Port r12492 (479be376)
Original commit message:
This CL adds multiple things:
Transition arrays do not directly point at their descriptor array anymore, but rather do so via an indirect pointer (a JSGlobalPropertyCell).
An ownership bit is added to maps indicating whether it owns its own descriptor array or not.
Maps owning a descriptor array can pass on ownership if a transition from that map is generated; but only if the descriptor array stays exactly the same; or if a descriptor is added.
Maps that don't have ownership get ownership back if their direct child to which ownership was passed is cleared in ClearNonLiveTransitions.
To detect which descriptors in an array are valid, each map knows its own NumberOfOwnDescriptors. Since the descriptors are sorted in order of addition, if we search and find a descriptor with index bigger than this number, it is not valid for the given map.
We currently still build up an enumeration cache (although this may disappear). The enumeration cache is always built for the entire descriptor array, even if not all descriptors are owned by the map. Once a descriptor array has an enumeration cache for a given map; this invariant will always be true, even if the descriptor array was extended. The extended array will inherit the enumeration cache from the smaller descriptor array. If a map with more descriptors needs an enumeration cache, it's EnumLength will still be set to invalid, so it will have to recompute the enumeration cache. This new cache will also be valid for smaller maps since they have their own enumlength; and use this to loop over the cache. If the EnumLength is still invalid, but there is already a cache present that is big enough; we just initialize the EnumLength field for the map.
When we apply ClearNonLiveTransitions and descriptor ownership is passed back to a parent map, the descriptor array is trimmed in-place and resorted. At the same time, the enumeration cache is trimmed in-place.
Only transition arrays contain descriptor arrays. If we transition to a map and pass ownership of the descriptor array along, the child map will not store the descriptor array it owns. Rather its parent will keep the pointer. So for every leaf-map, we find the descriptor array by following the back pointer, reading out the transition array, and fetching the descriptor array from the JSGlobalPropertyCell. If a map has a transition array, we fetch it from there. If a map has undefined as its back-pointer and has no transition array; it is considered to have an empty descriptor array.
When we modify properties, we cannot share the descriptor array. To accommodate this, the child map will get its own transition array; even if there are not necessarily any transitions leaving from the child map. This is necessary since it's the only way to store its own descriptor array.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10918287
Patch from Akos Palfi <palfia@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12549 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL adds multiple things:
Transition arrays do not directly point at their descriptor array anymore, but rather do so via an indirect pointer (a JSGlobalPropertyCell).
An ownership bit is added to maps indicating whether it owns its own descriptor array or not.
Maps owning a descriptor array can pass on ownership if a transition from that map is generated; but only if the descriptor array stays exactly the same; or if a descriptor is added.
Maps that don't have ownership get ownership back if their direct child to which ownership was passed is cleared in ClearNonLiveTransitions.
To detect which descriptors in an array are valid, each map knows its own NumberOfOwnDescriptors. Since the descriptors are sorted in order of addition, if we search and find a descriptor with index bigger than this number, it is not valid for the given map.
We currently still build up an enumeration cache (although this may disappear). The enumeration cache is always built for the entire descriptor array, even if not all descriptors are owned by the map. Once a descriptor array has an enumeration cache for a given map; this invariant will always be true, even if the descriptor array was extended. The extended array will inherit the enumeration cache from the smaller descriptor array. If a map with more descriptors needs an enumeration cache, it's EnumLength will still be set to invalid, so it will have to recompute the enumeration cache. This new cache will also be valid for smaller maps since they have their own enumlength; and use this to loop over the cache. If the EnumLength is still invalid, but there is already a cache present that is big enough; we just initialize the EnumLength field for the map.
When we apply ClearNonLiveTransitions and descriptor ownership is passed back to a parent map, the descriptor array is trimmed in-place and resorted. At the same time, the enumeration cache is trimmed in-place.
Only transition arrays contain descriptor arrays. If we transition to a map and pass ownership of the descriptor array along, the child map will not store the descriptor array it owns. Rather its parent will keep the pointer. So for every leaf-map, we find the descriptor array by following the back pointer, reading out the transition array, and fetching the descriptor array from the JSGlobalPropertyCell. If a map has a transition array, we fetch it from there. If a map has undefined as its back-pointer and has no transition array; it is considered to have an empty descriptor array.
When we modify properties, we cannot share the descriptor array. To accommodate this, the child map will get its own transition array; even if there are not necessarily any transitions leaving from the child map. This is necessary since it's the only way to store its own descriptor array.
Review URL: https://chromiumcodereview.appspot.com/10909007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12492 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This fixes materialization of arguments objects for strict mode functions during
deoptimization. We materialize arguments from the stack area where optimized
code pushes the arguments when entering the inlined environment. For adapted
invocations we use the arguments adaptor frame for materialization.
R=svenpanne@chromium.org
BUG=v8:2261
TEST=mjsunit/regress/regress-2261,mjsunit/compiler/inline-arguments
Review URL: https://chromiumcodereview.appspot.com/10908194
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12489 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
xmm0 is not saved across runtime call on x64 because MacroAssembler::EnterExitFrameEpilogue preserves only allocatable XMM registers unlike on ia32 where it preserves all registers.
Cleanup handling of shifts: SHR can deoptimize only when its a shift by 0, all other shift never deoptimize.
Fix type inference for i-to-t change instruction. On X64 this ensures that write-barrier is generated correctly.
R=danno@chromium.org
Review URL: https://chromiumcodereview.appspot.com/10868032
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12373 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Safe operations are those that either do not observe unsignedness or have special support for uint32 values:
- all binary bitwise operations: they perform ToInt32 on inputs;
- >> and << shifts: they perform ToInt32 on left hand side and ToUint32 on right hand side;
- >>> shift: it performs ToUint32 on both inputs;
- stores to integer external arrays (not pixel, float or double ones): these stores are "bitwise";
- HChange: special support added for conversions of uint32 values to double and tagged values;
- HSimulate: special support added for deoptimization with uint32 values in registers and stack slots;
- HPhi: phis that have only safe uses and only uint32 operands are uint32 themselves.
BUG=v8:2097
TEST=test/mjsunit/compiler/uint32.js
Review URL: https://chromiumcodereview.appspot.com/10778029
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12367 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Highlights of this CL:
* Introduced a new opcode in the deoptimizer for a setter stub frame.
* Added a global setter stub for returning after deoptimizing a setter.
* We do not need special deopt support for getters, although the getter stub creates an internal frame. The normal machinery works just right for this case, although we generate a stack that can never occur during normal fullcode execution. If this hurts us one day, we can parameterize and reuse the setter deopt machinery.
Review URL: https://chromiumcodereview.appspot.com/10855098
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12328 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in anticipation of the upcoming lexical global scope.
Mostly automatised as:
for FILE in `egrep -ril "global[ _]?context" src test/cctest`
do
echo $FILE
sed "s/Global context/Native context/g" <$FILE >$FILE.0
sed "s/global context/native context/g" <$FILE.0 >$FILE.1
sed "s/global_context/native_context/g" <$FILE.1 >$FILE.2
sed "s/GLOBAL_CONTEXT/NATIVE_CONTEXT/g" <$FILE.2 >$FILE.3
sed "s/GlobalContext/NativeContext/g" <$FILE.3 >$FILE
rm $FILE.[0-9]
done
R=mstarzinger@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10832342
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12325 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This fixes the positive lookup performed by these LoadICs, to use the
holder instead of the receiver to perfrom the lookup on. It also extends
this improvement to KeyedLoadICs. And it fixes a bug introduced for the
JavaScript getter case of a LoadIC.
R=erik.corry@gmail.com
BUG=chromium:142088
TEST=cctest/test-api/Regress142088,cctest/test-api/Regress137002b
Review URL: https://chromiumcodereview.appspot.com/10828303
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12311 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Now a map points to a transition array which contains the descriptor array. The descriptor array is now immutable. The next step is to share the descriptor array with all back-pointed maps as long as there is a single line of extension. Maps that require a descriptor array but don't need transitions will still need a pseudo-empty transition array to contain the descriptor array.
Review URL: https://chromiumcodereview.appspot.com/10816005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12298 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
regardless of the detected CPU. This is a requirement for the
debugger and the deoptimizer, which both expect that code from
the snapshot (compiled without VFP and ARM7) should have the
same layout as code compiled later.
This is another change to make snapshots more robust with
arbitrary code.
Review URL: https://chromiumcodereview.appspot.com/10824235
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12287 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Currently only simple setter calls are handled (i.e. no calls in count
operations or compound assignments), and deoptimization in the setter is not
handled at all. Because of the latter, we temporarily hide this feature behind
the --inline-accessors flag, just like inlining getters.
We now use an enum everywhere we depend on the handling of a return value,
passing around several boolean would be more confusing.
Made VisitReturnStatement and the final parts of TryInline more similar, so
matching them visually is a bit easier now.
Simplified the signature of AddLeaveInlined, the target of the HGoto can simply
be retrieved from the function state.
Review URL: https://chromiumcodereview.appspot.com/10836133
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12286 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
mksnapshot or a VM that is booted from a snapshot. --debug-code
can still have an effect on stub and optimized code and it still
works on the full code generator when running without snapshots.
The deoptimizer generates full-code-generator code and relies on it having
the same layout as last time. This means that the code the full code
generator makes for the snapshot should be the same as the code it makes
later. This change makes the full code generator create more consistent
code between mksnapshot time and run time.
This is a bug fix and a step towards making the snapshot code more robust.
Review URL: https://chromiumcodereview.appspot.com/10834085
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12239 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The deoptimizer generates full-code-generator code and relies on it having
the same layout as last time. This means that the code the full code
generator makes for the snapshot should be the same as the code it makes
later. This change makes the full code generator create more consistent
code between mksnapshot time and run time.
This is a bug fix and a step towards making the snapshot code more robust.
Review URL: https://chromiumcodereview.appspot.com/10824084
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12233 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Currently only simple getter calls are handled (i.e. no calls in count
operations or compound assignments), and deoptimization in the getter is not
handled at all. Because of the latter, we temporarily hide this feature behind a
new flag --inline-accessors, which is false by default.
Review URL: https://chromiumcodereview.appspot.com/10828066
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12223 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
- 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
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
When an array index (in an array access) is a simple "expression + constant", just embed the constant in the array access operation so that the full index expression is (potentially) no longer used and its live range can be much shorter.
This is effective in conjunction with array bounds check removal (otherwise the index is anyway used in the check).
Review URL: https://chromiumcodereview.appspot.com/10382055
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11596 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Until now we always recorded two deoptimization environments for instructions
that are marked as calls. We actually don't need two for all LIR
instructions except one (LInstanceOfKnownGlobal) where there is a lazy
deoptimization point in deferred code.
This change remove on of them and uses one virtual function instead
to make LInstanceOfKnownGlobal work as before.
Additionally, this change removes an unused predicate save_doubles_ from LIR
instructions and removes some helper functions that are used only in one place.
Review URL: https://chromiumcodereview.appspot.com/10035021
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11454 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
Do proper dispatch on declaration type instead of mingling together
different code generation paths. Once we add more declaration forms,
this is more scalable.
In separate steps, I'd like to (1) clean up the logic for DeclareGlobal,
and (2) try to reduce the special handling of the name function var if
possible.
R=fschneider@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9704054
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11331 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Some GWT compiled code results in array access that has a heap number (e.g. -0)
as an index. Until now this would result in a generic IC.
For example:
a[-0] === a[0] or
a[0.25 * 4] === a[1]
This change detects heap numbers that are representable as a smi
and converts them. As a result we can still use the fast keyed monomorphic
ICs. Optimized code already handles keyed access with a double-key efficiently.
As a result the frame rate on the reported benchmark improves by roughly 2x.
BUG=v8:1388,v8:1295
Review URL: https://chromiumcodereview.appspot.com/9837109
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11282 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
regexp can match by using a Boyer-Moore-like table. This is done by identifying
non-greedy non-capturing loops in the nodes that eat any character one at a time.
For example in the middle of the regexp /foo[\s\S]*?bar/ we find such a loop.
There is also such a loop implicitly inserted at the start of any non-anchored
regexp.
When we have found such a loop we look ahead in the nodes to find the set of
characters that can come at given distances. For example for the regexp
/.?foo/ we know that there are at least 3 characters ahead of us, and the sets
of characters that can occur are [any, [f, o], [o]]. We find a range in the
lookahead info where the set of characters is reasonably constrained. In our
example this is from index 1 to 2 (0 is not constrained). We can now look 3
characters ahead and if we don't find one of [f, o] (the union of [f, o] and
[o]) then we can skip forwards by the range size (in this case 2).
For Unicode input strings we do the same, but modulo 128.
We also look at the first string fed to the regexp and use that to get a hint
of the character frequencies in the inputs. This affects the assessment of
whether the set of characters is 'reasonably constrained'.
We still have the old lookahead mechanism, which uses a wide load of multiple
characters followed by a mask and compare to determine whether a match is
possible at this point.
Review URL: http://codereview.chromium.org/9965010
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11204 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Lithium translation rebuilds hydrogen environments from scratch so we have to ensure that arguments object is correctly bound on function entry otherwise deoptimization will not materialize it.
This fix was implemented as part of r11109 and then reverted.
R=danno@chromium.org
BUG=v8:2045
TEST=test/mjsunit/regress/regress-2045.js
Review URL: https://chromiumcodereview.appspot.com/9963008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11194 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
