The approach in this change is to handle the unwrapping/wrapping of the global object transparently with respect to the JS implementation of Object.observe. An alternate approach would be to add a runtime method like %IsJSGlobalProxy and %UnwrapJSGlobalProxy, but it seems ugly to give JS (even implementation JS) access to the unwrapped global.
BUG=v8:2409
Review URL: https://codereview.chromium.org/11414094
Patch from Adam Klein <adamk@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13142 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This changes how FunctionTemplate interprets a Signature that specifies
compatible receivers and arguments. Only the hidden prototype chain will
be considered when searching for compatible receivers. This prevents
JavaScript from modifying the inheritance relationship set up by the
embedder.
R=rossberg@chromium.org
BUG=v8:2268
TEST=cctest/test-api
Review URL: https://codereview.chromium.org/11308197
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13131 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
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
- perform CPU profiler sampling in the sampler thread as we used to;
- skip sampling in the sampling thread if processing thread is running;
- only install SIGPROF handler when CPU profiling is enabled.
BUG=v8:2364
Review URL: https://codereview.chromium.org/11231002
Patch from Sergey Rogulenko <rogulenko@google.com> and Andrey Kosyakov <caseq@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12985 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
To preserve ordering guarantees during end-of-turn delivery, Object.deliverChangeRecords needs to remove the delivered-to observer from the list of active observers.
The added test demonstrates this behavior.
Review URL: https://codereview.chromium.org/11410046
Patch from Adam Klein <adamk@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12951 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL has two parts: the first is the logic itself, whereby each observer callback is assigned
a "priority" number the first time it's passed as an observer to Object.observe(), and that
priority is used to determine the order of delivery.
The second part invokes the above logic as part of the API, when the JS stack winds down to
zero.
Added several tests via the API, as the delivery logic isn't testable from a JS test
(it runs after such a test would exit).
Review URL: https://codereview.chromium.org/11266011
Patch from Adam Klein <adamk@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12902 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This requires adding a new JSObject to the strong root list and populating it from
object-observe.js. The main other change is that we now directly use ObjectHashTable
from JS rather than using WeakMap, since using the latter would end up leaking whichever
Context initialized that observation state.
Added a test via the API showing that different contexts all end up working on the same state.
Review URL: https://codereview.chromium.org/11274014
Patch from Adam Klein <adamk@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12873 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
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
This enables code flushing even with incremental marking enabled and
fully shares the function link field in JSFunctions between candidates
for code flushing and the optimized functions list. If a candidate for
code flushing gets optimized, it will be evicted from the candidates
list.
R=ulan@chromium.org
BUG=v8:1609
Review URL: https://codereview.chromium.org/11140025
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12796 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In WebKit, we have a small integer cache because calling v8::Integer::New is
slow. This patch adds a faster API for creating integers that requires the
caller to supply the v8::Isolate, saving us the work of looking up the isolate
in thread-local storage.
BUG=
Review URL: https://codereview.chromium.org/11212004
Patch from Adam Barth <abarth@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12773 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This API lets the embedder enumerate handles that have class ids. WebKit will
use this feature during garbage collection to compute object groups for DOM
nodes. Previously, we kept a list of DOM nodes on the WebKit side, but that
list is redundant with the global handles list in V8.
Review URL: https://codereview.chromium.org/11190011
Patch from Adam Barth <abarth@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12750 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
the speed of deserializing code. The current startup
time improvement for V8 is around 6%, but code deserialization
is speeded up disproportionately, and we will soon have more
code in the snapshot.
* Removed support for deserializing into large object space.
The regular pages are 1Mbyte now and that is plenty. This
is a big simplification.
* Instead of reserving space for the snapshot we actually
allocate it now. This removes some special casing from
the memory management and simplifies deserialization since
we are just bumping a pointer rather than calling the
normal allocation routines during deserialization.
* Record in the snapshot how much we need to boot up and
allocate it instead of just assuming that allocations in
a new VM will always be linear.
* In the snapshot we always address an object as a negative
offset from the current allocation point. We used to
sometimes address from the start of the deserialized data,
but this is less useful now that we have good support for
roots and repetitions in the deserialization data.
* Code objects were previously deserialized (like other
objects) by alternating raw data (deserialized with memcpy)
and pointers (to external references, other objects, etc.).
Now we deserialize code objects with a single memcpy,
followed by a series of skips and pointers that partially
overwrite the code we memcopied out of the snapshot.
The skips are sometimes merged into the following
instruction in the deserialization data to reduce dispatch
time.
* Integers in the snapshot were stored in a variable length
format that gives a compact representation for small positive
integers. This is still the case, but the new encoding can
be decoded without branches or conditional instructions,
which is faster on a modern CPU.
Review URL: https://chromiumcodereview.appspot.com/10918067
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12505 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL adds multiple things:
Transition arrays do not directly point at their descriptor array anymore, but rather do so via an indirect pointer (a JSGlobalPropertyCell).
An ownership bit is added to maps indicating whether it owns its own descriptor array or not.
Maps owning a descriptor array can pass on ownership if a transition from that map is generated; but only if the descriptor array stays exactly the same; or if a descriptor is added.
Maps that don't have ownership get ownership back if their direct child to which ownership was passed is cleared in ClearNonLiveTransitions.
To detect which descriptors in an array are valid, each map knows its own NumberOfOwnDescriptors. Since the descriptors are sorted in order of addition, if we search and find a descriptor with index bigger than this number, it is not valid for the given map.
We currently still build up an enumeration cache (although this may disappear). The enumeration cache is always built for the entire descriptor array, even if not all descriptors are owned by the map. Once a descriptor array has an enumeration cache for a given map; this invariant will always be true, even if the descriptor array was extended. The extended array will inherit the enumeration cache from the smaller descriptor array. If a map with more descriptors needs an enumeration cache, it's EnumLength will still be set to invalid, so it will have to recompute the enumeration cache. This new cache will also be valid for smaller maps since they have their own enumlength; and use this to loop over the cache. If the EnumLength is still invalid, but there is already a cache present that is big enough; we just initialize the EnumLength field for the map.
When we apply ClearNonLiveTransitions and descriptor ownership is passed back to a parent map, the descriptor array is trimmed in-place and resorted. At the same time, the enumeration cache is trimmed in-place.
Only transition arrays contain descriptor arrays. If we transition to a map and pass ownership of the descriptor array along, the child map will not store the descriptor array it owns. Rather its parent will keep the pointer. So for every leaf-map, we find the descriptor array by following the back pointer, reading out the transition array, and fetching the descriptor array from the JSGlobalPropertyCell. If a map has a transition array, we fetch it from there. If a map has undefined as its back-pointer and has no transition array; it is considered to have an empty descriptor array.
When we modify properties, we cannot share the descriptor array. To accommodate this, the child map will get its own transition array; even if there are not necessarily any transitions leaving from the child map. This is necessary since it's the only way to store its own descriptor array.
Review URL: https://chromiumcodereview.appspot.com/10909007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12492 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
