.
Also cleaned up the code within, e.g. removing unnecessary Scanner::Location
construction.
Review URL: https://codereview.chromium.org/1781933003
Cr-Commit-Position: refs/heads/master@{#34699}
These flags have been on by default since version 4.9, which has been
in stable Chrome for over a week now, demonstrating that they're
here to stay.
Also moved the tests out of harmony/ and into es6/.
Review URL: https://codereview.chromium.org/1776683003
Cr-Commit-Position: refs/heads/master@{#34692}
