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
Port r11817 (616dfcf0)
Original commit message:
Each SharedFunctionInfo gets an optimized code map to store
one optimized code object per context. When allocating a new
closure we consult this map and check if there is optimized code
that can be shared.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10557002
Patch from Akos Palfi <palfia@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11848 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11694 (29aa05e9)
Original commit message:
Implement correct checking for inherited readonliness on assignment.
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.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10539004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11717 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11596 (0cee9fca)
Original commit message:
Array index computation dehoisting.
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).
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10442003
Patch from Akos Palfi <palfia@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11644 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11492 (d14ada19)
Original commit message:
Fix register clobbering in LoadIC for interceptors.
This fixes a corner-case where the receiver register was clobbered by
LoadICs for interceptors and inlined followup code still relied on the
receiver to be intact in case of prototype changes.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10315016
Patch from Akos Palfi <palfia@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11506 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11491 (705d40cc)
Original commit message:
Implement clearing of CompareICs.
This allows CompareICs to be cleared during garbage collection to avoid
cross-context garbage retention through maps stored in CompareIC stubs
for the KNOWN_OBJECTS state.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10342024
Patch from Akos Palfi <palfia@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11505 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11454 (72c662fc)
Original commit message:
Reduce size of LIR instruction by one word and remove dead code.
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.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10233019
Patch from Akos Palfi <palfia@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11501 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11470 (621f96c0)
Original commit message:
Fix LFastLiteral to check boilerplate elements kind.
Adds a missing check that the elements kind of the boilerplate object
still has the expected elements kind, unoptimized code can transition
the boilerplate. Corner cases might cause the optimized code to be
reentered again.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10271018
Patch from Akos Palfi <palfia@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11474 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
Port r11336 (6dd4e844)
Original commit message:
Implement rudimentary module linking.
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.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10035028
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11374 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11331 (bd7843a0)
Original commit message:
Refactoring of code generation for declarations, in preparation for modules.
Do proper dispatch on declaration type instead of mingling together
different code generation paths. Once we add more declaration forms,
this is more scalable.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10119017
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11372 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11278 (e5dc7ebd).
Original commit message:
Skip canonicalization check in LStoreKeyedFastDoubleElement when it is not needed:
- if value is a result of integer32 to double conversion (can't be NaN);
- if value was loaded from fast double backing store (already canonicalized).
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10071004
Patch from Daniel Kalmar <kalmard@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11366 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11306 (36b58f7).
Original commit message:
This passes the isolate through to API callback functions so that it is
available through AccessorInfo and Arguments. This allows bindings to
avoid unnecessary TLS lookups to retrieve the current isolate.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10083001
Patch from Daniel Kalmar <kalmard@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11319 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11282 (bd2ab07).
Patch by Daniel Kalmar.
Original commit message:
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=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10068012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11318 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Port r11010 (1daa81bc).
MIPS-specific changes:
-register codes and registers are defined using a macro to avoid redundancy
-renamed s8_fp to fp, removed the "fp" alias
-removed kSavedValueRegister (found by check-static-initializers.sh)
Original commit message:
Landing for pliard@chromium.org: Remove static initializers in v8.
This change includes two CLs by pliard@chromium.org:
1. http://codereview.chromium.org/9447052/ (Add CallOnce() and simple LazyInstance implementation):
Note that this implementation of LazyInstance does not handle global destructors (i.e. the lazy instances a
This CL was initially reviewed on codereview.appspot.com:
http://codereview.appspot.com/5687064/
2. http://codereview.chromium.org/9455088/ (Remove static initializers in v8):
This CL depends on CL 9447052 (adding CallOnce and LazyInstance).
It is based on a patch sent by Digit.
With this patch applied, we have only one static initializer left (in atomicops_internals_x86_gcc.cc). This
This CL also modifies the presubmit script to check the number of static initializers.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9689069
Patch from Daniel Kalmar <kalmard@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11241 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
Port r11132 (91bdad6108).
Original commit message:
If all property lookups for a polymorphic load actually result in the
same field index under all maps, we can actually emit a monomorphic load
that is guarded by a map check that verifies that the actual map is in
the set of handled maps. This also allows GVN to get rid of redundant
such map checks.
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9852007
Patch from Daniel Kalmar <kalmard@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11135 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
List of changes:
-added a minor optimization to the Simulator that quickly skips nops in the delay slot
-slightly re-worked CEntryStub to save a few instructions
CEntryStub now expects the following values:
-s0: number of arguments including receiver
-s1: size of arguments excluding receiver
-s2: pointer to builtin function
Two new MacroAssembler functions were added to make usage more convenient:
-PrepareCEntryArgs(int num_args) to set up s0 and s1
-PrepareCEntryFunction(const ExternalReference&) to set up s2
-removed branch delay slot nops from the most frequently used code areas
-reorganized some code to execute fewer instructions
-utilized the delay slot of most Ret instructions
This does not cover all Rets, only the most obvious cases.
Also added a special version of DropAndRet that utilizes the delay slot.
-added some comments to code areas where explanation of the register/delay slot usage may be needed
-added an optimization to Jump so it doesn't always pre-load the target register
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9699071
Patch from Daniel Kalmar <kalmard@homejinni.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11099 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
To do this, we collect all accessor properties in a first pass and emit code for
defining those properties afterwards in a second pass.
As a finger exercise, the table used for collecting accessors has a (subset of
an) STL-like iterator interface, including STL-like names and operators.
Although C++ is quite verbose here (as usual, but partly this is caused by our
current slightly clumsy classes/templates), things work out quite nicely and it
cleans up some confusion, e.g. a table entry is not an iterator etc.
Everything compiles into very efficient code, e.g. the loop condition 'it !=
accessor_table.end()' compiles into a single 'testl' instruction on ia32.
+1 for using standard APIs!
Review URL: https://chromiumcodereview.appspot.com/9691040
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11051 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
