Using insertion-sort won't have too much of an overhead for the short arrays for bootstrapping (which are probably snapshot anyway).
CopyAppendCallbackDescriptors was extending and sorting the array in a loop. By using an append that inserts at the right position we do not need to resort in each iteration.
Additionally remove Sort and rename SortUnchecked to Sort. The IsSortedNoDuplicates check is moved into InitializeDescriptor.
Review URL: https://chromiumcodereview.appspot.com/10808011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12136 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
AccessorPair related transitions are now also stored as single map links, simplifying the code that handles transitions. AccessorPairs can now be shared between descriptor arrays, since they can only be mutated after another transition anyway; during which the pair is copied before writing.
Review URL: https://chromiumcodereview.appspot.com/10784014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12097 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The LastAdded points to the descriptor that was last added to the array. From the descriptor we can deduce the NextEnumerationIndex. This allows us to quickly find the property that we are transitioning to, which is necessary for transition-intensive code, eg JSON parsing.
Review URL: https://chromiumcodereview.appspot.com/10695120
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12042 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In this design maps contain descriptor arrays, which in turn can contain transition arrays. If transitions are needed when no descriptor array is present, a descriptor array without real descriptors is inserted just so it can point at the transition array.
The transition array does not contain details about the field it transitions to. In order to weed out transitions to FIELDs from CONSTANT_FUNCTION (what used to be MAP_TRANSITION vs CONSTANT_TRANSITION), the transition needs to be followed and the details need to be looked up in the target map. CALLBACKS transitions are still easy to recognize since the transition targets are stored as an AccessorPair containing the maps, rather than the maps directly.
Currently AccessorPairs containing a transition and an accessor are shared between the descriptor array and the transition array. This simplifies lookup since we only have to look in one of both arrays. This will change in subsequent revisions, when descriptor arrays will become shared between multiple maps, since transitions cannot be shared.
Review URL: https://chromiumcodereview.appspot.com/10697015
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11994 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Instead of overwriting non-live transitions with NULL_DESCRIPTORs, we remove them from the array by compacting the array (shifting live values to the left) and in-place trimming the array. If the final descriptor array contains no live values (only contained transitions which are now all cleared), we move bit_field3 back from the descriptor array to the map. The descriptor array itself will be collected in the next GC.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10575032
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11922 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Ensure that IsFound() is only used when not in combination with other
checks. To do so, the default type is NONEXISTENT rather than NORMAL;
and NotFound() also resets the type to NONEXISTENT.
- Use test methods rather than .type() == A_PROPERTY_TYPE.
Review URL: https://chromiumcodereview.appspot.com/10626004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11899 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The CompilationInfo record now saves a Zone, and the compiler pipeline
allocates memory from the Zone in the CompilationInfo. Before
compiling a function, we create a Zone on the stack and save a pointer
to that Zone to the CompilationInfo; which then gets picked up and
allocated from.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10534139
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11877 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This changes the compiler to be more aggressive about lazy compilation
of closures with non-trivial outer context. Compilation can only be
triggered with a valid outer context now. One exception is the debugger,
which can request compilation of arbitrary shared code, but it ensures
to trigger compilation only at points where no context is needed.
This relands r11782, r11783, r11790 and a minor fix.
R=ulan@chromium.org
TEST=mjsunit/debug-script-breakpoints-nested
Review URL: https://chromiumcodereview.appspot.com/10543141
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11866 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Fixed invalid memory access when reading enum-cache from descriptor array with elements transitions but 0 real descriptors.
- Fixed infinite recursion in the intrusive map iterator when visiting elements transitions.
- Properly cached non-fastmode elements transitions.
Review URL: https://chromiumcodereview.appspot.com/10565030
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11841 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This changes the compiler to be more aggressive about lazy compilation
of closures with non-trivial outer context. Compilation can only be
triggered with a valid outer context now. One exception is the debugger,
which can request compilation of arbitrary shared code, but it ensures
to trigger compilation only at points where no context is needed.
R=ulan@chromium.org
TEST=mjsunit/debug-script-breakpoints-nested
Review URL: https://chromiumcodereview.appspot.com/10538102
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11782 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This ensures that we don't accidentally throw away getters and/or setters that are still needed. To make sure the bug gets triggered, we have to construct a situation where the map is on the live side of a live->non-live transition. This ensures that the map is passed to ClearNonLiveTransitions.
BUG=v8:2163
TEST=test/mjsunit/regress/regress-2163.js
Review URL: https://chromiumcodereview.appspot.com/10535004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11713 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Removes 6 out of 8 of our remaining unintentional failures on test262.
Also fixes treatment of inherited setters added after the fact.
Specifically:
- In the runtime, when looking for setter callbacks in the prototype chain,
also look for read-only properties. If one is found, reject (exception in
strict mode). If a proxy is found, invoke proper trap.
Note: this folds in the CanPut function from the spec and avoids an extra
lookup over the prototype chain.
- In generated code for stores, insert a test for the maps from the prototype
chain, but only up to the object where the property already exists (which
may be the object itself).
In Hydrogen, if the found property is read-only or not cacheable (e.g. a
proxy), bail out; in a stub, generate an unconditional miss (to get an
exception in strict mode).
- Add test cases and adapt existing test expectations.
R=mstarzinger@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10388047
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11694 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
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=
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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
The previous code relied on the tricky global invariant that there is no map
sharing when accessor properties are involved (or in other words: that
TransformToFastProperties is dumb enough :-). Although this is not a real
problem with the current code, this assumption breaks when map sharing in fast
mode is enabled, so we defensively copy an AccessorPair.
Review URL: https://chromiumcodereview.appspot.com/9430048
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10810 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This refactors the way we (re)define elements to perform normalization
and attribute updating at a much deeper level, thereby removing some
bogus special cases in upper runtime layers.
Most element setters take an indicator flag that distinguishes between
setting and defining. Setting of an element causes attributes to remain
unchanged, writability to be checked and callbacks to be called.
Defining of an element causes attributes to be updated and callbacks to
be overridden. The same approach could be taken for properties.
R=svenpanne@chromium.org
BUG=v8:1772
TEST=test262,test262/15.2.3.6-4-333-11
Review URL: https://chromiumcodereview.appspot.com/9443014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10808 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Only JSObject enumerables with enum cache (fast case properties, no interceptors, no enumerable properties on the prototype) are supported.
HLoadKeyedGeneric with keys produced by for-in enumeration are recognized and rewritten into direct property load by index. For this enum-cache was extended to store property indices in a separate array (see handles.cc).
New hydrogen instructions:
- HForInPrepareMap: checks for-in fast case preconditions and returns map that contains enum-cache;
- HForInCacheArray: extracts enum-cache array from the map;
- HCheckMapValue: map check with HValue map instead of immediate;
- HLoadFieldByIndex: load fast property by it's index, positive indexes denote in-object properties, negative - out of object properties;
Changed hydrogen instructions:
- HLoadKeyedFastElement: added hole check suppression for loads from internal FixedArrays that are knows to have no holes inside.
R=fschneider@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9425045
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10794 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL is an intermediate step only, in the end we need to have a single
DefineOrRedefineAccessorProperty call for a single Object.defineProperty
call. Currently we can end up making two such calls, making the necessary access
checks extremely ugly and hard (impossible?) to get right for complete spec
conformance.
The bulk of the change is quite mechanical:
* Prepare an AccessorPair *before* we add it to our data structures,
eliminating the previous voodoo-like threading of a placeholder.
* The previous item makes it possible to activate our check that we do not
share AccessorPairs by accident.
* Split a monster method into 2 quite unrelated methods.
* Use templated To method in a few places.
Review URL: https://chromiumcodereview.appspot.com/9428026
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10788 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change enables optimization of top-level and eval-code. For this to work, it adds
support for declaring global variables in optimized code.
At the same time it disables the eager generation of deoptimization support data
in the full code generator (originally introduced in
r10040). This speeds up initial compilation and saves
memory for functions that won't be optimized. It requires
recompiling the function with deoptimization
support when we decide to optimize it.
Review URL: https://chromiumcodereview.appspot.com/9187005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10700 ce2b1a6d-e550-0410-aec6-3dcde31c8c00