This is basically r11496, with the following changes:
* Set back pointers in maps (cherry-picked from r11528)
* Fixed size calculation in CopyInsert, as proposed by mstarzinger/rossberg
* DefineFastAccessor uses GetCallbackObject instead of GetValue (for __proto__)
* Put the code under a new flag, which is disabled by default
* Cut down the corresponding regression test
* Adapted bootup memory test, we actually only need a bit more memory on 64bit without snapshots, which can easily explained by more live maps lying around. Note that the snapshot variants are back to their previous limits.
Next steps: Investigate any performance degradationswith the flag enabled, and finally remove the flag when things are OK. Furthermore, GetCallbackObject should be merged into GetValue, the distinction is confusing and error-prone.
Review URL: https://chromiumcodereview.appspot.com/10445009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11651 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This makes back pointers in the map transition tree explicit by having
accurate back pointers throughout the lifetime of maps instead of
establishing and destroying back pointers before and after each marking
phase. This is a prerequisite for being able to clear map transitions
during incremental marking.
R=vegorov@chromium.org
BUG=v8:1465
Review URL: https://chromiumcodereview.appspot.com/10381053
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11528 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
AccessorPairs can now contain map transitions, which is similar to our current
handling of CONSTANT_FUNCTION/CONSTANT_TRANSITION, but generalized to a pair for
holding info about the getter and the setter. This way we can achieve map
sharing for objects with accessor properties, which is a prerequisite for making
them fast via inlining. We fall back to the previous way of handling accessor
properties when sharing is not possible or we don't handle a special case.
Note: When an exisiting accessor property is redefined we could in principle
move the AccessorPair out of the descriptor into the object itself (again just
like the way we do something similar for CONSTANT_FUNCTION/CONSTANT_TRANSITION),
but this would require a new property kind for holding a pair of values. Perhaps
we can implement this later, but for now this hopefully rare case is handled
like before, losing map sharing and potentially creating more maps than strictly
necessary.
Review URL: https://chromiumcodereview.appspot.com/10238005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11496 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Constructs the (generally cyclic) graph of module instance objects
and populates their exports. Any exports other than nested modules
are currently set to 'undefined' (but already present as properties).
Details:
- Added new type JSModule for instance objects: a JSObject carrying a context.
- Statically allocate instance objects for all module literals (in parser 8-}).
- Extend interfaces to record and unify concrete instance objects,
and to support iteration over members.
- Introduce new runtime function for pushing module contexts.
- Generate code for allocating, initializing, and setting module contexts,
and for populating instance objects from module literals.
Currently, all non-module exports are still initialized with 'undefined'.
- Module aliases are resolved statically, so no special code is required.
- Make sure that code containing module constructs is never optimized
(macrofy AST node construction flag setting while we're at it).
- Add test case checking linkage.
Baseline: http://codereview.chromium.org/9722043/R=svenpanne@chromium.org,mstarzinger@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9844002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11336 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
I also discovered that our treatment of const declarations is inconsistent
when inside a global eval under 'with' (i.e., when created by
DeclareContextSlots). That is,
var x;
eval("const x = 9")
and
var x;
eval("with({}) const x = 9")
differ (the former assigns 9, the latter throws). This appears to be an
oversight from earlier changes to our const semantics (the latter shouldn't
throw either). Fixing this is a separate issue, though (and one that doesn't
seem quite worthwhile).
R=mstarzinger@chromium.org
BUG=v8:1991,80591
TEST=
Review URL: https://chromiumcodereview.appspot.com/10067010
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11333 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Although things are currently OK here, in the future it won't be enough to check
for the existence of a CALLBACKS result, we must additionally check that it
actually contains an accessor. In a nutshell: 'sed s/IsFound/IsProperty/' once
again...
Additionally, the control flow in DefinePropertyAccessor has been simplified by
using a helper function.
Review URL: https://chromiumcodereview.appspot.com/10071009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11305 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Now the whole getter/setter/attributes triple gets created/set together,
avoiding any hacks regarding previous values/attributes, making things a lot
simpler.
While doing this, an interesting problem surfaced, which has been there for a
long time: After adding/changing acessors in slow mode, we could potentially
fail going back to fast mode because of a failed memory allocation, signaling
the need for a GC. But we have already changed the object in slow mode, so we
are not idempotent and the retry would trigger a newly inserted assertion
(namely, that the code obeys access restrictions). This has been solved by
splitting the transformation to fast mode from the actual setting of the
accessors.
Review URL: https://chromiumcodereview.appspot.com/9716035
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11112 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Main change from the original CL: Call::ComputeTarget does not use IsProperty
anymore, because this would potentially need a holder, which we don't have
here. Using Map::LookupInDescriptors with a NULL holder is a bit fishy in
general, because one has to be *extremely* careful when using its LookupResult.
The original CL made Chrome's NetInternalsTest.netInternalsTourTabs browser test
fail, but it's a mystery how this could happen: We should never reach
Call::ComputeTarget via Call::RecordTypeFeedback with a CALLBACKS property,
because we never consider calls to them monomorphic, which is in turn because of
the stub cache leaving them in the pre-monomorphic state. Therefore, I don't
have a clue how to write a regression test for this...
As an additional tiny bonus, the --trace-opt output for deoptimizations has been
improved.
Review URL: https://chromiumcodereview.appspot.com/9584003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10906 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This allows elements of the non-strict arguments object to be redefined
with custom attributes and still maintain an alias into the context.
Such a slow alias is maintained by placing a special marker into the
dictionary backing store of the arguments object.
R=rossberg@chromium.org
BUG=v8:1772
TEST=test262,mjsunit/object-define-property
Review URL: https://chromiumcodereview.appspot.com/9460004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10827 ce2b1a6d-e550-0410-aec6-3dcde31c8c00