Modules now have their own local scope, represented by their own context.
Module instance objects have an accessor for every export that forwards
access to the respective slot from the module's context. (Exports that are
modules themselves, however, are simple data properties.)
All modules have a _hosting_ scope/context, which (currently) is the
(innermost) enclosing global scope. To deal with recursion, nested modules
are hosted by the same scope as global ones.
For every (global or nested) module literal, the hosting context has an
internal slot that points directly to the respective module context. This
enables quick access to (statically resolved) module members by 2-dimensional
access through the hosting context. For example,
module A {
let x;
module B { let y; }
}
module C { let z; }
allocates contexts as follows:
[header| .A | .B | .C | A | C ] (global)
| | |
| | +-- [header| z ] (module)
| |
| +------- [header| y ] (module)
|
+------------ [header| x | B ] (module)
Here, .A, .B, .C are the internal slots pointing to the hosted module
contexts, whereas A, B, C hold the actual instance objects (note that every
module context also points to the respective instance object through its
extension slot in the header).
To deal with arbitrary recursion and aliases between modules,
they are created and initialized in several stages. Each stage applies to
all modules in the hosting global scope, including nested ones.
1. Allocate: for each module _literal_, allocate the module contexts and
respective instance object and wire them up. This happens in the
PushModuleContext runtime function, as generated by AllocateModules
(invoked by VisitDeclarations in the hosting scope).
2. Bind: for each module _declaration_ (i.e. literals as well as aliases),
assign the respective instance object to respective local variables. This
happens in VisitModuleDeclaration, and uses the instance objects created
in the previous stage.
For each module _literal_, this phase also constructs a module descriptor
for the next stage. This happens in VisitModuleLiteral.
3. Populate: invoke the DeclareModules runtime function to populate each
_instance_ object with accessors for it exports. This is generated by
DeclareModules (invoked by VisitDeclarations in the hosting scope again),
and uses the descriptors generated in the previous stage.
4. Initialize: execute the module bodies (and other code) in sequence. This
happens by the separate statements generated for module bodies. To reenter
the module scopes properly, the parser inserted ModuleStatements.
R=mstarzinger@chromium.org,svenpanne@chromium.org
BUG=
Review URL: https://codereview.chromium.org/11093074
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13033 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
These were erroneously disabled because they were expecting indexed properties to be of Number type when appearing as the "name" in change records. But the "name" property will always be a string. Fixed assertRecordsEqual() to enforce this in expectations.
BUG=v8:2409
Review URL: https://codereview.chromium.org/11280105
Patch from Adam Klein <adamk@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13027 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The previous implementation in Accessors::ArraySetLength failed when array length was set through StoreIC_ArrayLength. But that stub and the accessor both delegate to JSArray::SetElementsLength, so moving the code there allows notifications to be sent in both cases.
Review URL: https://codereview.chromium.org/11275292
Patch from Adam Klein <adamk@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12962 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In more detail:
- Set observation bit for observed objects (and make NormalizedMapCache respect it).
- Mutation of observed objects is always delegated from ICs to runtime.
- Introduce JS runtime function for notifying generated changes.
- Invoke this function in the appropriate places (including some local refactoring).
- Inclusion of oldValue field is not yet implemented, nor element properties.
Also, shortened flag to --harmony-observation.
R=verwaest@chromium.org
BUG=
Review URL: https://codereview.chromium.org/11347037
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12867 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- 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
