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
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
ExtendStorage did not work with keyed store IC.
- Reduced instructions generated when performing a tail call to
kSharedStoreIC_ExtendStorage
- Moved test/mjsunit/bugs/bug-109.js
to test/mjsunit/keyed-storage-extend.js
Review URL: http://codereview.chromium.org/6526
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@455 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Simplified frame entry and frame exit code.
- Added ArgumentsAdaptorTrampoline and check for matching argument counts in the InvokePrologue.
- Removed definition and uses of USE_OLD_CALLING_CONVENTIONS.
- Changed MacroAssembler::InvokeBuiltin to match ia32 version.
- Start introducing convenience instructions in the ARM assembler as needed. These instructions take all Register parameters to avoid extra typing of "Operand(reg)".
To keep the architectures in sync these changes have been made to the ia32 files:
- Changed MacroAssembler::EnterFrame(StackFrame::Type type) to MacroAssembler::EnterInternalFrame().
These parts are still missing:
- unimplemented: Builtins::Generate_FunctionApply - large limit
- unimplemented: Builtins::Generate_ArgumentsAdaptorTrampoline - non-function call
- The files have not been lint'd yet.
Review URL: http://codereview.chromium.org/1930
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@289 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
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
