Added highly efficient Object::SetAlignedPointerInInternalField and
Object::GetAlignedPointerFromInternalField functions for 2-byte-aligned
pointers. Their non-aligned counterparts Object::GetPointerFromInternalField and
Object::SetPointerInInternalField are now deprecated utility functions.
External is now a true Value again, with New/Value/Cast using a JSObject with an
internal field containing a Foreign. External::Wrap, and External::Unwrap are now
deprecated utility functions.
Added Context::GetEmbedderData and Context::SetEmbedderData. Deprecated
Context::GetData and Context::SetData, these are now only wrappers to access
internal field 0.
Added highly efficient Context::SetAlignedPointerInEmbedderData and
Context::GetAlignedPointerFromEmbedderData functions for 2-byte-aligned
pointers.
Review URL: https://codereview.chromium.org/11190050
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12849 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in anticipation of the upcoming lexical global scope.
Mostly automatised as:
for FILE in `egrep -ril "global[ _]?context" src test/cctest`
do
echo $FILE
sed "s/Global context/Native context/g" <$FILE >$FILE.0
sed "s/global context/native context/g" <$FILE.0 >$FILE.1
sed "s/global_context/native_context/g" <$FILE.1 >$FILE.2
sed "s/GLOBAL_CONTEXT/NATIVE_CONTEXT/g" <$FILE.2 >$FILE.3
sed "s/GlobalContext/NativeContext/g" <$FILE.3 >$FILE
rm $FILE.[0-9]
done
R=mstarzinger@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10832342
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12325 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Now a map points to a transition array which contains the descriptor array. The descriptor array is now immutable. The next step is to share the descriptor array with all back-pointed maps as long as there is a single line of extension. Maps that require a descriptor array but don't need transitions will still need a pseudo-empty transition array to contain the descriptor array.
Review URL: https://chromiumcodereview.appspot.com/10816005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12298 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Using insertion-sort won't have too much of an overhead for the short arrays for bootstrapping (which are probably snapshot anyway).
CopyAppendCallbackDescriptors was extending and sorting the array in a loop. By using an append that inserts at the right position we do not need to resort in each iteration.
Additionally remove Sort and rename SortUnchecked to Sort. The IsSortedNoDuplicates check is moved into InitializeDescriptor.
Review URL: https://chromiumcodereview.appspot.com/10808011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12136 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
AccessorPair related transitions are now also stored as single map links, simplifying the code that handles transitions. AccessorPairs can now be shared between descriptor arrays, since they can only be mutated after another transition anyway; during which the pair is copied before writing.
Review URL: https://chromiumcodereview.appspot.com/10784014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12097 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The LastAdded points to the descriptor that was last added to the array. From the descriptor we can deduce the NextEnumerationIndex. This allows us to quickly find the property that we are transitioning to, which is necessary for transition-intensive code, eg JSON parsing.
Review URL: https://chromiumcodereview.appspot.com/10695120
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12042 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
In this design maps contain descriptor arrays, which in turn can contain transition arrays. If transitions are needed when no descriptor array is present, a descriptor array without real descriptors is inserted just so it can point at the transition array.
The transition array does not contain details about the field it transitions to. In order to weed out transitions to FIELDs from CONSTANT_FUNCTION (what used to be MAP_TRANSITION vs CONSTANT_TRANSITION), the transition needs to be followed and the details need to be looked up in the target map. CALLBACKS transitions are still easy to recognize since the transition targets are stored as an AccessorPair containing the maps, rather than the maps directly.
Currently AccessorPairs containing a transition and an accessor are shared between the descriptor array and the transition array. This simplifies lookup since we only have to look in one of both arrays. This will change in subsequent revisions, when descriptor arrays will become shared between multiple maps, since transitions cannot be shared.
Review URL: https://chromiumcodereview.appspot.com/10697015
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11994 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Instead of overwriting non-live transitions with NULL_DESCRIPTORs, we remove them from the array by compacting the array (shifting live values to the left) and in-place trimming the array. If the final descriptor array contains no live values (only contained transitions which are now all cleared), we move bit_field3 back from the descriptor array to the map. The descriptor array itself will be collected in the next GC.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10575032
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11922 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
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
Replaced FIRST_PHANTOM_PROPERTY_TYPE by a predicate. Removed the (hopefully)
last default cases for switches on PropertyType. Benchmarks show that both
changes are performace-neutral.
Now every value of PropertyType should either be handled by an explicit case in
a switch or by an equality operator. Therefore, the C++ compiler should finally
be able to tell us which places to touch when changing PropertyType.
Review URL: http://codereview.chromium.org/8506004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9930 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
In some special (but probably very common) cases we can do better than loading
from a global cell for these global properties by emitting the corresponding
constant directly. This opens up opportunities for further improvements, coming
in a separate CL...
Review URL: http://codereview.chromium.org/7992002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9409 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Due to issues relating mostly to chrome extensions we have lately been
running into OOMs that are caused by our executable space running
out. This change introduces flushing of code from regexps if we have
not used the code for 5 mark sweeps.
The approach is different from the normal function code flusing. Here
we make a copy of the code inside the data array, and exchange the
original code with a smi determined by the sweep_generation (a new
heap variable increased everytime we do mark sweep/compact). If we
encounter a smi in EnsureCompiled we simply reinstate the code
object. If, in the marking phase of mark sweep, we find a regexp that
already have a smi in the code field, and this is more than 5
generations old we flush the code from the saved index.
Review URL: http://codereview.chromium.org/7282026
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8532 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Before, they had no extra slots and an extension object with one named
property. Now, they use the extension slot for the property name and have
an extra slot for the thrown object. This increases the size of the context
itself, but removes overall allocation and eliminates a level of indirection.
R=ager@chromium.org
Review URL: http://codereview.chromium.org/7152002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8277 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Introduce separate maps for function and with contexts. Use the function
context map for testing whether a context is a function context (global
contexts are no longer function contexts).
Split the paths for allocating with and catch contexts.
Rename some functions. Generally refactor code to make it simpler.
R=ager@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/7003058
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8231 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The current json parser and scanner inherits fromt he normal scanners and parsers,
which are more complicated than we need for parsing json.
The supplied scanner works directly on the string supplied and has a
fast case mode for scanning only ascii characters (it will simply
create a substring or a symbol directly from the existing string). To
allow for creating symbols from a substring I have added a
SubStringAsciiSymbolKey that creates the hash based from our string
without extracting the sub-string. In case we need to add the symbol
it simply creates the symbol directly from the characters inside the
given string.
Review URL: http://codereview.chromium.org/7039037
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8029 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
1) Add new type JSProxy for representing proxy objects.
Currently devoid of functionality, i.e., all properties are undefined.
2) Some rudimentary global $Proxy functions to create proxies.
Next step: Hook up getProperty and getOwnProperty handlers. Will probably
require introducing a new LookupResult type, which is a mixture of
INTERCEPTOR (handles any property) and CALLBACK (calls back to JS).
Can we unify this somehow?
TODO: Should probably rename existing Proxy type to something like
"Foreign", to avoid confusion.
Review URL: http://codereview.chromium.org/6932068
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7887 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Worth mentioning:
- Specialized versions of pixel array and store/loads inside the generic stubs have been removed, since to have parity for all external arrays, 8 different versions would have to be inlined/checked.
- There's a new constant in v8.h for external arrays with pixel array elements.
Review URL: http://codereview.chromium.org/6546036
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7106 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Non-moveable code-stube are allocated in large object space. They are only required on ARM where the different C-entry stubs are required to never move.
This gets rid of pre-computing these stubs and hope that they never move. Also for crankshaft the C-entry stub which saved doubles is not generated in the snapshot so it ends up being generated at runtime and potentially move.
Review URL: http://codereview.chromium.org/6626072
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7097 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in allowing more flexible compilation and to simplify builtins lookup.
This changes a number of places where code objects are assigned to
SharedFunctionInfo objects to also assign this code object to the
JSFunction. In addition, the code flushing is changed slightly to
accomodate this (we need to flush the code from functions pointing to
SharedFunctionInfo objects that has already been flushed).
Review URL: http://codereview.chromium.org/3120006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5233 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The static ScopeInfo members moved into this class.
The new class is named ScopeInfoObject which I am not proud of,
better ideas are very welcome.
Also got rid of the sentinels in the serialized scope info which saves 3 words per function
and is not slower.
Review URL: http://codereview.chromium.org/2908009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5067 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Use virtually dispatched specialized scavengers instead of single generic ScavengeObjectSlow implementation.
Rollback of r5041 with assertion checking callback alignment removed. Map space is iterated in a special fashion during scavenges so special callback alignment is not required.
Review URL: http://codereview.chromium.org/2950003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5047 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
A potential issue with this change is creating lots of maps when
objects flip between fast/slow elements modes. We could add special
transitions to avoid this. Yet testing this on our benchmarks, gmail,
and wave seems to indicate that this is not a real problem.
Review URL: http://codereview.chromium.org/2870018
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4941 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in particular).
* Called function is passed on the stack instead of
using a static variable.
* Builtins that don't need the called function don't
get it.
* Made is_construct statically known to HandleApiCall
by setting custom construct stub for API functions.
Review URL: http://codereview.chromium.org/536065
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3613 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
For scripts originating from a call to eval the Script object used to hold a reference to the function from where the eval was called together with the code offset within that function of the eval call. This is used by the stack trace and is part of the debugger protocol. In order to avoid storing the function the script, the position within the script and the name of the function calling eval is stored instead. This avoids holding context dependent objects in the script object.
The calculation of the position of the eval in the script holding the eval is now done when the eval script is compiled as it is not possible to postpone this unless a reference is kept to the generated code for the function calling eval.
BUG=http://code.google.com/p/v8/issues/detail?id=528
TEST=cctest/test-api/Regress528
Review URL: http://codereview.chromium.org/450034
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3393 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Storing a JSArray in the Script object could cause an indirect reference from the compilation cache to a global object to be created. Now the line ends are only stored as a FixedArrya and when that is needed in JavaScript a JSArray copy is created. Changed some of the JavaScript code to cache the line ends in a local variable for better performance.
BUG=http://code.google.com/p/v8/issues/detail?id=528
TEST=test/test-api/Bug528
Review URL: http://codereview.chromium.org/434117
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3374 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
specification under development. The optimizations are patterned after
those previously done for CanvasPixelArray. This CL adds all of the
necessary framework but continues to use the generic KeyedLoadIC and
KeyedStoreIC code, to create a baseline for benchmarking purposes. The
next CL will add the optimized ICs to ic-ia32.cc and ic-x64.cc.
These new CanvasArray types have different semantics than
CanvasPixelArray; out-of-range values are clamped via C cast
semantics, which is cheaper than the clamping behavior specified by
CanvasPixelArray. Out-of-range indices raise exceptions instead of
being silently ignored.
As part of this work, pulled FloatingPointHelper::AllocateHeapNumber
up to MacroAssembler on ia32 and x64 platforms. Slightly refactored
KeyedLoadIC and KeyedStoreIC. Fixed encoding for fistp_d on x64 and
added a few more instructions that are needed for the new ICs. The
test cases in test-api.cc have been verified by hand to exercise all
of the generated code paths in the forthcoming specialized ICs.
Review URL: http://codereview.chromium.org/293023
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3096 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The abstractions have led to bugs because it looks like descriptor
streams are GC safe but they are not.
I have moved the descriptor stream helper functions to descriptor
arrays and I find most of the code just as readable now as it was
before.
Review URL: http://codereview.chromium.org/149458
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2428 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Scripts now have a compilation type which can be host, eval or JSON. Host scripts are compiled through the API, eval scripts are compiled through call to evan and JSON scripts are compiled as a result of calling JSON.parse.
For scripts scripts compiled through eval the JavaScript function in top of the stack and the pc offset into the code is stored in the script object. This makes it possible to calculate the source position of the eval call later when requested. This information can be obtained through the script mirror object and is part of the script mirror JSON serialization for the debugger protocol.
Moved the enumeration ScripType into class Script and remamed to Type. The new compilation type enumeration is also inside the class Script.
This information is now shown when using the scripts command in he developer shell debugger.
Review URL: http://codereview.chromium.org/119108
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2119 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This issue was raised by Brett Wilson while reviewing my changelist for readability. Craig Silverstein (one of C++ SG maintainers) confirmed that we should declare one namespace per line. Our way of namespaces closing seems not violating style guides (there is no clear agreement on it), so I left it intact.
Review URL: http://codereview.chromium.org/115756
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2038 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Added a simple initial version of a context mirror object which just holds the user data from the context, and does not preserve handle identity.
A script object now holds a reference to the custom data from the context it was compiled in. This data is included in the debugger protocol for scripts.
Changed the serialization for the scripts command to use the mirror objects instaed of custom serialization. This included passing options from the debugger request to the serializer for including the full source of scripts in the response.
Review URL: http://codereview.chromium.org/111001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1877 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
ENABLE_DEBUGGER_SUPPORT is enabled by default unless it is on Android platform.
On Android platform, it can also enabled by passing -DENABLE_DEBUGGER_SUPPORT flag to the compiler.
This should not affect any existing build (I hope, cross my fingers) except the build in real Android environment (in other word, it only affects me now).
There are lot of room for code refactoring in stead of using #ifdef all over the place. I will leave this to v8 folks.
Review URL: http://codereview.chromium.org/77035
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1745 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Changed the script break points to be able to handle both break points based on script names and script ids. When break points are set through a script id the position is relative to the script itself. This is different from the script break points set through script names where the line/coulmn offset is taken into account.
This has the side effect that function break points are not converted into script break points for named scripts.
Show the script id in the D8 shell debugger when listing all scripts using the 'scripts' command.
Review URL: http://codereview.chromium.org/40317
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1468 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
1418, and 1419 from bleeding_edge until we have a fix
for the crashers we see on the distributed test infra-
structure.
We know that revision 1383 is causing issues, but I
had to revert some of the other recent RegExp changes
in order to get this part out.
Review URL: http://codereview.chromium.org/39186
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1429 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Thus, instead of the following profiler records:
1.5% 1.5% LazyCompile: <anonymous>
we'll now have these:
1.5% 1.5% LazyCompile: <anonymous> richards.js:309
Basically, I translated two functions from messages.js into C++.
In the next CL I will update messages.js to use added native functions.
Review URL: http://codereview.chromium.org/19537
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1216 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
through the API. This allows us to verify state on entry through the API.
In this change verification in the API entry is checking that the current
thread holds the V8 lock when a HandleScope is instantiated if a v8::Locker
has ever been used by the V8 instance.
Review URL: http://codereview.chromium.org/18707
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1140 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This can lead to large objects which wastes a lot of space if we normalize properties. We therfore clear the inobject properties when normalizing properties. This is done by adjusting the instance size in the new map and overwriting the inobject properties with a filler.
Review URL: http://codereview.chromium.org/17308
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1051 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The performance of Array::concat is critical of jQuery benchmark from
http://www.dromaeo.com. Our current implementation in JavaScript is very
generic and is several times slower than JSC and SpiderMonkey.
Re-implement Array::concat in C++ to take advantage of underlying implementation
details. This cuts dom-travesal-jquery execution time by half.
We may want to move Array specific implementation into a separate source file,
say jsarray.cc.
Review URL: http://codereview.chromium.org/7990
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@625 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Changed the structure of regexp objects from having two internal
fields to having a single field containing a fixed array, since it's
easier to store the whole fixed array in the cache.
- Move printing of the command to after printing std{err,out} in the
compact progress indicators in the test framework.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@579 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Here is a description of the background and design of split window in Chrome and V8:
https://docs.google.com/a/google.com/Doc?id=chhjkpg_47fwddxbfr
This change list splits the window object into two parts: 1) an inner window object used as the global object of contexts; 2) an outer window object exposed to JavaScript and accessible by the name 'window'. Firefox did it awhile ago, here are some discussions: https://wiki.mozilla.org/Gecko:SplitWindow. One additional benefit of splitting window in Chrome is that accessing global variables don't need security checks anymore, it can improve applications that use many global variables.
V8 support of split window:
There are a small number of changes on V8 api to support split window:
Security context is removed from V8, so does related API functions;
A global object can be detached from its context and reused by a new context;
Access checks on an object template can be turned on/off by default;
An object can turn on its access checks later;
V8 has a new object type, ApiGlobalObject, which is the outer window object type. The existing JSGlobalObject becomes the inner window object type. Security checks are moved from JSGlobalObject to ApiGlobalObject. ApiGlobalObject is the one exposed to JavaScript, it is accessible through Context::Global(). ApiGlobalObject's prototype is set to JSGlobalObject so that property lookups are forwarded to JSGlobalObject. ApiGlobalObject forwards all other property access requests to JSGlobalObject, such as SetProperty, DeleteProperty, etc.
Security token is moved to a global context, and ApiGlobalObject has a reference to its global context. JSGlobalObject has a reference to its global context as well. When accessing properties on a global object in JavaScript, the domain security check is performed by comparing the security token of the lexical context (Top::global_context()) to the token of global object's context. The check is only needed when the receiver is a window object, such as 'window.document'. Accessing global variables, such as 'var foo = 3; foo' does not need checks because the receiver is the inner window object.
When an outer window is detached from its global context (when a frame navigates away from a page), it is completely detached from the inner window. A new context is created for the new page, and the outer global object is reused. At this point, the access check on the DOMWindow wrapper of the old context is turned on. The code in old context is still able to access DOMWindow properties, but it has to go through domain security checks.
It is debatable on how to implement the outer window object. Currently each property access function has to check if the receiver is ApiGlobalObject type. This approach might be error-prone that one may forget to check the receiver when adding new functions. It is unlikely a performance issue because accessing global variables are more common than 'window.foo' style coding.
I am still working on the ARM port, and I'd like to hear comments and suggestions on the best way to support it in V8.
Review URL: http://codereview.chromium.org/7366
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@540 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
canonicalize maps for object literals. JSON objects
with the same set of properties names will then
share the same map.
This reduces the amount of generated code associated
with object literals.
- Added a flag canonicalize_object_literal_maps.
(default true)
- Changed the format of a function's literal array.
Only the global context is now stored in the literal prefix.
Review URL: http://codereview.chromium.org/4078
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@371 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* Make old_data_space non-executable on OSs and hardware that support it.
* Rename old_space to old_pointer_space (can contain pointers, esp. to new space).
* Ensure that individual pages allocated for old_space are only executable when
they are for code objects.
* Ensure Space::Setup can cope with non-aligned memory.
* Make some methods on Spaces virtual. Make a way to iterate over all spaces.
* Replace executability flag with Executability enum in order to make intent at
call site clearer.
* Fix serialization/deserialization to allocate write barrier memory for large
arrays.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@165 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
method ensures that there are no allocations during the setup.
This fixes test breakage on Linux in debug mode where allocation
happened while the debug info object was not fully set up making
verify heap unhappy.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@70 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Fixed mozilla test breakage caused by python's obscure module
loading rules.
- Made sure test.py propagates test failures out as the exit code of
the script.
- Remove runtime calls to get number constants. Remove Heap roots for
some special numbers.
- Fix typo in accessors.h.
- Changes CopyMap to not copy descriptors. Adds
CopyMapRemoveTransitions that copies non-transition descriptors.
Changes interface of DescriptorArray::Copy operations to simplify
them.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@21 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Added better test support.
Added load, quit and version functions to the shell sample so it's easier to run benchmarks and tests.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In the shell sample don't print the result of executing a script, only
evaluating expressions.
Fixed issue when building samples on Windows using a shared V8
library. Added visibility option on Linux build which makes the
generated library 18% smaller.
Changed build system to accept multiple build modes in one build and
generate seperate objects, libraries and executables for each mode.
Removed deferred negation optimization (a * -b => -(a * b)) since this
visibly changes operand conversion order.
Improved parsing performance by introducing stack guard in preparsing.
Without a stack guard preparsing always bails out with stack overflow.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Cleaned up ARM version by removing top of stack caching and by introducing push/pop elimination.
Cleaned up the way runtime functions are called to allow runtime calls with no arguments.
Changed Windows build options to make sure that exceptions are disabled and that optimization flags are enabled.
Added first version of Visual Studio project files.
git-svn-id: http://v8.googlecode.com/svn/trunk@13 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Added propagation of stack overflow exceptions that occur while compiling nested functions.
Improved debugger with support for recursive break points and handling of exceptions that occur in the debugger JavaScript code.
Renamed GetInternal to GetInternalField and SetInternal to SetInternalField in the API and moved InternalFieldCount and SetInternalFieldCount from FunctionTemplate to ObjectTemplate.
git-svn-id: http://v8.googlecode.com/svn/trunk@5 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
