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
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
Yak shaving for map sharing with accessor properties contd.: When CALLBACKS can
have map transitions, simply looking at the property type is not sufficient
anymore to decide if a property is there or not. One has to look at the actual
contents of the descriptor entry then, but this breaks down sometimes when the
lookup is being done with a NULL holder. Luckily enough, we can oftren replace
IsProperty by the simpler IsFound, because we inspect the type immediately
afterwards, anyway.
Review URL: https://chromiumcodereview.appspot.com/9280007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10474 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This introduces an additional check into the StoreIC_ArrayLength builtin
checking that the array still has fast properties. Redifinitions of the
length property that would cause it's type or attributes to change, will
switch to slow properties, thereby invalidating said optimization.
R=svenpanne@chromium.org
BUG=v8:1756
TEST=test262
Review URL: http://codereview.chromium.org/8895025
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10254 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Now with arm and x64 support. Additionally, added default unreachable case to switch statement in CompareIC::TargetState to make win and mac compilers happy.
Reviewer guide:
This is an exact copy of 10216 except:
src/arm/*
src/x64/*
src/ic.cc (added default case to swith in CompareIC::TargetState)
Review URL: http://codereview.chromium.org/8872060
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10219 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This includes specialcasing the generation when we know that the maps
of the two objects are the same. In addition, a new specialized
compare ic known objects cache is created.
The reason for the cache is that we need to have access to the stub
code from the roots; if we do not, the GC will collect the stub. In
this specialized case we use the map pointer as key in the cache, and
we always do a lookup before generating code. Actually hitting
something in the cache will happen very rarely, but we could
potentially overwrite an existing stub, which again will lead to the
GC collecting this old stub (even if it is referenced from other code
objects)
Review URL: http://codereview.chromium.org/8520006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10216 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL introduces a third mode next to the non-strict
(henceforth called 'classic mode') and 'strict mode'
which is called 'extended mode' as in the current
ES.next specification drafts. The extended mode is based on
the 'strict mode' and adds new functionality to it. This
means that most of the semantics of these two modes
coincide.
The 'extended mode' is entered instead of the 'strict mode'
during parsing when using the 'strict mode' directive
"use strict" and when the the harmony-scoping flag is
active. This should be changed once it is fully specified how the 'extended mode' is entered.
This change introduces a new 3 valued enum LanguageMode
(see globals.h) corresponding to the modes which is mostly
used by the frontend code. This includes the following
components:
* (Pre)Parser
* Compiler
* SharedFunctionInfo, Scope and ScopeInfo
* runtime functions: StoreContextSlot,
ResolvePossiblyDirectEval, InitializeVarGlobal,
DeclareGlobals
The old enum StrictModeFlag is still used in the backend
when the distinction between the 'strict mode' and the 'extended mode' does not matter. This includes:
* SetProperty runtime function, Delete builtin
* StoreIC and KeyedStoreIC
* StubCache
Review URL: http://codereview.chromium.org/8417035
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10062 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Do not rely on 'default' clauses or 'if's when analysing a PropertyType, because
this makes it hard to find the relevant places when a new type is added. Note
that the detection of "phantom property types" is left untouched, because this
might have a performance impact, especially for the GC (to be investigated).
This is a preliminary step for introducing a new kind of map transition.
Review URL: http://codereview.chromium.org/8491016
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9900 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
