During parsing functions are analyzed for statements of the form this.x = ...;. These assignments are categorized in two types: simple and non simple. The simple ones are where the right hand side is known to be either a constant or an argument to the function. If a function only contains statements of this type the property names are collected and for the simple assignments the index of the argument or the constant value assigned are stored as well.
When the initial map for a function is created and the function consists of only this type of assignemnts the initial map is created with a descriptor array describing these properties which will be known to always exist in an object created from the function.
The information on this property assignments is not collected during pre-parsing so if compiling using pre-parse data these optimization hints are not available.
Next step will be to use the information collected for the simple assignments to generate constructor code which will create and initialize the object from this information without calling the code for the function.
Review URL: http://codereview.chromium.org/172088
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2710 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
space is similar to map space in that it has fixed-size objects. A
common superclass for a space with fixed size objects is used for the
map space and cell space.
Allocate all cells in cell space. Handle it during all GCs. Modify
the free-list node representation (so that the size is not at a fixed
offset in all cells) to allow two-pointer free-list nodes. Clean up
some stuff in the MC collector.
Review URL: http://codereview.chromium.org/155211
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2411 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
submitted in revisions 2093, 2094, 2099, and 2106.
There's no evidence that supports that these changes
should be the cause of the unexplained performance
regressions on the intl2 and DHTML page cyclers.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2109 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
immediately if holder has this property or saves binary search on holder if
property doesn't belong to holder. Of course, in the cases when named getter
returns nothing.
That gives ~20% for dom benchmark/Document Object String Get, speeds up overall
dom_perf (not dramatically) and overall score for peacekeeper. Strange, but DOM
part of peacekeepr runs somewhat slower.
Review URL: http://codereview.chromium.org/118118
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2093 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
called from within a loop or not. In the past we lost the
information if a call site went megamorphic before a lazily
compiled callee was called for the first time. Now we track
that correctly (this is an issue that affects richards).
We still don't manage to track the in-loop state through a
constructor call, since constructor calls use LoadICs instead
of CallICs. This issue affects delta-blue. So in this patch
we assume that lazy compilations that don't happen through a
CallIC happen from inside a loop. I have an idea to fix this
but this patch is big enough already.
With our improved tracking of in-loop state I have switched
off the inlining of in-object loads for code that is not in
a loop. This benefits compile speed. One issue is that
eagerly compiled code now doesn't get the in-object loads
inlined. We need to eagerly compile less code to fix this.
Review URL: http://codereview.chromium.org/115744
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2046 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
resource to NULL when removing it from the symbol table. This makes
sure that the debugger can recognize the external string as being
"deleted". Now, whenever an external resource is deleted, the
resource pointer is set to NULL.
This is really a workaround of a debugger problem. We need to make
sure that the debugger only finds scripts in the heap that are
actually live.
Review URL: http://codereview.chromium.org/69029
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1734 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Currently function name inference is wired with AST optimization pass to avoid introducing another pass over AST. A better solution would be to rewrite AST visitors so they can be naturally combined together in a single pass, as their current implementation doesn't allow it.
For examples of cases where function names can be inferred, see the tests file.
Review URL: http://codereview.chromium.org/62146
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1696 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
operation. I have another version of this change that does not remove the
special inline caches for difference sized strings. The other version is ever
so slightly faster, but the nice thing about this version is that it removes
253 lines of code.
Review URL: http://codereview.chromium.org/8187
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@603 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
If a map has descendents in the map transition tree that are alive,
it is kept. Only maps such that they and all their descendants
have no live objects are collected. This happens in mark-sweep and
mark-compact garbage collections.
Review URL: http://codereview.chromium.org/8099
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@601 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
- Changed WeakReferenceCallback to take a Persistent<Value> instead of
a Persistent<Object>.
- Removed Message::GetUnderline and Message::GetScriptData.
- Added Value::IsDate, Date::Cast and Date::Value.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@564 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
underlying string representation of the two strings involved.
- Renamed ascii and two byte string classes to sequential ascii and
sequential two byte, and renamed IsAscii and friends to
IsAsciiRepresentation. This is to make a clear distinction between
strings with an ascii/two-byte representation, of which there is
four, and flat sequential ascii/two-byte string.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@474 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
are always odd if the bit-field bits are included.
Modified a couple of debugger tests that relied on the ordering of
elements in descriptor arrays. Descriptor arrays are sorted by
hash-code values, so the order changes if we change the hash code.
Review URL: http://codereview.chromium.org/6489
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@440 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
Update the lookup and update code for code caches to deal with deleted
elements.
Do not clear the code cache for the builtins object. If there was a
matching element in the code cache, we would have hit the monomorphic
prototype failure case and removed it.
Review URL: http://codereview.chromium.org/3140
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@340 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
occured. After a monomorphic prototype failure has been detected,
other monomorphic inline caches for the same type will have a code
object in the map's code cache which is not the current target. We
recognize this case and use the code object that is in the cache
instead of going megamorphic.
Review URL: http://codereview.chromium.org/2928
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@331 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
it for scripts too. In the context of Chromium, this should
have a very positive impact on memory consumption for web apps
that run multiple tabs from the same domain with a lot of the
same JavaScript code.
For now, the cache retirement policy is really simple:
Whenever a mark-sweep collection is started we clear the
cache. This guarantees that this change will not have a
huge negative impact on memory consumption, but it may
not be ideal. We should consider a more sophisticated LRU
scheme.
Review URL: http://codereview.chromium.org/1933
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@270 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The cache is a hashtable that takes String as key and JSFunction as the value.
Caches are cleared before mark-compact GC's.
Currently I don't put caps on cache size, string size, etc.
This cuts date-parse-totfe.js runtime by half.
Review URL: http://codereview.chromium.org/457
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@173 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
KeyedLoadIC::GenerateGeneric (on IA32), and the same on ARM.
Re-assignmed FIRST_JS_OBJECT_TYPE to JS_VALUE_TYPE.
Also changed JS_OBJECT_TYPE to FIRST_JS_OBJECT_TYPE in several places where
FIRST_JS_OBJECT_TYPE is intended.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@113 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
Added a few samples and support for building them. The samples include a simple shell that can be used to benchmark and test V8.
Changed V8::GetVersion to return the version as a string.
Added source for lazily loaded scripts to snapshots and made serialization non-destructive.
Improved ARM support by fixing the write barrier code to use aligned loads and stores and by removing premature locals optimization that relied on broken support for callee-saved registers (removed).
Refactored the code for marking live objects during garbage collection and the code for allocating objects in paged spaces. Introduced an abstraction for the map word of a heap-allocated object and changed the memory allocator to allocate executable memory only for spaces that may contain code objects.
Moved StringBuilder to utils.h and ScopedLock to platform.h, where they can be used by debugging and logging modules. Added thread-safe message queues for dealing with debugger events.
Fixed the source code reported by toString for certain builtin empty functions and made sure that the prototype property of a function is enumerable.
Improved performance of converting values to condition flags in generated code.
Merged disassembler-{arch} files.
git-svn-id: http://v8.googlecode.com/svn/trunk@8 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
