Commit Graph

1788 Commits

Author SHA1 Message Date
rossberg@chromium.org
ce05280bfc Get rid of static module allocation, do it in code.
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
2012-11-22 10:25:22 +00:00
rossberg@chromium.org
4751776dce Object.observe: Unblacklist some tests involving indexed properties
These were erroneously disabled because they were expecting indexed properties to be of Number type when appearing as the "name" in change records. But the "name" property will always be a string. Fixed assertRecordsEqual() to enforce this in expectations.

BUG=v8:2409

Review URL: https://codereview.chromium.org/11280105
Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13027 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-21 12:50:49 +00:00
mmassi@chromium.org
5e7f30a596 Use the property load IC for accessing the array length.
BUG=

Review URL: https://chromiumcodereview.appspot.com/11299004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13025 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-21 11:49:15 +00:00
yangguo@chromium.org
89bc2eb93f Actually relax test expectations for known failing test.
This corrects r13011.

R=mstarzinger@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/11415093

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13020 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-21 09:32:06 +00:00
jkummerow@chromium.org
a956594fc2 Fix corner case in x64 compare stubs.
BUG=v8:2416

Review URL: https://codereview.chromium.org/11413087

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13019 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-20 15:57:10 +00:00
rossberg@chromium.org
6add3222ed Object.observe: Add test case covering most special cases.
Things not working yet are currently blacklisted in the test (see TODOs).

R=verwaest@chromium.org
BUG=

Review URL: https://codereview.chromium.org/11377157

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13016 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-20 14:45:21 +00:00
yangguo@chromium.org
bfbca55d02 Relax test expectations for known failing test.
BUG=

Review URL: https://chromiumcodereview.appspot.com/11299100

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13011 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-20 12:31:41 +00:00
rossberg@chromium.org
1570d62721 Object.observe/unobserve now return object
BUG=v8:2418

Review URL: https://codereview.chromium.org/11419078
Patch from Rafael Weinstein <rafaelw@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13009 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-20 10:38:14 +00:00
verwaest@chromium.org
08cfda49f2 Ensure CopyElementsImpl is always executed so it fills in holes even if from_size is 0. Allow FixedDoubleArray::cast to also support FixedArray with size 0.
Review URL: https://chromiumcodereview.appspot.com/11280054

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13000 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-19 15:00:34 +00:00
yangguo@chromium.org
d2a6e7b40d Fix test failures.
R=jkummerow@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/11414030

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12992 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-16 14:24:19 +00:00
rossberg@chromium.org
8d79ff46d0 Clean-up refactoring to eliminate GetLocalElementKind.
Eliminates substantial amounts of fragile code duplication and special casing.

Also fixes "a".propertyIsEnumerable(0) to correctly return true.

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/11420011

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12990 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-16 13:28:34 +00:00
mstarzinger@chromium.org
3d1582c474 Fix Array.prototype.join evaluation order.
R=yangguo@chromium.org
BUG=v8:2263
TEST=mjsunit/regress/regress-2263

Review URL: https://codereview.chromium.org/11280025

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12989 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-16 12:45:23 +00:00
yangguo@chromium.org
af6f7742e0 Fix test failures.
R=jkummerow@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/11299033

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12988 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-16 11:58:21 +00:00
yangguo@chromium.org
63f109aaa5 Introduce helper functions to test parallel recompilation.
BUG=

Review URL: https://chromiumcodereview.appspot.com/11419012

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12986 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-16 10:57:50 +00:00
rossberg@chromium.org
2e76922c79 Object.observe: Use [[DefineOwnProperty]] to create properties of changeRecord.
Note: The test here requires https://codereview.chromium.org/11364237/ to land in order to pass because Object.freeze calls Object.getOwnPropertyNames().

BUG=v8:2411

Review URL: https://codereview.chromium.org/11377171
Patch from Rafael Weinstein <rafaelw@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12983 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-16 09:35:27 +00:00
rossberg@chromium.org
af824eab8f When using an Object as a set in Object.getOwnPropertyNames, null out the proto
Also apply the same fix elsewhere in v8natives.js

BUG=v8:2410

Review URL: https://codereview.chromium.org/11364237
Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12982 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-16 09:32:39 +00:00
verwaest@chromium.org
a08194c83a Support all fast elements kinds in the major array operations.
Currently missing support for unshift.

BUG=

Review URL: https://chromiumcodereview.appspot.com/11377132

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12969 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-15 12:19:14 +00:00
rossberg@chromium.org
4fb992a872 Object.observe: Handle oldValue for elements with accessors properly.
Extended ElementAccessor interface to allow querying PropertyType and
AccessorPair. Also added respective functionality to JSObject.

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/11358234

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12967 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-15 11:31:40 +00:00
rossberg@chromium.org
5e7b796479 Object.observe: Move notification of JSArray length changes to JSArray::SetElementsLength
The previous implementation in Accessors::ArraySetLength failed when array length was set through StoreIC_ArrayLength. But that stub and the accessor both delegate to JSArray::SetElementsLength, so moving the code there allows notifications to be sent in both cases.

Review URL: https://codereview.chromium.org/11275292
Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12962 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-14 16:51:21 +00:00
jkummerow@chromium.org
1c086d1202 Lattice-based representation inference, powered by left/right specific type feedback for BinaryOps and comparisons
Review URL: https://chromiumcodereview.appspot.com/10837165

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12961 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-14 15:59:45 +00:00
ulan@chromium.org
74492ab2d4 Emit VMLA for multiply-add on ARM
Review URL: https://chromiumcodereview.appspot.com/11293061
Patch from Hans Wennborg <hans@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12958 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-14 11:01:18 +00:00
yangguo@chromium.org
4783d3c31b Remove 'type' and 'arguments' properties from Error object.
R=svenpanne@chromium.org
BUG=v8:2397

Review URL: https://chromiumcodereview.appspot.com/11358214

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12956 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-14 09:14:47 +00:00
peter.rybin@gmail.com
bb53dc6890 Issue 2368: LiveEdit crashes when new object/array literal is added
Review URL: https://codereview.chromium.org/11191039

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12952 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-13 19:13:27 +00:00
rossberg@chromium.org
36c3d01589 Object.unobserve(obj, callback) now throws a TypeError when callback is not a function.
Review URL: https://codereview.chromium.org/11293248
Patch from Rafael Weinstein <rafaelw@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12950 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-13 15:50:59 +00:00
yangguo@chromium.org
693ee09cf3 Correctly check for stack overflow even when interrupt is pending.
BUG=v8:214

Review URL: https://chromiumcodereview.appspot.com/11362007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12936 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-12 14:56:25 +00:00
yangguo@chromium.org
4c27298d27 Collect stack trace on stack overflow.
BUG=v8:2394

Review URL: https://chromiumcodereview.appspot.com/11275186

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12933 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-12 14:54:29 +00:00
yangguo@chromium.org
e3e899fe53 Correctly fix test expectations.
R=jkummerow@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/11369183

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12931 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-12 14:07:21 +00:00
yangguo@chromium.org
eea60ff76a Fix test expectations.
R=jkummerow@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/11361217

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12928 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-12 12:29:15 +00:00
yangguo@chromium.org
4cca6c6081 Make formatting error message side-effect-free.
BUG=v8:2398

Review URL: https://chromiumcodereview.appspot.com/11359130

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12926 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-12 10:33:20 +00:00
yangguo@chromium.org
ef1b3d3a76 Fix length check in JSON.stringify.
R=verwaest@chromium.org
BUG=160010

Review URL: https://chromiumcodereview.appspot.com/11410031

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12925 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-12 10:20:07 +00:00
rossberg@chromium.org
0e7306cc92 Implement Object.getNotifier() and remove Object.notify()
Updated all tests to use getNotifier or actual object mutation instead of notify, and added tests for new behavior of getNotifier.

Review URL: https://codereview.chromium.org/11369154
Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12923 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-09 16:14:42 +00:00
rossberg@chromium.org
af7bfe0e27 Minimal implementation and tests of observable array methods
Bail out of any special-casing in array methods.
Further optimization is possible, but can be left for later.

Review URL: https://codereview.chromium.org/11369151
Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12917 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-09 12:28:22 +00:00
rossberg@chromium.org
13f8fb47da Add more test coverage for setting Array.length
Covers truncation of holey arrays and defineProperty('length').

Review URL: https://codereview.chromium.org/11369150
Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12915 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-09 11:00:13 +00:00
rossberg@chromium.org
b72e5811e7 Object.observe: notify when element addition causes array growth
Review URL: https://codereview.chromium.org/11369135
Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12914 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-09 10:57:54 +00:00
mstarzinger@chromium.org
2d69a2b12e ES6: Add support for Set and Map clear method
http://wiki.ecmascript.org/doku.php?id=harmony:specification_drafts, section
15.14.5.3 and 15.14.5.2

BUG=v8:2400

Review URL: https://codereview.chromium.org/11409002
Patch from Erik Arvidsson <arv@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12909 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-09 09:01:29 +00:00
yangguo@chromium.org
64da47559c Turn message property of the error object into a data property.
R=svenpanne@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/11368142

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12908 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-09 08:22:02 +00:00
rossberg@chromium.org
2af4744889 Handle Object.observe notifications for setting Array.length
Also handles notification of deleted properties when an array
is truncated by setting length.

Review URL: https://codereview.chromium.org/11338048
Patch from Adam Klein <adamk@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12905 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-08 16:12:12 +00:00
rossberg@chromium.org
8eb704257f Object.observe: Fixed missing case for turning off ICs.
R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/11358122

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12901 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-08 13:15:54 +00:00
rossberg@chromium.org
fbc6e0d883 Object.observe: generate change records for indexed properties.
Details:
- Extend ElementAccessors with GetAttributes method.
- Add HasLocalElement, Get[Local]ElementAttribute methods to JSReceiver/JSObject.
- Otherwise, mirror implementation for named properties.

Cannot correctly handle the cases yet where an accessor is redefined or deleted.

Also fixed handling of object info table.

(Based on CL https://codereview.chromium.org/11362115/)

R=verwaest@chromium.org,mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/11365111

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12900 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-08 12:58:08 +00:00
mstarzinger@chromium.org
a31889e2de Fix slack tracking when instance prototype changes.
This fixes a corner case when the instance prototype of a function is
changed while inobject slack tracking is still in progress. This caused
the intial map to be unrelated for functions with the same shared info
and hence the shared construct stub is no longer generic enough to work
for all those functions.

R=danno@chromium.org
BUG=chromium:157019
TEST=mjsunit/regress/regress-crbug-157019

Review URL: https://codereview.chromium.org/11293059

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12896 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-08 11:56:44 +00:00
rossberg@chromium.org
e059e64c98 Object.observe: include oldValue in change records,
plus more accurate distinction of different change types.

Required handlifying more code.

Also fixed a handlification bug in JSProxy::GetElementAttributeWithHandler.

R=verwaest@chromium.org
BUG=

Review URL: https://codereview.chromium.org/11362115

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12888 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-07 14:14:50 +00:00
yangguo@chromium.org
ecb6126e45 Remove check for recursion depth for JSON.stringify.
R=mstarzinger@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/11368119

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12882 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-07 12:12:52 +00:00
mstarzinger@chromium.org
e405ff84b4 ES6: Adding support for size to Set and Map
Section 15.14.5.10 and 15.16.5.7 in the October 26, 2012 ES6 draft,
http://wiki.ecmascript.org/doku.php?id=harmony:specification_drafts

This adds a getter for "size" to Set.prototype and Map.prototype which reflects
the number of elements in the Set and Map respectively.

BUG=v8:2395

Review URL: https://codereview.chromium.org/11360089
Patch from Erik Arvidsson <arv@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12875 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-06 18:14:45 +00:00
rossberg@chromium.org
b80cbd7922 Object.observe: generate change records for named properties.
In more detail:
- Set observation bit for observed objects (and make NormalizedMapCache respect it).
- Mutation of observed objects is always delegated from ICs to runtime.
- Introduce JS runtime function for notifying generated changes.
- Invoke this function in the appropriate places (including some local refactoring).
- Inclusion of oldValue field is not yet implemented, nor element properties.

Also, shortened flag to --harmony-observation.

R=verwaest@chromium.org
BUG=

Review URL: https://codereview.chromium.org/11347037

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12867 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-06 12:32:36 +00:00
ulan@chromium.org
f106c9c9f7 Add rotate-right instruction to hydrogen and use it instead of bitwise operations
of the form ((x >>> i) | (x << (32 - i))).

This CL is based on https://chromiumcodereview.appspot.com/10984057/
by Jay Conrod <dconrod@codeaurora.org>.

R=danno@chromium.org,mstarzinger@chromium.org,dconrod@codeaurora.org

Review URL: https://chromiumcodereview.appspot.com/11033005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12855 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-05 13:28:10 +00:00
yangguo@chromium.org
e452c10702 Add fast path for FastProperty objects in JSON.stringify.
R=verwaest@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/11363078

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12853 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-05 12:59:35 +00:00
yangguo@chromium.org
e26012e771 Fix JSON.stringify wrt harmony proxies.
BUG=

Review URL: https://chromiumcodereview.appspot.com/11312063

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12851 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-05 10:53:56 +00:00
svenpanne@chromium.org
9de1d40d28 Improve handling of property loads on the proto chain.
Previously Crankshaft emitted a generic load for these, now we emit a load of a
named field, guarded by a proto chain check.

LCheckPrototypeMaps now returns the holder, which is for free, because it
already had to check its map as the last step, anyway. This is in sync with what
StubCompiler::CheckPrototype does.

Review URL: https://codereview.chromium.org/11338030

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12847 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-05 08:53:54 +00:00
yangguo@chromium.org
e8d91b424c Handle edge cases in basic JSON.stringify.
BUG=

Review URL: https://chromiumcodereview.appspot.com/11315009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12842 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-02 14:46:57 +00:00
verwaest@chromium.org
14abf05bd5 Ensure reducing the length of an array doesn't make it go holey.
Also only transition and/or change anything to the backing store if we are
actually going to delete anything.

BUG=

Review URL: https://chromiumcodereview.appspot.com/11358011

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12840 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2012-11-02 10:24:56 +00:00