- The global object has a reference to the current global scope chain.
Running a script adds to the chain if it contains global lexical declarations.
- Scripts are executed relative to a global, not a native context.
- Harmony let and const bindings are allocated to the innermost global context;
var and function still live on the global object.
(Lexical bindings are not reflected on the global object at all,
but that will probably change later using accessors, as for modules.)
- Compilation of scripts now needs a (global) context (previously only eval did).
- The global scope chain represents one logical scope, so collision tests take
the chain into account.
R=svenpanne@chromium.org
BUG=
Review URL: https://chromiumcodereview.appspot.com/10872084
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12398 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Specifically:
- In parser, check that all exports are defined.
- Move JSModule allocation from parser to scope resolution.
- Move JSModule linking from full codegen to scope resolution.
- Implement module accessors for exported value members.
- Allocate module contexts statically along with JSModules
(to allow static linking), but chain them when module literal is evaluated.
- Make module contexts' extension slot refer to resp. JSModule
(makes modules' ScopeInfo accessible from context).
- Some other tweaks to context handling in general.
- Make any code containing module literals (and thus embedding
static references to JSModules) non-cacheable.
This enables accessing module instance objects as expected.
Import declarations are a separate feature and do not work yet.
R=mstarzinger@chromium.org
BUG=v8:1569
TEST=
Review URL: https://chromiumcodereview.appspot.com/10690043
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12010 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Removes 6 out of 8 of our remaining unintentional failures on test262.
Also fixes treatment of inherited setters added after the fact.
Specifically:
- In the runtime, when looking for setter callbacks in the prototype chain,
also look for read-only properties. If one is found, reject (exception in
strict mode). If a proxy is found, invoke proper trap.
Note: this folds in the CanPut function from the spec and avoids an extra
lookup over the prototype chain.
- In generated code for stores, insert a test for the maps from the prototype
chain, but only up to the object where the property already exists (which
may be the object itself).
In Hydrogen, if the found property is read-only or not cacheable (e.g. a
proxy), bail out; in a stub, generate an unconditional miss (to get an
exception in strict mode).
- Add test cases and adapt existing test expectations.
R=mstarzinger@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10388047
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11694 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Constructs the (generally cyclic) graph of module instance objects
and populates their exports. Any exports other than nested modules
are currently set to 'undefined' (but already present as properties).
Details:
- Added new type JSModule for instance objects: a JSObject carrying a context.
- Statically allocate instance objects for all module literals (in parser 8-}).
- Extend interfaces to record and unify concrete instance objects,
and to support iteration over members.
- Introduce new runtime function for pushing module contexts.
- Generate code for allocating, initializing, and setting module contexts,
and for populating instance objects from module literals.
Currently, all non-module exports are still initialized with 'undefined'.
- Module aliases are resolved statically, so no special code is required.
- Make sure that code containing module constructs is never optimized
(macrofy AST node construction flag setting while we're at it).
- Add test case checking linkage.
Baseline: http://codereview.chromium.org/9722043/R=svenpanne@chromium.org,mstarzinger@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9844002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11336 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
All module expressions, and all variables that might refer to modules,
are assigned interfaces (module types) that are resolved using
unification. This is necessary to deal with the highly recursive
nature of ES6 modules, which does not allow any kind of bottom-up
strategy for resolving module names and paths.
Error messages are rudimental right now. Probably need to track
more information to make them nicer.
R=svenpanne@chromium.org
BUG=v8:1569
TEST=
Review URL: https://chromiumcodereview.appspot.com/9615009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10966 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL adds support for loading from and storing to context slots
belonging to harmony let or const bound variables. Checks for the
hole value are performed and the function is deoptimized if they fail.
The full-codegen generated code will take care of properly throwing
a reference error in these cases.
TEST=mjsunit/harmony/block-let-crankshaft.js
Review URL: http://codereview.chromium.org/8820015
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10220 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is the first CL in a series that add support for the harmony scoping
features to crankshaft. This CL specifically adds support for stack
allocated 'let' and 'const' declared variables in function scopes.
TEST=mjsunit/harmony/block-let-crankshaft.js
Review URL: http://codereview.chromium.org/8806012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10171 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The ES.next draft rev 4 in section 11.13 reads:
It is a Syntax Error if the AssignmentExpression is contained in extended code
and the LeftHandSideExpression is an Identifier that does not statically resolve
to a declarative environment record binding or if the resolved binding is an
immutable binding.
This CL adds corresponding static checks for the immutable binding case.
TEST=mjsunit/harmony/block-const-assign
Review URL: http://codereview.chromium.org/8688007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10156 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The ES.next drafts require that source code that matches the productions for
let and const bindings outside the extended mode trigger early syntax
errors. This CL adapts the parser / preparser accordingly under the harmony
scoping flag.
Summary:
* Harmony scoping flag not set: Old semantics allowing const in classic mode
with function level scope. Const binding in strict mode and let bindings in
classic and strict mode trigger early syntax errors.
* Harmony scoping is set: Use new harmony const and let in
extended mode and old const in classic mode. This is to preserve
compatibility with current web pages that already use
non-standard implementations of const. An early syntax error is
thrown on const in strict mode and on let in classic and strict
mode.
This depends on:
http://codereview.chromium.org/8562002/
TEST=mjsunit/harmony/block-early-errors.js
Review URL: http://codereview.chromium.org/8564001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10079 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL introduces a third mode next to the non-strict
(henceforth called 'classic mode') and 'strict mode'
which is called 'extended mode' as in the current
ES.next specification drafts. The extended mode is based on
the 'strict mode' and adds new functionality to it. This
means that most of the semantics of these two modes
coincide.
The 'extended mode' is entered instead of the 'strict mode'
during parsing when using the 'strict mode' directive
"use strict" and when the the harmony-scoping flag is
active. This should be changed once it is fully specified how the 'extended mode' is entered.
This change introduces a new 3 valued enum LanguageMode
(see globals.h) corresponding to the modes which is mostly
used by the frontend code. This includes the following
components:
* (Pre)Parser
* Compiler
* SharedFunctionInfo, Scope and ScopeInfo
* runtime functions: StoreContextSlot,
ResolvePossiblyDirectEval, InitializeVarGlobal,
DeclareGlobals
The old enum StrictModeFlag is still used in the backend
when the distinction between the 'strict mode' and the 'extended mode' does not matter. This includes:
* SetProperty runtime function, Delete builtin
* StoreIC and KeyedStoreIC
* StubCache
Review URL: http://codereview.chromium.org/8417035
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10062 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This implementation extends the internal ObjectHashTable to be able to
hold arbitrary objects (e.g. Smis, Strings, ...) as keys by applying
specialized hashing functions to primitive types. Equality of keys is
defined using the internal SameValue function.
R=rossberg@chromium.org
BUG=v8:1622
TEST=mjsunit/harmony/collections
Review URL: http://codereview.chromium.org/8372027
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9777 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This implements block scoped 'const' declared variables in harmony mode. They
have a temporal dead zone semantics similar to 'let' bindings, i.e. accessing
uninitialized 'const' bindings in throws a ReferenceError.
As for 'let' bindings, the semantics of 'const' bindings in global scope is not
correctly implemented yet. Furthermore assignments to 'const's are silently
ignored. Another CL will introduce treatment of those assignments as early
errors.
Review URL: http://codereview.chromium.org/7992005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9764 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The preparser has been out of sync with the parser. As a reminder, we have the
following grammer for harmony mode
Block ::
{ SourceElement* }
SourceElement ::
Statement
FunctionDeclaration
LetDeclaration
instead of
Block ::
{ Statement* }
SourceElement ::
Statement
FunctionDeclaration
The extension to allow FunctionDeclarations in statement positions in
non-strict code is still active.
Review URL: http://codereview.chromium.org/7983006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9363 ce2b1a6d-e550-0410-aec6-3dcde31c8c00