If a two-byte string only contains ascii characters, then we can save
memory when flattening a cons string containing it. Similarly we can
use this in Array.prototype.join implementation. To track this a new
bit is added to instance type. This bit is used as a hint in generated
code and in runtime functions.
To enable testing a new V8 extension is added controlled by
--expose-externalize-string flag.
Review URL: http://codereview.chromium.org/2762008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4894 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
With the change in r4820 all return statements are now breakable like any statement, so stepping will stop before the return statement actually returning from a function. With this change the position when breaking in the function return (after executing the return statement) will be the actual end of the function. At this point the return value is available as it saved to the stack by the debug break at return handling. Added information on the actual value returned from the function to the debugger.
Review URL: http://codereview.chromium.org/2783002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4835 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Added support for more precise break points when debugging and stepping. To achieve that additional nop instructions are inserted where breaking would otherwise be impossible. The number of nop instructions inserted are sufficient to make place for patching with a call to a debug break code stub. On Intel that is 5 nop's for 32-bit and 13 for 64-bit. Om ARM 3 nop instructions (12 bytes) are required.
In order to avoid inserting nop's in to many places a simple ast checker have been added to check whether there are breakable code in a statement or expression. If it is possible to break in an expression no additional break enabeling code is inserted.
Added break locations to the true and false part of a conditional expression.
Added stepping tests to cover more constructs.
These changes are only in the full compiler.
Changed the default value for the option --debugger in teh d8 shell from true to false. The reason for this is that with --debugger turned on the full compiler will be used for all code in when running d8, which can be unexpeceted.
Review URL: http://codereview.chromium.org/2693002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4820 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In mjsunit/const-eval-init - testInitSlowCaseExtension a range of objects are initialized to undefined instead of a value because the variable i is within quotes (i.e., the source becommes "a1 = i" instead of "a1 = 1".
This should have no impact on the test, I just stumbled over this on
an unrelated matter.
Review URL: http://codereview.chromium.org/2758002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4817 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
perform a context lookup in the runtime system for the 'eval'
function. Instead load the 'eval' function from the global context in
generated code if it is not shadowed.
Will port to other platforms as a separate change.
Review URL: http://codereview.chromium.org/2666001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4794 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This fix adds support for retriving a property descriptor on elements. The
new version supports both fast and slow case elements. In the fast case
we always default configurable, writable, enumerable to true (we don't have
PropertyDetails for fast elements).
A few new tests are added to get-own-property-descriptor.js, I will
add a lot more to object-define-property when I add support for indices in
Object.defineProperty.
Review URL: http://codereview.chromium.org/2278002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4738 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
NumberToUint32 that I was trying to use maps -0 to +0 (as desired) but
also maps +/-Infinity to +0, which made +/-Infinity a valid string
index. I fixed it by introducing a new runtime function with the right
semantics.
TEST=LayoutTests/fast/js/char-at.html,mjsunit/string-charat.js
Review URL: http://codereview.chromium.org/2223003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4734 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
These string methods can be composed from two basic blocks: charCodeAt
and fromCharCode, both of which have fast cases for certain types of
inputs. In this patch these two blocks are refactored to allow
generating the fast cases without having to jump around the slow
cases. In the slow cases since they can now be invoked both from
inline runtime functions and from IC stubs we either have to
save/restore state of the current frame or enter/leave a new internal
frame. This is handled by new RuntimeCallHelper interface. Its
implementation for virtual frame is based on FrameRegisterState class
extracted from DeferredCode class.
Review URL: http://codereview.chromium.org/2087009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4733 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The existing version will overwrite the existing writable flag with
false even in the case where no new value is given and the existing
writable flag is true.
The reason for the issue is that there is no check to see if the
provided descriptor actually has a writable attribute. This causes us
to use the default value (false) even in the case where nothing was
provided. In addition, the existing tests makes wrong assumptions (that writable is always set to false if not provided) and has been changed to follow the specification.
Review URL: http://codereview.chromium.org/2271001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4720 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Noticing that the only difference between samevalue and strict equality is on
numbers we can simplify SameValue.
The old version did not return a correct answer if called on two strings since
StringEquals (from runtime.cc) returns an answer that is the negated value
(if treated as a boolean).
Review URL: http://codereview.chromium.org/2136024
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4713 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Object.defineProperty with empty property descriptor.
The issue is fixed by implementing step 5 and 6 from DefineOwnProperty in the
specification (ES5 8.12.9).
This also fixes a bug in SameValue when used on boolean values (it
would priorly return a number - not a boolean).
Review URL: http://codereview.chromium.org/2131019
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4708 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change allows Object.create to take a function as input in the
proto argument. The spec says that Type(O) for the proto argument
should be true but our IS_OBJECT does not check for this. I will make a
IS_SPEC_OBJECT in macros.py and refactor v8natives in another CL.
Review URL: http://codereview.chromium.org/2051001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4622 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The error was introduced in revision 4557 where support was added for
ES5 date time format strings. Because there was no check for a valid
year a random string starting with a non-digit character would be
parsed.
This change disallows ES5 formatted dates where there is no date
fraction (i.e., with only a timestamp). Since none of the other
browsers support Date.parse on only timestamps I have disabled this
totally instead of just correcting the parser.
Review URL: http://codereview.chromium.org/2017005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4613 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
